The Research On Intellectualized System Of Induction Motor Variable Frequency Speed Regulating

This paper develops an full digital induction motor vector control platform based on DSP which is related to the subject of Natural Science Fund of Hunan Province "The Research on the System of High Peformance Intelligentized Induction Motor Variable Frequency Speed Regulating", and presents the software and hardware design scheme. The upper computer is industry control computer, and the lower is DSP control board and transducer main circuit, then the motor control method is realized through the assembly language in DSP. In the practice, on the one hand the upper computer can observe the wave and understand the condition of the motor on running, on the other hand it can control the lower in starting, stopping and variable revising, at last the system output the PWM waves to control the induction motor. Varied high performance motor control algorithms can be realized on this platform and the experimental research in this paper is also put up on it. On theoretic aspect, a kind of sensorless induction motor vector control system based on adaptive flux observer is brought forward. The method is easy and can estimate the speed exactly; meanwhile, the speed following performance is quite good. However, because the math model of induction motor is complex, non-linear, time changing and coupling, the simulation result shows that the performance of the system using PID speed controller is not very satisfying which is strongly affected by the varying parameter and exterior disturbing. Thus, fuzzy control is introduced and a king of sensorless induction motor vector control system based on adaptive fuzzy controller is presented in which the traditional PID controller is replaced by the adaptive fuzzy controller. This controller adjusts the de-fuzzy parameter dynamically on the basis of outside condition and consequently has good adaptability. Compared with the sensorless vector control system using traditional PID controller, the system has better dynamic performance and smaller still difference, more it converges rapidly. The ability of robustness and anti-jamming has been improved greatly.