Method for clearing cross-zone power reserve market considering transmission line reserve capacity

Abstract

The present application relates to a kind of cross-regional power reserve market clearing method considering transmission line reserve capacity, comprising the following steps: S1, power spot market is pre-clearing according to spot market clearing model, obtains the node price of each time and the output curve of each unit;S2, according to the power spot market clearing result, the opportunity cost of unit reserve market is calculated;S3, unit reports quantity bidding in spot-reserve joint clearing market;S4, according to the unit quantity bidding data and the electric energy demand of power market, reserve demand, establish spot-reserve joint clearing model, carry out spot-reserve market joint optimization clearing.The present application can optimize the reserve capacity provided by transmission line when carrying out cross-regional reserve market clearing, thereby fully calling the power reserve resources of each region, improve the reserve adequacy of region as a whole, more can reduce system reserve total cost, improve the operation efficiency of regional power system, and it has great significance to power system marketization reform.

Description

Technical Field

[0001] This invention relates to the field of electrical engineering, and more specifically, to a method for clearing out cross-regional power reserve markets that takes into account transmission line reserve capacity. Background Technology

[0002] With the advancement of electricity market liberalization, the role of regional electricity markets in optimizing the allocation of electricity resources on a larger scale is becoming increasingly prominent, and the electricity reserve market is also gradually improving. In the process of building inter-regional reserve markets, how to achieve the clearing of inter-regional electricity reserves has become an urgent problem to be solved. When clearing inter-regional reserve markets, considering the reserve capacity of transmission lines can fully utilize the electricity reserve resources of each region, improve the overall reserve adequacy of the region, reduce the total system reserve cost, and improve the operating efficiency of the regional power system, which is of great significance to the market-oriented reform of my country's power system. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a method for clearing the cross-regional power reserve market that takes into account the reserve capacity of transmission lines, which improves the regional reserve adequacy, reduces the regional reserve market clearing price and the total system reserve cost, thereby improving the operating efficiency of the regional power system.

[0004] The technical solution adopted by this invention to solve its technical problem is: to construct a method for clearing the cross-regional power reserve market that considers the reserve capacity of transmission lines, including the following steps:

[0005] S1. The electricity spot market is pre-cleared based on the spot market clearing model to obtain the nodal price and the output curve of each unit at each time point;

[0006] S2. Opportunity cost of the computer group's standby market based on the results of the electricity spot market clearing;

[0007] S3. The unit submits a quantity and price quote in the spot-standby joint clearing market;

[0008] S4. Based on the unit's reported quantity and price data and the electricity demand and reserve demand in the electricity market, establish a spot-reserve joint clearing model to conduct joint optimization clearing of the spot-reserve market.

[0009] According to the above scheme, the constraints of the spot market clearing model in step S1 include:

[0010] Constraints on the upper and lower limits of the unit's active power output

[0011]

[0012] In the formula, This indicates the start / stop status of the i-th generating unit in region k during time period t. This represents the active power output of the i-th generating unit in region k during time period t;

[0013] Unit ramping constraints

[0014]

[0015] In the formula, and These represent the maximum uphill and downhill rates of unit i in region k, respectively.

[0016] Minimum continuous start-up and shutdown time constraints of the unit

[0017]

[0018] In the formula T U T D These are the minimum continuous start-up time and minimum continuous shutdown time of the unit, respectively.

[0019] System energy balance constraints

[0020]

[0021] In the formula, D t,k This represents the system load of region k during time period t. This represents the power exchange between region j and region k during time period t. This value is limited by the maximum transmission capacity of the transmission line. With minimum conveying capacity L j,k Ψ k This represents the set of other regions connected to region k via a region transmission line.

[0022] System reliability constraints

[0023]

[0024] In the formula, I k i R represents the capacity of the i-th unit in region k. d R w With R s These are the reserve requirement ratio of the power load, and the prediction error coefficients for wind power output and photovoltaic power output, respectively. This represents the reserve power that energy storage type z in region k can provide during time period t;

[0025] The objective function of the spot market clearing model is to minimize the system's power generation cost, expressed as follows:

[0026]

[0027] In the formula, T represents the total number of time periods considered. Let these represent the operating cost and start-up cost of the i-th generating unit in region k during time period t, respectively; the unit operating cost... It is a multi-segment linear function relating the output ranges declared by the generating unit to the corresponding prices.

[0028] According to the above scheme, the formula for calculating the opportunity cost of the unit standby market in step S2 is as follows:

[0029]

[0030] In the formula, LMP represents the market opportunity cost of the standby power supply for the i-th generator unit in region k during time period t. k,t The node price represents the electricity price at which the spot market clears. This represents the marginal cost of generating electricity for the i-th generating unit in region k. T0 represents the active power output of the i-th generator unit in region k during time period t, where T0 represents the calculation period.

[0031] According to the above scheme, in step S3, the reserve market price in the spot-reserve joint clearing market is based on the reserve market opportunity cost of the generating unit in a perfectly competitive electricity market with moderate market concentration.

[0032] According to the above scheme, in step S4, the model constraints and modified objective function of the spot-reserve joint clearing model based on the spot market are as follows:

[0033] Unit output upper and lower limits considering standby

[0034]

[0035] Considering spare transmission line capacity constraints

[0036]

[0037] In the formula, and The reserve capacity provided by the i-th unit in region k during time period t, and the reserve capacity provided by region j to region k during time period t.

[0038] Regional spare constraints

[0039]

[0040] In the formula, R t,k Ψ represents the total reserve requirement of region k during time period t. k This represents the set of other regions connected to region k via cross-regional transmission lines.

[0041] Objective function of the joint clearing model

[0042]

[0043] The formula for calculating the standby market price used in the joint clearing model is as follows:

[0044]

[0045] The cross-regional power reserve market clearing method considering transmission line reserve capacity, as described in this invention, has the following beneficial effects:

[0046] 1. This invention uses the pre-clearing results of the spot market to calculate the opportunity cost of the generator standby market, forms the standby market price of the generator, and then uses the spot-standby joint clearing model to simultaneously optimize the spot market and standby market of the generator and the cross-regional transmission line. This can improve the regional standby adequacy, reduce the regional standby market clearing price and the total system standby cost, thereby improving the operating efficiency of the regional power system.

[0047] 2. This invention can optimize the reserve capacity provided by transmission lines during the clearing of cross-regional reserve markets, thereby fully utilizing the power reserve resources of each region, improving the overall reserve adequacy of the region, reducing the total reserve cost of the system, and improving the operating efficiency of the regional power system. It is of great significance to the market-oriented reform of the power system. Attached Figure Description

[0048] The present invention will be further described below with reference to the accompanying drawings and embodiments. In the accompanying drawings:

[0049] Figure 1 This is a comparison chart of reserve market clearing prices before and after the present invention's method for clearing the cross-regional power reserve market, which takes into account the reserve capacity of transmission lines. Detailed Implementation

[0050] To provide a clearer understanding of the technical features, objectives, and effects of the present invention, specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0051] like Figure 1 As shown, the cross-regional power reserve market clearing method of the present invention, which considers transmission line reserve capacity, includes the following steps:

[0052] S1. The electricity spot market pre-clears based on the spot market clearing model to obtain the nodal price and the output curve of each unit at each time point.

[0053] The constraints of the spot market clearing model include:

[0054] Constraints on the upper and lower limits of the unit's active power output

[0055]

[0056] In the formula, This indicates the start / stop status of the i-th generating unit in region k during time period t. This represents the active power output of the i-th generating unit in region k during time period t.

[0057] Unit ramping constraints

[0058]

[0059]

[0060] In the formula, and These represent the maximum uphill and downhill rates of unit i in region k, respectively.

[0061] Minimum continuous start-up and shutdown time constraints of the unit

[0062]

[0063] In the formula T U T D These are the minimum continuous start-up time and the minimum continuous shutdown time of the unit, respectively.

[0064] System energy balance constraints

[0065]

[0066] In the formula, D t,k This represents the system load of region k during time period t. This represents the power exchange between region j and region k during time period t. This value is limited by the maximum transmission capacity of the transmission line. With minimum conveying capacity L j,k Ψ k This represents the set of other regions connected to region k via regional connection lines.

[0067] System reliability constraints

[0068]

[0069] In the formula, R represents the capacity of the i-th unit in region k. d R w With R s These are the reserve requirement ratio of the power load, and the prediction error coefficients for wind power output and photovoltaic power output, respectively. This represents the reserve power that energy storage type z in region k can provide during time period t.

[0070] The objective function of the spot market clearing model is to minimize the system's power generation cost, expressed as follows:

[0071]

[0072] In the formula, T represents the total number of time periods considered. Let represent the operating cost and start-up cost of the i-th generating unit in region k during time period t, respectively. Unit operating cost It is a multi-segment linear function relating the output ranges declared by the generating unit to the corresponding prices.

[0073] S2. Opportunity cost of the standby market for computer units, based on the results of the electricity spot market clearing.

[0074] For every 1MW of reserve capacity provided by a generator set in the reserve market, the available generating capacity in the spot market decreases by 1MW. Therefore, the opportunity cost of a generator set participating in the reserve market is the profit per unit of generating capacity when the set participates in the spot market.

[0075] The opportunity cost of the unit's standby market is expressed as follows:

[0076]

[0077] In the formula, LMP represents the market opportunity cost of the standby power supply for the i-th generator unit in region k during time period t. k,t The node price represents the electricity price at which the spot market clears. T0 represents the marginal generation cost of the i-th generating unit in region k, and T0 represents the calculation period.

[0078] S3. The unit submits a quantity and price quote in the spot-standby joint clearing market.

[0079] In a perfectly competitive electricity market with moderate market concentration, the spot market bid for generating units will approach their marginal generation cost, while the standby market bid will approach their standby market opportunity cost. In this model, the total amount of bids submitted by generating units in the joint clearing market of spot and standby is generally equal to the total available capacity of the generating units.

[0080] S4. Conduct joint optimization clearing of the spot and reserve markets. Considering the constraints of both the spot and reserve markets, a joint clearing model is established to optimize the clearing of both markets. This model can yield the nodal price, reserve price, output of each generating unit, and reserve capacity provided by each generating unit at each time point.

[0081] The spot-standby market joint clearing model is based on the spot market clearing model in step S1, with the addition of constraints considering unit standby and a change to the objective function.

[0082] The added constraints to the spot-alternate market joint clearing model include:

[0083] Unit output upper and lower limits considering standby

[0084]

[0085] Considering spare transmission line capacity constraints

[0086]

[0087] In the formula, and The reserve capacity provided by the i-th unit in region k during time period t, and the reserve capacity provided by region j to region k during time period t.

[0088] Regional spare constraints

[0089]

[0090] In the formula, R t,k This represents the total reserve requirement for region k during time period t.

[0091] The objective function of the joint clearing model is to minimize the sum of system generation cost and system reserve cost, as expressed below:

[0092]

[0093] Similar to the nodal pricing mechanism in the spot market, the clearing price calculation method for the reserve market is as follows:

[0094]

[0095] Example

[0096] A case study is conducted using actual data from a set of regions S (containing four adjacent regions A, B, C, and D). The total installed capacity of various types of units in each region is shown in Table 1, and the transmission line capacity limitations are shown in Table 2.

[0097] Table 1. Installed Capacity by Region (Unit: MW)

[0098]

[0099]

[0100] Table 2. Transmission Line Capacity Across Regions (Unit: MW)

[0101] transmission line A→B B→A B→C C→B capacity 7000 6700 5500 2500 transmission line B→D D→B C→D D→C capacity 3200 1800 2600 2600

[0102] The inter-regional power reserve market was cleared over an annual period of 8760 hours using this method, with the clearing results of the reserve market without considering inter-regional reserve transmission as a comparison. The average reserve market clearing price of the region set S is compared to... Figure 1As shown in Table 3, after adopting this optimized clearing method, the overall clearing price of the reserve market decreased significantly, and the price spikes in the reserve market were significantly reduced. The reserve adequacy, reserve market price, and total reserve market cost for each region before and after optimization are shown in Table 3.

[0103] Table 3 Comparison of standby market clearing results before and after adopting the cross-regional power standby market clearing method.

[0104]

[0105] This optimization clearing method optimizes the cross-regional reserve capacity provided by transmission lines. As shown in Table 3, through inter-regional reserve mutual assistance, the period of reserve shortage in region set S is significantly reduced, the cumulative reserve shortage value is significantly reduced, and the reserve price in each region drops significantly. The total annual reserve market cost of region set S is reduced from RMB 1.571 billion to RMB 501 million, a reduction of 68.1%, which is very effective.

[0106] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims. All of these forms are within the protection scope of the present invention.

Claims

1. A method for clearing the inter-regional power reserve market considering transmission line reserve capacity, characterized in that, Includes the following steps: S1. The electricity spot market is pre-cleared based on the spot market clearing model to obtain the nodal price and the output curve of each unit at each time point; S2. Opportunity cost of the computer group's standby market based on the results of the electricity spot market clearing; The formula for calculating the opportunity cost of the unit's standby market is as follows: In the formula, Let represent the market opportunity cost of standby for the i-th generating unit in region k during time period t. The node price represents the electricity price at which the spot market clears. This represents the marginal cost of generating electricity for the i-th generating unit in region k. Let represent the active power output of the i-th generating unit in region k during time period t. Indicates the calculation period; S3. The unit submits a quantity and price quote in the spot-standby joint clearing market; S4. Based on the unit's reported quantity and price data and the electricity demand and reserve demand in the electricity market, establish a spot-reserve joint clearing model to conduct joint optimization clearing of the spot-reserve market; The aforementioned spot-backed joint clearing model, based on the spot market, adds the following model constraints and modifies the objective function: Unit output upper and lower limits considering standby Considering spare transmission line capacity constraints In the formula, This indicates the start / stop status of the i-th generating unit in region k during time period t. This represents the power exchange between region j and region k during time period t. This value is limited by the maximum transmission capacity of the transmission line. With minimum conveying capacity , and Let represent the reserve capacity provided by the i-th unit in region k during time period t, and the reserve capacity provided by region j to region k during time period t, respectively. Regional spare constraints In the formula, This represents the total reserve requirement for region k during time period t. This represents the set of other regions connected to region k via cross-regional transmission lines. Objective function of the joint clearing model In the formula, T represents the total number of time periods considered. , Let these represent the operating cost and start-up cost of the i-th generating unit in region k during time period t, respectively; the unit operating cost... It is a multi-segment linear function relating the output ranges declared by the generating unit to the corresponding prices; The formula for calculating the standby market price used in the joint clearing model is as follows: 。 2. The method for clearing the inter-regional power reserve market considering transmission line reserve capacity according to claim 1, characterized in that, In S1, the constraints of the spot market clearing model include: Constraints on the upper and lower limits of the unit's active power output In the formula, This represents the active power output of the i-th generating unit in region k during time period t; Unit ramping constraints In the formula, and These represent the maximum uphill and downhill rates of unit i in region k, respectively. Minimum continuous start-up and shutdown time constraints of the unit In the formula , These are the minimum continuous start-up time and minimum continuous shutdown time of the unit, respectively. System energy balance constraints In the formula, This represents the system load of region k during time period t. This represents the set of other regions connected to region k via a region transmission line. System reliability constraints In the formula, This represents the capacity of the i-th generating unit in region k. , and These are the reserve demand ratio of electricity load and the prediction error coefficients for wind power output and photovoltaic power output, respectively. The objective function of the spot market clearing model is to minimize the system's power generation cost, expressed as follows: 。 3. The method for clearing the inter-regional power reserve market considering transmission line reserve capacity according to claim 1, characterized in that, In S3, the interim price quotes for the spot-standby joint clearing market are based on the standby market opportunity cost of the generating units in a perfectly competitive electricity market with moderate market concentration.

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