Monaco the switching frequency of the AC-DC switching power supply module?(2)
Monaco Choosing the switching frequency of the Marine boost/buck voltage power supply does not mean choosing the switching frequency of the Marine boost/buck voltage 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 Marine boost/buck voltage 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
Drive module power supply
The frequency converter power supply is mainly used for the frequency conversion and speed regulation of the AC motor. The main circuit of the inverter power supply adopts the AC-DC-AC scheme. The power frequency power supply becomes a fixed DC voltage through a rectifier, and then a PWM high-frequency converter composed of high-power transistors or IGBTs inverts the DC voltage into an AC output with variable voltage and frequency. The output waveform of the power supply is similar to a sine wave. It is used to drive the AC asynchronous motor to realize stepless speed regulation.
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 Marine boost/buck voltage power supply equipment will be reduced to the maximum, which is not conducive to miniaturization. When the switching Marine boost/buck voltage 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.