Network Planning of AC/DC Hybrid Distribution System Based on Linearization Method
Jiang Yuewen1, Luo Zeyu2, Cheng Nuo3
1. Fujian Province University Engineering Research Center of Smart Distribution Grid (Fuzhou University) Fuzhou 350116 China; 2. College of Electrical Engineering and Automation Fuzhou University Fuzhou 350116 China; 3. State Grid Fujian Economic Research Institute Fuzhou 350012 China
Abstract:In order to adapt the network structure of a distribution network to the access of new energy technologies such as distributed generation (DG), energy storage and DC loads, a new network planning method for AC/DC hybrid distribution networks is proposed. The method considered all possibilities of the AC/DC configuration to improve the economic benefits of the network construction, and constructed a linearized single-layer network planning model to improve the global optimization capability in view of the difficulty of obtaining global optimal solutions for the network planning model. Firstly, considering that AC/DC types of buses and the connection states between buses determine the investment cost of converters and lines, which determines the economic benefits of distribution network planning, a binary bus type matrix is used to represent AC/DC types of buses, a binary network association matrix is developed to represent the connection states between buses, and binary line type variables are adopoted to represent line type selection to construct network structure decision variables, achieving a description of the overall network structure. Secondly, with an objective of converter installation cost, line construction cost and system operation and maintenance cost, a single-layer network planning model is established considering elaborated and practical constraints, such as the number of node-connected lines, line selection constraint, power flow, voltage source converter (VSC) reactive power compensation capacity, system safety operation, energy storage operation, network connectivity and so on. In this proposed model, the AC and DC current models is unified by introducing branch type variables, thus linking the planning layer and operation layer, so that network planning variables and operation optimization variables consisting of power purchased from the distribution network to the grid, DG output, energy storage charging and discharging power and VSC power were optimized simultaneously to enhance the possibility of obtaining a global optimal solution. Finally, to achieve better sulution, power flow equations and line transmission capacity constraints are linearized by a series of linearization methods, such that the mixed integer nonlinear programming (MINLP) problem was transformed into a mixed integer linear programming (MILP) problem, and the GUROBI solver is invoked in Matlab to solve it. The validity of the planning method was verified in a 13-node distribution system. The simulation results show that: (1) The AC/DC hybrid distribution network planning scheme can save 5.05% of the total investment and operation cost compared with the pure AC distribution network planning, and the network structure of the planned AC/DC hybrid distribution network also has greater network supply capacity, which illustrates that the AC/DC hybrid distribution network is more advantageous in the case of mixed AC/DC sources and loads. (2) The proposed planning method saves 13.54% of the total investment and operation cost and 91.32% of the computation time compared with the traditional bi-layer planning model solved by genetic algorithm, which indicates that the single-layer network planning method has prominent global optimization performance and faster computational efficiency. (3) As the method does not require relaxation of constraints, compared to second-order cone planning techniques, there are no limitations in terms of grid topology, etc, and it is suitable for the planning of both radial and meshed distribution networks.
江岳文, 罗泽宇, 程诺. 基于线性化方法的交直流混合配电系统网架规划[J]. 电工技术学报, 2024, 39(5): 1404-1418.
Jiang Yuewen, Luo Zeyu, Cheng Nuo. Network Planning of AC/DC Hybrid Distribution System Based on Linearization Method. Transactions of China Electrotechnical Society, 2024, 39(5): 1404-1418.
[1] Ahmed H M A, Eltantawy A B, Salama M M A. A planning approach for the network configuration of AC-DC hybrid distribution systems[J]. IEEE Transactions on Smart Grid, 2018, 9(3): 2203-2213. [2] 李幸芝, 韩蓓, 李国杰, 等. 考虑非高斯耦合不确定性的交直流配电网两阶段概率状态估计[J]. 电工技术学报, 2020, 35(23): 4949-4960. Li Xingzhi, Han Bei, Li Guojie, et al.Two-stage probabilistic state estimation for AC/DC distribution network considering non-gaussian coupling uncertainties[J]. Transactions of China Electrotechnical Society, 2020, 35(23): 4949-4960. [3] 徐少博, 徐永海, 陶顺, 等. 计及边带分量频率耦合的电压源型换流器输入导纳建模[J]. 电工技术学报, 2023, 38(11): 2883-2893. Xu Shaobo, Xu Yonghai, Tao Shun, et al.Voltage source converter input admittance model considering frequency coupling of sideband components[J]. Transactions of China Electrotechnical Society, 2023, 38(11): 2883-2893. [4] 涂小涛, 高仕龙, 陈锐, 等. 多端柔性交直流混合配电网建模及仿真分析[J]. 电器与能效管理技术, 2020(1): 58-63. Tu Xiaotao, Gao Shilong, Chen Rui, et al.Modeling and simulation analysis of multi-terminal flexible AC/DC hybrid distribution network[J]. Electrical & Energy Management Technology, 2020(1): 58-63. [5] 罗志刚, 韦钢, 袁洪涛, 等. 基于区间直觉模糊理论的直流配网规划方案综合决策[J]. 电工技术学报, 2019, 34(10): 2011-2021. Luo Zhigang, Wei Gang, Yuan Hongtao, et al.Comprehensive decision of DC distribution network planning based on interval intuitionistic fuzzy theory[J]. Transactions of China Electrotechnical Society, 2019, 34(10): 2011-2021. [6] 曹文远, 韩民晓, 谢文强, 等. 交直流配电网逆变器并联控制技术研究现状分析[J]. 电工技术学报, 2019, 34(20): 4226-4241. Cao Wenyuan, Han Minxiao, Xie Wenqiang, et al.Analysis on research status of parallel inverters control technologies for AC/DC distribution network[J]. Transactions of China Electrotechnical Society, 2019, 34(20): 4226-4241. [7] 郑重, 苗世洪, 李超, 等. 面向微型能源互联网接入的交直流配电网协同优化调度策略[J]. 电工技术学报, 2022, 37(1): 192-207. Zheng Zhong, Miao Shihong, Li Chao, et al.Coordinated optimal dispatching strategy of AC/DC distribution network for the integration of micro energy Internet[J]. Transactions of China Electrotechnical Society, 2022, 37(1): 192-207. [8] 葛少云, 张有为, 刘洪, 等. 考虑网架动态重构的主动配电网双层扩展规划[J]. 电网技术, 2018, 42(5): 1526-1536. Ge Shaoyun, Zhang Youwei, Liu Hong, et al.Bi-layer expansion programming method for active distribution network considering dynamic grid reconfiguration[J]. Power System Technology, 2018, 42(5): 1526-1536. [9] 方陈, 张翔, 程浩忠, 等. 主动管理模式下含分布式发电的配电网网架规划[J]. 电网技术, 2014, 38(4): 823-829. Fang Chen, Zhang Xiang, Cheng Haozhong, et al.Framework planning of distribution network containing distributed generation considering active management[J]. Power System Technology, 2014, 38(4): 823-829. [10] 曾顺奇, 汤森垲, 程浩忠, 等. 考虑源网荷储协调优化的主动配电网网架规划[J]. 南方电网技术, 2018, 12(3): 35-43. Zeng Shunqi, Tang Senkai, Cheng Haozhong, et al.Framework planning of active distribution network considering coordinated optimization of generation, network, load and storage[J]. Southern Power System Technology, 2018, 12(3): 35-43. [11] 胡晓博. 含分布式能源的交直流混合配电网规划[D]. 北京: 华北电力大学, 2017. [12] 王伟. 交直流配电网网架优化规划及典型应用场景研究[D]. 北京: 北京交通大学, 2018. [13] 李桂鑫, 葛磊蛟, 陶永晋, 等. 考虑分布式能源综合利用的交直流混合配电网规划研究[J]. 可再生能源, 2020, 38(1): 98-103. Li Guixin, Ge Leijiao, Tao Yongjin, et al.Research on the planning of AC/DC hybrid distribution network considering the comprehensive utilization of distributed energy[J]. Renewable Energy Resources, 2020, 38(1): 98-103. [14] 金国彬, 刘玉龙, 李国庆, 等. 考虑可靠性的交直流混合配电网网架与分布式电源协同优化规划[J]. 电力系统保护与控制, 2022, 50(22): 59-70. Jin Guobin, Liu Yulong, Li Guoqing, et al.Collaborative optimization planning of an AC/DC hybrid distribution network frame and distributed power generation considering reliability[J]. Power System Protection and Control, 2022, 50(22): 59-70. [15] Feng Wang, Tuan L A, Tjernberg L B, et al.A new approach for benefit evaluation of multiterminal VSC-HVDC using A proposed mixed AC/DC optimal power flow[J]. IEEE Transactions on Power Delivery, 2014, 29(1): 432-443. [16] 刘向龙, 刘友波, 尹航, 等. 含电力电子变压器的交直流混合配电系统网架结构规划[J]. 高电压技术, 2021, 47(4): 1283-1295. Liu Xianglong, Liu Youbo, Yin Hang, et al.Network planning of AC/DC hybrid distribution system with power electronic transformers[J]. High Voltage Engineering, 2021, 47(4): 1283-1295. [17] 韦涛, 苏剑, 崔艳妍, 等. 交直流混合配电网VSC与分布式电源三层协调规划方法研究[J]. 可再生能源, 2021, 39(9): 1263-1270. Wei Tao, Su Jian, Cui Yanyan, et al.Research on the three-level coordination planning method of hybrid AC/DC distribution network based on VSC and distributed generator[J]. Renewable Energy Resources, 2021, 39(9): 1263-1270. [18] 汪慧敏, 杨苹, 余雁琳. 基于双层粒子群算法的主动配电网分布式电源规划[J]. 计算机与数字工程, 2021, 49(9): 1930-1935. Wang Huimin, Yang Ping, Yu Yanlin.Optimal distributed generation planning in active distribution network based on Bi-level particle swarm optimization algorithm[J]. Computer & Digital Engineering, 2021, 49(9): 1930-1935. [19] 吴熙, 陆瑶, 蔡晖, 等. 计及风电不确定性的含线间潮流控制器的电力系统经济调度[J]. 电工技术学报, 2023, 38(3): 781-792. Wu Xi, Lu Yao, Cai Hui, et al.Economic dispatching of power system with interline power flow controller considering wind power uncertainty[J]. Transactions of China Electrotechnical Society, 2023, 38(3): 781-792. [20] 黄志强, 陈业伟, 毛志鹏, 等. 柔性多状态开关与分布式储能系统联合接入规划[J]. 电力系统自动化, 2022, 46(14): 29-37. Huang Zhiqiang, Chen Yewei, Mao Zhipeng, et al.Joint access planning of soft open point and distributed energy storage system[J]. Automation of Electric Power Systems, 2022, 46(14): 29-37. [21] Jabr R A.Radial distribution load flow using conic programming[J]. IEEE Transactions on Power Systems, 2006, 21(3): 1458-1459. [22] 刘一兵, 吴文传, 张伯明, 等. 基于混合整数二阶锥规划的主动配电网有功-无功协调多时段优化运行[J]. 中国电机工程学报, 2014, 34(16): 2575-2583. Liu Yibing, Wu Wenchuan, Zhang Boming, et al.A mixed integer second-order cone programming based active and reactive power coordinated multi-period optimization for active distribution network[J]. Proceedings of the CSEE, 2014, 34(16): 2575-2583. [23] 马鑫, 郭瑞鹏, 王蕾, 等. 基于二阶锥规划的交直流主动配电网日前调度模型[J]. 电力系统自动化, 2018, 42(22): 144-150. Ma Xin, Guo Ruipeng, Wang Lei, et al.Day-ahead scheduling model for AC/DC active distribution network based on second-order cone programming[J]. Automation of Electric Power Systems, 2018, 42(22): 144-150. [24] Low S H.Convex relaxation of optimal power flow—part I: formulations and equivalence[J]. IEEE Transactions on Control of Network Systems, 2014, 1(1): 15-27. [25] Low S H.Convex relaxation of optimal power flow—part II: exactness[J]. IEEE Transactions on Control of Network Systems, 2014, 1(2): 177-189. [26] 郑扬威, 江岳文, 张金辉. 高比例风电渗透下考虑长短期储能的源-储-输联合规划优化[J]. 电力自动化设备, 2023, 43(3): 63-71. Zheng Yangwei, Jiang Yuewen, Zhang Jinhui.Joint planning optimization of source-storage-transportation considering long- and short-term energy storage under high proportion of wind power penetration[J]. Electric Power Automation Equipment, 2023, 43(3): 63-71. [27] 范志成, 朱俊澎, 袁越, 等. 基于改进型直流潮流算法的主动配电网分布式电源规划模型及其线性化方法[J]. 电网技术, 2019, 43(2): 504-513. Fan Zhicheng, Zhu Junpeng, Yuan Yue, et al.Distributed generation planning model of active distribution network and linearization method based on improved DC power flow algorithm[J]. Power System Technology, 2019, 43(2): 504-513. [28] 刘晓林, 王旭, 蒋传文, 等. 计及VSC运行约束的交直流混合配电网分布式优化调度方法[J]. 电网技术, 2021, 45(3): 1089-1101. Liu Xiaolin, Wang Xu, Jiang Chuanwen, et al.Distributed optimal scheduling of hybrid AC-DC distribution grid considering VSC operation constraints[J]. Power System Technology, 2021, 45(3): 1089-1101. [29] Yeh H G, Gayme D F, Low S H.Adaptive VAR control for distribution circuits with photovoltaic generators[J]. IEEE Transactions on Power Systems, 2012, 27(3): 1656-1663. [30] 卫志农, 季聪, 孙国强, 等. 含VSC-HVDC的交直流系统内点法最优潮流计算[J]. 中国电机工程学报, 2012, 32(19): 89-95, 190. Wei Zhinong, Ji Cong, Sun Guoqiang, et al.Interior-point optimal power flow of AC-DC system with VSC-HVDC[J]. Proceedings of the CSEE, 2012, 32(19): 89-95, 190. [31] 高红均, 刘俊勇, 魏震波, 等. 主动配电网分层鲁棒规划模型及其求解方法[J]. 中国电机工程学报, 2017, 37(5): 1389-1401. Gao Hongjun, Liu Junyong, Wei Zhenbo, et al.A Bi-level robust planning model of active distribution network and its solution method[J]. Proceedings of the CSEE, 2017, 37(5): 1389-1401. [32] 王文超, 庞丹, 成龙, 等. 考虑电价型需求响应的交直流混合配电网优化调度[J]. 电网技术, 2019, 43(5): 1675-1682. Wang Wenchao, Pang Dan, Cheng Long, et al.Optimal dispatch approach for hybrid AC/DC distribution networks considering price-based demand response[J]. Power System Technology, 2019, 43(5): 1675-1682.