Hot standby control circuit of BBU module, storage system and server

The invention discloses a hot standby control circuit of a BBU module, a storage system and a server, and relates to the field of standby power, the connection relation among a PSU module, the BBU module, a voltage reduction module and a load is controlled through a first control module and a second control module: when the PSU module works normally, the PSU module supplies power to the load through the second control module, and when the PSU module works normally, the BBU module supplies power to the load through the second control module; meanwhile, power is supplied to the voltage reduction module through the first control module, the electric quantity of the BBU module does not need to be consumed, the charging frequency of the BBU module is reduced, and the service life of the BBU module is prolonged; the BBU module and the step-down module are in a normally open state, and when a fault occurs in the PSU module or between the PSU module and the load, the first control module controls the BBU module to be