The Analysis Of Chaos Parameter In Wind Power System And Its Control Method

With the rapid development of wind energy conversion technology, wind energy, the clearand renewable resource，is widely used for generating electric power in the world. It benefitshumans a lot and also attracts scholars’ attention. During the last30years, people served toimprove its quality, as the large scale wind farms are connected to the grid, problems occurred,including the voltage collapse, bifurcation and chaos phenomenon, etc. This brings risk to thesystem stability character. This paper intends to discuss the factors lead to chaotic behaviors.Based on the simulation result, the sliding mode control method is used to suppress chaoticoscillation. The work and conclusions are as follows:1、Take chaos research of power system into consideration, we analyzed two situations,first, set reactive power as parameters, whenQ1increased to a certain value, we observedchaos phenomenon, later, maximum LE and the correlation dimension were calculated toconfirm that chaos did occur in the system. Keep increasing theQ1, the system is likely to beinstable. Meanwhile, set the periodic active disturbance and periodic reactive disturbance tothe system, it presented that both the amplitude and frequency influence chaotic behavior, asthe amplitude value increased, there is a chaos parameter zone, only the disturbance valueexceeded this range, can chaos occurred. As to varying the frequency, the system is likely todirectly be instable.2、Based on the studies in Chapter3, a static var compensator(SVC) is added to thechaotic wind power system, the simulation result in Matlab showed that the oscillation waned.However, the SVC failed to eliminate chaos thoroughly, in order to set the system operate atthe arranged state, we used sliding mode control method to control chaos. As this strategy isadaptive to variable parameter system, it was available in wind power system. While the delayin time and space would cause chattering, we adopted quasi-sliding mode control to solve thisproblem, based on exponent trending law, the chattering phenomenon was eliminated, and thesystem dynamic character had been improved.