Abstract:In the scenario of high proportion of renewable energy access, how to improve the flexibility of the power system has become a focus. Electrochemical energy storage can improve the flexible regulation ability of new power systems, but its technical characteristics are different from conventional market players, so it is necessary to design the corresponding market participation mechanism. Therefore, according to the relationship between depths of charge and discharge, charging and discharging ratio of energy storage and aging cost, a price difference bidding mode suitable for energy storage participation is proposed. In this bidding mode, the energy storage can declare the cost under different operation states and different depths of discharge, so as to release the deep charging and discharging capacity of the energy storage. Considering the coupling relationship between energy storage frequency regulation capacity and state of charge, the market clearing model is established for the coupling of day-ahead energy market and frequency regulation market. The case results show that the proposed mechanism can fully reflect the market value of energy storage, promote the optimal allocation of energy storage resources, and improve the market revenue of energy storage.

Abstract:China is comprehensively carrying out the construction of the electricity spot market, and the spot pilot areas have built relatively complete spot market operation support systems based on current market rules and the current status of the power system, supporting the effective operation of the current electricity spot market. With the gradual increase of the proportion of renewable energy in the construction of new power systems and the implementation of the “carbon emission peak and carbon neutrality” national strategy, the existing operation technology support system will not be able to meet the needs of future market development. On the basis of summarizing the technical practice of electricity spot market in China, the changes in the characteristics of the electricity spot market and the technical challenges it faces are analyzed, and the key technologies in the future are discussed in the aspects of multi-agent modeling and access, market clearing algorithm, market risk analysis, trusted trading environment, market simulation, etc. Some technologies have been preliminarily applied.

Abstract:In order to solve the problems of the regional electricity spot market to coordinate the priority plan of trans-provincial sending and receiving power and the trans-provincial medium- and long-term trading system, and to make sure that the clearing results of the regional electircity spot market can truly reflect the pre-authorized trans-provincial transmission price and the network loss rate, a clearing model for the regional electricity spot market with the deviation correction of network losses in the trans-provincial transmission grid is proposed. Firstly, taking the China southern regional electricity spot market as an example, the trans-provincial sending and receiving power trading entities and trading system are analyzed. Secondly, a deviation correction method of network losses considering both trading components and physical power flow is proposed, and based on this method, a clearing model for the regional electricity spot market with coupling of physical power flow and trading components is constructed. Finally, a 9-bus system and the China southern power grid simulation system are adopted to conduct simulation and verification. The simulation results show that the proposed deviation correction method and the clearing model for the regional electricity spot market can ensure that the trans-provincial transmission price and network loss rate can be reflected in the clearing price on the premise that the system safety operation constraints are satisfied. The priority plan of the trans-provincial sending and receiving power and the trans-provincial medium- and long-term trading system are effectively coordinated.

Abstract:The resource endowment and energy demand in China are in reverse distribution, and promoting the optimal allocation of renewable energy resources in a wider range is an inherent requirement for the construction of new power system of China. The trans-provincial/trans-regional transmission price is an important part of the trans-provincial/trans-regional electricity transaction price, and the rationality of its pricing mechanism will not only affect the reasonable recovery of the investment costs of power transmission projects, but also affect the efficiency of the electricity market competition, even the optimal allocation of resources in a wider range. To this end, based on combining the current situation of trans-provincial/trans-regional and transnational/interstate transmission projects in typical electricity markets in China, Europe, and the United States, the historical evolution and development situation of transnational/interstate and inter-market transmission pricing mechanisms in typical international electricity markets are sorted out, and the key factors influencing the transnational/interstate and inter-market transmission pricing are explored. Combined with the historical development of the transmission pricing mechanism of the trans-provincial/trans-regional dedicated projects in China, the problems that the current transmission pricing mechanism for trans-provincial/trans-regional dedicated projects will face in the background of new power system and the construction of the national unified electricity market system are analyzed, and its enlightenment and the future development direction for the transmission pricing of trans-provincial/trans-regional dedicated projects in China are put forward.

Abstract:The construction of the new power system in China is facing the challenge of a shortage of flexible resources, and it is urgent to exert the adjustment ability of load side. As the mutual interaction between the power grid and load becomes more frequent, more load aggregators participate in market transactions by integrating jurisdictional flexible resources, resulting in the break of the market equilibrium dominated by the power generation side in the past. In order to study the game strategy of multi-agent load aggregators, a bi-level bidding model of load aggregators under energy-reserve electricity market is constructed, and multiple scenarios are introduced to describe the influence of bidding uncertainty of non-decision makers on the market equilibrium. The multiple bi-level models are transformed into an equilibrium problem with equilibrium constraints (EPEC) model by strong stationary method (SSM), and linearization methods such as big-M method and binary expansion approach are used for linearization. Results of the case validate the validity and effectiveness of the model and solving algorithm, demonstrating that the EPEC model based optimal bidding strategy of load aggregators is more in line with the actual market rules, which is helpful to optimize the load curve of the system and alleviate the tension between the supply and demand of flexible resources.

Abstract:Constructing an electricity market system for new power system is not only an inevitable requirement of energy and electricity transition but also an important route to achieving the goal of “carbon emission peak and carbon neutrality”. Based on the comprehensive analysis of the changes and challenges brought to power systems by the structural changes of the new power system, a multi-dimensional collaborative electricity market system for the new power system is built from the goals, time, space, values, and entities. Focusing on the five key issues including the multi-goal collaboration of safe supply guarantee, low-carbon transition and economy, the multi-time collaboration of medium- and long-term, spot, and real-time operation, the multi-spatial collaboration of multi-layer national unified electricity market, the multi-value collaboration of security, green and economy, and the multi-entity collaboration with the rapid development of emerging market entities, the concept and core mechanism for the multi-dimensional collaborative market design are proposed. Finally, the implementation route and suggestions for constructing a national unified electricity market are given.

Abstract:The design and construction of the national unified electricity market system focuses on the variety of electric energy, and auxiliary services, as an important variety to ensure the safety of the power system, also need to adapt to the main energy market and carry out the top-level design from the perspective of the national auxiliary service market system. The paper analyzes the overall situation of China’s regional and provincial auxiliary service market mechanisms. Under the basic framework of the national unified electricity market, based on the analysis of the basic development form of the electricity energy market, from the dimensions of market hierarchy, market variety, and market cycle, the connection relationship between levels and varieties is sorted out, and the overall framework and construction development path of the national auxiliary service market that adapts to different market development stages are proposed.

Abstract:New requirements for the electricity market mechanism are proposed due to the rapid development of renewable energy. China has established two-stage inter- and intra-provincial electricity spot markets for promoting the renewable energy accommodation and reliable power supply. However, with the increasing scale and proportion of inter-provincial transactions, the power supply connection between each province becomes closer, which exacerbates the risk transmission between each intra-provincial electricity spot market. Firstly, the risk transmission characteristics between intra-provincial electricity spot markets based on the current linking-up mechanism between inter- and intra-provincial electricity spot markets is analyzed, and the concept of spillover risk value to quantitatively evaluate the risk transmission in the inter- and intra-provincial electricity spot markets is introduced. Secondly, a coordinated clearing model for the two-stage inter- and intra-provincial electricity spot markets under spillover risk constraints is built based on the two-stage stochastic optimization theory to suppress the risk transmission in the two-stage inter- and intra-provincial electricity spot markets. Furthermore, considering the privacy protection needs brought about by different market operating institutions, a solving method for the coordinated clearing model of the two-stage inter- and intra-provincial electricity spot markets based on the alternating direction method of multipliers (ADMM) is established. Finally, the case analysis verifies that the proposed market clearing model and method are effective in suppressing the risk transmission in the two-stage inter- and intra-provincial electricity spot markets.

Abstract:In order to support the efficient and stable operation of inter-provincial electricity spot trading, it is urgent to develop operation technologies that adapt to the characteristics of inter-provincial electricity spot trading, and achieve the efficient and coordinated operation of various markets. First, the paper introduces the background and trading mechanism of inter-provincial electricity spot trading, analyzes the technical challenges faced by market operation, constructs an operation functional framework for inter-provincial electricity spot trading, and designs a data flow based on wide-area distributed parallel technology. On this basis, multiple operation technologies are proposed, including the wide-area collaborative interaction technology, the inter-provincial electricity spot trading clearing technology that supports global bidirectional trading, the multi-stage security verification technology based on model reconstruction, and the full-process auxiliary decision-making analysis technology based on the module flexible linkage. Finally, the engineering application of the described operation technologies is introduced, and the operation technologies that need further breakthroughs are prospected combined with the evolution direction of the future electricity spot market.

Abstract:Driven by the goal of “carbon emission peak and carbon neutrality” and affected by the geographical distribution and randomness of renewable energy, the importance of mutual support between regional power and flexibility using cross-regional trading as a medium is highlighted. At present, China is in the critical stage of building a unified national electricity market system, and an effective market mechanism is needed to manage large-scale inter-provincial electricity spot trading. Based on the above background, an inter-provincial electricity spot trading approach which does not depend on cross-regional bidders is designed. First, a market clearing model based on bidding zones is proposed and the zonal marginal pricing method is used to calculate the settlement price for each zone. Then,transmission tariffs for each transaction between regions are calculated according to power flow contributions based on the equivalent bilateral matching method. Finally, numerical examples verify the effectiveness of the proposed method. Compared with existing methods, the proposed method accomplishes inter-provincial electricity trading without relying on cross-regional bidders. It utilizes the capacity of transmission lines efficiently and protects the privacy of internal network information in each area during the market clearing process.

Abstract:Actively promoting the construction of green electricity market is an effective way to promote the green and low-carbon transformation of energy consumption and realize the goal of carbon emission peak and carbon neutrality. China has already started the construction of green electricity market, which is currently in the period of rapid development. There is an urgent need to study the related key issues to provide the support for the construction of green electricity market. This paper analyzes the connotation of green power and green electricity market, and studies the practice of green electricity market in foreign countries from the aspects of policy design, operation mechanism, application scenarios, and support technology with the United States and Europe as typical cases, and puts forward relevant inspiration. On this basis, combined with the progress of green electricity market construction in China, this paper discusses the key issues of green electricity market construction in China under the goals of carbon emission peak and carbon neutrality, and puts forward the key mechanism design and technical difficulties that need to be solved in the green electricity market construction of China from four aspects of top-level design, key mechanisms, connecting mechanisms, and support technologies.