电工技术学报  2023, Vol. 38 Issue (7): 1765-1779    DOI: 10.19595/j.cnki.1000-6753.tces.211840
电力系统与综合能源 |
基于时空正交配置的电力-天然气互联系统最优校正控制方法
杜蕙1, 林涛1, 李轻言1, 张效宁2, 徐遐龄3
1.武汉大学电气与自动化学院 武汉 430072;
2.华北电力大学控制与计算机工程学院 北京 102206;
3.国家电网公司华中分部 武汉 430077
Optimal Corrective Control Method of Electricity and Natural Gas Interconnected Systems Based on Space-Time Orthogonal Collocation
Du Hui1, Lin Tao1, Li Qingyan1, Zhang Xiaoning2, Xu Xialing3
1. School of Electrical Engineering and Automation Wuhan University Wuhan 430072 China;
2. School of Control and Computer Engineering North China Electric Power University Beijing 102206 China;
3. Central China Branch of State Grid Cooperation Wuhan 430077 China
全文: PDF (2817 KB)   HTML
输出: BibTeX | EndNote (RIS)      
摘要 构建电力-天然气互联系统(EGIS)有助于促进能源结构转型,但同时造成了耦合系统间故障传播的风险。为消除EGIS中N-1故障造成的安全越限,防范连锁故障发生,该文提出一种基于时空正交配置(STOC)的EGIS最优校正控制方法。首先,针对偏微分方程描述的无限维气网动态管流模型,采用STOC在时空维度同时离散,转换为配置点处的有限维代数方程约束;然后,基于STOC气网动态管流约束和电网交流潮流约束,构建以校正控制代价最小为目标的安全约束最优能流模型,以获取最优校正控制策略;最后,通过算例验证了基于STOC方法与现有方法相比在精度和效率上的优越性,以及所得最优校正控制策略的有效性。所提方法在EGIS故障后具有在线辅助决策的应用潜力。
服务
把本文推荐给朋友
加入我的书架
加入引用管理器
E-mail Alert
RSS
作者相关文章
杜蕙
林涛
李轻言
张效宁
徐遐龄
关键词 电力-天然气互联系统最优校正控制安全约束最优能流气网动态管流时空正交配置    
Abstract:During the gradual implementation of the national energy transition and achieving the "emission peak and carbon neutral" target, renewable energy supported by fast-ramping gas-fired units and the ongoing global coal-to-gas transformation are effective ways to reduce carbon emissions in a short term. Construction of the electricity-gas interconnected systems (EGIS) promotes energy low-carbon transition. But meanwhile, it causes the potential risk of cascading failures between the coupling systems. Besides, compared to the instantaneous balance of electricity, the transient process of natural gas pipeline flow typically lasts from minutes to hours. Once it characterizes the time-dependent slow dynamic characteristics of the pipe flow, the EGIS optimization model is infinite-dimensional and hard to ensure computational accuracy and efficiency simultaneously. To this end, the paper proposes an EGIS optimal corrective control method based on space-time orthogonal collocation (STOC) for timely eliminating the security-limit violation caused by an N-1 fault in the EGIS.
Firstly, the STOC is used to discretize the partial-differential-equation-based infinite dynamic pipe flow model in space-time coordinates and transform it into a set of finite linear algebraic equations at the space-time collocation points. Compared with the traditional differential method, the STOC exhibits high computational accuracy and good numerical stability.
Secondly, based on the dynamic pipe flow of the gas network and the steady-state power flow of the power system, security constraints are established. And a security-constrained optimal energy flow (SCOEF) model is constructed to obtain the optimal corrective control strategy with the lowest control cost to eliminate the security-limit violation and restore the safe operation of the EGIS.
The computational performances of the STOC in accuracy and efficiency are compared with the Wendroff differential method based on a single section of the gas pipeline. More specifically, the coarse Wendroff model whose space-time differential mesh is 14×6 provides results with the worst accuracy performance after 1.503 5s calculation time. The dense Wendroff model whose space-time differential mesh is 52×18 provides results with the best accuracy performance after 12.734 4s calculation time. While the STOC whose space-time collocation mesh is 14×6 provides results with comparable accuracy performance to the dense Wendroff model after the shortest calculation time as 1.490 6s. In addition, the proposed SCOEF model is applied to solving the optimal corrective control strategy for an EGIS benchmark composed of the IEEE 118-bus power system and the Belgian 20-node gas network. The fault in the gas network causes the outage of pipeline 1-2 from delivering natural gas. The pipe flow of pipelines 1-2 is transferred to the remained parallel pipeline 1-2 and the mass flow rate (MFR) of the remained parallel pipeline 1-2 rapidly increased from 5.456 6Sm3/s to 10.876 4Sm3/s, which causes the inlet pressure rises sharply to 7.167 1MPa, far exceeding the security limit. Via the obtained corrective control strategy, namely generation curtailment of the gas-fired unit G66 in the power system, the MFR of pipeline 2-3 dropped from the original 9.656 0Sm3/s to 8.501 1Sm3/s, mitigating the over-limit gas pressure of the upstream pipeline 1-2 in the gas network. The transient gas pressures of the corresponding pipelines are all within the security limit under the obtained corrective control strategy.
Finally, the following conclusions can be drawn from the simulation analysis: (1) Compared with the Wendroff differential method, the STOC method has better computational performance when considering accuracy and efficiency comprehensively. (2) By solving the proposed SCOEF model, the obtained optimal corrective control strategy can effectively eliminate the security-limit violation caused by an N-1 fault in EGIS.
Future studies can be carried out on the distributed calculation of the proposed SCOEF model considering independence between the power system and gas network operators and also more refined nonlinear feature modeling of the EGIS coupling components.
Key wordsElectricity-gas interconnected systems (EGIS)    optimal corrective control    security-constrained optimal energy flow (SCOEF)    transient gas pipe flow    space-time orthogonal collocation (STOC)   
收稿日期: 2021-11-12     
PACS: TM744  
  TE09  
基金资助:国家自然科学基金联合基金重点资助项目(U2166206)
通讯作者: 林 涛 男,1969年生,教授,博士生导师,研究方向为电力系统运行及控制。E-mail:tlin@whu.edu.cn   
作者简介: 杜 蕙 女,1994年生,博士研究生,研究方向为电力系统运行及控制。E-mail:duhui1994@hotmail.com
引用本文:   
杜蕙, 林涛, 李轻言, 张效宁, 徐遐龄. 基于时空正交配置的电力-天然气互联系统最优校正控制方法[J]. 电工技术学报, 2023, 38(7): 1765-1779. Du Hui, Lin Tao, Li Qingyan, Zhang Xiaoning, Xu Xialing. Optimal Corrective Control Method of Electricity and Natural Gas Interconnected Systems Based on Space-Time Orthogonal Collocation. Transactions of China Electrotechnical Society, 2023, 38(7): 1765-1779.
链接本文:  
https://dgjsxb.ces-transaction.com/CN/10.19595/j.cnki.1000-6753.tces.211840          https://dgjsxb.ces-transaction.com/CN/Y2023/V38/I7/1765