An indirect method of measuring DC bus capacitor current

This paper describes a general method to measure inverter DC bus capacitor current in an indirect manner. The method measures input and output voltage and current and calculates DC bus capacitor current. The method applies to standard inverters and common bus inverters. Commonly available test equipment will be used. The investigation will develop the theory that describes the indirect method. It will also discuss test equipment selection and set up, and data analysis. Practical implementation issues are also discussed. A comparison between direct (in-situ) and indirect measurements will be made