What are the requirements for dual protection of intelligent substation?

The relay protection with voltage level of 220kV and above and its related equipment and network shall be configured according to the principle of duality, and the relay protection with duality configuration shall meet the following requirements: (1) Each complete and independent protection device shall be able to handle all possible faults. There should be no electrical connection between two sets of protection. When one set of protection is abnormal or exits, it should not affect the operation of the other set of protection. (2) The voltage (current) sampling values of two sets of protection shall be taken from independent merging units respectively. (3) The merging unit with dual configuration should be in one-to-one correspondence with two independent secondary sampling systems of electronic transformer. (4) GOOSE (SV) networks used for dual configuration protection should follow the principle of mutual independence. When one network is abnormal or exits, it should not affect the operation of the other network. (5) Two sets of protection trip circuits should correspond to two intelligent terminals respectively; The two intelligent terminals should correspond to the two tripping coils of the circuit breaker respectively. (6) Two sets of single-pot communication equipment (including multiplexed optical fiber channel, independent fiber core, microwave, carrier and other channels and processing equipment) shall be equipped for double-line longitudinal protection. ), and two sets of communication equipment should use independent power supply. (7) Two sets of 7)DC-powered dual protection and related equipment (electronic transformer, merging unit, intelligent terminal, network equipment, tripping coil, etc.). ) should be one-to-one. (8) The protection of dual configuration should adopt the main and rear integrated protection devices.