100 kHz SiC-MOSFET SAPF with Simple PI Regulator for Selective Harmonic Suppression

This paper presents a 100 kHz switching frequency shunt active power filter (SAPF), which is based on SiC-MOSFET and DSP TMS320F28377D. Compared to the mostly about 10kHz switching frequency SAPF, 100kHz switching frequency makes it easy to design the current loop controller and achieve higher control bandwidth. By adopting the simple PI regulator to design the current loop, appropriate parameters of PI regulator and current loop bandwidth are given. Recursive discrete Fourier transform (RDFT) is used to extract harmonics selectively. By analyzing the relationship between different switching frequencies and harmonic extraction accuracy, harmonic suppression characteristics are improved at 100 kHz switching frequency. Meanwhile, due to the use of SiC-MOSFET, SAPF can operate stably with a low loss. A 10kVA prototype using CREE SiC power module CCS050M12CM2 is set up to verify the validity of the design method.