Development of Sensorless PMSM Drives: Application of Extended Kalman Filter

Abstract

This paper describes in detail guidelines for the development of fixed-point control systems with the main emphasis on the sensorless drives, presents the approaches used in the stage of fixed-point simulation as well as approach for the verification of the microprocessor code. The presented development method significantly speed-ups control system prototyping and increases the reliability of microprocessor code. The described design process is documented on the sensorless control system based on the extended Kalman filter (EKF), which is very difficult for the fixed-point implementation. This paper presents and compares different structures of EKF that can be employed in PMSM drives without either speed or position sensor. I. INTRODUCTION The most of the industrial control systems employ the fixed-point microcontrollers. The development, imple- mentation and debugging of the fixed-point control systems and especially development of sensorless techniques, which often introduce complex computational problems, requires special skills from the researcher. The specific problems of the fixed-point implementation together with the trend to reduce time-to-market have to be respected already in the stage of control system simulation. Therefore, the aim of this paper is to present development method, which can significantly speed-up control system prototyping and increases the reliability of the microprocessor code. The described design process is in this paper illustrated on the development of the sensorless control system of PMSM machine with surface magnets based on the extended Kalman filter (EKF) that represents very complicated problem for fixed-point implementation. II. ROTOR SPEED AND POSITION ESTIMATION USING