闭环运行方式城市配电网接线模式的研究

摘要

In the open-loop distribution network, the reliability can not be increased and the DG can not be connected better. However, in the closed-loop distribution network, the faulty line section can be isolated automatically, the normal line section can be recovered rapidly, and it needs not outage in non-fault zone. So, the civil line and industrial line which form a closed-loop system can improve the utilization rate of equipment and the voltage qualification rate by loads complementary. The maximum short-circuit current value of faulty line is similar between the closed-loop system and the open-loop system, but short-circuit current flows through more lines. The paper proposes the centralized protection to solve the protection problems in the closed-loop operation system. The new distribution network planning principle of using typical connection mode and planning according to the partition, section, load density and load characteristics is given.%配电网的开环运行影响了供电可靠性的进一步提高和分布式电源的友好接入。通过分析发现：采用闭环运行方式的配电网，在故障隔离、定位和恢复供电的过程中，非故障区域不需要停电；可以将民用线路和工业线路组成一个环网，形成用户负荷特性互补，从而提高设备利用率和电压合格率；闭环运行不会导致线路最大短路电流出现明显的变化，但会导致短路电流流经更多的线路。讨论了在闭环运行模式下，采用集中式保护来解决环网运行方式的保护配置问题，提出了采用按分区、分段、负荷密度和负荷特性的方式进行规划，并尽量采用典型接线模式的新型配电网规划原则。