HVDC恒功率与准稳态模型在低频振荡分析中的比较  

Comparison Between Constant PQ Model and Quasi-steady-state Model of HVDC in Low Frequency Oscillation Analysis

作　　者：杨帆[1] 陈陈[1] 金小明[2] 吴小辰[2] 王西田[1] 史慧杰[1] 沈梁[1] 

机构地区：[1]上海交通大学电气工程系,上海市200240 [2]中国南方电网技术研究中心,广东省广州市510620

出　　处：《电力系统自动化》2008年第6期9-13,19,共6页Automation of Electric Power Systems

基　　金：国家自然科学基金重大项目(50595410);国家科技支撑计划资助项目(2006BAA02A17)~~

摘　　要：对大规模交直流输电系统进行低频振荡(LFO)分析时,直流系统通常采用恒定功率模型或准稳态模型来表示,对这2种不同的直流模型,需要考虑采用简化的恒定功率模型会对计算结果带来何种程度的影响。文中采用基于增广系统状态方程的模态分析法,研究了直流准稳态模型与恒定功率模型之间的差别,并对这2种模型用于LFO计算的结果进行了分析和比较。理论分析和仿真结果表明,直流定功率运行时,两端换流母线处注入或吸取的有功功率基本保持恒定,而换流站消耗的无功功率变化。对于区间振荡模态,恒定功率模型得到的稳定性结论较准稳态模型偏保守。对于大规模交直流输电系统,直流系统采用恒定功率模型来简化表示可以接受。Constant PQ model or quasi-steady-state （QSS） model are widely used for HVDC links in the large-scale AC/DC power system low frequency oscillation （LFO） analysis. An important concern of the two types of HVDC models is that to what extent the calculation results are impacted by using the constant PQ model. The differences between the two models are investigated by a modal analysis method based on the augmented system state equation （ASSE）. The calculation results using the two models are compared in a LFo analysis. The theoretical and simulation results indicate that, when the HVDC system operates under the constant power control, the active power that the converters inject into or withdraw from the AC system is approximately constant, while the reactive power drawn from the AC system is varied. For the interarea mode, the results from the constant PQ model are more conservative than that of the QSS model. For a large-scale AC/DC power system, it is acceptable to represent the HVDC links by the constant PQ model.

关 键 词：交直流系统 低频振荡 恒定功率模型 准稳态模型 

分 类 号：TM721.1[电气工程—电力系统及自动化] TM712