The selection rule of the hysteresis width has been developed in order to make the THD and RMS value of the output voltage to be the best with high efficiency, according to the principle of pulse density modulation.

• 根据脉冲密度调制技术的原理导出了使输出电压失真度最小、有效值最大，系统效率也较高的环宽取值公式。