Power grid probabilistic electric power and electric quantity balance risk assessment method and system

Abstract

The invention discloses a power grid probabilistic power and electric quantity balance risk assessment method and system, and relates to the technical field of power systems, and the method comprises the steps: employing an affine strategy as an adjustment means for a thermal power generating unit to cope with a wind and light prediction error, and defining the up and down adjustment demands of a power grid and the up and down climbing standby adjustment capability provided by the thermal power generating unit; based on a probability theory, defining a power grid probabilistic power and electric quantity balance risk; and based on a conditional value-at-risk theory, providing load shedding power and power abandoning power risk indexes of the power grid under a certain confidence probability, and performing evaluation. According to the power grid probabilistic power and electric quantity balance risk assessment method provided by the invention, an affine strategy is adopted as an adjustment means for a thermal power generating unit to cope with a wind-solar prediction error; based on a probability theory and a conditional value-at-risk theory, load shedding power and abandoned power risk indexes of the power grid under a certain confidence probability are proposed, and the power and electric quantity balance risk of the power grid under a high-proportion new energy scene can be accurately quantified.

Description

Technical Field

[0001] The present invention relates to the technical field of power systems, and in particular to a method and system for evaluating the risk of probabilistic power and electricity balance in a power grid. Background Art

[0002] Developing new energy is a key path to achieve the goal of "carbon peak and carbon neutrality" and solve problems such as environmental pollution and energy crisis. With the rapid development of new energy technologies, a high proportion of new energy grid connection has become a prominent feature of the new power system. By the end of 2023, my country's wind power and photovoltaic installed capacity will reach 440 million kW and 610 million kW respectively, and the proportion of new energy installed capacity will reach 36%, becoming the second largest power source in my country.

[0003] In the analysis of traditional thermal power-dominated power systems, due to the ample controllable range of thermal power, the time series coupling of operation constraints is often ignored, and each time section is characterized by the upper and lower limits of the unit output; while the variance of the load forecast error is small, and the risk of power imbalance can be controlled by the deterministic reserve rule to be low enough. The structure and operation characteristics of the extremely high proportion of renewable energy power systems are very different from those of traditional systems. The adjustable resources of various links such as source, load, and storage jointly participate in achieving power balance. Its time series coupling characteristics lead to the existence of feasible solutions for power balance at different time sections. Strongly randomly fluctuating wind / solar power sources become the main body of system power, and the operating conditions are complex and changeable, which is difficult to characterize with a small number of typical operating conditions. There is an urgent need to carry out probabilistic characteristics analysis of power balance. The traditional method based on time series simulation relies on the time series operation point for the analysis of power balance. Under uncertain conditions, the operation point is also uncertain, which makes the analysis difficult. It is difficult to effectively solve the above problems by simply increasing the number of simulation scenarios or introducing time-divided probabilistic balance analysis. Therefore, traditional power and electricity balance analysis methods are increasingly unable to meet the analysis needs of time coupling and probabilistic balance in scenarios with increasing wind / solar power penetration rates, and there is an urgent need to re-understand the power and electricity balance problem of the power system. Summary of the invention

[0004] In view of the above-mentioned problems, the present invention is proposed.

[0005] Therefore, the technical problem solved by the present invention is: the current power and electricity balance analysis method does not fully consider the strong uncertainty of extremely high proportion of new energy output, cannot accurately quantify the supply guarantee and power abandonment risks faced by the power system, and does not provide a probabilistic risk assessment indicator that adapts to the high proportion of new energy access and takes into account the strong uncertainty characteristics; it does not consider the high proportion of new energy power balance system scenario, does not take into account the flexible ramping and standby adjustment capabilities of thermal power, and cannot effectively assess the risks brought by the uncertainty of wind and solar output to the system power and electricity balance. Therefore, the present invention proposes a probabilistic power and electricity balance risk assessment indicator for power grids, combines affine factors and flexible ramping and standby capacity of thermal power to define a probabilistic indicator that characterizes the power and electricity balance risk, and based on the conditional risk value theory, proposes the system's load shedding power and power abandonment power risk indicators under a certain confidence probability, so as to accurately quantify the power and electricity balance risk of power grids under high proportion of new energy scenarios, so as to ensure the safe and stable operation of power grids.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions: a method for risk assessment of power balance of power grid based on probability, comprising:

[0007] The affine strategy is used as a means of adjusting the thermal power units to deal with the wind and solar forecast errors, and the up and down regulation requirements of the power grid and the up and down ramp reserve regulation capabilities that the thermal power units can provide are defined;

[0008] Based on probability theory, define the probabilistic power balance risk of the power grid;

[0009] Based on the conditional value at risk theory, risk indicators of load shedding power and power abandonment power under a certain confidence probability are proposed for evaluation.

[0010] As a preferred solution of the probabilistic power balance risk assessment method for power grids described in the present invention, the upper and lower adjustment requirements are expressed as:

[0011]

[0012] in, They represent the prediction errors of wind farm and photovoltaic power station in time period t, represents the total error of wind and solar forecast, represents the participation factor of thermal power units; They are respectively represented as the upward / downward adjustment factors of thermal power unit i in time period t; They represent the upper and lower spinning reserve capacities of thermal power unit i in time period t respectively; It means that the thermal power units are really producing; is the power of thermal power unit i at time t; represents the total error of wind and solar forecast;

[0013] They are respectively represented as the upward and downward regulation requirements of the system.

[0014] As a preferred solution of the method for evaluating the risk of probabilistic power and electricity balance of power grid described in the present invention, the probabilistic power and electricity balance risk of power grid is expressed as:

[0015]

[0016] Among them, γ1 and γ2 represent the load loss and power abandonment probabilities allowed by the system;

[0017] According to the probability balance risk expression of formula (4), the load shedding random variable and the power abandonment random variable can be defined as follows:

[0018]

[0019] in, represents the load shedding random variable, represents the random variable of abandoned power;

[0020] Based on the definition of risk value VaR, under a specific confidence probability, the threshold formula of the random variables of load shedding and power abandonment is expressed as:

[0021]

[0022] in, They represent the load shedding random variable threshold and the power abandonment random variable threshold in time period t respectively.

[0023] As a preferred solution of the method for risk assessment of probabilistic power and electricity balance of power grid described in the present invention, wherein: The physical meaning is to make sure that the reserve dispatch instruction of thermal power is When , the load shedding power that may occur when the system supply and demand is balanced is less than b1, and the minimum value among all b1 is the load shedding power threshold under the confidence probability β1;

[0024] The physical meaning is to make sure that the reserve dispatch instruction of thermal power is When , the power abandonment that may occur when the system supply and demand is balanced is less than b2, and the minimum value among all b2 is the power abandonment threshold under the confidence probability β2.

[0025] As a preferred solution of the probabilistic power balance risk assessment method for power grids described in the present invention, the conditional risk value theory is expressed as:

[0026]

[0027] in, are the risk indicators of load shedding power and wind power abandonment in the system during period t, respectively; is the probability distribution function of the wind and solar forecast error.

[0028] As a preferred solution of the method for risk assessment of probabilistic power and electricity balance of power grid described in the present invention, wherein: The physical meaning is that the load shedding power exceeds its threshold The conditional expected value of this part of the load shedding power is, The physical meaning is that the power abandonment exceeds its threshold The conditional expected value of this part of the abandoned power.

[0029] As a preferred solution of the method for risk assessment of power balance of power grid according to the present invention, when minimizing When, also obtained a Introducing helper functions To indicate The definition is as follows:

[0030]

[0031] in,[·] + represents max{·,0};

[0032] Using random variables The sample approximation is:

[0033]

[0034] Another object of the present invention is to provide a probabilistic power and electricity balance risk assessment system for power grids, which can solve the problem of ensuring security and confidentiality of data transmission in existing distribution network operations by constructing a remote secure communication system for distribution network operations, and the problem that using a third-party platform is not conducive to data confidentiality.

[0035] To solve the above technical problems, the present invention provides the following technical solutions: a probabilistic power and electricity balance risk assessment system for a power grid, comprising: a regulation module, a balancing module and an evaluation module; the regulation module is used to adopt an affine strategy as an adjustment means for thermal power units to cope with wind and solar power forecast errors, and define the up and down regulation requirements of the power grid and the up and down climbing standby regulation capabilities that the thermal power units can provide; the balancing module is used to define the probabilistic power and electricity balance risk of the power grid based on probability theory; the evaluation module is used to propose load shedding power and power abandonment power risk indicators of the power grid under a certain confidence probability based on the conditional risk value theory, and conduct evaluation.

[0036] A computer device comprises a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the steps of the above-mentioned method for probabilistic power balance risk assessment of a power grid are implemented.

[0037] A computer-readable storage medium stores a computer program, which, when executed by a processor, implements the steps of the above-mentioned method for risk assessment of probabilistic power balance of electric power grid.

[0038] Beneficial effects of the present invention: The probabilistic power balance risk assessment method for power grids provided by the present invention adopts an affine strategy as a means of adjusting the wind and solar forecast errors of thermal power units, and proposes a method for describing the up and down regulation requirements of the power grid and the up and down ramp standby regulation capabilities that thermal power units can provide;

[0039] Based on probability theory and conditional risk value theory, risk indicators of load shedding power and power abandonment power under certain confidence probabilities are proposed, which can accurately quantify the power balance risk of the power grid under a high proportion of new energy scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] 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.

[0041] Figure 1 An overall flow chart of a method for probabilistic power and electricity balance risk assessment in a power grid provided by an embodiment of the present invention.

[0042] Figure 2 A schematic diagram of power and electricity balance risk of a power grid probabilistic power and electricity balance risk assessment method provided by an embodiment of the present invention.

[0043] Figure 3 An optimized diagram of the ramping spare capacity of each thermal power unit in a method for risk assessment of probabilistic power balance in a power grid provided by an embodiment of the present invention.

[0044] Figure 4 A risk value diagram of load shedding power conditions in each time period of a probabilistic power grid electricity balance risk assessment method provided by an embodiment of the present invention.

[0045] Figure 5 A graph of optimization results of the ramp reserve capacity of each thermal power unit in a method for risk assessment of probabilistic power balance in a power grid provided by an embodiment of the present invention.

[0046] Figure 6A risk value diagram of power abandonment conditions in each time period of a probabilistic power grid electricity balance risk assessment method provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0047] In order to make the above-mentioned objects, features and advantages of the present invention more clearly understood, the following is a detailed description of the present invention in conjunction with the accompanying drawings.

[0048] The specific implementation methods are described in detail, and it is obvious that the described embodiments are part of the embodiments of the present invention, but not all of them. 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.

[0049] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0050] Example 1, reference Figure 1-Figure 2 , which is an embodiment of the present invention, provides a method for risk assessment of power balance of power grid based on probability, including:

[0051] The volatility and uncertainty of high-proportion wind and solar power output in new power systems have a great impact on the power balance, making it difficult to accurately assess the system's risk of new energy power abandonment and supply guarantee. To this end, the present invention proposes a probabilistic power balance risk assessment indicator for power grids. First, a probabilistic indicator that characterizes the power balance risk is defined by combining the affine factor and the flexible ramping reserve capacity of thermal power, and based on the conditional risk value theory, a risk indicator for load shedding power and power abandonment power of the system under a certain confidence probability is proposed.

[0052] Step 1: Use the affine strategy as a means of adjusting the thermal power unit to deal with the wind and solar forecast errors, define the up and down regulation requirements of the power grid and the up and down ramp reserve regulation capabilities that the thermal power unit can provide;

[0053] Step 2: Based on probability theory, define the probabilistic power balance risk of the power grid;

[0054] Step 3: Based on the conditional risk value theory, the risk indicators of load shedding power and power abandonment power of the power grid under a certain confidence probability are proposed.

[0055] The up and down regulation requirements of the power grid and the up and down ramp reserve regulation capabilities that thermal power units can provide are expressed as follows:

[0056] 1) In a high-proportion renewable energy power system, the strong uncertainty of renewable energy forecast error is the dominant factor in the system power balance risk. The total wind and solar forecast error is expressed as follows:

[0057]

[0058] in, They represent the prediction errors of wind farm and photovoltaic power station in time period t, Represents the total error of wind and solar forecast.

[0059] 2) Adopting affine strategy as a means of adjusting thermal power units to deal with wind and solar forecast errors. The actual output of thermal power units is expressed by an affine function, which takes the wind and solar forecast errors as variables. Only after the actual wind and solar output is determined can the specific value of the affine function be calculated.

[0060]

[0061] in, represents the participation factor of thermal power units; They are respectively represented as the upward / downward adjustment factors of thermal power unit i in time period t; They represent the upper and lower spinning reserve capacities of thermal power unit i in time period t respectively; It means that the thermal power units are really producing; is the power of thermal power unit i at time t; Represents the total error of wind and solar forecast.

[0062] 3) Combining the affine factor with the total error of the wind and solar prediction, we can get They can be expressed as the up-regulation and down-regulation requirements of the system respectively.

[0063] The specific description of the probabilistic power balance risk of the power grid is:

[0064] 1) When the up-ramp reserve regulation capacity of thermal power is insufficient to cover the fluctuation regulation demand under the predicted wind and solar output, the system is at risk of load shedding; when the down-ramp reserve regulation capacity of thermal power is insufficient to cover the fluctuation regulation demand under the predicted wind and solar output, the system is at risk of power abandonment, such as Figure 2 shown.

[0065] 2) Wind and solar prediction error is a random variable, then the system probabilistic power balance risk is expressed as follows:

[0066]

[0067] Where γ1 / γ2 represents the load loss / power abandonment probability allowed by the system. Formula (4) describes the distribution of wind and solar forecast error P t ψ exist Under the worst distribution, there is still a probability less than γ1 / γ2 that cannot be satisfied in formula (4), such as Figure 1 shown.

[0068] 3) According to the probability balance risk expression of formula (4), the load shedding random variable and the power abandonment random variable can be defined as follows:

[0069]

[0070] In the formula, represents the load shedding random variable, represents the curtailed power random variable.

[0071] 4) Based on the definition of risk value VaR, under a specific confidence probability, the threshold formula of the random variables of load shedding and power abandonment can be expressed as:

[0072]

[0073] In the formula, They represent the load shedding random variable threshold and the power abandonment random variable threshold in time period t respectively.

[0074] The physical meaning is to make sure that the reserve dispatch instruction of thermal power is When , the load shedding power that may occur when the system supply and demand is balanced is less than b1, and the minimum value among all b1 is the load shedding power threshold under the confidence probability β1.

[0075] The physical meaning is to make sure that the reserve dispatch instruction of thermal power is When , the power abandonment that may occur when the system supply and demand is balanced is less than b2, and the minimum value among all b2 is the power abandonment threshold under the confidence probability β2.

[0076] The risk indicators of load shedding power and power abandonment power conditions under a certain confidence probability are specifically described as:

[0077] In the probabilistic supply and demand balance optimization strategy of the power system, the goal is to seek the optimal balance point for the dispatch of thermal power reserve capacity, taking into account safety and economy, so as to minimize the large load shedding or power abandonment that may occur in actual operation, and ensure the effective execution of dispatch instructions. The conditional value at risk (CVaR) theory can quantify the large load shedding or power abandonment risks caused by the upper / lower tail risks of the probability distribution of the new energy forecast error. Based on CVaR, the risk index of the supply and demand balance of the power system with a high proportion of new energy is quantified. Under certain confidence probabilities β1 and β2, the risk index of the system's load shedding and power abandonment is as follows, which is expressed as the average value on VaR:

[0078]

[0079] In the formula, are the risk indicators of load shedding power and wind power abandonment in the system during period t, respectively; is the probability distribution function of the wind and solar forecast error.

[0080] The physical meaning is that the load shedding power exceeds its threshold The conditional expected value of this part of the load shedding power is, The physical meaning is that the power abandonment exceeds its threshold The conditional expected value of this part of the abandoned power.

[0081] In fact, when minimizing When I was there, I also got a small because Will not exceed Introducing helper functions To indicate The definition is as follows:

[0082]

[0083] In the formula, [·] + represents max{·,0}. Random variables can be used The sample approximation is:

[0084]

[0085] Further, let:

[0086]

[0087] Further, we can get:

[0088]

[0089]

[0090] Among them, b1 and b2 represent the load shedding power and power abandonment power under different probability distributions, respectively, and β1 and β2 represent the load loss and power abandonment probabilities that are not allowed by the system, respectively.

[0091] If the value is greater than 0, there is a risk of load shedding and power abandonment. If the value is equal to 0, there is no risk.

[0092] Embodiment 2 is an embodiment of the present invention, which provides a probabilistic power and electricity balance risk assessment system for a power grid, including: a regulation module, a balancing module and an assessment module;

[0093] The regulation module is used to adopt the affine strategy as the adjustment method for thermal power units to deal with the wind and solar forecast errors, define the up and down regulation requirements of the power grid and the up and down ramp reserve regulation capabilities that the thermal power units can provide;

[0094] The balance module is used to define the probabilistic power balance risk of the power grid based on probability theory;

[0095] The evaluation module is used to propose load shedding power and power abandonment power risk indicators of the power grid under a certain confidence probability based on the conditional risk value theory for evaluation.

[0096] Embodiment 3, an embodiment of the present invention, is different from the first two embodiments in that:

[0097] 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.

[0098] 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.

[0099] 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.

[0100] 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.

[0101] Example 4, reference Figure 3-Figure 6 , which is an embodiment of the present invention, provides a probabilistic power balance risk assessment method for a power grid. In order to verify the beneficial effects of the present invention, scientific demonstration is carried out through economic benefit calculation and simulation experiments.

[0102] First, for the algorithm in the above embodiment, the consumption cost is used as a variable for evaluating load balancing to measure the economic benefits of the algorithm, as shown in the following formula:

[0103] The system includes four thermal power units (G1-G4) with capacities of 455, 130, 162 and 455MW respectively; the installed capacity of wind power is 378MW, and the installed capacity of photovoltaic power is 600MW; the maximum load of the system is 1300MW.

[0104] Based on the actual and predicted historical wind and solar output values, this paper fits the historical empirical distribution of wind and solar output errors; based on the historical empirical distribution of wind and solar output errors, 1000 wind and solar output error samples are generated at each moment by random sampling.

[0105] The load shedding power and power abandonment power risk values ​​proposed in this paper are used to conduct a probabilistic power balance risk analysis on the power system with a high proportion of renewable energy. Taking the risk confidence level of 95% as an example, the system dispatch optimization results are as follows: Figure 3-6 shown.

[0106] like Figure 3 As shown in the figure, the output of new energy approaches the minimum value in the early morning. Due to the limitation of the lower limit of new energy output, the downward fluctuation range of uncertainty is limited. Therefore, the total amount of upward climbing reserve reserved at this time is the lowest in the whole day.

[0107] Figure 4 It shows that around 10 o'clock, the system's ramp-up reserve capacity is insufficient and there is a risk of load shedding. That is, at this time, relying solely on the regulation capability of thermal power units is not enough to cope with the uncertainty of new energy output. The configuration of flexible resources such as energy storage and load demand response can be guided based on this probabilistic supply and demand balance load shedding condition risk value.

[0108] Figure 5 The climbing reserve capacity is insufficient at 14 o'clock. Figure 6 From the risk value results of power abandonment conditions in each period, it can be seen that at 14 o'clock, the system has a large risk of power abandonment, which is consistent with the theoretical results.

[0109] 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 risk assessment of power grid probabilistic power balance, characterized in that: include: The affine strategy is used as a means of adjusting the thermal power units to deal with the wind and solar forecast errors, and the up and down regulation requirements of the power grid and the up and down ramp reserve regulation capabilities that the thermal power units can provide are defined; Based on probability theory, define the probabilistic power balance risk of the power grid; Based on the conditional value at risk theory, risk indicators of load shedding power and power abandonment power under a certain confidence probability are proposed for evaluation.

2. The method for risk assessment of power grid probabilistic power and quantity balance according to claim 1, characterized in that: The up and down regulation requirements are expressed as, in, They represent the prediction errors of wind farm and photovoltaic power station in time period t, represents the total error of wind and solar forecast, represents the participation factor of thermal power units; They are respectively represented as the upward / downward adjustment factors of thermal power unit i in time period t; They represent the upper and lower spinning reserve capacities of thermal power unit i in time period t respectively; It means that the thermal power units are really producing; is the power of thermal power unit i at time t; represents the total error of wind and solar forecast; They are respectively represented as the upward and downward regulation requirements of the system.

3. The method for risk assessment of power grid probabilistic power and quantity balance according to claim 2, characterized in that: The probabilistic power balance risk of the power grid is expressed as: Among them, γ1 and γ2 represent the load loss and power abandonment probabilities allowed by the system; According to the probability balance risk expression of formula (4), the load shedding random variable and the power abandonment random variable can be defined as follows: in, represents the load shedding random variable, represents the random variable of abandoned power; Based on the definition of risk value VaR, under a specific confidence probability, the threshold formula of the random variables of load shedding and power abandonment is expressed as: in, They represent the load shedding random variable threshold and the power abandonment random variable threshold in time period t respectively.

4. The method for risk assessment of power grid probabilistic power and quantity balance according to claim 3, characterized in that: The physical meaning is to make sure that the reserve dispatch instruction of thermal power is When , the load shedding power that may occur when the system supply and demand is balanced is less than b1, and the minimum value among all b1 is the load shedding power threshold under the confidence probability β1; The physical meaning is to make sure that the reserve dispatch instruction of thermal power is When , the power abandonment that may occur when the system supply and demand is balanced is less than b2, and the minimum value among all b2 is the power abandonment threshold under the confidence probability β2.

5. The method for risk assessment of power grid probabilistic electric power balance according to claim 4, characterized in that: The conditional value-at-risk theory is expressed as, in, are the risk indicators of load shedding power and wind power abandonment in the system during period t, respectively; is the probability distribution function of the wind and solar prediction error.

6. The method for risk assessment of power grid probabilistic power and quantity balance according to claim 5, characterized in that: The physical meaning is that the load shedding power exceeds its threshold The conditional expected value of this part of the load shedding power is, The physical meaning is that the power abandonment exceeds its threshold The conditional expected value of this part of the abandoned power.

7. The method for risk assessment of power grid probabilistic power and quantity balance according to claim 6, characterized in that: when minimized When, also obtained a Introducing helper functions To indicate The definition is as follows: in,[·] + represents max{·,0}; Using random variables The sample approximation is:

8. A system using the probabilistic power balance risk assessment method for a power grid as described in any one of claims 1 to 7, characterized in that: include: Regulation module, balancing module and evaluation module; The regulation module is used to adopt an affine strategy as a means of adjusting the thermal power generation unit to cope with the wind and solar power prediction error, and define the up and down regulation requirements of the power grid and the up and down ramp standby regulation capabilities that the thermal power generation unit can provide; The balancing module is used to define the probabilistic power balance risk of the power grid based on probability theory; The evaluation module is used to propose load shedding power and power abandonment power risk indicators of the power grid under a certain confidence probability based on the conditional risk value theory for evaluation.

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 method for probabilistic power balance risk assessment of a power grid as 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 method for risk assessment of probabilistic power balance of power grid according to any one of claims 1 to 7 are implemented.

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