Operating principle of Soft Open Points for electrical distribution network operation
Operating principle of Soft Open Points for electrical distribution network operation
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DOI：
10.1016/j.apenergy.2015.12.005
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发表时间：
2016-02
期刊：
影响因子：
11.2
通讯作者：
Wanyu Cao;Jianzhong Wu;N. Jenkins;Chengshan Wang;T. Green
中科院分区：
文献类型：
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作者：
Wanyu Cao;Jianzhong Wu;N. Jenkins;Chengshan Wang;T. Green
软开关点(SOP)是在配电网中安装的代替常开点的电力电子装置。它们能够在正常网络运行条件下提供有源潮流控制、无功补偿和电压调节，以及在异常情况下提供快速故障隔离和供电恢复。为SOP的运行开发了两种控制模式，使用背靠背电压型变流器(VSC)。潮流控制方式采用电流控制，实现有功功率和无功功率的独立控制。带有电压控制器的电源恢复模式可为因网络故障而隔离的负载供电。研究了基于背靠背VSCS的SOP在正常和非正常网络运行条件下的工作原理。对一个双馈线中压配电网的研究表明，SOP在正常、故障期间和故障后恢复供电的不同网络运行条件下的性能。在网络运行条件发生变化时，采用基于锁相环控制器的模式切换方法实现两种控制模式之间的转换。通过直接模式切换的硬转变被注意到是不利的，但通过采用软冷负载拾取和电压同步过程获得了无缝转变。
Soft Open Points (SOPs) are power electronic devices installed in place of normally-open points in electrical power distribution networks. They are able to provide active power flow control, reactive power compensation and voltage regulation under normal network operating conditions, as well as fast fault isolation and supply restoration under abnormal conditions. Two control modes were developed for the operation of an SOP, using back-to-back voltage-source converters (VSCs). A power flow control mode with current control provides independent control of real and reactive power. A supply restoration mode with a voltage controller enables power supply to isolated loads due to network faults. The operating principle of the back-to-back VSCs based SOP was investigated under both normal and abnormal network operating conditions. Studies on a two-feeder medium-voltage distribution network showed the performance of the SOP under different network-operating conditions: normal, during a fault and post-fault supply restoration. During the change of network operating conditions, a mode switch method based on the phase locked loop controller was used to achieve the transitions between the two control modes. Hard transitions by a direct mode switching were noticed unfavourable, but seamless transitions were obtained by deploying a soft cold load pickup and voltage synchronization process.