| 摘要 |
<p>PURPOSE: To improve insulation between a transmitting part and monitor provided in a GIS(gas insulated switchgear). CONSTITUTION: In a transmitting part 13, a means 14 and an R8, by which a constant current Ia is made to flow into a light emitting element LED, means 15 and an Rt, by which an oscillated pulse current Ib with the second frequency depending on temperature is mad to flow, and means 16 and 17, by which an oscillated pulse current Ic with the first frequency depending on gas pressure, are provided. The optical signal of the light emitting element LED is guided into the light receiving means of a detecting part through an optical fiber 3. The detecting part receives the optical signal, breaks down the signal into the DC component and the AC component, computes the ratio of the AC component and the DC component in the first period, detects the gas pressure, computes the ratio of the AC component and the DC component in the second period and detects the temperature. By obtaining the ratios, the errors caused by the transmission loss of the optical fiber can b cancelled. Since the GIS and the monitor are insulated by the optical fiber, the special insulating structure is not required.</p> |
