摘要 |
In the disclosed device, a square wave generator drives a network composed of a parallel resonant circuit in series with a series resonant circuit. The resonant frequency of the parallel resonant circuit is substantially equal to the fundamental frequency of the square wave voltage generator and lower than the resonant frequency of the series resonant circuit. The resonant frequency of the series resonant circuit is lower than the frequency of the third harmonic of the square wave voltage generator. A load coupleable to the parallel resonant circuit has a complex impedance which shifts the current at the fundamental frequency about 30 DEG relative to the fundamental square wave voltage. |