特高压直流分层接入交流电网方式下直流控制系统设计  

Control System Design for UHVDC Hierarchical Connection to AC Grid

作　　者：李少华[1] 王秀丽[1] 张望 胡永昌 

机构地区：[1]西安交通大学,陕西省西安市710049 [2]许继电气股份有限公司,河南省许昌市461000

出　　处：《中国电机工程学报》2015年第10期2409-2416,共8页Proceedings of the CSEE

摘　　要：多馈入直流集中落点负荷中心将是我国未来电网发展面临的重大问题,在电网结构方面特高压直流分层接入交流电网方式是亟待研究的课题,该方式下的直流控制系统缺乏深入研究。文中首先对特高压直流分层接入方式下的直流控制系统整体结构进行了详细分析,发现在所提的分层接入方式下,整流站直流控制系统与普通特高压直流的控制系统区别不大,但逆变站存在较大差异。分层接入的逆变站与两交流系统相联系,直流电流、电压及熄弧角控制器应该配置在阀组层,并建议在串联双阀组的中间配置直流电压测点。其次,通过对受端系统的等效分析,证明了两交流系统的无功耦合程度较弱,无功功率可以独立平衡,交流滤波器需分开配置。由于高、低端串联阀组分别接入不同的交流电网,换流变分接头也需独立控制。最后应用PSCAD/EMTDC仿真验证了整个直流控制系统的合理性和有效性。The multi-infeed high voltage direct current （HVDC） transmission system in load center will be the prominent problem in the development of China power grids, ultra high voltage direct current （UHVDC） hierarchical connection to AC grid from the aspect of grid structure needs further study urgently. There was no in-depth study on the control system for UHVDC under this mode. The paper mainly studied the control system for UHVDC hierarchical connection mode. The control system for rectifier station is similar to the conventional UHVDC system due to its similar main circuit structure, while there are some differences in the inverter station. Firstly, the DC current controller, DC voltage controller and extinction angle controller should be configured in valve group level, while a DC voltage measuring point between the series valve groups is suggested. Secondly, the coupling characteristic between the two AC systems was analyzed. Because of the weak coupling, the reactive power of AC systems should be controlled independently, and so are the AC filters arrangement and control. The transformer tap changer for high and low valve group should also be controlled independently as they are connected to different AC system. Finally, a case of UHVDC transmission using PSCAD/ EMTDC validated the whole DC control system.

关 键 词：分层接入方式 特高压直流 控制系统 无功功率控制 交流滤波器控制 换流变分接头控制 

分 类 号：TM72[电气工程—电力系统及自动化]