| 摘要 |
<p>PURPOSE:To improve the reliability of a test by providing a center tap to the secondary winding of a transformer and connecting a breaker for voltage control and an impedance element between the secondary winding and the capacitor of a voltage source circuit. CONSTITUTION:One terminal side of the secondary winding of the transformer 5 is connected to one terminal side of the capacitor 6 through the breaker for voltage control, the center tap is provided to the secondary winding of the transformer 5, and the impedance element 8 composed of, for example, a resistance is connected between the center tap and a point A. Then the secondary voltage of the transformer 5 which is applied to one terminal side of the capacitor 6 after breaking of primary breaking phase is switched at a point of time corresponding to breaking of the 2nd breaking phase. Consequently, while the rise rate of a recovery voltage is held high, its crest value is reduced and a waveform approximating the waveform of a voltage applied to the 1st breaking phase of a three-phase circuit is obtained. Thus, a reliable test is conducted and a 60Hz system can be tested by using a power source of 50Hz.</p> |
