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

Area of Science:

• Electrical Engineering
• Power Electronics
• Electromagnetic Compatibility

Background:

• Power Factor Correction (PFC) circuits are essential for meeting Electromagnetic Interference (EMI) and Total Harmonic Distortion (THD) standards in AC grid-connected converters.
• Input EMI filters are typically required to mitigate high-frequency noise injected into the grid from PFC circuits.

Purpose of the Study:

• To discuss and evaluate a low-conducted electromagnetic emission boost PFC circuit utilizing Sliding Frequency Modulation (SFM).
• To compare the performance of the SFM boost PFC against a conventional Constant Frequency Modulation (CFM) boost PFC.

Main Methods:

• Development of an analytical loss model for both SFM and CFM boost PFC topologies.
• Comparative analysis of SFM and CFM boost PFC circuits operating at 120 kHz with identical nominal power (300 W) and output voltage (383 V).
• Validation of analytical findings through simulations and experimental testing.

Main Results:

• The SFM boost PFC exhibits lower conducted EM emissions compared to the CFM boost PFC.
• The analytical loss model accurately predicts the performance differences between the two modulation techniques.
• Experimental and simulation results confirm the effectiveness of SFM in reducing EMI.

Conclusions:

• Sliding Frequency Modulation (SFM) offers a viable solution for designing boost PFC circuits with reduced conducted EM emissions.
• The proposed SFM boost PFC meets EMI and THD standards effectively.
• This approach provides an alternative to traditional input EMI filtering requirements.