Abstract Over the past few years, there has been a rise in the quantity of underground cables used in power transmission and distribution networks in many urban areas worldwide. Technological and economic considerations, along with space constraints, are responsible for this increase. As the number of cables increases, utilities face challenges in effectively maintaining and testing their condition. Particularly, the maintenance of medium-voltage cables, such as three-core 33 kV cables, is becoming increasingly challenging. One of the biggest problems with medium-voltage cables is their preference when the load is closer to the substation. Because the cables are closer to the source, the probability of the end termination kit failing is higher, leading to short-line faults (SLF). Short-line faults subject the connected switchgear and transformers to severe electrical, thermal, and mechanical stresses. Cable faults can cause equipment failure, resulting in external flashovers, which in turn raise the temperature and ultimately lead to insulator failure. Low external temperatures can increase moisture content in the environment, leading to equipment failure. This paper investigates switchgear failures in 132/33 KV substations caused by cable faults and ambient temperature and presents methods to mitigate switchgear and instrument transformer failures caused by cable faults. Over time, the proposed methods have led to a decrease in the number of failures. In recent years, protocols such as IEC61850, MODBUS, IEC60870-4, and others have transformed conventional substations into automated substations. We propose a low-cost, practically feasible solution using the GOOSE technique in the IEC61850 protocol to prevent the flashover of the circuit breakers, following a detailed investigation.
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