IEEE Transactions on Industrial Electronics

Volume 56, Number 10, Oct 2009 Access to the journal on IEEE XPLORE IE Transactions Home Page

Special Section on Advances In Motion Control-part II

56.10.1	R. Oboe, S. Bogosyan, M. Iwasaki, T. Murakami, "Guest Editor," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 3787-3789, Oct 2009. Abstract Link Full Text Abstract: Not Available Special Section Papers
56.10.2	N. Hirose, M. Iwasaki, M. Kawafuku, H. Hirai, "Deadbeat Feedforward Compensation With Frequency Shaping in Fast and Precise Position," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 3790-3797, Oct 2009. Abstract Link Full Text Abstract: This paper presents a novel deadbeat feedforward compensation technique for fast and precise positioning control in mechatronic systems. The proposed compensation provides the desired frequency shaping in control input to suppress the residual vibration, under the constraint of a specified step number in position reference. A 2-DOF positioning controller with the deadbeat feedforward compensation can ensure the required settling performance with the specified steps regardless of the positioning amplitude in reference. The effectiveness of the proposed approach has been verified by numerical simulations and experiments using a prototype of a galvano scanner.
56.10.3	B. K. Kim, W. K. Chung, K. Ohba, "Design and Performance Tuning of Sliding-Mode Controller for High-Speed and High-Accuracy Positioning Systems in Disturbance Observer Framew," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 3798-3809, Oct 2009. Abstract Link Full Text Abstract: The tuning method of controllers can be used for effectively determining the overall performance of positioning systems. In particular, this method is highly effective in the case of high-speed and high-accuracy positioning systems. In this paper, a sliding-mode controller that uses one of the well-known approaches of robust control methodology is designed for high-speed positioning systems that require a high-accuracy performance. A performance-tuning method based on a disturbance observer (DOB) structure is also proposed. First, a generalized disturbance attenuation framework named robust internal-loop compensator (RIC) is introduced, and a sliding-mode controller based on a Lyapunov redesign is analyzed in the RIC framework. Then, the DOB properties of the sliding-mode controller are presented, and it is shown that the performance of the closed-loop system with a sliding-mode controller can be tuned up by using the structural characteristics of the DOB. These results make the design of an enhanced sliding-mode controller possible. Finally, the proposed algorithm is experimentally verified and discussed with two positioning systems. Experimental results show the effectiveness and the robustness of the proposed scheme.
56.10.4	K. Jezernik, M. Rodic, "High Precision Motion Control of Servo Dri," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 3810-3816, Oct 2009. Abstract Link Full Text Abstract: In this paper, we investigate the advantages and feasibility of motor control using very fast (in megahertz) switching in place of traditional amplifiers. We also propose integrated motion-control architecture based on discrete-event control approach to be implemented in digital logic at an equally high rate. A switching controller combines the current and motion feedback paths into a single loop. A model-based observer estimates the load torque. When compared to second-order controllers implemented with traditional amplifiers, the proposed design promises increased performance, better efficiency, and improved load estimation. Simple implementation makes concepts of switching control very attractive in motion-control systems like control of dc or ac servomotors. The control algorithm designed by the proposed approach can be easily implemented on field programmable gate array platforms.
56.10.5	M. Hirata, T. Kidokoro, "Servo Performance Enhancement of Motion System via a Quantization Error Estimation Method—Introduction to Nanoscale Servo Cont," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 3817-3824, Oct 2009. Abstract Link Full Text Abstract: When compared to the accuracy of nanoscale control, the resolution of current positioning sensors is relatively low. Because of this, the output from low-precision sensors normally includes quantization errors that could degrade control performance. As a result, in this paper, a method of quantization error estimation based on the least square method is examined. In the proposed method, estimation accuracy is improved by taking into account the effect of input disturbances. Furthermore, a bias adjustment method is proposed that is expected to satisfy the constraints on quantization error. The effectiveness of the proposed method is demonstrated by simulations and experiments.
56.10.6	H. Fujimoto, "RRO Compensation of Hard Disk Drives With Multirate Repetitive Perfect Tracking Cont," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 3825-3831, Oct 2009. Abstract Link Full Text Abstract: In this paper, novel repetitive controllers are proposed based on perfect tracking control (PTC) in order to reject high-order repeatable runout (RRO) of hard disk drives. First, the feedback approach of the repetitive PTC (RPTC) is developed with internal model of periodic disturbance. Although this method has performance robustness against small plant variation, the internal model worsens the stability robustness for big modeling error. Then, the feedforward (FF) approach of RPTC is introduced with switching mechanism such that the high-order RRO can be rejected without any sacrifice of the closed-loop characteristics. In both approaches, multirate FF control is utilized to overcome the unstable zero problem of discrete-time plant. Finally, the advantages and disadvantages are demonstrated through simulations and experiments.
56.10.7	L. Mostefai, M. Denai, O. Sehoon, Y. Hori, "Optimal Control Design for Robust Fuzzy Friction Compensation in a Robot Jo," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 3832-3839, Oct 2009. Abstract Link Full Text Abstract: This paper presents a methodology for the compensation of nonlinear friction in a robot joint structure based on a fuzzy local modeling technique. To enhance the tracking performance of the robot joint, a dynamic model is derived from the local physical properties of friction. The model is the basis of a precompensator taking into account the dynamics of the overall corrected system by means of a minor loop. The proposed structure does not claim to faithfully reproduce complex phenomena driven by friction. However, the linearity of the local models simplifies the design and implementation of the observer, and its estimation capabilities are improved by the nonlinear integral gain. The controller can then be robustly synthesized using linear matrix inequalities to cancel the effects of inexact friction compensation. Experimental tests conducted on a robot joint with a high level of friction demonstrate the effectiveness of the proposed fuzzy observer-based control strategy for tracking system trajectories when operating in zero-velocity regions and during motion reversals.
56.10.8	M. Ruderman, F. Hoffmann, T. Bertram, "Modeling and Identification of Elastic Robot Joints With Hysteresis and Backl," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 3840-3847, Oct 2009. Abstract Link Full Text Abstract: This paper presents a novel approach to the modeling and identification of elastic robot joints with hysteresis and backlash. The model captures the dynamic behavior of a rigid robotic manipulator with elastic joints. The model includes electromechanical submodels of the motor and gear from which the relationship between the applied torque and the joint torsion is identified. The friction behavior in both presliding and sliding regimes is captured by Generalized Maxwell-Slip model. The hysteresis is described by a Preisach operator. The distributed model parameters are identified from experimental data obtained from internal system signals and external angular encoder mounted to the second joint of a 6-DOF industrial robot. The validity of the identified model is confirmed by the agreement of its prediction with independent experimental data not previously used for model identification. The obtained models open an avenue for future advanced high-precision control of robotic manipulator dynamics.
56.10.9	Z. Jamaludin, H. Van Brussel, J. Swevers, "Friction Compensation of an $XY$ Feed Table Using Friction-Model-Based Feedforward and an Inverse-Model-Based Disturbance Obser," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 3848-3853, Oct 2009. Abstract Link Full Text Abstract: Uncompensated friction forces compromise the positioning and tracking accuracy of motion systems. A unique tracking error known as quadrant glitch is the result of complex nonlinear friction behavior at motion reversal or near-zero velocity. Linear-feedback control strategies such as PID, cascade P/PI, or state-feedback control have to be extended with model- and nonmodel-based friction-compensation strategies to acquire sufficiently high path and tracking accuracy. This paper analyzes and validates experimentally three different friction-compensation strategies for a linear motor-based $xy$ feed drive of a high-speed milling machine: 1) friction-model-based feedforward; 2) an inverse-model-based disturbance observer; and 3) the combination of both techniques. The friction models considered are as follows: a simple static-friction model and the recently developed generalized Maxwell-slip (GMS) model. GMS friction-model-based feedforward combined with disturbance observer almost completely eliminates the radial tracking error and quadrant glitches.
56.10.10	S. Katayama, K. Yubai, J. Hirai, "Iterative Design of the Reduced-Order Weight and Controller for the $H_{infty}$ Loop-Shaping Method Under Open-Loop Magnitude Constraints for SISO Syst," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 3854-3863, Oct 2009. Abstract Link Full Text Abstract: The $H_{infty}$ loop-shaping method is known to be an effective control method. However, it has two drawbacks. The first is that it is difficult to select appropriate loop-shaping weights, and the second is that the resulting controller is very complex. For the first drawback, Lanzon has proposed a suboptimal loop-shaping weight design method. It is formulated as a generalized eigenvalue minimization problem (GEVP). This suboptimal loop-shaping weight design method provides high-order weights, exacerbating the second drawback. To resolve these two drawbacks, a reduced-order loop-shaping weight design method is proposed for SISO systems in this paper. In the proposed method, the weight structure is first fixed, and the weight is then decomposed into a frequency-dependent vector and parameter matrices characterizing the loop-shaping weight. Since the open-loop constraints are represented as linear matrix inequalities with respect to the parameter matrices, the proposed reduced-order loop-shaping weight design problem for SISO systems is formulated as a GEVP, as well as Lanzon's suboptimal loop-shaping weight design method. The proposed method can reduce the designer's burden, although it is only valid for SISO systems. The effectiveness of the proposed method is verified experimentally by velocity control of a belt-driven two-mass system.
56.10.11	K. Seki, M. Iwasaki, M. Kawafuku, H. Hirai, K. Yasuda, "Adaptive Compensation for Reaction Force With Frequency Variation in Shaking Table Syst," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 3864-3871, Oct 2009. Abstract Link Full Text Abstract: This paper presents an adaptive control methodology of a shaking table system for earthquake simulators. In the system, reaction forces generated by a specimen deteriorate the table motion performance, resulting in lower control accuracy in seismic tests. In particular, in cases of excitation tests for structures (power facilities, large vehicles, etc.) including motors with periodic rotation, the reaction force as a disturbance is excited with a specific frequency during their actual operations. In addition, the variation of the rotational frequency in the motor causes the variation of frequency in the disturbance. In order to compensate for the disturbance, therefore, an adaptive feedback compensator is designed to improve the disturbance suppression capability, by applying an adaptive notch filter to identify the frequency in an online manner. The proposed control approach has been verified by experiments using a prototype of a shaking table system.
56.10.12	S. Cong, Y. Liang, "PID-Like Neural Network Nonlinear Adaptive Control for Uncertain Multivariable Motion Control Syst," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 3872-3879, Oct 2009. Abstract Link Full Text Abstract: A mix locally recurrent neural network was used to create a proportional-integral-derivative (PID)-like neural network nonlinear adaptive controller for uncertain multivariable single-input/multi-output system. It is composed of a neural network with no more than three neural nodes in hidden layer, and there are included an activation feedback and an output feedback, respectively, in a hidden layer. Such a special structure makes the exterior feature of the neural network controller able to become a P, PI, PD, or PID controller as needed. The closed-loop error between directly measured output and expected value of the system is chosen to be the input of the controller. Only a group of initial weights values, which can run the controlled closed-loop system stably, are required to be determined. The proposed controller can update weights of the neural network online according to errors caused by uncertain factors of system such as modeling error and external disturbance, based on stable learning rate. The resilient back-propagation algorithm with sign instead of the gradient is used to update the network weights. The basic ideas, techniques, and system stability proof were presented in detail. Finally, actual experiments both of single and double inverted pendulums were implemented, and the comparison of effectiveness between the proposed controller and the linear optimal regulator were given.
56.10.13	R. Antonello, R. Oboe, L. Prandi, F. Biganzoli, "Automatic Mode Matching in MEMS Vibrating Gyroscopes Using Extremum-Seeking Cont," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 3880-3891, Oct 2009. Abstract Link Full Text Abstract: In order to enhance the sensitivity and to reduce the readout circuit complexity of any angular velocity microsensor (vibrating gyroscope), it is crucial to reduce the frequency mismatch of its resonant modes of vibration. Achieving a good matching accuracy during fabrication is rather difficult because of tolerances and process variations that detrimentally affect the manufacturing precision. Moreover, even assuming to achieve a good frequency matching through fabrication or postfabrication calibration, it is very likely that parametric variations induced by the external environment during the normal operation of the device disrupt any initial tuning. For these reasons, in this paper, an alternative way to accomplish the frequency-matching condition is suggested, which exploits a real-time adjusting mechanism based on an automatic mode-matching control loop. In particular, this paper describes the details of an adaptive controller capable of automatically matching the resonant frequencies of the two main modes of vibration of a single-axis vibrating microgyroscope, under the provision that there is an underlying mechanism through which the frequency mismatch can be controlled by adjusting a suitable tunable parameter. The controller is designed by considering the requirement of reducing its complexity, so that it can be easily implemented on cheap sensors. Owing to a key observation that allows the recast of the frequency-matching problem as a maximization problem, the proposed mode-matching controller is actually designed as a standard perturbation-based extremum-seeking controller, which can be implemented by using few analog electronic components. The proposed solution has been tested on the LISY300AL yaw-rate microelectromechanical system gyroscope manufactured by STMicroelectronics, showing that a mode matching of nearly 1 Hz or less can be easily attained.
56.10.14	N. Uchiyama, T. Hashimoto, S. Sano, S. Takagi, "Model-Reference Control Approach to Obstacle Avoidance for a Human-Operated Mobile Ro," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 3892-3896, Oct 2009. Abstract Link Full Text Abstract: Because the obstacle-avoidance function is indispensable for providing the safe and easy operation of human-operated robotic systems, this paper deals with the obstacle-avoidance control for a human-operated mobile robot in unknown environments. A general type of two-wheeled mobile robot with inexpensive distance sensors to detect obstacles is considered. Because the robot cannot move in arbitrary directions due to a nonholonomic constraint, we propose a model-reference control approach, in which a reference model generates the desired trajectory to satisfy the nonholonomic constraint, and the robot follows the desired trajectory. The reference model has the steering-like and brake-like functions that are adjusted according to the distance-sensor information. The stability of the proposed control system is analyzed with a linear model. The effectiveness of the proposed method is confirmed by experiments in which several operators handle the robot in an environment with obstacles.
56.10.15	C. Mitsantisuk, S. Katsura, K. Ohishi, "Kalman-Filter-Based Sensor Integration of Variable Power Assist Control Based on Human Stiffness Estimat," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 3897-3905, Oct 2009. Abstract Link Full Text Abstract: In applications such as robot collaborating with human operators, the robot system must operate more slowly and be more compliant to safe user interaction. Moreover, a consideration of the dynamic properties of human operators is also important for the human application. According to such requirements, this paper presents a novel sensorless force control approach for the robot-assisted motion of the human arm. A twin direct-drive motor system with a wire rope has been developed to provide a precise force sensation and safety for human–robot interaction. In order to control the wire rope tension and human interaction force, two mode designs of the force control are realized. The common mode is utilized for the control of wire rope tension. In the differential mode, the Kalman-filter-based sensor integration for the interaction force observer is proposed in this paper. By combining two motor encoders and a commercial acceleration sensor together, white Gaussian noise is reduced, and high accurate feedback of the contact force is obtained. A variable power assist control method based on a real-time estimation of the stiffness of the human arm is also introduced. By considering the stiffness in human arm movements, this method increases the efficiency of the force control system and realizes comfortable force for human–robot interaction. The effectiveness of the method is verified by experimental results.
56.10.16	Y. Yokokura, S. Katsura, K. Ohishi, "Stability Analysis and Experimental Validation of a Motion-Copying Sys," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 3906-3913, Oct 2009. Abstract Link Full Text Abstract: This paper examines the stability of our proposed motion-copying system in the case that the environmental mechanical impedance is changed. The system preserves and reproduces the motion of the human operator. The examination of this paper derives the transfer function of the motion-loading system considering the environmental impedance and investigates displacement of the poles with the transition of the environment. Moreover, the experiment with respect to environmental changing is carried out. These results confirm theoretically and experimentally that the motion-copying system is stable even if the environment is changed. The haptic informational processing technique by the motion-copying system is useful for industrial applications and medical engineering.
56.10.17	S. Komada, Y. Hashimoto, N. Okuyama, T. Hisada, J. Hirai, "Development of a Biofeedback Therapeutic-Exercise-Supporting Manipula," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 3914-3920, Oct 2009. Abstract Link Full Text Abstract: Although much equipment for physical therapy has been developed, equipment to improve the quality of physical therapy is scarce. We propose a robotic biofeedback exercise device that can display human joint torque and muscle force during training without a problematic electromyogram (EMG). The purpose is to increase the therapeutic value by understanding a person's condition during exercise and to provide an incentive to improve performance. The manipulator supports lower limb rehabilitation in the sagittal plane. With its ability to adjust the maximum speed and the time constant, the manipulator provides simultaneous and safe isokinetic exercise for the knee and hip joints. This paper describes the estimation of the human joint torque and muscle force. The display of the joint torque and the muscle force is realized during exercise of the knee joint using the developed manipulator. The estimation of the muscle force from Crowninshield's method and Hase's method generally agrees with the EMG.
56.10.18	O. Gerelli, C. G. Lo Bianco, "Nonlinear Variable Structure Filter for the Online Trajectory Scal," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 3921-3930, Oct 2009. Abstract Link Full Text Abstract: Time efficiency and accurate path tracking represent two conflicting demands typical of robotic applications: Time efficiency induces one to plan extremely fast trajectories which can easily collide with the manipulator kinematic and dynamic constraints, thus causing a reduction of accuracy. To deal with this problem, several approaches can be found in the literature mainly based on the synthesis of dynamic filters used for the online trajectory scaling: A possibly unfeasible input trajectory is automatically scaled to fulfill given dynamic bounds. In this way, an accurate path tracking is guaranteed. This paper can be collocated in such a framework. A new discrete-time filter, with novel capabilities, is designed. Differently from other proposals, not only torque constraints are considered but also kinematic constraints are easily handled. Moreover, to preserve time efficiency, the new filter always attempts to recover any delay caused by the constraints.
56.10.19	C.-F. Juang, C.-H. Hsu, "Reinforcement Ant Optimized Fuzzy Controller for Mobile-Robot Wall-Following Cont," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 3931-3940, Oct 2009. Abstract Link Full Text Abstract: This paper proposes a reinforcement ant optimized fuzzy controller (FC) design method, called RAOFC, and applies it to wheeled-mobile-robot wall-following control under reinforcement learning environments. The inputs to the designed FC are range-finding sonar sensors, and the controller output is a robot steering angle. The antecedent part in each fuzzy rule uses interval type-2 fuzzy sets in order to increase FC robustness. No a priori assignment of fuzzy rules is necessary in RAOFC. An online aligned interval type-2 fuzzy clustering (AIT2FC) method is proposed to generate rules automatically. The AIT2FC not only flexibly partitions the input space but also reduces the number of fuzzy sets in each input dimension, which improves controller interpretability. The consequent part of each fuzzy rule is designed using $Q$-value aided ant colony optimization (QACO). The QACO approach selects the consequent part from a set of candidate actions according to ant pheromone trails and $Q$-values, both of whose values are updated using reinforcement signals. Simulations and experiments on mobile-robot wall-following control show the effectiveness and efficiency of the proposed RAOFC.
56.10.20	W. Chung, S. Kim, M. Choi, J. Choi, H. Kim, C. Moon, J.-B. Song, "Safe Navigation of a Mobile Robot Considering Visibility of Environm," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 3941-3950, Oct 2009. Abstract Link Full Text Abstract: We present one approach to achieve safe navigation in an indoor dynamic environment. So far, there have been various useful collision avoidance algorithms and path planning schemes. However, those algorithms possess fundamental limitations in that the robot can avoid only “visible” ones among surrounded obstacles. In a real environment, it is not possible to detect all the dynamic obstacles around the robot. There are many occluded regions due to the limited field of view. In order to avoid collisions, it is desirable to exploit visibility information. This paper proposes a safe navigation scheme to reduce collision risk considering occluded dynamic obstacles. The robot's motion is controlled by the hybrid control scheme. The possibility of collision is dually reflected to path planning and speed control. The proposed scheme clearly indicates the structural procedure on how to model and to exploit the risk of navigation. The proposed scheme is experimentally tested in a real office building. The experimental results show that the robot moves along the safe path to obtain sufficient field of view. In addition, safe speed constraints are applied in motion control. It is experimentally verified that a robot safely navigates in dynamic indoor environment by adopting the proposed scheme.
56.10.21	J. Ghommam, F. Mnif, "Coordinated Path-Following Control for a Group of Underactuated Surface Vess," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 3951-3963, Oct 2009. Abstract Link Full Text Abstract: This paper addresses the problem of coordinating a group of underactuated ships along given paths (path following) while holding a desired intership formation pattern. The solution to this problem unfolds into two basic subproblems. In the first step, a path-following controller is derived to force each underactuated ship to follow a reference path subject to constant disturbances induced by wave, wind, and ocean current. The controller is designed such that the ship moves on the path while its total velocity is maintained tangential to the path. In the second step, the speeds of the vehicles are adjusted so as to synchronize the positions of the corresponding virtual targets (or so-called coordination states), in the sense that the derivative of each path is left as a free input to synchronize the ships' motion. The proposed coordination controller uses a combination of Lyapunov direct method, backstepping, and concepts from graph theory. When dealing with the path-following coordination problem, it is considered that each ship transmits its coordination state to other ships with a varying time delay as determined by the communication topology. The coordination errors' convergence is achieved based on a proposed Lyapunov–Krasovskii function. Simulation results are provided to illustrate the effectiveness of the proposed approach.
56.10.22	E. Ohashi, T. Sato, K. Ohnishi, "A Walking Stabilization Method Based on Environmental Modes on Each Foot for Biped Ro," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 3964-3974, Oct 2009. Abstract Link Full Text Abstract: In this paper, a method that makes biped robots track zero-moment-point (ZMP) reference trajectories is proposed. The biped robots have flat rectangular soles with force sensors at each corner. The sensors detect reaction force from the ground. Sensor information is transformed into useful structure, which is defined as “environmental modes.” The environmental modes represent contact states between the ground and the soles and are extracted by the information of four force sensors at each corner of the rectangular soles. The environmental modes consist of the following four modes: 1) heaving; 2) rolling; 3) pitching; and 4) twisting. These modes are related to the ZMP, by which walking stability is evaluated. Therefore, command values of the environmental modes can be derived by the ZMP reference trajectory. By tracking the command values, the walking motion becomes more stable. The conventional study on controlling the environmental modes takes only the rolling and pitching modes into account. However, it is not sufficient to stabilize the walking motion, because the heaving mode has been neglected. The heaving mode is also very important to stabilize the walking motion. Therefore, in this paper, we extend the conventional method for considering the heaving mode to track the ZMP reference trajectory. Validity of the proposed method was confirmed by experimental results.
56.10.23	W. Chung, C. Rhee, Y. Shim, H. Lee, S. Park, "Door-Opening Control of a Service Robot Using the Multifingered Robot H," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 3975-3984, Oct 2009. Abstract Link Full Text Abstract: Service robots are spreading their application areas to human coexisting real environments. However, it is still difficult to find an autonomous robot that is capable of manipulation services in a real environment. The three major difficulties of manipulation service can be summarized as follows: 1) unstructured human-centered environment; 2) limited resources in a robot; and 3) uncertainties in real environments. This paper deals with the autonomous manipulation task by a service robot in human coexisting environment. We focus on a door-opening problem. In this paper, we concentrate on three issues from the viewpoint of service-robot applications. The first issue is to estimate kinematic parameters by using an active-sensing strategy to overcome uncertainties in a real environment. The second issue is to provide an integrated strategy of motion coordination for door-opening control. This paper discusses the role assignment of each subsystem that depends on the physical characteristics. The third issue is to use the fingertip-contact forces to estimate the external force from a doorknob, instead of using an additional high-cost force sensor at the wrist. The proposed scheme is shown to be useful through experimental results.
56.10.24	T. Takei, R. Imamura, S. Yuta, "Baggage Transportation and Navigation by a Wheeled Inverted Pendulum Mobile Ro," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 3985-3994, Oct 2009. Abstract Link Full Text Abstract: Our goal is to configure an automatic baggage-transportation system by an inverted pendulum robot and realize a navigation function in a real environment. The system consists of two cooperative subsystems: a balancing-and-traveling control subsystem and a navigation subsystem. Position errors of the inverted pendulum robot are often caused by a drift error in the gyro sensor and a change in the center of gravity by a loaded baggage when applying the linear state feedback control method for balancing and traveling. We have reduced the position errors for navigation by resetting the balance position occasionally while traveling with simple methods without an external observer or alternative sensors. In this paper, we state the method and show the experimental results of navigation in a real environment by the implemented robot system. Special Section on The 2008 IEEE International Symposium on Industrial Electronics
56.10.25	G. Asher, C. Cecati, M. N. Cirstea, E. Monmasson, "Guest Editor," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 3995-3997, Oct 2009. Abstract Link Full Text Abstract: Not Available Special Section Papers
56.10.26	S.-K. Lam, T. Srikanthan, C. T. Clarke, "Selecting Profitable Custom Instructions for Area–Time-Efficient Realization on Reconfigurable Architectu," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 3998-4005, Oct 2009. Abstract Link Full Text Abstract: Profitable custom instructions provide higher performance for a given reconfigurable area. Hence, choosing profitable custom instructions that are also area–time efficient is essential if design constraints must be met by field-programmable-gate-array (FPGA)-based reconfigurable processors. In this paper, we propose a framework for FPGA-based reconfigurable processors in order to rapidly identify a reduced set of profitable custom instructions without the need for actual hardware synthesis. The proposed framework is capable of estimating the area utilization and latencies of custom instructions on lookup-table-based commercial FPGAs. Simulations based on 15 applications from benchmark suites show that the proposed method provides, on average, an area reduction of over 29% for loss of mere 1.3% in compute performance. Our evaluations also confirm that the proposed framework is superior to an existing area-optimization approach that relies on exploiting the regularity of custom instruction data paths. In particular, an average area–time product gain of over 59% was achieved by deploying a reduced set of custom instructions obtained using the proposed framework.
56.10.27	L. Idkhajine, E. Monmasson, M. W. Naouar, A. Prata, K. Bouallaga, "Fully Integrated FPGA-Based Controller for Synchronous Motor Dr," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 4006-4017, Oct 2009. Abstract Link Full Text Abstract: The aim of this paper is to present a fully integrated solution for synchronous motor control. The implemented controller is based on Actel Fusion field-programmable gate array (FPGA). The objective of this paper is to evaluate the ability of the proposed fully integrated solution to ensure all the required performances in such applications, particularly in terms of control quality and time/area performances. To this purpose, a current control algorithm of a permanent-magnet synchronous machine has been implemented. This machine is associated with a resolver position sensor. In addition to the current control closed loop, all the necessary motor control tasks are implemented in the same device. The analog-to-digital conversion is ensured by the integrated analog-to-digital converter (ADC), avoiding the use of external converters. The resolver processing unit, which computes the rotor position and speed from the resolver signals, is implemented in the FPGA matrix, avoiding the use of external resolver-to-digital converter (RDC). The sine patterns used for the Park transformation are stored in the integrated Flash memory blocks.
56.10.28	I. Chowdhury, D. Ma, "Design of Reconfigurable and Robust Integrated SC Power Converter for Self-Powered Energy-Efficient Devi," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 4018-4028, Oct 2009. Abstract Link Full Text Abstract: Motivated by emerging self-sustained low-power applications, an integrated power supply solution with a reconfigurable step-up/down switched-capacitor power stage and a dual-loop adaptive gain-pulse control is presented. It makes use of a reconfigurable power stage structure to implement variable gain ratios that provide efficient voltage conversion within wide input/output voltage and power ranges. It also employs an interleaving regulation scheme to significantly reduce the input inrush currents and the output voltage ripples with fast transient response. Design strategy, system optimization, and circuit implementation are addressed in detail. The converter was designed with a standard 0.35-$muhbox{m}$ digital CMOS n-well process. With an input voltage ranging from 1.5 to 3.3 V, the converter achieves variable step-up/down voltage conversion with a maximum load current of 90 mA. The maximum efficiency is 88%. The converter responds to a 70-mA load-current step change within 4.6 $muhbox{s}$, while it robustly operates under a 1.8-V input supply variation. The design can be easily extended and reconfigured for different operation and application scenarios.
56.10.29	A. Timbus, M. Larsson, C. Yuen, "Active Management of Distributed Energy Resources Using Standardized Communications and Modern Information Technolog," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 4029-4037, Oct 2009. Abstract Link Full Text Abstract: Due to high penetration level in some regions of distributed generators (DGs) based on renewable energy resources, information about their power delivery capabilities is becoming essential for planning and allocating resources and reserves in power system. This paper discusses the modeling of DGs in the utility control and information technology infrastructures of power system operators. The communication standards International Electrotechnical Commission (IEC) 61400-25 and IEC 61850 and their extensions for DGs are first introduced, followed by an example of mapping wind turbine components onto a communication data model. A distribution network comprising several distributed-generation sources is then described from the control and communication point of view. Simulation results of production cost minimization and network constraint management are presented at the end, illustrating the new possibilities that a system-wide approach can provide for distributed generation.
56.10.30	K. Szabat, T. Orlowska-Kowalska, M. Dybkowski, "Indirect Adaptive Control of Induction Motor Drive System With an Elastic Coupl," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 4038-4042, Oct 2009. Abstract Link Full Text Abstract: In this paper, an adaptive control strategy for the field oriented controlled induction motor (IM) drive system with elastic joint is presented. The changeable inertia of the load machine is estimated by the nonlinear extended Kalman filter. Then, the control structure parameters are retuned in accordance with the estimated value. The provided experimental results for the IM drive confirm the effectiveness of the proposed strategy. Special Section Papers
56.10.31	T. Orlowska-Kowalska, M. Kaminski, "Effectiveness of Saliency-Based Methods in Optimization of Neural State Estimators of the Drive System With Elastic Coupli," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 4043-4051, Oct 2009. Abstract Link Full Text Abstract: This paper deals with the optimization problem of internal structure of neural-network (NN)-based state estimators of the drive system with elastic joints. Saliency-based optimization methods, developed in the NN theory, are tested in this paper to obtain the high-quality estimation of torsional torque and load-machine speed. The optimal brain damage and optimal brain surgeon methods are compared in this application. The state variables estimated by the optimized NN are used in feedback paths in the two-mass drive structure with a state controller. The simulation results show good accuracy of both presented neural estimators for a wide range of changes of the reference speed and the load torque. The simulation results are verified by laboratory experiments.
56.10.32	M. Nemec, K. Drobnic, D. Nedeljkovic, V. Ambrozic, "Direct Current Control of a Synchronous Machine in Field Coordina," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 4052-4061, Oct 2009. Abstract Link Full Text Abstract: This paper presents an implementation of a modified method for direct current control (DCC) in a permanent-magnet synchronous motor (SM). The control is performed using a predictive algorithm in rotor field coordinates due to its simpler implementation. Its task is to minimize the final current error at the end of the sampling interval. Depending on the desired performance, two variants are proposed, yielding either lower switching frequency or lower current ripple. Both variants of DCC, named DCC I and DCC II, have been rearranged for applications in SMs with either surface-mounted permanent magnets or interior (buried) permanent magnets. A comparison with field-oriented control using space-vector modulation and synchronized on/off modulation shows the advantages and drawbacks of the proposed method. Simulations and measurements on a laboratory model with SM having low inductances (thus expecting high ripple) and very high number of poles (high stator supply frequency) confirm the validity of the approach. Additional considerations regarding practical problems, some of which can be found in similar predictive methods, are also presented.
56.10.33	O. Poncelas, J. A. Rosero, J. Cusido, J. A. Ortega, L. Romeral, "Motor Fault Detection Using a Rogowski Sensor Without an Integra," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 4062-4070, Oct 2009. Abstract Link Full Text Abstract: This paper presents a new approach for the current acquisition system in motor fault detection applications. This paper includes the study, design, and implementation of a Rogowski-coil current sensor without the integrator circuit that is typically used. The circuit includes an autotuning block able to adjust to different motor speeds. Equalizing the amplitudes of the fundamental and fault harmonics leads to higher precision current measurements. The resulting compact sensor is used as a current probe for fault detection in induction motors through motor current signal analysis. The use of a Rogowski coil without an integrator allows a better discrimination of the fault harmonics around the third and fifth main harmonics. Finally, the adaptive conditioning circuit is tested over an induction machine drive. Results are presented, and quantitative comparisons are carried out.
56.10.34	A. Facchinetti, M. Mauri, "Hardware-in-the-Loop Overhead Line Emulator for Active Pantograph Test," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 4071-4078, Oct 2009. Abstract Link Full Text Abstract: Pantograph active control is considered as a means to improve the current collection quality in high-speed railways. Different studies have focused on the assessment of pantograph control systems, addressing actuator configurations and control strategies, mainly by means of numerical experiments. In the last few years, it has become possible to transfer the knowledge gained from numerical experiments to real operating conditions. Due to the high cost of on-track tests, which are necessary for the final assessment of active pantograph performances, it is desirable to perform these tests on a system that has already demonstrated its capabilities with less expensive laboratory tests, in which at least the basic features of the real operating conditions are reproduced. This paper deals with the development of a hardware-in-the-loop (HIL) test rig, which allows the reproduction of the dynamical interaction between the overhead lines and the pantograph in high-speed railways. The HIL test rig makes it possible to verify the control strategies, the electrical drive configurations for active control, and the contact force estimation procedures on a real pantograph under conditions that are similar to those encountered on the real line. Some examples of test bench applications for pantograph active control and contact force estimation are also presented.
56.10.35	G. Fedele, C. Picardi, D. Sgro, "A Power Electrical Signal Tracking Strategy Based on the Modulating Functions Met," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 4079-4087, Oct 2009. Abstract Link Full Text Abstract: The number of pieces of equipment based on static converters such as uninterrupted power systems, series or shunt compensators, and distributed generation systems is increasing in the actual power distribution systems. For correct operation in grid-connected condition, these equipment need the information about amplitude, phase angle, and frequency of the grid fundamental voltages and currents. Since noise, harmonic pollution, and frequency variations are common problems in the utility grid, then it is necessary to have systems able to extract information about the fundamental values from highly distorted signals. For these reasons, robust and accurate estimation and synchronization methods are necessary to obtain the aforementioned information also in noise environmental. This paper presents a power electrical signal tracking strategy consisting in the combined use of a simple and robust frequency estimation method based on modulating functions and an orthogonal system generator including the second-order generalized integrator. The proposed strategy has the advantages of a fast and accurate signal tracking capability and a good rejection to noise due to the low-pass filter properties of the modulating functions. The effectiveness of the proposed method is validated through comparisons with existing methods performing simulated and laboratory experiments.
56.10.36	J. C. Vasquez, J. M. Guerrero, A. Luna, P. Rodriguez, R. Teodorescu, "Adaptive Droop Control Applied to Voltage-Source Inverters Operating in Grid-Connected and Islanded Mo," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 4088-4096, Oct 2009. Abstract Link Full Text Abstract: This paper proposes a novel control for voltage-source inverters with the capability to flexibly operate in grid-connected and islanded modes. The control scheme is based on the droop method, which uses some estimated grid parameters such as the voltage and frequency and the magnitude and angle of the grid impedance. Hence, the inverter is able to inject independently active and reactive power to the grid. The controller provides a proper dynamics decoupled from the grid-impedance magnitude and phase. The system is also able to control active and reactive power flows independently for a large range of impedance grid values. Simulation and experimental results are provided in order to show the feasibility of the control proposed.
56.10.37	D. Yazdani, A. Bakhshai, G. Joos, M. Mojiri, "A Real-Time Three-Phase Selective-Harmonic-Extraction Approach for Grid-Connected Convert," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 4097-4106, Oct 2009. Abstract Link Full Text Abstract: This paper introduces a new three-phase harmonic-decomposition technique to extract voltage/current harmonics for use in grid-connected converters, such as for active power filters (APFs). The main function of this technique is to detect a selective order of harmonics for control purposes. This feature is useful when elimination of certain harmonics is of concern. Moreover, the proposed method can successfully detect and track the variations in the frequency of the signal and extract the time-varying harmonics. A theoretical analysis is presented, and the performance of the method is experimentally evaluated. The methodology is applicable for a wide range of equipment such as uninterruptible power supplies, regenerative converters, APFs, etc., as a basis for the detection of the reference signals.
56.10.38	D. Dujic, M. Jones, S. N. Vukosavic, E. Levi, "A General PWM Method for a $(2n + 1)$ -Leg Inverter Supplying $n$ Three-Phase Machi," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 4107-4118, Oct 2009. Abstract Link Full Text Abstract: Control of an ac machine requires only two currents. It is, therefore, possible to achieve independent control of a number of three-phase machines using various inverter topologies with a reduced switch count. One such drive system comprises $n$ three-phase induction machines supplied by a $(2n + 1)$-leg voltage source inverter (VSI). In such a configuration, one inverter leg is common for all machines. This paper presents a general pulsewidth modulation (PWM) method that is applicable for any number of machines $n$ in the group. It is based on utilization of the standard three-phase modulators in conjunction with additional logic to generate modulation signals for all $(2n + 1)$ legs of the inverter, and it enables an arbitrary distribution of the available dc bus voltage between the $n$ machines. A developed PWM method has been implemented and tested in two-machine, three-machine, and four-machine drives, supplied from five-leg, seven-leg, and nine-leg VSIs, respectively. Experimental results are reported for open-loop $V/f$ control, closed-loop current-controlled $V/f$ mode of operation, and full vector control. It is shown that the nonideal nature of the VSI causes unsatisfactory operation of the drive system in the open-loop $V/f$ mode, and that closed-loop current control is, therefore, preferred in this type of a drive system. It is believed that the four-machine drive has a good potential for industrial applications since, in certai- n cases, it enables a considerable saving in the required number of switches and installed inverter power.
56.10.39	A. Lega, M. Mengoni, G. Serra, A. Tani, L. Zarri, "Space Vector Modulation for Multiphase Inverters Based on a Space Partitioning Algori," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 4119-4131, Oct 2009. Abstract Link Full Text Abstract: Since the late 1990s, multiphase drives have become a serious alternative to three-phase drives in some particular applications such as electric ship propulsion, locomotive traction, electric vehicles, and high-power industrial applications. Nowadays, the research activity is focused on the development of control strategies that can exploit the degrees of freedom that exist in multiphase machines. As known, a multiphase motor cannot be analyzed using the space vector representation in a single $d$ –$q$ plane, but it is necessary to introduce multiple $d$–$q$ planes. In this paper, the problem of the space vector modulation (SVM) of multiphase inverters is solved extending the theory of SVM used for traditional three-phase voltage source inverters and introducing the concept of reciprocal vector. The proposed approach, confirmed by experimental tests, allows the full exploitation of the dc input voltage and the simultaneous modulation of voltage space vectors in different $d$–$q$ planes.
56.10.40	I. Villar, U. Viscarret, I. Etxeberria-Otadui, A. Rufer, "Global Loss Evaluation Methods for Nonsinusoidally Fed Medium-Frequency Power Transform," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 4132-4140, Oct 2009. Abstract Link Full Text Abstract: Medium-voltage conversion systems, such as traction and grid-connected converters, are continuously evolving toward higher power densities. Consequently, volume, weight, and material reductions are becoming major design issues, which lead the research focus toward high-/medium-frequency isolated power conversion systems. An optimized design of these conversion systems requires a detailed transformer-loss evaluation considering both copper and core losses. This paper presents a simple and flexible methodology to analyze global medium-frequency transformer losses in an isolated dc–dc converter fed by general nonsinusoidal waveforms. Various loss evaluation approaches are considered, pointing out their validity and limitations by means of finite-element simulations and experimental tests.
56.10.41	G. Asher, C. Chakraborty, "Guest Editor," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 4141-4142, Oct 2009. Abstract Link Full Text Abstract: Not Available
56.10.42	L. Xu, D. Zhi, B. W. Williams, "Predictive Current Control of Doubly Fed Induction Generat," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 4143-4153, Oct 2009. Abstract Link Full Text Abstract: This paper presents a predictive current control (PCC) strategy for doubly fed induction generators (DFIGs). The method predicts the DFIG's rotor current variations in the synchronous reference frame fixed to the stator flux within a fixed sampling period. This is then used to directly calculate the required rotor voltage to eliminate the current errors at the end of the following sampling period. Space vector modulation is used to generate the required switching pulses within the fixed sampling period. The impact of sampling delay on the accuracy of the sampled rotor current is analyzed and detailed compensation methods are proposed to improve the current control accuracy and system stability. Experimental results for a 1.5-kW DFIG system illustrate the effectiveness and robustness of the proposed control strategy during rotor current steps and rotating speed variation. Tests during negative-sequence current injection further demonstrate the excellent dynamic performance of the proposed PCC method.
56.10.43	B. C. Rabelo, W. Hofmann, J. L. da Silva, R. G. de Oliveira, S. R. Silva, "Reactive Power Control Design in Doubly Fed Induction Generators for Wind Turbi," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 4154-4162, Oct 2009. Abstract Link Full Text Abstract: The high penetration level of wind power generation in an interconnected electrical network carries new technical challenges regarding system stability. Despite the stochastic nature of the wind, grid reliability has to be guaranteed. In compliance with power companies' new requirements on wind turbines as regards contribution to voltage regulation, this paper proposes a reactive power controller design for doubly fed induction generator drives. This drive topology enables the control of reactive power independently of the active power flow using both rotor and mains-side inverters. This degree of freedom is used in order to share the reactive powers circulating in the drive system and resulting from the reactive power required in the network. The controllers are designed using well-known linear control techniques in order to present the same dynamics. Furthermore, the proper reactive power share can be used to enhance the drive efficiency. Experimental results show the performance of the proposed reactive power control.
56.10.44	J. Arbi, M. J.-B. Ghorbal, I. Slama-Belkhodja, L. Charaabi, "Direct Virtual Torque Control for Doubly Fed Induction Generator Grid Connect," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 4163-4173, Oct 2009. Abstract Link Full Text Abstract: This paper presents a grid-connection control strategy of doubly fed induction generator wind system based on the direct control of both a virtual torque and rotor flux of the generator. This control is achieved with no proportional-integral regulator and requires the measurement of only grid voltages, rotor currents, and rotor position. The same switching table is used for grid synchronization and for running process. A field-programmable-gate-array-based design of the proposed control is developed and tested on a 4-kW experimental prototype. Experimental results are provided to show the effectiveness of the fast and soft grid-connection method developed.
56.10.45	D. G. Forchetti, G. O. GarcÍa, M. I. Valla, "Adaptive Observer for Sensorless Control of Stand-Alone Doubly Fed Induction Genera," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 4174-4180, Oct 2009. Abstract Link Full Text Abstract: A sensorless control strategy for a doubly fed (wound rotor) induction machine working in variable-speed stand-alone power systems without using mechanical sensors is presented in this paper. Stator voltage magnitude and frequency are regulated using two field-oriented control loops. A Luenberger observer is used to estimate the stator flux, while an adaptive scheme modifies the rotor position required in the stator flux estimation. Stator voltage magnitude and frequency control loops behave very well for steady state as well as for transient states like startup, speed variations, or electric load changes. Experimental results are presented to validate this proposal.
56.10.46	R. Pena, R. Cardenas, E. Reyes, J. Clare, P. Wheeler, "A Topology for Multiple Generation System With Doubly Fed Induction Machines and Indirect Matrix Conver," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 4181-4193, Oct 2009. Abstract Link Full Text Abstract: In this paper, a topology for a grid-connected generation system, based on two doubly fed induction machines, is presented. The proposed scheme is implemented using an indirect matrix converter (IMC) consisting of an input stage, a three-to-two matrix converter, and two output stages consisting of a pair of voltage source inverters. The input stage is connected to the grid and provides the required dc voltage for the output stages. Space vector modulation (SVM) is used for the input stage producing the maximum dc voltage, with unity power factor operation at the IMC grid-side input. Each of the output converters is connected to the rotor of a DFIM. The rotor currents of each machine are vector controlled for fast dynamic response and tight torque control. Moreover, the SVM algorithm used for the inverters is designed to provide soft switching operation in the input converter. Simulation and experimental results obtained from a 2.5-kW experimental prototype are presented. Steady-state and transient operation is discussed with the system running at below and above synchronous speed. The results demonstrate the feasibility of the proposed scheme for variable speed energy systems.
56.10.47	R. Cardenas, R. Pena, G. Tobar, J. Clare, P. Wheeler, G. Asher, "Stability Analysis of a Wind Energy Conversion System Based on a Doubly Fed Induction Generator Fed by a Matrix Conver," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 4194-4206, Oct 2009. Abstract Link Full Text Abstract: In this paper, the performance of a grid-connected wind energy conversion system (WECS), based on a doubly fed induction generator (DFIG) fed by a matrix converter (MC), is presented. The MC replaces the back-to-back converters conventionally used to control a DFIG. The MC is operated with closeto-unity power factor at the grid side. Stability issues related to the operation of the MC in the proposed WECS are discussed. A small signal model is used to investigate the dynamic performance of the two control arrangements discussed in this paper. Experimental results, obtained with a 4-kW prototype, are presented and fully discussed in this paper. The performance of the system for variable speed generation is verified using the emulation of a variable speed wind turbine implemented with a digitally controlled dc machine.
56.10.48	N. Patin, E. Monmasson, J.-P. Louis, "Modeling and Control of a Cascaded Doubly Fed Induction Generator Dedicated to Isolated Gr," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 4207-4219, Oct 2009. Abstract Link Full Text Abstract: This paper deals with the control of an autonomous cascaded doubly fed induction generator (CDFIG) operating in a variable speed constant frequency (VSCF) mode. The proposed structure is a full stand-alone generating system dedicated to isolated grids for embedded systems such as aircraft or small-scale renewable-energy systems such as microhydropower generators. Compared to a traditional VSCF system based on a single DFIG, CDFIG allows suppressing brushes, leading to an easier maintenance. However, the main difficulty when working with such a structure is its inherent complexity. The major issue is to synthesize an efficient global-control strategy for these two strongly connected machines. To overcome this problem, a modeling methodology based on dynamical equivalent circuits is given in this paper for the design of the CDFIG controller. Presented simulations and experimental results validate the proposed design approach.
56.10.49	S. Shao, E. Abdi, F. Barati, R. McMahon, "Stator-Flux-Oriented Vector Control for Brushless Doubly Fed Induction Genera," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 4220-4228, Oct 2009. Abstract Link Full Text Abstract: Brushless doubly fed induction generators (BDFIGs) show commercial promise for wind-power generation due to their lower capital and operational costs and higher reliability as compared with doubly fed induction generators. This paper presents a vector-control scheme for a BDFIG operating as a variable-speed generator. The proposed vector controller is developed on the power-winding stator-flux frame and can be used to control both the speed and the reactive power. The machine model and the control system are developed in MATLAB. The test results show that the proposed controller has good dynamic performance when changes in speed and reactive power are applied.
56.10.50	K. Rothenhagen, F. W. Fuchs, "Doubly Fed Induction Generator Model-Based Sensor Fault Detection and Control Loop Reconfigurat," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 4229-4238, Oct 2009. Abstract Link Full Text Abstract: Fault tolerance is gaining interest as a means to increase the reliability and availability of distributed energy systems. In this paper, a voltage-oriented doubly fed induction generator, which is often used in wind turbines, is examined. Furthermore, current, voltage, and position sensor fault detection, isolation, and reconfiguration are presented. Machine operation is not interrupted. A bank of observers provides residuals for fault detection and replacement signals for the reconfiguration. Control is temporarily switched from closed loop into open-loop to decouple the drive from faulty sensor readings. During a short period of open-loop operation, the fault is isolated using parity equations. Replacement signals from observers are used to reconfigure the drive and reenter closed-loop control. There are no large transients in the current. Measurement results and stability analysis show good results.
56.10.51	K. Rothenhagen, F. W. Fuchs, "Current Sensor Fault Detection, Isolation, and Reconfiguration for Doubly Fed Induction Generat," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 4239-4245, Oct 2009. Abstract Link Full Text Abstract: Fault tolerance is gaining growing interest to increase the reliability and availability of distributed energy sources. Current sensor fault detection, isolation, and reconfiguration are presented for a voltage-oriented controlled doubly fed induction generator, which is mainly used in wind turbines. The focus of this analysis is on the isolation of the faulty sensor and the actual reconfiguration. During a short period of open-loop operation, the fault is isolated by looking at residuals calculated from observed and measured signals. Then, replacement signals from observers are used to reconfigure the drive and reenter closed-loop control. Laboratory measurement results are included to prove that the proposed concept leads to good results.
56.10.52	J. Lopez, E. Gubia, E. Olea, J. Ruiz, L. Marroyo, "Ride Through of Wind Turbines With Doubly Fed Induction Generator Under Symmetrical Voltage D," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 4246-4254, Oct 2009. Abstract Link Full Text Abstract: This paper deals with the grid fault ride-through capability of doubly fed induction generators. These machines are very sensitive to grid disturbances. To prevent the damages that voltage dips can cause on the converter, most machines are equipped nowadays with a crowbar that short circuits the rotor. However, during the crowbar activation, the rotor converter must be disconnected, hence the power generated with the turbine is no longer controlled. In doing so, the crowbar impedes the wind turbine from carrying out the voltage stabilization required by most new grid codes. This paper proposes a novel control strategy that notably reduces the crowbar activation time. As a result, the control of the turbine might shortly be resumed and the turbine can furthermore supply a reactive power fulfilling the newest grid regulations. Experimental results of a complete system are included, demonstrating the viability of the proposed control. Special Section on Industrial Wireless Sensor Network
56.10.53	P. Neumann, L. Rauchhaupt, G. P. Hancke, "Guest Editor," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 4255-4257, Oct 2009. Abstract Link Full Text Abstract: Not Available Special Section Papers
56.10.54	V. C. Gungor, G. P. Hancke, "Industrial Wireless Sensor Networks: Challenges, Design Principles, and Technical Approac," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 4258-4265, Oct 2009. Abstract Link Full Text Abstract: In today's competitive industry marketplace, the companies face growing demands to improve process efficiencies, comply with environmental regulations, and meet corporate financial objectives. Given the increasing age of many industrial systems and the dynamic industrial manufacturing market, intelligent and low-cost industrial automation systems are required to improve the productivity and efficiency of such systems. The collaborative nature of industrial wireless sensor networks (IWSNs) brings several advantages over traditional wired industrial monitoring and control systems, including self-organization, rapid deployment, flexibility, and inherent intelligent-processing capability. In this regard, IWSN plays a vital role in creating a highly reliable and self-healing industrial system that rapidly responds to real-time events with appropriate actions. In this paper, first, technical challenges and design principles are introduced in terms of hardware development, system architectures and protocols, and software development. Specifically, radio technologies, energy-harvesting techniques, and cross-layer design for IWSNs have been discussed. In addition, IWSN standards are presented for the system owners, who plan to utilize new IWSN technologies for industrial automation applications. In this paper, our aim is to provide a contemporary look at the current state of the art in IWSNs and discuss the still-open research issues in this field and, hence, to make the decision-making process more effective and direct.
56.10.55	K. Al Agha, M.-H. Bertin, T. Dang, A. Guitton, P. Minet, T. Val, J.-B. Viollet, "Which Wireless Technology for Industrial Wireless Sensor Networks? The Development of OCARI Technol," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 4266-4278, Oct 2009. Abstract Link Full Text Abstract: In this paper, we present an industrial development of a wireless sensor network technology called OCARI: Optimization of Communication for Ad hoc Reliable Industrial networks. It targets applications in harsh environments such as power plants and warships. OCARI is a wireless-communication technology that supports mesh topology and power-aware ad hoc routing protocol aimed at maximizing the network lifetime. It is based on IEEE 802.15.4 physical layer with deterministic Media Access Control layer for time-constrained communication. During the nontime-constrained communication period, its ad hoc routing strategy uses an energy-aware optimized-link state-routing proactive protocol. An OCARI application layer (APL) is based on ZigBee application support sublayer and APL primitives and profiles to provide maximum compatibility with ZigBee applications. To fully assess this technology, extensive tests are done in industrial facilities at ElectricitÉ De France R&D as well as at Direction des Constructions Navales Services. Our objective is then to promote this specification as an open standard of industrial wireless technology.
56.10.56	J. Kjellsson, A. E. Vallestad, R. Steigmann, D. Dzung, "Integration of a Wireless I/O Interface for PROFIBUS and PROFINET for Factory Automat," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 4279-4287, Oct 2009. Abstract Link Full Text Abstract: Cost related to the wiring of sensors and actuators in the manufacturing industry is rapidly increasing with the number of field devices. Complex engineering as well as cable wear and tear are important factors. For over a decade, fieldbuses have been the dominating approach to simplify installation, reduce engineering efforts, and increase reliability at the field level. The next step in this process is to introduce wireless communication in certain problematic parts of the field network. In order to do this, a reliable real-time communication system, designed to cope with the harsh environments where factory automation systems are employed, is required. The Wireless Interface for Sensors and Actuators (WISA), with its two subconcepts WISA-power and WISA-com, is such a system. This paper discusses how the WISA concept can be efficiently integrated into wired field networks for factory automation—both state-of-the-art [Process Fieldbus Decentral Peripherals (PROFIBUS DP)] and new (PROFINET IO) networks. We propose amendments to WISA, which will improve the 802.11b/g coexistence and harmonize the integration of WISA for sensor/actuator communication in, e.g., PROFINET IO systems. The suggested improvements relate to both the radio protocol in order to improve coexistence with other wireless technologies as well as concepts for the integration of WISA into the field network of PROFINET/PROFIBUS.
56.10.57	Y. Ishii, "Exploiting Backbone Routing Redundancy in Industrial Wireless Syst," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 4288-4295, Oct 2009. Abstract Link Full Text Abstract: Industrial wireless applications must interoperate with backbone infrastructure for operation and monitoring by control systems. Most of these systems are designed with multiple backbone routers (BbRs) to enhance reliability. Multiple BbRs have a significant impact on wireless systems as the redundancy of multiple BbRs offers a number of benefits, such as spatial diversity and load balancing. Here, we investigate the advantages of spatial diversity provided by multiple BbRs. BbR-related communication patterns and mesh routing mechanisms optimizing the effects of spatial diversity are shown, and we also clarify the quantitative effectiveness of the redundancy of multiple BbRs with experimental proofs.
56.10.58	H.-S. Ahn, K. H. Ko, "Simple Pedestrian Localization Algorithms Based on Distributed Wireless Sensor Netwo," IEEE Trans. on Industrial Electronics, vol. 56, no. 10, pp. 4296-4302, Oct 2009. Abstract Link Full Text Abstract: This paper addresses simple algorithms for pedestrian localization based on the measurements from distributed wireless sensor networks (WSNs). It appears to be quite difficult to install a set of hardware sensors onto a human body; thus, traditional navigation sensors such as the inertial measurement unit cannot be employed for human tracking in a practical point of view. Recently, to minimize hardware installation onto the human body, WSNs have been actively investigated. However, there is a critical problem in WSNs associated with the measurement noises and signal disturbances. In this paper, we establish very simple localization algorithms that can reduce the noise effects as well as disturbances without a priori knowledge of them. Through actual experimental tests, the validity of the proposed methods is demonstrated.