基于永磁同步电机转子位置变化的混合开关频率调制技术

Hybrid Switch Frequency Modulation Technology Based on Rotor Position Change of Permanent Magnet Synchronous Motor

以电动汽车驱动用永磁同步电机为研究对象,提出一种新型混合开关频率调制策略,对其电压源逆变器的高频边带谐波电流优化进行了研究。首先,基于空间矢量脉宽调制(SVPWM)技术基本原理与实现方式,建立了响应的Matlab/Simulink仿真模型,分析了高频边带谐波电流产生机理。其次,基于电机转子电角度位置变化提出了新型混合开关频率调制策略,以减少电压源逆变器工作过程中产生的谐波成分,优化边带谐波电流响应。最后,通过合理设定电机参数,对电机稳态运行过程中的逆变器开关频率进行在线调节以降低谐波电流及其相应的扩展频谱。仿真过程中进一步对固定开关频率、传统随机开关频率及新型混合开关频率控制策略的边带谐波电流进行了对比分析。结果表明,相比于传统随机调制策略,所提出的新型调制技术对开关频率及其倍频附近的边带谐波成分有较好的抑制效果,进而验证了所提出方法的有效性。

Taking the permanent magnet synchronous motor(PMSM)for electric vehicle drive as the research object,a novel hybrid switching frequency modulation strategy was proposed.The high-frequency sideband harmonic current optimization of its voltage source inverter was studied.Firstly,based on the basic principle and realization mode of space vector pulse width modulation(SVPWM)technology,the Matlab/Simulink simulation model of response was established,where the generation mechanism of high-frequency sideband harmonic current was analyzed.Secondly,based on the electrical angle and position of the rotor,the novel hybrid switch frequency modulation strategy was proposed to reduce the harmonic components generated in the process of the voltage source inverter,together with the current harmonic optimization.Finally,with the reasonable setting the parameters of the prototype PMSM,the switching frequency during the steady-state operation of the motor was adjusted online to reduce the harmonic current and the corresponding frequency spectrum.In the simulation process,the comparisons among with the fixed,the traditional random and the novel hybrid strategy were carried out and analyzed.As the results shown,compared with the traditional random modulation strategy,the proposed modulation has a significant impact on suppressing the sideband harmonics around the switching frequency and its multiple,which verifies the effectiveness of the proposed method.