Power system inertia and frequency modulation optimization compensation and allocation method and system

Abstract

The invention relates to the technical field of safe and stable operation of a power system, and discloses a power system inertia and frequency modulation optimization compensation and allocation method and system, and the method comprises the steps: evaluating the inertia and primary frequency modulation demand vacancy of the system according to a day-ahead power generation plan result; calculating the inertia provided by the conventional unit and the unit compensation cost of primary frequency modulation, and determining the added conventional unit and the compensation price; and the inertia and the primary frequency modulation service provided by the increased unit are compensated, and cost allocation is carried out. The safety and stability of a power grid are improved, and the frequency stability under the condition of high permeability of new energy is ensured. The compensation mechanism is reasonable, the conventional unit is stimulated to provide auxiliary services, the fair burden of the user and the new energy unit is realized through the cost allocation mechanism, and the economic fairness and the system economy are enhanced.

Description

Technical Field

[0001] The present invention relates to the technical field of safe and stable operation of power systems, and in particular to a method and system for optimizing compensation and sharing of inertia and frequency regulation of power systems. Background Art

[0002] Adapt to the needs of high-proportion new energy access system, and smooth out the disturbances caused by intermittent and volatile new energy on the operation of the power system. At first, when the penetration rate of new energy in the system was not high, the supply of rotational inertia and primary frequency regulation was sufficient, and it was considered that they were incidental products when the synchronous generator set provided electric energy; however, when the penetration rate of new energy reached a certain level, rotational inertia and primary frequency regulation will gradually become scarce resources in the system, and the startup method that only considers the balance of power supply and demand may be difficult to meet the system's rotational inertia demand. In this case, my country has already made corresponding compensation for the equipment that provides rotational inertia and primary frequency regulation in several provinces where a batch of spot pilots are in operation, so as to maintain the incentive for investment and operation and maintenance of synchronous resources; however, as the level of new energy grid connection continues to increase, the price of electricity gradually decreases. Relying solely on compensation in the electricity market can only guarantee the cost recovery of synchronous resources, and the profit space is not clear. It is difficult to form a benign incentive signal for the investment and operation and maintenance of synchronous inertia and primary frequency regulation resources, which indirectly affects the safe and stable operation of the system. Therefore, it is necessary to study the acquisition and compensation of auxiliary services for inertia and primary frequency regulation in the power system. Summary of the invention

[0003] In view of the above-mentioned problems, the present invention is proposed.

[0004] Therefore, the technical problems solved by the present invention are: insufficient inertia and primary frequency regulation resources, unreasonable compensation and unfair cost sharing in a power grid with high new energy penetration rate.

[0005] In order to solve the above technical problems, the present invention provides the following technical solutions: a method for optimizing compensation and allocation of inertia and frequency regulation of a power system, comprising:

[0006] Based on the day-ahead power generation plan, the system inertia and primary frequency regulation demand shortfall are evaluated;

[0007] Calculate the unit compensation cost of conventional units providing inertia and primary frequency regulation, and determine the additional conventional units and compensation prices;

[0008] Compensation will be made for the inertia and primary frequency regulation services provided by the additional units, and the costs will be shared.

[0009] As a preferred scheme of the power system inertia and frequency regulation optimization compensation and allocation method described in the present invention, wherein: evaluating the system inertia and primary frequency regulation demand shortfall includes calculating the minimum inertia demand, calculating the minimum primary frequency regulation capacity demand and calculating the inertia and primary frequency regulation capacity shortfall.

[0010] As a preferred solution of the power system inertia and frequency regulation optimization compensation and allocation method described in the present invention, wherein: the calculation of the minimum inertia requirement includes the minimum inertia considering the frequency change rate constraint, the minimum inertia considering the frequency minimum point constraint, and the minimum inertia considering the frequency change rate and the frequency minimum point constraint comprehensively;

[0011] The minimum inertia considering the frequency change rate constraint includes calculating the minimum inertia required in each time period based on the power disturbance, frequency change rate limit and rated frequency of the system;

[0012] The minimum inertia considering the frequency minimum point constraint includes calculating the minimum inertia when considering the frequency minimum point through the rotor motion equation during the frequency dynamic change process. Considering the system frequency deviation and frequency modulation delay, ensure that the change of the frequency minimum point does not exceed the maximum deviation set by the system;

[0013] The minimum inertia that comprehensively considers the frequency change rate and the frequency minimum point constraints includes combining the frequency change rate and the frequency minimum point constraints to derive the minimum inertia requirement for the system.

[0014] As a preferred solution of the power system inertia and frequency regulation optimization compensation and allocation method described in the present invention, wherein: the calculation of the minimum primary frequency regulation capacity requirement includes, based on the frequency recovery requirements of the system, calculating the minimum primary frequency regulation capacity required by the system;

[0015] Calculating the inertia and primary frequency regulation capacity shortage includes comparing the inertia provided by the started units in the actual power generation plan with the calculated minimum inertia requirement to obtain the inertia shortage of the system; and comparing the primary frequency regulation capacity provided by the started units with the calculated minimum primary frequency regulation requirement to obtain the primary frequency regulation capacity shortage.

[0016] As a preferred solution of the power system inertia and frequency regulation optimization compensation and allocation method described in the present invention, the calculation of the unit compensation cost of the inertia and primary frequency regulation provided by the conventional unit includes converting the unit compensation cost of the inertia and primary frequency regulation of the conventional unit according to the minimum power generation cost of the conventional unit, and the formula is expressed as follows:

[0017]

[0018] in, represents the inertia and primary frequency regulation unit compensation cost of conventional unit i, ρ g,i,min represents the minimum power generation cost of conventional unit i; P g,i,max Indicates the upper limit of active power of conventional unit i, P g,i,min Indicates the lower limit of active power of conventional unit i; H i represents the inertia time constant of conventional unit i, and ΔT represents the duration of a time period.

[0019] As a preferred solution of the power system inertia and frequency regulation optimization compensation and allocation method described in the present invention, the determination of the additional conventional units and the compensation price includes designing the optimization objective function and defining the constraint conditions;

[0020] Optimizing the objective function includes establishing an optimization function with the goal of minimizing the operating cost of the system;

[0021] The constraints include inertia demand constraint, primary frequency regulation capacity demand constraint and minimum continuous start and stop time constraint of the unit;

[0022] The operating costs of the system include the startup cost of the unit, the unit compensation cost of inertia and primary frequency regulation, and the power generation operating cost.

[0023] As a preferred solution of the power system inertia and frequency regulation optimization compensation and allocation method of the present invention, wherein: the compensation for the inertia and primary frequency regulation service provided by the additional units includes calculating the daily compensation fee, calculating the total fee and the fee allocation, and then making a settlement payment;

[0024] The calculation of daily compensation costs includes, based on the marginal compensation price, calculating the daily compensation costs for each additional unit providing inertia and primary frequency regulation services;

[0025] The calculation of the total cost includes summing up the daily compensation costs of all the additional units to obtain the system inertia and the total cost of primary frequency regulation auxiliary services;

[0026] The cost sharing includes allocating the total cost to the grid users and the new energy units in proportion to ensure that all parties reasonably bear the system auxiliary service costs;

[0027] Settlement payments include compensation for additional units and collection of corresponding fees from users and new energy units to ensure the stability and economic operation of the power grid.

[0028] A power system inertia and frequency regulation optimization compensation and allocation system, wherein:

[0029] The inertia and primary frequency regulation demand assessment module assesses the system's inertia and primary frequency regulation demand shortfall based on the day-ahead power generation plan results;

[0030] The compensation cost calculation module calculates the unit compensation cost of the conventional units providing inertia and primary frequency regulation, and determines the additional conventional units and compensation prices;

[0031] The cost sharing and settlement module compensates for the inertia and primary frequency regulation services provided by the additional units and shares the costs.

[0032] A computer device comprises: a memory and a processor; the memory stores a computer program, wherein the processor implements the steps of any one of the methods of the present invention when executing the computer program.

[0033] A computer-readable storage medium stores a computer program, wherein the computer program, when executed by a processor, implements the steps of any one of the methods of the present invention.

[0034] Beneficial effects of the invention: The power system inertia and frequency regulation optimization compensation and sharing method provided by the invention improves the safety and stability of the power grid by optimizing the acquisition and compensation of inertia and primary frequency regulation services, and ensures frequency stability under the condition of high penetration of new energy. Its compensation mechanism is reasonable, which encourages conventional units to provide auxiliary services, and realizes fair burden of users and new energy units through the cost sharing mechanism, thus enhancing economic fairness and system economy. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0036] Figure 1 An overall flow chart of a method for optimizing compensation and sharing of inertia and frequency regulation of a power system provided in the first embodiment of the present invention. DETAILED DESCRIPTION

[0037] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in the art without creative work should fall within the scope of protection of the present invention.

[0038] Example 1, reference Figure 1 , which is an embodiment of the present invention, provides a method for optimizing compensation and allocation of inertia and frequency regulation of a power system, comprising:

[0039] S1: Based on the day-ahead power generation plan, evaluate the system inertia and primary frequency regulation demand shortfall.

[0040] Accurate and effective evaluation of system inertia and primary frequency regulation requirements is the basis for clarifying the system inertia and primary frequency regulation shortfalls in each period. After a system disturbance occurs, the requirements for frequency safety form three indicators: frequency change rate, lowest frequency, and quasi-steady-state frequency. Among them, the frequency change rate and lowest frequency are related to the system inertia, and the lowest frequency and quasi-steady-state frequency are related to the system primary frequency regulation. Ignoring the influence of load damping, the minimum inertia and primary frequency regulation requirements that comprehensively consider the frequency change rate and frequency lowest point constraints in each period are obtained. The steps for calculating the inertia and primary frequency regulation shortfall are as follows:

[0041] Step 1-1, calculate the minimum inertia requirement of the system;

[0042] (1) Minimum inertia considering frequency change rate constraint

[0043]

[0044] Among them, I min,t,RoCaF is the minimum inertia of the system considering the frequency change rate constraint in the ι period, MWs; T is the total number of periods, 24 or 96; f0 is the rated frequency of the system; RoCoF max Specifies the maximum frequency variation limit allowed for the system; P l oss ,t is the power disturbance of the system during period t.

[0045] (2) Consider the minimum inertia of the lowest frequency point constraint

[0046] The dynamic change process of system frequency can be described by the following rotor motion equation:

[0047]

[0048] in, is the primary frequency regulation capacity of the system in period t; I sys,t is the inertia of the system in period t; Δf is the system frequency deviation.

[0049] The formula (2) can be written as:

[0050]

[0051] Assumption i * is the moment when the frequency reaches the lowest point. Integrate both sides of equation (3) to obtain the change expression when the frequency reaches the lowest point:

[0052]

[0053] Among them, Δf(t * ) is the change value of the frequency reaching the lowest point; t * is the moment of lowest frequency; T del is the unit's primary frequency modulation delay; T r Amp is the complete response time of the unit's primary frequency regulation.

[0054] The change value of the frequency reaching the lowest point satisfies:

[0055] |Δf(t * )|≤Δf max (5)

[0056] Where Δf mx is the maximum frequency deviation specified by the system. Since the unit cannot respond immediately to the frequency adjustment, the lowest frequency point will fall on ι∈[T del , T del +T romp ]middle.

[0057] Therefore, t * satisfy:

[0058]

[0059] Substituting formula (6) into formula (4), we get:

[0060]

[0061] Substituting formula (7) into formula (5) and making equivalent changes, we get:

[0062]

[0063] Among them, I t，nαir To consider the inertia of the system at the lowest frequency point during the t period. The quasi-steady-state frequency constraint is:

[0064]

[0065] Combining equations (8) and (9), it can be seen that the minimum inertia of the system considering the lowest point constraint has a negative correlation with the primary frequency regulation capacity of the system, I m in, t, nadir with The increase of Take the minimum value, that is When min，t，nadir It has a maximum value, which is the minimum inertia requirement for the system considering the lowest point constraint.

[0066] Then the system considers the minimum inertia of the frequency minimum point constraint in period t:

[0067]

[0068] Among them, I m int, nadr is the minimum inertia of the constraint system in period t considering the lowest frequency point.

[0069] Taking into account the frequency change rate constraint and the frequency minimum point constraint, the minimum inertia requirement of the system in period t is obtained:

[0070] I sys,t,min =maxI min,t,RoCoF ,I min,t,nacir (11)

[0071] Among them, I sys,t,min is the minimum inertia requirement of the system in period ι.

[0072] Step 1-2: Calculate the minimum primary frequency modulation capacity requirement of the system. After a large disturbance occurs, the system frequency needs to be restored to a quasi-steady state, so at least the quasi-steady state constraint needs to be met. Then the minimum primary frequency modulation capacity requirement of the system is:

[0073]

[0074] in, is the minimum frequency regulation capacity requirement of the system in period t.

[0075] Steps 1-3: Calculate system inertia and primary frequency regulation capacity shortfall.

[0076] The inertia and primary frequency regulation capacity shortages are as follows:

[0077] 1) Inertia shortage:

[0078] I sys,t,vac =I sys,t,min -I 1,t ,t=1,2,…,T(13)

[0079] Among them, I sys,t,vac is the inertia shortage of the system in period t; I1,t represents the inertia provided by the units started in period t obtained according to the day-ahead power generation plan.

[0080] 2) Primary frequency modulation capacity shortage:

[0081]

[0082] in, The frequency regulation capacity shortage of the system in period t; It is the primary frequency regulation capacity provided by the units started during period t obtained according to the day-ahead power generation plan.

[0083] Furthermore, by calculating the minimum inertia requirement and primary frequency regulation requirement of the system, the present invention provides the power system with basic data for maintaining frequency stability, ensuring the safety and responsiveness of the system under different disturbance scenarios. In an environment where renewable energy power generation fluctuates greatly, this dynamic and real-time demand assessment can effectively cope with the frequency deviation caused by load fluctuations. By calculating indicators such as the frequency change rate, the lowest point frequency, and the quasi-steady-state frequency, it is possible to accurately guide the grid dispatching and scientifically formulate plans for adding units, thereby improving the economy and operation efficiency of the system. Traditional methods often rely on static estimates and are difficult to accurately match real-time demand, while the method of the present invention provides data support for adaptive adjustment of load and frequency. At the same time, this assessment based on inertia and frequency regulation requirements provides a scientific basis for the sharing of compensation costs, especially under high penetration rates of renewable energy, which significantly enhances the resilience and reliability of the grid to large disturbances.

[0084] S2: Calculate the unit compensation cost of conventional units providing inertia and primary frequency regulation, and determine the additional conventional units and compensation prices.

[0085] The unit compensation cost of inertia and primary frequency regulation of conventional units is converted according to their minimum power generation cost, because conventional units can provide corresponding inertia and primary frequency regulation when operating at minimum power generation output. The minimum output cost generated by conventional units in a certain period of time is the cost required for the unit to provide inertia and primary frequency regulation. After dividing by the inertia, the unit compensation cost of inertia and primary frequency regulation of the unit is obtained. The calculation method is as follows:

[0086]

[0087] in, is the inertia and primary frequency regulation unit compensation cost of conventional unit i, yuan / MWs; ρ g,i,min represents the minimum power generation cost of conventional unit i; P g,i,max , P g,i,min are respectively the upper and lower limits of active power of conventional unit i; H i It represents the inertia time constant of conventional unit i, s; ΔT is the duration of a time period.

[0088] Furthermore, by reasonably calculating the unit compensation cost of conventional units providing inertia and primary frequency regulation, the economy and fairness of the system can be achieved while efficiently obtaining auxiliary services. The compensation calculation based on the minimum power generation cost ensures that the power grid meets the inertia and primary frequency regulation requirements at the lowest cost, effectively reducing the system operation cost. At the same time, the compensation mechanism guarantees the reasonable benefits of conventional units when providing auxiliary services, encourages more units to participate, and improves the stability of the system frequency. Sorting the unit compensation cost allows the system to give priority to the increase of units with lower compensation costs, avoiding the non-optimal configuration in the traditional method and improving the efficiency of obtaining auxiliary services. In addition, the reasonable compensation price mechanism achieves fair distribution, avoids unreasonable compensation, enhances the system's adaptability to fluctuations in new energy, and enables the power grid to maintain stable and reliable operation when the proportion of new energy access is high.

[0089] S3: Compensate for the inertia and primary frequency regulation services provided by the additional units, and share the costs.

[0090] Methods for optimizing the acquisition of inertia and primary frequency regulation auxiliary services and determining the conventional units that need to be added and the inertia and primary frequency regulation compensation prices include:

[0091] Objective function:

[0092]

[0093] Among them, Ω g2,t Indicates the number of remaining conventional units in period t; u i , t is the 0-1 start-stop state variable of the conventional unit i in period t, 1 represents start-up and 0 represents shutdown; is the startup cost of conventional unit i.

[0094] Constraints:

[0095] (1) Inertia requirement constraint

[0096]

[0097] (2) Primary frequency regulation capacity demand constraints

[0098]

[0099] in, Reserve capacity for primary frequency regulation of conventional unit i.

[0100] (3) Minimum continuous start and stop time constraints for units

[0101]

[0102] Among them, T i ,t,wp,Ti ,t,dm are the continuous start and stop times of conventional unit i in period t respectively; T i ,up,T i,dn are the minimum start and stop time requirements of conventional unit i. Inertia and primary frequency regulation compensation price. For the newly started units, sort the inertia and primary frequency regulation unit compensation costs of the units from low to high, and find the marginal unit, whose unit compensation cost is the compensation price.

[0103] The method of providing inertia and primary frequency regulation auxiliary service compensation for additional units and sharing the inertia and primary frequency regulation auxiliary service costs between new energy and users includes:

[0104] 1) Compensation for the inertia of additional units and primary frequency regulation auxiliary services:

[0105]

[0106] in, The daily compensation cost for the inertia and primary frequency regulation auxiliary service of unit i; is the compensation price of inertia and primary frequency modulation during period t; Ω g3,t is the set of newly started units obtained during period t. 2) Inertia and primary frequency regulation auxiliary service cost allocation:

[0107] Inertia / total cost of primary frequency regulation auxiliary service C IPFR for:

[0108]

[0109] The total fee for inertia / primary frequency regulation auxiliary service shall be shared by users and new energy sources. Because the electricity cost calculated by the result of the day-ahead power generation plan in step 1 is the actual fee that users have to pay, and there is generally a formal clearing afterwards, that is, based on the startup mode of the day-ahead power generation plan in step 1 and the newly added startup mode obtained in step 3, the formal clearing optimization calculation of the day-ahead electricity energy is performed. At this time, the electricity cost of the stop-clearing will be obtained, but the electricity cost of the stop-clearing will be lower than the electricity cost that users actually have to pay. On the one hand, it is because the newly added upgrades have squeezed the power generation space of the original startup units, resulting in a lower marginal compensation price. On the other hand, it only settles the startup units in step 1, excluding the newly added 30 units. If the settlement is made according to the stop-clearing results, the user obviously pays less, so the difference between them is also paid by the user, which is part of the total cost sharing of inertia / primary frequency regulation auxiliary services.

[0110] The total cost of inertia / primary frequency regulation auxiliary service is shared by users and new energy sources as follows:

[0111]

[0112] in, The costs are shared by users and new energy respectively.

[0113] Inertia / primary frequency regulation auxiliary service costs shared by users:

[0114]

[0115] in, The electric energy cost calculated from the day-ahead power generation plan result in step 1; The electricity energy cost obtained for formal settlement.

[0116] Inertia and primary frequency regulation ancillary service costs caused by renewable energy generation:

[0117]

[0118] The user share is allocated according to the actual electricity consumption ratio of each household. The calculation formula is:

[0119]

[0120] Among them, C load,i is the shared cost of user i; P l oad,j is the electricity consumption of user i; N l oad is the total number of users.

[0121] The inertia and primary frequency regulation auxiliary service costs caused by renewable energy power generation shall be borne by renewable energy and can be apportioned according to the proportion of their electricity consumption. The formula is:

[0122]

[0123] Among them, C n e,i is the shared cost of new energy unit i; N n e is the total number of new energy units; P n e,i,t is the active power output of new energy unit i in period t.

[0124] Furthermore, by reasonably compensating and sharing the costs of the inertia and primary frequency regulation services of the additional units, the power system can ensure the economy and operational safety of auxiliary services in a fair and efficient manner. First, the compensation cost of the additional units is based on the marginal cost principle, and the marginal unit with the lowest unit compensation cost is selected as the compensation price, so that the system can obtain the required inertia and primary frequency regulation services at the optimal cost. Secondly, the reasonable sharing of costs balances the system burden and avoids excessive cost pressure on one side by allowing users and new energy units to jointly bear the costs of inertia and primary frequency regulation. Users share costs based on the actual electricity consumption ratio, while new energy units share the ancillary service costs according to the power generation ratio, thereby ensuring fair and reasonable cost allocation. In addition, through the formal clearing calculation method, unreasonable cost settlement is avoided, and the additional costs incurred by users due to the additional units are effectively reduced. This step design ensures that the power system maintains economic efficiency while also encouraging conventional units to actively participate in system frequency regulation, thereby improving the system's responsiveness to frequency fluctuations and the overall stability of operation.

[0125] Embodiment 2 is an embodiment of the present invention, which provides a power system inertia and frequency regulation optimization compensation and allocation system, including:

[0126] The inertia and primary frequency regulation demand assessment module assesses the system's inertia and primary frequency regulation demand shortfall based on the day-ahead power generation plan results.

[0127] The compensation cost calculation module calculates the unit compensation cost of the conventional units providing inertia and primary frequency regulation, and determines the additional conventional units and compensation prices.

[0128] The cost sharing and settlement module compensates for the inertia and primary frequency regulation services provided by the additional units and shares the costs.

[0129] Embodiment 3, an embodiment of the present invention, is different from the first two embodiments in that:

[0130] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc., which can store program codes.

[0131] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in conjunction with such instruction execution systems, devices or apparatuses. For the purposes of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in conjunction with such instruction execution systems, devices or apparatuses.

[0132] More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection with one or more wires (electronic device), a portable computer disk case (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be a paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, deciphering or, if necessary, processing in another suitable manner, and then stored in a computer memory.

[0133] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, a plurality of steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0134] Example 4, select a new energy high penetration power grid scenario for experiment, whose system demand is dynamic and randomly fluctuates to simulate actual operation. According to the method of the present invention, first, the output of conventional units in the system and the expected output of new energy are obtained according to the day-ahead power generation plan, and the inertia and primary frequency regulation shortage in the current period are analyzed. In order to reasonably evaluate the inertia demand, the frequency change rate, the lowest frequency point and other indicators of the system under different disturbance conditions are considered, and the minimum inertia and primary frequency regulation demand are calculated according to the formula.

[0135] Specifically, this embodiment includes three core steps: evaluating the inertia and primary frequency regulation shortage, calculating the compensation cost of additional units, optimizing the apportionment of costs and compensating for them. In the evaluation stage, the test period is selected as 24 hours (divided into 96 sub-periods, each sub-period is 15 minutes). Collect the expected power generation data of wind energy, solar energy and other new energy sources, and combine them with the system load forecast to judge the impact of the intermittent output of new energy on the power grid under the high penetration scenario, so as to determine the inertia and primary frequency regulation demand shortage of the system in each time period. Subsequently, according to the demand shortage, the unit compensation cost is calculated based on the minimum power generation cost of each unit, and the system gradually selects additional units in order of compensation cost from low to high until the inertia and primary frequency regulation requirements of the system are met. The optimization calculation adopts a mixed integer linear programming algorithm to minimize the total operating cost.

[0136] In calculating the compensation price of additional units, the unit with the lowest compensation cost of inertia and primary frequency regulation is selected as the marginal unit, and its unit compensation cost is used as the compensation price of the entire system to ensure the optimal cost allocation plan. After completing the unit increase plan, the cost of inertia and primary frequency regulation services provided by the additional units is apportioned. The cost is apportioned in proportion to the actual power consumption of the user and the power generation of the new energy units to ensure that the cost is fair and reasonable. During the simulation process, the inertia and primary frequency regulation values, compensation costs, and apportioned costs provided by each unit are recorded for subsequent analysis.

[0137]

[0138]

[0139] It can be seen from the table data that the method of the present invention shows obvious advantages in evaluating system inertia and primary frequency regulation requirements, determining compensation prices and allocating costs. First, the calculation of the inertia demand shortfall and the primary frequency regulation demand shortfall is based on the system frequency change and power disturbance, reflecting the real demand for inertia and primary frequency regulation services provided by different units at their respective minimum outputs. This method can effectively ensure the stability of system frequency under large disturbances, while traditional methods usually rely only on static demand estimates, and it is difficult to fully consider the impact of real-time disturbances, so it is easy to cause excessive increase in units and increase system costs.

[0140] In terms of unit compensation cost calculation, the present invention obtains a reasonable unit compensation price based on the minimum power generation cost of each unit, and selects the unit with the lowest unit compensation cost as the marginal unit to ensure that the cost-effectiveness of the additional unit is optimal. It can be seen from the table that the unit compensation cost increases from low to high, and after selecting the unit compensation cost of the marginal unit (i.e., unit F) as the compensation price, the total cost of the additional unit is significantly lower than the cost of all units calculated according to the highest unit compensation cost in the traditional method (such as the cost calculated according to the compensation cost of unit D will reach nearly 35,000 yuan). Therefore, the optimization method of unit compensation cost sorting not only meets the system requirements, but also reduces the compensation cost, reflecting the innovative advantages of the present invention in terms of economy.

[0141] In addition, the cost sharing mechanism has the advantage of being fairer than traditional methods. By sharing the cost of adding additional units to grid users and new energy units, the present invention shares the cost of inertia and primary frequency regulation services according to the proportion of user power consumption and new energy power generation, thus avoiding the centralization of costs. As can be seen from the table, users and new energy units share the same cost, with a total cost of 32,900 yuan, while traditional methods usually directly share all of the cost with grid users, which may cause users to be overburdened. The cost sharing mechanism of the present invention not only ensures the rationality of the user burden, but also enhances the enthusiasm of new energy units to participate in grid operation.

[0142] Finally, the optimization method based on the mixed integer linear programming algorithm effectively improves the system operation efficiency and stability. In practical applications, the optimization method of the present invention can quickly determine the combination of additional units and the compensation price within 30 seconds, ensuring the real-time and accuracy of the calculation process, which is significantly better than the manual selection and static estimation in the prior art. In addition, the algorithm is suitable for various types of power grid dispatching systems and can be efficiently applied in complex power grid scenarios to further improve the system's automation management level and economy. Through the method of the present invention, not only the cost of auxiliary services is reduced, but also the adaptability and stability of the power grid are enhanced, which is particularly prominent in the context of a high proportion of new energy access.

[0143] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A method for optimizing compensation and allocation of inertia and frequency regulation of a power system, characterized in that: include: Based on the day-ahead power generation plan, the system inertia and primary frequency regulation demand shortfall are evaluated; Calculate the unit compensation cost of conventional units providing inertia and primary frequency regulation, and determine the additional conventional units and compensation prices; Compensation will be made for the inertia and primary frequency regulation services provided by the additional units, and the costs will be shared.

2. The power system inertia and frequency modulation optimization compensation and allocation method according to claim 1, characterized in that: Evaluating the inertia and primary frequency regulation demand shortfall of the system includes calculating the minimum inertia demand, calculating the minimum primary frequency regulation capacity demand, and calculating the inertia and primary frequency regulation capacity shortfall.

3. The power system inertia and frequency modulation optimization compensation and allocation method according to claim 2, characterized in that: The calculation of the minimum inertia requirement includes the minimum inertia considering the frequency change rate constraint, the minimum inertia considering the frequency minimum point constraint, and the minimum inertia considering both the frequency change rate and the frequency minimum point constraint; The minimum inertia considering the frequency change rate constraint includes calculating the minimum inertia required in each time period based on the power disturbance, frequency change rate limit and rated frequency of the system; The minimum inertia considering the frequency minimum point constraint includes calculating the minimum inertia when considering the frequency minimum point through the rotor motion equation during the frequency dynamic change process. Considering the system frequency deviation and frequency modulation delay, ensure that the change of the frequency minimum point does not exceed the maximum deviation set by the system; The minimum inertia that comprehensively considers the frequency change rate and the frequency minimum point constraints includes combining the frequency change rate and the frequency minimum point constraints to derive the minimum inertia requirement for the system.

4. The power system inertia and frequency modulation optimization compensation and allocation method according to claim 3, characterized in that: The calculating of the minimum primary frequency modulation capacity requirement includes calculating the minimum primary frequency modulation capacity required by the system based on the frequency recovery requirement of the system; Calculating the inertia and primary frequency regulation capacity shortage includes comparing the inertia provided by the started units in the actual power generation plan with the calculated minimum inertia requirement to obtain the inertia shortage of the system; and comparing the primary frequency regulation capacity provided by the started units with the calculated minimum primary frequency regulation requirement to obtain the primary frequency regulation capacity shortage.

5. The power system inertia and frequency modulation optimization compensation and allocation method according to claim 4, characterized in that: The calculation of the unit compensation cost of the inertia and primary frequency regulation provided by the conventional unit includes converting the unit compensation cost of the inertia and primary frequency regulation of the conventional unit according to the minimum power generation cost of the conventional unit, and the formula is expressed as follows: in, represents the inertia and primary frequency regulation unit compensation cost of conventional unit i, ρ g,i,min represents the minimum power generation cost of conventional unit i; P g,i,max Indicates the upper limit of active power of conventional unit i, P g,i,min Indicates the lower limit of active power of conventional unit i; H i represents the inertia time constant of conventional unit i, and ΔT represents the duration of a time period.

6. The power system inertia and frequency regulation optimization compensation and allocation method according to claim 5, characterized in that: Determining the additional conventional units and compensation prices includes designing the optimization objective function and defining the constraints; Optimizing the objective function includes establishing an optimization function with the goal of minimizing the operating cost of the system; The constraints include inertia demand constraint, primary frequency regulation capacity demand constraint and minimum continuous start and stop time constraint of the unit; The operating costs of the system include the startup cost of the unit, the unit compensation cost of inertia and primary frequency regulation, and the power generation operating cost.

7. The power system inertia and frequency regulation optimization compensation and allocation method according to claim 6, characterized in that: The compensation for the inertia and primary frequency regulation services provided by the additional units includes calculating the daily compensation fee, calculating the total fee and the fee allocation, and then making a settlement payment; The calculation of daily compensation costs includes, based on the marginal compensation price, calculating the daily compensation costs for each additional unit providing inertia and primary frequency regulation services; The calculation of the total cost includes summing up the daily compensation costs of all the additional units to obtain the system inertia and the total cost of primary frequency regulation auxiliary services; The cost sharing This includes allocating the total cost to grid users and renewable energy units in proportion to ensure that all parties bear the system ancillary service costs reasonably; Settlement payments include compensation for additional units and collection of corresponding fees from users and new energy units to ensure the stability and economic operation of the power grid.

8. A power system inertia and frequency modulation optimization compensation and sharing system, characterized by: The inertia and primary frequency regulation demand assessment module assesses the system's inertia and primary frequency regulation demand shortfall based on the day-ahead power generation plan results; The compensation cost calculation module calculates the unit compensation cost of the conventional units providing inertia and primary frequency regulation, and determines the additional conventional units and compensation prices; The cost sharing and settlement module compensates for the inertia and primary frequency regulation services provided by the additional units and shares the costs.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the power system inertia and frequency regulation optimization compensation and allocation method described in any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the power system inertia and frequency regulation optimization compensation and allocation method described in any one of claims 1 to 7 are implemented.

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