In the modern power electronics industry, high-voltage static dynamic reactive power compensation device SVC is often used to eliminate reactive power, filter high-order harmonics, balance three-phase power grid, and improve the power supply environment of the power grid. TCR (Thyristor Controlled Reactor) is a main component of the thyristor-controlled reactor type SVC. Since a single TCR can only absorb inductive reactive power, it is often used in conjunction with a parallel capacitor FC. After the capacitors are shunted, the total reactive power is the net reactive power after the TCR and the parallel capacitor reactive power are cancelled. It is characterized by continuous adjustment of the reactive power of the compensation device.