分布式电源即插即用临界条件在配电线路中的分布规律及快速估算

Distribution Law and Rapid Estimation of Distributed Generation Plug-and-play Critical Conditions in Distribution Lines

分布式电源(distributed generation,DG)等即插即用要素接入配电网已成为未来智能电网发展的趋势,为保证其能顺利接入,提出DG即插即用临界条件的概念。综合考虑负荷与DG功率变化、电压、线路容量、潮流倒送及DG功率因数等约束,提出一种计算DG即插即用临界条件的数学模型。通过理论分析,将临界条件模型中的约束条件进行等效化简,推导出DG即插即用临界条件与接入点到母线电气距离的函数关系。在此基础上,提出不同应用场景下DG即插即用临界条件的快速估算方法。以负荷递减分布的23节点算例和修改的IEEE33节点算例为例,针对不同应用场景,分别采用估算方法与数学优化算法进行计算,结果表明所提的估算方法是可行的,在误差允许的范围内能够实现对DG即插即用临界条件的快速估算。

The plug-and-play access to the distribution network,such as distributed generation,has become the trend of smart grid development in the future.In order to ensure its smooth access,the concept of DG plug-and-play critical conditions is proposed.Considering the constraints of load and DG power changes,voltage,line capacity,power flow reversal and DG power factor,a mathematical model for calculating the plug and play critical condition of DG is proposed.Through theoretical analysis,the constraint conditions in the critical condition model are equivalently simplified,and the functional relationship between the DG plug-and-play critical condition and the electrical distance from the access point to the bus bar is derived.On this basis,a fast estimation method for DG plug-and-play critical conditions in different application scenarios is proposed.Taking the 23-node of the load-decreasing distribution and the modified IEEE-33 node as an example,the estimation method and the mathematical optimization algorithm are used for different application scenarios respectively.The results show that the proposed estimation method is feasible,and the rapid estimation of the DG plug-and-play critical conditions can be realized within the error tolerance.