摘要
线间潮流控制器(IPFC)拥有强大的潮流调控能力,可为解决大规模新能源接入背景下的潮流调控问题提供全新的解决方案。该文提出一种计及风电出力不确定性的含IPFC电力系统安全约束经济调度方法,首先基于MARKOV链生成风电出力场景,构建相应概率风险指标以描述系统安全性,并给出了兼顾经济性与安全性的优化目标函数;然后,在充分考虑双回线结构IPFC控制特性的情况下建立了故障前后电力系统的等式/不等式约束;最后,针对所建立的强非线性安全约束经济调度优化模型,设计了基于粒子群算法的计算构架并实现了模型的求解。基于江苏电网的算例分析表明,利用该文方法获得的策略比基于传统方法获得的策略能更好地满足潮流安全约束,且准确地计及了IPFC的控制特性,具有较高的应用价值。
Interline power flow controller(IPFC) proposed is a device with powerful power flow control ability, which provides a new method for power flow control under the increasing integration of large-scale renewable energy. In this paper, a security-constrained economic dispatching method for the power system with IPFC considering wind power uncertainty is proposed. Compared with the conventional method, the proposed method accurately considers the control characteristics of IPFC and can guarantee the security requirement under N-1 contingencies.Firstly, the optimization objective function considering both economy and security is expressed as Equ.(1)in this paper. The wind power output scenarios are predicted based on MARKOV chain, and the security objective function is expressed risk index R, which can be expressed by Equ.(2) in this paper.Furthermore, with full consideration of the control characteristics of IPFC with the double-circuit structure,the equality/inequality constraints of the power system before and after contingencies are established:1) N-1 contingency occurs on either series side of the IPFC of the double-circuit line. At this time, the converter of the primary line on the fault side loses its control while the converter of the other primary line can still play control functions. Take the N-1 contingency on line nj is taken as an example. At this time, the mathematical expression of control characteristics are Equ.(11) and Equ.(12) in this paper.2) N-1 contingency occurs on the non-IPFC series side. At this time, the power flow of the line controlled by IPFC remains unchanged before and after the fault. The mathematical expression is Equ.(13) in this paper.Finally, an improved particle swarm optimization algorithm is designed to solve the proposed optimization model with strong nonlinear constraints. In this structure, inequality constraints are treated by penalty function and equality constraints are guaranteed by power flow calculation. The particle velocity and position are constantly updated, and the optimal solution can be obtained after several iterations, that is, the optimal control scheme. The flow chart based on PSO is shown in Fig.4 in this paper.With the strategy obtained by the proposed method and the strategy without considering the IPFC control characteristics, the power flow in the Jiangsu power grid is compared, as shown in Fig.5 and Fig.6 respectively. It can be seen that the line load rate under the strategy obtained by the proposed method meets the security requirement whether the contingency occurs on the line controlled by IPFC or not. It indicates that the strategy obtained by the proposed method can meet the security requirement under N-1 contingencies and improve the static security of the system.The two dispatching strategies obtained by single scenario optimization and the optimization method in this paper are respectively applied to all wind power uncertainty scenarios. The comparison results of the line overload condition of two strategies when serious N-1 contingencies occur in some wind power scenarios are shown in Tab.2 in this paper. Under the background of large-scale wind power integration, the dispatching strategy considering the wind power scenario can satisfy the security constraints of power flow while the single-scenario dispatching strategy cannot.
作者
吴熙
陆瑶
蔡晖
王瑞
陈晟
Wu Xi;Lu Yao;Cai Hui;Wang Rui;Chen Sheng(Electrical Engineering College Southeast University,Nanjing 210096 China;Economic Research Institute State Grid Jiangsu Power Company,Nanjing 210008 China;Development Department State Grid Jiangsu Power Company,Nanjing 210024 China)
出处
《电工技术学报》
EI
CSCD
北大核心
2023年第3期781-792,共12页
Transactions of China Electrotechnical Society
基金
国家自然科学基金项目(52177075)
江苏省自然科学基金项目(BK20221466)
国网江苏省电力有限公司科技项目“基于线间潮流控制的新型FACTS装置协调规划技术与系统级运行控制策略研究”(J2021015)资助。
关键词
线间潮流控制器(IPFC)
双回线控制特性
风电场景
经济调度
Interline power flow controller(IPFC)
control characteristics for double-circuit
wind power scenario
economic dispatch
