Insulation evaluation of capacitive equipment by power loss density

The paper presents a new approach to assess the insulation condition of capacitive equipment based on power loss density. Power loss angle is an important parameter to evaluate the insulation condition of capacitive equipment, but it cannot represent the actual power loss of the equipment without considering its capacitance and volume. In the paper, through listing some engineering cases and theoretical analysis, the power loss of the capacitive equipment is calculated under different applied voltage and converted to the corresponding power loss density per unit volume which normalize the operation voltage, capacitance and volume of the equipment. By analyzing the power loss density, insulation evaluation of different kinds of capacitive equipment is identified. Based on the power loss density, qualitative diagnosis and assessment for the capacitive equipment have been presented, which will be supportive for condition assessment and diagnosis of capacitive equipment.