大基地风电场“以大代小”等容量排布方案分析

Study on Equal Capacity Arrangement Scheme for Large Base Wind Farms during Replacing Small Wind Turbines with Large Ones

“以大代小”是风电项目进行等容或扩容改造升级常用的一种方式。以大基地风电场为研究对象,探究针对大基地项目进行“以大代小”技术改造的规划方案。将大基地风电场划分为9个待改造区域,分别采用两种改造方案,从机组单机容量、机组轮毂高度、改造区域机组对周边机组的尾流影响等几个关键因素入手,分析这些因素对场区发电量的影响及发电量提升效果,进而得到最优的改造机型和布局规划。研究结果表明,保持轮毂高度不变,提升单机容量,发电量增加幅度并不显著。当抬升轮毂高度且提升机组单机容量时,发电量提升效果较为明显。当选取的轮毂高度与周边机组轮毂高度较为接近时,随着改造区域单机容量增大,对周边机组的尾流影响越大,影响最大的为处于改造区域下风向的机组,影响最小的通常为处于改造区域上风向的机组。抬升轮毂高度,随着单机容量的提升,发电量提升效果较为显著。根据大基地风电场的实际风资源条件,在场区中间区域适当抬升轮毂高度,可以提升发电量并减少对周边风电场的尾流影响。等容量技术改造时,应优先选择高塔架大兆瓦机组进行改造。

"Replacing small wind turbines with large ones"is a common way for the equal capacity replacement or capacity expansion of wind power projects.Taking large base wind farm as the research object,this paper explores the planning scheme of"replacing small wind turbines with large ones"for the technical transformation of large base projects.The large base wind farm is divided into 9 areas for transformation,and two transformation schemes are adopted respectively.The influence of several key factors,such as single unit capacity,hub height and the wake effect of wind turbines in transformation area on surrounding wind turbines,on the power generation in wind farm area and the power generation improvement effect are analyzed,thus obtaining the optimal transformation model and layout planning.The results show that the increase in power generation is not significant when the hub height remains unchanged and the single unit capacity increases.When the hub height is raised and the single unit capacity is increased,the power generation is increased obviously.When the selected hub height is close to that of the surrounding wind turbines,the wake effect on the surrounding wind turbines increases with the increase of single unit capacity in the transformation area.The wind turbines downwind of the transformation area are the most affected,while the wind turbines upwind of the transformation area are the least affected.With a raised hub height,the power generation increases significantly with the increase in single unit capacity.According to the actual wind resource conditions of large base wind farms,properly raising the hub height in the middle area of wind farm can increase the power generation and reduce the wake effect on surrounding wind farms.During equal capacity replacement,high tower large megawatt wind turbines should be selected in priority.