A Model-Based Monitoring Method for Offline Accelerated Testing of DC-Link Capacitor in Three-Phase Inverter Systems

摘要

This letter proposes a model-based monitoring method for the dc-link capacitors in three-phase inverter systems without the need for extra high-performance hardware and intensive computation. By injecting an ac voltage into the dc link and applying the appropriate theoretical analysis, a mathematical model of C can be developed. As the proposed method only requires estimating the parameters from the input voltage and current, there is no need to modify the hardware and control scheme inside the inverter, and the amount of data to be monitored and processed is reduced. Thus, the proposed method is easy to implement for accelerated tests of commercial inverters. Additionally, simulations and experiments are carried out to verify the analysis and effectiveness of the proposed solution.