Induction heating apparatus using a saturable reactor for power control purposes

摘要

An induction heating apparatus includes a saturable reactor having a pair of rectangular ferrite cores. An air gap is provided in each ferrite core to provide a gradually increasing saturation characteristic on the magnetization curve of the cores. A pair of series-connected load windings is coiled around each core and a control winding is coiled around a common magnetic path of the cores. A power control circuit produces a DC control current that passes through the control winding. The high frequency energization current is passed through the load windings. Means are provided to control the DC control current at a desired setting. Preferably, the actual power level is detected to control the DC current through a feedback loop.