Multi-resonance characteristics caused by high-frequency disturbances in switching-mode power converters

When a high-frequency periodic disturbance penetrates into the source voltage or the load current in a switching-mode power converter, a beat phenomenon arises and the output voltage oscillates at an extremely low frequency. This phenomenon occurs in case that the disturbance frequency approaches to the fundamental and the harmonics of the converter´s switching frequency. As a result, the multi-resonant frequency response is obtained in the high-frequency region. This paper presents the generalized analysis of the above multi-resonance characteristics by modifying the state-space averaging method, and confirms its validity by the experiment.