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结肠癌组织中microRNA表达谱的变化 被引量:7
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作者 郑俊俊 毛玉娣 +2 位作者 汪朝靓 殷实 王华 《安徽医科大学学报》 CAS 北大核心 2019年第3期348-353,共6页
目的研究结肠癌组织中微小RNA(miRNA)表达谱的变化。方法收集5例结肠癌和5例癌旁组织进行miRNA基因芯片检测,从中筛选出异常表达的miRNA。通过生物信息学分析的方法对差异性表达miRNA所调控的靶基因、富集的生物过程和信号通路进行分析... 目的研究结肠癌组织中微小RNA(miRNA)表达谱的变化。方法收集5例结肠癌和5例癌旁组织进行miRNA基因芯片检测,从中筛选出异常表达的miRNA。通过生物信息学分析的方法对差异性表达miRNA所调控的靶基因、富集的生物过程和信号通路进行分析。结果通过Affymetrix miRNA4.0芯片检测,共筛选出73个差异性表达的miRNA,并对变化最明显的前13个上调及前13个下调的基因进行总结,其中包括hsa-miR-183-3p、hsa-miR-224-5p、hsa-miR-99a-5p等新的结肠癌相关基因。此外,生物信息学分析显示了差异性表达miRNA所调控的靶基因以及其所代表的生理意义,如蛋白质修饰过程、Wnt信号通路、癌症相关通路、翻译后蛋白质修饰、RAS信号通路、TP53转录调控等。结论检测结肠癌组织中miRNA表达谱的变化,对探讨结肠癌发病机制,寻找早期诊断和预后标志物,扩展治疗策略提供新的视野。 展开更多
关键词 结肠癌 mircoRNA 异常表达 基因表达谱 靶基因
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An approach to Iocational marginal price based zonal congestion management in deregulated electricity market 被引量:2
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作者 Md SARWAR Anwar Shahzad SIDDIQUI 《Frontiers in Energy》 SCIE CSCD 2016年第2期240-248,共9页
Congestion of transmission line is a vital issue and its management pose a technical challenge in power system deregulation. Congestion occurs in deregulated electricity market when transmission capacity is not suffic... Congestion of transmission line is a vital issue and its management pose a technical challenge in power system deregulation. Congestion occurs in deregulated electricity market when transmission capacity is not sufficient to simultaneously accommodate all constraints of power transmission through a line. Therefore, to manage congestion, a locational marginal price (LMP) based zonal congestion management approach in a deregulated elec- tricity market has been proposed in this paper. As LMP is an economic indicator and its difference between two buses across a transmission line provides the measure of the degree of congestion, therefore, it is efficiently and reliably used in deregulated electricity market for conges- tion management. This paper utilizes the difference of LMP across a transmission line to categorize various congestion zones in the system. After the identification of congestion zones, distributed generation is optimally placed in most congestion sensitive zones using LMP difference in order to manage congestion. The performance of the proposed methodology has been tested on the IEEE 14-bus system and IEEE 57-bus system. 展开更多
关键词 locational marginal price (LMP) distributed generation pool market deregulated electricity market congestion management
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Optimal Unit Commitment with Renewable Energy in Regulated and Deregulated Systems
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作者 Adel A. Abou El-Ela Sohir M. Allam Amira S. Doso 《Energy and Power Engineering》 CAS 2022年第8期420-442,共23页
In this paper, the impact of the wind power generation system on the total cost and profit of the system is studied by using the proposed procedure of binary Sine Cosine (BSC) optimization algorithm with optimal prior... In this paper, the impact of the wind power generation system on the total cost and profit of the system is studied by using the proposed procedure of binary Sine Cosine (BSC) optimization algorithm with optimal priority list (OPL) algorithm. As well, investigate the advantages of system transformation from a regulated system to a deregulated system and the difference in the objective functions of the two systems. The suggested procedure is carried out in two parallel algorithms;The goal of the first algorithm is to reduce the space of searching by using OPL, while the second algorithm adjusts BSC to get the optimal economic dispatch with minimum operation cost of the unit commitment (UCP) problem in the regulated system. But, in the deregulated system, the second algorithm adopts the BSC technique to find the optimal solution to the profit-based unit commitment problem (PBUCP), through the fast of researching the BSC technique. The proposed procedure is applied to IEEE 10-unit test system integrated with the wind generator system. While the second is an actual system in the Egyptian site at Hurghada. The results of this algorithm are compared with previous literature to illustrate the efficiency and capability of this algorithm. Based on the results obtained in the regulated system, the suggested procedure gives better results than the algorithm in previous literature, saves computational efforts, and increases the efficiency of the output power of each unit in the system and lowers the price of kWh. Besides, in the deregulated system the profit is high and the system is more reliable. 展开更多
关键词 Profit Based Unit Commitment Problem Binary Sine Cosine Optimal Priority List Regulated and deregulated System
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Analytical Framework for Market-oriented DSR Flexibility Integration and Management 被引量:1
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作者 Shi You Junjie Hu +1 位作者 Kai Heussen Chunyu Zhang 《Energy and Power Engineering》 2013年第4期1367-1371,共5页
Integration and management of the flexibility of Demand Side Resources (DSR) in today’s energy systems plays a significant role in building up a sustainable society. However, the challenges of understanding, predicat... Integration and management of the flexibility of Demand Side Resources (DSR) in today’s energy systems plays a significant role in building up a sustainable society. However, the challenges of understanding, predicating and handling the uncertainties associated this subject to a great extent hamper its development. In this paper, an analytical framework based on a multi-portfolio setup in presence of a deregulated power market is proposed to address such challenges by adopting the thinking in modern portfolio theory (MPT). A Numerical example that targets on analyzing the risk and return for various flexibility pricing strategies are presented to illustrate some features of the framework. 展开更多
关键词 ANALYTICAL FRAMEWORK Distributed Energy Resources Flexiblity deregulated Power Market Morden PORTFOLIO Theory Risk and RETURN
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Load frequency control in deregulated power system with wind integrated system using fuzzy controller 被引量:1
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作者 Yajvender Pal VERMA Ashwani KUMAR 《Frontiers in Energy》 SCIE CSCD 2013年第2期245-254,共10页
This paper presents the analysis of load frequency control (LFC) of a deregulated two-area hydro-thermal power system using fuzzy logic controller, with doubly fed induction generators (DFIGs) integrated into both... This paper presents the analysis of load frequency control (LFC) of a deregulated two-area hydro-thermal power system using fuzzy logic controller, with doubly fed induction generators (DFIGs) integrated into both the control areas. The deregulation of power sector has led to the formation of new companies for generation, transmission and distribution of power. The conventional two-area power system is modified to study the effects of the bilateral contracts of companies on the system dynamics. Deregulation creates highly competitive and distributed control environment, and the LFC becomes even more challenging when wind generators are also integrated into the system. The overall inertia of the system reduces, as the wind unit does not provide inertia and isolates from the grid during disturbances. The DFIGs integrated provide inertial support to the system through modified inertial control scheme, and arrests the initial fall in frequency after disturbance. The inertial control responds to frequency deviations, which takes out the kinetic energy of the wind turbine for improving the frequency response of the system. To enhance the participation of the doubly fed induction generator (DFIG) in the frequency control, optimal values of the speed control parameters of the DFIG-based wind turbine have been obtained using integral square error (ISE) technique. The dynamics of the system have been obtained for a small load perturbation, and for contract violation using fuzzy controller. 展开更多
关键词 frequency regulation fuzzy controller deregulated power system doubly fed induction generator(DFIG) bilateral contract
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Carbon Tax and Renewable Energy Diffusion in the Deregulated Texas Electricity Market: An Agent-Based Analysis
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作者 Joshua D. Halperin I-Tsung Tsai 《Journal of Power and Energy Engineering》 2015年第4期384-393,共10页
In the United States, emission regulations are enacted at a state level;individual states are allowed to define what methods they will use to mitigate their carbon emissions. The consequence of this is especially inte... In the United States, emission regulations are enacted at a state level;individual states are allowed to define what methods they will use to mitigate their carbon emissions. The consequence of this is especially interesting in the state of Texas where new legislation has created a “deregulated” electricity market in which end-users are capable of choosing their electricity provider and subsequently the type of electricity they wish to consume (generated by fossil fuels or renewable sources). In this paper we analyze the effects of carbon tax on the development of renewable generation capacity at the utility level while taking into account expected adoption of rooftop PV systems by individual consumers using agent based modeling techniques. Monte Carlo simulations show carbon abatement trends and proffer updated renewable portfolio standards at various levels of likelihood. 展开更多
关键词 deregulated ELECTRICITY MARKET Rebewable ADOPTION AGENT-BASED Modeling MONTE Carlo Simulation
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Hybrid Neuro Fuzzy Controller for Automatic Generation Control of Multi Area Deregulated Power System
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作者 Baghya Shree Solaiappan Nagappan Kamaraj 《Circuits and Systems》 2016年第4期292-306,共15页
This paper is intended in investigating the Automatic Generation Control (AGC) problem of a deregulated power system using Adaptive Neuro Fuzzy controller. Here, three area control structure of Hydro-Thermal generatio... This paper is intended in investigating the Automatic Generation Control (AGC) problem of a deregulated power system using Adaptive Neuro Fuzzy controller. Here, three area control structure of Hydro-Thermal generation has been considered for different contracted scenarios under diverse operating conditions with non-linearities such as Generation Rate Constraint (GRC) and Backlash. In each control area, the effects of the feasible contracts are treated as a set of new input signals in a modified traditional dynamical model. The key benefit of this strategy is its high insensitivity to large load changes and disturbances in the presence of plant parameter discrepancy and system nonlinearities. This newly developed scheme leads to a flexible controller with a simple structure that is easy to realize and consequently it can be constructive for the real world power system. The results of the proposed controller are evaluated with the Hybrid Particle Swarm Optimisation (HCPSO), Real Coded Genetic Algorithm (RCGA) and Artificial Neural Network (ANN) controllers to illustrate its robustness. 展开更多
关键词 AGC ANFIS ANN deregulated Power System HCPSO RCGA
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A Novel Approach for a Two Area Load Frequency Control in a Competitive Electricity Market Adopting Unscheduled Interchange Price
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作者 Murugesan Bhavani Kamatchi Selvi Ravi Durga 《Circuits and Systems》 2016年第7期1155-1166,共11页
This paper proposes a novel price based load frequency control scheme for a two area system, using an Unscheduled Interchange (UI) price signal, which is ideal and suitable for electricity market. The Government of In... This paper proposes a novel price based load frequency control scheme for a two area system, using an Unscheduled Interchange (UI) price signal, which is ideal and suitable for electricity market. The Government of India has introduced Availability Based Tariff (ABT) structure with an intention of ensuring grid security and to regulate grid indiscipline through Central Electricity Regulatory Commission Regulation. After the introduction of this regulation, the over or under injection by the generating companies (GENCOs) during off peak or peak hours are demoralized and the frequency is maintained at the nominal value. In this paper, the GENCOs instead of reacting to this price signal manually, an automated mode of frequency control is deployed in each area using UI price signal to achieve fast response to load change. The Distribution Company (DISCO) Participation Matrix (DPM) has also been employed in this work to relate the scenario under deregulation of electricity market. The proposed scheme has been verified for different cases by simulating it on a two area system, each having four GENCOs and one DISCO in MATLAB/SIMULINK environment. From the results, it is clearly observed that if the proposed method is employed by all GENCOs, it will certainly enhance the control of system frequency and at the same time throw down the UI liability of market participants. It also ensures that the GENCOs and DISCOs strictly adhere to the bilateral contract following the DISCO participation matrix. 展开更多
关键词 deregulated Electricity Market Bilateral Contract Unscheduled Interchange CONTRACT
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Review of Methods to Calculate Congestion Cost Allocation in Deregulated Electricity Market
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作者 Jiawei Zhao Jianfeng Lu Kwok Lun Lo 《World Journal of Engineering and Technology》 2016年第3期16-26,共11页
With maturing deregulated environment for electricity market, cost of transmission congestion becomes a major issue for power system operation. Uniform Marginal Price and Locational Marginal Price (LMP) are the two pr... With maturing deregulated environment for electricity market, cost of transmission congestion becomes a major issue for power system operation. Uniform Marginal Price and Locational Marginal Price (LMP) are the two practical pricing schemes on energy pricing and congestion cost allocation, which are based on different mechanisms. In this paper, these two pricing schemes are introduced in detail respectively. Also, the modified IEEE-14-bus system is used as a test system to calculate the allocated congestion cost by using these two pricing schemes. 展开更多
关键词 deregulated Electricity Market Transmission Congestion Management Congestion Cost Allocation Uniform Marginal Price and Locational Marginal Price
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Assessment of Available Transfer Capability for Congestion Management in Restructured Electrical Power Network for Competent Operation
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作者 U. L. Makwana S. K. Joshi Mehul D. Solanki 《Journal of Power and Energy Engineering》 2014年第4期395-402,共8页
Congestion is the prime cause of problems, due to open access of power system. The AC Power Transmission Congestion Distribution factor (PTCDF) is suitable for computing change in any line quantity for a change in MW ... Congestion is the prime cause of problems, due to open access of power system. The AC Power Transmission Congestion Distribution factor (PTCDF) is suitable for computing change in any line quantity for a change in MW bilateral transaction. The proposed PTCDF method is more accurate as compared to the DC power distribution factor. With PTCDF ATC can be calculated. After calculating ATC it is possible to know the valid multiple transaction on power system. With the help of ATC calculations congestion problem can be solved in restructured electrical power network. The paper presents the method for calculating ATC using PTCDF. 展开更多
关键词 ATC (Available Transfer Capability) deregulated Market OASIS ISO Open Access Generating COMPANIES (GENCOS) TRANSMISSION COMPANIES (TRANSCOS) DISTRIBUTION COMPANIES (DISCOS) PTCDF (Real TRANSMISSION CONGESTION DISTRIBUTION Factor) QTCDF (Reactive TRANSMISSION CONGESTION DISTRIBUTION Factor)
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p-SAGE:基因集合的参数统计分析方法(英文) 被引量:2
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作者 黄波 李文婷 +2 位作者 李雯 夏雪峰 孙之荣 《生物化学与生物物理进展》 SCIE CAS CSCD 北大核心 2009年第11期1415-1422,共8页
肿瘤的发生与发展通常是由重要的细胞通路表达水平的反常导致的.尽管目前已经有很多工作利用基因表达谱数据以及一些其他的先验知识来寻找那些与肿瘤相关的基因集合,但还是没有一个恰当的基因集合的统计学方法.大多数研究都是直接将单... 肿瘤的发生与发展通常是由重要的细胞通路表达水平的反常导致的.尽管目前已经有很多工作利用基因表达谱数据以及一些其他的先验知识来寻找那些与肿瘤相关的基因集合,但还是没有一个恰当的基因集合的统计学方法.大多数研究都是直接将单基因的检验方法直接应用到基因集合上来.提出了基因集合的参数统计分析方法(p-SAGE),这个方法应用到大脑肿瘤的实验中,识别了许多显著的基因集合.一些新发现的基因集合是与信号转导和免疫相关的.这个简便有效的方法可以得出有生物学意义的结果. 展开更多
关键词 参数统计分析方法 基因集合 反常基因
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A novel statistically tracked particle swarm optimization method for automatic generation control 被引量:1
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作者 Cheshta JAIN H.K.VERMA L.D.ARYA 《Journal of Modern Power Systems and Clean Energy》 SCIE EI 2014年第4期396-410,共15页
Particle swarm optimization(PSO)is one of the popular stochastic optimization based on swarm intelligence algorithm.This simple and promising algorithm has applications in many research fields.In PSO,each particle can... Particle swarm optimization(PSO)is one of the popular stochastic optimization based on swarm intelligence algorithm.This simple and promising algorithm has applications in many research fields.In PSO,each particle can adjust its‘flying’according to its own flying experience and its companions’flying experience.This paper proposes a new PSO variant,called the statistically tracked PSO,which uses group statistical characteristics to update the velocity of the particle after certain iterations,thus avoiding localminima and helping particles to explore global optimum with an improved convergence.The performance of the proposed algorithm is tested on a deregulated automatic generation control problem in power systems and encouraging results are obtained. 展开更多
关键词 Statistically tracked particle swarm optimization(STPSO) Group statistical characteristics deregulated automatic generation control(AGC)
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China's Oil Market to be Deregulated Slowly
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《China Oil & Gas》 CAS 1999年第4期218-220,共3页
Nowadaysitismoreandmoredifficulttofindarapidmoney-makingmarket,butChina's1.2-billion-peoplemarketisnodoubtanattractivecaketoforeigninvestorstointroducecapitalandtechnology.Manymajorinternationaloilfirmshavemadeana... Nowadaysitismoreandmoredifficulttofindarapidmoney-makingmarket,butChina's1.2-billion-peoplemarketisnodoubtanattractivecaketoforeigninvestorstointroducecapitalandtechnology.Manymajorinternationaloilfirmshavemadeanattemptforthecountry'soilmarket.Inther... 展开更多
关键词 BP China’s Oil Market to be deregulated Slowly
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West-East Gas Pipeline Project Fully Deregulated for Foreign Cooperation
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《China Oil & Gas》 CAS 2000年第3期4-6,共3页
关键词 PROJECT West-East Gas Pipeline Project Fully deregulated for Foreign Cooperation
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现代电网稳定理论和分析技术的研究方向 被引量:29
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作者 薛禹胜 《电力系统自动化》 EI CSCD 北大核心 2000年第7期1-6,共6页
从环保、电力市场和跨大区联网的角度出发 ,讨论了现代电网对稳定分析理论和技术的挑战。从系统规划、运行规划、在线运行和稳定控制等应用方面探讨了新一代稳定分析软件应该具有的功能 ,指出新一代稳定分析算法的基本特征之一是为同步... 从环保、电力市场和跨大区联网的角度出发 ,讨论了现代电网对稳定分析理论和技术的挑战。从系统规划、运行规划、在线运行和稳定控制等应用方面探讨了新一代稳定分析软件应该具有的功能 ,指出新一代稳定分析算法的基本特征之一是为同步、电压、频率稳定性提供严格的量化指标 ,强调引入概率观点和风险观点 ,以及将稳定分析功能与电价优化功能相集成的重要意义。要实现电力系统灾变防治的目标 ,必须在非线性稳定理论上有所突破。文中提出了失稳轨迹在趋于无界的形态上的敏感依赖性 (称之为无界混沌 )以及到达不返回点之前的动态过程的敏感依赖性 (称之为预无界混沌 )的新概念。揭示这些现象的本质 ,有助于深入地理解失稳模式变化的机理 。 展开更多
关键词 灾变防治 稳定理论 稳定分析 电网 电力系统
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电力市场环境下虚拟电厂两阶段能量经济优化调度 被引量:23
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作者 赵力航 常伟光 +2 位作者 杨敏 杨强 秦刚华 《中国电力》 CSCD 北大核心 2022年第10期14-22,共9页
随着分布式可再生能源在电网中的渗透率不断增加,虚拟电厂作为一种高效管理分布式可再生能源的技术已经引起国内外学者的广泛关注。提出一种非管制电力市场环境下的虚拟电厂两阶段能量经济优化调度方法,该方法将虚拟电厂的调度分为日前... 随着分布式可再生能源在电网中的渗透率不断增加,虚拟电厂作为一种高效管理分布式可再生能源的技术已经引起国内外学者的广泛关注。提出一种非管制电力市场环境下的虚拟电厂两阶段能量经济优化调度方法,该方法将虚拟电厂的调度分为日前和日内2个阶段。在日前阶段,基于预测信息制定次日的最优调度计划并与日前电力市场签订协议;在日内阶段,以日前计划为参考,采用模型预测控制策略调整日内的运行计划,以消除由于预测误差导致的净负荷波动,同时尽可能减少来自日内平衡市场的罚款,降低总体运行成本。所提出的模型均使用商业求解器Gurobi进行求解。仿真数值结果表明:所提出的算法通过日前计划和日内调控的手段提高了可再生能源设备的利用率,具备一定的经济性和实用性,为虚拟电厂的经济调度提供了新的思路和途径。 展开更多
关键词 虚拟电厂 非管制电力市场 日前计划 日内调控 模型预测控制
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电力市场竞价算法研究综述 被引量:7
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作者 余志文 郭志忠 +1 位作者 于尔铿 赵惠 《华北电力大学学报(自然科学版)》 CAS 北大核心 2001年第1期20-23,共4页
电力市场的开放给电力工业注入了新的活力,同时也给电力系统的研究引入了一系列新的课题,竞价算法是最重要的一个方面。分析了竞价算法中各类约束的特点,重点是时间约束和网络约束,并对处理这些约束的数学方法进行了探讨。最后提出... 电力市场的开放给电力工业注入了新的活力,同时也给电力系统的研究引入了一系列新的课题,竞价算法是最重要的一个方面。分析了竞价算法中各类约束的特点,重点是时间约束和网络约束,并对处理这些约束的数学方法进行了探讨。最后提出了竞价算法迫切需要解决的问题:有效地处理网络安全约束以及网络安全约束和价格的关系。 展开更多
关键词 电力市场 电力工业 竞价算法 市场化经营
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基于Stackelberg博弈的售电侧放开环境下电能质量定价方法 被引量:5
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作者 董立志 刘皓明 +2 位作者 周辉 殷文倩 侯云鹤 《电力需求侧管理》 2020年第2期28-33,共6页
售电侧放开后,用户拥有自主选择权,电能的商品属性凸显,电能质量决定电价,因此对于售电公司而言,如何根据电能质量合理确定销售电价,是亟待解决的问题。提出一种基于Stackelberg博弈的电能质量定价方法,考虑多个售电公司与多个用户进行... 售电侧放开后,用户拥有自主选择权,电能的商品属性凸显,电能质量决定电价,因此对于售电公司而言,如何根据电能质量合理确定销售电价,是亟待解决的问题。提出一种基于Stackelberg博弈的电能质量定价方法,考虑多个售电公司与多个用户进行博弈,引入消费者参考价格和“自我选择约束”概念建立用户选择模型,在此基础上分别建立用户收益和售电公司收益优化模型,通过Stackelberg博弈求解模型寻找最优电价。算例分析表明基于Stackelberg博弈的电能定价方法能够合理确定销售电价,满足用户电能质量和收益要求的同时保证了售电公司的盈利水平。 展开更多
关键词 定价方法 电能质量 STACKELBERG博弈 售电侧放开 售电公司
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售电侧放开环境下供电服务质量动态综合评估方法 被引量:4
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作者 顾国华 曹依丹 +1 位作者 王通 金龙 《电力需求侧管理》 2020年第3期69-74,共6页
在售电侧放开环境下,对供电服务质量的提升已成为售电公司在新一轮电改中立足并发展的关键。构建了售电侧放开下的供电服务质量评价指标体系,提出一种基于双激励控制线的售电公司供电服务质量动态综合评估方法,能够基于传统通过赋权对... 在售电侧放开环境下,对供电服务质量的提升已成为售电公司在新一轮电改中立足并发展的关键。构建了售电侧放开下的供电服务质量评价指标体系,提出一种基于双激励控制线的售电公司供电服务质量动态综合评估方法,能够基于传统通过赋权对供电服务质量进行静态评估的方法,考虑供电服务质量在时序上的变化,引入"奖惩机制",对供电服务质量进行动态评价。建模分析与仿真结果显示,所构建的指标体系与评估方法能够提升售电公司的市场自我状态感知能力,帮助售电公司提升综合供电服务质量水平。 展开更多
关键词 供电服务质量 动态评估 双激励控制线 售电侧放开 售电公司
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售电侧放开环境下电能质量管理现状分析及建议 被引量:3
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作者 朱明晞 李燕雪 胡斌 《电力需求侧管理》 2021年第3期96-100,共5页
售电侧放开给电能质量的管理带来巨大影响。不同类型的售电公司参与市场,造成电能质量管理的困难。首先讨论了售电侧放开给电能质量管理带来的影响,对比分析了国内外电力企业的电能质量管理差异,然后从指标管理层面、售电业务发展趋势... 售电侧放开给电能质量的管理带来巨大影响。不同类型的售电公司参与市场,造成电能质量管理的困难。首先讨论了售电侧放开给电能质量管理带来的影响,对比分析了国内外电力企业的电能质量管理差异,然后从指标管理层面、售电业务发展趋势和电价管理层面对中国售电侧放开后的电能质量管理提出建议,为中国在电力市场环境下管理电能质量提供参考。 展开更多
关键词 电能质量 售电侧放开 指标管理 按质论价
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