Kun Yang, Yulong Deng, Chunyan Li, Derong Yi, Yang Liu, Bo Hu, Changzhen Shao
{"title":"Optimized operation of integrated electricity-HCNG systems with distributed hydrogen injecting","authors":"Kun Yang, Yulong Deng, Chunyan Li, Derong Yi, Yang Liu, Bo Hu, Changzhen Shao","doi":"10.1049/gtd2.13222","DOIUrl":"https://doi.org/10.1049/gtd2.13222","url":null,"abstract":"<p>Green hydrogen, the cleanest energy carrier, is receiving increased attention in recent years. Transporting hydrogen through a natural gas system (NGS) will significantly promote the use of hydrogen, moreover, hydrogen-enriched compressed natural gas (HCNG) has great potential for renewable energy accommodation. To solve the problem of altered gas flow caused by hydrogen injection into natural gas networks, an optimized operation model of integrated electricity-HCNG systems (IEHCNGS) with distributed hydrogen injecting is proposed in this paper. Firstly, a calculating model of hydrogen volume fraction based on minimum square summation and depth-first search is established to describe the gas flow distribution of NGS accurately. Secondly, a quantitative method of gas supply reliability based on maximum entropy is proposed to ensure the safe operation of the system. Finally, an optimization model of IEHCNGS is established considering the coupling constraints of the integrated system and the reliability of NGS. The case study shows that the hydrogen volume fraction calculation model can correct the heat value of gas in each pipeline in real-time, the maximum entropy model helps to improve the gas supply reliability of NGS, and the distributed hydrogen injecting mode is more capable of accommodating renewable energy.</p>","PeriodicalId":13261,"journal":{"name":"Iet Generation Transmission & Distribution","volume":"18 18","pages":"2897-2909"},"PeriodicalIF":2.0,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/gtd2.13222","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142174329","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Disturbance observer-based finite-time control of a photovoltaic-battery hybrid power system","authors":"Fatemeh Esmaeili, Hamid Reza Koofigar","doi":"10.1049/gtd2.13248","DOIUrl":"https://doi.org/10.1049/gtd2.13248","url":null,"abstract":"<p>Herein, the load power control of the stand-alone photovoltaic-battery hybrid power system (HPS) has been investigated. The underlying HPS consists of a boost DC-DC converter, a non-isolated bidirectional half-bridge converter, a photovoltaic (PV) panel, and a battery pack. On the PV side, a disturbance observer-based finite-time terminal sliding mode control (FTSMC) is used to regulate the DC bus to the desired voltage, in the presence of irradiation variation and load changes. On the battery side, the load power control system is constructed, based on a model predictive control (MPC) algorithm, with constraints on state-of-charge (SOC) and maximum current value of the battery to improve the battery life cycle and high reliability of the system. To highlight the benefits of the closed-loop system, the analytical proofs and numerical analysis are presented from a comparative viewpoint. The experimentally derived results, by implementation on TMS320F28335 digital signal processing (DSP), are also presented and discussed for practical justification.</p>","PeriodicalId":13261,"journal":{"name":"Iet Generation Transmission & Distribution","volume":"18 18","pages":"2987-2998"},"PeriodicalIF":2.0,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/gtd2.13248","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142174327","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Dynamic partitioning of island smart distribution systems in emergencies","authors":"Zahra Hosseini Najafabadi, Asghar Akbari Foroud","doi":"10.1049/gtd2.13242","DOIUrl":"https://doi.org/10.1049/gtd2.13242","url":null,"abstract":"<p>When a severe fault occurs in the distribution network, all or parts of it may be disconnected from the upstream network. Partitioning of these islanded areas is a solution to supplying the affected loads. Due to the variable nature of loads and renewable distributed generation (DG), the static model of partitioning with a fixed nature during island operation cannot be suitable. Therefore, in this article, considering the variable nature of loads and renewable distributed generation, a dynamic model is presented for the island partitioning to restore more valuable loads, which is suitable for quick decision-making in emergencies. Also, a method for deciding on the mode of charging and discharging storage systems in emergencies is proposed. This model considers time limitation, uncontrollable DGs, controllable DGs and their control, controllability, and priority of loads, tie-switches, storage systems, simultaneous faults, different situations of unintentional islanding of the distribution network, position of switches, and variable nature of loads and distributed generations. So, it is more comprehensive than the previous methods. Applying the proposed model to the modified IEEE 69-bus system with controllable and uncontrollable generation and storage systems assuming different scenarios shows the effectiveness of the proposed scheme.</p>","PeriodicalId":13261,"journal":{"name":"Iet Generation Transmission & Distribution","volume":"18 18","pages":"2910-2929"},"PeriodicalIF":2.0,"publicationDate":"2024-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/gtd2.13242","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142174164","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Siying Chen, Yingbiao Li, Shun Li, Cong Fu, Yixing Chen, Lu Miao, Bo Bao
{"title":"DC overvoltage suppression method of wind farm connected via MMC-HVDC system","authors":"Siying Chen, Yingbiao Li, Shun Li, Cong Fu, Yixing Chen, Lu Miao, Bo Bao","doi":"10.1049/gtd2.13253","DOIUrl":"https://doi.org/10.1049/gtd2.13253","url":null,"abstract":"<p>A new integration strategy of grid-forming-controlled wind farms connected to the bulk power systems through high-voltage direct current transmission based on the modular multi-level converter (MMC) is proposed to solve the problem of traditional uncontrollable DC overvoltage during the short circuit faults at the receiving end. However, a new DC overvoltage phenomenon appears after the fault is cleared, and the interaction between the wind farm and sending- and receiving-end MMCs makes the DC overvoltage mechanism more complex; further exploration shows that DC overvoltage during the sending-end fault recovery stage occurs under the new integration strategy. Therefore, the evolution process and mechanism of the new DC overvoltage are analysed. It is found that affected by the interaction between wind farms and MMCs, the alternate saturation of the integrators in the PI controller of MMCs is the main cause. Based on this understanding, additional controls are proposed to suppress this DC overvoltage during the fault recovery stage. Simulations are carried out on a test with MATLAB/Simulink, and the results verify the efficacy of the proposed methods in suppressing DC overvoltage.</p>","PeriodicalId":13261,"journal":{"name":"Iet Generation Transmission & Distribution","volume":"18 19","pages":"3052-3058"},"PeriodicalIF":2.0,"publicationDate":"2024-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/gtd2.13253","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142430128","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Distributionally robust sequential load restoration of distribution system considering random contingencies","authors":"Yangwu Shen, Feifan Shen, Heping Jin, Ziqian Li, Zhongchu Huang, Yunyun Xie","doi":"10.1049/gtd2.13155","DOIUrl":"https://doi.org/10.1049/gtd2.13155","url":null,"abstract":"<p>Natural disasters would destroy power grids and lead to blackouts. To enhance resilience of distribution systems, the sequential load restoration strategy can be adopted to restore outage portions using a sequence of control actions, such as switch on/off, load pickup, distributed energy resource dispatch etc. However, the traditional strategy may be unable to restore the distribution system in extreme weather events due to random sequential contingencies during the restoration process. To address this issue, this paper proposes a distributionally robust sequential load restoration strategy to determine restoration actions. Firstly, a novel multi-time period and multi-zone contingency occurrence uncertainty set is constructed to model spatial and temporal nature of sequential line contingencies caused by natural disasters. Then, a distributionally robust load restoration model considering uncertain line contingency probability distribution is formulated to maximize the expected restored load amount with respect to the worst-case line contingency probability distribution. Case studies were carried out on the modified IEEE 123-node system. Simulation results show that the proposed distributionally robust sequential load restoration strategy can produce a more resilient load restoration strategy against random sequential contingencies. Moreover, as compared with the conventional robust restoration strategy, the proposed strategy yields a less conservative restoration solution.</p>","PeriodicalId":13261,"journal":{"name":"Iet Generation Transmission & Distribution","volume":"18 18","pages":"2885-2896"},"PeriodicalIF":2.0,"publicationDate":"2024-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/gtd2.13155","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142174255","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yuying Zhang, Chen Liang, Han Wang, Jiayi Zhang, Bo Zeng, Wenxia Liu
{"title":"A multi-objective interval optimization approach to expansion planning of active distribution system with distributed internet data centers and renewable energy resources","authors":"Yuying Zhang, Chen Liang, Han Wang, Jiayi Zhang, Bo Zeng, Wenxia Liu","doi":"10.1049/gtd2.13249","DOIUrl":"https://doi.org/10.1049/gtd2.13249","url":null,"abstract":"<p>With the development of the digital economy, the power demand for data centers (DCs) is rising rapidly, which presents a challenge to the economic and low-carbon operation of the future distribution system. To this end, this paper fully considers the multiple flexibility of DC and its impact on the active distribution network, and establishes a collaborative planning model of DC and active distribution network. Differing from most existing studies that apply robust optimization or stochastic optimization for uncertainty characterization, this study employs a novel interval optimization approach to capture the inherent uncertainties within the system (including the renewable energy source (RES) generation, electricity price, electrical loads, emissions factor and workloads). Subsequently, the planning model is reformulated as the interval multi-objective optimization problem (IMOP) to minimize economic cost and carbon emission. On this basis, instead of using a conventional deterministic-conversion approach, an interval multi-objective optimization evolutionary algorithm based on decomposition (IMOEA/D) is proposed to solve the proposed IMOP, which is able to fully preserve the uncertainty inherent in interval-typed information and allow to obtain an interval-formed Pareto front for risk-averse decision-making. Finally, an IEEE 33-node active distribution network is utilized for simulation and analysis to confirm the efficacy of the proposed approach.</p>","PeriodicalId":13261,"journal":{"name":"Iet Generation Transmission & Distribution","volume":"18 18","pages":"2999-3016"},"PeriodicalIF":2.0,"publicationDate":"2024-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/gtd2.13249","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142174157","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Research on live detection technology of distribution network cable insulation deterioration state based on harmonic components","authors":"Ran Hu, Haisong Xu, Xu Lu, Anzhe Wang, Zhifeng Xu, Yuli Wang, Daning Zhang","doi":"10.1049/gtd2.13238","DOIUrl":"https://doi.org/10.1049/gtd2.13238","url":null,"abstract":"<p>Due to the limitations imposed by urban power grid outages for maintenance, on-line harmonic current detection technology for distribution network cables is expected to become an effective supplement to traditional offline diagnostic methods, enhancing the real-time diagnosis of distribution network cable insulation conditions. This study established a 10 kV distribution network cable test platform and prepared typical defective cables subjected to moisture and long-term thermal aging. Using COMSOL finite element electromagnetic simulation, the magnetic flux evolution laws of the cable insulation under typical defects were obtained. Experimental tests provided the harmonic current characteristics and statistical features of cables with typical defects. Based on these data, a method for analysing the degradation degree of distribution network cables was constructed using least absolute shrinkage and selection operator (LASSO) regression analysis. Furthermore, a defect-type identification method based on cluster analysis was proposed. Results indicate that the odd harmonics and the 4th harmonic of the distribution network cable's harmonic current are closely related to the cable's degradation state. A model integrating principal component analysis (PCA) data dimensionality reduction and expectation-maximization clustering analysis achieved a recognition accuracy of up to 75.64% in distinguishing between moisture-affected and normal cable states. The proposed on-line detection and evaluation methods can effectively identify high-risk cables with latent defects.</p>","PeriodicalId":13261,"journal":{"name":"Iet Generation Transmission & Distribution","volume":"18 17","pages":"2847-2859"},"PeriodicalIF":2.0,"publicationDate":"2024-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/gtd2.13238","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142123382","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Shunlin Zheng, Yaliang Liu, Yi Sun, Xinpeng Mo, Liming Feng, Xinya Liu, Quan Chao, Wangzhang Cao
{"title":"Integrated demand response optimization strategy considering risk appetite under multi-dimensional uncertain information","authors":"Shunlin Zheng, Yaliang Liu, Yi Sun, Xinpeng Mo, Liming Feng, Xinya Liu, Quan Chao, Wangzhang Cao","doi":"10.1049/gtd2.13245","DOIUrl":"https://doi.org/10.1049/gtd2.13245","url":null,"abstract":"<p>Integrated demand response (IDR) is deemed as an effective tool to balance energy supply and demand. User’s uncertain information containing prior uncertain information and posterior uncertain information is a key factor affecting the implementation effectiveness of IDR, but existing studies fail to consider the two types of uncertain information, response risk caused by the uncertain information, and risk appetite comprehensively. Based on the principal-agent theory of optimal incentive contract under uncertain information and Markowitz's mean-variance portfolio theory, a new IDR model is established in this paper, and an IDR optimization strategy considering risk appetite under uncertain information is proposed. By proposing the user model considering multi-dimensional uncertain information and the risk appetite-based integrated energy service providers (IESP) model based on the principal-agent theory and Markowitz's mean-variance portfolio theory, we have achieved effective modelling of the user’s uncertain information and the risk borne by IESP. The arithmetic examples have verified advantages of the model in enhancing the accuracy of user’s actual response prediction and the superiority of incentive strategies, which is beneficial to reduce the cost of IESPs and enhance the benefit of users participating in IDR.</p>","PeriodicalId":13261,"journal":{"name":"Iet Generation Transmission & Distribution","volume":"18 18","pages":"2956-2971"},"PeriodicalIF":2.0,"publicationDate":"2024-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/gtd2.13245","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142174210","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Analysis of hybrid AC/DC transmission system: A Turkey case study","authors":"Eda Karaca, Fatih Mehmet Nuroğlu","doi":"10.1049/gtd2.13247","DOIUrl":"https://doi.org/10.1049/gtd2.13247","url":null,"abstract":"<p>The need to transmit energy in the most effective way arises in parallel with the demand for energy in developing countries. As the amount of transmitted power increases, transmission lines can become overloaded, causing a blackout. This study aims to increase the transmission capacity without experiencing right-of-way problems by converting Turkey's existing high voltage AC systems to hybrid AC/DC systems. With such a design, it is aimed at providing more efficient and continuous transmission by using the high-voltage DC system's low-loss feature at long distances. Using the 400 kV double circuit line structure, the existing electricity transmission system is modelled using real data in the DigSILENT PowerFactory. The electromagnetic fields that will occur due to the use of AC and DC circuits on the same tower in such a transformation situation are analysed with FEMM 4.2, based on the finite element method. The compliance of the electromagnetic fields that will occur with the use of hybrid 400 kV AC and 500 kV DC was determined in the study. In addition, according to the simulation results, it is predicted that in the case of hybrid AC/DC transmission, the current transmission capacity would increase and the losses would decrease.</p>","PeriodicalId":13261,"journal":{"name":"Iet Generation Transmission & Distribution","volume":"18 18","pages":"3017-3028"},"PeriodicalIF":2.0,"publicationDate":"2024-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/gtd2.13247","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142174209","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Improve conservation voltage regulation effects by integrating more distributed renewable generations","authors":"Ang Li, Jin Zhong","doi":"10.1049/gtd2.13195","DOIUrl":"https://doi.org/10.1049/gtd2.13195","url":null,"abstract":"<p>Due to intermittent renewable energy and fluctuating load demand, distribution networks with renewable distributed generation (DG) installations are more likely to suffer voltage issues and significant power losses. The performance of conservation voltage regulation (CVR) schemes may be adversely affected by the undesirable voltage profile at specific nodes. This paper aims to reduce power losses in CVR-implemented networks by optimally planning new renewable DGs without changing the existing ones. A scenario-based optimal renewable DG planning model is proposed with a novel scenario formation method. The uncertainties of load demand and renewables are captured jointly and formed into a finite number of scenarios based on a multivariate Gaussian mixture model (MultiGMM). The locations and capacities of different types of new renewable DGs are optimally planned for CVR performance improvements on power loss saving by aggregating the operation status and probabilities of the scenarios using mixed-integer non-linear programming (MINLP). A time-series simulation is formulated for accuracy verification. The results of case studies show that the proposed model can significantly reduce power losses, active load demand, and reactive load demand. The accuracy of the planning results can be guaranteed with fewer scenarios compared to a widely used classical scenario-based planning method.</p>","PeriodicalId":13261,"journal":{"name":"Iet Generation Transmission & Distribution","volume":"18 17","pages":"2747-2760"},"PeriodicalIF":2.0,"publicationDate":"2024-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/gtd2.13195","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142123144","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}