Abstract <p>The problem of determining a faulty element of a capacitor bank in the composition of a higher harmonic filter of a static thyristor compensator is considered. The existing methods of searching for a damaged capacitor based on the analysis of current and voltage imbalance have been analyzed. The possibility of using the unbalance current analysis method in the search for a faulty capacitor for static stationary compensators installed in power supply systems of arc furnaces of high and ultrahigh power is shown. For a broadband second harmonic filter, an analysis of the resistor current is proposed in order to further reduce the search area for a damaged capacitor. The study was conducted using a simulation model in the MATLAB Simulink package. A significant reduction in the search time for a faulty capacitor battery element in the filters is shown. The proposed method is implemented in production conditions using the capabilities of the existing automatic control system for the static thyristor compensator MACH2.</p>