基于改进滑模观测器的永磁同步电机无位置传感器I/F起动方法

Sensorless I / F startup based on modified sliding mode observer for PMSM

针对传统的永磁同步电机无位置传感器开环起动过程中存在启动电流大、功率因数小、抗负载扰动能力弱的问题,提出了一种基于改进滑模观测器的无位置传感器电流闭环I/F起动策略。起动加速阶段,在电枢绕组中产生幅值固定、频率逐渐增大的旋转电流矢量,使转子加速起动。当转速达到设定值时,检测指令位置角与用改进滑模观测器估算的转子位置角之间的偏差角,当该偏差角低于设定的阈值时,立刻切换至基于改进滑模观测器的无位置传感器电流解耦控制阶段。仿真和实验结果表明,采用所提起动策略后,起动电流可控,切换时刻的电流、转矩平稳无冲击。实验结果也验证了该起动策略能有效避免过流的产生,具有良好的动态性能和一定的抗负载扰动能力。

A sensorless close loop I/F startup strategy based on the MSMO（Modified Sliding Mode Observer） is proposed for PMSM（Pcrmanent Magnetic Synchronous Motor） to avoid the problems of its sensorless open loop startup strategy,such as high startup current,small power factor and poor anti-load-disturbance ability. At the acceleration stage,the rotor is started up and accelerated by the rotating current vector with constant amplitude and gradually increasing frequency in armature winding. When the rotor speed reaches the setting value,the angle deviation between the reference angle and the angle estimated by MSMO is monitored. Once the angle deviation is lower than the threshold,the acceleration stage is switched over to the MSMO-based sensorless decoupled current control stage. Simulative and experimental results show that, with the proposed startup strategy,the startup current is controllable,and the current and torque at mode- switching moment are bumpless and stable, verifying its good dynamic performance and anti-load- disturbance ability.