Capacitor capacitance diagnostic device and capacitor power diagnostic device equipped electrical power supply device

摘要

A capacitor capacity diagnosis device (1) has the following: a power supply (3), which is used to charge a capacitor (2), a discharge circuit (4), which is connected in parallel to the capacitor (2), in order to supply energy to the capacitor (2) discharged, a resistance divider circuit (5), which is used to measure a voltage drop value during the discharge, a measuring circuit (6), which measures the divided voltage, and a diagnostic circuit (7), which determines the adequacy of the capacitor capacitance on the basis of a voltage change over time due to the discharge , This enables the adequacy of the capacitor capacity of an electrical power supply device to be diagnosed during operation.