张北柔性直流电网交流耗能装置运行特性仿真

为验证利用可控硅将大功率电阻快速投入交流系统的耗能装置能否在投运后安全可靠运行,从而解决张北柔直工程双极性接线故障状况下过负荷造成的线路和设备损毁问题,该工作通过PSCAD电磁暂态仿真软件建立了张北换流站交流耗能装置的电路模型;然后对耗能装置的运行特性进行了分析,并模拟了过剩风能与耗能装置分组投切时系统的电压电流;最后讨论了耗能装置故障状况对系统的影响。结果表明:耗能装置可以快速有效地消纳过剩功率,且当其故障时不会对系统造成威胁。可见交流耗能装置设计合理,可将其投运在柔性直流系统中。

Simulation of Operation Characteristics of AC Energy Dissipation Device in Zhangbei Flexible DC Grid

In order to verify whether the energy-consuming devices that use thyristors to quickly put high-power resistors into the AC system can operate safely and reliably after being put into operation,so as to solve the problem of line and equipment damage caused by overload in the bipolar wiring fault condition of Zhangbei flexible DC project,the circuit model of the AC energy dissipation device of Zhangbei Converter Station was established by PSCAD electromagnetic transient simulation software.Then the operating characteristics of the energy dissipation device are analyzed,and the voltage and current of the system when the excess wind energy and the energy dissipation device are switched into groups are simulated;finally,the influence of the energy dissipation device fault condition on the system is discussed.The results show that the energy-consuming device can quickly and efficiently dissipate the surplus power,and will not pose a threat to the system when it fails.It is concluded that the AC energy dissipation device has a reasonable design and can be put into operation in a flexible DC system.