中文摘要：

随机开关频率脉宽调制方法在较宽频率范围可以获得均匀的频谱特性,但在数字化矢量控制系统实现中,采样频率同步随机变化使得滤波器设计复杂,而且控制器的增益和调节器的设计需要随着采样频率的改变而变化,使得工程化实现困难。提出一种基于矢量控制系统的双随机调制策略,在固定采样周期和不变调节器系数的情况下,应用变延时技术在一个采样周期内计算下一个脉冲输出的延时时间,实现开关周期和零矢量时间的随机化。理论分析和试验结果表明,该方法具有更好的电流频谱特性,并且不影响矢量控制系统性能,通用性强。

英文摘要：

The uniform spectral characteristics are achieved in the whole frequency interval for the randomized switching frequency PWM method.However,the synchronous change of sample frequency and switching frequency makes the filter design complex,meanwhile the digital realization of engineering becomes difficult as the gain of controller and modulator vary with the sample frequency.A novel strategy of dual randomized modulation was presented by which the sample frequency and parameters of regulators could keep unchanged.The randomized switching period was formed with the interval of two output pulses.Zero vectors were randomized with the sample frequency and the average switching frequency was equal to sample frequency with some constraint.Theory analysis and experiment indicate that the method has better spectral characteristic and is easy to realize by vector control system.