What is the impact of the di/dt of EPS switching devices on EMC?

In EPS (Electric Power Supply), the di/dt (rate of change of current) of the switching devices directly affects its EMC performance. A high di/dt will generate induced voltage spikes (V=L*di/dt) on the parasitic inductance of the power circuit. These spikes are rich in high-frequency harmonics and are a significant source of conducted and radiated EMI. Specific effects include: increased differential-mode noise voltage; larger common-mode current coupled through the device's parasitic capacitance to ground; and strong near-field radiation caused by the corresponding high-speed changing magnetic field, interfering with surrounding sensitive circuits. To improve EMC, measures need to be taken to reduce the effective di/dt or absorb its energy, such as: optimizing the drive resistor to smooth the switching speed; connecting a ferrite bead in series in the current path or using a molded power inductor; adopting a multilayer busbar layout with low parasitic inductance; and designing effective snubber circuits.