Wan Shanming

Study on speed detection and control method of PMSM under ultra-low speed

The mathematical model of permanent magnet synchronous motor (PMSM) and the digital control method of current loop have been studied, including P regulator, P regulator plus feed forward control and PI regulator. And PI has the best performance. Under ultra low speed, the coupling of d axis current and q axis current do not exist, so the speed control system become a single input and single output system. The speed detection problem of PMSM has been studied also in this paper. The method of T and M/T speed detection will deteriorate the performance of the servo system under ultra-low speed. The M method is suitable for high speed and low speed range both. The deference of PLL and M speed detection method has been studied also. System software flowchart using TMS320F2812 is presented. The experiment results are given, and the validity of this theory is proved.

Hardware implement of numerical control system for bearingless induction motor

To realized the numerical control of three-phase bearingless induction motor, the unitary configuration of numerical control experimental system of three-phase bearingless induction motor has been designed firstly, then based on TMS320LF2407A numerical control CMOS chip of motor, the hardware control system configuration has been designed, and aiming at DSP operation and controller, high-speed photoelectricity seclusion and drive circuit, measuring and adjusting circuits for current and radial displacement, keyboard and display numerical control circuit, etc…, have been presented. The suspension control experiment results have verified the feasibility and practicability of the designed system.

Velocity Control Based on SDKF Estimation for PMSM Servo System

The angular velocity through first-order differential calculation of the position pulse data from photoelectric encoder have serious errors. Single-dimensional Kalman filter (SDKF)with adaptive systematic noise variance is proposed to estimate velocity, since the noise variance is associated with velocity and its variations. The simulation and experimental results demonstrate that the SDKF becomes succinct, and the filtered velocity becomes smooth without jump and obvious ripple phenomenon, which benefits the velocity control.

A stator resistance compensator for a direct torque controlled low speed and high torque permanent magnet synchronous motor

Nowadays, the research on low speed and high torque permanent magnetic synchronous machine more and more attention in the fields of motors, and has great science significance and application value. Direct torque control (DTC) has become an a accepted advanced control method beside the current vector control Although DTC was initially applied in asynchronous machines, but it has been introduced successfully to synchronous machines. This paper will discuss the DTC in the PMSM. With DTC, the electromagnetic torque and stator flux can be estimated using the measured stator voltages and currents. The estimation does depend on motor parameters except for the stator resistance. The variation of stator resistance due to changes in temperature or frequency degrades the performance of DTC controller by introducing errors in the estimated flux linkage vector and the electromagnetic torque. Compensation for the effect of stator resistance variation then becomes necessary. Estimation of the stator resistance and its compensation using a PI-fuzzy estimation has been proposed in this paper.

A Direct Torque Controlled Permanent Magnetic Synchronous Motor System Based on the New Rotor Position Estimation

The low speed and high torque permanent magnetic synchronous motor (PMSM) is increasingly playing an important role in electric propulsion system due to its many advantages over competing technologies. The direct torque control (DTC) technique for PMSM is receiving increasing attention due to the important advantages the low dependence on motor parameters when compared with other motor control techniques. But for successful operation of PMSM, rotor position and speed information is required. Thus, there has been an intense interest in the development of a so called position sensorless drive. In this paper, a adaptive estimation approach is developed which enable sensorless operation of the PMSM . Implementation issues for the sensorless PMSM electric drive are discussed,and experimental results are presented in order to demonstrate the effectiveness of the proposed techniques to the sensorless PMSM.

The adaptive control of three-degrees-of-freedom spherical motor

This paper presents the electromagnetic model and the mechanical model of three-degrees-of-freedom spherical motor (3DOFSM). The vector control and disturbance torque observer can realize the electromagnetic decoupling and mechanical decoupling control of the 3DOFSM. The adaptive scheme is proposed to improve the robustness and the dynamic performance. The correctness of the control scheme are confirmed by simulation results.