含有大量感性负荷的海岛微电网黑启动优化策略

在极端自然条件下,容易造成海岛微电网全面崩溃,此时需要进行黑启动使整个系统恢复,但是海岛微电网中含有大量感性负荷会影响黑启动过程.为了提升海岛微电网黑启动的效率,提出一种基于虚拟有功负荷的海岛微电网黑启动优化策略.首先提出黑启动电源启动顺序优化模型,利用熵权法对不同DG的黑启动能力进行评价;然后,提出负荷恢复优化模型,以负荷恢复量最大和负荷恢复重要程度最大作为目标并利用PSO算法进行求解;接着,提出DG与负荷的路径恢复优化模型并利用最小生成树的Prim算法进行求解.另外,还提出虚拟有功负荷构造方法,在黑启动过程中考虑将感性负荷与并联补偿电容一起等效为有功负荷,从而提高黑启动成功率.最后,采用简化的19节点微电网结构进行仿真验证,结果表明,与传统优化的黑启动策略相比,本文方法在黑启动过程中负荷恢复量提高了46.8％,同时考虑了负荷的重要程度,并且,路径恢复总时间减少了8.8％.此外,根据本文中提出的虚拟有功负荷构造方法,仿真结果表明当并联电容提供的无功足够时,在黑启动过程中可以明显减小感性负荷对系统电压造成的影响.

Black start optimization strategy for island microgrid with large number of inductive load

Extreme natural conditions often cause the collapse of the island microgrid which needs to be restored by the black start. However, the black start is affected by a large number of inductive load due to the particularity of the island microgrid load. In order to improve the efficiency of the black start of island microgrid, this paper proposed a black start optimization strategy of island microgrid based on virtual active load. First, a black start power startup sequence optimization model was proposed and the entropy weight method was used to evaluate the black start ability of different DGs. Then, a load recovery optimization model was proposed with the maximum load recovery amount and the maximum load recovery importance as the goals and solved by the PSO algorithm. Next, the path recovery optimization model of DG and load was proposed. The model was solved by Prim algorithm of minimum spanning tree. In addition, a virtual active load construction method was proposed. In the black start process, the inductive load and the parallel compensation capacitor are considered equivalent to the active load, thereby improving the black start success rate. Finally, the simplified 19-node microgrid structure was used as the test system for simulation verification. The simulation results show that, compared with the traditional optimization of black start strategy, the proposed method increased the load recovery by 46.8% during the black start process and at the same time, took the load importance into consideration. Furthermore, the total path restoration time was reduced by 8.8%. In addition, according to the proposed virtual active load construction method, the simulation results show that when the reactive power provided by the parallel capacitor was sufficient, the impact of the inductive load on the system voltage could be significantly reduced during the black start process.