Building intercom system and control method

The invention relates to the field of intercom systems, in particular to a building intercom system and a control method. According to the invention, by setting the first SOC and dividing the working mode of the battery into the first mode and the second mode according to the actual SOC of the battery, charging protection of the battery can be realized, efficient and stable work of the battery is protected, and the specified power and the first voltage are set in the first mode according to customer requirements. Tracking and locking of maximum voltage corresponding to specified power and meeting customer requirements are realized by changing step length, and furthermore, by constructing a voltage-current double-closed-loop control circuit based on constant voltage output, voltage feed-forward and current feed-forward, it is ensured that voltage with extremely high stability can still be output under the condition of multiple power supplies, and the stability of the power supply is improved. Therefore, the ef