Research And Design Of Megawatt Doubly-fed Wind Turbine Control System

Environment and energy are two important problems which human faced to solve.It has great significance to use renewable,green energy for solving these problems.The use of wind power has drawn high attention for its various outstanding advantages,and has become a new energy technology research hotspot all over the world.This paper presents the development and technology status of wind power in China and other countries,introduces the most widely applied wind turbine types.It describes the advantages of wind turbines with variable speed and constant frequency.This paper analyzes the construction and principle of the megawatt wind turbine with variable speed and pitch,interprets the functions of all composing parts,and suggests the control theory of double-fed wind turbine.The control system of a 2MW doubly-fed wind turbine is researched and designed in this paper.The system contains three main functions:Main control system,Pitch system,and yaw system.The turbine will get the perfect control and the advanced technology by Main control system which used PLC.The main control system and the slave systems are connected with CAN bus,which ensures the actual time and integrity of the transmission of data and control signals.The hardware structure and composition of the control system are mainly introduced.The design of PLC system and HMI system,yaw system,lighting protection system,speed and wind speed measurement system are also designed in this paper.The main concepts of software control logic of the control system is designed based on hardware system.The main functions of turbine control are detailed analyzed,contains status switch,stop turbine,alarm,interlock,heating,ventilation and so on.The program of PLC is realized,and HMI is also developed.The entire control system is compact,maintainable and extensible.The response is rapidly,the control is precise,the HMI is friendly,the logical is reasonable.The system running in a good condition and it is stable and reliable.The operation is simple and convenient.The users will get a very considerable economic benefits by the advantage of this control system.