Gao Hanying

Study on three-phase four-leg control technology of permanent magnet synchronous motor in electric vehicle

The permanent magnet synchronous motor (PMSM) has many advantages, such as high energy density, high efficiency and high power factor, and its application in electric vehicle is rapidly expanding. The traditional main circuit structure of three-phase three-leg topology with the space-voltage vector pulse width modulation (SVPWM) technology can reduce the winding harmonic currents and meanwhile improve the utilization rate of the DC voltage, thus reduce the torque ripple of the motor and broaden the speed range of motor effectively. However, in a-phase fault, the system reliability will be difficult to be maintained by the traditional topology structure. Therefore, it is limited on some occasions where reliability is strictly required, such as highway traffic, aviation, marine and explosion-proof, etc. On this basis the paper puts forward a three-phase four-leg control system with the fault-tolerant function. Namely, on the basis of traditional three-phase four-leg control system, the fourth leg is added and connected to the motor neutral point, and three dimensional voltage space vector modulation (3D-SVPWM) technique is utilized to drive PMSM, which make PMSM has a good running characteristics and can guarantee system safe and reliable running in the case of the lacking phase or the one-phased open-circuit fault, and in the aspect of electric vehicle drive has higher application value.

Simulation study on a DTC system of PMSM

In order to improve the dynamic performance of PMSM, a Direct Torque Control (DTC) scheme of Permanent Magnet Synchronous Motor (PMSM) is presented. Based on in-depth analysis of PMSM mathematical model and the operation principle of DTC system, Matlab / Simulink is used to establish a simulation model of this system, and extensive research of simulation is conducted. A large number of simulation results show that the DTC System of PMSM has fast response and good dynamic performance, which verify correctness and feasibility of this system.

Redundant Control Technology Based on Four-Leg Topology of Permanent Magnet Synchronous Motor

Permanent Magnet Synchronous Motor (PMSM) has many advantages, such as high energy density, high efficiency and high power factor, etc. This paper focuses on the research on a four-leg topology of PMSM motor, which is able to produce the same torque as before faulted through properly control strategy. Three dimensional voltage space vector modulation (3D-SVPWM) technique is utilized to drive PMSM, which make PMSM has good running characteristics and can guarantee system safety and reliability running in the case of the lacking phase or the one-phased open-circuit fault. Furthermore, the one-phased open-circuit fault is simulated, proving the motors fault-tolerant function and the feasibility of the control strategy.

Study on three-phase four-leg PMSM control system

The permanent magnet synchronous motor (PMSM) has many advantages, such as high energy density, high efficiency and high power factor, and its application field is rapidly expanding. The traditional main circuit structure of three-phase three-leg topology with the space-voltage vector pulse width modulation (SVPWM) technology can reduce the winding harmonic currents and meanwhile improve the utilization rate of the DC voltage, thus reduce the torque ripple of the motor and broaden the speed range of motor effectively. However, in a-phase fault, the system reliability will be difficult to be maintained by the traditional topology structure. Therefore, it is limited on some occasions where reliability is strictly required, such as aviation, aerospace, marine and explosion-proof, etc. On this basis the paper puts forward a three-phase four-leg control system with the fault-tolerant function. Namely, on the basis of traditional three-phase four-leg control system, the fourth leg is added and connected to the motor neutral point, and three dimensional voltage space vector modulation (3d-SVPWM) technique is utilized to drive PMSM, which make PMSM has a good running characteristics and can guarantee system safe and reliable running in the case of the lacking phase or the one-phased open-circuit fault.

Simulation of three-phase three-wire shunt APF with one-cycle control under double-direction compensation by PSCAD/EMTDC

In the light of the DC component existing in active power filter (APF) based on traditional one-cycle control strategy, one-cycle control under double-direction compensation control strategy is presented. One-cycle control under double-direction compensation shunt APF is designed, which is used in three-phase three-wire system. APF with resistive inductive load is simulated by PSCAD/EMTDC. Simulation results show that the proposed control method not only can eliminate the harmonic and reactive current effectively but also can eliminate the DC component. This control method provides theoretical and experimental guide for the application of APF.