High-response flux control of direct-field-oriented induction motorwith high efficiency taking core loss into account

Stator core loss has significant adverse effects when an induction motor is controlled by the conventional field-oriented method. Therefore, taking core loss into account should make it possible to control the torque very precisely. In this paper, a direct-field-oriented induction motor with a deadbeat rotor flux controller was developed. The method ensures maximum efficiency in the steady state without degradation of the dynamic response. Simulation and experimental results have demonstrated that this method has higher efficiency and good speed response without any degradation in the transient characteristics     

A speed-sensorless vector control method of parallel-connected dual induction motor fed by a single inverter

The purpose of this paper is to present the speed-sensorless vector control method of the torque production from each rotor of two induction motors with parallel-connected stator windings fed by a single inverter. In this paper, an adaptive rotor flux observer is applied to the method in order to eliminate a flux sensor, and an adaptive scheme for rotor speed is added to the adaptive rotor flux observer in order to eliminate a speed sensor. The experimental results show that the proposed method is useful under the condition that the ratings of each induction motor are different.     

异步电动机矢量控制中的转速辨识

介绍了异步电动机无速度传感器矢量控制中的转速辨识方法。基于电机的理想模型和瞬时无功功率理论,采用合适的控制方法,从定子电压电流中提取转子转速信息。给出了控制系统框图,并说明了理论和实际应用中需要解决的问题。     

Consideration about problems and solutions of speed estimation method and parameter tuning for speed-sensorless vector control of induction motor drives

A classical model-based speed-sensorless field-oriented control method for a general-purpose induction machine is considered. Improved versions of both speed and stator resistance online estimators are presented with the aim of extending control capabilities down to zero speed. Only electrical stator measurements are needed, making the method suitable for general-purpose inverter applications. Online rotor resistance tuning is also included to fully compensate for thermal drift. Performance of the proposed drive is investigated by simulation and experiments.     

A novel stator resistance estimation method for speed-sensorless induction motor drives

A method for online estimation of the stator resistance of an induction machine is presented and a speed-sensorless field-oriented drive equipped with the proposed estimator is built. The drive is particularly suitable for low-speed operation. Resistance estimation is based on a two-time-scale approach, and the error between measured and observed current is used for parameter tuning. The simple full-order observer in use allows for direct field orientation in a wide range of operation. The system can drive active load and generate stall torque, as confirmed by numerical simulations and experimental tests on a general-purpose 7.5 kW induction machine.     

High-performance speed-sensorless control of an induction motor drive using a minimalist single-phase PWM converter

Home appliances and comfort conditioners are yet to benefit from the recent developments in power electronics because of cost constraints. In this paper, a speed-sensorless induction motor drive system using converters with reduced device counts (minimalist, sparse converters) and actuated from a single-phase system is proposed for such low-cost applications. The analysis, control, dynamic, and steady-state characteristics of the proposed drive are experimentally illustrated.     

一种新型交流异步电机电压解耦矢量控制系统

提出了一种异步电动机电压解耦矢量控制系统的设计方法,详细分析了电压解耦矢量控制理论,确定了基于DSP控制技术的矢量控制系统硬件和软件结构,并将该系统左用于绞车传动中控制PWM变频器,并进行了实验。结果表明该设计系统合理,总体功能达到了矢量控制系统的技术指标。     

A real-time control platform for rapid prototyping of induction motor vector control

This paper presents a real-time control platform developed for rapid prototyping of an induction motor (IM) vector control. Firstly, the control system is designed with the Simulink in the form of user-friendly block-diagrams. Next, c-codes are automatically generated from the block-diagrams with the real-time workshop. And lastly, an executable code, produced from the c-codes through a DSP c-compiler, is downloaded into a target DSP board. With this automatic programming scheme rapid prototyping is realized with the least low-level handwork programming. Presented control platform has been evaluated through the rapid prototyping of a voltage source inverter-fed IM driver and some experiments have been carried out to show its effectiveness.     

大功率感应电机矢量控制系统软硬件设计

根据大功率感应电机矢量控制的特点,设计了一种基于浮点型数字信号处理器ＴＭＳ３２０Ｃ３１和单片机８０Ｃ１９６ＭＣ的双微机矢量控制系统,并详细说明了其软硬件设计方法。实验结果表明,该控制系统充分利用了ＴＭＳ３２０Ｃ３１和８０Ｃ１９６ＭＣ的特点,软硬件设计合理、实时性好,能可靠地完成复杂的矢量运算和优化 ＳＰＷＭ波形生成,控制感应电机达到较好的动态性能。     

异步电动机无速度传感器的矢量控制

对交流异步电动机无速度传感器的矢量控制进行了综述 ,分析了几种控制方案的原理 ,指出了它们各自的优点与不足 ,并就今后的研究发展方向提出了一些设想     

Direct torque control, induction motor vector control without anencoder

The basic evolution of direct torque control from other drive types is explained. Qualitative comparisons with other drives are included. The basic concepts behind direct torque control are clarified. An explanation of direct self control and the field-orientation concepts implemented in the adaptive motor model block is presented. The reliance of the control method on fast processing techniques is stressed. The theoretical foundations for the control concept are provided in summary format. Information on the ancillary control blocks outside the basic direct torque control is given. The implementation of special functions directly related to the control approach is described. Finally, performance data from an actual system are presented     

Principles of modeling transformer transients taking into account topology and magnetic core features

A method describing processes in cold-rolled steel and reproducing dynamic hysteresis loops in certain core components (legs and yokes) is proposed. A method that takes into account magnetic fluxes in a nonmagnetic medium that makes the transformer model reversible is described. Transients initiated by sub-sequent energizing of a three-phase group of four-limb transformers in a 500-kV network are simulated.     

基于转差率的感应电机最优效率控制

针对感应电机的能量优化问题,提出了一种基于转差率的感应电机最优效率控制方法和算法,用于恒压频比(VVVF)感应电机驱动系统,并给出仿真结果。该方法具有明显的节能效果。     

Optimizing the operating modes of cogeneration stations taking actual state of main equipment into account

A software system is developed that allows the operating conditions of a cogeneration station to be optimized taking into account the actual state of main equipment estimated from the values of parameters measured at different points of the technological circuits of steam boilers and turbines.     

无速度传感器异步电机矢量控制系统的改进研究与仿真

以异步电机矢量控制的基本方程式为基础,构建了一个无速度传感器矢量控制系统。系统采用了改进积分型转子磁链估算模型。根据模型参考自适应方法的原理,提出一种改进的速度估算法。并利用MATLAB/SIMULINK进行了仿真,仿真结果验证了采用的速度估算方法是正确的。     

Speed sensorless vector control of induction motor using extendedKalman filter

A vector control of an induction motor by an estimated speed using an extended Kalman filter is proposed. With this method, the states are composed of stator current and rotor flux. The rotor speed is regarded as a parameter, and the composite states consist of the original states and the rotor speed. The extended Kalman filter is employed to identify the speed of an induction motor and rotor flux based on the measured quantities such as stator currents and DC link voltage. The estimated speed is used for vector control and overall speed control. Since the current control is performed at a synchronous rotating reference frame, the estimated speed information is also used for the reference frame transformation of the current controller. Computer simulations and experiments of the speed control have been carried out to test the usefulness of the speed estimation algorithm. The experimental results show that the performance of the speed estimation is very good     

Performances of fuzzy-logic-based indirect vector control for induction motor drive

This paper presents a novel speed control scheme of an induction motor (IM) using fuzzy-logic control. The fuzzy-logic controller (FLC) is based on the indirect vector control. The fuzzy-logic speed controller is employed in the outer loop. The complete vector control scheme of the IM drive incorporating the FLC is experimentally implemented using a digital signal processor board DS-1102 for the laboratory 1-hp squirrel-cage IM. The performances of the proposed FLC-based IM drive are investigated and compared to those obtained from the conventional proportional-integral (PI) controller-based drive both theoretically and experimentally at different dynamic operating conditions such as sudden change in command speed, step change in load, etc. The comparative experimental results show that the FLC is more robust and, hence, found to be a suitable replacement of the conventional PI controller for the high-performance industrial drive applications.     

Achieving more efficient control of boilers by taking technological constraints into account

The structure of a nonlinear system for control the superheated steam temperature taking technological constraints into account is considered. A solution is proposed that allows a larger stability margin of the automatic closed-loop control system to be obtained. The influence of additional tuning parameters on the quality of control is shown. The use of proposed solution makes it possible to make the control process more accurate and smooth, to take into account technological constraints, and achieve robustness of the control system with respect to coordinate and parametric disturbances.