Rectifying circuit is a circuit that converts alternating current into DC power. Most rectifier circuits consist of transformer, rectifier main circuit and filter. It has been widely applied in the field of DC motor speed regulation, generator excitation regulation, electrolysis, electroplating and other fields. Rectifying circuit is usually made up of main circuit, filter and transformer. After 1970s, the main circuit is composed of silicon rectifier diodes and thyristors. The filter is connected between the main circuit and the load to filter out the AC components in the pulsating DC voltage. Whether the transformer is set or not depends on the specific condition. The function of the transformer is to match the AC input voltage and the DC output voltage, and to isolate the electrical isolation between the AC power grid and the rectifier circuit.
The function of the rectifier circuit is to convert the low voltage alternating current to the unidirectional pulsating DC, which is the rectifying process of the alternating current, and the rectifying circuit is mainly composed of the rectifier diode. After the rectifier circuit, the voltage is no longer alternating voltage, but a mixed voltage containing DC voltage and AC voltage. It is customarily called unidirectional pulsating DC voltage.