A Real Time Predictive Maintenance System of Aluminium Electrolytic Capacitors Used in Uninterrupted Power Supplies

This paper presents a low cost method to realize a real time condition monitoring and a predictive maintenance system of an electrolytic capacitor used in uninterrupted power supplies (UPS). This method consists in detecting the changes on real time in equivalent series resistance (ESR) and the capacitance C values of the electrolytic capacitors. Simulation and experimental results are presented to illustrate the proposed monitoring technique. The proposed method can be used in UPS where waveforms are continuously varying in amplitude, frequency and versus temperature. The proposed on line failure prediction method has the merits of using only the existent resources in UPS and with the use of knower algorithms.