Compound switch is the main switching component of reactive power compensation device.

The composite switch, which combines the magnetic holding relay and the thyristor switch skillfully, has the advantages of complementary advantages, low power consumption of the magnetic holding relay and zero crossing switching of the thyristor switch. It is an ideal switching element. This switching switch not only suppresses inrush current and avoids arcing, but also has low power consumption and does not need to install radiator and cooling fan.

The key to combine the two is that the timing coordination between them must be tacit. The thyristor switch is responsible for controlling the input and removal of the capacitor, and the magnetic holding relay is responsible for keeping the capacitor connected after the input. When the magnetic holding is put into operation, the thyristor switch will immediately exit the operation, so as to avoid the heating of the thyristor element. Composite switch is suitable for urban power grid, rural power grid, real estate and other occasions where the load changes slowly.