Abstract: A storage capacitor power supply adapted to be used as a power source for an electric vehicle. The storage capacitor power supply is equipped with a charging control circuit which stops charging when the voltage developed across the terminals of the capacitors reaches a given value. The charging control circuit can switch this voltage between at least two levels. In a power mode, the voltage is set to a higher value. In a long-life mode, the voltage is set of a lower value.

Abstract: Method and apparatus for quickly and efficiently charging an electric double layer capacitor. The capacitor is charged by a constant-current power supply which is preferably a current controlled output type switching power supply. To cause the voltage across the terminals of the capacitor to reach its working voltage in a short time, the capacitor is overcharged for a short time. Where the capacitor is charged with a solar battery, a constant-current output type switching regulator is interposed between the solar battery and the capacitor.

Abstract: An AC power regulator having a tap changer. The regulator comprises a transformer having taps and thyristors connected with the taps, respectively. The regulator further includes rectifiers, comparators having hysteresis and comparing the output signals from the rectifiers with a reference voltage, a priority processing circuit for selecting the signal to which the highest priority is given out of the output signals from the comparators, firing circuits for firing the thyristors, respectively, and zero voltage-detecting circuits for detecting the voltages between the terminals of the thyristors. When the detected voltages are all nonzero, the conducting thyristor is switched to the next thyristor.