限功率运行下风电场的发电量计算研究

STUDY ON CALCULATION OF POWER GENERATION CAPACITY OF WIND FARM UNDER LIMITED POWER OPERATION

近年来,在风电机组招标后风电场的总装机规模难以做到与批复时的装机规模一致,为满足批复文件的输出功率限制要求,风电场在实际运行过程中需考虑风电机组的限功率运行。而风电项目前期设计过程中并未详细考虑其后续实际的限功率运行状况,若以等效满负荷小时数同比例估算限功率运行后的风电机组年发电量,得到的结果往往偏小。通过对比限功率运行时各种风电场年发电量计算方法的优缺点,提出一种全局迭代寻优策略。结果显示:1)采用年等效满负荷小时数折算法得到的限功率运行时风电场年发电量会明显低估风电场理论年发电量,当项目收益在盈亏平衡点附近时应避免采用该方法。2) Meteodyn WT软件建立的模型质量决定了全局迭代寻优策略结论的准确性,在使用该方法时需要通过多塔交叉检验、同塔切变检验等多种方式对模型进行验证。使用该方法得出的限功率运行策略易于实施,且能最大化提高风电场总体效益。

In recent years,it has been difflcult for the total installed capacity of wind farms to be consistent with the approved installed capacity after bidding for wind turbines.In order to meet the output power limit requirements of the approval documents,wind farms need to consider the power limiting operation of wind turbines in the actual operation process.In the early design process of wind power projects,the actual power limiting operation status was not carefully considered.If the annual power generation capacity of wind turbine after power limiting operation is estimated based on the same proportion of equivalent full load hours,the results obtained are often too small.This paper proposes a global iterative optimization strategy by comparing the advantages and disadvantages of various calculation methods for the annual power generation capacity of wind farms during limited power operation.The results show that using the annual equivalent full load hours conversion algorithm to obtain the annual power generation capacity of wind farms during power limiting operation will signiflcantly underestimate the theoretical annual power generation capacity of wind farms.This method should be avoided when the project income is near the breakeven point.The quality of the model established by Meteodyn WT software determines the accuracy of the conclusion of the global iterative optimization strategy.When using this method,the model needs to be validated through multiple methods such as multi tower cross validation and same tower shear testing.The power limiting operation strategy obtained using this method is easy to implement and can maximize the overall beneflts of the wind farm.