Low Conducted-EMI Single-Phase Boost PFC with Sliding Frequency Modulation

A boost Power Factor Correction (PFC) circuit is connected between the AC grid and converters to meet Electromagnetic Interference (EMI) and Total Harmonic Distortion (THD) standards. An EMI filter should be utilized at the input of the PFC to attenuate high-frequency noise injected into the grid. This article discusses the low-conducted EM emission boost PFC with Sliding Frequency Modulation (SFM) proposed by Power Integrations. The proposed boost PFC is compared with a conventional boost PFC operated using Constant Frequency Modulation (CFM) at 120 kHz. Both PFCs are rated for the same nominal power (i.e., 300 W) and output voltage (i.e., 383 V). An analytical loss model is also developed to compare the performance of the SFM and CFM PFCs. The analytical findings are verified by means of simulations and experiments.