Title |
Reference Model Updating of Considering Disturbance Characteristics for Fault Diagnosis of Large-scale DC Bus Capacitors |
DOI |
https://doi.org/10.5370/KIEEP.2017.66.4.213 |
Keywords |
DC-link of power converter ; Electrolytic capacitor ; ESR(equivalent serises resistance) ; Fault diagnosis ; Initial ESRo |
Abstract |
The DC electrolytic capacitor for DC-link of power converter is widely used in various power electronic circuits and system application. Its functions include, DC Bus voltage stabilization, conduction of ripple current due to switching events, voltage smoothing, etc. Unfortunately, DC electrolytic capacitors are some of the weakest components in power electronics converters. Many papers have proposed different algorithms or diagnosis method to determinate the ESR and tan {\delta} capacitance C for fault alarm system of the electrolytic capacitor. However, both ESR vary with frequency and temperature. Accurate knowledge of both parameters at the capacitors operating conditions is essential to achieve the best reference data of fault alarm. According to parameter analysis, the capacitance increases with temperature and the initial ESR decreases. Higher frequencies make the reference ESR with the initial ESRo value to decrease. Analysis results show that the proposed DC Bus electrolytic capacitor reference ESR model setting technique can be applied to advanced reference signal of capacitor diagnosis systems successfully. |