Bidirectional DC-DC control method for hybrid power ship

The invention provides a bidirectional DC-DC control method for a hybrid power ship. According to the method, charge and discharge states of a marine lithium battery and charge and discharge current can be controlled by a bidirectional DC-DC converter, and energy distribution of the hybrid power ship can be more reasonable. The control method includes four mods and one state and includes automatic control, manual control and state transition. A control strategy includes that: when the operating modes are switched, a controller transmits a power request command to the bidirectional DC-DC converter so that the bidirectional DC-DC converter adjusts the output power in real time; when a hybrid power system operates, the output voltage of the bidirectional DC-DC converter is limited by direct-current bus voltage. The bidirectional DC-DC converter is provided with an RS485 interface and an analog and switching output interface, and the bidirectional DC-DC converter switches the operating modes under control of a PLC (programmable logic controller).