Electrical wiring in substation includes primary circuit wiring and secondary circuit wiring.
The primary circuit, also known as the main circuit, refers to the circuit through which the electric energy flows. The main equipment includes generators, transformers, circuit breakers, isolation switches, lightning arresters, fuses and voltage and current transformers, etc. The wiring of the main circuit is to connect these devices with wires as required.
The function of the secondary circuit is to control, protect, measure and monitor the primary circuit. The main equipment includes control switches, buttons, relays, measuring instruments, signal lights and automatic devices.
Main line connection mode commonly used in power transformation and distribution:
Busbar free main line: line-transformer component line, bridge connection, polygon connection
Single bus main connection: single bus without section connection, single bus section connection, single bus section with bypass bus connection
Double bus main wiring: double bus without section wiring, double bus section wiring, two thirds of the breaker double bus wiring, double bus section with bypass bus wiring