Design Of Automation System And Protection Unit For Marine Power Station

The "Belt and Road" construction has strengthened trade between China and countries along the route.Meanwhile,the increase in external trade has also driven the development of the modern shipbuilding market.The development of modern ships tends to be large,and the equipment is becoming intelligent.Moreover,the types and quantities of marine electrical equipment are increasing,which poses new problems for the production,distribution and consumption of marine energy.Therefore,it is necessary to carry out automatic control of marine power station to manage loads and ensure the continuity of power supply.At the same time,the high reliability and security are required.The protection unit of the system is essential,which is conducive to the normal operation of the marine electrical equipment and improves the work efficiency.The main functions and principles of the marine power station and the protection unit are introduced.Based on the experimental platform of marine power station in Dalian Maritime University,the overall hardware design of the marine power station automation is proposed,and the specific details are also described.The design of the collecting circuit is presented and the electrical parameters such as voltage,current are collected by taking Digital Signal Processor(DSP).Then,the acquired data are sent to the Programmable Logic Controller(PLC)through the RS485 bus as the basis for logic judgment.The PLC is used as the core controller.By internally and automatically conducting contrastive analysis,marine power station automation functions are realized,such as the startup and closed-down of generator-sets,synchronization control,automatic load distribution,heavy load inquiry,and staged unloading of secondary loads,etc.Concurrently,a protection unit is also set for the generators,which mainly includes overload,short circuit,under voltage and reverse power protection to ensure the safety of electricity consumption.The marine power station monitoring system is completed and the configuration interface is displayed.The WEINVIEW MT8100i touch screen displays power parameters,fault alarms,and controls the operating status of the marine power station,providing useful information to workers.Finally,it is verified on the experimental platform.After obtaining the field data,the least square method is employed to fit the speed regulation characteristics of the marine power station.The oscilloscope is applied to show the current changes before and after the parallel operation,and the phase detection error is analyzed.At the same time,the rapidity and stability of the load transfer process are verified,so that the automation process is optimized.The experimental results show that the system can be continuously and stably operated on the platform,which proves the feasibility of the design.