| Human demand for energy continues to increase with the global population growth,but many energy sources cannot be regenerated in a short time.Moreover,the global greenhouse effect caused by excessive consumption of fossil fuels has made humans urgently looking for new green renewable energy sources.In this context,wind energy has received increasing attention as a new type of green renewable energy.This article takes the variable speed variable pitch wind turbine as the research object.Firstly,based on the detailed analysis of the system function structure and control strategy of the variable speed variable pitch wind turbine,the control scheme design of the main control system of the unit is determined,including the torque control system,the pitch control system and the load optimization system.At the same time,the GH Bladed simulation software is used to simulate and analyze the optimal torque controller designed in this article.Secondly,the area is divided into three areas:Cp constant area,constant rotating speed area,and power constant area.The control strategies and processes of the three operating areas are designed in detail.In the Cp constant area and the constant rotating speed area,according to the control target and the variable pitch wind turbine characteristics,a suitable torque controller is designed to ensure the maximum power point tracking capability of the unit.In the power constant area,the pitch controller is added to the torque controller based on the control target and the variable pitch wind turbine characteristics.Since the unit drive train has a low damping characteristic,the effect of suppressing the unit load is achieved by superimposing the ripple on the output of the torque controller.According to the empirical data,the PI controller parameters are set,and the controller parameters are continuously simulated by GH Bladed software to design the optimal torque controller of the variable speed variable pitch wind turbine.Finally,taking a 1.5MW wind turbine as a model,the optimal torque control method is compared with the traditional control method.Through the recording and analysis of the system simulation experiment data under different wind conditions,it is concluded that the unit has better dynamic performance and can reduce part of the mechanical load under the control of the optimal torque controller.The optimal torque controller control strategy has engineering application conditions. |
