Thyristor is commonly known as silicon controlled thyristor. The difference between a thyristor and a diode is that it can control on and off. A represents the anode, K represents the cathode, and G represents the control electrode.

1. The conduction of the thyristor: the anode A is connected to a high potential, the cathode K is connected to a low potential, and the gate G is connected to the control terminal. When the thyristor is connected to the circuit, the thyristor will not conduct without adding a trigger signal to the gate.
   When the gate gets the trigger signal, the thyristor immediately turns on and maintains it. At this time, the gate trigger signal is removed, and the anode and cathode continue to be in a conductive state.
2. Turning off the thyristor: If the thyristor is to be turned off in the on state, two conditions must be met:
   a. The current through the thyristor is reduced to an unsustainable state and turns off by itself. This is called natural turn-off.
   b Applying a reverse voltage to the cathode and anode to turn it off, which is called forced turn-off.
3. Basic parameters of thyristor: a forward and reverse non-conducting voltage, b on-state average current, c on-state saturation voltage drop, d gate trigger voltage, e gate trigger current, f off time, etc. .
4. Classification of thyristors: They can be roughly divided into two categories according to their uses. a. The thyristors used in rectifier circuits are called KP, K represents the first letter of the pinyin of the thyristor, and P represents the first letter of the ordinary thyristor. letter. bThe thyristor used in the inverter circuit is called KK. The first K represents the thyristor, and the second K represents fast. Combined with our intermediate frequency furnace, there is KP for rectification and KK for inverter.