1. General bidding mode of provincial power market

The transformation of electric power industry from comprehensive monopoly mode to competitive market mode is an arduous and complicated task, which needs to be completed seriously. The experience of international power market reform tells us that the reform of breaking monopoly in power industry must choose a suitable model according to the characteristics of domestic power development, formulate a clear plan through research and demonstration, and implement it step by step with the support of laws and regulations.

China's electricity market reform should also learn from this principle. The ultimate goal of market-oriented reform of electric power industry is to maximize the use of market means to improve the production efficiency of electric power industry, reduce the cost of electric power production and supply, and realize the optimal allocation of resources.

As far as the current development level of electric power industry and related social and economic relations are concerned, this goal must be gradually realized. By gradually introducing competition in different links of power production, fully considering the formed power supply characteristics and power grid structure, combining with the future power grid development pattern, constructing market structure at different levels, selecting and formulating appropriate market operation mechanism, and establishing and perfecting market supervision system, the power marketization reform will develop steadily.

In the reform of provincial power market, it is safe to implement limited competition on the basis of the existing system in the near future, and it is a perfect power market in the long run.

The electricity market with limited competition is a combination of planning and market, and only the power generation market is opened. Generally speaking, opening the power generation market is not only conducive to introducing competition in the power generation market, but also easier to manage. It is a relatively stable practice and will not make major changes to the existing system of power companies.

A perfect power market is a pure market model. The power generation market and the user market are open at the same time, realizing the two-way choice of supply and demand, especially expanding the choice of users. In this mode, the electricity price plays the role of adjustment fulcrum, and the power producers and users in the market can consciously abide by the operation rules.

1) Power Market with Generation Side Competition-Mode Ⅰ

This model can be regarded as the most initial stage of commercial operation by using market mechanism. When the technical equipment, personnel quality and operation management have not reached a certain advanced level, this model can be adopted to improve the comprehensive level of the power industry as soon as possible and ensure the development of social electricity consumption and national economy.

This model can be divided into the following two stages:

A. the stage of power market with limited competition on the generation side

At this stage, in the provincial administrative area, the power generation terminal has become an independent power generation company, and the provincial power company has the power transmission and distribution network with a voltage level of 220 kV and below, and the asset management right of all substation equipment and dispatching centers in the province. ?

The basic characteristics of this stage are: the power grid is separated from the power plant, the existing power generation enterprises and large-capacity local power generation enterprises are gradually transformed into independent power generation companies, the provincial and regional networks have the conditions to compete openly, the electricity consumption is settled daily, and the market regulations and technical support system are initially established. At this stage, the limited bidding under the guaranteed base power is realized, and the grid-connected units are guaranteed to complete the base power. The electricity in the basic electricity is settled according to the approved electricity price, and the remaining electricity is competitive.

At this stage, historical reasons are considered instead of the inherent characteristics of the unit itself, such as the differences between new and old power plants, investment sources and channels, repayment conditions and investment return methods.

At this stage, the provincial power company will be responsible for the planning, construction, development and operation of the provincial power grid (transmission and distribution), and carry out electricity sales and transmission business under the supervision of the government industry supervision department. The upstream of the company is connected with grid-connected independent power generation companies and network-level companies operating inter-provincial power and power exchange, and the downstream directly faces users. The sales target of the provincial electric power company is power consumers. The company should conduct various market surveys and long-,medium-,short-and real-time load forecasting, and pay the electricity purchase fee to the upstream link to purchase electricity. Because the provincial power company is in a monopoly position, its electricity selling price will be controlled by the government's industry supervision department, but the electricity selling price should reasonably include the related expenses of transmission and distribution to ensure the reasonable return of the company's assets and its own development needs.

B. the stage of electricity market in which the generation side is completely competitive

At this stage, all power plants within the jurisdiction of the province have become independent power generation companies. Independent power generation companies openly and completely compete to access the Internet, and quote for half an hour; Form a relatively complete market regulations, rules and technical support system. After a period of time, it is inevitable to transition to this stage in the power market with limited competition on the generation side. At this stage, it is necessary to solve the problem of electricity purchase market of a provincial power company. After the separation of power grid and power plants, regardless of the differences in nature, scale and equity composition of power generation companies, in order to ensure the commercial operation order of provincial companies, any power plant in the province must participate in the power generation side power market of provincial companies, cancel the base power, and the power generation companies implement complete competition to generate electricity. All participants in market economy activities are equal.

2) Open transmission network, multi-buyer mode-mode Ⅱ.

The goal of mode 2 is to form a completely open and competitive power market. On the basis of the first model, the competition in the power generation market will be further improved, and at the same time, the competition in the distribution market will be carried out in a timely manner according to the reform process of the national power system, so that the electricity price level will be significantly reduced. Characterized in that:

& gt On the basis of Mode I, the power generation side will implement complete bidding, open the distribution market in an orderly manner, and establish an independent city power supply company.

If the national policy allows, some large users can purchase electricity directly from independent power generation companies in a certain region and transmit it through transmission and distribution networks. Users and independent power generation companies pay related fees to transmission and distribution networks. When conditions are ripe, large users can be allowed to choose power supply companies across regions, including purchasing electricity directly from independent power generation companies or trading with other power supply companies.

This is a model adopted under the condition of perfect market mechanism. In this mode, the provincial power company has completely transformed into a power grid company, monopolizing the transmission link. Power supply enterprises and large users directly purchase electricity from power production enterprises. Power grid companies are responsible for internet power exchange, safe operation of power grid and operation of power market, undertake the transportation function of power and collect network fees. The collection of internet access fees is subject to the supervision of the relevant public utility management institutions of the state.

Before the power grid enterprise is transformed into a complete transmission company and collects the network fee, it can make a transition for a certain period of time, so that a part of the electricity is purchased by the power grid enterprise from the power generation enterprise and then resold to the power supply enterprise and large users, and the other part is directly purchased by the power supply enterprise and large users from the power generation enterprise, and the power grid enterprise collects the network fee.

3) retail competition mode-mode Ⅲ

The retailer sends a notice to the user, and the user selects the retailer according to the electricity price and service quality, and signs a power supply contract with the retailer; At present, there is complete competition not only in power generation but also in retail.

2. Hydrothermal power bidding method:

1) All thermal power plants participate in the futures market.

2) Thermal power plants that can be directly dispatched by the provincial dispatching center participate in recent electricity market transactions.

3) Thermal power plants with high automation level (AGC units and units with strong load tracking ability) participate in the transaction between real-time market and auxiliary service market.

4) The futures market adopts the settlement rules of marginal electricity price, and forms trading electricity quantity and trading electricity price through multiple bidding competitions. Quote the futures market for more than one year according to the annual power generation; For the monthly futures market, the price is quoted according to the monthly power generation increment (relative to the electricity traded in the futures market in the previous year).

5) In the day-ahead market, the trading volume in the futures market is decomposed into days, and the daily volume of futures is decomposed into each scheduling cycle according to the normalized unit value of the system load curve, thus forming the futures volume of each cycle. The difference between the load curve and the futures electricity quantity is the bidding space of the power market in recent days. In the recent market, according to the market supply and demand situation, the corresponding power purchase price formation mechanism should be adopted to prevent excessive marginal electricity price from making power plants obtain excess profits.

6) In the real-time market, only units with strong load tracking ability and dedicated data channels participate in the real-time market competition. The bidding space of real-time market is the difference between the ultra-short-term load forecast value and the planned power generation of pre-purchased electricity. According to the market supply and demand situation, the corresponding electricity purchase price formation mechanism is adopted to organize bidding.

7) In the auxiliary service market, units with auxiliary service capabilities can participate in bidding. In the FM auxiliary service market, the trading center announces the required FM capacity, and the units are quoted separately according to the capacity and electricity price. The trading center will organize bidding according to the sum of capacity electricity price and electricity price and the settlement rules of controlled marginal electricity price, but the settlement price of FM service shall not be lower than the marginal settlement price of units in the active market, so as to encourage units to participate in FM service. In the hot standby auxiliary service market, the units are quoted separately by capacity and electricity, but the ranking index of bidding is: the product of electricity quotation and system failure probability, plus the unit capacity quotation. According to the market supply and demand situation, the corresponding electricity purchase price formation mechanism is adopted to organize bidding.

8) Regional bidding mode of small thermal power plants: Because there are a large number of small thermal power plants and there is no special communication channel, these power plants only participate in the futures bidding market of the current year and the current month. The daily output curve will be determined according to the unit value of the power consumption and load curve decomposed into one day. It is worth emphasizing that: for qualified provincial markets, small thermal power bidding should be conducted in the provincial futures market, rather than organizing bidding in different regions, so as to achieve a wider range of optimal allocation of resources; For provincial markets that do not have certain conditions, small thermal power will bid for the Internet by region when the total amount of small thermal power is certain.

9) Bidding mode of heating units: In the heating season, such units do not participate in bidding according to the principle of "determining electricity by heat", and generate electricity on the grid according to the fixed output curve, and the electricity price is settled according to the price approved by the Price Bureau. Other seasons will participate in the bidding as other units.

10) hydropower bidding mode: for provinces and cities with few hydropower plants, it is suggested that hydropower should not participate in bidding for online access and be leased and operated by power grid companies. The economic principle of hydropower dispatching is to reduce the marginal power generation price of thermal power system in the day-ahead market, real-time market and auxiliary service market by using limited hydropower generation.

3. Unit grouping (class) bidding online mode

In the early stage of the power market, considering the current situation of China's power industry, especially the cost difference between power plants caused by historical reasons rather than the inherent characteristics of the unit itself, such as the difference between new and old power plants, investment sources and channels, loan repayment conditions, investment return methods, etc. All units in the provincial power grid can be divided into several types according to the cost difference, and according to certain market operation rules, the mode of bidding for power grid access by groups (categories) is adopted.

4. Bidding mode among power generation groups

In the early stage of the power market, considering the current situation of China's power industry, especially the cost difference between power plants caused by historical reasons rather than the inherent characteristics of the unit itself, such as the difference between new and old power plants, investment sources and channels, loan repayment conditions, investment return methods, etc. , all the units in the provincial power grid can be shared equally according to the cost difference to form several (preferably around 10) generating sets (each generating set should be included).

5. The role of provincial power grid trading center in regional power market.

According to the present situation that China's economy is dominated by provinces, the price-based agency mechanism should be adopted as the bidding model to develop inter-provincial electricity market. In this mode, the power grid trading centers in each province are not only single buyers, but also agents for power producers in this province to sell electricity on a large scale. The provincial power grid trading center will organize a large-scale bidding for the surplus power of power plants in the province. Therefore, the provincial power grid trading center will declare the quotation curve of buying and selling electricity to the large region. Therefore, it is necessary to formulate the trading rules of provincial power grid trading centers as agents.

Second, the regional electricity market bidding model

There are three basic operation modes of regional electricity market: bilateral transaction mode and single buyer mode; Power broker model.

1) bilateral trading mode

The initial market members are provincial power grid companies. The parties to the market negotiate and sign the contract separately; Or, the regional market operation organization provides a place for information exchange (including BBS).

Both parties to the transaction are members of each market and have nothing to do with regional market operators. Usually, there will be a breach of contract clause in the contract. If the contract is not fulfilled, the breaching party will compensate the other party for its losses. The model is suitable for forward contracts and futures electricity markets.

In order to promote the bilateral contract market, regional system operators should establish a bulletin board system (BBS), and provinces can buy and sell electricity and capacity according to the bulletin. This bulletin board contributes to effective information exchange among provinces.

In this mode, the regional dispatching center does not participate in bilateral transactions, but it must ensure the security and reliability of the system during the transaction. In general, system operators don't have to care about the contract price, but only care about the transaction and trading time that the system needs to provide. There should be a series of rules that clearly define the responsibilities of various institutions in the bilateral market. Sometimes, due to transmission congestion or sudden failure of power generation and transmission facilities, the contract transaction volume has to be reduced or interrupted. In these cases, the regional dispatching center must sort all kinds of transactions, determine their relative importance, and notify all market participants to reduce or cancel transactions. Usually, uncertain transactions are reduced first, then short-term transactions are reduced, and finally long-term transactions are reduced.

2) Single buyer mode

The model requires provinces to allocate a part of the load electricity to the regional power trading center to form the bidding electricity of regional power supply plants. All market members participate in the quotation, and a single buyer in the region arranges the trading plan according to the principle of giving priority to buying low-priced electricity.

The characteristics of this model are: the purchase and sale of electricity must be carried out in the regional joint venture center, which is responsible for the balance of trading volume in the region. Market transactions are not completely "free" but regulated. The core of the model is a bidding, tendering and bid evaluation process and an optimization decision-making module. Power generation companies in power-deficient provinces report their acceptable minimum sales price to the regional trading center, while power generation companies in power-rich provinces report their acceptable maximum purchase price to the regional trading center. The regional trading center conducts price matching and gives the unified price of the transaction as the settlement basis.

The basis of implementing this model is that provincial power companies sign multilateral contracts with regional trading centers in advance, and independent institutions supervise regional trading centers.

3) Power broker model

According to the present situation that China's economy is dominated by provinces, the price-based agency mechanism should be adopted as the bidding model to develop inter-provincial electricity market.

In this mode, the trading centers in each province are not only single buyers, but also agents for large-scale electricity sales by power producers in this province. The regional trading center is a broker who informs all parties of the prices of potential buyers and sellers every hour. This model is mainly used in time-sharing electricity market.

Each market member declares its electricity quotation, and the broker system matches the potential transaction according to the high-low matching method, determines the transaction price and checks the security of the system. The specific steps are as follows:

Step 1: Collect quotation information. Collect quotations from market members. The electricity selling quotation represents the price of extra electricity provided by a province, and the electricity buying quotation represents a province to reduce the avoidable cost of production. All quotations must be submitted to the regional broker one hour before the transaction.

Step 2: Price sequencing. After receiving all the quotations, the regional brokers rank, with the quotations for selling electricity ranked from low to high, and the prices for purchasing electricity ranked from high to low.

Step 3: Quote matching. Once the quotations of buyers and sellers are collected, regional brokers will sort and compare the provinces with the lowest selling price with the provinces with the highest buying price. Then, the second lowest selling price is compared with the second highest buying price, and this process continues until there is no quotation to compare or the lowest selling price is higher than the highest buying price. This process is called high-low comparison method. Thereby determining both parties to the transaction. Not all economic transactions after high-low pairing are feasible from a technical point of view. Lack of transmission lines, transmission congestion or stability restrictions set by system operators will make spot trading impossible. When the transaction cannot be concluded, the regional broker will compare the remaining highest purchase price with the lowest selling price.

Step 4: Determine the transaction price. For both parties to the transaction, the transaction price is the average of the selling price and the buying price of both parties. In order to recover the transmission investment with the proceeds, this method of evenly distributing profits can be modified, and the buyer and the seller each pay part of the proceeds to the transmission company.

Step 5: Notify all parties to the transaction. After discovering the transaction and determining the transaction price, the intermediary will inform all parties of the relevant information within a certain period of time before the transaction.

Step 6: Implement the transaction. The provinces confirm their participation in the transaction and conduct the transaction. Confirm at least ten minutes before the transaction.

We believe that the future regional electricity market may adopt the third mode. This method is conducive to the safe operation of the power grid and suitable for different bidding modes and market rules in different provinces (this is because the situation in different provinces is different)

There is a view that power trading should be carried out in a wide range, without the need for provincial trading centers, but replaced by regional power trading centers; In the case of a single buyer, this means that the electricity prices of all provinces converge to a large extent. For economically developed provinces with high power generation cost, the electricity price drops, while for economically underdeveloped provinces with low power generation cost, the electricity price rises, which may contradict the provincial economy in China.

Coordination of "futures trading market, spot trading market, real-time trading market and auxiliary service trading market" in power market.

Usually, according to the length of lead time, futures trading market, day-ahead trading market and real-time trading market are set up in the power market, and hot standby and FM are divided into auxiliary service markets as service commodities. However, the importance of coordination between different markets has not been recognized by people. In fact, is it reasonable to allocate the annual futures electricity to every month and all futures electricity to every day? Is it related to whether the electricity price is stable in the future? Is power production stable? Can the daily trading plan provide more security adequacy and bidding space for real-time market? Based on the above reasons, the coordination methods of multi-level market are put forward, including:

1) Coordination between annual and monthly markets;

2) Coordination between monthly market and recent market;

3) Coordination between day-ahead market and real-time trading market;

4) Coordination of auxiliary service market, day-ahead market and real-time trading market.

1. Coordination between annual and monthly markets

In order to ensure the good connection between the annual futures contract and the monthly trading plan, the distribution of the annual futures contract in the monthly market should be considered in the monthly trading plan. In the transaction management system, the connotation of annual and monthly contract coordination is: according to the load curve of the whole year and the arrangement of unit maintenance, make the ratio of annual futures electricity to the total load electricity of the current month as equal as possible, so as to ensure the electricity price in different months as stable as possible and the balance between supply and demand.

The key to the coordination of monthly and annual plans is to adjust the annual contracted electricity distribution in the remaining months according to the operation results of the current market after one month's operation. The detailed algorithm is described as follows:

1) Forecast the monthly load demand for the remaining months in the future;

2) Calculate the ratio of the annual futures electricity quantity to the total monthly electricity quantity;

3) Select the month in which the annual futures electricity accounts for the smallest proportion of the total monthly electricity, and increase the annual futures electricity of that month by a certain step;

4) Check whether the annual futures electricity is fully distributed? If yes, the calculation is finished; Otherwise, go to [2].

2. Coordination between the monthly futures market and the recent electricity market.

As the contract electricity quantity and contract electricity price of each trading entity have been determined in the futures trading decision-making in 2000 and 2000, as far as the allocation decision of daily contract electricity quantity is concerned, it is not how to further reduce the cost of purchasing electricity, but to pursue the unity of futures electricity quantity in space and time and the stability of spot market price. The even distribution of futures electricity in time is beneficial to the continuous start-up of units and avoids frequent start-up of units; The uniform distribution in space will make the power flow evenly distributed, and ensure that enough transmission capacity margin is reserved for the spot market, which is not only conducive to the safe operation of the power grid, but also prepares more bidding space for the spot market. The stability of spot market price is reflected in the trading day with heavy load, and the distribution of futures electricity is also large. Only in this way can we avoid the spot price fluctuation caused by the unbalanced bidding space in the spot market every day. Based on the above reasons, we suggest adding the daily contract power allocation decision module to the technical support system of the power market.

3. Coordination between day-ahead market and real-time market

In order to ensure the safe and reliable operation of the system, it is necessary to coordinate the relationship between the day-ahead market and the real-time market. Between these two markets, we should not only consider the economy and security of the same level market, but also reserve enough dispatching control space for the lower level market. In this way, on the basis of considering the main uncertain factors, the day-ahead trading plan and real-time scheduling process can be naturally connected, smoothly transitioned and carried out in an orderly manner, thus comprehensively improving economic and social benefits.

In order to coordinate the day-ahead market and real-time market, the scheduling fluency and scheduling fluency indexes of trading plan are introduced.

Scheduling fluency is the performance of the size of scheduling and control space when the trading plan adapts to uncertain factors. Scheduling fluency is an index to measure the scheduling fluency of trading plans.

For simplicity, the dispatching fluency index adopts the following evaluation criteria:

The characteristic of scheduling fluency is the maximum increase of the total system load that the trading plan can bear when the load growth mode of each node is fixed and the constraints of power generation and transmission are considered. On the basis of a given trading plan, if the total load increases, the load increment is distributed to each node in a fixed proportion; If the maximum load growth that the system can bear is obtained, the fluency index is expressed by the ratio with the total load of the system, as shown in the following formula.

=/* 100%

The fluency index under this standard is similar to the traditional load reserve rate in form, but it is superior to the traditional concept of load reserve rate by considering the distribution characteristics of total reserve in a specific sense. The greater the fluency index, the smoother the transition between multi-level markets.

When evaluating the range of load growth that the system can bear, the load growth mode of each node is specified. This assumption is representative, because for a specific system, the load growth pattern has a relatively fixed law. For simplicity, the load growth pattern can be made proportional to the load on each node.

4. The relationship between auxiliary services and real-time trading market and spot market

The auxiliary service market will provide the deployment scope and standby scope of the unit for the spot market and the real-time market. Real-time and spot markets will make optimization decisions of pre-scheduling plan and real-time plan according to the specified constraints within this range. In other words, when making pre-scheduling and real-time power purchase plans, priority should be given to ensuring the implementation of the auxiliary service market plan.