永磁同步电机-空调压缩机系统的无传感器过调制控制

Sensorless over-modulation control of PMSM-compressor systems

为了改善永磁同步电机驱动空调压缩机系统在高速区的运行性能和可靠性,研究并开发了一整套控制方案。该方案采用一种双模式过调制算法,以提高脉宽调制(PWM)逆变器的电压利用率和永磁同步电机在高速区的输出转矩能力;采用模型参考自适应方法估计转子位置,以实现无位置传感器控制,同时实现了弱磁控制以提高电机转速。在一台永磁同步电机驱动的空调压缩机系统上进行了实验验证。采用该方法,使PWM逆变器的电压利用率平均提高了25%,且在高速运行时压缩机系统转速振荡幅度小于2.5%。结果表明:采用该控制方案,在电源电压一定的情况下,可提高电机定子电压和输出转矩能力,实现空调压缩机系统的高速稳定运行。

Control strategies were developed to improve the performance and reliability of high speed PMSM-compressor drives. A double mode over-modulation method enhances the voltage transfer ratio of the PWM inverter and the output torque of the PMSM during high speed operation. A model reference adaptive system （MRAS） is used to estimate the rotor position to realize sensorless drive. Rotor flux weakening is employed to obtain the high rotor speed. Tests on an air-conditioner compressor for an electric vehicle showed that the voltage transfer ratio of the PWM inverter was increased by about 25% by this sensorless over-modulation method. The speed fluctuations of the compressor are limited to 2.5% during high speed operation. The results demonstrate that these control strategies enhance the PMSM stator voltage/output torque capability and improve high speed operation of an air-conditioner compressor.