A feasibility and method research on the on-line monitoring of parallel compensation capacitors

As important reactive power equipment, parallel compensation capacitors play a key role in improving the power quality and the structure of the power system. At present, the detection of parallel compensation capacitors generally takes offline test, and the fault in operation mainly relies on the protection device action to be removed. However, there is a scarcity of online detection methods. According to the industry standard specification, the capacitor will be a failure when the capacitance changes over a certain value. And the current flowing through the capacitor will reflect the capacitance change. Based on the current monitoring, the running status of the capacitor could be diagnosed. The paper analyzes the feasibility of this method, and designs a system for the on-line monitoring of the parallel compensation capacitor capacitance, combined with highpotential power supply and wireless acquisition and transmission technology. Finally, the laboratory tests verify the feasibility of the method.