Implementation and simulation of various vector controlled induction motor drives
The development of AC drives has gained momentum with the advancement of power electronic devices, control theory and technology of microprocessors. Based on high speed digital signal processing theory and power transistor hardware, two axis machine model and adaptive control techniques, a vector controlled fully digital induction motor drive is a high performance, low cost drive which is becoming increasingly popular in many industrial applications in all power ranges and will succeed the dc drive in the near future. The main goal of the thesis is to investigate the various forms of implementations of vector controlled digital signal processor based high performance induction motor drives. For this purpose, a TMS320C30 digital signal processor board with transducer and interfacing circuits has been designed, manufactured and built. Furthermore a conventional bipolar transistor inverter has been modified and interfaced to the DSP board. The entire hardware has been tested and successfully implemented. The control software is versatile and provides a platform for implementing various control configurations. The first part of the thesis reviews the development of various vector controlled drives; different mathematical models are presented and discussed together with digital simulation results of different vector controlled schemes. Intelligent control algorithms based on neural networks, fuzzy control, self-tuning control are also considered, some of them are tested by using real-time simulation or on a real drive. Different PWM strategies are investigated and compared, and a versatile and reliable real-time PWM algorithm is generated and integrated into the drive control software. Various parameter identification and auto-commissioning techniques are included in the control software. Details of experimentally obtained results for various vector drives are presented.