Method and Apparatus for Determining Maintenance of DC Busbar Filtering Electrolytic Capacitor

A device for determining maintenance of a DC busbar filtering electrolytic capacitor, the device comprising:

• a data recording module to record a DC busbar voltage of the DC busbar filtering electrolytic capacitor in a driving circuit of a driving motor during charging of the DC busbar filtering electrolytic capacitor wherein the DC busbar voltage is a difference between voltages at two ends of the DC busbar filtering electrolytic capacitor;
• a first determination module to determine a charging starting time point and a charging ending time point according to the recorded DC busbar voltages, and selecting a time point from time points between the charging starting time point and the charging ending time point;
• a parameter calculation module to calculate a time constant according to a starting voltage corresponding to the charging starting time point, an ending voltage corresponding to the charging ending time point, the selected time point and the DC busbar voltage corresponding to the selected time point;
• and
• a second determination module to determine whether it is necessary to perform maintenance for the DC busbar filtering electrolytic capacitor, according to the time constant.