Electrical – what’s is the good frequency for switching mode power supply


What’s the good frequency of switching mode power supply to have good efficiency?

Best Answer

It depends on the power level and how good is good. The power grid runs on 50/60 Hz although not switched for a reason.

GW HVDC substations switches at about 50-2000 Hz. MW traction converters for trains around 1 kHz. Multi kW-power supplies for inductrial applications around 5-10 kHz. kW level high end amplifiers and welding equipment at about 50-100 kHz. 100 W laptop chargers and the like at about 60-200 kHz. Small 10 W cell phone chargers at ~500 kHz. Integrated single-W converters inside computers and simular in the MHz region.