Transfer Function Model Based Analysis of Permanent Magnet Synchronous Motor with Controllers

Abstract: Permanent Magnet Synchronous Machine (PMSM) drives have been increasingly applied in a wide variety of industrial and mechatronics applications over other conventional drives. The reason comes from the advantages of PMSM: high power density and efficiency, high torque to inertia ratio, and high reliability. In this paper, the study and the design analysis of controllers and controller methods for PMSM is given. An existing BLDC motor for an electric forklift benchmarks the expected performances of the PMSM design. In the first part there is account working principle and design of PMSM. Mathematic model of PMSM is used for calculation for behavior of PMSM. Later, the mathematical modeling of PMSM has been done through Transfer Function approach. Later, obtained transfer function was subjected to controller approach which determines the performance of the PMSM. Initially, the Zeiglers-Nicholas PID controller method is used to determine the PMSM performance by two different sub controllers of ZN say, ZN-PI and ZN-PID Controllers. Next to this method, Pole Placement Technique is used for comparison of ZN-PI, PID. Characteristic Ratio Assignment (CRA) method is also used to determine the PMSM performance which was the main area of interest. This CRA method is solved with specimen problems initially and then solved for the transfer function that is derived in earlier stage. To know the performance of PMSM, CRA-PID controller is chosen in this thesis work. This method is mainly based on Pole Placement Technique. And it works on transient response of the transfer function. For the extension to this work, Fuzzy PI Logic Controller is also used to compare with CRA method. Finally, the specimen simulation problem is also performed in order to determine the speed, torque and current characteristics.

Keywords: Permanent Magnet Synchronous Motor, Charateristic Ratio Assignment method, Fully Logic controller, PID controller.