AC VOLTAGE CONVERTING CIRCUIT AND CHANGE DETECTING CIRCUIT FOR AC VOLTAGE AND ACTIVE POWER DETECTING CIRCUIT AND REACTIVE POWER DETECTING CIRCUIT

摘要

PROBLEM TO BE SOLVED: To provide a compact and light AC voltage converting circuit, change detecting circuit for AC voltage, valid power detecting circuit, and invalid power detecting circuit capable of obtaining a desired voltage with satisfactory linearity without causing any phase deviation.;SOLUTION: This circuit is provided with a voltage dividing circuit 2 in which a plurality of resistors 7 and 8 whose resistance values are different are serially connected, and an AC voltage is supplied to the voltage dividing circuit 2 so that the AC voltage generated between the both edges of the desired resistor, for example, the resistor 8 can be amplified by an isolated amplifier 3 as a converted voltage. As for the isolated amplifier 3, one input circuit 9 is constituted of an electronic circuit floating from a ground potential, and another output circuit 10 is constituted of an electronic circuit whose one edge is grounded.;COPYRIGHT: (C)2002,JPO