| 摘要 |
There has been a need for smaller-scale power factor measurement devices able to measure the power factor with a single element. This power factor measurement device is characterized by comprising: a pair of connecting ends (12) for connecting to a power source in parallel with a load; two magnetic elements (21, 22) by which identical external magnetic fields cause different changes in electric resistance; a pair of measurement terminals (13) for outputting a differential voltage of the two magnetic elements; a power factor sensor unit (10) comprising a pair of sensor terminals (10t) connected to the pair of connecting ends (12); a voltage detection unit (15) for measuring the voltage between the measurement terminals (13); a low-pass filter (16) connected to the output of the voltage detection unit (15); a high-pass filter (17) connected to the output of the voltage detection unit (15); a rectifier (18) connected to the high-pass filter (17); and a dividing means (19) for dividing the output of the low-pass filter (16) and the output of the rectifier (18). |
