考虑电网结构和参数的电力系统惯量分布特性

随着电力系统中新能源大规模接入,系统惯性时间常数下降以及惯量分布不均的特性突显.对此,文中利用节点计算惯量这一指标表征节点阻碍频率变化的能力,进而考虑电网结构和参数分析系统的惯量分布特性.然后,分别对两机系统和多机系统节点计算惯量进行了理论推导,获得了节点计算惯量的解析表达式,并在两机系统、8机36节点系统中对节点计算惯量进行了验证和分析,同时对节点计算惯量进行了灵敏度分析以研究区域间惯量的相互影响.分析结果表明:通过系统参数获取节点计算惯量能够定量表征系统惯量分布特性.

Inertia Distribution Characteristics of Power System Considering Structure and Parameters of Power Grid

With the increasing penetration of renewable energy in power system, the characteristics of the decreasing time constant for the system inertia and the uneven distribution of the inertia are prominent. To this end, the index of calculated node inertia is used to characterize the ability of nodes to resist frequency changes, and then the grid structure and inertia distribution characteristics of parameter analysis system are considered. Then, the calculated node inertia of the two-machine system and the multi-machine system is theoretically deduced, and the analytical expression for calculated node inertia is obtained. The calculated node inertia is verified and analyzed in a two-machine system and an 8-machine 36-node system. At the same time, a sensitivity analysis of the calculated node inertia is carried out to study the mutual influence of the inertia between regions. The analysis results show that the calculated node inertia obtained by system parameters can quantitatively characterize the distribution characteristics of the system inertia.