New device for the quality control of the high-voltage electrical insulator

Abstract

During the operation of high-voltage electrical equipment, its insulation ages, its properties deteriorate, and the electrical strength decreases. To avoid sudden breakdowns of insulation and maintain the necessary level of reliability of high-voltage electrical equipment, the state of its insulation must be periodically monitored. The device described in the article is intended for preventive testing and diagnostics of heterogeneous high-voltage insulation of electric machines, power oil transformers and cables with paper-oil insulation. In particular, the integral assessment of high-voltage insulation aging, its humidification and remaining operational life can be based on the use of the absorption phenomenon (the accumulation of internal absorbed charge). Self-discharge and return voltage are measured to assess the insulation condition. A block diagram of the device for monitoring the electrical insulator quality is given as well as the formulae for determining the spent and remaining operational life of the tested insulation. The proposed device will increase the operational reliability of high-voltage electrical equipment.