A discrete time variable structure controller for a brushless DCmotor drive

The design and the microprocessor-based implementation of a variable-structure-strategy (VSS) controller for a brushless DC motor drive are described. The controller is a conventional variable-structure design in the continuous-time domain. However, the microprocessor implementation using a constant sample period implies that full sliding mode is not achieved. The properties of the quasi-sliding that results are explored. It is shown that the sliding line expands into a sliding region, which can be described as a sector. The size of this sector is related to the sampling period and the switching gains. A modified design procedure is proposed for discrete-time VSS design. The design was verified on an experimental set-up, which generated variations in system parameters as well as external load disturbances     

New robust adaptive control algorithm for high-performance ACdrives

This paper presents a new robust structure for a model reference adaptive control (MRAC) controller for field-oriented-controlled (FOC) drives which requires no prior knowledge of the drive parameters and is guaranteed to provide global asymptotic stability of the closed-loop system. This structure simplifies the design and implementation of the adaptive controller requiring less effort to synthesis than a standard MRAC system. Discussion on theoretical aspects, such as selection of a reference model, stability analysis proof, gain adaptive process, steady-state error elimination, and robustness to unmodeled dynamics are included. The paper describes many practical aspects of the implementation, such as adaptive gain analysis, adaptive rate selection, the gain variation limits, gain windup prevention measure, and initial values. The new robust adaptive controller has been successfully implemented on an FOC drive and experiment results for dynamic tracking, sudden loading and unloading, and gains adaptation under different operation conditions are presented to support the robustness of the proposed controller     

A Stochastic-Based FPGA Controller for an Induction Motor Drive With Integrated Neural Network Algorithms

This paper applies stochastic theory to the design and implementation of field-oriented control of an induction motor drive using a single field-programmable gate array (FPGA) device and integrated neural network (NN) algorithms. Normally, NNs are characterized as heavily parallel calculation algorithms that employ enormous computational resources and are less useful for economical digital hardware implementations. A stochastic NN structure is proposed in this paper for an FPGA implementation of a feedforward NN to estimate the feedback signals in an induction motor drive. The stochastic arithmetic simplifies the computational elements of the NN and significantly reduces the number of logic gates required for the proposed NN estimator. A new stochastic proportional-integral speed controller is also developed with antiwindup functionality. Compared with conventional digital controls for motor drives, the proposed stochastic-based algorithm enhances the arithmetic operations of the FPGA, saves digital resources, and permits the NN algorithms and classical control algorithms to be easily interfaced and implemented on a single low-complexity, inexpensive FPGA. The algorithm has been realized using a single FPGA XC3S400 from Xilinx, Inc. A hardware-in-the-loop (HIL) test platform using a Real Time Digital Simulator is built in the laboratory. The HIL experimental results are provided to verify the proposed FPGA controller.     

A robust speed controller for induction motor drives

A speed controller considering the effects of parameter variations and external disturbance for indirect field-oriented induction motor drives is proposed in this paper. First a microprocessor-based indirect field-oriented induction motor drive is implemented and its dynamic model at nominal case is estimated. Based on the estimated model, an integral plus proportional (IP) controller is quantitatively designed to match the prescribed speed tracking specifications. Then a dead-time compensator and a simple robust controller are designed and augmented to reduce the effects of parameter variations and external disturbances. The desired speed tracking control performance of the drive can be preserved under wide operating range, and good speed load regulating performance can also be obtained. Theoretic basis and implementation of the proposed controller are detailedly described. Some simulated and experimental results are provided to demonstrate the effectiveness of the proposed controller     

Optimal controller design for a matrix converter based surface mounted PMSM drive system

This paper proposes a new control algorithm for a matrix converter permanent magnet synchronous motor (PMSM) drive system. First, a new switching strategy, which applies a backpropagation neural network to adjust a pseudo DC bus voltage, is proposed to reduce the current harmonics of the permanent magnet synchronous motor. Next, a two-degree-of-freedom controller is proposed to improve the system performance. The parameters of this controller are obtained by using a frequency-domain optimization technique. The controller design algorithm can be applied in an adjustable speed control system and a position control system to obtain good transient responses and good load disturbance rejection abilities. The controller design procedures require only algebraic computation. The implementation of this kind of controller is only possible by using a high-speed digital signal processor. In this paper, all the control loops, including current-loop, speed-loop, and position-loop, are implemented by a 32-b TMS320C40 digital signal processor. The hardware, therefore, is very simple. Several experimental results are shown to validate the theoretical analysis.     

Design and implementation of an adaptive controller for current-fedinduction motor

A model reference adaptive speed controller for a current-fed induction motor drive is proposed. The controller uses a proportional-integral (PI) adaptation to satisfy the hyperstability condition for load and machine parameter changes of the drive. Only the available information on the states and output of the reference model as well as the plant output are required. No explicit parameter identification is needed. The controller can be designed simply by using a reduced reference model without particularly degrading the performance, so it is easy to implement practically. The hardware implementation is detailed, and some experimental results are given to demonstrate its effectiveness     

High-Speed Control of IPMSM Drives Using Improved Fuzzy Logic Algorithms

This paper presents an improved fuzzy logic controller (FLC) for an interior permanent magnet synchronous motor (IPMSM) for high-performance industrial drive applications. In the proposed control scheme for high-speed operations above the rated speed, the operating limits of IPMSM are expanded by incorporating the maximum torque per ampere operation in constant torque region and the flux-weakening operation in constant power region. The power ratings of the motor and the inverter are considered in developing the control algorithm. A new and simple FLC is utilized as a speed controller. The FLC is developed to have less computational burden, which makes it suitable for real-time implementation, particularly at high-speed operating conditions. The complete drive is implemented in real-time using digital signal processor (DSP) controller board DS 1102 on a laboratory 1-hp IPM motor. The efficiency of the proposed control scheme is evaluated through both experimental and computer simulation results. The proposed controller is found to be robust for high-speed applications     

A simple direct-torque neuro-fuzzy control of PWM-inverter-fedinduction motor drive

In this paper, the concept and implementation of a new simple direct-torque neuro-fuzzy control (DTNFC) scheme for pulsewidth-modulation-inverter-fed induction motor drive are presented. An adaptive neuro-fuzzy inference system is applied to achieve high-performance decoupled flux and torque control. The theoretical principle and tuning procedure of this method are discussed. A 3 kW induction motor experimental system with digital signal processor TMS 320C31-based controller has been built to verify this approach. The simulation and laboratory experimental results, which illustrate the performance of the proposed scheme, are presented. Also, nomograms for controller design are given. It has been shown that the simple DTNFC is characterized by very fast torque and flux response, very-low-speed operation, and simple tuning capability     

一种太阳能供电LED照明系统电路设计

文章以太阳能供电的LED照明系统为研究对象,探讨了其基本构成,重点探讨了太阳能充电控制器的设计及其电路实现。设计了以PWM控制器CS51221为控制核心的充电控制器的电路,探讨了相关元器件参数的计算方法：分析了LED照明驱动系统的组成及其功能,设计了以NCP3066为核心的LED驱动电路、光敏二极管开关电路、PWM波调光电路;完成了简易太阳能供电LED照明系统电路的硬件,并对其功能及工作性能参数进行了测试和分析。结果表明,该LED照明系统满足设计要求,系统运行良好。     

CMOS drive and control circuitry for 1-10 MHz power conversion

The design, implementation, and experimental evaluation of CMOS subcircuits that can be combined to implement integrated control and drive for 1-10 MHz power circuits are presented. The approach taken is to develop controller/driver ICs for a specific prototype power converter. By maximizing the performance of the different subcircuits in successive design iterations, the fundamental questions about the viability of CMOS technology for high-frequency controller/driver applications can be answered. The ability of CMOS to satisfactorily perform at these high frequencies is documented     

Analysis and implementation of a real-time predictive currentcontroller for permanent-magnet synchronous servo drives

A real-time current controller for PWM inverter-fed permanent-magnet synchronous motor drives is presented and analyzed. The proposed current control scheme is based on predictive control with a parallel integral loop added to compensate for the inaccuracy of the motor model and for the variations of motor parameters and DC voltage source. The proposed current control scheme is analyzed and its performance is evaluated by computer simulation. An EPROM-based implementation is presented in which calculations and pulsewidth modulation are executed by lookup tables resulting in high-speed operation. The controller performance is evaluated using a prototype l kW PM synchronous servo drive. Experimental results are given and discussed     

Microprocessor implementation of a state feedback control strategyfor a current source inverter-fed induction motor drive

The realization of a microprocessor-based controller which implements a complete state-feedback control strategy for a current source inverter-fed induction motor drive is reported. The controller design is based on the application of the pole assignment technique of multivariable system regulation theory to a d,q-axis state-space linearized model of the drive and includes a reduced-order observer to achieve fast regulation and stability. The observer is designed to reconstruct the inaccessible states such as d,q -axis rotor current from a knowledge of the system inputs and outputs. The hardware and software implementation of the controller around an 8085-based microprocessor kit is discussed, and typical test results are presented, along with digital simulation results, to show its performance     

Variable structure current control for induction motor drives byspace voltage vector PWM

In this paper, a variable structure current controller based on a space voltage vector PWM scheme is presented for induction motor drives. In this current controller design, only the current sensors are employed and we attempt to force the stator currents to be exactly equal to the reference currents rapidly. This proposed current controller, which is based on the space voltage vector PWM drive, exhibits several advantages in terms of reduced switching frequency, robustness to parameter variations, elimination of current/torque ripple, and improved performance in induction motor drive. It shows that the current control laws can be demonstrated in theory. Finally, simulation and experimentation results verify the proposed control scheme     

Drive-Mode Control for Vibrational MEMS Gyroscopes

This paper presents a novel design methodology and hardware implementation for the drive-mode control of vibrational micro-electro-mechanical systems gyroscopes. Assuming that the sense mode (axis) of the gyroscope is operating under open loop, the drive-mode controller compensates an undesirable mechanical spring-coupling term between the two vibrating modes, attenuates the effect of mechanical-thermal noise, and most importantly, forces the output of the drive mode to oscillate along a desired trajectory. The stability and robustness of the control system are successfully justified through frequency-domain analysis. The tracking error between the real output and the reference signal for the drive mode is proved to be converging with the increase of the bandwidth of the controller. The controller is first simulated and then implemented using field-programmable analog array circuits on a vibrational piezoelectric beam gyroscope. The simulation and experimental results verified the effectiveness of the controller.     

Design and implementation of industrial neural network controller using backstepping

In this paper, a novel neural network (NN) backstepping controller is modified for application to an industrial motor drive system. A control system structure and NN tuning algorithms are presented that are shown to guarantee stability and performance of the closed-loop system. The NN backstepping controller is implemented on an actual motor drive system using a two-PC control system developed at The University of Texas at Arlington. The implementation results show that the NN backstepping controller is highly effective in controlling the industrial motor drive system. It is also shown that the NN controller gives better results on actual systems than a standard backstepping controller developed assuming full knowledge of the dynamics. Moreover, the NN controller does not require the linear-in-the-parameters assumption or the computation of regression matrices required by standard backstepping.     

Dynamic modeling and control of a conveyance microrobotic system using active friction drive

Presents a new generation of compliant multidegree of freedom piezoelectric microconveyer for microobjects based on the cooperation of arrayed direct-drive micro standing-wave ultrasonic actuators (microSWUMs). Their operating driving principles based on active frictional contact forces offer direct-drive and low-speed characteristics at the microscale. The tradeoff, however, is the complexity of dynamic modeling and control to cope with the optimization of the intermittent friction drive mechanism. A method using an equivalent electromechanical circuit is proposed for estimating and analyzing the optimum driving force, including the dynamic electrical and the mechanical energy conversions. On the basis of the proposed method, the friction drive optimization of the microrobot is performed through the implementation of different controllers: 1) an electromagnetic-field-based preload controller ensuring optimal preload; 2) an open-loop piecewise-modulated controller for self locking and driving force control; and 3) a resonant frequency compensation. Finally, an experimental investigation has been performed on a prototype of ultrasonic microconveyer incorporating 48 arrayed microSWUMs whose overall dimensions are 47 /spl times/ 29 mm/sup 2/ in order to demonstrate the proposed optimized friction drive.     

Sequential design of hysteresis current controller for three-phaseinverter

In this paper, a novel multivariable hysteresis current controller for three-phase inverters is presented. Hysteresis controllers are intrinsically robust to system parameters, exhibit very high dynamics, and are suitable for simple implementation. The main drawback of the hysteresis controller is a limited control on transistors' switching frequency. Very high switching frequency may result if three independent controllers are used. Multivariable solutions were proposed in the literature to solve the problem. In this paper, it is shown how the use of a sequential design for the multivariable controller can further contribute to transistors' switching frequency reduction, with no significant increase in the hardware implementation complexity. The proposed controller is illustrated and compared with other hysteresis controllers presented in the literature. It ensures a significant reduction of transistors' switching frequency with respect to the other tested controllers, under the same operating conditions. A prototype controller is also presented. The effects of noise captured by current sensors (especially Hall-effect type) on the performance of industrial hysteresis controllers are discussed. It is shown how the sequential design of the controller can also help in solving this critical problem. Experimental results are reported to confirm the quality of the proposed controller. The system stability condition is derived in an appendix     

Low Cost Gate Drive Circuit for MOSFETs and IGBTs

This work presents the design and implementation of a general purpose low cost drive circuit for insulated gate electronic power devices such as MOSFET and IGBT. The proposed drive circuit implementation is explained in detail and the results and waveforms obtained when the drive circuit is used in a chopper circuit with IGBT are presented.     

DSP-based self-tuning IP speed controller with load torquecompensation for rolling mill DC drive

This paper describes the design and the implementation of a self-tuning integral-proportional (IP) speed controller for a rolling mill DC motor drive system, based on a 32-bit floating point digital signal processor (DSP)-TMS 320C30. To get a better transient response than conventional proportional-integral (PI) and/or integral-proportional (IP) speed control in the presence of transient disturbance and/or parameter variations, an adaptive self-tuning IP speed control with load torque feedforward compensation was used. The model parameters, related to motor and load inertia and damping coefficient, were estimated online by using recursive extended least squares (RELS) estimation algorithm. On the basis of the estimated model parameters and a pole-placement design, a control signal was calculated. Digital simulation and experimental results showed that the proposed controller possesses excellent adaptation capability under parameter change and a better transient recovery characteristic than a conventional PI/IP controller under load change