Research On The Matching And Designing Mathod Of Composite Structrue Wind Generator System

As coal, oil and other resource are increasingly drying up, developing renewableenergy for our society is more and more important.Because wind power generationsystem causes no pollution and its technology is relatively mature, it has a goodprospect. The common two wind power generation system are doubly-fed wind powersystem and direct-drive wind power system. Although doubly-fed system has a goodmarket, the multistage gearbox in the system and the brushes and slip ring of thegenerator require a lot maintenance, making the system not reliable. For direct drivesystem, no gearbox saves the system the relevant maintenance and using permanentmagnet electric machine makes the system more efficient. But due to connecting tothe wind turbine, the generator is huge and assembling and transportation isdifficult.Besides the system adopts full power converter which increases the cost.This thesis proposes a composite wind generator system, and the system consists ofa adjustable speed motor, a generator and a planetary gear. It eliminates full powerconverter in direct drive system. Single-stage planetary gear adopted in the systemimproves the generator speed, thus reducing the volume of the generator. Comparedwith doubly-fed system single-stage planetary gear makes reliability of the systemimproved.This article first studies the matching method of the system.By analyzing theoutput characteristic of wind turbine and then treating it as the input of the system, theexpression of the power flow in the system is obtained. According to the expression,key parameters that affect system are analyzed. Basing on the applicaion of the system,A reasonable matching method is put forward. Under the reasonable matching, the twomachines performance indexes are studied.Then a12kW prototype is analyzed and designed. Firstly the structure design iscarried and parameters of the prototype are determined. Then according to theparameters the generator and adjustable speed motor are designed. Finite elementsimulation is carried and the planetary is designed. According to the final plan, aprototype is manufactured.Main parameters of two electric machines are tested by experiments. Experimentplatform is built including the composite structure wind generator. Experiments ofgrid connection and power generation after connection are done, verifying the feasibilityof the function and the correctness of the system matching method.