互联系统长期动态仿真的结构保留建模

Modeling of Long-term Dynamics for Interconnected Power Systems with Structure-preserved Network

为了研究互联电力系统在级联事件下的频率和电压长期动态特性及其控制,提出了一种网络结构保留的多区域互联系统长期动态仿真模型和算法。与动态潮流计算相似,模型假定系统已渡过初始的暂态稳定阶段且有足够阻尼,从而忽略同一控制区域的机组间相对摇摆,即假定每个控制区域具有统一的频率动态,即区域内惯量中心动态,以便仿真几分钟及更长时间的长期动态。IEEE30节点3区域系统的仿真结果表明了文中建议的仿真模型的可行性和计算方法的有效性;与详细机电暂态仿真软件仿真结果的比较表明,"区域统一频率动态"假定引起的系统长期动态仿真误差在工程上可以接受。从而为进一步开展级联事件下的频率和电压长期动态的稳定控制和协调提供了仿真工具。

In order to study the long-term frequency and voltage dynamics of interconnected power systems under cascading events, this paper suggests an appropriate mathematical model and its simulation algorithm with the network structure preserved. Similar to traditional dynamic power flow, the proposed model assumes that the system has survived the transient stability and has sufficient damping torque. Therefore, the relative swings among generator rotors in one area will be neglected in long-term dynamics; and each control area is recommended to have a uniform frequency, represented by its area center of inertia （COI）, with a simulation of the long^term frequency and voltage dynamics and the investigation on its effective control strategies. Computer test results of the IEEE 3-area 30-bus system show the validity and effectiveness of the proposed model and algorithm. The proposed simulation tool can be used to study long-term frequency and voltage stability control of interconnected power systems.