A Research On Optimization For Energy Saving Of The Induction Generator In Wind Power Generation System

Nowadays, the problem of energy shortage is increasingly serious, andtherefore, utilization and exploitation of renewable energy is an urgenttask required by social and economic sustainable development.Countriesall over the world value the exploitation of wind power as animportant renewable and alternative energy source. In wind powergeneration system, the wind turbine usually works in low wind speed andthe converter works in the light-load condition. For the full powerconverter of the induction generator of the wind power generation system,if the traditional constant flux control strategy is used in the generatorside converter, the generator will take on low efficiency because of highloss. From this point of view, it is certain to bring benefits for wind powersystem to reach its goal of energy saving if we focus on the research ofoptimization for energy saving of induction generator in wind powergeneration system.Aiming at the full power converter of the squirrel cage inductiongenerator (SCIG), this paper first brings iron loss resistance which isvarying with the speed of generator into the system, and then a model of vector controlled induction generator considering the value-varying ironloss resistance is built. On this basis, it discusses the method of gettingthe best rotor flux set value, and uses this value to rotor flux orientationvector control system to realize the accurate control for inductiongenerator. Secondly, this paper does the research of the loss modelcontrol for the flux optimization design. By this control strategy, weobtain the best rotor flux set value corresponding to optimal operatingconditions of least loss through the real-time signal collection of speedand torque of induction generator. In practical application, we can make atable containing variables of speed, torque and flux in optimal operatingconditions so as to get the best flux set value fast by looking up the table.Thirdly, this paper studies the application of search algorithmbased onfuzzy control theory in the induction generation energy-savingoptimization control. This method does not need the accurate informationof generation model, and can realize the reasonable value set on thesystem level including converter, generator, filter and line. At last, acomprehensive energy-saving solution combining the advantages of twomethods mentionedabove is proposed for the full power converter of theSCIG. Based on the proposed method, we build up the Matlab/Simulinksimulation platform and experimental platform of350kW inductiongenerator converter respectively to realize the validation. The simulationand experimental results prove that the proposed method has a better energy-saving effect, andillustrate that the method presentedcan offeranew way to make the SCIG converter operate efficiently.