The control circuit of the designed 2.5KHz∕250KW induction heating furnace is a current-voltage double-closed loop control. The current is the inner loop and the voltage is the outer loop control mode.

Control circuit of 2.5KHz∕250KW induction heating furnace

In the figure, the given voltage is the load feedback voltage, and the load is given current, which is the load feedback current. Α is the conduction angle of the three-phase full-controlled rectifier bridge, and the control of the load power is realized by controlling the three-phase full-controlled rectifier bridge of the main circuit.