| 摘要 |
An inverter circuit for driving a load including an inductive component such as an inductive cooking appliance, and being powered by a pulsating DC source obtained by rectifying a single phase AC power input. The inverter includes a pair of power transistors operating in a push pull mode with a multiple winding transformer, and operating at a frequency in excess of the AC power line frequency. Alternate switching of the power transistors is fed back through the transformer to control the switching of the transistors. The improved circuit provides positive switching of the power transistors at the higher frequencies regardless of the fluctuations in amplitude of pulsating DC power input, by triggering the generation of constant firing pulses from a fixed voltage source to the transformer windings in a feedback arrangement. A starting oscillator is also provided to initially start, or restart, the inverter; and the starting oscillator is automatically decoupled from the inverter when the inverter is operating. In an alternative embodiment, the starting oscillator also provides the function of positively switching the power transistors after the inverter is functioning by changing its mode of operation from an oscillating circuit to a pulsing circuit.
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