What is the relationship between PCSdv/dt overshoot and radiated EMI in energy storage systems?

Overshoot of dv/dt (voltage change rate) in PCS and the resulting ringing are directly related to excessive radiated EMI (RE). Excessive dv/dt itself generates broadband noise, while overshoot ringing produces strong narrowband noise peaks at specific resonant frequencies determined by parasitic LC. These high-frequency voltage oscillations radiate outwards like antennas through chassis gaps, unshielded cables, etc., easily leading to RE test failures in the 30MHz-1GHz band. Suppressing dv/dt overshoot is key to reducing RE. Methods include: connecting an RC snubber circuit in parallel across the switching transistor; using an RCD or active clamping snubber circuit; optimizing the drive circuit impedance and layout to reduce parasitic inductance; and selecting newer devices such as freewheeling diodes or SiC MOSFETs with softer recovery characteristics.