A method and terminal for electric vehicle to participate in power grid regulation

Abstract

The present invention provides a method and terminal for electric vehicles to participate in grid regulation, including the following steps: generating a predicted charging power curve for the future based on actual grid operation data; adjusting the electric vehicles in the regional grid to reversely provide electric energy to the grid according to the predicted charging power curve during a preset peak load period, thereby obtaining an adjusted charging power curve; and absorbing the output of new energy according to the adjusted charging power curve. The present invention predicts the charging power curve within a period of time in the future based on the current charging power of the electric vehicle, and at the same time fully utilizes the energy storage characteristics and adjustable characteristics of the electric vehicle to participate in the peak load regulation of the grid, and reversely provides electric energy to the grid during the peak load period, which can not only optimize the energy storage configuration of the grid, effectively realize peak shaving and valley filling, and load balancing of the grid, but also promote the absorption of new energy.

Description

Technical Field

[0001] The present invention relates to the technical field of new energy vehicles, and in particular to a method and a terminal for electric vehicles to participate in power grid regulation. Background Art

[0002] In recent years, wind power and photovoltaics, as green renewable energy sources, have gradually attracted the attention of more and more countries. So far, wind power has become the largest and most technologically mature renewable energy source besides hydropower. With the gradual development of photovoltaics, its installed capacity is also increasing rapidly. In some areas, photovoltaic installed capacity will gradually exceed wind power installed capacity.

[0003] At the same time, electric vehicles (EVs), as a new means of transportation, have developed rapidly due to their advantage of zero emission of polluting gases.

[0004] However, as the number of electric vehicles continues to increase in the future, electric vehicle charging will bring a large amount of load growth to the distribution network, causing increased peak-to-valley differences in distribution network loads, line overloads and other hazards. In order to maintain stable operation, the power grid needs to be equipped with more peak-shaving, frequency-regulating power sources and backup capacity, which reduces the economy of the system.

[0005] At the same time, wind power, photovoltaics and electric vehicles are all random, and their large-scale and simultaneous grid connection will threaten the stable operation of the power system.

[0006] Since electric vehicles have the characteristics of intermittent and random power consumption, they will produce large power fluctuations when connected to the power grid on a large scale; at the same time, electric vehicles have energy storage characteristics and adjustable characteristics. Large-scale electric vehicles participating in power grid regulation can increase the peak-shaving capacity of the power grid. By optimizing the charging and discharging power of electric vehicles, load characteristics can be improved and the consumption of new energy can be promoted. Under reasonable and controlled charging and discharging regulation, the access of electric vehicles can effectively achieve peak shaving and valley filling, balance the load of the power grid, promote the consumption of new energy and optimize the configuration of energy storage.

[0007] Therefore, how to enable electric vehicles to participate in grid regulation has gradually become a problem that needs to be solved urgently. Summary of the invention

[0008] The technical problem to be solved by the present invention is to provide a method and terminal for electric vehicles to participate in grid regulation, so as to effectively realize peak shaving and valley filling of the grid, balance the load, promote the consumption of new energy and optimize the energy storage configuration.

[0009] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0010] A method for electric vehicles to participate in power grid regulation, comprising the steps of:

[0011] S1. Generate a future predicted charging power curve based on the actual operation data of the power grid;

[0012] S2. During a preset peak load period, according to the predicted charging power curve, adjusting the electric vehicles in the regional power grid to reversely provide electric energy to the power grid to obtain an adjusted charging power curve;

[0013] S3. absorbing the output of the new energy according to the adjusted charging power curve.

[0014] In order to solve the above technical problems, another technical solution adopted by the present invention is:

[0015] A terminal for electric vehicles to participate in grid regulation includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When executing the computer program, the processor implements the steps in the method for electric vehicles to participate in grid regulation as described above.

[0016] The beneficial effects of the present invention are as follows: the present invention provides a method and terminal for electric vehicles to participate in grid regulation, which predicts the charging power curve in the future based on the current charging power of the electric vehicle, and at the same time fully utilizes the energy storage characteristics and adjustable characteristics of the electric vehicle to participate in grid peak load regulation, and reversely provides electric energy to the grid during peak load periods, which can not only optimize the energy storage configuration of the grid, effectively realize peak shaving and valley filling and load balancing of the grid, but also promote the consumption of new energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is an overall flow chart of a method for electric vehicles to participate in power grid regulation according to an embodiment of the present invention;

[0018] Figure 2 It is a schematic diagram of the relationship between the load curve and the new energy output curve after the system load deducts the conventional power supply in an embodiment of the present invention;

[0019] Figure 3 Schematic diagram of the relationship between charging power curves before and after an electric vehicle adjusts the power grid in an embodiment of the present invention;

[0020] Figure 4 Schematic diagram of the relationship between the system load curve and the new energy output curve after the electric vehicle adjusts the power grid in an embodiment of the present invention;

[0021] Figure 5 It is a schematic diagram of the relationship between the regional tie line power curve, the new energy output curve, the energy storage system power curve and the system load curve when the electric vehicle does not participate in regulating the power grid in an embodiment of the present invention;

[0022] Figure 6It is a schematic diagram of the relationship between the regional tie line power curve, the new energy output curve, the energy storage system power curve and the system load curve under the electric vehicle participation in regulating the power grid in an embodiment of the present invention;

[0023] Figure 7 It is a structural schematic diagram of a terminal for electric vehicles to participate in grid regulation according to an embodiment of the present invention.

[0024] Description of labels:

[0025] 1. A terminal for electric vehicles to participate in grid regulation; 2. Memory; 3. Processor. DETAILED DESCRIPTION

[0026] In order to explain the technical content, achieved objectives and effects of the present invention in detail, the following is an explanation in combination with the implementation modes and the accompanying drawings.

[0027] Please refer to Figures 1 to 6 , a method for electric vehicles to participate in power grid regulation, comprising the steps of:

[0028] S1. Generate a future predicted charging power curve based on the actual operation data of the power grid;

[0029] S2. During a preset peak load period, according to the predicted charging power curve, adjusting the electric vehicles in the regional power grid to reversely provide electric energy to the power grid to obtain an adjusted charging power curve;

[0030] S3. absorbing the output of the new energy according to the adjusted charging power curve.

[0031] From the above description, it can be seen that the beneficial effects of the present invention are: based on the current charging power of the electric vehicle, the charging power curve in the future period is predicted, and at the same time, the energy storage characteristics and adjustable characteristics of the electric vehicle are fully utilized to participate in the peak load regulation of the power grid, and reversely provide electric energy to the power grid during peak load periods. This can not only optimize the energy storage configuration of the power grid, effectively realize peak shaving and valley filling and load balancing of the power grid, but also promote the consumption of new energy.

[0032] Furthermore, the step S1 specifically includes the following steps:

[0033] S11. Divide the regional power grid into multiple sub-regions according to the administrative division of the regional power grid, and predict the maximum charging power of electric vehicles in different sub-regions through actual power grid operation data to obtain an array P:

[0034] P=[P 1 ,P 2 …P i …P n ],i∈[1,n] (1);

[0035] Among them, Pi represents the predicted maximum charging power of the electric vehicle in the i-th sub-area, and n represents the number of the sub-areas;

[0036] S12, predicting the maximum charging power P of the electric vehicles in the regional power grid according to the actual operation data of the power grid max , and define the charging power simultaneous rate λ, and get formula (2):

[0037]

[0038] Among them, the value range of the simultaneity rate λ is 0.8~1.0;

[0039] S13, solving formula (2) to obtain the value P' of the maximum value of the predicted charging power of each sub-area after considering the simultaneous rate:

[0040] P'=[P 1 ',P 2 '…P i '…P n '],i∈[1,n] (3);

[0041] Among them, P i ' represents the predicted maximum charging power of the electric vehicle in the i-th sub-region in the regional power grid after considering the simultaneous rate;

[0042] S4, analyzing the corresponding relationship between P and P', predicting the charging power of electric vehicles in the regional power grid in the next 24 hours, and obtaining the predicted charging power curve P predict (t):

[0043]

[0044] Among them, P orig.max and P orig (t) are respectively the maximum charging power and charging power curve of electric vehicles in the regional power grid in the past 24 hours obtained based on the actual power grid operation data.

[0045] From the above description, it can be seen that due to the randomness of electric vehicle charging, based on the user's electricity consumption characteristics and the charging time of electric vehicles, for electric vehicles in the regional power grid, there is a certain proportional relationship between the charging power and the total charging power in the same period. The regional power grid is divided into multiple sub-regions according to administrative divisions. When the charging power of electric vehicles in the regional power grid reaches a maximum value at a certain moment, the charging power of electric vehicles in each sub-region at that moment is not necessarily the maximum value. Therefore, in order to accurately estimate the charging power of electric vehicles in each sub-region when the charging power of electric vehicles in the entire regional power grid is at its maximum value, the simultaneous rate λ is introduced to predict the maximum charging power of each sub-region, and then the corresponding relationship between the predicted value obtained without introducing the simultaneous rate λ and the predicted value obtained by introducing the simultaneous rate λ is used to predict the charging power curve of the entire regional power grid in the next 24 hours, thereby improving the rationality of subsequent electric vehicles participating in the peak load moment regulation of the power grid.

[0046] Furthermore, the step S2 is specifically as follows:

[0047] Before the peak load period, the charging power of the electric vehicles participating in the grid regulation is adjusted, and during the peak load period, according to the different charge states of different electric vehicles, the ratio of the charging power of the electric vehicles participating in the grid regulation in the regional grid to the initial charging power is defined as α, and the charging power curve P' is adjusted. predict (t):

[0048] P' predict (t) = P predict (t)-αP predict (t),t∈[1,24] (5);

[0049] Among them, P predict (t) is the predicted charging power curve, and the value range of α is 0.3 to 0.6;

[0050] The charging power curve needs to satisfy the following formula (6):

[0051]

[0052] Among them, t 1 and t 2 are the starting time and ending time of the period when the electric vehicle adjusts the charging power before the peak load period, t 3 and t 4 are the starting and ending time points of the peak load period respectively.

[0053] From the above description, it can be seen that considering the different charge states of different electric vehicles, electric vehicles at the same time should participate in the regulation of the peak load moment of the power grid according to their own charge states, so α is introduced to achieve the purpose of peak regulation; at the same time, according to the needs of electric vehicle users, it is necessary to ensure that the electric vehicle has sufficient power when the user uses the electric vehicle the next day. Therefore, when the electric vehicle participates in the regulation of the peak load period of the power grid, it is necessary to increase the charging power of the corresponding period before the regulation to charge the electric vehicle to ensure the regulation effect during the peak load period, that is, the amount of charge of the electric vehicle before participating in the regulation should be basically balanced with the amount of power reversely charged to the power grid during the peak load period.

[0054] Furthermore, the step S3 is specifically as follows:

[0055] During peak load periods:

[0056] If the electric vehicles in the regional power grid do not participate in the grid regulation, the remaining new energy output curve △P(t) after the new energy is consumed is obtained:

[0057] ΔP(t)=P RES (t)-P L1 (t)-P predict (t),t∈[1,24] (7);

[0058] Among them, P predict (t) is the predicted charging power curve, P L1 (t) is the load power curve after conventional power supply output, P RES (t) is the new energy output curve;

[0059] If the electric vehicles in the regional power grid participate in the grid regulation, the adjusted remaining new energy output curve △P'(t) and the adjusted charging power curve P' are obtained. predict (t) Relationship:

[0060] ΔP'(t)=P RES (t)-(P L1 (t)-P predict (t)+P' predict (t)) (8).

[0061] From the above description, it can be seen that the charging power curve of electric vehicles participating in grid regulation not only provides electric energy to the conventional power source of the regional power grid during peak load periods, but also promotes the consumption of new energy, thereby optimizing the energy storage configuration of the power grid while achieving peak load shaving and valley filling.

[0062] Furthermore, the step S3 further includes the following steps:

[0063] S4. When the electric vehicles in the regional power grid participate in the grid regulation, if the new energy consumption cannot be met, then based on the power balance constraint, the remaining new energy output is further consumed through the energy storage control of the energy storage system or the exchange of the regional interconnection line;

[0064] The power balance constraint is defined as:

[0065] P line (t)+P RES (t) = P B (t)+P L1 (t)-P predict (t)+P' predict (t) (9);

[0066] Among them, P line represents the real-time active power of the inter-regional tie line, which is a function of time t, and defines the real-time active power of the inter-regional tie line from the grid side to the load as the positive direction; P B It represents the active power absorbed by the energy storage system in real time, and is also a function of time t. It is defined that the direction in which the active power absorbed by the energy storage system in real time flows toward the energy storage system is the positive direction.

[0067] From the above description, it can be seen that when the regulation of electric vehicles cannot meet the consumption of new energy output in the regional power grid, the consumption of new energy can be further promoted by introducing energy storage control of the energy storage system or regional interconnection line exchange, thereby further optimizing the energy storage configuration of the power grid.

[0068] Furthermore, the energy storage control and consumption of the remaining new energy output by the energy storage system is specifically as follows:

[0069] Establish the objective function:

[0070] min F=C ESS (10);

[0071] Wherein, min F represents the minimum capacity of the energy storage system configured in the regional power grid, C ESS is the current energy storage capacity of the energy storage system;

[0072] The energy storage system satisfies the following energy storage charge state constraints:

[0073] SOC min ≤SOC(t)≤SOC max (11);

[0074] Among them, SOC min Indicates the lower limit of the energy storage system's state of charge, SOC max Indicates the upper limit of the state of charge of the energy storage system. SOC indicates the real-time state of charge of the energy storage system, which is a function of time t;

[0075] The energy storage system is controlled to operate in a daily cycle, and the following constraints must be met in each cycle:

[0076] SOC(0)=SOC(24)=SOC min (12);

[0077]

[0078] Furthermore, the energy storage control further includes:

[0079] The energy storage system meets the charging and discharging speed constraints:

[0080] W B ≤C ESS S max (14);

[0081] Among them, W B represents the charging and discharging power of the energy storage system, S max It indicates the maximum charge and discharge rate of the energy storage system, and its value ranges from 0.5C to 2C.

[0082] From the above description, it can be seen that the energy storage system participates in the consumption of new energy under the regulation of satisfying the energy storage charge state constraints and charging and discharging speed constraints, and further realizes the optimization of the grid energy storage configuration.

[0083] Furthermore, the exchange and consumption of the remaining new energy output through the regional interconnection line is specifically as follows:

[0084] Through the transmission and consumption of part of the new energy processing of the inter-regional tie line, the real-time transmission active power constraint of the inter-regional tie line is:

[0085] P line ≤P line.N (15);

[0086] Among them, P line.N It indicates the maximum power transmitted by the inter-regional interconnection line.

[0087] From the above description, it can be seen that the regional interconnection line is the interconnection line between the regional power grid and other regional power grids. That is, when there is a power imbalance in the current regional power grid, the power can be transmitted externally through the connection between the regional interconnection line and the power grid outside the region. At the same time, the power grid outside the region can also send power back to the current regional power grid, realizing mutual power support and further promoting the consumption of new energy.

[0088] Furthermore, step S3 also includes constraints on the amount of abandoned new energy:

[0089]

[0090] Among them, △P aband P represents the amount of abandoned renewable energy. ab (t) represents the amount of renewable energy that cannot be consumed at the corresponding time, △P aband.N Indicates the maximum amount of power abandonment allowed by the new energy system.

[0091] From the above description, it can be seen that when electric vehicles participate in the regulation of the power grid during peak load periods, the amount of abandoned power from new energy sources should also be considered, that is, the amount of abandoned power from new energy sources is not considered as part of the output of new energy sources absorbed by electric vehicles.

[0092] Please refer to Figure 7 A terminal for electric vehicles to participate in grid regulation includes a memory, a processor, and a computer program stored in the memory and executable on the processor. When executing the computer program, the processor implements the steps in the method for electric vehicles to participate in grid regulation as described above.

[0093] From the above description, it can be seen that the beneficial effects of the present invention are: based on the same technical concept, in conjunction with the above-mentioned method for electric vehicles to participate in grid regulation, a terminal for electric vehicles to participate in grid regulation is provided, based on the current charging power of the electric vehicle, the charging power curve in the future period is predicted, and at the same time, the energy storage characteristics and adjustable characteristics of the electric vehicle are fully utilized to participate in the peak load regulation of the grid, and reversely provide electric energy to the grid during peak load periods, which can not only optimize the energy storage configuration of the grid, effectively realize peak shaving and valley filling and load balancing of the grid, but also promote the consumption of new energy.

[0094] The present invention provides a method and terminal for electric vehicles to participate in grid regulation, which is applicable to the regional grid distribution dispatching scenario under the growth of new energy electric vehicles, and realizes peak load shaving and valley filling of the grid, load balancing, promotion of new energy consumption and optimization of energy storage configuration. The following is a detailed description in conjunction with the embodiments.

[0095] Please refer to Figure 1 , Embodiment 1 of the present invention is:

[0096] A method for electric vehicles to participate in grid regulation, such as Figure 1 As shown, the steps include:

[0097] S1. Generate the future predicted charging power curve based on the actual operation data of the power grid.

[0098] S2. According to the predicted charging power curve during the preset peak load period, the electric vehicles in the regional power grid are regulated to reversely supply electric energy to the power grid to obtain an regulated charging power curve;

[0099] The peak load period may be manually set and may be adjusted according to actual needs. In other equivalent embodiments, it may also be obtained based on actual grid operation data.

[0100] S3. Absorb the output of new energy sources according to the adjusted charging power curve.

[0101] That is, in this embodiment, based on the current charging power of the electric vehicle, the charging power curve in the future is predicted, and at the same time, the energy storage characteristics and adjustable characteristics of the electric vehicle are fully utilized to participate in the peak load regulation of the power grid, and reversely provide electric energy to the power grid during peak load periods. This can not only optimize the energy storage configuration of the power grid, effectively achieve peak shaving and valley filling and load balancing of the power grid, but also promote the consumption of new energy.

[0102] Embodiment 2 of the present invention is:

[0103] A method for electric vehicles to participate in power grid regulation, based on the above-mentioned embodiment 1, in this embodiment, since the charging of electric vehicles is random, based on the power consumption characteristics of users and the charging time of electric vehicles, for electric vehicles in a regional power grid, the charging power in the same period has a certain proportional relationship with the total charging power. On this basis, step S1 specifically includes the following steps:

[0104] S11. Divide the regional power grid into multiple sub-regions according to the administrative division of the regional power grid, and predict the maximum charging power of electric vehicles in different sub-regions through actual power grid operation data to obtain an array P:

[0105] P=[P 1 ,P 2 …P i …P n ],i∈[1,n] (1);

[0106] Among them, P i represents the predicted maximum charging power of the electric vehicle in the i-th sub-area, and n represents the number of sub-areas.

[0107] When the charging power of electric vehicles in the regional power grid reaches the maximum value at a certain moment, the charging power of electric vehicles in each sub-region may not be the maximum value at that moment. Therefore, in order to accurately estimate the charging power of electric vehicles in each sub-region when the charging power of electric vehicles in the entire regional power grid reaches the maximum value, the simultaneous rate λ is introduced to predict the maximum charging power of each sub-region, that is, the following steps:

[0108] S12, predict the maximum charging power P of electric vehicles in the regional power grid based on the actual operation data of the power grid max , and define the charging power simultaneous rate λ, and get formula (2):

[0109]

[0110] In this embodiment, the value range of the simultaneity rate λ is 0.8 to 1.0.

[0111] S13. Solve formula (2) to obtain the value P' of the maximum predicted charging power of each sub-area after considering the simultaneous rate:

[0112] P'=[P 1 ',P 2 '…P i '…P n '],i∈[1,n] (3);

[0113] Among them, P i ' represents the maximum predicted charging power of electric vehicles in the ith sub-region of the regional power grid after considering the simultaneous rate;

[0114] S4. Analyze the corresponding relationship between P and P', predict the charging power of electric vehicles in the regional power grid in the next 24 hours, and obtain the predicted charging power curve P predict (t):

[0115]

[0116] Among them, P orig.max and P orig (t) are the maximum charging power and charging power curve of electric vehicles in the regional power grid in the past 24 hours obtained based on the actual power grid operation data.

[0117] That is, the corresponding relationship between the predicted value without introducing the simultaneous rate λ and the predicted value with introducing the simultaneous rate λ is used to predict the charging power curve of the entire regional power grid in the next 24 hours, thereby improving the rationality of subsequent electric vehicles participating in the regulation of the peak load moment of the power grid.

[0118] At the same time, in this embodiment, since the power grid has difficulty in peak load regulation during peak load periods, and a large number of residential electric vehicles are in a charging state at this time, if the charging electric vehicles are reversely supplied with electric energy to the regional power grid at this time to alleviate the load output of the regional power grid, that is, step S2 is specifically as follows:

[0119] Before the peak load period, the charging power of electric vehicles participating in grid regulation is adjusted. During the peak load period, according to the different charge states of different electric vehicles, the ratio of the charging power of electric vehicles participating in grid regulation in the regional grid to the initial charging power is defined as α, and the charging power curve P' is adjusted. predict (t):

[0120] P' predict (t) = P predict(t)-αP predict (t),t∈[1,24] (5);

[0121] In this embodiment, the value range of α is 0.3 to 0.6.

[0122] That is, adjust the charging power curve P' predict (t) During peak load periods, the charging power will be less than the predicted charging power curve P under the adjustment of α. predict (t) is equivalent to reducing the charging power that should have been achieved during the peak load period in order to provide electric energy to the grid in reverse as compensation. It can be understood as a reduction in charging power, or it can be understood as the electric vehicle outputting power to the grid as energy storage at this time to achieve the purpose of peak load regulation.

[0123] On the other hand, according to the needs of electric vehicle users, it is necessary to ensure that the electric vehicle has sufficient power when the user uses the electric vehicle the next day. Therefore, when the electric vehicle participates in the peak load period regulation of the power grid, it is necessary to increase the charging power of the corresponding period before the regulation to charge the electric vehicle to ensure the regulation effect during the peak load period. That is, the amount of charge of the electric vehicle before participating in the regulation should be basically balanced with the amount of reverse charging to the power grid during the peak load period. The adjustment charging power curve needs to satisfy the following formula (6):

[0124]

[0125] Among them, t 1 and t 2 are the starting time and ending time of the period when the electric vehicle adjusts the charging power before the peak load period, t 3 and t 4 are the starting and ending time points of the peak load period respectively.

[0126] At the same time, in this embodiment, step S3 also specifically includes the following steps:

[0127] During peak load periods:

[0128] If the electric vehicles in the regional power grid do not participate in the grid regulation, the remaining new energy output curve △P(t) after the new energy consumption is obtained:

[0129] ΔP(t)=P RES (t)-P L1 (t)-P predict (t),t∈[1,24] (7);

[0130] Among them, P L1 (t) is the load power curve after conventional power supply output, P RES (t) is the new energy output curve.

[0131] If the electric vehicles in the regional power grid participate in the grid regulation, the adjusted remaining new energy output curve △P'(t) and the adjusted charging power curve P' are obtained. predict (t) Relationship:

[0132] ΔP'(t)=P RES (t)-(P L1 (t)-P predict (t)+P' predict (t)) (8).

[0133] It can be seen from formula (8) that at the peak load moment of the power grid, when electric vehicles participate in the power grid regulation, it is necessary to first subtract the electric vehicle load when the electric vehicles did not participate in the power grid regulation from the original conventional power output load. The load after subtraction does not include the electric vehicle load, and then it is necessary to add the electric vehicle load after the regulation to obtain the new load characteristic curve of the regional power grid, and finally subtract it from the new energy output, so as to finally obtain the residual value after the new energy is absorbed. Combined with formula (7), it is not difficult to know that △P'(t) after regulation will be smaller than △P(t) before regulation, and it can be obtained that the new energy absorption after regulation is better than the new energy absorption before regulation. That is, the charging power curve of electric vehicles participating in the power grid regulation not only provides electric energy for the conventional power supply of the regional power grid in the peak load period, but also promotes the absorption of new energy, and optimizes the energy storage configuration of the power grid while realizing the peak load reduction and valley filling of the power grid.

[0134] Meanwhile, in this embodiment, step S3 further includes the following steps:

[0135] S4. When electric vehicles in the regional power grid participate in grid regulation, if they cannot meet the needs of new energy consumption, the remaining new energy output will be further consumed through energy storage control of the energy storage system or exchange of regional interconnection lines based on power balance constraints;

[0136] The power balance constraint is defined as:

[0137] P line (t)+P RES (t) = P B (t)+P L1 (t)-P predict (t)+P' predict (t) (9);

[0138] Among them, P line It represents the real-time active power of the inter-regional tie line, which is a function of time t. The real-time active power of the inter-regional tie line is defined as the positive direction from the grid side to the load side. BIt represents the active power absorbed by the energy storage system in real time, which is also a function of time t. The direction in which the active power absorbed by the energy storage system in real time flows toward the energy storage system is defined as the positive direction.

[0139] That is, in this embodiment, when the regulation of electric vehicles cannot meet the consumption of new energy output in the regional power grid, the consumption of new energy can be further promoted by introducing energy storage control of the energy storage system or regional interconnection line exchange, thereby further optimizing the energy storage configuration of the power grid.

[0140] Specifically, in this embodiment, the remaining new energy output is absorbed by the energy storage control of the energy storage system, specifically:

[0141] Establish the objective function:

[0142] min F=C ESS (10);

[0143] Where min F represents the minimum capacity of the energy storage system in the regional power grid, C ESS is the current energy storage capacity of the energy storage system.

[0144] The energy storage system needs to meet the following energy storage charge state constraints:

[0145] SOC min ≤SOC(t)≤SOC max (11);

[0146] Among them, SOC min Indicates the lower limit of the energy storage system's state of charge, SOC max It represents the upper limit of the state of charge of the energy storage system. SOC represents the real-time state of charge of the energy storage system, which is a function of time t.

[0147] At the same time, the energy storage system is controlled to operate in a daily cycle, and the following constraints must be met in each cycle:

[0148] SOC(0)=SOC(24)=SOC min (12);

[0149]

[0150] Among them, energy storage control also includes:

[0151] The energy storage system needs to meet the charging and discharging speed constraints:

[0152] W B ≤C ESS S max (14);

[0153] Among them, W B Represents the charging and discharging power of the energy storage system, Smax Indicates the maximum charge and discharge rate of the energy storage system. In this embodiment, its value is 0.5C~2C.

[0154] That is, the energy storage system participates in the consumption of new energy under the regulation of satisfying the energy storage charge state constraints and charging and discharging speed constraints, which can further optimize the energy storage configuration of the power grid.

[0155] In this embodiment, the remaining new energy output is absorbed through the exchange of regional interconnection lines, specifically:

[0156] Through the transmission and consumption of part of the new energy through the inter-regional interconnection line, the real-time transmission active power constraint of the inter-regional interconnection line is:

[0157] P line ≤P line.N (15);

[0158] Among them, P line.N Indicates the maximum outgoing power of the inter-regional interconnection line.

[0159] The regional interconnection line is the interconnection line between the regional power grid and other regional power grids. That is, when there is a power imbalance in the current regional power grid, the power can be transmitted through the connection with the power grid outside the region through the regional interconnection line. At the same time, the power grid outside the region can also send power back to the current regional power grid, realizing mutual power support and further promoting the consumption of new energy.

[0160] In addition, in this embodiment, when electric vehicles participate in the regulation of the peak load period of the power grid, the amount of abandoned power of new energy should also be considered, that is, the amount of abandoned power of new energy is not considered as part of the output of new energy consumed by electric vehicles. Therefore, step S3 should also include a constraint on the amount of abandoned power of new energy:

[0161]

[0162] Among them, △P aband P represents the amount of abandoned renewable energy. ab (t) represents the amount of renewable energy that cannot be consumed at the corresponding time, △P aband.N Indicates the maximum amount of power abandonment allowed by the new energy system.

[0163] Please refer to Figures 2 to 6 , Embodiment 3 of the present invention is:

[0164] A method for electric vehicles to participate in grid regulation. Based on the above second embodiment, in this embodiment, the method for electric vehicles to participate in grid regulation in the second embodiment is applied to an actual grid in a certain area.

[0165] It is known that the installed capacity of renewable energy in the regional power grid is 800MW, of which wind power is 500MW and photovoltaic power is 300MW. The load power curve and renewable energy output curve of the regional power grid after deducting the conventional power supply are as follows: Figure 2 shown.

[0166] The regional power grid contains a large number of electric vehicles. According to the load (charging power) curve of the electric vehicles and a method for electric vehicles to participate in power grid regulation in this embodiment, the proportion α of the initial charging power participating in the peak load regulation of the power grid is taken as 0.5, and the regulated charging power curve of the regional power grid is obtained. The predicted charging power curve and the regulated charging power curve of the electric vehicles are as follows: Figure 3 shown.

[0167] according to Figure 3 The results shown in the figure show that the charging power curve and new energy output curve of the electric vehicle before and after adjustment are as follows: Figure 4 As shown, from Figure 4 It can be seen that when electric vehicles are used to participate in grid regulation, the peak load at peak load times is effectively reduced. At the same time, the charging power of electric vehicles is increased at noon, which also effectively promotes the consumption of new energy at noon.

[0168] However, there are still problems with the consumption of new energy at this time, and it is necessary to further consider the participation of energy storage systems and regional interconnection lines in the consumption of new energy. Figure 2 or Figure 4 The new energy output curve roughly estimates that the new energy power generation of the regional power grid is 8998.2MWh. Considering the 5% new energy power abandonment rate, the new energy power abandonment of the regional power grid is 449.91MWh.

[0169] When electric vehicles do not participate in grid regulation, when the power abandonment rate of the regional grid is constrained to 5% and the regional interconnection line transmission power constraint is that the power change does not exceed 45MW, the capacity of the energy storage system is configured to be 110MWh. The relationship between the regional interconnection line power curve, the new energy output curve, the energy storage power curve of the energy storage system and the system load power curve of the regional grid is as follows: Figure 5 As shown. Figure 5 When the power of the central area interconnection line is negative, it indicates that it is the external transmission power. Since the change in external transmission power is constrained to 45MW, the remaining power is the abandoned power of the regional power grid.

[0170] When electric vehicles participate in grid regulation, the minimum capacity of the energy storage system configured to meet the constraint of renewable energy curtailment is calculated according to step S3 in the second embodiment to be 50MWh. At this time, the relationship between the regional interconnection line curve, renewable energy output curve, energy storage power curve of the energy storage system and system load power curve of the regional power grid is as follows: Figure 6 shown.

[0171] Depend on Figure 5 and Figure 6 From the comparison, it can be seen that when electric vehicles are considered to participate in grid regulation, the following beneficial effects are achieved: ① It can effectively smooth the load during the peak load period of the grid; ② It can effectively promote the consumption of new energy at noon. With the development of photovoltaic power generation, the consumption of new energy at noon will become a key issue; ③ The participation of electric vehicles in grid regulation can effectively reduce the energy storage configuration capacity of the energy storage system. From the perspective of flexible and adjustable resources, the essence of electric vehicles participating in grid regulation is not only to reduce the load on the grid, but also to serve as a mode of energy storage, releasing power when regulation is required.

[0172] Please refer to Figure 6 , Embodiment 4 of the present invention is:

[0173] A terminal 1 for an electric vehicle to participate in grid regulation includes a memory 2, a processor 3, and a computer program stored in the memory 2 and executable on the processor 3. In this embodiment, the processor 3 implements the steps of any one of the above-mentioned embodiments 1 to 3 when executing the computer program.

[0174] In summary, the present invention provides a method and terminal for electric vehicles to participate in grid regulation, which utilizes electric vehicle loads to participate in grid peak load regulation, and considers constraints such as electric vehicle load (charging power) simultaneity rate, energy storage system energy storage charge state constraints and charging and discharging speed constraints, regional grid interconnection line power constraints, new energy abandonment power constraints, and electric vehicle power imbalance. A method for electric vehicles to participate in grid regulation is proposed, which can make full use of the energy storage characteristics and adjustable characteristics of electric vehicles, can not only optimize the energy storage configuration of the grid, effectively realize peak shaving and valley filling and load balancing of the grid, but also promote the consumption of new energy, which is beneficial to improving the safety and stability level of the grid, and has important engineering practice significance.

[0175] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent transformations made using the contents of the present invention's specification and drawings, or directly or indirectly applied in related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A method for electric vehicles to participate in power grid regulation, It is characterized in that Includes steps: S1. Generate a future predicted charging power curve based on the actual operation data of the power grid; S2. According to the predicted charging power curve during the preset peak load period, the electric vehicles in the regional power grid are regulated to reversely supply electric energy to the power grid to obtain an regulated charging power curve; S3, absorbing the output of new energy according to the adjustment of charging power curve; Step S1 specifically includes the following steps: S11. Divide the regional power grid into multiple sub-regions according to the administrative division of the regional power grid, and predict the maximum charging power of electric vehicles in different sub-regions through actual power grid operation data to obtain an array P : （1）； in, P i Indicates i The predicted maximum charging power of electric vehicles in each sub-area, n Indicates the number of sub-regions; S12, predict the maximum charging power of electric vehicles in the regional power grid based on the actual operation data of the power grid P max , and define the charging power rate at the same time λ , we get formula (2): (2)； Among them, the value range of the simultaneity rate λ is 0.8~1.0; S13. Solve formula (2) to obtain the value of the maximum predicted charging power of each sub-area after considering the simultaneous rate. P’ : （3）； in, P i ’ It means that after considering the simultaneity rate, the calculated i The predicted maximum charging power of electric vehicles in each sub-area; S14. Analysis P and P’ The corresponding relationship is used to predict the charging power of electric vehicles in the regional power grid in the next 24 hours, and the predicted charging power curve is obtained. P predict (t) : (4)； in, P orig.max and P orig (t) They are the maximum charging power and charging power curve of electric vehicles in the regional power grid in the past 24 hours obtained based on the actual power grid operation data; Step S2 is specifically as follows: Before the peak load period, the charging power of electric vehicles participating in grid regulation is adjusted, and during the peak load period, according to the different charge states of different electric vehicles, the ratio of the charging power of electric vehicles participating in grid regulation in the regional power grid to the initial charging power is defined as α , then adjust the charging power curve P’ predict (t) : （5）； in, P predict (t) To predict the charging power curve, α The value range of is 0.3~0.6; The following formula (6) needs to be satisfied to adjust the charging power curve: （6）； in, t 1 and t 2 are the starting time point and the ending time point corresponding to the period when the electric vehicle adjusts the charging power before the peak load period, t 3 and t 4 are the starting time point and the ending time point of the peak load period respectively; Step S3 is specifically as follows: During peak load periods: If the electric vehicles in the regional power grid do not participate in the grid regulation, the remaining new energy output curve after the new energy consumption is obtained △P(t) : （7）； in, P predict (t) To predict the charging power curve, P L1 (t) It is the load power curve after the conventional power supply output. P RES (t) Output curve for new energy; If electric vehicles in the regional power grid participate in grid regulation, the adjusted remaining renewable energy output curve is obtained. △P’ (t) And adjust the charging power curve P’ predict (t) Relationship: （8）。 2. A method for electric vehicles to participate in grid regulation according to claim 1, It is characterized in that The step S3 further includes the following steps: S4. When the electric vehicles in the regional power grid participate in the grid regulation, if the new energy consumption cannot be met, then based on the power balance constraint, the remaining new energy output is further consumed through the energy storage control of the energy storage system or the exchange of the inter-regional interconnection lines; The power balance constraint is defined as: （9）； in, P line represents the real-time active power of the inter-regional tie line, which is the time t The function defines the direction of the real-time active power of the inter-regional tie line from the grid side to the load as the positive direction; P B Indicates the active power absorbed by the energy storage system in real time, also known as time t The function defines the direction in which the active power absorbed by the energy storage system in real time flows toward the energy storage system as the positive direction.

3. A method for electric vehicles to participate in grid regulation according to claim 2, It is characterized in that The energy storage control and consumption of the remaining new energy output by the energy storage system is specifically as follows: Establish the objective function: （10）； Among them, min F represents the minimum capacity of the energy storage system configured in the regional power grid, C ESS is the current energy storage capacity of the energy storage system; The energy storage system satisfies the following energy storage charge state constraints: （11）； in, SOC min Indicates the lower limit of the energy storage system's state of charge, SOC max Indicates the upper limit of the energy storage system's state of charge. SOC Indicates the real-time charge state of the energy storage system, which is time t Function of The energy storage system is controlled to operate in a daily cycle, and the following constraints must be met in each cycle: （12）； （13）。 4. A method for electric vehicles to participate in grid regulation according to claim 3, It is characterized in that The energy storage control further includes: The energy storage system meets the charging and discharging speed constraints: （14）； in, W B Indicates the charging and discharging power of the energy storage system ，S max It represents the maximum charge and discharge rate of the energy storage system, and its value ranges from 0.5C to 2C.

5. A method for electric vehicles to participate in grid regulation according to claim 2, It is characterized in that The remaining renewable energy output is absorbed through the exchange of inter-regional interconnection lines, specifically: Through the transmission and consumption of part of the new energy processing of the inter-regional tie line, the real-time transmission active power constraint of the inter-regional tie line is: （15）； in, P line.N It indicates the maximum power transmitted by the inter-regional interconnection line.

6. A method for electric vehicles to participate in grid regulation according to claim 1, It is characterized in that The step S3 also includes constraints on the amount of abandoned new energy: （16）； in, △P aband Indicates the amount of abandoned electricity from new energy sources. P ab (t) Indicates the amount of new energy electricity that cannot be consumed at the corresponding time. △ P aband.N Indicates the maximum amount of power abandonment allowed by the new energy system.

7. A terminal for electric vehicles to participate in grid regulation, It is characterized in that The invention comprises a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps in a method for electric vehicles to participate in grid regulation as described in any one of claims 1 to 6 when executing the computer program.

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