永磁同步电机无位置传感器全速域控制方法

Sensorless Control Method for Permanent Magnet Synchronous Motor in Full Speed Domain

摘要:

为提高永磁同步电机在全速域无位置传感器控制的精度，设计了一种高频方波信号注入和基于转子磁链的改进滑模观测器相结合的复合控制方法。首先，在零、低速段采用脉振高频方波信号注入，通过简单的代数运算分离高频电流信号和基波电流信号，避免了在提取转子位置信息过程中使用滤波器，提高了转子位置观测的精度；然后，中、高速段采用改进的滑模观测器法，在滑模观测器中引入基于转子转速的自适应反馈增益，再利用转子磁链来提取转子位置信息，进一步提升了电机运行稳定性和控制精度；最后，采用加权函数对零、低速和中、高速的控制策略进行切换，从而构建全速域控制算法，该算法分别在带载启动、全速域运行和带速重投工况下进行仿真验证。仿真结果表明，所设计的全速域控制算法在不同工况下均能实现电机稳定高效的全速域运行，具有较好的动态性能和稳定性。

Abstract:

In order to improve the precision of sensorless control of permanent magnet synchronous motor in full speed domain, a composite control method combining high-frequency square wave signal injection and improved sliding mode observer based on rotor flux is designed. Firstly, the high-frequency square wave signal of pulse vibration is injected in zero and low speed sections, and the high-frequency current signal and fundamental current signal are separated by simple algebraic operation, which avoids the use of filter in the process of extracting the rotor position information, and improves the accuracy of rotor position observation. Secondly, the improved sliding mode observer method is used in medium and high speed sections with the introduction of adaptive feedback gain based on rotor speed, and then the rotor flux is used to extract the rotor position information, which further improves the running stability and control accuracy of the motor. Finally, the weighted function is used to switch the control strategies of zero, low speed and medium, high speed, so as to construct the full speed domain control algorithm. This algorithm is simulated and verified under the loaded startup, full speed domain running and restart at coasting condition respectively. The simulation results show that the designed full speed domain control algorithm can achieve the stable and efficient full speed domain running of motor under different working conditions, which has good dynamic performance and stability.