Study on Drive and Control System of Five-Phase PMSM Based on FPGA
|School||Harbin Institute of Technology|
|Course||Motor and electrical|
|Keywords||FPGA Five-Phase PMSM SVPWM SPWM|
On the background of the research for the Multi-phase Permanent Magnet Synchronous Motor (PMSM) system, this study researchs the FPGA based drive and control system of five-phase PMSM. Though the three-phase drive system will be used for a very long time due to the economical of regularization and standardization of manufacture, its traditional dominate status has been challenged in many applications. In the case of low voltage high power and high availability drive applications, Multi-phase motors have showed more advantages over traditional three-phase motors, such as motors used for water circulation in nuclear power station, drive system of hybrid vehicles, air navigation and space faring, ship electrical propulsion. Therefore, the study of multi-phase motors has been concentrated by more and more people.Firstly, the MMF time-space harmonics distribution of symmetrical multiphase windings is analyzed, the qualification for creating rotary MMF in multiphase windings is indicated; math modeling of five-phase PMSM with sinusoidal windings and third harmonic inserted windings are then developed, the Generalized Park Transformation is derived and its physics meaning is clearly indicated, then Park Equation is built in rotary frame. All of above lay the theoretical foundation for studying the method of multiphase motors control.Secondly, two different vector control methods are proposed for two different structure five-phase PMSM control systems based on the former analysis of MMF harmonics and math models, a developed control method is proposed for the sinusoidal windings five-phase PMSM, and a method of inserting third harmonic current to enhance torque density of multiphase motor control system is proposed for the third harmonic inserted windings five-phase PMSM, the amplitude and phase qualification is given out. These two control methods are compared and simulated in Simulink.Thirdly, the PWM schemes for two different structures are investigated. The space vector pulse width modulation is adopted in sinusoidal windings five-phase PMSM vector control system, the traditional SVPWM algorithm is analyzed and its disadvantage of low DC voltage utilization is pointed out, then a optimal SVPWM algorithm is proposed; then this SVPWM algorithm’s applicability to third harmonic inserted windings five-phase PMSM control system is discussed and is proved unsuitable for this application, finally, a SPWM scheme is adopted.At last, a third harmonic inserted windings five-phase PMSM is designed, hardware platform of its control system is constructed, software code based on FPGA is written, and the vector control method proposed in this study is validated. The experimental results indicate that with third harmonic current and third harmonic rotor magnetic field inserted, the torque density of five-phase motor is improved, the motor drive system can get high power output ability in low voltage application cases.