基于扫频校正的 PMSM 电流环精准带宽设计方法研究

In order to improve the design accuracy of permanent magnet synchronous motor (PMSM) current loop bandwidth and to overcome the shortcoming that model-based tuning extremely dependent on model parameter accuracy, this paper proposed an improved tuning method, which takes the closed-loop bandwidth as the design index and has capability of parameter self-adaptive correction. Firstly, by introducing the gain coefficient γ, physical relationship between delay and PI parameters was established. Secondly, an open-loop frequency sweep correction method was proposed to solve the actual delay of the system with the least squares fitting algorithm, thereby reducing the loss of tuning accuracy caused by the delay modeling error. In addition, a closed-loop frequency sweep correction method was proposed, which can effectively reduce the error caused by resistance and inductance mismatch between controller and the motor. Finally, the effectiveness and universality of the proposed method were verified by multiple motor experiments on the physical platform. The relative error of the tuning was less than 5% and the time domain response of multiple motors was consistent.