| 摘要 |
PURPOSE:To prevent a failure in operation, an accident, etc., due to the unstable voltage of electric equipment, by varying the voltage transformation ratio of a transformer according to variation in power supply voltage, and holding the output of the transformer nearly constant. CONSTITUTION:A switching element part 26 consists of plural switching elements which are provided in the same number as respective circuits of a voltage detecting circuit part 7 corresponding to the various change of transformation ratios of a transformer, and a control circuit part 25 selectively operates a switching element corresponding to the output state of the circuit part 7. Then the circuit part 25 gives priority to the output of the circuit part 7 for detecting a maximum voltage value at that point, and puts one of switching elements of the element part 26 in operation. Then, control is so performed that at least after a switching element in operation is turned off, switching elements operate successively, and the voltage transformation ratios of the transformer 71 are changed so that the output of the transformer corresponding to variation of a power source 1 is nearly constant. |
