What is the principle of switching power supply work

Switching power supply is a kind of power supply, which can convert AC power into DC power, and can control the size of the output voltage and current. Its working principle is: first, the alternating current is converted into high-voltage direct current through a transformer, and then the high-voltage direct current is filtered through a filter to filter out the high-frequency noise, and then the filtered direct current is regulated by a switching tube to regulate the voltage to the required voltage, and finally the regulated voltage is regulated by a voltage regulator circuit to regulate the voltage to the required voltage to realize the control of the output voltage.