Research Of Control System For Double-fed Wind Turbine

Wind energy power, as a new type green energy,,is being a new technology field which the states all over the worlds want to develop.with the developments of industry,shortage of electricity and the problem of power supply,using reproducible energy—wind energy which will be the most important clean substitute enetgy is of great significance for abating the shortage of energy。Meanwhile technique of variable speed constant frequenccy used on double-fed machine become the mainstream of wind energy power by its low cost and high efficiency.At first,the article analysed the theory of variable speed constant frequenccy , introduced the working principle,mathematical model and vector control theory of double-fed wind power system, analysed the function needs of control system.,then,we designed the structure of double-fed wind power control system ,including convertor-cell,paddle-change cell,crab-cell,temperature-cell .after that,we designed the system structure based on PLC.This paper analysed the control errand and the control flow of the sub-control section of the power system,and also list its control parameters,and configure the control system's hardware using the programmable logic controller of SIMENS S7200,including the choose of CPU,digital module,analog module,temperature module and communication module.The maximum power extraction is a important research content of wind turbine. To meet up deficiency of traditional power feedback signal control and hill-climbing control, a control method based on fuzzy control for Maximum output power point(MPPT) is presented which regulates the rotor speed of generator using fuzzy algorithm on the basis of the mutative direction of the rotor speed increase. As a result, the extraction of maximum power is improved.at the base of hardware established this paper finished the ladder diagram using the STEP 7 MicroWIN V4.0,including main program,maximum power extraction program,crab program,temperature detecting program and communication program.At last, graphical user interface is designed and developed using configuration software WINCC of SIMENS, which can establish friendly Human—Machine interface.