LFM-Based PWM Strategy for Switching Ripple Communication and Harmonic Reduction

Switching ripple communication technology adopts output voltage ripples as information carriers, which establishes information exchange between devices without any extra hardware circuits. On the other hand, electromagnetic compatibility (EMC) is also an important issue during the design of power electronic converters. To achieve these two goals, a pulse width modulation (PWM) strategy based on linear frequency modulation technology is proposed in this paper, which integrates the communication technology of linear frequency modulation with the PWM process of power electronic devices. The proposed strategy employs linear frequency modulation (LFM) signals as carriers for both power and information. By modulating information onto the starting frequencies of the Chirp signals, information transmission is achieved while switching harmonics are suppressed through frequency dispersion. The proposed method has been implemented in a Buck converter, and simulation results verify its effectiveness.