Silicon controlled rectifier positive and negative semi-cycle turn-on circuit

The utility model discloses a silicon controlled rectifier alternate positive and negative half-cycle conduction circuit, which comprises a working circuit, a control circuit and a light silicon controlled rectifier IC2, and is characterized in that the working circuit is connected with the control circuit through the light silicon controlled rectifier IC2; the working circuit comprises a first working circuit and a second working circuit, the first working circuit comprises a silicon controlled triode Q1 and a diode D4, and the second working circuit comprises a silicon controlled triode Q2 and a diode D3; by arranging the first working circuit and the second working circuit, the silicon controlled triodes Q1 and Q2 work in turn during working, so that the silicon controlled triodes Q1 and Q2 respectively share half power, and the design purpose of ensuring that the silicon controlled triodes Q1 and Q2 operate at the working temperature without additionally arranging a radiator is achieved in the original wo