风电叶片双惯性激振疲劳加载耦合振动特性

Coupling Characteristics of Dual Inertial Exciter Blade Fatigue Loading System

摘要:

针对风电叶片电驱动双惯性激振疲劳加载时出现耦合问题，通过对加载系统进行合理简化，基于拉格朗日方法建立疲劳加载过程中的动力学数学模型，并由此构建系统的机电耦合方程.利用小参数周期平均法对耦合过程近似解析，并推导了系统振动同步稳定的条件，得出系统运行过程中电动机负载转矩的影响因素，揭示系统出现耦合现象的机理，对系统频率特性进行数值仿真，得到不同加载频率下叶片振动特性.通过实际叶片疲劳试验验证数学模型、理论推导及仿真结果的正确性，为风电叶片疲劳加载系统同步控制策略制定提供理论依据及工程应用参考.

关键词:风电叶片; 疲劳试验; 惯性激振器; 耦合振动

Abstract:

A mathematical equation system was derived based on the Lagrange method for wind vane electric double inertia vibrator fatigue loading system, and thus a electromechanical coupling equation of the system was built. Using the small parameter cycle average method, the approximate analytic system vibration was derived for coupling process synchronization stability conditions. The influencing factors on the motor load torque in the process of system operation were obtained, and the mechanism of system coupling was revealed. On this basis, a simulation model was established to numerically simulate system frequency characteristic, and the vibration characteristics of blade under different loading frequencies were obtained. Experimental study on system frequency characteristics, main resonance electromechanical coupling characteristics, and control synchronization verifies the correctness of the mathematical model and simulation model and the feasibility of the control, providing reference for engineering application of fatigue loading system and test.

Key words:wind blade; fatigue testing; dual inertial exciter; coupling vibration