Power grid dispatching method for self-contained power supply peak in demand side corresponding mode

Abstract

The invention discloses a power grid dispatching method for a self-contained power supply peak in a demand side corresponding mode, and belongs to the field of self-contained power supply participation market dispatching. The power grid dispatching method for the self-contained power supply peak in the demand side corresponding mode comprises the steps that feasibility of grid-connected operation of a self-contained power supply is analyzed, and operation cost models of a typical self-contained power supply are established and comprise a self-contained diesel generator operation cost model, a self-contained energy storage operation cost model and a triple co-generation dispatching cost model; setting a market mechanism of a self-contained power supply peak in a demand side response mode, and establishing a self-contained power supply user Bayesian quotation model based on the operation cost model of the typical self-contained power supply; taking the minimum operation cost of the power grid as a target, solving the Bayesian quotation model of the self-contained power supply user by using MATLAB, and calculating the optimal compensation electricity price; therefore, the objective of safe and stable operation of the system can be achieved, the operation cost of the power grid is remarkably reduced, and the power transmission pressure of the power distribution network at the power utilization peak is relieved.

Description

Technical Field

[0001] The present invention belongs to the field of self-provided power supply participating in market dispatching, and in particular relates to a power grid dispatching method for a self-provided power supply peak under a demand side corresponding mode. Background Art

[0002] In the current context of increasingly tense power supply and demand, the power grid often faces the dilemma of imbalance between supply and demand during peak power consumption. With the increase in population and rapid economic development, power demand continues to rise, resulting in a serious shortage of power supply during peak hours. During the high temperature period in summer, the concentrated use of large power consumers such as air conditioners makes the power grid load almost reach its carrying limit. In order to solve this problem, using the company's own power supply to participate in the peak power grid dispatch has become a feasible way.

[0003] The enterprise's self-provided power supply has flexibility and instant response capabilities. When the load on the power grid increases, it can quickly start generating electricity to meet the urgent demand for electricity. Compared with traditional power grid power generation methods, self-provided power supply can not only reduce the pressure on the power grid, but also improve the stability of the system and reduce the risk of power failure caused by peak load fluctuations. Therefore, the reasonable design of a market mechanism for self-provided power supply to participate in power grid dispatch can not only optimize resource allocation, but also improve the economy and reliability of the power system.

[0004] However, at the current stage, there is a relative lack of peak participation mechanisms for self-provided power supplies of enterprises. Although self-provided power supplies can play a good role in dealing with power peaks, there is a lack of effective market mechanisms to regulate and guide their participation in grid dispatching. This has caused many enterprises to be unable to include their self-provided power supplies in grid dispatching in time during peak periods, missing the best opportunity to match power supply and demand. For this reason, a grid dispatching method for self-provided power supply peaks under the demand-side corresponding mode is proposed. Summary of the invention

[0005] In view of the deficiencies in the prior art, the purpose of the present invention is to provide a grid dispatching method for a self-provided power supply peak in a demand-side corresponding mode, which solves the problems in the prior art.

[0006] The purpose of the present invention can be achieved through the following technical solutions:

[0007] A method for dispatching a power grid with a self-provided power supply peak in a demand side corresponding mode comprises the following steps:

[0008] Analyze the feasibility of grid-connected operation of self-provided power supply and establish the operation cost model of typical self-provided power supply, including: self-provided diesel generator operation cost model, self-owned energy storage operation cost model and trigeneration dispatch cost model;

[0009] Setting up a market mechanism for the peak of self-provided power supply under the demand-side response mode, and establishing a Bayesian quotation model for self-provided power supply users based on the operation cost model of the typical self-provided power supply;

[0010] The goal is to minimize the grid operation cost, and MATLAB is used to solve the Bayesian quotation model of the self-provided power user to calculate the optimal compensation electricity price.

[0011] Furthermore, the operating cost model of the self-provided diesel generator is:

[0012]

[0013] In the formula, C dg is the unit time cost of self-provided diesel generator, P dg Indicates the self-provided diesel power generation, a dg 、b dg 、c dg and d dg All are operating constants of self-contained power diesel generators.

[0014] Furthermore, the self-owned energy storage operation cost model is:

[0015] C s =α s P s / η d

[0016] Where P s is the energy storage output power, η d Represents the discharge efficiency of electrochemical energy storage, C s is the unit time cost of dispatching energy storage, α s Represents the unit capacity cost.

[0017] Furthermore, the trigeneration scheduling cost model is:

[0018]

[0019] In the formula, C tr is the trigeneration dispatching cost, P tr represents the gas turbine output power, a tr 、b tr and c tr is the trigeneration operation constant.

[0020] Furthermore, the Bayesian quotation model of the self-provided power supply user is:

[0021]

[0022] Q(P sb )=cop

[0023]

[0024] F(P)=kC(P)+b

[0025] Where F(P) represents the quotation curve, C(P) represents the cost curve, P represents the declared capacity, k and b are the quotation parameters; Q is the unit quotation with respect to the declared capacity P sb In order to balance the power of the power grid in real time, the model needs to introduce power generation equipment that can balance the power, which can be the main power grid; mcp t * represents the clearing electricity price at time t on the day, represents the average of the power grid clearing price at the same time t in the previous ten days, σ 2 (mcp t ) represents the variance of the clearing electricity price at the same time t in the previous ten days. 2 ) indicates that today's clearing electricity price follows a normal distribution with μ as the central value and σ 2 is the variance; P Lt represents the total grid load at time t; represents the dispatch capacity forecast of the self-provided power supply at time t on the day, P L Represents the total load of the power grid, P z Indicates the response capacity of the self-contained power supply. It represents the forecast of total load at time t of the day; Represents the linear fit P L and P z The forecast of total load at time t on the day is P z Bring in your own power supply to generate power; E xi represents the expected benefit of self-provided power user i in the demand-side response mode, T is the total dispatch time; f mcp and They represent the probability distribution of clearing electricity price and the probability distribution of total load at time t respectively; m i (k,b)≤0 is the restriction condition for user i.

[0026] Furthermore, the specific process of calculating the optimal compensation electricity price is as follows:

[0027] The operating cost of the power system considering the self-provided power supply is:

[0028]

[0029] Where D x is the total grid operation cost during peak hours under the demand-side response mode; C ht (P ht ) and C zt (P zt) are the unit time operation costs of the thermal power units of the power grid and the self-provided power supply at time t respectively;

[0030] The unit time operation cost of thermal power units in the power grid is:

[0031]

[0032] In the formula, C h (P h ) is the unit time cost of dispatching thermal power units, P h The power generated by the thermal power unit, a h , and are the operating constants of thermal power units.

[0033] The unit time operating cost of the self-provided power supply is:

[0034] C z (P z )=cop*P z

[0035] In the formula, C z (P z ) is the unit time dispatching cost of self-provided power supply, cop is the unit compensation price of self-provided power supply, P z Generate power for your own power supply.

[0036] The optimization problem is expressed as:

[0037]

[0038] If only the equality constraints are considered, the Lagrangian function for scheduling optimization is:

[0039]

[0040] Where P Lt is the total load of the power grid at time t, λ t are the T Lagrangian operators introduced; in order to minimize the power grid operation cost, then:

[0041]

[0042] If the self-provided power supply does not reach the maximum value in all time periods, it means that the unit compensation price of the self-provided power supply is high, and reducing the compensation price can achieve the same peak effect; there is at least one period when the self-provided power supply dispatch power reaches the total declared capacity; suppose the self-provided power supply full-time period is the set S = {1,2,…s}, then:

[0043]

[0044] In the formula is the derivative of the Lagrangian function to the power of the thermal power unit, where is the derivative of the Lagrangian function to the power of the self-provided power supply when the self-provided power supply is not fully generated, where is the derivative of the Lagrangian function of the self-provided power supply when the self-provided power supply is fully generated, s is the number of full-generation time periods, where is the derivative of the Lagrangian function with respect to the Lagrangian factor, which is also the equality constraint. Lt is the load power at time t;

[0045] Among them, formula c means that the maximum power of the self-provided power supply is used for scheduling during these s time periods, and the output power of the self-provided power supply is the same during these s time periods; and there is a functional relationship between the unit compensation electricity price and the maximum response capacity.

[0046] Furthermore, the constraints when using MATLAB to solve the Bayesian quotation model for self-provided power users include:

[0047] P dgmin ≤P dg ≤P dgmax

[0048]

[0049] P smin ≤P s ≤P smax

[0050]

[0051] 0.1SOC max ≤SOC t ≤0.9SOC max

[0052]

[0053] P e =η e P tr

[0054] P R =(1-η e ) tr

[0055] P ht =η h P R

[0056]

[0057]

[0058] P trmin <P tr <P trmax

[0059] P emin <P e <P emax

[0060]

[0061] g(P ht ,P zt )=0

[0062] Where P dgmin and P dgmax They represent the minimum and maximum power output of the self-provided diesel generator respectively; Gd max Indicates the maximum climbing rate; P smin , P smax Respectively represent the minimum and maximum values ​​allowed for energy storage output; SOC 0 is the state of charge at the beginning of scheduling, SOC max is the maximum state of charge of the energy storage device, SOC t is the state of charge at time t; C tr is the trigeneration dispatching cost, P tr Indicates the gas turbine output power; P e represents the power generation of the gas turbine, η e Indicates the efficiency of the gas turbine in generating electrical power; P R is the power generated by the waste heat boiler, P ht is the sum of the power generated by the waste heat boiler converted into cooling and heating power, η h is the conversion efficiency; P cool and P heat Represent the power required for cooling load and heating load respectively, η cool and η heat Describe the efficiency of cooling and heating equipment respectively; η g represents the ratio of gas turbine input to generator, α represents the adjustable range of equivalent heat load; P trmin and P trmax They represent the minimum and maximum power output of the gas turbine, P emin and P emax Respectively represent the minimum and maximum power limits of the generator set output; P i is the injected power of node i, g(P ht ,P zt ) is the power system flow calculation algorithm, and 0 indicates power balance.

[0063] A power grid dispatching system for a self-provided power supply peak in a demand side corresponding mode, comprising:

[0064] Cost model building module: Analyze the feasibility of grid-connected operation of self-provided power supply and establish the operation cost model of typical self-provided power supply, including: self-provided diesel generator operation cost model, self-owned energy storage operation cost model and trigeneration dispatch cost model;

[0065] The quotation model building module is used to set the market mechanism of the self-provided power supply peak under the demand-side response mode, and to establish a Bayesian quotation model for self-provided power supply users based on the operation cost model of the typical self-provided power supply;

[0066] And, the model solving module: takes the minimization of the grid operation cost as the goal, and uses MATLAB to solve the Bayesian quotation model of the self-provided power supply user to calculate the optimal compensation electricity price.

[0067] A computer storage medium stores a readable program, which can execute the above-mentioned power grid dispatching method for a self-provided power supply peak in a demand side corresponding mode when the program is running.

[0068] An electronic device, comprising: a processor, a memory, a communication interface and a communication bus, wherein the processor, the memory and the communication interface communicate with each other through the communication bus;

[0069] The memory is used to store at least one executable instruction, and the executable instruction enables the processor to execute operations corresponding to the above-mentioned power grid scheduling method for the peak of self-provided power supply in a demand side corresponding mode.

[0070] Beneficial effects of the present invention:

[0071] 1. The present invention establishes an operating cost function model of the active distribution network of self-provided power supply, proposes a market mechanism for the peak of self-provided power supply under the demand-side response mode, establishes a Bayesian quotation model for self-provided power supply users under the market mechanism, and calculates the optimal compensation electricity price under the demand-side response mode, thereby achieving the goal of safe and stable operation of the system, significantly reducing the operating cost of the power grid, and alleviating the transmission pressure of the distribution network during peak power consumption.

[0072] 2. The present invention sets up a market mechanism for the peak of self-generated power supply under the demand-side response mode, and establishes a Bayesian quotation model for self-generated power supply users under this market mechanism, thereby providing a scientific decision-making basis for self-generated power supply users to participate in power system dispatching, effectively improving the benefits of self-generated power supply users, and providing guidance for the comprehensive utilization of self-generated power supply users' resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0073] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0074] Figure 1 is the power grid topology diagram in Embodiment 2 of the present invention;

[0075] Figure 2 is a typical daily load curve in Example 2 of the present invention;

[0076] Figure 3 is the operating cost-maximum load curve under two scenarios in Example 2 of the present invention;

[0077] Figure 4 is a power flow distribution diagram of a traditional power grid in Embodiment 2 of the present invention;

[0078] Figure 5 is a power flow distribution diagram of a power grid taking into account a self-provided power supply in Embodiment 2 of the present invention;

[0079] Figure 6 It is a flow chart of the power grid dispatching method of the present invention. DETAILED DESCRIPTION

[0080] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0081] Example 1

[0082] like Figure 6 As shown, a grid dispatching method for a self-provided power supply peak in a demand side corresponding mode comprises the following steps:

[0083] S1, analyze the feasibility of grid-connected operation of self-provided power supply and establish the operation cost model of typical self-provided power supply;

[0084] Typical operating cost models of self-provided power sources include: self-provided diesel generator operating cost model, self-owned energy storage operating cost model and trigeneration scheduling cost model.

[0085] 1) The operating cost model of a self-provided diesel generator is:

[0086]

[0087] In the formula, Cdg is the unit time cost of self-provided diesel generator, in RMB / hour, P dg Indicates the self-provided diesel power generation, a dg 、b dg 、c dg and d dg All are operating constants of self-contained diesel generators. From the formula, it can be seen that the operating cost of self-contained diesel generators can be composed of two parts, one of which is a quadratic function of the generated power. The other part is proportional to the rate of change of power, which is called the ramp cost.

[0088] The operating restrictions of the self-provided diesel generator are as follows:

[0089] Power upper and lower limits:

[0090] P dg min ≤P dg ≤P dg max (2)

[0091] Where: P dgmin and P dgmax They respectively represent the minimum and maximum power allowed to be output by the self-contained diesel generator.

[0092] Climbing limit:

[0093]

[0094] Where: Gd max Indicates the maximum climbing rate.

[0095] 2) The operating cost model of self-owned energy storage can be expressed as the following formula:

[0096] C s =α s P s / η d (4)

[0097] Where P s is the energy storage output power, η d Represents the discharge efficiency of electrochemical energy storage, C s is the unit time cost of dispatching energy storage, unit time (yuan / hour), α s Represents the unit capacity cost.

[0098] When scheduling, self-owned energy storage must meet the following restrictions.

[0099] Output power limit:

[0100] P smin ≤P s ≤Psmax (5)

[0101] Where: P smin , P smax They represent the minimum and maximum values ​​allowed for the energy storage output respectively.

[0102] State of Charge Limits:

[0103] 0.1SOC max ≤SOC t ≤0.9SOC max (6)

[0104] Where: SOC max is the maximum state of charge of the energy storage device, SOC t is the state of charge at time t. For electrochemical energy storage, the state of charge needs to be between the maximum and minimum allowable battery capacity. According to experience, the best value is 0.1 and 0.9 times the full charge state.

[0105] State of charge calculation:

[0106]

[0107] Where: SOC 0 is the charge state at the beginning of scheduling.

[0108] 3) The participation of trigeneration in self-generated power dispatch means participating in grid dispatch when meeting its own heat load demand, that is, operating in the FTL mode.

[0109] The trigeneration unit satisfies the following basic equation:

[0110]

[0111] P e =η e P tr (9)

[0112] P R =(1-η e ) tr (10)

[0113] P ht =η h P R (11)

[0114]

[0115] In formula (8), C tr is the trigeneration dispatching cost, P trrepresents the output power of the gas turbine. The formula shows that the trigeneration scheduling cost is in a quadratic function relationship with the output power of the gas turbine. e represents the power generation of the gas turbine, η e Indicates the efficiency of the gas turbine in generating electrical power. R is the power generated by the waste heat boiler, P in formula (11) ht is the sum of the power generated by the waste heat boiler converted into cooling and heating power, η h is the conversion efficiency. In formula (12), P cool and P heat Represent the power required for cooling load and heating load respectively, η cool and η heat The above formulas show the conversion and quantitative relationship between various powers of trigeneration. The conversion between various powers of trigeneration is roughly as follows: the power output by the gas turbine is converted into electrical power through the power generation equipment, and the remaining power is the boiler preheating power. The waste heat power of the boiler is used to generate the power required for the cooling and heating loads through the cooling and heating equipment.

[0116] The following restrictions on adjustable heat load must be met during trigeneration operation:

[0117]

[0118] Where η g represents the ratio of gas turbine input to generator, and α represents the adjustable range of equivalent heat load.

[0119] In addition, trigeneration should also meet the gas turbine output power limit:

[0120] P trmin <P tr <P trmax (14)

[0121] Where P trmin and P trmax They represent the minimum and maximum power output of the gas turbine respectively.

[0122] Generator output power limit:

[0123] P emin <P e <P emax (15)

[0124] Where P emin and P emax Respectively represent the minimum and maximum power limits of the generator set output.

[0125] After the self-provided power supply is connected to the grid, it will affect the voltage of the power system because of the change in the impedance and reactive power flow of the grid. In general, the voltage of the access point will be raised when the self-provided power supply is connected to the system. If the self-provided power supply user sends power back to the grid at this time, the voltage rise phenomenon at the access point will be more obvious. If the self-provided power supply user chooses not to use the self-provided power supply because the city electricity price is low, and the user's power consumption happens to be large at this time, then the voltage at the access point will drop. In summary, the connection of the self-provided power supply to the grid will increase the voltage fluctuation at the access point. Therefore, in order to ensure the voltage quality of the power grid. It is necessary to use a combination of on-load voltage regulation and capacitor switching to connect the self-provided power supply to improve the ability of the power grid to regulate voltage. In addition, if there is a situation where a large self-provided power supply is connected to the end of the power grid, it is very likely that the fluctuation of the power grid voltage will exceed the regulation ability of the power grid, further increasing the difficulty of power grid voltage balance.

[0126] On the other hand, when a short-circuit fault occurs in the system, the grid-connected self-contained power supply will inject short-circuit current into the fault point through the access point. At the same time, the grid-connected operation of large self-contained power supplies will also increase the short-circuit capacity of the power grid, which may deteriorate the dynamic thermal stability of electrical equipment. If the short-circuit capacity at this time is close to the rated interrupting capacity of the selected circuit breaker, it may bring danger to the system. Therefore, when a large self-contained power supply is connected to the grid, it is necessary to consider appropriately adjusting the rated interrupting capacity.

[0127] The connection of the user's own power supply to the grid will change the power supply structure of the local power supply area, and the conventionally configured relay protection device can no longer meet the system requirements. The changed short-circuit current will also reduce the selectivity and sensitivity of the relay protection equipment and increase the difficulty of setting calculations. If the existing configuration and setting technology of relay protection and automatic devices cannot cope with this change well, it is very likely that the device will not operate correctly, causing damage to the equipment and even leading to the expansion of the accident. Therefore, after the self-provided power supply is connected to the grid, it is necessary to reconsider the neutral point grounding method of the system substation. At the same time, the reclosing, backup power supply automatic investment and main transformer backup protection devices need to be adjusted and modified accordingly. Thereby ensuring the safe and stable operation of the power grid.

[0128] In summary, the use of self-provided power to participate in the peak of the power system requires the power grid to have a good enough voltage regulation capability, and to make corresponding modifications and adjustments to the configuration of the corresponding relay protection and automatic devices to meet the requirements of the self-provided power supply to return power to the power grid under the market model. At the same time, when a power grid failure occurs, small self-provided power users must be quickly cut off to ensure the safe operation of the main grid and restore the main grid power supply as soon as possible.

[0129] S2, setting up the market mechanism for the peak of self-provided power supply under the demand-side response mode, and establishing a Bayesian quotation model for self-provided power supply users based on the operation cost model of the typical self-provided power supply established in S1;

[0130] The market mechanisms of the demand-side response model include:

[0131] There are three forms of load incentives in the current demand-side response market. They are annual long-term contracts, monthly bidding and the day-ahead market. Among them, the annual long-term contract refers to a fixed electricity price agreement signed between power generation companies and power plants with an annual cycle, which helps both parties to better plan and manage electricity supply and demand. In demand-side response, it can refer to an agreement signed by load reduction users to high-power users. Monthly bidding refers to power generation companies participating in centralized monthly bidding every month, and settling at the agreed electricity price after deriving the agreed electricity price. The last one is the day-ahead market, where users participate in the day-ahead bidding, and then the market settles at a 24-hour time-of-use electricity price. Or settle with users at the peak, valley and flat three-period electricity prices.

[0132] For the self-provided power supply peak mechanism, since the cost of self-provided power generation is higher than that of traditional power grid power generation enterprises, its advantage in participating in annual long-term contracts and monthly bidding is weak, so it is not suitable for the first market mechanism. At the same time, the peak needs to have a clear grasp of the load curve during the peak period of electricity consumption in order to accurately reflect the supply and demand situation of the peak period of the electricity market, so as to achieve the lowest cost of power grid operation. Therefore, it is proposed here to encourage self-provided power supply to go online for power generation by means of the unit peak compensation electricity price formulated by the government a few days ago, and to charge a certain assessment fee when the power deviation of the market entity exceeds 2%.

[0133] The Bayesian quotation model construction process includes:

[0134] The user-side power supply bidding strategy used in the model is a linear bidding based on power generation cost:

[0135] F(P)=kC(P)+b (16)

[0136] In the formula, F(P) represents the quotation curve, C(P) represents the cost curve, that is, the cost of the self-provided power supply established in S1, P represents the declared capacity (power), k and b are quotation parameters. For the quotation curve, if both sides of the equation are divided by the declared power P, it can be regarded as the unit electricity price declared by the user, that is:

[0137]

[0138] When the unit electricity price declared by the user is the same as the unit peak compensation electricity price set by the government, the power at that time can be solved inversely, and the power at that time can be regarded as the capacity declared by the user, that is:

[0139] Q(P sb ) = cop (18)

[0140] Where Q is the unit price for declared capacity P sbfunction, cop is the compensation price of self-provided power supply. In order to balance the power of the power grid in real time, it is necessary to introduce power generation equipment that can balance power into the model, which can be the main power grid.

[0141] Assume that the hourly clearing electricity price of the power grid in recent days can be considered to conform to the normal distribution, and take the hourly clearing electricity price of the past 10 days as a sample. The same treatment is performed on the load curve in recent days.

[0142]

[0143] In the formula, mcp t * represents the clearing electricity price at time t on the day, represents the average of the power grid clearing price at the same time t in the previous ten days, σ 2 (mcp t ) represents the variance of the clearing electricity price at the same time t in the previous ten days. 2 ) indicates that today's clearing electricity price follows a normal distribution with μ as the central value and σ 2 is the variance.

[0144] The total value of the power grid load on the same day also conforms to the normal distribution:

[0145]

[0146] Where P Lt Represents the total grid load at time t. Similar to formula (19). It should be emphasized here that the user's prediction of grid load cannot be done through the grid prediction method used in general dispatching, but can only predict the total load of the day through the results of previous games.

[0147] During grid dispatch, if the grid unit clearing price is higher than the self-provided power supply compensation price, the self-provided power supply will send out the maximum power. If the clearing price is lower than the grid dispatch, the self-provided power supply will not participate in the dispatch. If the clearing price is equal to the self-provided power supply quotation, it means that the marginal cost of the thermal power units in the grid is equal to the compensation price, and the power shortage of the grid is made up by the self-provided power supply. Then, the user's self-provided power supply response capacity should be in a linear function relationship with the total load of the grid at this time. Therefore, when the clearing price is higher than the unit peak compensation price of the day, the self-provided power supply will report the full power, otherwise the power response of the self-provided power supply will be in a linear function relationship with the load curve of the grid. At this time, the dispatch capacity of the self-provided power supply is based on the total load of the previous ten days and the self-provided power supply dispatch capacity. The dispatch capacity of the day is calculated by linear fitting.

[0148]

[0149] In the formula, represents the dispatch capacity forecast of the self-provided power supply at time t on the day, P LRepresents the total load of the power grid, P z Indicates the response capacity of the self-contained power supply. Represents the forecast of total load at time t on the day. Represents the linear fit P L and P z The forecast of total load at time t on the day is P z Enter the power output of the self-provided power supply. The expected benefit of user i can be obtained:

[0150]

[0151] In formula (22), E xi represents the expected benefit of self-provided power user i under the demand-side response mode, assuming that the minimum time unit of scheduling is 1 hour, and T is the total scheduling time; f mcp and They represent the probability distribution of clearing electricity price and the probability distribution of total load at time t respectively.

[0152] Finally, the optimal bidding strategy is obtained by modifying the bidding parameters k and b to maximize the user's expected profit under the constraint of the user's self-provided power supply. The constraint condition of user i is m i The optimal quotation model with (k,b)≤0 can be expressed as:

[0153]

[0154] S3, with the goal of minimizing the grid operation cost, uses MATLAB to solve the Bayesian quotation model for self-provided power users constructed in S2 and calculate the optimal compensation electricity price;

[0155] The specific process of calculating the optimal compensation electricity price is as follows:

[0156] The operating cost of the power system considering self-provided power supply can be expressed by the following formula:

[0157]

[0158] Where D x is the total grid operation cost during peak hours under the demand-side response mode; C ht (P ht ) and C zt (P zt ) are the unit time operation costs of the thermal power units of the power grid and the self-provided power supply at time t. The unit time operation costs of the thermal power units of the power grid are as follows:

[0159]

[0160] In the formula, C h (P h ) is the unit time cost of dispatching thermal power units, Ph The power generated by the thermal power unit, a h , and are the operating constants of thermal power units.

[0161] Unit time operating cost of self-provided power supply:

[0162] C z (P z )=cop*P z (26)

[0163] In the formula, C z (P z ) is the unit time dispatching cost of self-provided power supply, cop is the unit compensation price of self-provided power supply, P z Generate power for your own power supply.

[0164] At the same time, the power balance constraints of the power system need to be met:

[0165]

[0166] Where P i is the injected power of node i, denoted as g(P ht ,P zt )=0.

[0167] Therefore, the optimization problem can be written as:

[0168]

[0169] If only the equality constraints are considered, the Lagrangian function of scheduling optimization can be written as:

[0170]

[0171] Where P Lt is the total load of the power grid at time t, λ t are the T Lagrangian operators introduced. In order to minimize the power grid operation cost, then:

[0172]

[0173] If the self-provided power supply does not reach the maximum value in all time periods, it means that the unit compensation price of the self-provided power supply is high, and the compensation price can be further reduced to achieve the same peak effect. And reduce the operating cost. Therefore, there is at least one period in which the self-provided power supply dispatch power reaches the total declared capacity. Suppose the self-provided power supply full-time period is a set S = {1,2,…s}, then:

[0174]

[0175] a is the derivative of the Lagrangian function with respect to the power of the thermal power unit, where is the derivative of the Lagrangian function of the self-provided power supply when the self-provided power supply is not fully generated, where is the derivative of the Lagrangian function of the self-provided power supply when the self-provided power supply is fully generated, s is the number of full-generation time periods, where is the derivative of the Lagrangian function with respect to the Lagrangian factor, which is also the equality constraint. Lt is the load power at time t.

[0176] Formula (30) C indicates that the maximum power of the self-provided power source is used for dispatching in these s time periods, and the output power of the self-provided power source is the same in these s time periods; and there is a functional relationship between the unit compensation electricity price and the maximum response capacity (declared capacity), which is obtained from the above quotation model; Substituting in, we can get formula C;

[0177] Formula (30) shows that during the period when the self-provided power supply is fully generated, at this compensation price, the benefits of increasing the capacity of the self-provided power supply due to the increase in the compensation price are smaller than those of directly calling the thermal power units. Therefore, the remaining power shortage of the power grid is generated by the thermal power units of the power grid. The power generation capacity of the self-provided power supply and the thermal power units are effectively utilized.

[0178] The constraints when solving the Bayesian quotation model for self-provided power users in MATLAB include:

[0179] (1) Diesel generator power constraints:

[0180] P dgmin ≤P dg ≤P dgmax

[0181] Where: P dgmin and P dgmax They respectively represent the minimum and maximum power allowed to be output by the self-contained diesel generator.

[0182] (2) Diesel generator climbing limit:

[0183]

[0184] In the formula, Gd max Indicates the maximum climbing rate.

[0185] (3) Output power limit of own energy storage:

[0186] P s min ≤P s ≤P s max

[0187] Where P s min , P s max They represent the minimum and maximum values ​​allowed for the energy storage output respectively.

[0188] (4) Calculation and limitation of state of charge of self-owned energy storage:

[0189]

[0190] 0.1SOC max ≤SOC t ≤0.9SOC max

[0191] Where: SOC 0 is the state of charge at the beginning of scheduling, SOC max is the maximum state of charge of the energy storage device, SOC t is the state of charge at time t.

[0192] (5) The trigeneration unit satisfies the basic equation:

[0193]

[0194] P e =η e P tr

[0195] P R =(1-η e ) tr

[0196] P ht =η h P R

[0197]

[0198] In the formula, C tr is the trigeneration dispatching cost, P tr Indicates the gas turbine output power; P e represents the power generation of the gas turbine, η e Indicates the efficiency of the gas turbine in generating electrical power; P R is the power generated by the waste heat boiler, P ht is the sum of the power generated by the waste heat boiler converted into cooling and heating power, η h is the conversion efficiency; P cool and P heat Represent the power required for cooling load and heating load respectively, η cool and η heat State the efficiency of cooling and heating equipment respectively.

[0199] (6) Restrictions on adjustable heat load of trigeneration:

[0200]

[0201] Where η g represents the ratio of gas turbine input to generator, and α represents the adjustable range of equivalent heat load.

[0202] (7) Output power limits of trigeneration gas turbines and generators:

[0203] P trmin <P tr <P trmax

[0204] P emin <P e <P emax

[0205] Where P trmin and P trmax They represent the minimum and maximum power output of the gas turbine, P emin and P emax Respectively represent the minimum and maximum power limits of the generator set output.

[0206] (8) Power system power balance limit:

[0207]

[0208] g(P ht ,P zt )=0

[0209] Where P i is the injected power of node i, g(P ht ,P zt ) is the power system flow calculation algorithm, and 0 indicates power balance.

[0210] Based on similar inventive concepts, an embodiment of the present invention also provides a computer storage medium storing a readable program, which, when running, can execute the above-mentioned grid dispatching method for the self-provided power supply peak in a demand side corresponding mode.

[0211] Based on similar inventive concepts, an embodiment of the present invention provides an electronic device, comprising: a processor, a memory, a communication interface and a communication bus, wherein the processor, the memory and the communication interface communicate with each other through the communication bus;

[0212] The memory is used to store at least one executable instruction, and the executable instruction enables the processor to execute operations corresponding to the above-mentioned power grid scheduling method for the peak of self-provided power supply in a demand side corresponding mode.

[0213] Based on similar inventive concepts, an embodiment of the present invention also provides a computer program product, including computer instructions, which instruct a computing device to execute operations corresponding to the above-mentioned grid dispatching method for a self-generated power supply peak in a corresponding mode on the demand side.

[0214] Example 2

[0215] In this embodiment, the effectiveness of the power grid dispatching method in Embodiment 1 is verified through a specific case;

[0216] The power grid topology diagram of this example is as follows: Figure 1 As shown, three different types of self-provided power sources are connected to nodes 6, 12 and 17 respectively. They are self-provided diesel generator, trigeneration and self-owned energy storage;

[0217] The parameters used in the model are shown in Table 1 below:

[0218] Table 1 Model parameters

[0219]

[0220] Through Figure 2 The daily load curve in the simulation is scaled proportionally to simulate the operation cost of the traditional power grid under different load curves and the peak power grid of the self-provided power supply under the demand-side response mode. A typical daily load curve is taken as the power flow distribution diagram.

[0221] Depend on Figure 3 It can be seen that the total operating cost of the power grid increases with the increase of the maximum total load. After adding the self-supplied power peak of the demand-side response mode, the total operating cost of the power grid is significantly lower than that of the traditional power grid. And with the increase of the maximum total load, the advantage of the self-supplied power peak in the demand-side response mode is more obvious. The power grid operation cost is significantly lower than that of the traditional power grid. However, the advantage in operating cost is not obvious enough when the maximum total load is low. This is because the clearing price of thermal power units is low when the total load is low. The compensation price of self-supplied power will not be higher than the clearing price of thermal power units, and the lower price cannot well stimulate the self-supplied power generation. When the maximum total load is high, the demand-side response mode has obvious advantages, because when the power grid demand is high. When the self-supplied power is declared at the highest capacity, there is no need to increase the compensation price, so the demand-side response mode has more obvious advantages over the traditional power grid in terms of operating costs, and has better peak effects when the power grid is in high demand.

[0222] Figure 4The middle shows the power flow distribution of the traditional power grid, and the red lines indicate overloaded lines; Figure 5 The figure in the figure shows the power flow distribution after the participation of self-provided power supply. Compared with the traditional power grid and the power grid considering self-provided power supply, the power flow distribution of the latter during the peak of power consumption is improved, and there is no cross-border phenomenon of power grid lines. After the participation of self-provided power supply at the peak, the load rate of the lines in the distribution network is 61.48%, which is also a significant decrease compared with the 77.56% of the traditional power grid. This is because the peak of self-provided power supply in the demand-side response mode weakens the load demand of the power grid, reduces the terminal power demand, improves the power flow distribution of the power grid, and improves the static safety of the power system.

[0223] Example 3

[0224] In this embodiment, a grid dispatching system for a self-provided power supply peak in a demand side corresponding mode is proposed, specifically including:

[0225] Cost model building module: Analyze the feasibility of grid-connected operation of self-provided power supply and establish the operation cost model of typical self-provided power supply;

[0226] The quotation model building module is used to set the market mechanism of the self-provided power supply peak under the demand-side response mode, and to establish a Bayesian quotation model for self-provided power supply users based on the operation cost model of the typical self-provided power supply;

[0227] And, the model solving module: takes the minimization of the grid operation cost as the goal, and uses MATLAB to solve the Bayesian quotation model of the self-provided power supply user to calculate the optimal compensation electricity price.

[0228] The method of the present invention may be implemented in hardware, firmware, or as software or computer code that may be stored in a recording medium (such as a CDROM, RAM, floppy disk, hard disk, or magneto-optical disk), or as computer code that is originally stored in a remote recording medium or a non-temporary machine-readable medium downloaded over a network and will be stored in a local recording medium, so that the method described herein may be stored in such software processing on a recording medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware (such as an ASIC or FPGA). It is understood that a computer, processor, microprocessor controller, or programmable hardware includes a storage component (e.g., RAM, ROM, flash memory, etc.) that can store or receive software or computer code, and when the software or computer code is accessed and executed by a computer, processor, or hardware, the method described herein is implemented. In addition, when a general-purpose computer accesses the code for implementing the method shown herein, the execution of the code converts the general-purpose computer into a dedicated computer for executing the method shown herein.

[0229] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements all fall within the scope of the present invention to be protected.

Claims

1. A method for dispatching a power grid with a self-provided power supply peak in a demand-side corresponding mode, characterized in that: The following steps are involved: Analyze the feasibility of grid-connected operation of self-provided power supply and establish the operation cost model of typical self-provided power supply, including: self-provided diesel generator operation cost model, self-owned energy storage operation cost model and trigeneration dispatch cost model; Setting up a market mechanism for the peak of self-provided power supply under the demand-side response mode, and establishing a Bayesian quotation model for self-provided power supply users based on the operation cost model of the typical self-provided power supply; The goal is to minimize the grid operation cost, and MATLAB is used to solve the Bayesian quotation model of the self-provided power user to calculate the optimal compensation electricity price.

2. The grid dispatching method for self-provided power supply peak in demand side corresponding mode according to claim 1 is characterized in that: The operating cost model of the self-provided diesel generator is: In the formula, C dg is the unit time cost of self-provided diesel generator, P dg Indicates the self-provided diesel power generation, a dg 、b dg 、c dg and d dg All are operating constants of self-contained power diesel generators.

3. The grid dispatching method for self-provided power supply peak in demand side corresponding mode according to claim 2 is characterized in that: The self-owned energy storage operation cost model is: C s =a s P s / or d Where P s is the energy storage output power, η d Represents the discharge efficiency of electrochemical energy storage, C s is the unit time cost of dispatching energy storage, α s Represents the unit capacity cost.

4. The grid dispatching method for self-provided power supply peak in demand side corresponding mode according to claim 3 is characterized in that: The trigeneration scheduling cost model is: In the formula, C tr is the trigeneration dispatching cost, P tr represents the gas turbine output power, a tr 、b tr and c tr is the trigeneration operation constant.

5. The grid dispatching method for self-provided power supply peak in demand side corresponding mode according to claim 4 is characterized in that: The Bayesian quotation model of the self-provided power supply user is: Q(P sb )=cop F(P)=kC(P)+b Where F(P) represents the quotation curve, C(P) represents the cost curve, P represents the declared capacity, k and b are the quotation parameters; Q is the unit quotation with respect to the declared capacity P sb In order to balance the power of the power grid in real time, the model needs to introduce power generation equipment that can balance the power, which can be the main power grid; mcp t * represents the clearing electricity price at time t on the day, represents the average of the power grid clearing price at the same time t in the previous ten days, σ 2 (mcp t ) represents the variance of the clearing electricity price at the same time t in the previous ten days. 2 ) indicates that today's clearing electricity price follows a normal distribution with μ as the central value and σ 2 is the variance; P Lt represents the total grid load at time t; represents the dispatch capacity forecast of the self-provided power supply at time t on the day, P L Represents the total load of the power grid, P z Indicates the response capacity of the self-contained power supply. It represents the forecast of total load at time t of the day; Represents the linear fit P L and P z The forecast of total load at time t on the day is P z Bring in your own power supply to generate power; E xi represents the expected benefit of self-provided power user i in the demand-side response mode, T is the total dispatch time; f mcp and They represent the probability distribution of clearing electricity price and the probability distribution of total load at time t respectively; m i (k,b)≤0 is the restriction condition for user i.

6. The grid dispatching method for self-provided power supply peak in demand side corresponding mode according to claim 5 is characterized in that: The specific process of calculating the optimal compensation electricity price is as follows: The operating cost of the power system considering the self-provided power supply is: Where D x is the total grid operation cost during peak hours under the demand-side response mode; C ht (P ht ) and C zt (P zt ) are the unit time operation costs of the thermal power units of the power grid and the self-provided power supply at time t respectively; The unit time operation cost of thermal power units in the power grid is: In the formula, C h (P h ) is the unit time cost of dispatching thermal power units, P h The power generated by the thermal power unit, a h , and are the operating constants of thermal power units. The unit time operating cost of the self-provided power supply is: C z (P z )=cop*P z In the formula, C z (P z ) is the unit time dispatching cost of self-provided power supply, cop is the unit compensation price of self-provided power supply, P z Generate power for your own power supply. The optimization problem is expressed as: If only the equality constraints are considered, the Lagrangian function for scheduling optimization is: Where P Lt is the total load of the power grid at time t, λ t are the T Lagrangian operators introduced; in order to minimize the power grid operation cost, then: If the self-provided power supply does not reach the maximum value in all time periods, it means that the unit compensation price of the self-provided power supply is high, and reducing the compensation price can achieve the same peak effect; there is at least one period when the self-provided power supply dispatch power reaches the total declared capacity; suppose the self-provided power supply full-time period is the set S = {1,2,…s}, then: In the formula is the derivative of the Lagrangian function to the power of the thermal power unit, where is the derivative of the Lagrangian function to the power of the self-provided power supply when the self-provided power supply is not fully generated, where is the derivative of the Lagrangian function of the self-provided power supply when the self-provided power supply is fully generated, s is the number of full-generation time periods, where is the derivative of the Lagrangian function with respect to the Lagrangian factor, which is also the equality constraint. Lt is the load power at time t; Among them, formula c means that the maximum power of the self-provided power supply is used for scheduling during these s time periods, and the output power of the self-provided power supply is the same during these s time periods; and there is a functional relationship between the unit compensation electricity price and the maximum response capacity.

7. The grid dispatching method for self-provided power supply peak in demand side corresponding mode according to claim 5, characterized in that: The constraints for solving the Bayesian quotation model for self-provided power users using MATLAB include: P dgmin ≤P dg ≤P dgmax P smin ≤P s ≤P smax 0.1SOC max ≤SOC t ≤0.9SOC max P.S e η e P.S tr P.S R (1-η e )P tr P.S ht η h P.S R P trmin <P tr <P trmax P emin <P e <P emax g(P ht ,P zt )=0 Where P dgmin and P dgmax They represent the minimum and maximum power output of the self-provided diesel generator respectively; Gd max Indicates the maximum climbing rate; P smin , P smax They represent the minimum and maximum values ​​allowed for energy storage output respectively; SOC0 is the state of charge at the beginning of scheduling, SOC max is the maximum state of charge of the energy storage device, SOC t is the state of charge at time t; C tr is the trigeneration dispatching cost, P tr Indicates the gas turbine output power; P e represents the power generation of the gas turbine, η e Indicates the efficiency of the gas turbine in generating electrical power; P R is the power generated by the waste heat boiler, P ht is the sum of the power generated by the waste heat boiler converted into cooling and heating power, η h is the conversion efficiency; P cool and P heat Represent the power required for cooling load and heating load respectively, η cool and η heat Describe the efficiency of cooling and heating equipment respectively; η g represents the ratio of gas turbine input to generator, α represents the adjustable range of equivalent heat load; P trmin and P trmax They represent the minimum and maximum power output of the gas turbine, P emin and P emax Respectively represent the minimum and maximum power limits of the generator set output; P i is the injected power of node i, g(P ht ,P zt ) is the power system flow calculation algorithm, and 0 indicates power balance.

8. A power grid dispatching system for self-provided power peak in demand side corresponding mode, characterized in that: include: Cost model building module: Analyze the feasibility of grid-connected operation of self-provided power supply and establish the operation cost model of typical self-provided power supply, including: self-provided diesel generator operation cost model, self-owned energy storage operation cost model and trigeneration dispatch cost model; The quotation model building module is used to set the market mechanism of the self-provided power supply peak under the demand-side response mode, and to establish a Bayesian quotation model for self-provided power supply users based on the operation cost model of the typical self-provided power supply; And, the model solving module: takes the minimization of the grid operation cost as the goal, and uses MATLAB to solve the Bayesian quotation model of the self-provided power supply user to calculate the optimal compensation electricity price.

9. A computer storage medium storing a readable program, characterized in that: When the program is running, it can execute the power grid dispatching method for the self-provided power supply peak in the demand side corresponding mode described in any one of claims 1-7.

10. An electronic device, characterized in that: include: A processor, a memory, a communication interface and a communication bus, wherein the processor, the memory and the communication interface communicate with each other via the communication bus; The memory is used to store at least one executable instruction, and the executable instruction enables the processor to perform operations corresponding to a power grid scheduling method for a self-provided power supply peak in a demand side corresponding mode as described in any one of claims 1-7.

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