| 摘要 |
A power measuring apparatus should be compact, and capable of measuring, in a single element, the categories of active power, reactive power, power factor and apparent power. The present invention has: a pair of connecting ends for connection to a power supply in parallel with a load; a sensor element having a pair of sensor terminals disposed on both ends of a magnetic film portion, one end of the sensor terminal being connected to one of the connecting ends, the sensor element being arranged adjacent to a connecting wire such that the longitudinal direction of the magnetic film portion is substantially parallel to the direction of flow of electric current in the connecting wire; n band pass filters connected in parallel to another end of the sensor terminals of the sensor element; a phase regulator connected in series to each of the band pass filters; a selection switch for selectively connecting the phase regulator; a measurement resistor having one end connected to the selection switch and the other end connected to the other connecting end; and a voltage detection unit, the measurement terminals of which being the respective sensor terminals, the voltage detection unit measuring the voltage between those measured terminals. |
