Method for guaranteeing current-equalizing charging of charging machines when charging machines are connected in parallel

The invention discloses a method for guaranteeing current-equalizing charging of charging machines when the charging machines are connected in parallel. At least two charging machines connected in parallel in a master and slave mode are included, data are transmitted between a master machine and slave machines through (CAN) communication, and in the early stage of charging, the master machine and the slave machines work in a constant-current charging mode; when the master machine and the slave machines are converted from the constant-current charging mode into a constant-voltage charging mode, the master machine detects output charging current of the master machine and the slave machines in real time, meanwhile, the master machine calculates total real-time charging current in real time, when the total real-time charging current is smaller than preset charging current by a certain set value, the master machine controls and adjusts each charging machine through (CAN) communication, and the master machine and the slave machines can share the total real-time charging current in average. The method has the advantage that the phenomenon that one certain charging machine is too large in load and accordingly the single machine or all the machines break down is avoided.