| 摘要 |
<p>PURPOSE:To detect voltage and a current with high accuracy even with respect to a wide range of a temp. change, by providing the thermometric means provided in close contact with the inner surface of a housing and a temp. compensation circuit for compensating the temp. characteristic of a light applied electromagnetic sensor. CONSTITUTION:The voltage of a charge part 1 is divided by voltage dividers 2, 3 to be applied to a light applied voltage sensor 4. The light sent to the sensor 4 from a signal processing part 6 through an optical fiber 5 is modulated in luminous intensity corresponding to the voltage applied to the sensor 4 to be again sent to the processing part 6 through the fiber 5 to be converted to the quantity of electricity proportional to the voltage of the charge part 1. A temp. compensation circuit 10 compensates the temp. of the sensor 4 arranged in the vicinity of the charge part 1 from the circumferential temp. data detected by a thermometric means 9 composed of a thermistor and the temp. rise value data of the charge part 1 calculated from the value of the current flowing to the charge part 1 detected by a current detection means 8 constituted of a current transformer or a photoelectric converter. By this method, the voltage of the charge part 1 can be measured with high accuracy.</p> |
