device for the supply of a variety of oscillatory circuits through an inverter - power grid

摘要

In a typical application, to an induction cooker hob, energy is available at e.g. two locations. The energy source (1) is the rectified mains supply, driving an oscillator (2) employing two bipolar transistors (TA, TB) - optionally, thyristors, FET, or IGBT devices - series-connected across the supply. Each transistor has a freewheel diode (DA, DB) and a commutating capacitor (CA, CB), and the midpoint (J) is connected to e.g. two parallel resonant, RLC load circuits (I1, C11, C12; I2, C21, C22), controlled by on/off switches (K1, K2). By closing one switch only the oscillator output is made available to one inductor only. With both switches closed the energy distribution between inductors varies as the source frequency is brought closer to or further from the resonant frequency of one or other load circuit. In a variant, the resonant frequency of one circuit is also made variable, using switched capacitors, providing even greater flexibility.