The implementation of a cost-efficient damped AC testing methodology for transmission cables based on DC–AC conversion and distributed partial discharge detection

Abstract

This research introduces a novel damped alternating current (DAC) testing methodology, which integrates an enhanced DAC generator with a pulse-based distributed partial discharge (PD) detection technique. The advanced DAC generator is designed without the need for high voltage (HV) solid-state switches, thereby offering a cost-effective solution for field-testing voltage generation through a direct current–alternating current conversion approach. To meet the demand for high instantaneous power, a capacitor bank is employed as the power supply. Furthermore, the implementation of a distributed PD detection technique enhances sensitivity and eliminates limitations associated with cable length. To minimize the construction costs of the distributed PD-detection system, a pulse synchronization technique has been employed. Efforts to reduce the system's weight were informed by simulations, resulting in the design and development of a prototype weighing 850 kg for a 64/110 kV power cable. The reduction in the number of HV solid-state switches contributes to significant cost savings, amounting to tens of thousands of dollars, when compared to conventional DAC generators. Laboratory and field tests validated the effectiveness of the cost-efficient DAC testing methodology.