Committed Carbon Emission Operation Region of Microgrids: Theory, Construction and Observation
Zhang Jiyue1, Ren Zhouyang1, Jiang Yunpeng1, Feng Jianbing1, Sun Yan2
1. National Key Laboratory of Power Transmission Equipment Technology Chongqing University Chongqing 400044 China; 2. Guangxi Power Grid Co. Ltd Nanning 530000 China
Abstract:Developing low-carbon microgrids with high-penetration renewable energy integration and exploiting low-carbon operational potential of microgrids are significant for achieving a green-oriented transition in the energy system. However, due to increasing source and load fluctuations in the actual environment, maintaining the expected optimal low-carbon regulation state becomes challenging for microgrids, greatly increasing the risk of excess carbon emissions and deviation from the safe operating region. Therefore, the theory and calculation method of Committed Carbon Emission Operation Region (CCEOR) for microgrids is proposed. The low carbon regulation ability of microgrids can be intuitively quantified through geometric features for dispatching centers by CCEOR projection observation, providing an effective tool for monitoring and sensing the operating state of microgrids. Firstly, the CCEOR model, which considers committed carbon emissions and sequential operation characteristics of microgrids, is established. The mathematical property of CCEOR is revealed from the view of boundary characteristics, ensuring observable theoretical conditions. Secondly, aiming at high-dimensional coupling features of CCEOR, a low-dimensional CCEOR observation model is constructed based on carbon emission flow theory. The low-carbon operation space of microgrids can be projected into the load space of key nodes. Accordingly, a boundary solution algorithm combining an improved second-order cone and convex hull relaxation method is proposed. The proposed method can effectively fit the boundary of low-dimensional CCEOR with practical fitting accuracy. Finally, the geometric feature indices are established to describe the low carbon operation capability and variable coupling relationship of microgrids, facilitating the quantitative evaluation of their low carbon regulation potential. Two microgrid test systems with different scales validate the proposed method. The observation and geometric feature evaluation of CCEOR shows that the current low carbon operation status and complex coupling relationship of different observation variables can be intuitively reflected. Besides, it is demonstrated that the renewable energy and carbon emission targets significantly impact the low-carbon operation space of microgrids. The overall CCEOR is expanded, and the microgrid has a flexible adjustment space with the increase of renewable energy penetration. In addition, the renewable energy access location affects the coupling degree between different observed variables. With the increase of carbon emission targets, safe operation conditions play a major role in limiting the load growth, ensuring the microgrid operates within a safe and feasible range. Compared with the existing common boundary fitting method, the proposed boundary fitting method has high construction accuracy and less calculation cost. The following conclusions can be drawn from the simulation results. (1) The observation and geometric feature evaluation of CCEOR provides visual operation auxiliary judgment and quick perception of the operating state for dispatchers by reflecting the current low carbon operation status and the complex coupling relationship of different observation variables. (2) The proposed boundary fitting method of CCEOR balances CCEOR construction accuracy and computational cost. (3) CCEOR has a good application prospect for guiding low- carbon resource optimization in microgrids, collaborating with the electric carbon market's distribution network and trading strategy.
[1] 李政, 陈思源, 董文娟, 等. 碳约束条件下电力行业低碳转型路径研究[J]. 中国电机工程学报, 2021, 41(12): 3987-4000. Li Zheng, Chen Siyuan, Dong Wenjuan, et al.Low carbon transition pathway of power sector under carbon emission constraints[J]. Proceedings of the CSEE, 2021, 41(12): 3987-4000. [2] 闫佳佳, 滕云, 邱实, 等. 计及供能可靠性动态约束与碳减排的充能型微电网互联系统优化模型[J]. 电工技术学报, 2022, 37(23): 5956-5975. Yan Jiajia, Teng Yun, Qiu Shi, et al.Optimization model of charging microgrid interconnection system considering dynamic constraints of energy supply reliability and carbon emission reduction[J]. Transa- ctions of China Electrotechnical Society, 2022, 37(23): 5956-5975. [3] 赵毅, 于继来. 多微网智能配电系统协同自律运控模式初探[J]. 电网技术, 2018, 42(4): 1200-1209. Zhao Yi, Yu Jilai.Preliminary research on operation and control model of coordination and self-discipline for smart distribution system with multi microgrids[J]. Power System Technology, 2018, 42(4): 1200-1209. [4] Cao J, Crozier C, McCulloch M, et al. Optimal design and operation of a low carbon community based multi-energy systems considering EV integration[J]. IEEE Transactions on Sustainable Energy, 2019, 10(3): 1217-1226. [5] 王琦, 李宁, 顾欣, 等. 考虑碳减排的综合能源服务商合作运行优化策略[J]. 电力系统自动化, 2022, 46(7): 131-140. Wang Qi, Li Ning, Gu Xin, et al.Optimization strategy for cooperative operation of integrated energy service providers considering carbon emission reduction[J]. Automation of Electric Power Systems, 2022, 46(7): 131-140. [6] 顾欣, 王琦, 胡云龙, 等. 基于纳什议价的多微网综合能源系统分布式低碳优化运行策略[J]. 电网技术, 2022, 46(4): 1464-1475. Gu Xin, Wang Qi, Hu Yunlong, et al. Distributed low-carbon optimal operation strategy of multi- microgrids integrated energy system based on Nash Bargaining[J]. Power System Technology, 2022, 46(4): 1464-1475, 32-38. [7] 刘英培, 黄寅峰. 考虑碳排权供求关系的多区域综合能源系统联合优化运行[J]. 电工技术学报, 2023, 38(13): 3459-3472. Liu Yingpei, Huang Yinfeng.Joint optimal operation of multi-regional integrated energy system con- sidering the supply and demand of carbon emission rights[J]. Transactions of China Electrotechnical Society, 2023, 38(13): 3459-3472. [8] 乔学博, 杨志祥, 李勇, 等. 计及两级碳交易和需求响应的多微网合作运行优化策略[J]. 高电压技术, 2022, 48(7): 2573-2583. Qiao Xuebo, Yang Zhixiang, Li Yong, et al.Optimi- zation strategy for cooperative operation of multi- microgrids considering two-level carbon trading and demand response[J]. High Voltage Engineering, 2022, 48(7): 2573-2583. [9] 刘哲远, 邢海军, 程浩忠, 等. 考虑碳排放流及需求响应的综合能源系统双层优化调度[J]. 高电压技术, 2023, 49(1): 169-178. Liu Zheyuan, Xing Haijun, Cheng Haozhong, et al.Bi-level optimal scheduling of integrated energy system considering carbon emission flow and demand response[J]. High Voltage Engineering,2023, 49(1): 169-178. [10] Wang Meng, Yu Hang, Yang Yikun, et al.Unlocking emerging impacts of carbon tax on integrated energy systems through supply and demand co-optimization[J]. Applied Energy, 2021, 302: 117579. [11] 张笑演, 王橹裕, 黄蕾, 等. 考虑扩展碳排放流和碳交易议价模型的园区综合能源优化调度[J]. 电力系统自动化, 2023, 47(9): 34-46. Zhang Xiaoyan, Wang Luyu, Huang Lei, et al.Optimal dispatching of park-level integrated energy system considering augmented carbon emission flow and carbon trading bargain model[J]. Automation of Electric Power Systems, 2023, 47(9): 34-46. [12] Liu Yikui, Wu Lei, Chen Yonghong, et al.Integrating high DER-penetrated distribution systems into ISO energy market clearing: a feasible region projection approach[J]. IEEE Transactions on Power Systems, 2021, 36(3): 2262-2272. [13] 肖峻, 左磊, 祖国强, 等. 基于潮流计算的配电系统安全域模型[J]. 中国电机工程学报, 2017, 37(17): 4941-4949. Xiao Jun, Zuo Lei, Zu Guoqiang, et al.Model of distribution system security region based on power flow calculation[J]. Proceedings of the CSEE, 2017, 37(17): 4941-4949. [14] 肖峻, 祖国强, 白冠男, 等. 配电系统安全域的数学定义与存在性证明[J]. 中国电机工程学报, 2016, 36(18): 4828-4836. Xiao Jun, Zu Guoqiang, Bai Guannan, et al.Mathematical definition and existence proof of distribution system security region[J]. Proceedings of the CSEE, 2016, 36(18): 4828-4836. [15] 肖峻, 肖居承, 张黎元, 等. 配电网的严格与非严格安全边界[J]. 电工技术学报, 2019, 34(12): 2637-2648. Xiao Jun, Xiao Jucheng, Zhang Liyuan, et al.Strict and non-strict security boundary of distribution network[J]. Transactions of China Electrotechnical Society, 2019, 34(12): 2637-2648. [16] 肖峻, 曹严, 张宝强. 配电网安全域的凹凸性: 定理、证明及判定算法[J]. 中国电机工程学报, 2021, 41(15): 5153-5167. Xiao Jun, Cao Yan, Zhang Baoqiang.Concavity and convexity of distribution system security region: theorem, proof and determination algorithm[J]. Proceedings of the CSEE, 2021, 41(15): 5153-5167. [17] Liu Yanqi, Li Zhigang, Wu Q H, et al.Real-time dispatchable region of renewable generation con- strained by reactive power and voltage profiles in AC power networks[J]. CSEE Journal of Power and Energy Systems, 2019, 6(3): 528-536. [18] 徐华廷, 江博游, 冯斌, 等. 量化电网不确定性对调度计划影响的经济运行域概念及其凸包求解方法[J]. 中国电机工程学报, 2023, 43(16): 6288-6300. Xu Huating, Jiang Boyou, Feng Bin, et al.The concept of economic operating region and its convex hull solution method for quantifying the influence of grid uncertainty on scheduling plan[J]. Proceedings of the CSEE, 2023, 43(16): 6288-6300. [19] 王强钢, 林天皓, 吕旭明, 等. 计及火电阶梯式爬坡率的耦合系统相邻时刻有功可行域确定方法[J]. 中国电机工程学报, 2023, 43(20): 7789-7802. Wang Qianggang, Lin Tianhao, Lü Xuming, et al.Active power feasible region determination method of coupled system at adjacent moments considering ladder-type ramp rate of thermal power units[J]. Proceedings of the CSEE, 2023, 43(20): 7789-7802. [20] 姜涛, 李雪, 李国庆, 等. 含多端柔性直流的交直流电力系统静态电压稳定域构建方法[J]. 电工技术学报, 2022, 37(7): 1746-1759. Jiang Tao, Li Xue, Li Guoqing, et al.A predictor- corrector algorithm for forming voltage stability region of hybrid AC/DC power grid with inclusion of VSC-MTDC[J]. Transactions of China Electro- technical Society, 2022, 37(7): 1746-1759. [21] 林伟, 杨知方, 余娟, 等. 考虑机组启停的省间电量交易可行域确定方法[J]. 中国电机工程学报, 2021, 41(15): 5119-5128. Lin Wei, Yang Zhifang, Yu Juan, et al.Determination on energy trading region among regional networks considering unit commitment[J]. Proceedings of the CSEE, 2021, 41(15): 5119-5128. [22] 袁泉, 孙宇军, 张蔷, 等. 基于日前调度时段组合的联络线功率可行域分析[J]. 电网技术, 2023, 47(2): 636-647. Yuan Quan, Sun Yujun, Zhang Qiang, et al.Feasible region of tie-line capacity based on combination of day-ahead dispatching time intervals[J]. Power System Technology, 2023, 47(2): 636-647. [23] Lin Wei, Yang Zhifang, Yu Juan, et al.Tie-line security region considering time coupling[J]. IEEE Transactions on Power Systems, 2021, 36(2): 1274-1284. [24] 周天睿, 康重庆, 徐乾耀, 等. 电力系统碳排放流的计算方法初探[J]. 电力系统自动化, 2012, 36(11): 44-49. Zhou Tianrui, Kang Chongqing, Xu Qianyao, et al.Preliminary investigation on a method for carbon emission flow calculation of power system[J]. Auto- mation of Electric Power Systems, 2012, 36(11): 44-49. [25] 李姚旺, 张宁, 杜尔顺, 等. 基于碳排放流的电力系统低碳需求响应机制研究及效益分析[J]. 中国电机工程学报, 2022, 42(8): 2830-2842. Li Yaowang, Zhang Ning, Du Ershun, et al.Mechanism study and benefit analysis on power system low carbon demand response based on carbon emission flow[J]. Proceedings of the CSEE, 2022, 42(8): 2830-2842. [26] 李业辉, 李姚旺, 刘昱良, 等. 基于碳排放流迭代算法的分布式碳表系统(一): 理论方法与分析[J]. 电网技术, 2023, 47(6): 2165-2174. Li Yehui, Li Yaowang, Liu Yuliang, et al.Distributed carbon meter system based on iterative calculation of carbon emission flow (Ⅰ): theoretical method and analysis[J]. Power System Technology, 2023, 47(6): 2165-2174. [27] Gao Hongjun, Liu Junyong, Wang Lingfeng.Robust coordinated optimization of active and reactive power in active distribution systems[J]. IEEE Transactions on Smart Grid, 2018, 9(5): 4436-4447. [28] 彭克, 王成山, 李琰, 等. 典型中低压微电网算例系统设计[J]. 电力系统自动化, 2011, 35(18): 31-35. Peng Ke, Wang Chengshan, Li Yan, et al.Design of a typical medium-low voltage microgrid network[J]. Automation of Electric Power Systems, 2011, 35(18): 31-35. [29] Chen Sheng, Wei Zhinong, Sun Guoqiang, et al.Convex hull based robust security region for electricity- gas integrated energy systems[J]. IEEE Transactions on Power Systems, 2019, 34(3): 1740-1748. [30] 罗潇, 任洲洋, 温紫豪, 等. 考虑氢能系统热回收的电氢区域综合能源系统日前优化运行[J]. 电工技术学报, 2023, 38(23): 6359-6372. Luo Xiao, Ren Zhouyang, Wen Zihao, et al.A day-ahead dispatching method of regional integrated electric-hydrogen energy systems considering the heat recycle of hydrogen systems[J]. Transactions of China Electrotechnical Society, 2023, 38(23): 6359-6372. [31] 何晨可, 朱继忠, 刘云, 等. 计及碳减排的电动汽车充换储一体站与主动配电网协调规划[J]. 电工技术学报, 2022, 37(1): 92-111. He Chenke, Zhu Jizhong, Liu Yun, et al.Coordinated planning of electric vehicle charging-swapping- storage integrated station and active distribution network considering carbon reduction[J]. Transa- ctions of China Electrotechnical Society, 2022, 37(1): 92-111.