风电叶片疲劳加载激振系统解耦控制算法及试验研究

风电叶片逐渐向大型化方向发展，为了提高大型风电叶片疲劳试验的激振能力、缩短测试周期，两激振源联振已成为疲劳测试方法中具有前景的发展方向。首先进行两激振源的耦合特性试验，设计了激振源转速、相位和叶片振幅的测试方案。当2个激振源初始转速设定为35 r/min时，风电叶片在该激振源作用下进行试验，得出2个激振源转速差在±5 r/min范围内波动、相位也存在耦合现象，叶片振幅变化絮乱。为了提高两激振源的同步效果，在分析现有控制策略的基础上，采用并联交叉耦合结构，开发了滑模变结构同步控制算法，并利用李雅普诺夫函数证明了该算法的渐近稳定性。最后，搭建了一套10 MW级大型风电叶片疲劳试验平台，开发了基于分布式网络总线的疲劳激振控制系统，将该滑膜变结构控制算法应用于aeroblade 2.0~54.38风电叶片两点激振试验。试验结果表明，在两激振源转速均为35 r/min时，两激振源的转动步调一致，相位也能基本保持同步，此时叶片振幅最大，且非常稳定。在不同的初始速度驱动下，分别设定为40和30 r/min，2个激振源的转速均能快速跟随并分别保持。由于两者转速不一致，导致叶片振幅发生波动。上述试验结果表明，虽然2个激振源之间的机电耦合是固有存在的，但是设计的滑模变结构控制算法能使2个激振源的转速、相位步调一致，具有良好的鲁棒特性，有效地保证了疲劳试验的顺利进行。

Decoupling Control Algorithm and Experimental Study of Wind Turbine Blade Fatigue Loading Excitation System

The wind turbine blade is gradually developing towards large scale.In order to improve the excitation ability of wind turbine blade fatigue test and shorten the test cycle,the coupling vibration of two exciters has become a promising development direction in fatigue test methods.First of all,the coupling characteristic test of two exciters was carried out,the blade test plan of excitation source speed,phase and amplitude was designed.The wind turbine blade was tested under the effect of this excitation source,in which the two exciters initial speed were set to 35 r/min.The results showed that two excitation speed difference was in the range of ±5 r/min,phase existed coupling phenomenon and the blade amplitude was disorderly.In order to improve the synchronization effect of two exciters,based on the analysis of the existing control strategy,using parallel cross coupled structure,the sliding mode variable structure control algorithm was developed by using the Lyapunov function and the asymptotic stability of the algorithm was proved.Finally,a set of 10 MW large test platform of wind turbine blade fatigue was built,the fatigue excitation control system based on distributed network bus was developed,and the sliding mode variable structure control algorithm was applied to aeroblade 2.0~54.38 wind turbine blade fatigue test,in which test was driven by two exciters.Test results showed that in both the excitation source speed were 35 r/min,the rotational two exciters phase keep step,phase can also basic synchronized,and the blade amplitude was the largest and very stably.Under the different initial speed drive,respectively set as 40 and 30 r/min,the speed of the two exciters can quickly follow and keep respectively.Due to the inconsistency of the two rotational speeds,the amplitude of the blade was fluctuating.The test results showed that although the electromechanical coupling between two exciters was sequestration,the development of the sliding mode variable structure control algorithm could make two exciters keep step with rotational speed,phase,and had a good robust property,effectively guarantee the smooth progress of fatigue test.