This paper proposes a chaotic pulse width modulation method to spread the power spectrum of an induction motor drive system. The chaos area λ = 0.99 in the bifurcation tree of the double tent mapping is used for generating the chaotic numbers. An 80C196 micro-controller is employed for generating the chaotic numbers and a triangular carrier with a chaotic frequency is produced using an 80C196 micro-controller and a MAX038 frequency modulator. The experiments are performed with a 1.5[kW] induction motor drive system under a 2.5[A] load condition. The experimental results show that the carrier, voltage/current and acoustic switching noise spectrum of the proposed method are dispersed over a chaotic frequency range with no specific frequency concentration. Especially, in terms of the harmonic spread effect of the acoustic switching noise in the frequency range below 10[kHz], we confirmed that the proposed method shows a slightly smoother distribution in the 5–9[kHz] frequency band than the random PWM (RPWM) method. Finally, the speed control characteristics of the proposed method were investigated by a simple V/F speed control experiment.

本文提出了一种混沌脉宽调制方法来扩展感应电机驱动系统的功率谱。双帐篷映射的分叉树中的混沌区域λ = 0.99 用于生成混沌数。使用80C196微控制器产生混沌数，使用80C196微控制器和MAX038频率调制器产生具有混沌频率的三角载波。实验是在 2.5[A] 负载条件下使用 1.5[kW] 感应电机驱动系统进行的。实验结果表明，所提出方法的载波、电压/电流和声学开关噪声频谱分散在混沌频率范围内，没有特定的频率集中。尤其，就低于 10[kHz] 频率范围内的声学开关噪声的谐波传播效应而言，我们确认所提出的方法在 5-9[kHz] 频带中显示出比随机 PWM (RPWM) 稍微平滑的分布方法。最后，通过简单的 V/F 速度控制实验研究了所提出方法的速度控制特性。