High-performance Intelligent Induction Motor Speed Regulation System

This paper focuses its emphasis on the digital control of induction motor, one of the most important aspects of the high-performance variable-frequency variable-speed system of induction motor. Based on the mathematical model of induction motor, this paper discusses the rotor-field-orientated control principium and the space vector pulse width modulation principle. Subsequently the software design of SVPWM is put forward. The software and hardware design of the DSP-based digital induction motor vector control system are always expounded in the chapter of system realization. The hardware design includes these main circuits such as current sensing, DC bus voltage sensing, space-vector PWM waveform generation, the system protection and so on. In the design of system software, we take account of the numerical format considering a fixed-point DSP TMS320F240, the software designs of the current model and software SVPWM model, and the online realization of parameters setting and changing in PC. After analyzing the software and hardware reasons which can affect the system performance when rotor speed is low, accordingly the improving methods are advanced. According to the system experimentation, it can be concluded that the reliability and stability of the system are all improved by using high-speed digital signals processor. Furthermore, the dynamic performance of the controller is more satisfying. Considering that only the conventional sensored vector control is realized in our system owing to the limitation of the hardware, this paper also discusses the speed-sensorless vector control in virtue of MATLAB/SIMULINK. In that chapter, a estimating method of rotor speed combining the neural network and the model reference adaptive system is brought out. The simulation result indicates that the speed-sensorless vector control system of induction motor using designed neural network estimator can get better performance.