考虑风电调频能量联动分配的时变调频参数设定方法

Parameter Setting Method of Time-varing Frequency Regulation Considering Linked Energy Distribution of Wind Power for Frequency Regulation

功率扰动发生的随机性使得风电调频能量具有不确定性,导致其设定的调频参数可能无法匹配实际调频能力,并具有一定不可知性;同时,虚拟惯量和一次调频具有相同的调频能量来源,无法实现合理的自然分配,使得电网无法获知体现风场调频能力的等效参数。为此,从电网运行的角度,构建了风电调频能量联动分配机制,使得虚拟惯量和一次调频在总量约束下联动分配两个调频环节的能量;在此基础上,考虑运行点偏移的机械能捕获损失,根据风速信息得到风机可释放净能量的表达模型;进一步,根据能量分配模型计算等效调频参数,由此使得风电在中低风速下可参与快速调频全程,避免电网调频环节间的能量失衡,并具备与时变风速和实际调频能力相匹配的明确等效调频参数。最后,阐明了所提方法在风场端和电网端的应用模式。仿真算例结果表明,等效风电调频参数可通过获取变化风速数值滚动更新,具有联动、可知的特性,且跟随风速变化具有时变性,可以有效反馈风电实际的调频能力,使得电网运行可及时获取风场及全网的调频水平。

The randomness of power disturbance leads to the uncertainty of the frequency regulation energy of wind power,resulting in that the setting parameters of frequency regulation may not match the actual frequency regulation capability and may be unknowable.At the same time,the virtual inertia and the primary frequency regulation have the same energy source of frequency regulation,which cannot achieve a reasonable natural distribution,making the power grid unable to obtain equivalent parameters that reflect the frequency regulation capability of the wind farm.Therefore,from the perspective of grid operation,a linked distribution mechanism of frequency regulation energy of wind power is constructed,so that the virtual inertia and primary frequency regulation are linked up to distribute the energy of the two frequency regulation links under the total constraint.On this basis,considering the capture loss of the mechanical energy of the operation point offset,an expression model of the net energy that can be released by the wind turbine is obtained according to the wind speed information.Furthermore,the equivalent frequency regulation parameters are calculated according to the energy distribution model,so that the wind power can participate in the entire process of rapid frequency regulation at low and medium wind speeds,which avoids energy imbalances between grid frequency regulation links,and has clear equivalent frequency regulation parameters that match the time-varying wind speed and actual frequency regulation capabilities.Finally,the application modes of the proposed method on the wind farm side and the power grid side are clarified.The simulation results show that the equivalent frequency regulation parameters of the wind power can be updated by obtaining the value of changing wind speeds,which has the characteristics of linkage and knowability,and is timevarying following the changing wind speeds,and can effectively feedback the actual frequency regulation capability of wind power,so that frequency regulation capability levels of the wind farm and the whole network are timely obtained for the grid operation.