网源协调驱动下考虑网络转供能力的配电系统多目标双层近期规划

Multi-objective bi-level short-term planning of distribution system considering network transfer capability under network-generation coordination drive

提高供电能力和对分布式电源(DG)的接纳是未来环网状配电网扩展规划的新目标。为此,通过引入安全距离这一配电网N-1安全评价指标,提出了一种考虑N-1安全和DG与网架协调的配电网多目标双层优化规划模型。该模型以改造线路、新增负荷接入位置和DG安装位置及容量为决策变量,计及了系统故障负荷的转供和不可控DG出力及负荷波动带来的不确定性。根据模型的特点,利用多场景技术将随机性问题转化为确定性问题,并采用正态边界交点和动态小生境差分进化算法组成的混合策略对模型加以求解。通过算例对比分析了是否考虑N-1安全和网源协调对规划结果的影响,仿真结果表明,所提规划模型能够在提高DG渗透率的同时,挖掘配电网的供电潜力和推迟线路改造;所得规划方案实现了配电网经济效益和安全水平的综合优化,更适用于负荷增长平缓和占地通道资源紧张的城市建成区配电网近期扩展规划。

Improving the power supply capability and accommodation of DG （Distributed Generation） are the new objectives of expansion planning of future loop distribution network. Therefore, a multi-objective bi-level optimization planning model for distribution network is proposed, which considers the N-1 security and coordination between net- work and DG by introducing the safety assessment index of safe distance. The model takes the reformed feeders, new load locations and installation locations and capacities of DG as decision variables, and considers the transfer of sys- tem failure load and uncertainties caused by uncontrollable DG output and load fluctuations. According to the cha- racteristics of the model, the stochastic problem is transformed into deterministic problems by multi-scenario tech- nology, and then is solved by the hybrid strategy combining normal boundary intersection and dynamic niche diffe- rential evolution algorithm. The planning results considering N-1 security and coordination between network and DG or not are compared by case analysis. Simulative results show that, the proposed planning model can improve the DG penetration level, exploit the potential power supply capability of distribution network and postpone the upgrade of lines simultaneously, and the planning scheme realizes the comprehensive optimization of economic benefit and safety of distribution network, which is more applicable to short-term expansion planning of urban developed distribution network with slow load growth and scarce line corridors.