A Partial Discharge Survey was carried out on all 33kV substations at High Penn Solar Farm, with IPEC’s PrecisePD, CC-TEV and AA sensors. Particular attention was paid to the RMUs and transformers.
Tests showed that 7 of the 8 substations tested were free of PD. However, one substation, had high PD in the region of the cable terminations at the base of the RMU.
IPEC recommended to the customer that the PD source be further investigated by conducting a visual inspection made for any signs of discharge activity on the surface of the insulators and, if possible, energised whilst exposed to allow ultrasonic pin pointing of the source to be conducted.
Either PD monitoring or a scheduled program of testing every 3, 6 or 12 months is recommended to assess for PD in the future and maintain good asset condition.