Singapore the switching frequency of the AC-DC switching power supply module?(2)

The high-voltage DC power supply for electrostatic precipitator has been developed in China. The commercial power is rectified into DC, and the full-bridge zero-current switch series resonant inverter circuit is used to invert the DC voltage to a high-frequency voltage, which is then boosted by a high-frequency transformer, and finally rectified. for DC high voltage. Under the condition of resistive load, the output DC voltage reaches 55kV, the current reaches 15mA, and the operating frequency is 25.6kHz.

Singapore Choosing the switching frequency of the 48V input power supply does not mean choosing the switching frequency of the 48V input power supply with a good switching frequency, but the choice is suitable for your own use. Most of the current market is like this. The frequency of the AC-DC switching 48V input power supply module is between 50K and 135K, and this frequency range can meet most applications. Let's discuss it. Some of the problems that AC-DC encounters when choosing switching frequency:

1. Why generally do not choose a switching frequency lower than 50K

We know that the lower the switching frequency, the smaller the switching loss, but on the other hand, with the reduction of the switching frequency, the volume of the 48V input power supply equipment will be reduced to the maximum, which is not conducive to miniaturization. When the switching 48V input power supply is working, due to the switching of the switching device, the magnetic core will vibrate, and the frequency range that the human ear can hear is about 20~20000Hz. In order to avoid audible noise, we usually choose to stay away from the 20 frequency KHz.