| 摘要 |
PURPOSE:To realize a detection for a fault of a sensor circuit, by performing a check calculation by giving a sampling to various types of analog inputs with every fixed time and comparing the result of calcuation and the decision data file. CONSTITUTION:For the electric power system comprising the power source 1, the electric power transformer 9-1 and 9-2 plus the loads 2-1-2-4, the current quantity of the main circuit is transformed by the current transformers 3-1-3-3. At the same time, the voltage quantity of the main circuit is transformed by the gauge transformers 4-1-4-3. The current and the voltage thus transformed are converted into the DC voltage value for the effective electric power quantity, the phase angle, the reactive electric power quantity, the current quantity, the voltage quantity or the like through the converters 8-1-8-12 of an analog sensor circuit to be supplied to the electronic computer 6A. The computer 6A samples the input analog quantity with every fixed time to carry out the prescribed check calculations relating to each other. This result of calculation is compared with the prescribed decision data file with a consideration taken into the error or the like to decide whether the input value is normal or not. In such way, a fault can be detected for a sensor circuit without using any DC-DC converter. |
