基于最大电功率跟踪的风力发电系统幂指数趋近滑模控制

Sliding mode control using power-exponent approach rate for wind power generation system based on maximum electric power tracking

文章考虑机组转轴摩擦损耗和发电机本体的电损耗,从减小发电功率损耗、提高整机风电转换效率出发,设计了一种基于MPPT原理下的最大电功率点跟踪(MEPT)控制策略,该策略在考虑转轴摩擦损耗和发电机绕组损耗基础上,推导出发电机最大电功率跟踪输出控制模型方程。采用转矩跟踪型MPPT控制策略,利用动态滑模控制原理,设计了基于幂指数趋近律的风电系统MEPT滑模功率控制器。控制律引入输入变量的积分,在时间上形成滑模控制的动态连续性,抑制了MEPT功率跟踪的抖振,增强了控制精度、平滑性与鲁棒性。通过静、动态多种风况的Matlab仿真实验,验证了MEPT控制的正确性。

Considering the friction loss of the rotating shaft and the electrical loss of the generator itself, in order to reduce the power loss and improve the efficiency of wind power conversion of the whole generator, a maximum electric power point tracking(MEPT) control strategy based on MPPT principle is designed, which takes into account the friction loss of the rotating shaft and the loss of the generator winding. On the basis of this, the maximum power tracking output control model equation of the generator is derived. A power exponential approach law based MEPT sliding mode power controller for wind power system is designed by using the torque tracking MPPT control strategy and the dynamic sliding mode control principle. By introducing the integral of input variables into the control law, the dynamic continuity of sliding mode control is formed in time, the chattering of power tracking of MEPT is suppressed, and the control accuracy,smoothness and robustness are enhanced. The correctness of MEPT control is verified by MATLAB simulation experiments under static and dynamic wind conditions.