CAJ | 학술논문

大容量光伏集中并网必定会对整个配电网特别是并网点的电压造成一定的影响,而光伏出力的随机性也会引起电压的随机波动.为此,建立了光伏集中并网后引起并网点电压偏差的数学模型,导出了以电压偏差不越限为约束的光伏准入容量,定义了能够全面反映母线电压波动情况的4项指标,即分布重心、离散度、偏度和峰度,提出一种评估光伏并网下电力系统电压波动状况的方法.基于光伏出力的随机模型在PSCAD中建立了符合实际情况的光伏电站组件,并以单电源链式配电网为例验证了上述指标的准确性和有效性.最后将所提指标和方法用于某地区含光伏电站电网的电压波动程度的评估,结果表明该指标和方法可为光伏电站并网点的优选提供参考依据.
대용량광복집중병망필정회대정개배전망특별시병망점적전압조성일정적영향,이광복출력적수궤성야회인기전압적수궤파동.위차,건립료광복집중병망후인기병망점전압편차적수학모형,도출료이전압편차불월한위약속적광복준입용량,정의료능구전면반영모선전압파동정황적4항지표,즉분포중심、리산도、편도화봉도,제출일충평고광복병망하전력계통전압파동상황적방법.기우광복출력적수궤모형재PSCAD중건립료부합실제정황적광복전참조건,병이단전원련식배전망위례험증료상술지표적준학성화유효성.최후장소제지표화방법용우모지구함광복전참전망적전압파동정도적평고,결과표명해지표화방법가위광복전참병망점적우선제공삼고의거.
Centralized grid connection of large capacity photovoltaic power undoubtedly causes certain influence on voltage in distribution network, especially at point of common coupling (PCC), and random fluctuation of photovoltaic power output leads random voltage fluctuant in power grid. Therefore, a mathematical model of PCC's voltage deviation under centralized grid connection of large capacity photovoltaic power is constructed and PV penetration capacity under voltage constraint is derived. Four indexes are defined to fully reflect bus voltage fluctuation, namely distribution center, discrete degree, skewness and kurtosis and accordingly a method assessing voltage fluctuation of power system is put forward. Based on stochastic model of photovoltaic output, photovoltaic power station module in accordance with actual situation is established in PSCAD. A single power supplied chain distribution network is taken as an example to verify the accuracy and validity of these proposed indexes with PSCAD simulation. Finally, the proposed indexes and method are applied to evaluate the voltage fluctuation of a regional power grid with photovoltaic power station. The results show that the evaluation indexes and corresponding method can provide instructive reference for PCC selection.