Method for determining equivalent series resistance of direct current link circuit capacitor in inverter of motor vehicle, involves determining equivalent series resistance, based on ratio of determined voltage jump and determined current

摘要

The method involves switching on a load (105) in parallel to a direct current (DC) link capacitor (135). The load is switched off after a predetermined waiting period. A voltage jump is determined at the DC link capacitor, when the load is switched off. A current that flows just before the switching off is determined by the load. An equivalent series resistance is determined, based on a ratio of the determined voltage jump and the determined current. A regression is determined, based on the sample values that lie above a predetermined threshold. Independent claims are included for the following: (1) a computer program product with a program code to carry out method; and (2) an inverter for operating a load of a direct current power source.