| 摘要 |
PURPOSE:To secure the time inverse voltage impressed upon element group increasing the maximum output frequency by a method wherein each unit of inverter unit group is time sharing controlled successively corresponding to output voltage of inverter at every half period. CONSTITUTION:The series circuit of unit inverters 2, 3 and the series circuit of unit inverters 5, 6 are connected to power rectifier 1 in parallel to supply the induction heating tank circuit 4 with power from the bridge point and the bridge point of DC condensers C1, C2. Then the negative half wave time of inverter output voltage is taken out by means of comparator 7 to control the frequency dividing circuits 14-17 through the intermediary of NOT gates 8, 12, 13, AND gates 10, 11 further transmitting gate signals to be time sharing controlled. Through these procedures, the period of inverse voltage impressed upon element group may be extended multiplying the specified maximum output frequency several times more than the conventional one. |
