Substation distribution equipment is all the switching equipment, auxiliary equipment connected to a current carrying conductor

Substation transformer is center equipment, transformer using the principle of electromagnetic induction. Substation distribution equipment is all the electrical switches, mcb circuit breaker conductor auxiliary equipment connected devices. Its role is to receive and distribute electricity. Distribution equipment mainly by bus, high voltage circuit breaker switch, choke coils, transformers, power  air circuit breaker , surge arresters, high voltage fuse, secondary equipment and other ancillary equipment necessary for the composition.
Secondary equipment refers to a system state measurement, control, monitoring and protection equipment installations. These devices are constituted by a circuit called the secondary circuit, general secondary system.