变桨风力发电机组控制器优化设计

Optimization Design of Controller for Pitch Wind Turbine

风速的随机性和风电机组控制系统的非线性导致难以获取风电机组精确的数学模型。鉴于实际的风电工程通常采用简单的比例-积分-微分(proportional integral differential,PID)控制器或比例-积分(proportional integral,PI)控制器达到输出恒定功率的控制目标,不涉及复杂的智能控制算法,在风速高于额定风速时,提出了一种基于加性分解原理的方法来规范风力发电机组变桨控制器的设计参数,将风力发电机组变桨控制问题分解为2个简单的子问题,即线性时不变主系统的追踪问题和辅系统的镇定问题。基于该原理,设计出了简单的PI控制器,并在此基础上进行了控制器优化设计,而且通过理论推导给出了该控制器的稳定性证明,最后通过仿真验证优化后的控制器能够大大增加输出功率的平稳性。这将为今后设计风力发电机组变桨控制器设计提供一定的准则。

Due to the randomness of wind speed and the nonlinearity of control system for wind power generating units it is hard to achieve accurate mathematical model of wind power generating units. Since the simple proportional integral differential （PID） controller or proportional integral （PI） controller are generally applied in actual wind power generation projects to achieve the control objective to output constant power and it does not come down to complex intelligent control algorithm, in the occasion that the wind speed is higher than rated wind speed an additive decomposition based method is proposed to normalize the design parameter of variable pitch controller for wind power generating units, that is, the variable pitch control problem of wind power generating unit is decomposed into two simple subproblems, namely the tracing of linear time-invariant main system and the stabilization of auxiliary system. Based on the proposed principle, a simple PI controller is designed, and the optimization design of the controller is carried out, and then the stability of this controller is proved by theoretical derivation. Finally, the fact that using the optimized controller the stationary of the output power can be greatly enhanced is validated by simulation results.