What is soft-switching technology

With the emergence of soft switching technology, the high frequency of switching power supply has been realized, which can not only reduce the volume and weight of the power supply, but also improve the efficiency of the switching power supply.

If the PWM switching power supply works in hard switching mode, during the switching process, the waveform will overlap in the process of voltage and current changes, so the switching loss is large, and the loss increases with the increase of the switching frequency. In order to solve this problem, in the 1980s, the technology of switching voltage/current waveform non-overlapping was developed, that is, the zero-voltage (ZVS) switching circuit and zero-current (ZCS) switching circuit generated by resonant technology, quasi-resonant technology or the combination of PWM and quasi-resonant technology, which is collectively referred to as soft switching technology. The use of soft switching technology, under ideal circumstances, can reduce the switching loss to zero, improve the efficiency, but also greatly reduce the electromagnetic interference, which also helps to further improve the switching frequency, so that the switching power supply further to the direction of small size, light weight, high efficiency, and high power density. At present, the efficiency of domestic switching power supply using soft switching technology has reached 93%.