A performance-based power system resilience assessment method and device

Abstract

The present invention relates to the technical field of power systems, and discloses a performance-based power system resilience assessment method and device. The present invention proposes four characteristics that the resilience index needs to meet, and on this basis constructs a new performance-based resilience index, which integrates multiple factors such as the occurrence and impact time of interference, the effort to balance power supply and demand, the size and trend of the resilience curve, the duration of the interruption, and the importance of the load. By constructing a more reasonable resilience index and evaluating the resilience of the power system based on the above resilience index, the different impacts of interference can be distinguished more accurately, so as to solve the problem that the existing resilience index is unreasonable in definition, resulting in poor or even ineffective evaluation results in some cases.

Description

Technical Field

[0001] The present invention relates to the technical field of power systems, and in particular to a performance-based power system resilience assessment method and device. Background Art

[0002] The power system is vulnerable to the impacts of climate change. Climate-related risks will affect all aspects of the power system, such as damaging infrastructure, interrupting system operations, and causing major changes in electricity supply and demand. What is more serious is that as climate change intensifies, the frequency, scope, severity and duration of climate-related risks are expected to increase further, which will undoubtedly bring unprecedented challenges to the safe and reliable operation of the power system. From a theoretical point of view, the system's ability to cope with external shocks such as reliability, stability and recoverability is usually defined as resilience. Considering that the risk of power outages caused by climate events cannot be completely eliminated, the impact of these factors can be reduced by increasing the resilience of the system. Therefore, enhancing the resilience of the power system has become a key strategy for its effective response to climate-related risks, and building a resilient power system is imperative.

[0003] At present, resilient power systems have been widely accepted by all countries. Resilience theory has been applied to different levels of power systems (such as global, regional and community), different components (such as general power systems, microgrids, transmission systems, distribution systems) and different purposes (such as planning, unit allocation, and scheduling) and has become one of the research hotspots in recent years. Many researchers have studied the assessment framework of resilience and proposed various strategies to improve the resilience of power systems, such as planning strategies before disturbances, real-time operation strategies during disturbances, and recovery strategies after disturbances.

[0004] As the premise and basis for power system resilience assessment, resilience indicators play an important role in resilience-related research. In existing studies, most resilience indicators are based on the performance changes of power systems (resilience curves) and are defined by considering the total or average performance loss during the disturbance impact time. However, this method cannot capture some important resilience characteristics, such as the speed and duration of system performance degradation / recovery, resulting in poor or even ineffective indicators in some cases, especially when the total performance loss of the power system under different disturbances is the same or the system has the same resilience improvement performance. An important reason is that the characteristics of resilience indicators have not been fully analyzed and reflected, which will affect the rationality of the construction of resilience indicators and the accuracy of the evaluation. Summary of the invention

[0005] In view of this, the present invention provides a performance-based power system resilience assessment method and device to solve the problem that the existing resilience indicators are unreasonable in definition, resulting in poor or even invalid assessment results in some cases.

[0006] In a first aspect, the present invention provides a performance-based power system resilience assessment method, the method comprising:

[0007] Constructing a power system resilience index, wherein the resilience index includes the following characteristics: a time range including the occurrence and impact time of the disturbance, quantifying the efforts made by the power system to balance power supply and demand, reflecting the size and trend of the resilience curve, and reflecting the nonlinear relationship between the interruption duration / load importance and resilience;

[0008] Assessing the resilience of the power system based on the resilience indicators;

[0009] The toughness index is compared with existing commonly used toughness indexes to determine the rationality of the toughness index.

[0010] The present invention provides a performance-based power system resilience assessment method, proposes four characteristics that resilience indicators need to meet, and establishes a new performance-based resilience indicator on this basis, which integrates multiple factors such as the occurrence and impact time of interference, the effort to balance power supply and demand, the size and trend of the resilience curve, the duration of the interruption and the importance of the load. By constructing a more reasonable resilience indicator and evaluating the resilience of the power system based on the above resilience indicator, the different impacts of interference can be distinguished more accurately to solve the problem that the existing resilience indicator definition is unreasonable, resulting in poor or even invalid evaluation results in some cases.

[0011] In an optional implementation, evaluating the resilience of the power system based on the resilience indicator includes:

[0012] During the occurrence and impact time of the disturbance, the resilience curve is obtained based on the power supply and power demand of the power system;

[0013] According to a first preset formula, calculating a time set of interference;

[0014] According to the second preset formula, calculating the change of the toughness curve;

[0015] According to a third preset formula, calculating the interruption duration of the power system under interference;

[0016] Calculating the impact of power system interruption according to a fourth preset formula;

[0017] According to the fifth preset formula, the number of time points at which the performance of the power system increases continuously and monotonically is calculated;

[0018] According to a sixth preset formula, the number of time points at which the performance of the power system continuously and monotonically decreases is calculated;

[0019] According to the seventh preset formula, the change trend of the toughness curve is calculated;

[0020] According to the eighth preset formula, the resilience of the power system is calculated.

[0021] In an optional implementation manner, the eighth preset formula is as follows:

[0022]

[0023] Among them, R j (u,w j ) is the power system j under disturbance u and operation condition w j Toughness under t (u,w j ) is the toughness curve, l t (u,w j )=max{d t (u,w j )-s t (u,w j ),0},d t (u,w j ) is the power system j under disturbance u and operation condition w j The power demand under t (u,w j ) is the power system j under disturbance u and operation condition w j The power supply under the condition of t0 is the time set x u The start time of N is the time set χ u End time of t is the changing trend of the toughness curve at time t; β t is the change of the toughness curve at time t; γ t is the impact of power system interruption at time t.

[0024] In an optional implementation manner, the first preset formula is as follows:

[0025]

[0026] Among them, χ u is the time set under disturbance u, t∈χ u ; t1 is the time when the interference occurs, defined as u normal is the normal situation, ε is the critical threshold; t2 is the impact time of the interference, defined as l t (u,w j )>0.

[0027] In an optional implementation manner, the second preset formula is as follows:

[0028]

[0029] Among them, β t is the change of the toughness curve at time t; l t is the toughness curve at time t; l t-1 is the toughness curve at time t-1.

[0030] In an optional implementation, the fourth preset formula is as follows:

[0031] γ t =ln(f t +1)

[0032] Among them, f t is the duration of the power system interruption until time t.

[0033] In an optional implementation manner, the seventh preset formula is as follows:

[0034]

[0035] Among them, g t h is the number of time points at which the power system performance continues to increase monotonically until time t; t is the number of time points at which the power system performance continuously and monotonically decreases until time t; l t+1 is the toughness curve at time t+1.

[0036] In a second aspect, the present invention provides a performance-based power system resilience assessment device, the device comprising:

[0037] A construction module is used to construct a power system resilience index, wherein the resilience index includes the following characteristics: a time range including the occurrence and impact time of the disturbance, quantifying the efforts made by the power system to balance the supply and demand of electricity, reflecting the size and trend of the resilience curve, and reflecting the nonlinear relationship between the interruption duration / load importance and resilience;

[0038] An evaluation module, configured to evaluate the resilience of the power system based on the resilience indicator;

[0039] The comparison module is used to compare the toughness index with the existing commonly used toughness index to determine the rationality of the toughness index.

[0040] The present invention provides a performance-based power system resilience assessment device and establishes a new performance-based resilience index, which integrates multiple factors such as the occurrence and impact time of interference, the effort to balance power supply and demand, the size and trend of the resilience curve, the duration of the interruption and the importance of the load. By constructing a more reasonable resilience index and evaluating the resilience of the power system based on the above resilience index, it is possible to more accurately distinguish the different impacts of interference, so as to solve the problem that the existing resilience index is unreasonable in definition, resulting in poor or even invalid evaluation results in some cases.

[0041] In a third aspect, the present invention provides a computer device, comprising: a memory and a processor, the memory and the processor being communicatively connected to each other, the memory storing computer instructions, and the processor executing the performance-based power system resilience assessment method of the first aspect or any corresponding embodiment thereof by executing the computer instructions.

[0042] In a fourth aspect, the present invention provides a computer-readable storage medium having computer instructions stored thereon, the computer instructions being used to enable a computer to execute the performance-based power system resilience assessment method of the above-mentioned first aspect or any corresponding embodiment thereof. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0044] Figure 1 is a flow chart of a performance-based power system resilience assessment method according to an embodiment of the present invention;

[0045] Figure 2 is a resilience curve of a power system during a snowstorm according to an embodiment of the present invention;

[0046] Figure 3 is a resilience curve of a power system under different disturbances according to an embodiment of the present invention;

[0047] Figure 4 is a structural block diagram of a performance-based power system resilience assessment device according to an embodiment of the present invention;

[0048] Figure 5 It is a schematic diagram of the hardware structure of a computer device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0049] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are 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 those skilled in the art without creative work are within the scope of protection of the present invention.

[0050] As the premise and basis for power system resilience assessment, resilience indicators play an important role in resilience-related research. Sandia National Laboratories proposed eight requirements for power system resilience indicators: usefulness, comparability, usability in operational and planning environments, scalability, quantification, reflection of uncertainty, support for risk-based approaches, and consideration of recovery time. Among them, the most basic requirements are quantification, comparability, and temporal and spatial scalability. However, existing performance-based indicators do not adequately analyze and reflect the various characteristics of resilience curves, resulting in these indicators being less effective or even ineffective in some cases, especially when the total performance loss of the power system under different disturbances is the same or the improved performance of the two power systems is the same. An important reason is that the characteristics of resilience indicators have not been fully analyzed and reflected, which will affect the rationality of the construction of resilience indicators and the accuracy of the evaluation.

[0051] To this end, an embodiment of the present invention provides a performance-based power system resilience assessment method, which establishes a new performance-based resilience indicator and evaluates the resilience of the power system based on the indicator to solve the problem that the existing resilience indicators are unreasonable in definition, resulting in poor or even invalid assessment results in some cases.

[0052] According to an embodiment of the present invention, an embodiment of a performance-based power system resilience assessment method is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0053] In this embodiment, a performance-based power system resilience assessment method is provided. Figure 1 is a flow chart of a performance-based power system resilience assessment method according to an embodiment of the present invention. Figure 1 As shown, the process includes the following steps:

[0054] Step S11, constructing a power system resilience index, the resilience index includes the following characteristics: the time range includes the occurrence and impact time of the disturbance, quantifies the efforts made by the power system to balance the supply and demand of electricity, reflects the size and trend of the resilience curve, and reflects the nonlinear relationship between the interruption duration / load importance and resilience.

[0055] Specifically, firstly, most resilience indicators only consider the impact time of the disturbance, but not the occurrence time of the disturbance, so that the efforts made by the power system to maintain the balance of power supply and demand are not fully quantified, resulting in inaccurate evaluation results. In practice, many factors affect the ability of the power system to mitigate the impact of disturbances, such as infrastructure (such as backup generators, material types of infrastructure) and related operations (such as generator rescheduling, topology switching and other facility adjustments). When a disturbance occurs, the system performance may not decline for a period of time. This process is also an important manifestation of system resilience and should be quantified. Secondly, performance-based resilience indicators are usually based on the resilience curve of the power system, but the characteristics of the resilience curve (such as trend and size) are not accurately characterized, resulting in the inability of the indicators to distinguish the different impacts of the disturbance, especially when the total performance loss of the two resilience curves is the same. Thirdly, there is a complex nonlinear relationship between resilience and various factors (such as the duration of the interruption), and a relatively accurate characterization of the above relationship has a great impact on the reasonable construction of resilience indicators. Based on the above discussion, it is crucial to reasonably analyze the resilience characteristics and establish reasonable indicators on this basis.

[0056] In response to the problems of unreasonable definitions of existing resilience indicators and poor or even ineffective evaluation results in some cases, the embodiment of the present application, based on the analysis of the resilience curve, proposes four characteristics of resilience indicators and establishes a new performance-based resilience indicator. This metric integrates the occurrence and impact time of interference, the efforts made by the power system to balance the supply and demand of electricity, the size and trend of the resilience curve, and the nonlinear relationship between the interruption duration / load importance and resilience.

[0057] Among them, feature 1: The time range of resilience indicators should include the occurrence and impact time of the disturbance. Disturbances may not affect the performance of the power system immediately, so if the occurrence time of the disturbance is not considered, the system resilience in the absorption stage cannot be quantified. After the disturbance occurs, due to the delayed impact, the power supply cannot meet the power demand, and the power system must go through the response and recovery stages to reach a new stable state. Therefore, ignoring the impact time of the disturbance will lead to the inability to quantify the resilience in the response and recovery stages.

[0058] Feature 2: Resilience indicators should quantify the efforts made by the power system to balance power supply and demand. When a disturbance occurs, the power system will take a series of measures to ensure that supply and demand are balanced as much as possible. These measures can effectively mitigate the impact of the disturbance and keep power supply and demand balanced. However, these efforts may also fail to mitigate the impact of the disturbance and lead to load shedding. Both results reflect the resilience of the power system and must be quantified at the same time to ensure rationality.

[0059] Feature 3: The resilience index should reflect the size and trend of the resilience curve. The result of the competition between the impact of the disturbance and the efforts of the power system will be reflected in the system performance and then in the resilience curve. The resilience curve of the power system is fluctuating, and its trend and size can reflect the pressure of the disturbance on the power system. The flatter the trend of the resilience curve, the less pressure the disturbance puts on the dispatching strategy, and the greater the resilience of the power system. In actual applications, the trend and size of the resilient power system may not all be better than other systems. Therefore, it is necessary to comprehensively consider the trend and size and establish an indicator that satisfies the total order relationship to ensure comparability.

[0060] Feature 4: Resilience indicators should consider the nonlinear relationship between interruption duration / load importance and resilience. The longer the interruption duration, the greater the critical load shedding at a certain moment, the greater the power outage loss caused by the disturbance, and the lower the resilience of the power system. For example, the critical load directly affects the ability of the power system to maintain critical operations, so critical load shedding will cause more serious impacts than non-critical load shedding. Therefore, interruption duration and load importance can reflect the resilience of the power system, and their nonlinear relationship with resilience must be quantified to make the results more in line with reality.

[0061] The resilience index should satisfy the four characteristics ignored by the previous index to make it more reasonable. In order to satisfy characteristic 1, the time range is divided into two parts. The first is the time when the disturbance occurs, defined as |uu normal |≥ε.u normal is the normal situation, ε is the critical threshold. The second is the impact time of the interference, which is defined as l t (u,w j )>0. In order to meet feature 2, the reduction of power demand on the demand side and the increase of power supply on the supply side are used to reflect the efforts of the power system to maintain system resilience. The reduction of power demand can be characterized by load reduction, and the increase of power supply can be characterized by the average power supply without interference and the actual power supply under interference. In order to meet feature 3, the number of time points at which the power system performance continues to increase monotonically and decrease monotonically until time t is used, that is, g t and h tTo describe the changing trend of the resilience curve at time t. The difference in performance between time t-1 and time t is used to describe the change in the resilience curve at time t. In order to meet feature 4, the relationship between power outage duration / load reduction and power outage cost should be reflected. Related studies have shown that the power outage cost of the power system increases with the increase of load shedding, and its change tends to increase rapidly first and then slow down. This nonlinear relationship can be characterized by an exponential function, which has been used to construct some resilience indicators of the power system. In addition, related studies have shown that the power outage cost of the power system is high initially, but as the power outage time increases, the cost drops rapidly, and this relationship can be characterized by a logarithmic function. Therefore, an exponential function / natural logarithm function is used to represent the nonlinear relationship between power outage cost and load importance / interruption duration.

[0062] Step S12, evaluating the resilience of the power system based on the resilience index.

[0063] Specifically, the above step S12 includes:

[0064] Step S121, obtaining a resilience curve based on power supply and power demand of the power system during the occurrence and impact time of the interference.

[0065] Specifically, according to formula l t (u,w j )=max{d t (u,w j )-s t (u,w j ),0}, using the power system disturbance u and operation status w at time t j The power supply and power demand under the condition are given by the resilience curve l t (u,w j ). Among them, d t (u,w j ) is the power system j under disturbance u and operation condition w j The power demand under t (u,w j ) is the power system j under disturbance u and operation condition w j The power supply below.

[0066] Step S122: Calculate the time set under interference according to the first preset formula.

[0067] Specifically, the first preset formula is as follows:

[0068]

[0069] Among them, χ u is the time set under disturbance u, t∈χ u ; t1 is the time when the interference occurs, defined as u normal is the normal situation, ε is the critical threshold; t2 is the impact time of the interference, defined as l t (u,w j )>0.

[0070] Step S123, calculating the change of the toughness curve according to the second preset formula.

[0071] Specifically, the second preset formula is as follows:

[0072]

[0073] Among them, β t is the change of the toughness curve at time t; l t is the toughness curve at time t; l t-1 is the toughness curve at time t-1.

[0074] Step S124, calculating the interruption duration of the power system under interference according to a third preset formula.

[0075] Specifically, the third preset formula is as follows:

[0076]

[0077] Among them, f t is the duration of the power system interruption until time t; f t-1 is the duration of the power system interruption until time t-1.

[0078] Step S125, calculating the impact of the power system interruption according to a fourth preset formula.

[0079] Specifically, the fourth preset formula is as follows:

[0080] γ t =ln(f t +1)

[0081] Among them, γ t is the impact of power system interruption at time t.

[0082] Step S126, calculating the number of time points at which the power system performance increases continuously and monotonically according to the fifth preset formula.

[0083] Specifically, the fifth preset formula is as follows:

[0084]

[0085] Among them, g t g is the number of time points at which the power system performance continues to increase monotonically until time t; t-1is the number of time points at which the power system performance continues to increase monotonically until time t-1.

[0086] Step S127, calculating the number of time points at which the power system performance continuously and monotonically decreases according to the sixth preset formula.

[0087] Specifically, the sixth preset formula is as follows:

[0088]

[0089] Among them, h t is the number of time points at which the power system performance continuously and monotonically decreases until time t; h t-1 is the number of time points at which the power system performance continues to decline monotonically until time t-1.

[0090] Step S128, calculating the change trend of the toughness curve according to the seventh preset formula.

[0091] Specifically, the seventh preset formula is as follows:

[0092]

[0093] Among them, l t+1 is the toughness curve at time t+1.

[0094] Step S129, calculating the resilience of the power system according to the eighth preset formula.

[0095] Specifically, the eighth preset formula is as follows:

[0096]

[0097] Among them, R j (u,w j ) is the power system j under disturbance u and operation condition w j Toughness under t (u,w j ) is the toughness curve, l t (u,w j )=max{d t (u,w j )-s t (u,w j ),0},d t (u,w j ) is the power system j under disturbance u and operation condition w j The power demand under t (u,w j ) is the power system j under disturbance u and operation condition w j The power supply under the condition of t0 is the time set x u The start time ofN is the time set χ u End time of t is the changing trend of the toughness curve at time t; β t is the change of the toughness curve at time t; γ t is the impact of power system interruption at time t.

[0098] The theoretical value range of power system resilience is The larger the value, the stronger the resilience of the power system. According to the eighth preset formula, the worst case is that in [t0,t N ], the power supply is always zero, that is, all generators are tripped or unable to start. In this case, l t (u,w j ) = d t (u,w j ). The best case is that the interruption duration is 0. In other words, the increase in power demand caused by the interruption can be met by backup equipment, power purchase, etc. In this case, the resilience is 0. In order to show the results more clearly and facilitate comparative analysis, the range of the resilience index is uniformly converted to [0,1].

[0099] This embodiment aims to calculate the resilience of a test system under different disturbances (such as a snowstorm) and clearly explain how to calculate the different parameters of the resilience indicator. In the hypothetical power system, it is assumed that the supply and demand of the power system under normal conditions is 0.6GW. Subsequently, a snowstorm occurred at time 1, and the temperature was below the critical threshold, thereby increasing the demand for electricity. Although the system has taken a series of measures to ensure the balance between supply and demand as much as possible, the demand for electricity continues to increase, and load shedding occurs at time 2. Assume that the snowstorm ends at time 5, but its impact still exists until the system returns to normal at time 7. Figure 2 The figure shows the resilience curve of the power system during the storm.

[0100] According to the first preset formula, the occurrence time of interference is from time 1 to time 5, and the impact time is from time 2 to time 7. Therefore, the calculation method of the time range is to take the union of the occurrence time and the impact time, so t0 = 1 and t N =7. Figure 2The load rejection line in the middle represents the toughness curve in each time period; therefore, l = (0, 0, 0.2, 0.1, 0.2, 0.1, 0). The size of the toughness curve can also be calculated accordingly, that is, β = (1, 1, 1.2, 1.1, 1.1, 1.1, 1.1). According to the fifth preset formula and the sixth preset formula, the continuous growth and decline trend of the system performance in each time period can be calculated, that is, h = (0, 0, 0, 1, 0, 1, 2) and g = (0, 0, 1, 0, 1, 0, 0). According to the seventh preset formula, the change trend of the toughness curve can be calculated, that is, α = (1, 1, 1.17, 1.17, 1.17, 1.33). Since the interruption starts at 2 o'clock and ends at 7 o'clock, the duration of the interruption at different times can be calculated according to the third preset formula, that is, f = (0, 0, 1, 2, 3, 4, 0); at the same time, the impact of the interruption duration is obtained, that is, γ = (0, 0, 0.63, 1.10, 1.39, 1.61, 0). According to the eighth preset formula, the resilience of the hypothetical power system under the wind disaster can be calculated, which is equal to -1.20. Repeat this process for power demand and calculate the lower limit of resilience; finally, the resilience after conversion to the [0, 1] range is 0.77.

[0101] Step S13, comparing the toughness index with existing commonly used toughness indexes to determine the rationality of the toughness index.

[0102] Specifically, compared with previous performance-based toughness indices, the proposed index considers the time range of the toughness curve (χ u ), the trend and size of the toughness curve change (α t and β t ), the impact of interruption duration (γ t ) and the importance of load Since it is generally believed that the impact of interruption duration gradually increases and critical loads are more important, the rationality of introducing interruption duration and load importance can be intuitively reflected. The impact of introducing the interference occurrence time and the trend and size of the analysis curve cannot be observed intuitively. Therefore, three hypothetical situations are designed to quantitatively analyze the introduction of α t , β t and χ u The rationality of Figure 3 ). Specifically, scenarios ac reflect different sizes, trends and time frames of the resilience curve.

[0103] For scenario a, the maximum performance degradation and performance variation caused by disturbance 1 are smaller than those caused by disturbance 2, so the pressure on the dispatch strategy is smaller. Some operation control strategies (such as optimized topology reconfiguration or backup power operation) can be adjusted to make the power system performance degrade slower and smaller. Therefore, the system is more resilient under disturbance 1. For scenario b, the longest time that system performance continues to degrade due to disturbance 1 is 2 hours, while it is 3 hours in the case of disturbance 2. The shorter the time of continuous performance degradation, the less pressure it puts on the dispatch strategy, so the system is more resilient under disturbance 1. For scenario c, the efforts of the power system under disturbance 1 are significant, ensuring the balance of power supply and demand before time 3. This good result shows that the system is more resilient under disturbance 1.

[0104] In order to verify the rationality of the proposed toughness index, the present invention selected six commonly used performance-based toughness indexes (see Table 1). The details are as follows:

[0105] Metric 1: Difference between ideal performance level and actual performance level.

[0106] Indicator 2: Total load shedding at each time point.

[0107] Indicator 3: The unit time difference between the ideal operating level and the actual operating level.

[0108] Indicator 4: Mean value of the probability density function of the consequences.

[0109] Indicator 5: The area ratio between the actual performance curve and the ideal performance curve.

[0110] Metric 6: Corrected load loss probability.

[0111] Table 1 shows that the resilience calculated by indicators 1-6 is equal in all cases, which indicates that indicators 1-6 cannot accurately distinguish the resilience of the system under disturbance 2 and disturbance 1. The difference in resilience calculated by indicators 1-6 is small, which is caused by the difference between trapezoidal numerical integration and summation. The main reason is that indicators 1-6 only consider the impact time of the disturbance, the imbalance between supply and demand, and the area of ​​performance degradation. However, factors such as the time range of the disturbance, the efforts made by the system to balance the supply and demand of electricity, the size and change trend of the resilience curve, and the duration of the interruption / load importance cannot be quantified. The indicators proposed in this application can more accurately distinguish the above characteristics of the resilience curve under different disturbances, thereby making the evaluation results more reasonable.

[0112] Table 1: Comparison of system resilience under different scenarios

[0113]

[0114] The embodiment of the present invention verifies the rationality of the proposed indicator by assuming a case and comparing it with existing commonly used resilience indicators. At the same time, the embodiment of the present invention provides a universal quantitative indicator that can be extended to other types of interference, and provides a basis for formulating reasonable resilience improvement goals and specific resilience improvement strategies.

[0115] The present invention provides a performance-based power system resilience assessment method, proposes four characteristics that resilience indicators need to meet, and establishes a new performance-based resilience indicator on this basis, which integrates multiple factors such as the occurrence and impact time of interference, the effort to balance power supply and demand, the size and trend of the resilience curve, the duration of the interruption and the importance of the load. By constructing a more reasonable resilience indicator and evaluating the resilience of the power system based on the above resilience indicator, the different impacts of interference can be distinguished more accurately to solve the problem that the existing resilience indicator definition is unreasonable, resulting in poor or even invalid evaluation results in some cases.

[0116] In this embodiment, a performance-based power system resilience assessment device is also provided, which is used to implement the above-mentioned embodiments and preferred implementation modes, and will not be repeated hereafter. As used below, the term "module" may be a combination of software and / or hardware that implements a predetermined function. Although the devices described in the following embodiments are preferably implemented in software, the implementation in hardware, or a combination of software and hardware, is also possible and conceivable.

[0117] This embodiment provides a performance-based power system resilience assessment device, such as Figure 4 As shown, including:

[0118] Construction module 41 is used to construct a power system resilience index, which includes the following characteristics: the time range includes the occurrence and impact time of the disturbance, quantifies the efforts made by the power system to balance the supply and demand of electricity, reflects the size and trend of the resilience curve, and reflects the nonlinear relationship between the interruption duration / load importance and resilience.

[0119] An evaluation module 42, for evaluating the resilience of the power system based on the resilience index;

[0120] The comparison module 43 is used to compare the toughness index with existing commonly used toughness indexes to determine the rationality of the toughness index.

[0121] The further functional description of each of the above modules and units is the same as that of the above corresponding embodiments and will not be repeated here.

[0122] The performance-based power system resilience assessment device in this embodiment is presented in the form of a functional unit, where the unit refers to an ASIC (Application Specific Integrated Circuit) circuit, a processor and memory that executes one or more software or fixed programs, and / or other devices that can provide the above functions.

[0123] The present invention provides a performance-based power system resilience assessment device and establishes a new performance-based resilience index, which integrates multiple factors such as the occurrence and impact time of interference, the effort to balance power supply and demand, the size and trend of the resilience curve, the duration of the interruption and the importance of the load. By constructing a more reasonable resilience index and evaluating the resilience of the power system based on the above resilience index, it is possible to more accurately distinguish the different impacts of interference, so as to solve the problem that the existing resilience index is unreasonable in definition, resulting in poor or even invalid evaluation results in some cases.

[0124] The embodiment of the present invention also provides a computer device having the above Figure 4 The performance-based power system resilience assessment device shown.

[0125] See also Figure 5 , Figure 5 is a schematic diagram of the structure of a computer device provided by an optional embodiment of the present invention, such as Figure 5 As shown, the computer device includes: one or more processors 10, a memory 20, and interfaces for connecting various components, including high-speed interfaces and low-speed interfaces. Various components are connected to each other using different buses for communication, and can be installed on a common mainboard or installed in other ways as needed. The processor can process the instructions executed in the computer device, including instructions stored in or on the memory to display the graphical information of the GUI on an external input / output device (such as, a display device coupled to the interface). In some optional embodiments, if necessary, multiple processors and / or multiple buses can be used together with multiple memories and multiple memories. Similarly, multiple computer devices can be connected, and each device provides some necessary operations (for example, as a server array, a group of blade servers, or a multi-processor system). Figure 5 A processor 10 is taken as an example.

[0126] The processor 10 may be a central processing unit, a network processor or a combination thereof. The processor 10 may further include a hardware chip. The hardware chip may be a dedicated integrated circuit, a programmable logic device or a combination thereof. The programmable logic device may be a complex programmable logic device, a field programmable gate array, a general purpose array logic or any combination thereof.

[0127] The memory 20 stores instructions executable by at least one processor 10, so that the at least one processor 10 executes the method shown in the above embodiment.

[0128] The memory 20 may include a program storage area and a data storage area, wherein the program storage area may store an operating system, an application required for at least one function; the data storage area may store data created according to the use of the computer device, etc. In addition, the memory 20 may include a high-speed random access memory, and may also include a non-transient memory, such as at least one disk storage device, a flash memory device, or other non-transient solid-state storage device. In some optional embodiments, the memory 20 may optionally include a memory remotely arranged relative to the processor 10, and these remote memories may be connected to the computer device via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0129] The memory 20 may include a volatile memory, such as a random access memory; the memory may also include a non-volatile memory, such as a flash memory, a hard disk or a solid state drive; the memory 20 may also include a combination of the above types of memory.

[0130] The computer device further comprises a communication interface 30 for the computer device to communicate with other devices or a communication network.

[0131] The embodiment of the present invention also provides a computer-readable storage medium. The method according to the embodiment of the present invention can be implemented in hardware, firmware, or can be implemented as a computer code that can be recorded in a storage medium, or can be implemented as a computer code that is originally stored in a remote storage medium or a non-temporary machine-readable storage medium and will be stored in a local storage medium through a network download, so that the method described herein can be stored in such software processing on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. Among them, the storage medium can be a magnetic disk, an optical disk, a read-only storage memory, a random access memory, a flash memory, a hard disk or a solid-state hard disk, etc.; further, the storage medium can also include a combination of the above types of memories. It can be understood that a computer, a processor, a microprocessor controller, or programmable hardware includes a storage component that can store or receive software or computer code. When the software or computer code is accessed and executed by a computer, a processor, or hardware, the method shown in the above embodiment is implemented.

[0132] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A performance-based power system resilience assessment method, characterized in that: The method comprises: Constructing a power system resilience index, wherein the resilience index includes the following characteristics: a time range including the occurrence and impact time of the disturbance, quantifying the efforts made by the power system to balance power supply and demand, reflecting the size and trend of the resilience curve, and reflecting the nonlinear relationship between the interruption duration / load importance and resilience; Assessing the resilience of the power system based on the resilience indicators; Compare the toughness index with existing commonly used toughness indexes to determine the rationality of the toughness index; The resilience of the power system is evaluated based on the resilience indicators, including: During the occurrence and impact time of the disturbance, the resilience curve is obtained based on the power supply and power demand of the power system; According to a first preset formula, calculating a time set of interference; According to the second preset formula, calculating the change of the toughness curve; According to a third preset formula, calculating the interruption duration of the power system under interference; Calculating the impact of power system interruption according to a fourth preset formula; According to the fifth preset formula, the number of time points at which the performance of the power system increases continuously and monotonically is calculated; According to a sixth preset formula, the number of time points at which the performance of the power system continuously and monotonically decreases is calculated; According to the seventh preset formula, the change trend of the toughness curve is calculated; According to the eighth preset formula, the resilience of the power system is calculated; The eighth preset formula is as follows: Among them, R j (u,w j ) is the power system j under disturbance u and operation condition w j Toughness under t (u,w j ) is the toughness curve, l t (u,w j )=max{d t (u,w j )-s t (u,w j ),0},d t (u,w j ) is the power system j under disturbance u and operation condition w j The power demand under t (u,w j ) is the power system j under disturbance u and operation condition w j The power supply under the condition of t0 is the time set x u The start time of N is the time set χ u End time of t is the changing trend of the toughness curve at time t; β t is the change of the toughness curve at time t; γ t is the impact of power system interruption at time t.

2. The performance-based power system resilience assessment method according to claim 1, characterized in that: The first preset formula is as follows: Among them, χ u is the time set of interference u, t∈χ u ; t1 is the time when the interference occurs, defined as u normal is the normal situation, ε is the critical threshold; t2 is the impact time of the interference, defined as l t (u,w j )>0.

3. The performance-based power system resilience assessment method according to claim 1, characterized in that: The second preset formula is as follows: Among them, β t is the change of the toughness curve at time t; l t is the toughness curve at time t; l t-1 is the toughness curve at time t-1.

4. The performance-based power system resilience assessment method according to claim 1, characterized in that: The fourth preset formula is as follows: c t =ln(f t +1) Among them, f t is the duration of the power system interruption until time t.

5. The performance-based power system resilience assessment method according to claim 1, characterized in that: The seventh preset formula is as follows: Among them, g t h is the number of time points at which the power system performance continues to increase monotonically until time t; t is the number of time points at which the power system performance continuously and monotonically decreases until time t; l t+1 is the toughness curve at time t+1.

6. A performance-based power system resilience assessment device, characterized in that: The device comprises: A construction module is used to construct a power system resilience index, wherein the resilience index includes the following characteristics: a time range including the occurrence and impact time of the disturbance, quantifying the efforts made by the power system to balance the supply and demand of electricity, reflecting the size and trend of the resilience curve, and reflecting the nonlinear relationship between the interruption duration / load importance and resilience; An evaluation module, configured to evaluate the resilience of the power system based on the resilience indicator; A comparison module, used to compare the toughness index with existing commonly used toughness indexes to determine the rationality of the toughness index; The resilience of the power system is evaluated based on the resilience indicators, including: During the occurrence and impact time of the disturbance, the resilience curve is obtained based on the power supply and power demand of the power system; According to a first preset formula, calculating a time set of interference; According to the second preset formula, calculating the change of the toughness curve; According to a third preset formula, calculating the interruption duration of the power system under interference; Calculating the impact of power system interruption according to a fourth preset formula; According to the fifth preset formula, the number of time points at which the performance of the power system increases continuously and monotonically is calculated; According to a sixth preset formula, the number of time points at which the performance of the power system continuously and monotonically decreases is calculated; According to the seventh preset formula, the change trend of the toughness curve is calculated; According to the eighth preset formula, the resilience of the power system is calculated; The eighth preset formula is as follows: Among them, R j (u,w j ) is the power system j under disturbance u and operation condition w j Toughness under t (u,w j ) is the toughness curve, l t (u,w j )=max{d t (u,w j )-s t (u,w j ),0},d t (u,w j ) is the power system j under disturbance u and operation condition w j The power demand under t (u,w j ) is the power system j under disturbance u and operation condition w j The power supply under the condition of t0 is the time set x u The start time of N is the time set χ u End time of t is the changing trend of the toughness curve at time t; β t is the change of the toughness curve at time t; γ t is the impact of power system interruption at time t.

7. A computer device, characterized in that: include: A memory and a processor, wherein the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the performance-based power system resilience assessment method described in any one of claims 1 to 5 by executing the computer instructions.

8. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a computer to execute the performance-based power system resilience assessment method described in any one of claims 1 to 5.

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