| 摘要 |
PURPOSE:To cause short circuiting in the arbitrary phase adjusted at any point of the half wave voltage of an AC electric power source to be short-circuited and to facilitate the adjustment by applying DC bias to the voltage waveform of said power source. CONSTITUTION:A thyristor 11 for short circuiting is connected so as to cause inter-line short circuiting on the output side of an AC electric power source S to be short-circuited, and a rectifier circuit 4 is s connected as to rectify the output of the power source S and to supply the DC voltage smoothed by a capacitor C to a DC bias adjusting circuit 1 via a resistance R1. The output of the circuit 1 biasing the AC voltage of the power source S with the DC voltage supplied from the resistor R1 is supplied to a square wave generating circuit 2, by which a square wave is generated. When a manual signal and the delay pulse adjusted within the range of this square wave with the start point of said square wave as a reference point are generated simultaneously, a thyristor 11 for short circuiting the power source S is fired. Thereby, the short circuiting is caused in the adjusted arbitrary phase at any point of the half wave voltage of the power source S. |
