Table of Content

05 November 2019, Volume 52 Issue 11

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Economic Dispatch of Microgrid in Southwest China Based on Two-Stage Robust Optimization

WEI Mingkui, ZHOU Quan, ZHOU Hong, CAI Shaorong, JIANG Li, LU Liang, LIANG Wenju, SHEN Li, LI Qi

2019, 52(11):  2-8,18.  DOI: 10.11930/j.issn.1004-9649.201907049

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According to the characteristics of abundant renewable energy reserves in southwest China, considering the influence of the uncertainty of renewable energy output and load on the operation scheduling of micro grid, this paper establishes a two-stage robust optimization economic dispatching model to obtain the economic optimal solution of the system under extreme operating scenarios. The model considers system power balance, output power constraints, demand response load constraints, and interaction constraints between microgrid and distribution network. The uncertainty in microgrid is dealt with through uncertain adjustment parameters, and the conservatism of the model is adjusted. Then Benders decomposition algorithm is used to solve the main problem and sub-problem of the model, and duality theory is used to decouple the inner layer model. Finally, the results verify the effectiveness of the proposed model, and provide a reference for the scheduling strategy after the microgrid is connected to the southwest power grid.

Day-Ahead Market Clearing Model of Integrated Energy System for Promoting Renewable Energy Consumption

ZHOU Lin, FU Xueqian, LIU Shuo, LI Guodong, ZENG Dan

2019, 52(11):  9-18.  DOI: 10.11930/j.issn.1004-9649.201907092

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Renewable energy, such as wind and solar energy, has significant clean characteristics, which can reduce the carbon emissions of the energy industry. However, the problem of abandoning wind and solar energy is still very serious in China. In order to promote the consumption capacity of wind and solar energy, this paper makes a deep research on the mechanism of clean energy absorption under the background of national unified electricity market. This paper analyses the engineering problems of the renewable energy consumption in China, and establishes a simulation model of the integrated energy system including combined heat and power system, natural gas boiler and wind and solar energy. Aiming at maximizing social welfare, a day-ahead market clearing model, which can promote the new energy consumption, is put forward for the integrated energy system. The clearing model considers the power demand side management, which makes the clearing model has significant characteristics of modern power system. The proposed day-ahead market clearing model has been simulated and validated in Matlab software. The simulation results verify the positive effect of the proposed clearing model on the renewable energy consumption.

A Day-Ahead Nash Bargaining Method for Economic Dispatch of the Multi-operator Micro-grid

WU Ming, KOU Lingfeng, ZHANG Jin, HU Cungang

2019, 52(11):  19-27,117.  DOI: 10.11930/j.issn.1004-9649.201905076

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In the deregulated electricity market environment, the power trading can be carried out among the operators in the micro-grids. In this paper, we take the cost of individual transactions between operators in a micro-grid and power distribution network as the disagreement point of bargaining, and propose a day-ahead economic dispatching Nash bargaining method for multi-operators in micro-grids based on Nash cooperative game theory. This method can minimize the cost of micro-grid systems while each operator obtains Pareto optimal cost. The Nash bargaining model based on this method is a non-convex and non-linear model, which is not easy to solve directly. This paper decomposes the Nash bargaining model into two convex sub-models and uses ADMM algorithm to solve them sequentially in order to protect the privacy of operators. The simulation gives the cost comparison of each operation agent in the micro-grids before and after the bargaining, and further analyses the Nash bargaining strategy among multi-operators in the island mode.

Research on Competition Strategy of Integrated Energy Service Provider under the Pool-based Market Mechanism

GUO Zuogang, YU Lei, HU Yang, ZHOU Changcheng, LEI Jinyong, HE Shuai, LIU Nian

2019, 52(11):  28-34.  DOI: 10.11930/j.issn.1004-9649.201903025

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With the strengthening of multi-energy coupling and the advancement of energy reform, the integrated energy market has been gradually established, and severe energy price fluctuations in the integrated energy spot market have brought great risks to integrated energy service providers (IESP). Aiming at this problem, a cooperative game based risk aversion strategy of IESP's in spot market is proposed in this paper. Firstly, a risk assessment model of spot market transaction based on Value at Risk (VaR) is established. Secondly, a cooperative alliance between IESP is established in order to reduce the overall alliance's spot market trading risks. Finally, the Shapley value method is used to decide the allocation of risk among the members of the alliance, and a trading rule for the risk allocation result is proposed. Simulation results show that the IESP can effectively reduce the risks of participating in the spot market by forming alliances. Meanwhile, the risk allocation method based on Shapley value could ensure the fairness of allocation and the stability of the alliance, and the effectiveness and feasibility of the model is verified.

A Reserve Decision Model for High-Proportional Renew Energy Integrated Power Grid Based on Deep Peak-Shaving and Virtual Storage

XUE Chen, REN Jing, ZHANG Xiaodong, CUI Wei, LIU Youbo

2019, 52(11):  35-43.  DOI: 10.11930/j.issn.1004-9649.201907134

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With the capacity of renew energy continued to grow rapidly in the northwest China, the contradiction between the consumption demand of renew energy and the characteristics of its inverse peak shaving has become the severe challenges. On the other hand, the gradual marketization of power operation also provides a new way for large-scale consumption of renew energy. Based on this, a market decision model of adjustment standby is proposed based on deep peak-shaving and virtual storage in new energy high-permeability grid. First, this paper proposes a peaking reserve model of new energy with uncertainty participation which consider new energy output volatility. Based on the price sensitivity of user-side resources, an alternate model based on the "charge and discharge" capability of "virtual energy storage" is constructed. Secondly, based on deep peak-shaving technology of thermal power units, the compensation mechanism of different peak regulation depth is determined and the standby model for deep peak shaving of thermal power unit is used. Lastly, taking the new energy consumption as the core, the system peaking and standby cost is the minimum, and the standby decision model of virtual energy storage and thermal power deep participation is built. The simulation of the example showed that the proposed decision model is effective to ensure the capacity of adjustment standby.

Establishment and Simulation of Prosumers Transaction Model in P2P Mode

HU Yang, ZHOU Changcheng, MA Xiyuan, YUAN Zhiyong, LEI Jinyong, TIAN Bing, SHAN Junjia, HU Junjie

2019, 52(11):  44-50.  DOI: 10.11930/j.issn.1004-9649.201907108

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With the liberalization of the electricity selling side in the new electricity reform environment, more and more prosumers are willing to participate in the electricity market to reduce their own electricity consumption expenditure. How to develop the electricity purchasing and selling model for prosumers under the P2P trading mode has become an urgent problem. Firstly, the paper proposes the prosumer resource models for photovoltaic (PV), micro-gas turbine and fixed load resource clusters, respectively. Secondly, lagrange duality decomposition principle and sub-gradient method are adopted to develop the electricity purchase and sale plan for prosumers based on the P2P market transaction mode with the objective of minimizing the operating cost of prosumers, by which the P2P power sharing between prosumers can be realized. Finally, an example is given to verify the rationality and effectiveness of the proposed strategy.

Optimal Allocation of Distributed Generation in Distribution System Considering Multi-type Demand Response Resources

ZHAO Nan, WANG Beibei

2019, 52(11):  51-59,67.  DOI: 10.11930/j.issn.1004-9649.201805112

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In recent years, the distributed generation (DG) and demand response (DR) resources have made up an increasing portion in the operation of active distribution network. In order to fully utilize the resources of distribution system, a study is made in this paper on integrated planning of intermittent distributed generation and multi-type demand response resources. To obtain the optimal allocation scheme of intermittent DG and DR, a chance-constraint programming-based bi-level optimal model is established according to their output characteristics. A series of simulations are made on the IEEE 34-node distribution system to understand the influence of DR's interaction on DG allocation. Simulation results illustrate that DR resources can be dispatched to improve the wind curtailment, load curtailment and voltage exceeding problem, consequently enhancing the access capability of DGs. In different application scenarios such as large difference between peak and valley loads, voltage exceeding and power line congestion, the allocations of DR are also different. The model proposed in this paper lies a foundation for large-scale DR resources participating in distribution system planning.

Remote Sensing Discrimination Algorithm for Transmission Line Forest Fire Based on Fuzzy Comprehensive Evaluation Method

TANG Bo, LI Yaowei, YE Li, HUANG Li, YUAN Fating, CHEN Hao, FENG Peng

2019, 52(11):  60-67.  DOI: 10.11930/j.issn.1004-9649.201811108

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The traditional remote sensing discrimination algorithm for transmission line forest fires usually uses the brightness temperature threshold method to directly perform the fire point discrimination, which makes it difficult to accurately set the threshold value and frequently lead to false discrimination or omissions. In order to realize the accurate remote sensing discrimination of transmission line forest fires, the idea of second discrimination of hot spots is proposed based on the traditional fire point discrimination algorithm, that is, after determining the possible hotspots according to the threshold value of the brightness temperature, the fuzzy comprehensive evaluation is carried out for the hotspots to determine the exact point of fire. According to the research of the time and spatial distribution of forest fires in Guangdong Province, six hazard factors causing the occurrence of forest fires are determined, and a fuzzy comprehensive evaluation method is proposed to realize the accurate discrimination of transmission line forest fires. Firstly, the fire risk decision-making set and threshold are determined according to the fire risk evaluation levels. Then, the factor set is established as input with the six hazard factors, and the membership function is constructed and the weight vector is set. The confidence of the hotspot is output according to the principle of maximum membership degrees, and compared with the threshold to determine the authenticity of the fire point. The model is verified using the forest fire database in Guangdong Province from 2005 to 2016 and by a case study of Guangdong Power Grid in 2017. The results show that the model has higher accuracy than traditional algorithms and meets the prevention and control requirements for transmission line forest fires.

Planning Method of Multi-energy Complementary Micro Energy Grid on User Side

LI Dezhi, GONG Taorong

2019, 52(11):  68-76.  DOI: 10.11930/j.issn.1004-9649.201809126

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Multi-energy complementary micro-energy grid is an effective way to improve energy efficiency and reduce power supply costs through integrating multi-energy carriers.Against numerous energy converters of various types and storage devices with different characteristics, the selection of the type and capacity of the devices, and the connection and management of the selected devices are the key challenging problems for designing the optimal configurations of new micro energy grids. This paper proposes a new planning method of multi-energy complementary micro energy grid on user side, which can give full play to the advantages of multi-energy complementary and obtain the optimal configuration. The optimal planning model is a mixed-integer linear programming with the objective to minimize the overall cost. The effectiveness and superiority of the optimal planning model proposed in this paper are demonstrated by comparing three different energy system schemes with an energy interconnection demonstration project in Haidian District of Beijing.

Multi-source Data Fusion Method for Distribution Network Based on Spatiotemporal Grid under Extreme Disasters

CHEN Bin, NI Ming, ZHOU Xia, YU Chen, WU Han, YANG Zhou, LIN Husheng

2019, 52(11):  77-84.  DOI: 10.11930/j.issn.1004-9649.201812115

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Extreme disasters will have a certain impact on the distribution network, and even disrupt the safe and stable operation of the power grid. A large number of data about distribution network equipment and operation are generated during the disaster events, which are large in information contents and high in volatility. In order to timely grasp the damage information of distribution network equipment under extreme disaster events and effectively assist the post-disaster repairing work of the distribution network, a spatiotemporal grid based distribution network multi-source data fusion method is proposed. Firstly, according to the spatiotemporal grid division method, the area where the distribution network is located is partitioned in time and space, and a spatiotemporal grid coding database of the distribution network is established. Then, the characteristic analysis of the multi-source data of the distribution network under extreme disaster events is carried out to extract key time features and spatial features. By calculating the correlation degree of spatiotemporal features, the spatiotemporal grid and the distribution network multi-source data are associated and stored in the spatiotemporal grid coding database. Further, the grid view of the distribution network damage is constructed according to the fused multi-source data of the distribution network. The results of the case study show that the proposed method is effective and reasonable.

New Algorithm of Forest Fire Spread Simulation Based on Cellular Automata and Power Line Fault Probability Calculation

LIU Hui, LI Pengfei, LIN Jikeng, WANG Zhongyue

2019, 52(11):  85-93.  DOI: 10.11930/j.issn.1004-9649.201801158

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Forest fire has been one of the important reasons for the transmission line outrage. Current cellular automata model for the simulating forest fire spread doesn't consider different spread scenarios of neighbor cells, resulting in low simulation accuracy and low accuracy of failure probability of power lines under mountain fire disaster condition. In this paper, A new forest fire spread simulation algorithm is proposed, considering overlapping area of adjacent neighbor cells spreading area and adjacent neighbor cell spreading area. Based on the area, the new method of calculating the power line failure probability is further presented. The new algorithm takes into account overlapping area in different spread scenarios and puts forward the corresponding calculating method. Based on this, an improved conversion rule of cell states and corresponding new forest fire simulation algorithm are constructed, obtaining more accurate forest fire spread front and area. Furthermore, a new method for calculating the line fault probability is proposed, which can obtain the line fault probability caused by the more accurately. The example proves the effectiveness of the proposed method.

Analysis and Application of New Lightning Protection Equipment of Distribution Lines in Shaanxi Province

JU Zeli, LV Xinliang, PU Lu, ZHAO Xuefeng, HOU Zhe, LU Zejun, WU Jun

2019, 52(11):  94-99.  DOI: 10.11930/j.issn.1004-9649.201809010

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Based on the operation situation of the lightning arresters commonly used in Shaanxi Province, a lightning arrester with multi-short-gaps is developed, which has excellent ability in extinguishing arc. It is determined through testing that the lightning arrester can act reliably with parameters of 26 in series number, 8 mm in electrode diameter, 1 mm in electrode gap clearance and 45 mm in main gap clearance; and the power frequency wet withstand voltage, the 50% lightning impulse withstand voltage, the volt-second characteristics of lightning impulse and the current cut-down ability all meet the requirements of standard. The newly developed lightning arrester operates well in typical lines in Shaanxi Province with good lightning protection performance.

Novel Flexible Excitation System Based on Multilevel Topology Technology

WU Kuayu, ZHANG Jiancheng, WU Long, HAN Bing, FANG Le, LU Cencen, XIONG Hongtao

2019, 52(11):  100-106.  DOI: 10.11930/j.issn.1004-9649.201809077

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Based on the development trend of the next generation power system, a novel flexible excitation system is designed based on three-level voltage source converter, and a matching five-level DC chopping circuit is proposed. An analysis is made of the controlling mode and performance of two DC chopping circuits with excitation current 6-IGBT or 3-IGBT. A simulation model of flexible excitation system is built based on PSCAD. The feasibility of the flexible excitation system with proposed five-level chopping topology and the control performance advantage over conventional self-shunt excitation are analyzed and verified.

Regional Photovoltaic Consumption Control Strategy Based on Non-MPPT Algorithm

NIU Geng, KOU Lingfeng, HOU Xiaogang, QU Xiaoyun, XIE Hui, GAO Bo

2019, 52(11):  107-117.  DOI: 10.11930/j.issn.1004-9649.201905042

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This paper proposes a Non-MPPT algorithm suitable for regional rooftop photovoltaic power generation system to solve the problem of excess capacity of PV power generation system, based on the environmental adaptive algorithm of two-stage photovoltaic power generation system and the distributed structure of photovoltaic array. In the normal conditions, the shading PV module can realize the decentralized control based on the distributed pre-optimizer of PV module. And through the PV module output voltage and current random variables, the PV battery environmental correction parameters are derived, and the maximum power voltage of the regional PV module is corrected in real time, so that the maximum power voltage follows the external environment changes in real time, and combined with the conductance increment method to achieve PV array global maximum power tracking in different environments. If the output of photovoltaic power supply of the power grid is excessive, the regional roof PV will be managed according to its actual power output. Through the power distribution amount of the regional power grid, the output voltage of the rooftop PV array can be derived. And the derived voltage will be introduced into the front stage Boost circuit of the photovoltaic power generation system. Then, by modifying the duty ratio of the boost circuit, the output power of the photovoltaic power generation system can quickly follow the demand instruction of the main network, so as to realize the consumption of excess output of rooftop PV in the region. Finally, a two-stage three-phase photovoltaic grid-connected system is built by Matlab/Simulation to verify the effectiveness of the algorithm in the applications of power system.

Diagnostic Analysis of Daily Coal Consumption Rate in Coal Fired Unit Based on Data Reconciliation

LIU Fuguo, ZHANG Xuhui, WU Ju, CUI Fuxing

2019, 52(11):  118-124.  DOI: 10.11930/j.issn.1004-9649.201904001

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Due to the difficulties to measure the coal consumption and calorific value, using positive balance method is not an accurate way to determine the net coal consumption rate for the coal fired units. In this work, the diagnostic analysis method for coal consumption rate by taking advantage of positive balance procedures in power plants is proposed. Integrated with the designed performance of boiler and steam turbine, the thermodynamic test data through the indirect balance method and the accuracy class of instruments, this method is employed on the basis of the maximum likelihood principle to reconcile the daily measurement data in coal consumption rate test. The practice on a 350 MW supercritical unit shows that through the application of the reconciliation model the gross measurement errors can be detected from the test data and then reconciled to reasonable values. After the reconciliation, coal consumption rate values are highly accurate and stable, which decrease as the unit load increases. Besides, even though as much as 52% of the measurement data have been reconciled, the average measurement value of the coal consumption rate will not be altered by this model within the entire period, because of the positive and negative deviations of the reconciled data cancelling out each other over a longer period.

Multi-sensor Fault Detection for Natural Gas Combined Cycle Power Plants Based on Multiple Robust Input Training Neural Network Models

HUANG Zheng, WANG Hongxing, YU Haiquan, LI Dou, SI Fengqi

2019, 52(11):  125-133.  DOI: 10.11930/j.issn.1004-9649.201812068

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In order to enhance the accuracy and reliability of multiple sensor measurements in natural gas combined cycle (NGCC) power plants, a multi-sensor fault detection method based on multi-model robust input training neural network is proposed in this paper, in which multiple robust input training neural network (RITNN) models are built and prioritized for the purpose of sensor faults reconstruction and monitoring. The relationship between the models are set in terms of serial or parallel connections. The influence of numerous failure data with significant errors can be effectively inhibited by virtue of reliable sensor data calculated from cooperative multi-model, such that the accuracy and reliability of fault detection is greatly improved. In addition, the process for sensor fault detection is presented to establish a complete fault dectection system. The proposed method was evaluated in a 200 MW NGCC power plant, where the multi-sensor fault detection was conducted and the results were compared with those from single RITNN model and single input training neural network (ITNN) model detection.The proposed method demonstrated higher accuracy in multiple sensor failure cases than the single RITNN model or the single ITNN model.

Analysis on Energy Saving of 350 MW Supercritical Turbine with Low-Grade Energy Heating Technology

ZHOU Guoqiang, SUN Xianming

2019, 52(11):  134-137,184.  DOI: 10.11930/j.issn.1004-9649.201907091

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The extraction of steam for heat supply in traditional combined heat and power generation plant is found with several issues such as low heating capacity, large power loss, high comprehensive energy consumption and low exergy efficiency. In this paper, the low-grade energy heating technology on the basis of heat classifications for wet cooling units is utilized in the energy saving retrofit project of a 350 MW supercritical cogeneration unit. The operation results indicate that after the retrofit, the heating capacity and the power generation output of the unit increased by 35% and over 8% respectively under the same main steam mass flow. In addition, as the annual heating capacity is expanded by 1.886 5 million GJ, the power generation output has increased by 83.9 million kW·h with year-over-year revenue growth about 93.416 million RMB during the heat supply period. That means after the completion of the retrofit project 126.9 thousand tons of coal equivalent have been saved for the social society and the CO₂ emission has been reduced by 330 thousand tons.

An Intelligent Weed Recognition Method Based on Optical Patrol Image

YUE Guoliang, LU Yanqiao, CHANG Hao, SUN Cuiying

2019, 52(11):  138-144,174.  DOI: 10.11930/j.issn.1004-9649.201902152

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Power inspection is currently carried out mainly by drones. The weeds around the power equipment may cause potential safety hazards when the patrol images acquired by drones are used for patrol inspection, it is therefore necessary to recognize the weeds in the image. In this paper, a method for intelligent recognition of weeds is proposed for power patrol inspection based on optical patrol images. Based on the feature of weeds in the optical images, and combined with the convolutional neural network method, the problem of weed recognition near the power equipment in optical patrol images is solved. By amplifying and preprocessing the sample data of the optical patrol images, and introducing the region proposal network, the image features of the fixed number of candidate frames are extracted from the images. Then the network is connected to the improved image classification network to obtain a final convolutional neural network model. The experiments show that the accuracy rate can reach 97.98%, and the average time taken for detecting a 600×600 image is around 0.256 seconds, which meets the requirements of efficient recognition while ensuring accuracy.

Data Collaborative Detection Scheme of Electric Metering System Based on Edge Computing

QIAN Bin, CAI Ziwen, XIAO Yong, YANG Jinfeng, DONG Xingyin, GU Ke

2019, 52(11):  145-152.  DOI: 10.11930/j.issn.1004-9649.201904049

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False data injection attacks are aimed at destroying the integrity and availability of power data in electric metering system. The false data detection scheme is of great significance to the secure and stable operation of smart grid. In order to address many security problems caused by false data in smart grid, this paper proposes a collaborative detection model of false data injection attacks based on edge computing, which improves the network structures of traditional metering system and provides the capability of global monitoring and detection function for false data by edge servers in smart grid. The scheme not only proposes some rules of detection for false data injection in electric metering system, but also constructs the reputation mechanism for data collectors. The simulation experiments have proved the validity of our proposed scheme.

A Detection Platform of Attitude Sensor System Used for Double Reconfirmation Technology of Disconnecting Switch's Opening and Closing Position

DU Fei, WANG Guangzhen, ZHANG Hejun, GONG Yanpeng, GE Dong

2019, 52(11):  153-158.  DOI: 10.11930/j.issn.1004-9649.201905002

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To support the performance testing of the attitude sensor system used for double reconfirmation of the opening and closing position of substation disconnecting switches, a detection platform is built based on single-axis turntable and motor control technology. By using the current loop, velocity loop, position loop and feedback grating it has, the platform achieves the precision movement under different acceleration and rotation rates. Then, the testing method and testing indicators used for attitude sensor system are studied. The test results indicate that the detection platform can satisfy the requirement of measurement accuracy and repeatability testing of the attitude sensor system. The testing effect of the three-axis turntable is achieved by a single axis turntable, which reduces the testing cost without compromising the detection accuracy.

Design of Asymmetric Regulatory Framework for Electricity Distribution Companies

ZHANG Xiang, HONG Xiaofeng, HUANG Guori, HAN Shiqi

2019, 52(11):  159-166.  DOI: 10.11930/j.issn.1004-9649.201907101

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The supervision of China's electricity retail market is still in an incomplete and defective stage. With the rapid liberalization of electricity retail market and the orderly liberalization of incremental distribution business to social capital, the new electricity distribution companies not only operate the distribution business in the incremental distribution area, but also compete with independent companies in the retail market. It has formed a vertically integrated monopolistic market position, and it is urgent to conduct asymmetric regulation on the distribution companies and their associated retail companies to facilitate the survival and development of independent electricity retail companies.This paper analyzes the business characteristics and changes of business sector of distribution companies which are different from traditional power supply enterprises. Combining with specific business analysis, it discusses six kinds of unfair competition behaviors, such as resource subsidy, price discrimination and non-price discrimination which may occur in vertical monopoly of the distribution companies. Subsequently, based on the asymmetric regulation theories, the paper studies the asymmetric regulatory framework and contents of distribution companies and their related electricity sales business from five aspects:finance, tariff, power supply services, infrastructure and business isolation.

Determining Heat Storage Tank Capacities in Consideration of the Economic Operation of Virtual Power Plant

ZHOU Renjun, WU Haoran, FENG Jian, WANG Yu, WANG Yangzhi, WANG Long

2019, 52(11):  167-174.  DOI: 10.11930/j.issn.1004-9649.201812054

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In the novel thermoelectric system, a heat storage device can effectively decouple "heat-set power" constraints and resolve the curtailment of wind power. In view of the optimal allocation of thermal storage tank capacity, the investment and maintenance costs of the thermal storage tank were added to the virtual power plant operation model consisting of wind turbine, thermoelectricity, thermal storage tank and carbon capture, then converted into daily depreciation and daily maintenance costs. The objective function is defined as the minimization of total operating cost of the virtual power plant subject to the thermal-electric coupling constraints of the cogeneration unit as well as the ramping up constraints of thermal storage tanks and carbon capture units. The simulation results show that with the optimized capacity of the regenerator tank the unit operation is more economical than those with the traditional given regenerative tank capacity, and more efficient regarding the heat storage effect. The optimal capacity of the regenerator tank depends not only on the economic efficiency of the virtual power plant, but also on the constraints such as carbon capture, wind power consumption, etc. in the virtual power plant. Without carbon capture requirement, or with the higher wind power consumption requirements, the optimum capacity of the regenerator tank could be even higher.

A Method for Benefit Evaluation and Investment Optimization Considering Functional Differences in Transmission and Transformation Projects

WANG Zhicai, CAI Ye, TAN Yudong, XIE Xintao, JIANG Zhengwei, LIN Minjuan

2019, 52(11):  175-184.  DOI: 10.11930/j.issn.1004-9649.201902001

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With the deepening of reform in power system, the investment of transmission network construction in China tends to transit from extensive growth to high-quality development. Therefore, for the purpose of refining the investment approach of the power grid, it is of great significance to propose an investment benefit evaluation and optimization method by taking account of the functional differences of transmission and transformation projects. In order to accurately evaluate the benefits of transmission and transformation projects with different functions, firstly, an evaluation index system of transmission and transformation projects including the functional differences specified was established considering the benefits of technology, economy and society, according to the functional classification of the projects, and based on the main benefits of different functional projects in terms of the functionalities provided. Secondly, the graph theory and optimization theory was introduced to calculate the weights of indexes, and corresponding method was put forward to distinguish the difference of project benefits and reduce the subjective error in the existing method. Finally, an investment allocation and project optimization model classified by project function was established based on the project evaluation results in combination with the present status and scale of the power grid as well as the investment constraints. Taking the 220 kV transmission and transmission projects in Hunan as the example, it is verified that the proposed method can effectively quantify the investment benefit of different functional transmission and transformation projects, and is helpful to improve the investment efficiency of the power grid.