Novel power system climbing demand multi-dimensional evaluation method considering source load fluctuation coupling characteristics

Abstract

The invention relates to the technical field of power system flexibility demand evaluation, in particular to a novel power system climbing demand multi-dimensional evaluation method considering source load fluctuation coupling characteristics. Comprising the steps that a source load fluctuation coupling characteristic integrated analysis framework including new energy climbing coverage rate calculation, climbing relieving time period / aggravating time period recognition and climbing demand relieving / aggravating rate quantitative calculation is constructed; constructing a novel electric power system climbing demand multi-dimensional evaluation index system including a short-time climbing rate demand, continuous climbing time, continuous climbing capacity and a continuous climbing rate; according to the method, multi-level collaborative linkage is realized, the time sequence distribution characteristics and the dynamic evolution law of the system climbing demand under the source-load fluctuation coupling effect are comprehensively described, and the influence intensity and the action path of the source-load fluctuation coupling characteristic on the whole system climbing demand are accurately quantified; and the full life cycle characteristics of the climbing demand from the instantaneous triggering to the continuous process and from the scale volume to the adjustment intensity are comprehensively depicted.

Description

Technical Field

[0001] This invention relates to the field of power system flexibility demand assessment technology, and in particular to a novel multidimensional assessment method for power system ramping demand that considers the coupling characteristics of source-load fluctuations. Background Technology

[0002] The power system ramp-up problem becomes prominent after renewable energy is integrated into the grid: In traditional power systems, the system ramp-up demand stems from the temporal fluctuations of the load and is driven by the load alone. Load fluctuations generally exhibit certain regularity, with relatively low uncertainty, and their rate of change is slow, with daily fluctuations below 50%. The source side is mainly controlled and adjustable thermal power, with a regulation rate of 1.5%~3% / min of rated capacity and an adjustable range of 50%~100% of rated capacity, which can fully cover load fluctuations. Therefore, the ramp-up problem is not significant in traditional power systems. However, in new power systems, the ramp-up demand stems from the coupling relationship between load fluctuations and renewable energy fluctuations, driven by both the source and load sides. The renewable energy output on the source side exhibits strong volatility and randomness, which, after coupling with load fluctuations on the load side, leads to an increase in the overall system fluctuation intensity, with fluctuation amplitudes exceeding 50%, and prolonged unidirectional fluctuations, increasing the system's regulation pressure. On the other hand, the integration of new energy sources has compressed the output space of traditional generating units, reducing the adjustable capacity of ramping resources in the system. This results in the existing flexibility resources being unable to meet the fluctuation changes after source-load fluctuation coupling, making the ramping problem in new power systems increasingly serious.

[0003] Limitations of existing methods: The mechanism by which source-load fluctuation coupling affects ramp demand remains unclear. In high-proportion renewable energy power systems, the volatility of both the source and load sides is significantly enhanced, and they form a complex interactive coupling relationship. However, existing methods still have limitations in analyzing the intrinsic correlation mechanism between this and ramp demand. Some methods focus on modeling single-side source-load fluctuations, characterizing the single-side fluctuation features through probability distributions and time series predictions, but neglecting the superposition and offsetting effects of double-side fluctuations, making it difficult to reflect the true fluctuation trend of net load. A few studies that focus on source-load correlation are mostly limited to statistical analysis, failing to delve into the dynamic coupling laws of fluctuation direction (same direction / opposite direction), fluctuation degree (strong / weak), and fluctuation time series. In fact, the system ramp demand is essentially determined by the rapid changes in net load, and the magnitude, rate, and duration of net load changes depend precisely on the time series coupling relationship between the source and load sides. Same-side fluctuations may reduce ramp demand, while opposite-side fluctuations will increase ramp demand. Time series differences further affect the distribution and peak value of ramp demand.

[0004] The assessment of ramp-up demand relies on a single indicator: In new power systems with a high proportion of renewable energy connected to the grid, ramp-up demand exhibits dynamic and continuous characteristics, and existing assessment methods suffer from the significant drawback of relying on a single indicator. Mainstream methods often focus on a single dimension of assessment at fixed time intervals, such as calculating instantaneous ramp-up rates or capacity demand, failing to construct a multi-dimensional system covering the time dimension. The core flaw is that it ignores the temporal continuity and correlation between renewable energy output and load fluctuations. That is, ramp-up demand in adjacent time periods exhibits dynamic correlation and cumulative effects; the cumulative effect of continuous ramp-up can lead to long-term ramp-up problems. Existing methods cannot capture this overlapping ramp-up pressure across different time periods, resulting in final assessment results that fail to comprehensively depict the true intensity and sustainability of ramp-up demand.

[0005] There is an urgent need for a method that can quantitatively analyze the impact of source-load fluctuation coupling characteristics on system ramping demand and provide a multi-dimensional assessment of ramping demand. This method should comprehensively characterize the dynamic evolution of ramping demand under source-load coupling, be adaptable to different renewable energy penetration rates, wind-solar ratios, and other scenarios and time scales, and achieve a full-dimensional analysis of system ramping demand, providing reliable support for the optimization of flexible resource allocation and scheduling strategies in new power systems. Summary of the Invention

[0006] This invention provides a novel multi-dimensional assessment method for power system ramping demand that considers the coupling characteristics of source-load fluctuations. It establishes an integrated analysis framework for the impact of source-load fluctuation coupling characteristics on ramping demand, enabling multi-level collaborative linkage to comprehensively characterize the temporal distribution characteristics and dynamic evolution of system ramping demand under the action of source-load fluctuation coupling. It accurately quantifies the impact intensity and action path of source-load fluctuation coupling characteristics on the overall system ramping demand, and constructs a multi-dimensional indicator system and closed-loop assessment model to achieve a comprehensive characterization of the entire life cycle characteristics of ramping demand, from the moment of triggering to the continuous process, and from the scale to the intensity of adjustment.

[0007] To achieve the above objectives, the present invention employs the following technical solution: A novel multidimensional assessment method for power system ramping demand considering the coupling characteristics of source-load fluctuations includes the following: S1. Construct an integrated analysis framework for the coupling characteristics of source-load fluctuations, including calculation of new energy ramp-up coverage, identification of ramp-up relief / aggravation periods, and quantitative calculation of ramp-up demand relief / aggravation rate. Define the coupling relationship between new energy and load fluctuations, accurately identify ramp-up demand relief / aggravation periods, and quantitatively calculate the relationship between ramp-up demand relief rate and aggravation rate. S2. Construct a multi-dimensional evaluation index system for the ramping demand of a new type of power system, including short-term ramping rate demand, continuous ramping time, continuous ramping capacity, and continuous ramping rate, and form a closed-loop evaluation model that deeply integrates the instantaneous response-long-term maintenance time dimension and the capacity scale-rate intensity characteristic dimension suitable for the new type of power system.

[0008] Furthermore, the formula for calculating the coverage rate of the new energy ramp is as follows: ; in, Let t be the magnitude of the new energy ramp-up coverage rate, which characterizes the fluctuation coupling relationship between new energy fluctuations and load fluctuations; and These represent the load ramp-up and the new energy ramp-up at time t, respectively. when When the value is greater than 1, it indicates that the fluctuation of new energy sources and the fluctuation of loads fluctuate in the same direction, and the fluctuation of new energy sources completely covers the fluctuation of loads with a surplus. when When =1, it means that the fluctuation of new energy sources and the fluctuation of loads fluctuate in the same direction, and the fluctuation of new energy sources completely covers the fluctuation of loads. When 0 < When <1, it indicates that the fluctuation of new energy sources and the fluctuation of load fluctuate in the same direction, and the fluctuation of new energy sources can only cover part of the fluctuation of load. When -1 < When the value is less than 0, it indicates that the fluctuation of new energy sources is opposite to the fluctuation of load, and the intensity of the fluctuation of new energy sources is lower than that of the fluctuation of load. when When ≤-1, it indicates that the fluctuation of new energy sources fluctuates in the opposite direction to the fluctuation of load, and the intensity of the fluctuation of new energy sources exceeds that of the fluctuation of load.

[0009] Furthermore, the identification of the slope relief / intensification period specifically includes: (1) Period of reduced demand for hill climbing: Period of easing demand for hill climbing Use new energy ramp coverage Characterization: ; When the coverage rate of new energy ramp-up during a certain period Satisfy 0 < When the value is less than 1, the actual ramp-up demand of the system after the coupling of new energy fluctuations and load fluctuations is less than the traditional load ramp-up demand. When =1, the actual ramping requirement of the system is 0; 1 < The actual ramping demand caused by excess fluctuations at time <2 is still less than the traditional load ramping demand; (2) Periods of heightened demand for hill climbing: Period of heightened demand for hill climbing use Characterization: ; When the coverage rate of new energy ramp-up <0, the actual ramping demand after the coupling of new energy fluctuations and load fluctuations must be greater than the traditional load ramping demand; when ≥2, actual climbing requirements are greater; (3) Identification of climbing periods: By obtaining the temporal distribution of climbing relief / intensification periods, climbing relief / intensification periods can be distinguished. ; in, For the i-th climbing period, As an indicator function, when t i ∈T r When t is taken as 1, i ∈T a Take -1.

[0010] Furthermore, the ramp-up demand mitigation rate / aggravation rate, wherein: Climbing demand relief rate This refers to the ratio of the total reduction in ramp-up demand during periods of reduced ramp-up demand due to renewable energy output to the total ramp-up demand of traditional loads when there is no renewable energy. ; Increased demand for hill climbing This refers to the ratio of the total increase in ramp-up demand during periods of heightened demand due to renewable energy output to the total ramp-up demand of traditional loads when there is no renewable energy: .

[0011] Furthermore, the short-term ramp rate requirement is measured by the coverage rate of new energy ramps. Characterization: ; in, Let be the system's ramp capacity requirement at time t; To meet the climbing speed requirements, when When the value is greater than 0, it represents the required uphill speed, denoted as . ,when When <0, it represents the downhill climbing rate requirement, denoted as .

[0012] Furthermore, the continuous ramp time is the total duration of a single unidirectional ramp demand from start to finish during power system operation, characterizing the system's requirements for the long-term maintenance capability of various regulating resources, as shown in the following formula: ; in, and These represent the duration of the nth continuous uphill / downhill phase of the system, respectively. and These are the end time and start time of the nth continuous uphill period of the system, respectively; and These are the end time and start time of the nth continuous downhill climbing period of the system, respectively.

[0013] Furthermore, the total capacity required by the continuous climbing capacity characterization system during a single unidirectional climbing period is given by the following formula: ; in, This represents the continuous uphill capacity requirement during the nth uphill period. This represents the continuous downhill capacity requirement during the nth downhill period. The total unidirectional ramp capacity requirement during the day is represented as the sum of the system's unidirectional ramp capacity requirements to meet the power balance during the day, as shown in the following formula: ; in, This represents the total capacity demand for the day's upward climb. This represents the total capacity demand during the day's downhill climb. Calculate the intraday ramp capacity gap: ; Wherein, ΔC represents the intraday ramp capacity gap; If the intraday ramp capacity gap is greater than 0, it means that the total ramp capacity demand is greater than the total ramp capacity demand, and energy input type regulation resources need to be configured. If the intraday ramp capacity gap is equal to 0, then the total ramp capacity demand and the total ramp capacity demand are equal, and energy transfer type adjustment resources need to be configured. If the intraday ramp capacity gap is less than 0, it means that the total ramp capacity demand is less than the total ramp capacity demand, and energy absorption type regulation resources need to be configured.

[0014] Furthermore, the continuous ramp rate is the average rate of change of the system's required adjustment power per unit time during a complete continuous ramp event, as shown in the following formula: ; in, This represents the required rate of increase for the nth continuous uphill period. This represents the required rate of descent during the nth continuous descent period.

[0015] Compared with the prior art, the beneficial effects of the present invention are: 1) This invention, relying on a multi-stage collaborative analysis framework, defines the correlation between the direction and intensity of source-load fluctuations through the coverage rate of new energy ramping, accurately divides the periods of mitigation / aggravation of ramping demand, and quantifies the magnitude of mitigation and aggravation effects. This successfully overcomes the limitations of existing technologies that fail to adequately analyze the intrinsic relationship between source-load fluctuation coupling and ramping demand. This framework not only accurately identifies the core driving factors of ramping demand under different fluctuation scenarios but also clearly presents the distribution characteristics and dynamic change path of ramping demand over time. It provides a clear analytical logic for a deeper understanding of the dual impact of system ramping demand after new energy access, filling a gap in the research on the evolution of ramping demand under source-load coupling. 2) To address the shortcomings of traditional assessment methods, such as the single indicator and neglect of time continuity and cumulative effects, this invention constructs a multi-dimensional indicator matrix that includes short-term ramp rate, continuous ramp duration, continuous ramp capacity, and continuous ramp rate. This matrix achieves a deep integration of the time dimension of "instantaneous response - long-term maintenance" and the characteristic dimension of "capacity scale - adjustment intensity". It can fully capture the characteristics of ramp demand from the moment of triggering to the continuous process, and from the scale to the adjustment intensity throughout the entire life cycle. It effectively solves the problems of traditional methods failing to reflect the cumulative effect of long-term ramps and the one-sided assessment results, and significantly improves the accuracy of characterizing the true intensity and continuous attributes of ramp demand in new power systems. 3) This invention possesses excellent adaptability to diverse scenarios, covering application needs across different levels of new energy penetration, wind and solar resource ratios, and various time scales, and is highly compatible with the complex operational dynamics of new power systems. Its evaluation results provide comprehensive and reliable evidence for the optimized allocation of flexibility resources in new power systems, the rational arrangement of unit combinations, the scientific selection of regulation resource types, and the formulation of dispatching schemes. This effectively alleviates the ramp-up and regulation pressure faced by the system after a high proportion of new energy sources are connected to the grid, providing technical support for ensuring the safe and stable operation of new power systems. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the load and new energy output curves in an embodiment of the present invention.

[0017] Figure 2 This is a distribution map of the coverage rate of new energy ramps in an embodiment of the present invention.

[0018] Figure 3 This is a time-series distribution diagram of the hill-climbing relief / intensification periods in an embodiment of the present invention.

[0019] Figure 4 This is a schematic diagram illustrating the impact rate of hill climbing demand in an embodiment of the present invention.

[0020] Figure 5 This is a short-term climbing rate distribution diagram in an embodiment of the present invention.

[0021] Figure 6 This is a distribution map of continuous hill-climbing demand in an embodiment of the present invention.

[0022] Figure 7 This is a distribution map of the total daily climbing demand in an embodiment of the present invention.

[0023] Figure 8 This is a distribution diagram of the climbing demand gap in an embodiment of the present invention. Detailed Implementation

[0024] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings: This invention presents a novel multi-dimensional assessment method for power system ramping demand that considers the coupling characteristics of source-load fluctuations, comprehensively characterizing the ramping demand features of new power systems. It establishes an integrated analysis framework covering "calculation of new energy ramping coverage, accurate identification of ramping relief / intensification periods, and quantitative calculation of system ramping demand relief / intensification rate". Through multi-level collaborative linkage, it comprehensively characterizes the temporal distribution characteristics and dynamic evolution law of system ramping demand under the action of source-load fluctuation coupling, and accurately quantifies the influence intensity and action path of source-load fluctuation coupling characteristics on the overall system ramping demand. A multi-dimensional evaluation index system is constructed, including short-term ramp rate, continuous ramp time, continuous ramp capacity, and continuous ramp rate. This system, with "full coverage of the time dimension and full penetration of the characteristic dimension" as its core, forms a closed-loop evaluation model suitable for new power systems, deeply integrating the "instantaneous response-long-term maintenance" time dimension and the "capacity scale-rate intensity" characteristic dimension. This enables a comprehensive characterization of the entire lifecycle of ramp demand, from the moment of triggering to the continuous process, and from scale to adjustment intensity.

[0025] S1. Construct an integrated analysis framework for the coupling characteristics of source-load fluctuations; S1.1, New energy ramp coverage rate; At any given moment, if the fluctuations in renewable energy and load satisfy the condition that their directions and magnitudes are exactly equal, then the renewable energy ramp-up is considered to completely cover the load ramp-up, and the overall system ramp-up demand is zero. If the above condition is not met, the overall system will still generate ramp-up demand. Therefore, the renewable energy ramp-up coverage rate C can be defined. t To characterize the wave-like coupling relationship between the two: (1) in, Let t be the magnitude of the new energy ramp-up coverage rate, which characterizes the fluctuation coupling relationship between new energy fluctuations and load fluctuations; and These represent the load ramp-up and the new energy ramp-up at time t, respectively. New energy ramp coverage rate C tThe positive or negative sign indicates the correlation between the two fluctuation directions, and the new energy ramp-up coverage rate C t The magnitude of the value can represent the correlation between the fluctuation intensity of the two factors and also identify the dominant factors in the system's ramp-up demand, as shown in Table 1: Table 1. Statistics of the Main Factors Contributing to the Ramp-up Coverage Rate (Ct) of New Energy Sources and System Ramp-up Demand S1.2 Identification of periods of reduced / intensified demand for hill climbing; (1) Period of easing demand for hill climbing; When the actual ramp-up demand of the system during a given period is less than the ramp-up demand of the traditional load when there is no new energy source, this period is defined as the period of increased ramp-up demand, denoted as _____. ; When the coverage rate of new energy ramp-up during a certain period Satisfy 0 < When 1 < 1, it indicates that the direction of new energy and load fluctuation is consistent and only partially covers the load fluctuation. The actual ramp-up demand of the system after the coupling of the two is less than the traditional load ramp-up demand; when 1 ≤ When <2, the direction of source load fluctuation remains the same: When the value is 1, the fluctuation of new energy sources exactly covers the fluctuation of load, and the actual ramp-up demand of the system is 0; when 1 < Even after the load fluctuations are covered by renewable energy fluctuations (less than 2 hours), there is still a surplus. The actual ramp-up demand resulting from the surplus fluctuations is still less than the ramp-up demand from traditional loads. In summary, the period of reduced ramp-up demand... Available new energy hill-climbing coverage Characterization: (2) (2) Periods when the demand for climbing slopes intensifies; After the integration of renewable energy sources, the actual ramp-up demand of the system during this period is greater than the ramp-up demand of the traditional load when there is no renewable energy source. This period is characterized by intensified ramp-up demand and is denoted as [missing information]. When the coverage rate of new energy ramp-up <0, the source load fluctuations are in opposite directions, and the actual ramp-up demand after coupling will definitely be greater than the traditional load ramp-up demand; when ≥2, source and load fluctuations are in the same direction, and the fluctuation of new energy surplus exceeds that of traditional load fluctuations, resulting in greater actual ramp-up demand; in summary, the period of easing ramp-up demand... Available Characterization: (3) (3) Identification of climbing periods; To effectively distinguish between the periods of hill-climb relief and exacerbation and to obtain their temporal distribution, the following distinctions are made: (4) in, For the i-th climbing period, As an indicator function, when t i ∈T r When t is taken as 1, i ∈T a Take -1.

[0026] S1.3, Rate of relief / intensification of ramp-up demand; The rate of relief and the rate of aggravation of ramp-up demand are core indicators for quantifying the impact of new energy sources on the system's ramp-up adjustment pressure; relief rate Under the influence of new energy power output, The ratio of the total reduced ramp demand during a given period to the total ramp demand of traditional loads when there is no new energy source is used to accurately measure the relative reduction in the system's ramp adjustment pressure and to intuitively present the positive contribution efficiency of new energy sources in alleviating ramp demand. aggravation rate This refers to the output of new energy sources. The ratio of the total increase in ramp-up demand during a given period to the total ramp-up demand of traditional loads when there is no new energy source is primarily used to measure the relative increase in the system's ramp-up adjustment pressure, clearly revealing the magnitude and potential risks of the reverse impact of new energy sources on ramp-up demand. (5) (6).

[0027] S2. Construct a new multi-dimensional evaluation index system for power system ramp-up demand; S2.1, Short-term climbing rate requirement; Short-time ramp rate demand is a core indicator characterizing the magnitude of power changes within short time intervals (5 / 10 / 15 min), measured in MW / min. In new power systems, it not only depicts the magnitude of short-time system fluctuations after source-load coupling but also reflects the instantaneous response strength that various regulatory resources must meet to maintain active power balance. It is a key indicator for adapting to load fluctuations and renewable energy output fluctuations. A higher short-time ramp rate demand indicates a higher regulation risk for the system. The short-time ramp rate demand can be represented by the renewable energy ramp rate coverage rate. Characterization: (7) in, Let be the system's ramp capacity requirement at time t; To meet the climbing speed requirements, when When the value is greater than 0, it represents the required uphill speed, denoted as . ,when When <0, it represents the downhill climbing rate requirement, denoted as .

[0028] S2.2, Continuous climbing time; In new power systems, the uncontrollable output of new energy sources leads to a time mismatch between their output and load absorption capacity, resulting in long-term unidirectional power demand. Continuous ramp-up time refers to the total duration of a single unidirectional ramp-up demand from start to finish during power system operation. It characterizes the system's long-term maintenance requirements for various regulatory resources and is an important indicator for assessing the system's long-term regulatory capacity requirements. (8) in, and These represent the duration of the nth continuous uphill / downhill phase of the system, respectively. and These are the end time and start time of the nth continuous uphill period of the system, respectively; and These are the end time and start time of the nth continuous downhill climbing period of the system, respectively.

[0029] S2.3, Continuous climbing capacity; Unlike the single-point ramp capacity in short-term ramp rate, continuous ramp capacity focuses more on the cumulative effect of continuous fluctuations in the system after source load fluctuation coupling. It represents the total capacity required by the system in a single unidirectional ramp period and is a key indicator for quantifying the scale of long-term ramp capacity demand. (9) in, This represents the continuous uphill capacity requirement during the nth uphill period. This represents the continuous downhill capacity requirement during the nth downhill period. The total intraday unidirectional ramp capacity demand is represented as the sum of the system's unidirectional ramp capacity demands to meet intraday power balance. Its assessment results can provide a reference for day-ahead regulation resource allocation and unit combination. (10) in, This represents the total capacity demand for the day's upward climb. This represents the total capacity demand during the day's downhill climb. The intraday ramp capacity gap represents the difference between the total intraday ramp capacity demand and the total ramp capacity demand. Its assessment results can provide a reference for the selection of day-ahead regulation resource types. If the value is greater than 0, it means that the total ramp capacity demand is greater than the total ramp capacity demand, and energy input type regulation resources need to be configured; if the value is equal to 0, it means that the two are equal, and energy transfer type regulation resources need to be configured; if the value is less than 0, it means that the total ramp capacity demand is less than the total ramp capacity demand, and energy absorption type regulation resources need to be configured. (11) Wherein, ΔC represents the intraday ramp capacity gap.

[0030] S2.4, Continuous climbing rate; The sustained ramp rate is a key indicator proposed to address the long-term, unidirectional power regulation requirements of new power systems. It is defined as the average rate of change of the power regulation required by the system per unit time during a complete sustained ramp event. Its value is equal to the ratio of the total sustained ramp capacity to the sustained ramp time. This indicator quantifies the average regulation intensity that flexibility resources must maintain stably to meet the power balance of the system. Unlike the short-term ramp rate, which focuses on instantaneous fluctuations, it emphasizes the durability of regulation capability and is the core basis for evaluating the system's ability to cope with long-term ramp demands. (12) in, This represents the required rate of increase for the nth continuous uphill period. This represents the required rate of descent during the nth continuous descent period.

[0031] In this invention, an integrated analysis framework for source-load coupling is constructed, which overcomes the limitations of existing technologies in analyzing the inherent relationship between source-load fluctuation coupling and ramp demand. By defining the direction and intensity relationship of source-load fluctuations, accurately dividing the periods of ramp demand mitigation / aggravation, and quantifying the impact of new energy on ramp demand, a multi-linked analysis logic is formed, clearly presenting the temporal distribution characteristics and dynamic evolution law of ramp demand under the action of source-load coupling.

[0032] An innovative multi-dimensional closed-loop evaluation index system is developed. Addressing the shortcomings of traditional evaluation indicators, such as their singularity and neglect of time continuity and cumulative effects, an index matrix is ​​constructed that covers "short-term ramp rate, continuous ramp time, continuous ramp capacity, and continuous ramp rate". This achieves a deep integration of the time dimension of "instantaneous response - long-term maintenance" and the characteristic dimension of "capacity scale - adjustment intensity", thus fully depicting the characteristics of the entire life cycle of ramp demand.

[0033] It has the ability to adapt to multiple scenarios and can flexibly cover application scenarios with different new energy penetration rates, wind and solar resource ratios and multiple time scales. It is highly compatible with the complex operation of new power systems, and its evaluation results can provide comprehensive and reliable technical support for the optimization of flexible resource allocation, unit combination arrangement, selection of regulation resource types and formulation of dispatching schemes.

[0034] The following embodiments are implemented based on the technical solution of the present invention, providing detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following embodiments. Unless otherwise specified, the methods used in the following embodiments are conventional methods.

[0035] Example Actual operating data from a certain month in a northeastern province was selected, with a data sampling interval of 15 minutes. The method described in this invention was used for analysis. The load and renewable energy output on a certain day are shown as dashed lines. Figure 1 As shown in the attached figures, the following explanation will be provided in conjunction with the accompanying drawings.

[0036] 1. Analysis of daily load fluctuation characteristics; Now select Figure 1 The corresponding load and new energy output are analyzed, and the new energy ramp-up coverage rate C is calculated using equation (1). t Distribution as Figure 2 As shown, the temporal distribution of the slope relief / intensification periods is calculated using equations (2) to (4). Figure 3 As shown, the hill-climb demand relief rate calculated using Equation (5) is 58.11%, and the hill-climb demand aggravation rate calculated using Equation (6) is 148.72%.

[0037] according to Figure 2 It can be seen that load is the dominant factor (-1 < <1) The climbing rate accounts for 45%, dominated by new energy sources (1< or The climbing requirement of <-1) accounts for 55%; the coverage rate of new energy climbing is... The maximum value occurred during period 51-52 at 21.37, and the minimum value occurred during period 52-53 at -63.71, indicating that at this time, the ramp-up of new energy far exceeded the ramp-up of the load, becoming the dominant factor in the system's ramp-up demand; Figure 3 It can be seen that the period of reduced ramp-up demand accounts for 31% of the total day, and its distribution is relatively scattered. The largest concentration area is the period from 81 to 95, indicating that the output of new energy is relatively small during this period. The period of increased ramp-up demand accounts for 69% of the total day, and its distribution is relatively concentrated.

[0038] Calculate the daily hill-climbing demand relief rate and aggravation rate for the month using equations (5) to (6), such as Figure 4 As shown.

[0039] Depend on Figure 4 It can be seen that the easing rate of demand for hill climbing in that month... The distribution ranges from 18.87% to 61.27%, with an aggravation rate. The percentages ranged from 82.82% to 246.23%; the significant difference between the two within the day indicates that the grid connection of new energy sources has significantly increased the system's ramp-up requirements.

[0040] 2. Multidimensional assessment of climbing requirements; The system ramp-up requirements are quantified using the multi-dimensional evaluation index system constructed by this invention. Each index is calculated using equations (7) to (9) and (12), as follows: Figure 5 The figure shows the short-term climb rate distribution. A continuous climb time-continuous climb rate-continuous climb capacity distribution diagram is plotted with time on the horizontal axis and continuous climb rate on the vertical axis. Figure 6 As shown.

[0041] Depend on Figure 5 It can be seen that when the time interval is 15 minutes, the uphill events account for 56%, and their uphill rates are distributed in the range of 0.14 to 36.09 WM / min; the downhill events account for 44%, and their uphill rates are distributed in the range of 0.09 to 31.12 WM / min.

[0042] Depend on Figure 6 It can be seen that, in the uphill climbing events, typical uphill events are distributed in two regions: 1) the maximum sustained uphill rate is 18.17 MW / min, the time is 60 min (63-66), and the sustained uphill capacity is 1090.18 MW; 2) the maximum sustained uphill capacity is 3265.98 MW, the time is 225 min (15-29), and the sustained uphill rate is 14.52 MW / min; In the downhill climbing events, typical climbing events are distributed in one area, with a maximum sustained climbing rate of 18.04 WM / min, a duration of 90 min (69–74), and a sustained climbing capacity of 1623.17 WM.

[0043] Calculate the daily total uphill / downhill demand and daily total uphill demand deficit for the month using formulas (10) to (11), such as Figure 7 , 8 As shown.

[0044] Depend on Figure 7 , 8 It is known that the maximum input-type regulation resource required this month is 6217.79MW; the maximum absorption-type regulation resource required is 7244.85MW.

Claims

1. A novel multi-dimensional assessment method for power system ramping demand considering the coupling characteristics of source-load fluctuations, characterized in that, Includes the following: S1. Construct an integrated analysis framework for the coupling characteristics of source-load fluctuations, including calculation of new energy ramp-up coverage, identification of ramp-up relief / aggravation periods, and quantitative calculation of ramp-up demand relief / aggravation rate. Define the coupling relationship between new energy and load fluctuations, accurately identify ramp-up demand relief / aggravation periods, and quantitatively calculate the relationship between ramp-up demand relief rate and aggravation rate. S2. Construct a multi-dimensional evaluation index system for the ramping demand of a new type of power system, including short-term ramping rate demand, continuous ramping time, continuous ramping capacity, and continuous ramping rate, and form a closed-loop evaluation model that deeply integrates the instantaneous response-long-term maintenance time dimension and the capacity scale-rate intensity characteristic dimension suitable for the new type of power system.

2. The novel multi-dimensional assessment method for power system ramping demand considering source-load fluctuation coupling characteristics according to claim 1, characterized in that, The formula for calculating the coverage rate of new energy vehicle ramp-up is as follows: ； in, Let t be the magnitude of the new energy ramp-up coverage rate, which characterizes the fluctuation coupling relationship between new energy fluctuations and load fluctuations; and These represent the load ramp-up and the new energy ramp-up at time t, respectively. when When the value is greater than 1, it indicates that the fluctuation of new energy sources and the fluctuation of loads fluctuate in the same direction, and the fluctuation of new energy sources completely covers the fluctuation of loads with a surplus. when When =1, it means that the fluctuation of new energy sources and the fluctuation of loads fluctuate in the same direction, and the fluctuation of new energy sources completely covers the fluctuation of loads. When 0 < When <1, it indicates that the fluctuation of new energy sources and the fluctuation of load fluctuate in the same direction, and the fluctuation of new energy sources can only cover part of the fluctuation of load. When -1 < When the value is less than 0, it indicates that the fluctuation of new energy sources is opposite to the fluctuation of load, and the intensity of the fluctuation of new energy sources is lower than that of the fluctuation of load. when When ≤-1, it indicates that the fluctuation of new energy sources fluctuates in the opposite direction to the fluctuation of load, and the intensity of the fluctuation of new energy sources exceeds that of the fluctuation of load.

3. A novel multi-dimensional assessment method for power system ramping demand considering source-load fluctuation coupling characteristics, as described in claim 2, is characterized in that... The identification of the hill-climb relief / aggravation period is specifically as follows: (1) Period of reduced demand for hill climbing: Period of easing demand for hill climbing Use new energy ramp coverage Characterization: ; When the coverage rate of new energy ramp-up during a certain period Satisfy 0 < When the value is less than 1, the actual ramp-up demand of the system after the coupling of new energy fluctuations and load fluctuations is less than the traditional load ramp-up demand. When =1, the actual system ramp-up requirement is 0; 1 < The actual ramping demand caused by excess fluctuations at time <2 is still less than the traditional load ramping demand; (2) Periods of heightened demand for hill climbing: Period of heightened demand for hill climbing use Characterization: ; When the coverage rate of new energy ramp-up <0, the actual ramping demand after the coupling of new energy fluctuations and load fluctuations must be greater than the traditional load ramping demand; when ≥2, actual climbing requirements are greater; (3) Identification of climbing periods: By obtaining the temporal distribution of climbing relief / intensification periods, climbing relief / intensification periods can be distinguished. ； in, For the i-th climbing period, As an indicator function, when t i ∈T r When t is taken as 1, i ∈T a Take -1.

4. A novel multi-dimensional assessment method for power system ramping demand considering source-load fluctuation coupling characteristics, as described in claim 3, is characterized in that... The hill-climbing demand mitigation rate / aggravation rate, where: Climbing demand relief rate This refers to the ratio of the total reduction in ramp-up demand during periods of reduced ramp-up demand due to renewable energy output to the total ramp-up demand of traditional loads when there is no renewable energy. ； Increased demand for hill climbing This refers to the ratio of the total increase in ramp-up demand during periods of heightened demand due to renewable energy output to the total ramp-up demand of traditional loads when there is no renewable energy: 。 5. A novel multi-dimensional assessment method for power system ramping demand considering source-load fluctuation coupling characteristics, as described in claim 4, is characterized in that... The short-term climbing rate requirement is measured by the coverage rate of new energy climbing. Characterization: ； in, Let be the system's ramp capacity requirement at time t; To meet the climbing speed requirements, when When the value is greater than 0, it represents the required uphill speed, denoted as . ,when When <0, it represents the downhill climbing rate requirement, denoted as .

6. A novel multi-dimensional assessment method for power system ramping demand considering source-load fluctuation coupling characteristics, as described in claim 5, is characterized in that... The continuous ramp time is the total duration of a single unidirectional ramp demand from start to finish during power system operation. It characterizes the system's long-term maintenance capability requirements for various regulatory resources, and the formula is as follows: ； in, and These represent the duration of the nth continuous uphill / downhill phase of the system, respectively. and These are the end time and start time of the nth continuous uphill period of the system, respectively; and These are the end time and start time of the nth continuous downhill climbing period of the system, respectively.

7. A novel multi-dimensional assessment method for power system ramping demand considering source-load fluctuation coupling characteristics as described in claim 6, characterized in that, The total capacity required by the continuous climbing capacity characterization system during a single unidirectional climbing period is given by the following formula: ； in, This represents the continuous uphill capacity requirement during the nth uphill period. This represents the continuous downhill capacity requirement during the nth downhill period. The total unidirectional ramp capacity requirement during the day is represented as the sum of the system's unidirectional ramp capacity requirements to meet the power balance during the day, as shown in the following formula: ； in, This represents the total capacity demand for the day's upward climb. This represents the total capacity demand during the day's downhill climb. Calculate the intraday ramp capacity gap: ; Wherein, ΔC represents the intraday ramp capacity gap; If the intraday ramp capacity gap is greater than 0, it means that the total ramp capacity demand is greater than the total ramp capacity demand, and energy input type regulation resources need to be configured. If the intraday ramp capacity gap is equal to 0, then the total ramp capacity demand and the total ramp capacity demand are equal, and energy transfer type adjustment resources need to be configured. If the intraday ramp capacity gap is less than 0, it means that the total ramp capacity demand is less than the total ramp capacity demand, and energy absorption type regulation resources need to be configured.

8. A novel multi-dimensional assessment method for power system ramping demand considering source-load fluctuation coupling characteristics, as described in claim 7, is characterized in that... The sustained ramp rate is the average rate of change of the system's required adjustment power per unit time during a complete sustained ramp event, as shown in the following formula: ； in, This represents the required rate of increase for the nth continuous uphill period. This represents the required rate of descent during the nth continuous descent period.

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