Fuzzy Adaptive PI Controlled AC Drive System Based On DSP

High-performance adjustable voltage adjustable frequency (AVAF) control technology of AC motors has been widely applied in various fields such as industrial automation and electric appliance, etc. AC motor is a high-order, multivariable and strong coupling nonlinear system. Parameter reconstruct and coordinate transform is used to realize decoupling control for magnetization component and torque component of the stator current. However, the operating status of the motor is vulnerable to the effects of changes in the motor parameters. Furthermore, the parameter of the general PI speed controller is depended on the precise mathematical model of motor. So, speed control system performance is affected by the motor parameters change and environmental variables.In order to overcome above-mentioned problems, adaptive fuzzy PI speed controller is proposed to regulate the parameter of the fuzzy PI controller real-time online such that the speed control system has the strong adaptiveness and robustness. The simulation results indicate that AVAF control system based on the adaptive fuzzy controller has a virtue of fast response and small overshot.The hardware and software design of the AC drive test system is completed and the AC drive digital control system based on DSP is also built in this paper. Where, the hardware design is composed of DSP and EPM chip design and their peripheral components. The DSP chip is TMS320F2812, produced by corporation of TI, which has fixed point operation ability with 32 bits. The clock frequency of this DSP is up to 150MHz so that control precise and processing capacity of the adjustable speed control system is much improved. The IPM chip is utilized to achieve integration and miniaturization of the main circuit of the speed control system. On the other hand, the SVPWM modulation algorithm is developed as the core of software design. Modular design strategies of hardware and software are applied in different modules to complete the specific function.Finally, integrated debugging of hardware and software of the test system is done and the relevant tests is verified the effectiveness of the presented approach. The experimental result indicates that the experiment drive system can realize the FOC control of the induction machine.