Vector-controlled induction motor drive with a self-commissioningscheme

Different vector-controlled structures are discussed, and their suitability for an economical and reliable industrial drive system is explored. From this, the design of a compact control hardware is derived, composed of an 80196 microcontroller and an ASIC (application-specific integrated circuit) for the generation of the pulsewidth modulation (PWM) signals. The drive system can be configured from a host computer or a hand-held servicing unit through a serial data link. Monitoring and diagnostic functions are included. A self-commissioning scheme permits the setting of the parameters for optimum dynamic performance of the induction motor. Various oscillograms demonstrate the behavior of the vector controller operating a 25-kVA PWM inverter     

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.     

Robust speed control of an induction motor: an /spl Hscr//sub /spl infin// control theory approach with field orientation and /spl mu/-analysis

In this paper we present a robust speed control strategy for an induction motor under field orientation. The control framework employed properly represents the induction motor state-space model and its inherent variations, which are treated as structured uncertainties. Applying an /spl Hscr//sub /spl infin//, optimization methodology on this framework we derive a stabilizing controller to meet design objectives and then robust stability and performance against such variations are checked by using /spl mu/-analysis. No on-line tuning is required for the parameters of the derived controller, which is the dynamic system responsible to keep the rotor flux orientation as well as the speed regulation at design levels, irrespective of the motor operating points. A general methodology arose from the usage of the proposed strategy and simulated experiments showed satisfactory results for the robust speed control of an induction motor.     

An MRAC-based nonlinear speed control of an interior PM synchronous motor with improved maximum torque operation

A model reference adaptive control (MRAC)-based nonlinear speed control strategy of an interior permanent magnet (IPM) synchronous motor with an improved maximum torque operation is presented. In most servo systems, the controller is designed under the assumption that the electrical dynamics are neglected by the field-oriented control. This requires a high-performance inner-loop current control strategy. However, the separate designs for a high-performance current regulator and a robust speed controller need considerable effort. To overcome this limitation, an MRAC-based nonlinear speed control strategy for the IPM synchronous motor is presented, considering the whole nonlinear dynamics. Nonlinear speed control is achieved by an input–output linearization scheme. This scheme, however, gives an unsatisfactory performance under the mismatch of the system parameters and load conditions. For the robust output response, the controller parameters are estimated by an MRAC technique in which the disturbance torque and flux linkage are estimated. The adaptation laws are derived from Lyapunov stability theory. In view of the drive efficiency, the motor has to provide the maximum torque for a given input. To drive the IPM synchronous motor under improved maximum torque operation, the estimated flux linkage is employed for the generation of the d-axis current command. The robustness and output performance of the proposed control scheme are verified through simulation results.     

基于STM32的无刷直流电机控制器硬件电路设计及实验研究

以STM32F103C8T6为核心,设计了无刷直流电机控制器硬件电路。电路主要包括IR2310构成的PWM驱动电路、IRF3808构成的逆变电路、增量式旋转编码构成的速度反馈电路。控制器具有CAN和RS232通信接口,可与计算机或PLC构成速度或位置伺服系统。利用由xPC目标搭建的半实物仿真平台对PI参数进行整定。测试了控制器的速度伺服响应性能,给定速度为2400rpm时,控制器响应时间为0.32s。实验结果表明,系统工作可靠,稳定性好,响应速度快,可以满足上肢康复机器人要求。     

Comparing the indirect field-oriented control with a scalar method

Two methods of induction motor control are examined. The indirect field-oriented (IFO) and the slip-control (SC) methods are formally compared. Their block diagrams are derived, analyzed and their similarities shown. It is demonstrated that the difference between the two is just due to a feedforward block that computes the current phase to be supplied to the motor in an IFO controller. This proves that the implementation complexity of either controller is almost identical. To perform comparative tests, both control methods were implemented using a single hardware. The torque rise time and frequency response of the speed control are presented. Based on experimental results, it is shown that the speed sensor resolution and the sampling rate of the controller strongly influence the dynamic response in the IFO method. The SC method is less sensitive to these parameters although it always presented a worse dynamic response. The IFO speed control presented a flat frequency response whereas the SC method presented a peak which could lead to an oscillatory speed response. It is also shown that the variation of the rotor electrical time constant influences strongly and in a similar way both control methods. Finally, it can be concluded that the implementation complexity of both control strategies are almost identical, although the IFO control method has a much better performance than the SC control method.<>     

Integrated design of speed-sensorless and adaptive speed controller for a brushless DC motor

The study develops a design of an integrated new speed-sensorless approach that involves a torque observer and an adaptive speed controller for a brushless dc motor (BLDCM). The system is based on the vector control drive strategy. The speed-sensorless approach first employs a load observer to estimate the disturbed load torque, and then the estimated load torque is substituted into the mechanical dynamic equation to determine the rotor speed, and thus develop a speed-sensorless algorithm. Additionally, the mechanical rotor inertia constant and the friction coefficient, which are the inputs of the load observer, are estimated using the recursive least-square rule. Therefore, the proposed speed-sensorless approach is unaffected by the time-variant motor parameters nor is affected by the integrator drift problem. It also has a simpler computing algorithm than the extended Kalman filter for estimating the speed. The modified model reference adaptive system algorithm, an adaptive control algorithm, is adopted as a speed controller of the BLDCM to improve the performance of the speed-sensorless approach. Simulation and experimental results confirm that the performance of the design of a new integrated speed-sensorless approach and the adaptive speed controller is good.     

A nonlinear speed control for a PM synchronous motor using a simpledisturbance estimation technique

A nonlinear speed control for a permanent-magnet (PM) synchronous motor using a simple disturbance estimation technique is presented. By using a feedback linearization scheme, the nonlinear motor model can be linearized in the Brunovski canonical form, and the speed controller can be easily designed based on the linearized model. This technique, however, gives an undesirable output performance under the mismatch of the system parameters and load conditions. An adaptive linearization technique and a sliding-mode control technique have been reported. Although good performance can be obtained, the controller designs are quite complex. To overcome this drawback, the controller parameters are estimated by using a disturbance observer theory where the disturbance torque and flux linkage are estimated. Since only the two reduced-order observers are used for the parameter estimation, the observer designs are considerably simple and the computational load of the controller for parameter estimation is negligibly small. The nonlinear disturbances caused by the incomplete linearization can be effectively compensated by using this control scheme. Thus, a desired dynamic performance and a zero steady-state error can be obtained. The proposed control scheme is implemented on a PM synchronous motor using a digital signal processor (TMS320C31) and the effectiveness is verified through the comparative simulations and experiments     

Novel motors and controllers for high-performance electric vehiclewith four in-wheel motors

We have, in accordance with new concepts, undertaken the development of a high-performance electric motor vehicle, designated as the IZA. The main performance features of the IZA are a maximum speed of 176 km/h, a range of 548 km per charge at a constant speed of 30 km/h, and acceleration from 0 to 400 m in 18 s. We have developed a direct driving in-wheel motor and controller in order to achieve high performance characteristics. The in-wheel motor is composed of an outer rotor with a rare earth permanent magnet (Sm-Co) and an inner stator. The motor drive controller consists of a three-phase inverter and a microprocessor-based controller. The maximum output and maximum torque of each total drive system, including motor and inverter, are 25 kW and 42.5 kg·m, respectively, and the total efficiency of the drive system is over 90% at the rated speed. The performance of the motor, controller, and drive system have been confirmed by numerous simplex and vehicle transit tests. This paper describes the design concepts, configuration, and performance of the motor, controller, and drive system developed for this high-performance electric vehicle     

Design and implementation of a high-performance field-orientedinduction motor drive

The design and implementation of a high-performance controller for a field-oriented induction motor drive is presented. Dynamic modeling based on the stochastic technique is performed. Based on the estimated drive model, a two-degree-of-freedom controller is proposed so good dynamic responses in both the speed tracking and regulation characteristics can be achieved. The parameters of the controller are found using a proposed systematic design procedure according to the prescribed specifications. Having designed and tested the performance of the controller by simulation, the hardware implementation is successfully made, and some experimental results are given to demonstrate the effectiveness of the proposed controller     

Design of an Adaptive Controller for Microcomputer Implementation

A design procedure for an adaptive controller is described and applied to the design of a velocity controller for small dc motors. The basic concept has been to determine a small set of controllers each of which is capable of maintaining stability and acceptable performance over a specific region of motor load parameters. Optimal control theory is used to define the control coefficients while cluster analysis and decision function techniques from pattern recognition theory are used to determine each controller's region of applicability. Simulation results are presented to verify performance improvements using the design procedure. The design procedure produces an adaptive controller which is computationally feasible for implementation in small microcomputer systems.     

A self-commissioning algorithm for VSI-fed induction motors

In the paper, a self-commissioning algorithm is presented, which allows the determination of the parameters of an induction motor fed by a VSI, without any additional hardware, with respect to the one required by a vectorial control strategy. It is based upon the comparison between the measured and the predicted current response of the motor to an adequate feeding voltage waveform. The algorithm can be easily implemented as a start-up routine of the control software. In this way, a precise and quick evaluation of the motor parameters can be achieved. The validity and feasibility of the proposed algorithm are proved by experimental implementation.     

A multiprocessor-based fully digital control architecture forpermanent magnet synchronous motor drives

The design and implementation of a multiprocessor-based fully digital control architecture for permanent-magnet synchronous motor drives and an approach for designing advanced AC servo drives using currently available high-performance microprocessors are presented. The design of the architecture involves formulation of control algorithms for a current-regulated pulsewidth-modulated inverter and advanced vector-control strategies for speed and position loop. Under the vector-control framework, some recently developed robustness control results are applied to the design of speed-loop controllers. The implementation of the architecture integrates the control of current, speed, and position loop using the multiprocessor-based controller. Experimental case studies that correlate simulation and measurement results are provided. Experiments were conducted to compare the controller performance, including step speed and position responses, closed-loop frequency responses, the effect of field-weakening control, and disturbance-rejection performance. The experimental results validate the theoretical development     

基于模糊自适应PID控制的速度调节器设计与仿真

针对异步电动机非线性的特点,考虑到传统PID控制难以对其进行有效的控制的问题。文中设计了一种模糊自适应PID控制器,并将这种控制器应用到系统的转速调节的环节中。利用Matlab的Simulink工具搭建了模糊自适应PID控制的异步电机的仿真模型。仿真实验结果证明了设计的优越性,模糊自适应PID控制下的系统超调变小,反应速度变快,与原先的PID控制方式相比提高了系统的稳定性、动态响应性能以及鲁棒性能。     

A VSS speed controller with model reference response for inductionmotor drive

This paper is mainly concerned with the development of a variable-structure system (VSS) controller with model reference speed response for an induction motor drive. An indirect-field-oriented (IFO) induction motor drive is first implemented, and its dynamic model at a nominal operating condition is estimated from measured data. Then, a two-degrees-of-freedom linear model-following controller (2DOFLMFC) is designed to meet the prescribed tracking and load regulation speed responses at the nominal case. As the variations of system parameters and operating condition occur, the prescribed control specifications may not be satisfied further. To improve this, a VSS controller is developed to generate a compensation control signal to reduce the control performance degradation. The proposed VSS controller is easy to implement, since only the output variable is sensed. The existence condition of sliding-mode control is derived, and the chattering suppression during the static period is also considered. Good model-following tracking and load regulation speed responses are obtained by the designed VSS controller. Effectiveness of the proposed controller and the performance of the resulting drive system are confirmed by some simulation and measured results     

Robust current controller for three-phase inverter usingfinite-state automaton

A novel feedback current controller for a three-phase load driven by a power inverter is proposed. The main design specifications are robustness to load electrical parameters, fast dynamical response, reduced switching frequency, and simple hardware implementation. To meet previous specifications a multi-variable hysteresis type controller is proposed, designed as a finite-state automaton and implemented with a programmable logic device. After a general introduction, system analysis is performed, control targets are specified, and the proposed control strategy is presented and discussed. Further, actual controller architecture, based on simple analog-logic hardware, is shown and experimental results are presented using an induction motor as the inverter load. However, this does not limit the wider applicability of the proposed controller that is suitable for different types of three-phase AC loads     

A high-performance sensorless indirect stator flux orientation control of induction motor drive

A new method for the implementation of a sensorless indirect stator-flux-oriented control (ISFOC) of induction motor drives with stator resistance tuning is proposed in this paper. The proposed method for the estimation of speed and stator resistance is based only on measurement of stator currents. The error of the measured q-axis current from its reference value feeds the proportional plus integral (PI) controller, the output of which is the estimated slip frequency. It is subtracted from the synchronous angular frequency, which is obtained from the output integral plus proportional (IP) rotor speed controller, to have the estimated rotor speed. For current regulation, this paper proposes a conventional PI controller with feedforward compensation terms in the synchronous frame. Owing to its advantages, an IP controller is used for rotor speed regulation. Stator resistance updating is based on the measured and reference d-axis stator current of an induction motor on d-q frame synchronously rotating with the stator flux vector. Experimental results for a 3-kW induction motor are presented and analyzed by using a dSpace system with DS1102 controller board based on the digital signal processor (DSP) TMS320C31. Digital simulation and experimental results are presented to show the improvement in performance of the proposed method.     

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     

惯性变化时无刷直流电机的鲁棒控制器设计

为了获得良好的无刷直流电机调速性能,提出了一种基于Q参数化理论的控制器设计方法。该方法的主要特点是被控对象的所有稳定控制器均可用一个独立的Q参数来描述。仿真结果表明:在系统参数发生变化的情况下,在参考速度和负载转矩发生改变时,本文提出的控制策略都具有很好的响应特性。     

永磁同步电机的双闭环调速系统设计

永磁同步电机因其优越的性能近年来得到了广泛应用。针对双闭环控制器参数整定困难所导致的控制效果不佳的问题,文中提出了基于极点配置和Ramp函数的改进型双闭环PI控制器。从永磁同步电机矢量控制算法的角度出发,建立了速度、电流双闭环解耦控制的系统模型,并在此模型下论述了速度环、电流环控制器的设计方法,给出改进后双闭环控制器参数的计算结果。对所研究方法分别进行了计算机仿真和实际试验,结果表明优化后的系统减小了系统过冲,缩短了稳定时间,提高了系统动态响应,具有良好的工程意义。