描述交直流并列系统电网结构品质的3种宏观指标

Three Macroscopic Indexes for Describing the Quality of AC/DC Hybrid Power Grid Structures

合理的电网结构是保证电力系统安全稳定运行的最重要的物质基础,但是目前还没有具体的指标可以对电网结构的品质进行定量评估。归纳和提出了3种描述交直流并列系统电网结构品质的宏观指标,分别为通道强度指标、电压强度指标和频率强度指标。通道强度指标包括交直流通道强度比指标和交流通道抗冲击强度指标,分别用于描述交直流通道的强直弱交程度和交流通道抵御直流通道潮流转移冲击的能力;采用多馈入有效短路比作为电压强度指标,用于评估电网对直流换流站的电压支撑能力;采用频率偏差因子作为频率强度指标以衡量电网的频率支撑能力。综合3种指标可以描述交直流并列系统电网结构的某些重要品质,从而实现对交直流并列系统的电网结构品质的定量评估。

A reasonable power grid structure is the most important material foundation to guarantee the stability and security of a power system.However,there is no specific quantitative index for describing the quality of the power grid structure yet.This paper summarized and proposed three macroscopic indexes to evaluate the quality of the AC/DC hybrid power grid structures,which were the corridor strength index,the voltage support strength index and the frequency support strength index respectively.The corridor strength index included the ratio of the AC corridor strength to the DC corridor strength and the strength of the AC corridor to resist the DC corridor power flow shift shock,which could describe the relative strength of the AC and DC corridors and the strength of the AC corridor to resist the shock of the DC corridor power flow shift.The multi-infeed effective short circuit ratio was used as the voltage support strength index to evaluate the voltage support ability for the DC converter stations.The frequency bias factor was adopted as the frequency support strength index to measure the frequency support ability of the power grids.The three macroscopic indexes can reflect some important quality of the AC/DC hybrid power grid structures and provide an effective tool for quantitative assessments of the AC/DC hybrid power grid structures.