High-proportion new energy power supply rolling planning method considering frequency safety risk constraint

Abstract

The invention discloses a high-proportion new energy power supply rolling planning method considering frequency safety risk constraints. The high-proportion new energy power supply rolling planning method considering the frequency safety risk constraint comprises the following steps: establishing an upper-layer model taking the minimum investment cost as a target and a lower-layer model taking the minimum annual operation cost and the minimum intra-day risk index value as targets; combining the established upper and lower layer targets to construct an initial power supply rolling planning double-layer model, and solving initial power supply rolling to obtain an initial thermal power generating unit start-stop state; generating a system frequency lowest point value based on a power system frequency response dynamic process in combination with the obtained initial thermal power generating unit start-stop state; presetting the total number of years of planning, inputting the frequency safety risk constraint into the lower-layer model, establishing a power supply rolling optimization double-layer model considering the frequency safety risk constraint, and solving the model to obtain a rolling planning result. The problem that the frequency safety risk is ignored in traditional power supply planning is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of rolling planning of high-proportion new energy power sources, and in particular to a rolling planning method of high-proportion new energy power sources taking into account frequency safety risk constraints. Background Art

[0002] With the proposal of the "dual carbon" goal, the integration of renewable energy represented by wind and solar into the power grid is accelerated. While a high proportion of new energy provides clean energy, it also has an adverse impact on the frequency characteristics of the system. On the one hand, in order to respond to the country's "dual carbon" goal, the future power grid will be oriented towards reducing carbon emissions, and will inevitably vigorously promote the access of renewable energy represented by wind and solar to the power grid; on the other hand, the access of a high proportion of new energy to the power grid has compressed the proportion of conventional synchronous generators, resulting in a reduction in the system's rotational inertia and primary frequency regulation capabilities, and the power grid's ability to resist fault shocks has weakened, and the system's frequency safety issues are facing severe challenges.

[0003] Traditional research has only considered frequency security in the operation phase, but has not fully considered the complexity and challenges in the power system planning phase. In practical applications, it may face problems of high cost and inefficient resource utilization. In this context, how to introduce frequency security risk constraints in planning and further guide planning with the results of operation has become an important problem that needs to be solved urgently. Summary of the invention

[0004] In order to overcome the above-mentioned defects of the prior art, an embodiment of the present invention provides a rolling planning method for a high proportion of new energy power sources taking into account frequency safety risk constraints. Through a two-layer model design with upper and lower layers linked, the problem of ignoring frequency safety risks in traditional power source planning is solved.

[0005] To achieve the above object, the present invention provides the following technical solutions: The high-proportion new energy power rolling planning method taking into account frequency safety risk constraints includes the following steps: establishing an upper model with the goal of minimizing investment cost and a lower model with the goal of minimizing annual operating cost and intraday risk index value; Combine the upper and lower layer targets to build a two-layer model for initial power supply rolling planning, solve the initial power supply rolling, and obtain the initial start-stop status of the thermal power unit; Based on the dynamic process of power system frequency response and combined with the initial start-stop status of thermal power units, the lowest point value of system frequency is generated; The total number of planning years is preset, and the frequency safety risk constraints are input into the lower-level model. A two-level model of power supply rolling optimization considering the frequency safety risk constraints is established, and the model is solved to obtain the rolling planning results.

[0006] In a preferred embodiment, the objective function with the goal of minimizing investment cost includes installed capacity constraints and total carbon emission reduction constraints.

[0007] In a preferred embodiment, the lower-level model with the goal of minimizing the annual operating cost and the intraday risk index value includes power balance constraints in time uncertainty scenarios, power constraints for new energy time series access to the grid, power constraints for load actual uncertainty scenarios, thermal power unit constraints, and energy storage constraints.

[0008] In a preferred embodiment, the thermal power unit constraints include thermal power unit output constraints, thermal power unit ramp constraints, thermal power unit minimum startup time constraints, and thermal power unit minimum shutdown time constraints.

[0009] In a preferred embodiment, the energy storage constraints include energy storage charge constraints, upper and lower limit constraints on charge, energy storage charging power constraints, energy storage discharging power constraints, energy storage charging and discharging state constraints, and energy storage charging and discharging safety constraints.

[0010] In a preferred embodiment, the system frequency minimum point value is obtained by the following method: obtaining the power generation loss based on the dynamic frequency response equation of the power system; using the obtained power generation loss as the input of the initial power supply rolling planning two-layer model, and the model outputs the system frequency deviation; and performing Laplace transformation on the dynamic frequency response equation of the power system to obtain the frequency minimum point and the time corresponding to the frequency minimum point.

[0011] One or more technical solutions provided in the embodiments of the present application have at least the following technical effects or advantages: 1. By taking into account the frequency safety risk constraints of the high proportion of new energy power rolling planning method, a two-layer model with upper and lower layer linkage is proposed, which further realizes the close integration of the upper layer investment decision and the lower layer operation optimization, and effectively solves the problem of ignoring frequency safety risks in traditional power planning. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 A flow chart of a method for rolling planning of a high proportion of new energy power sources taking into account frequency safety risk constraints provided in an embodiment of the present application; DETAILED DESCRIPTION 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.

[0013] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "include..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0014] Embodiment 1, Figure 1 The present invention provides a high-proportion new energy power rolling planning method taking into account frequency safety risk constraints, including the following steps: Establish an upper model with the goal of minimizing investment costs and a lower model with the goal of minimizing annual operating costs and intraday risk index values; Combine the upper and lower layer targets to build a two-layer model for initial power supply rolling planning, solve the initial power supply rolling, and obtain the initial start-stop status of the thermal power unit; Based on the dynamic process of power system frequency response and combined with the initial start-stop status of thermal power units, the lowest point value of system frequency is generated; The total number of planning years is preset, and the frequency safety risk constraints are input into the lower-level model. A two-level model of power supply rolling optimization considering the frequency safety risk constraints is established, and the model is solved to obtain the rolling planning results.

[0015] The upper model with the goal of minimizing investment cost has the following calculation formula for the objective function:

[0016] Where: is the objective function with the goal of minimizing investment cost, is the investment cost of new thermal power units, is the investment cost of energy storage equipment, is the discount rate, is the annual growth rate of construction cost of thermal power units, is the investment cost of the newly built i-th thermal power unit, is the annual growth rate of the construction cost of energy storage equipment, Indicates the construction status of the i-th thermal power unit to be built, is the annual growth rate of the construction cost of energy storage equipment, represents the capacity of the newly built energy storage equipment, It is a collection of thermal power units to be built.

[0017] It should be noted that the investment cost of the i-th thermal power unit is a binary variable, 1 means it has been built, and 0 means it has not been built. The number of thermal power units of each model to be built needs to be given in advance, and the capacity of the newly built energy storage equipment is a continuous variable.

[0018] The objective function with the goal of minimizing investment cost includes installed capacity constraints and total carbon emission reduction constraints, which are as follows: The installed capacity constraint is calculated as follows:

[0019] Where: L is the average load of the time series, is the installed capacity of the i-th thermal power unit, is the installed capacity of the wth wind turbine, is the installed capacity of the pth photovoltaic power generation device, is the collection of thermal power units, A collection of wind power generation devices. A collection of photovoltaic power generation devices.

[0020] The total carbon emission reduction constraint is calculated as follows:

[0021] Where: D is the number of days in the year, T is the number of time periods in each day, is the collection of thermal power units, e is the emission reduction index for that year, Forecast carbon emissions for the year, is the carbon emission of the i-th thermal power unit in the t-th time period on the d-th day.

[0022] The objective function of the lower-level model, which aims to minimize the annual operating cost and the intraday risk index value, is calculated as follows:

[0023] Where: is the weight of annual operating cost, is the start-up and shutdown cost of thermal power units, is the running cost of the time series scenario, Q is the number of scenarios, is the weight of the comprehensive risk value, It is the comprehensive risk index value.

[0024] It should be noted that the timing scenario operating costs include the timing scenario operating costs of thermal power units and the timing scenario operating costs of energy storage equipment, and the comprehensive risk index value includes intraday carbon emission risks and power balance risks.

[0025] The start-up and shutdown cost of the thermal power unit is calculated as follows:

[0026] Where: is the start-up and shutdown cost of thermal power units, is the startup cost of the i-th thermal power unit, is the shutdown cost of the ith thermal power unit, T is the number of time periods per day, is the collection of thermal power units, is the start / stop status of the i-th thermal power unit in the t-th time period, is the start / stop status of the i-th thermal power unit in the m-th time period, is the start / stop status of the i-th thermal power unit in the t-1th time period.

[0027] It should be noted that, in the start / stop status of the i-th thermal power unit in the t-th time period, 1 represents start and 0 represents shutdown.

[0028] The running cost of the time series scenario is calculated as follows:

[0029] Where: is the running cost of the time series scenario, is the annual growth rate of the operating costs of thermal power units and energy storage equipment, is the collection of thermal power units, , , is the operating cost coefficient of the i-th thermal power unit, is the output of the ith thermal power unit in the qth scenario at time t, is the operating cost of the energy storage equipment, is the charging efficiency of the energy storage device, is the charging power of the energy storage device, is the discharge efficiency of the energy storage device, is the discharge power of the energy storage device.

[0030] The comprehensive risk index value is calculated by the following formula:

[0031] Where: is the comprehensive risk index value, is the daily safe carbon emission threshold, is the expected carbon emission value for the day, It is an indicator of power balance risk caused by wind and solar power abandonment. is the power balance risk indicator caused by load shedding, is the weight of the power balance risk index caused by wind and solar power abandonment, The weight of the power balance risk index caused by load shedding.

[0032] The power balance risk index caused by wind and solar power abandonment is calculated as follows:

[0033] Where: It is an indicator of power balance risk caused by wind and solar power abandonment. is the probability of the qth time series scenario, is the predicted output of wind power at time t in the qth scenario, The output of wind power generation at time t in the qth scenario, is the predicted value of the photovoltaic power generation at time t in the qth scenario, The output of wind power generation at time t in the qth scenario.

[0034] The power balance risk index caused by load shedding is calculated as follows:

[0035] Where: is the power balance risk indicator caused by load shedding, is the probability of the qth time series scenario, is the system load at time t, is the actual load supply of the system in the qth scenario.

[0036] The lower-level model, which aims to minimize the annual operating cost and the intraday risk index value, includes power balance constraints in time uncertainty scenarios, power constraints for new energy time series access to the grid, power constraints for load actual uncertainty scenarios, constraints for thermal power units, and energy storage constraints, as follows: The power balance constraint of the time uncertainty scenario is calculated as follows:

[0037] The calculation formula for the renewable energy time-sequential grid-connected power constraint is as follows:

[0038] The calculation formula for the online power constraint in the actual load uncertainty scenario is as follows:

[0039] The thermal power unit constraint is calculated as follows:

[0040]

[0041]

[0042]

[0043] Where: is the maximum output of the i-th thermal power unit, is the minimum output of the i-th thermal power unit, is the maximum limit of the output drop of the i-th thermal power unit, is the output of the ith thermal power unit in the qth scenario at time t, is the output of the i-th thermal power unit in the q-th scenario at time t-1, is the maximum limit of the output increase of the i-th thermal power unit, is the continuous operation time of the i-th thermal power unit in the t-1 period, is the minimum continuous operation time of the i-th thermal power unit, is the continuous downtime of the i-th thermal power unit in the t-1 period, is the minimum continuous downtime of the i-th thermal power unit, is the start / stop status of the i-th thermal power unit at time t-1.

[0044] The energy storage constraints include energy storage charge constraints, upper and lower limit constraints on charge, energy storage charging power constraints, energy storage discharging power constraints, energy storage charging and discharging state constraints, and energy storage charging and discharging safety constraints, specifically: The energy storage charge constraint is calculated by the following formula:

[0045] Where: is the charge of the energy storage device at time t+1, is the charge of the energy storage device at time t, is the charging efficiency of the energy storage device, is the charging power of the energy storage device, is the discharge efficiency of the energy storage device, is the discharge power of the energy storage device.

[0046] The upper and lower limits of the charge are calculated by the following formula:

[0047] Where: is the minimum charge of the original energy storage device, is the maximum charge of the original energy storage device, represents the capacity of the newly built energy storage equipment, is the minimum state of charge of the newly built energy storage device, is the maximum state of charge of the newly built energy storage device, is the charge of the energy storage device at time t.

[0048] The energy storage charging power constraint is calculated as follows:

[0049] Where: represents the capacity of the newly built energy storage equipment, is the charging power of the energy storage device, It is the maximum charge of the original energy storage device.

[0050] The energy storage discharge power constraint is calculated as follows:

[0051] Where: represents the capacity of the newly built energy storage equipment, is the discharge power of the energy storage device, It is the maximum charge of the original energy storage device.

[0052] The energy storage charge and discharge state constraint is calculated as follows:

[0053]

[0054] Where: is the discharge power of the energy storage device, is the charging power of the energy storage device, is the charge and discharge state at time t in the qth scenario, and M is a large constant, which is 100000.

[0055] It should be noted that the charge and discharge status at time t in the qth scenario is a binary variable, 1 indicates that the energy storage is in a charging state, and 0 indicates that the energy storage is in a discharging state.

[0056] The energy storage charging and discharging safety constraint is calculated as follows:

[0057]

[0058] Where: is the charging efficiency of the energy storage device, is the charging power of the energy storage device, is the discharge efficiency of the energy storage device, is the discharge power of the energy storage device, is the maximum charge of the original energy storage device, is the charge of the energy storage device at time t, represents the capacity of the newly built energy storage equipment, It is the minimum charge of the original energy storage device.

[0059] Solve the above two-layer model of initial power rolling planning to obtain the start and stop states of the planning model, and use it as the start and stop states of the initial thermal power units.

[0060] The method for obtaining the lowest point value of the system frequency is as follows: The power generation loss is obtained based on the dynamic frequency response equation of the power system; The obtained power generation loss is used as the input of the initial power rolling planning two-layer model, and the model outputs the system frequency deviation; The dynamic frequency response equation of the power system is subjected to Laplace transformation to obtain the lowest frequency point and the time corresponding to the lowest frequency point.

[0061] The power system frequency response dynamic process includes a power system dynamic frequency response equation obtained according to the swing equation, specifically:

[0062] Where: is the frequency deviation, D is the load damping coefficient, is the power generation loss, is the increase in active power output of the thermal power unit under power generation loss, t is the current moment, is the total inertia time constant of the system.

[0063] The total inertia time constant of the system is calculated as follows:

[0064] Where: is the capacity of the i-th thermal power unit, is the inertia time constant of the i-th thermal power unit.

[0065] The system frequency deviation is calculated as follows:

[0066] Where: is the system frequency deviation, is the total inertia time constant of the system, s is the Laplace operator, D is the load damping coefficient, is the mechanical power gain factor, is the static adjustment coefficient of the thermal power unit, is the fraction of the total power produced by the high pressure turbine, is the time constant of the thermal power unit speed governor, The power generation loss.

[0067] The time constants of the thermal power unit speed regulators with different speed regulators are replaced with the same value to simplify the frequency domain expression of the system frequency deviation, which is:

[0068] Where: is the damping ratio, is the natural vibration frequency, To replace the time constant value of the thermal power unit speed regulator, is the total inertia time constant of the system, s is the Laplace operator, The power generation loss.

[0069] The damping ratio and the natural vibration frequency are calculated as follows:

[0070] By using the inverse Laplace transform and taking the derivative of the time domain expression of the system frequency deviation with respect to t, we can obtain the lowest frequency point and the time corresponding to the lowest frequency point, which is:

[0071]

[0072]

[0073] Where: To ensure the minimum limit of system frequency safety, is the lowest point of the generated frequency.

[0074] Assuming that the number of planned years is, the initial current planning year N=1, the frequency safety risk constraint is included in the lower model, and a two-layer model of power rolling optimization considering the frequency safety risk constraint is established. The model is solved to obtain the rolling planning result of this year, and the start and stop status of the thermal power unit in the last period of the Nth year is used as the initial start and stop status of the thermal power unit planned in the N+1th year. At the same time, N=N+1 is updated. If N≤Nmax, return to step 2 to update the frequency safety risk constraint, and then solve the result of the power planning for the next year; and then obtain the power optimization results of all years. The above formulas are all dimensionless and numerical calculations. The formula is a formula for the most recent real situation obtained by collecting a large amount of data and performing software simulation. The preset parameters in the formula are set by technicians in this field according to actual conditions.

[0075] The above embodiments may be implemented in whole or in part by software, hardware, firmware or any other combination. When implemented by software, the above embodiments may be implemented in whole or in part in the form of a computer program product.

[0076] Those of ordinary skill in the art will appreciate that the modules and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0077] In addition, each functional module in each embodiment of the present application may be integrated into one processing module, or each module may exist physically separately, or two or more modules may be integrated into one module.

[0078] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

[0079] Finally: The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A high-proportion new energy power rolling planning method taking into account frequency safety risk constraints, characterized in that: The following steps are involved: Establish an upper model with the goal of minimizing investment costs and a lower model with the goal of minimizing annual operating costs and intraday risk index values; Combine the upper and lower layer targets to build a two-layer model for initial power supply rolling planning, solve the initial power supply rolling, and obtain the initial start-stop status of the thermal power unit; Based on the dynamic process of power system frequency response and combined with the initial start-stop status of thermal power units, the lowest point value of system frequency is generated; The total number of planning years is preset, and the frequency safety risk constraints are input into the lower-level model. A two-level model of power supply rolling optimization considering the frequency safety risk constraints is established, and the model is solved to obtain the rolling planning results.

2. The high-proportion new energy power rolling planning method taking into account frequency safety risk constraints as claimed in claim 1 is characterized in that: The upper model with the goal of minimizing investment cost has the following calculation formula for the objective function: Where: is the objective function with the goal of minimizing investment cost, is the investment cost of new thermal power units, is the investment cost of energy storage equipment, is the discount rate, is the annual growth rate of construction cost of thermal power units, is the investment cost of the newly built i-th thermal power unit, The annual growth rate of construction cost of energy storage equipment, Indicates the construction status of the i-th thermal power unit to be built, The annual growth rate of construction cost of energy storage equipment, represents the capacity of the newly built energy storage equipment, It is a collection of thermal power units to be built.

3. The high-proportion new energy power rolling planning method taking into account frequency safety risk constraints as claimed in claim 2 is characterized in that: The objective function with the goal of minimizing investment cost includes installed capacity constraints and total carbon emission reduction constraints, which are as follows: The installed capacity constraint is calculated as follows: Where: L is the average load of the time series, is the installed capacity of the i-th thermal power unit, is the installed capacity of the wth wind turbine, is the installed capacity of the pth photovoltaic power generation device, is the collection of thermal power units, A collection of wind power generation devices. A collection of photovoltaic power generation devices; The total carbon emission reduction constraint is calculated as follows: Where: D is the number of days in a year, T is the number of time periods in each day, is the collection of thermal power units, e is the annual emission reduction index, For the annual forecast of carbon emissions, is the carbon emission of the i-th thermal power unit in the t-th time period on the d-th day.

4. The high-proportion new energy power rolling planning method taking into account frequency safety risk constraints as claimed in claim 3 is characterized in that: The objective function of the lower-level model, which aims to minimize the annual operating cost and the intraday risk index value, is calculated as follows: Where: is the weight of annual operating cost, is the start-up and shutdown cost of thermal power units, is the running cost of the time series scenario, Q is the number of scenarios, is the weight of the comprehensive risk value, It is the comprehensive risk index value.

5. The high-proportion new energy power rolling planning method taking into account frequency safety risk constraints as claimed in claim 4 is characterized in that: The start-up and shutdown cost of the thermal power unit is calculated as follows: Where: is the start-up and shutdown cost of the thermal power unit, is the startup cost of the i-th thermal power unit, T is the number of time periods per day, is the collection of thermal power units, is the start / stop status of the i-th thermal power unit in the t-th time period, is the start / stop status of the i-th thermal power unit in the m-th time period, is the start / stop status of the i-th thermal power unit in the t-1th time period.

6. The high-proportion new energy power rolling planning method taking into account frequency safety risk constraints as claimed in claim 4 is characterized in that: The running cost of the time series scenario is calculated as follows: Where: is the running cost of the time series scenario, is the annual growth rate of the operating costs of thermal power units and energy storage equipment, is the collection of thermal power units, , , is the operating cost coefficient of the i-th thermal power unit, is the output of the ith thermal power unit in the qth scenario at time t, is the operating cost of the energy storage equipment, is the charging efficiency of the energy storage device, is the charging power of the energy storage device, is the discharge efficiency of the energy storage device, is the discharge power of the energy storage device.

7. The high-proportion new energy power rolling planning method taking into account frequency safety risk constraints as claimed in claim 6 is characterized in that: The lower-level model, which aims to minimize the annual operating cost and the intraday risk index value, includes power balance constraints in time uncertainty scenarios, power constraints for new energy time series access to the grid, power constraints for load actual uncertainty scenarios, constraints for thermal power units, and energy storage constraints; The thermal power unit constraints include thermal power unit output constraints, thermal power unit ramp constraints, thermal power unit minimum startup time constraints, and thermal power unit minimum shutdown time constraints, specifically: Where: is the maximum output of the i-th thermal power unit, is the minimum output of the i-th thermal power unit, is the maximum limit of the output drop of the i-th thermal power unit, is the output of the ith thermal power unit in the qth scenario at time t, is the output of the i-th thermal power unit in the q-th scenario at time t-1, is the maximum limit of the output increase of the i-th thermal power unit, is the continuous operation time of the i-th thermal power unit in the t-1 period, is the minimum continuous operation time of the i-th thermal power unit, is the continuous downtime of the i-th thermal power unit in the t-1 period, is the minimum continuous downtime of the i-th thermal power unit, is the start / stop status of the i-th thermal power unit at time t-1.

8. The high-proportion new energy power rolling planning method taking into account frequency safety risk constraints as claimed in claim 7 is characterized in that: The energy storage constraints include energy storage charge constraints, upper and lower limit constraints on charge, energy storage charging power constraints, energy storage discharging power constraints, energy storage charging and discharging state constraints, and energy storage charging and discharging safety constraints, specifically: The energy storage charge constraint is calculated by the following formula: Where: is the charge of the energy storage device at time t+1, is the charge of the energy storage device at time t, is the charging efficiency of the energy storage device, is the charging power of the energy storage device, is the discharge efficiency of the energy storage device, is the discharge power of the energy storage device; The upper and lower limits of the charge are calculated by the following formula: Where: is the minimum charge of the original energy storage device, is the maximum charge of the original energy storage device, represents the capacity of the newly built energy storage equipment, is the minimum state of charge of the newly built energy storage device, is the maximum state of charge of the newly built energy storage device, is the charge of the energy storage device at time t; The energy storage charging power constraint is calculated as follows: Where: represents the capacity of the newly built energy storage equipment, is the charging power of the energy storage device, The maximum charge of the original energy storage equipment; The energy storage discharge power constraint is calculated as follows: Where: represents the capacity of the newly built energy storage equipment, is the discharge power of the energy storage device, The maximum charge of the original energy storage equipment; The energy storage charge and discharge state constraint is calculated as follows: Where: is the discharge power of the energy storage device, is the charging power of the energy storage device, is the charge and discharge state at time t in the qth scenario, and M is a large constant, which is 100000.

9. The high-proportion new energy power rolling planning method taking into account frequency safety risk constraints as claimed in claim 8, characterized in that: The method for obtaining the lowest point value of the system frequency is as follows: The power generation loss is obtained based on the dynamic frequency response equation of the power system; The obtained power generation loss is used as the input of the initial power rolling planning two-layer model, and the model outputs the system frequency deviation; The dynamic frequency response equation of the power system is subjected to Laplace transformation to obtain the lowest frequency point and the time corresponding to the lowest frequency point.

10. The high-proportion new energy power rolling planning method taking into account frequency safety risk constraints as claimed in claim 9, characterized in that: The system frequency minimum point value is calculated by the following formula: Where: is the lowest frequency point generated, is the damping ratio, is the natural vibration frequency, is the total inertia time constant of the system, is the power generation loss, is the value of the time constant of the speed regulator of the thermal power unit, and D is the load damping coefficient.

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