The Design And Realization Of Alternative Marine Power Supply Control System And Protection Unit

Along with our economic development,the scale of shipping trade has continued to expand.Usually,during ship berthed in the port,it is powered by diesel generators,which will meet its daily demand,but it has caused the serious air pollution to the port area.In order to build green ports,countries all over the world are seeking solutions.In recent years,alternative marine power has become the main mean to solve the port air pollution,and the alternative marine power control system is a kind of application of shore power technology.The alternative marine power supply system is composed of three parts,such as shore power supply system,cable connection system and ship receiving power system.On the basis of the classification and composition of each part,this paper introduces the function and principle of each part and also describes the technology of ship-to-shore switching and the protection unit in the electrical system of the ship.Based on the research of ship shore electrical connection system,this paper puts forward the overall design scheme of alternative marine power supply control system.Take TMS320 F28335 DSP as the power parameter acquisition module to complete the sampling of voltage and current,and calculate the power parameters such as voltage,current,frequency and power based on the software phase-locked loop method.Taking S7-1200PLC as the core controller,it receives the power parameters transmitted by the DSP in Modbus protocol.The controller comprehensively analyzes,judges and controls the operating state of the system to realize the automation function of the ship shore connection.It includes automatic parallel operation of marine generator and shore power supply,automatic transfer of load,automatic cutting and stopping of marine generator and removal of shore power supply.The safety interlock circuit is designed for the alternative marine power supply control system to realize the safety chain and emergency cut-off function.Based on the analysis of possible faults of shore power supply and marine generator,reverse power,overload,under voltage,short circuit and power transfer limit protection are designed to ensure the safe connection of shore power.For the Altermative Marine Power Supply Control System,an integrated monitoring system was designed,which is mainly composed of the ship shore power connection system diagram and the ship generator state monitoring diagram,etc.and the WEINVIEW touch screen was selected as the monitoring carrier.A verification experiment was carried out on the marine automation high-voltage power station platform of Dalian Maritime University for the uninterrupted switch technology and automatic load transfer of ship-to-shore.Finally,an experiment is designed to verify the reliability of the integrated protection unit.