CAPACITOR'S REMAINING LIFETIME DIAGNOSING DEVICE, AND ELECTRIC POWER COMPENSATING DEVICE HAVING THE REMAINING LIFETIME DIAGNOSING DEVICE

摘要

In an instantaneous voltage drop compensating device, when an instantaneous drop occurs, an electric power transformer (8) performs an inverter action so that the electric power of a side-by-side placed capacitor (7) is DC/AC-converted and fed to a load (3). At this time, a capacitor's remaining lifetime diagnosing unit (100) introduces the DC voltage value, the DC current value, and the temperature value of the side-by-side placed capacitor (7) thereinto, and uses a prestored program for computing a remaining lifetime, thereby diagnosing the remaining lifetime, for which the side-by-side placed capacitor (7) can be used under the state where a capacitor discharge time period exceeds a rated compensation time period. As a result, the remaining lifetime, for which the side-by-side placed capacitor (7) can be used, can be diagnosed under the situations where the discharge time period for the side-by-side placed capacitor (7) to discharge while outputting the rated electric power exceeds the rated compensation time period required as the time period for which an electric power compensating device has to output the rated electric power.