Disclosure of Invention
In view of this, the application provides a power distribution network double-layer planning method, device, equipment and storage medium, when planning a power distribution network, uncertainty of an electric vehicle is considered, the power distribution network is accurately planned, and the technical problem that the power distribution network cannot be planned based on electric vehicle loads in the existing power distribution network planning method is solved.
The application provides in a first aspect a power distribution network double-layer planning method, including:
acquiring a first load curve and electric vehicle information corresponding to a power distribution network to be planned;
simulating a charging load curve corresponding to each electric automobile according to the electric automobile information;
superposing the first load curve and the charging load curve to obtain a second load curve;
constructing a double-layer optimization model for planning the power distribution network according to an opportunity constraint method based on the second load curve;
and solving the double-layer optimization model to obtain a planning result of the power distribution network to be planned.
Optionally, according to the electric vehicle information, a charging load curve corresponding to each electric vehicle is simulated, and the method specifically includes:
acquiring a charging demand model corresponding to the electric automobile according to the electric automobile information;
calculating the corresponding charging required time according to the daily driving mileage corresponding to the electric automobile and the charging demand model;
and determining a charging load curve corresponding to the electric automobile according to the initial charging time, the charging power and the required charging time corresponding to the electric automobile.
Optionally, according to the electric vehicle information, a charging demand model corresponding to the electric vehicle is acquired, and the method specifically includes:
acquiring automobile types corresponding to the electric automobiles from the automobile information;
and acquiring a charging demand model corresponding to the automobile type based on the corresponding relation between the automobile type and the charging demand model according to the automobile type.
Optionally, the car types include: electric buses, electric taxis and electric private cars.
Optionally, an objective function of an upper-layer optimization planning model in the two-layer optimization model is:
in the formula, CTTo make a distribution transformation full lifecycle cost, CIFor initial investment costs of distribution transformers, CWFor distribution transformation operating loss cost, COFor distribution transformer maintenance cost, CFFor distribution transformation fault costs, CDFor distribution transformation decommissioning disposal costs, XTFor alternative distribution network transformer types, STNThe capacity of the transformer of the alternative distribution network.
Optionally, an objective function of a lower-layer optimized planning model in the two-layer optimized model is:
in the formula, f is the average active power equivalently injected at the low-voltage side of the distribution network transformer,
and equivalently injecting active power to the low-voltage side of the distribution network transformer in the ith time period of the ith year.
This application second aspect provides a distribution network double-deck planning device, includes:
the acquiring unit is used for acquiring a first load curve and electric vehicle information corresponding to the power distribution network to be planned;
the simulation unit is used for simulating a charging load curve corresponding to each electric automobile according to the electric automobile information;
the overlapping unit is used for overlapping the first load curve and the charging load curve to obtain a second load curve;
the construction unit is used for constructing a double-layer optimization model for planning the power distribution network according to an opportunity constraint method based on the second load curve;
and the solving unit is used for solving the double-layer optimization model to obtain a planning result of the power distribution network to be planned.
Optionally, the simulation unit specifically includes:
the obtaining subunit is used for obtaining a charging demand model corresponding to the electric automobile according to the electric automobile information;
the calculating subunit is used for calculating the corresponding required charging time according to the daily driving mileage corresponding to the electric automobile and the charging demand model;
and the determining subunit is used for determining a charging load curve corresponding to the electric automobile according to the initial charging time, the charging power and the required charging time corresponding to the electric automobile.
The third aspect of the application provides a power distribution network double-layer planning device, which comprises a processor and a memory;
the memory is used for storing program codes and transmitting the program codes to the processor;
the processor is configured to execute the power distribution network double-layer planning method according to the first aspect according to instructions in the program code.
A fourth aspect of the present application provides a storage medium, where the storage medium is used to store program codes, and the program codes are used to execute the power distribution network double-layer planning method according to the first aspect.
According to the technical scheme, the method has the following advantages:
the application provides a power distribution network double-layer planning method which includes the steps of firstly obtaining a first load curve and electric vehicle information corresponding to a power distribution network to be planned, then simulating a charging load curve corresponding to each electric vehicle according to the electric vehicle information, then superposing the first load curve and the charging load curve to obtain a second load curve, then building a double-layer optimization model for planning the power distribution network according to an opportunity constraint method based on the second load curve, and finally solving the double-layer optimization model to obtain a planning result of the power distribution network to be planned. When the power distribution network is planned, uncertainty of the electric automobile is considered when the power distribution network is planned, and the power distribution network is planned by combining electric automobile information of the electric automobile, so that the technical problem that the power distribution network cannot be planned based on electric automobile loads in the conventional power distribution network planning method is solved.
Detailed Description
The embodiment of the application provides a power distribution network double-layer planning method, a power distribution network double-layer planning device, power distribution network double-layer planning equipment and a storage medium, wherein when the power distribution network is planned, uncertainty of an electric automobile is considered, the power distribution network is accurately planned, and the technical problem that the power distribution network cannot be planned based on electric automobile loads in the conventional power distribution network planning method is solved.
In order to make the technical solutions of the present application better understood, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.
The first aspect of the embodiment of the application provides an embodiment of a power distribution network double-layer planning method.
Referring to fig. 1, a schematic flow chart of a first embodiment of a power distribution network double-layer planning method in an embodiment of the present application includes:
step 101, obtaining a first load curve and electric vehicle information corresponding to a power distribution network to be planned.
It is understood that the first load curve is a conventional load curve in which the power distribution network to be planned does not include electric vehicle loads.
And 102, simulating a charging load curve corresponding to each electric automobile according to the electric automobile information.
After the electric vehicle information corresponding to the power distribution network to be planned is obtained, a charging load curve corresponding to the electric vehicle can be simulated based on the electric vehicle information. The charging load curve of the electric automobile in the region is reflected more truly in a load simulation mode.
And 103, overlapping the first load curve and the charging load curve to obtain a second load curve.
Because the charging load curve is obtained based on a simulation mode, the second load curve of the corresponding area of the power distribution network to be analyzed, which is obtained based on the charging load curve and the first load curve, is more real and closer to reality.
And 104, constructing a double-layer optimization model for planning the power distribution network according to an opportunity constraint method based on the second load curve.
It can be understood that after the second load curve corresponding to the power distribution network to be analyzed is obtained, a double-layer optimization model for power distribution network planning can be constructed according to an opportunity constraint method based on the second load curve. Because the charging load curve of the electric automobile is superposed in the second load curve, the electric automobile is also considered in the double-layer optimization model constructed according to the second load curve, and the uncertainty of the load of the electric automobile accessing the power distribution network is considered. Meanwhile, a double-layer optimization model for power distribution network planning is constructed based on an opportunity constraint method, and a more reasonable optimization scheme can be provided for power distribution network planning.
And 105, solving the double-layer optimization model to obtain a planning result of the power distribution network to be planned.
After a double-layer optimization model for planning the power distribution network is obtained, a planning result corresponding to the power distribution network to be planned can be obtained by solving the model.
In the embodiment, a first load curve and electric vehicle information corresponding to a power distribution network to be planned are obtained, a charging load curve corresponding to each electric vehicle is simulated according to the electric vehicle information, the first load curve and the charging load curve are superposed to obtain a second load curve, a double-layer optimization model for planning the power distribution network is constructed according to an opportunity constraint method based on the second load curve, and finally the double-layer optimization model is solved to obtain a planning result of the power distribution network to be planned. When the power distribution network is planned, uncertainty of the electric automobile is considered when the power distribution network is planned, and the power distribution network is planned by combining electric automobile information of the electric automobile, so that the technical problem that the power distribution network cannot be planned based on electric automobile loads in the conventional power distribution network planning method is solved.
The foregoing is a first embodiment of a power distribution network double-layer planning method provided in this application, and the following is a second embodiment of the power distribution network double-layer planning method provided in this application.
Referring to fig. 2, a schematic flow chart of a second embodiment of a power distribution network double-layer planning method in the embodiment of the present application includes:
step 201, obtaining a first load curve and electric vehicle information corresponding to a power distribution network to be planned.
It is understood that, in one embodiment, the electric vehicle information includes: the types of the electric vehicles and the number of the vehicles corresponding to each type of the electric vehicles are as follows, and specific electric vehicle information is as shown in the following table 1:
TABLE 1
| Type of electric vehicle
|
Number of cars
|
| Electric bus
|
80
|
| Electric taxi
|
200
|
| Electric private car
|
450 |
It should be noted that, while the first load curve and the electric vehicle information are acquired, distribution transformer information corresponding to the distribution network to be planned also needs to be acquired. The capacity models of the distribution transformer are shown in the following table 2:
TABLE 2
| Distribution network transformer model
|
Rated capacity/kVA of transformer of power distribution network
|
| S13
|
30,50,100,200,315,400,500,630
|
| SCB10
|
80,100,125,160,200,250,315,400,500,630,800,1000 |
It can be understood that, because the model is subsequently constructed and solved, other parameters need to be obtained, and specifically, the other parameters are as shown in table 3 below:
TABLE 3
Step 202, acquiring a charging demand model corresponding to the electric automobile according to the electric automobile information.
It can be understood that, in an embodiment, obtaining, according to the information of the electric vehicle, a charging demand model corresponding to the electric vehicle specifically includes:
acquiring automobile types corresponding to the electric automobiles from the automobile information;
and acquiring a charging demand model corresponding to the automobile type based on the corresponding relation between the automobile type and the charging demand model according to the automobile type.
Further, the above-mentioned automobile types include: electric buses, electric taxis and electric private cars.
And 203, calculating the corresponding charging required time according to the daily driving mileage corresponding to the electric automobile and the charging demand model.
It can be understood that the daily mileage of the electric vehicles of different vehicle types is different, and specifically, the mathematical model of the daily mileage distribution corresponding to the electric bus is as follows:
wherein s is the daily mileage of the electric bus, mus1And σs1Respectively is the average value and the standard deviation of the daily driving mileage of the electric bus.
The mathematical model of daily driving mileage distribution corresponding to the electric taxi is as follows:
in the formula, mus2And σs2Respectively is the average value and the standard deviation of the daily driving mileage of the electric taxi.
The mathematical model of daily mileage distribution corresponding to the electric private car is as follows:
in the formula, mus3And σs3Respectively representing the logarithmic mean value and the logarithmic standard deviation of the daily driving mileage of the electric private car, and Ins is the logarithmic value of the daily driving mileage of the electric private car.
And 204, determining a charging load curve corresponding to the electric automobile according to the initial charging time, the charging power and the required charging time corresponding to the electric automobile.
And obtaining the charging end time of the electric automobile according to the initial charging time and the required charging time of the electric automobile, and obtaining a charging load curve in the charging process according to the charging power (the charging load is the charging power in the time period of starting charging and ending charging).
It is understood that the starting charging time of the electric vehicles of different vehicle types is different, and specifically, the probability model of the starting charging time of the electric bus is shown in the following table 4:
TABLE 4
The probability model of the initial charging time corresponding to the electric taxi is shown in the following table 5:
TABLE 5
The probability model of the initial charging time corresponding to the electric private car is shown in the following table 6:
TABLE 6
In the formula, a
nIs a mixing ratio coefficient, satisfies
μ
nMathematical expectation for daily mileage of electric private car, sigma
nThe standard deviation of the daily driving mileage of the electric private car is shown.
It is understood that the steps 202 to 204 can be realized by a monte carlo simulation method, and the specific steps are as follows:
1) inputting system data, comprising: the charging power, the standard power consumption, the initial charging time and the probability model and the retention amount of the daily driving mileage of the electric automobile of each automobile type.
2) The number of times of initialization simulation M is 10000. Meanwhile, let m be 1, m is the number of times of simulation;
3) and initializing an electric vehicle holding quantity predicted value N. Meanwhile, let n be 1, n is the nth electric automobile to be sampled and simulated;
4) judging the automobile type of the nth electric automobile, and extracting the initial charging time and the daily driving mileage of the type of electric automobile by utilizing a Monte Carlo simulation method according to the charging demand models of the electric automobiles with different automobile types; combining the daily driving mileage obtained by random sampling with a charging demand model of the electric automobile, and calculating the time length required by charging according to the electric automobile; and obtaining a charging load curve of the electric automobile of the automobile through the sampled initial charging time, charging power and charging required time.
It can be understood that the charging load curve is calculated according to the daily driving mileage of the electric vehicle, that is, a daily charging load curve, in this embodiment, a daily charging load curve corresponding to the electric bus is shown in fig. 3, a daily charging load curve corresponding to the electric taxi is shown in fig. 4, and a daily charging load curve corresponding to the electric private car is shown in fig. 5.
And step 205, superposing the first load curve and the charging load curve to obtain a second load curve.
And during specific superposition, superposing (directly adding) the first load active curve and the charging load active curve at the same moment in the area to obtain a second load curve.
And step 206, constructing a double-layer optimization model for planning the power distribution network according to an opportunity constraint method based on the second load curve.
It should be noted that the decision variables of the upper-layer optimization planning model in the double-layer optimization model are the distribution network transformer model XT and the distribution network transformer rated capacity STN, the objective function is the minimum distribution network transformer LCC (full life cycle cost), and the objective function is:
in the formula, CTTo make a distribution transformation full lifecycle cost, CIFor initial investment costs of distribution transformers, CWFor distribution transformation operating loss cost, COFor distribution transformer maintenance cost, CFFor distribution transformation fault costs, CDFor distribution transformation decommissioning disposal costs, XTFor alternative distribution network transformer types, STNThe capacity of the transformer of the alternative distribution network.
The constraint conditions corresponding to the upper-layer optimization planning model comprise configuration constraints of the model number and the capacity of the power distribution network transformer:
in the formula, A is a model set of alternative distribution network transformers; and B is a capacity set of the alternative distribution network transformer.
The objective function of a lower-layer optimization planning model in the double-layer optimization model is that the active variance of equivalent load injection on the low-voltage side of the power distribution network transformer is minimum in the ith year, and the corresponding specific form is as follows:
in the formula, f is the average active power equivalently injected at the low-voltage side of the distribution network transformer,
and equivalently injecting active power to the low-voltage side of the distribution network transformer in the ith time period of the ith year.
The constraint conditions corresponding to the lower-layer optimization planning model are as follows:
(1) power distribution network transformer low-voltage side voltage opportunity constraint
Considering the influence of load and electric automobile access uncertainty, in order to avoid the voltage of the low-voltage side of the distribution network transformer from having a large voltage out-of-limit risk, the lower-layer optimized operation model sets the voltage opportunity constraint of the low-voltage side of the distribution network transformer, and the method specifically comprises the following steps:
in the formula (I), the compound is shown in the specification,
the voltage value of the low-voltage side of the distribution network transformer is the ith time period of the ith year; v
T2.max、V
T2.minThe upper limit value and the lower limit value of the voltage at the low-voltage side of the transformer of the power distribution network are respectively set; beta is a
VAnd for the confidence coefficient of the voltage at the low-voltage side of the distribution network transformer, Pr {. cndot.) represents the probability of the event establishment. According to the national standard, the voltage tolerance is controlled to be +/-7% of the rated value. According to the voltage drop formulaCalculating the voltage of the low-voltage side of the transformer of the power distribution network, specifically as follows:
in the formula (I), the compound is shown in the specification,
the voltage value of the high-voltage side of the distribution network transformer in the ith time period of the ith year,
for the loaded active power of the ith year in the t-th period,
for the electric automobile load output value in the t time period of the jth type weather scene,
is the reactive power of the load in the ith time period of the ith year, k
TTransformation ratio of a transformer of the power distribution network; r is
T、x
TRespectively the resistance and reactance value converted to the high voltage side.
(2) Distribution network transformer load rate opportunity constraints
In the formula, Pessi,j,tThe energy storage charging and discharging power is the energy storage charging and discharging power of the ith year and jth class weather scene at the t time period; sTNRated capacity of a transformer of the power distribution network; i ismaxThe load factor is the upper limit value of the transformer load factor of the power distribution network; beta is aIThe confidence coefficient of the load rate of the transformer of the power distribution network is obtained; eta is annual load growth rate; n is the upper limit value of the allowable load growth years; m is the total number of weather scenes; l isTThe service life of the transformer of the power distribution network is prolonged; superscript "-" represents a random variable; pr {. cndot } represents the probability that the event holds.
(3) Charge and discharge power constraint of cluster electric automobile
In the formula, PEVCS-C,iFor the AC charging power of the electric vehicles, PEVCS-D,iAnd D, the direct current charging power is supplied to the cluster electric automobile.
(4) Upper and lower limit constraints of energy storage SOC
SOCmin≤SOCi,j,t≤SOCmax
In the formula, SOCi,j,tThe State of Charge (SOC) of the energy storage in the ith year at the t-th time period, namely the ratio of the residual energy storage capacity to the rated capacity of the energy storage; SOCmax、SOCminRespectively an upper limit value and a lower limit value of the energy storage SOC.
(5) Equality constraint of residual capacity of stored energy
In the formula, Eessi,j,tThe residual capacity of stored energy in the t-th period of i year, Eessi,j,t-1Is the residual capacity of stored energy in the t-1 th time period of i year, Pessci,j,tCharging power for energy storage, Pessdi,j,tFor storing discharge power, ηc、ηdRespectively charging and discharging efficiency of energy storage; and delta t is a charge-discharge time interval.
(6) Energy storage charge-discharge balance constraint
And step 207, solving the double-layer optimization model to obtain a planning result of the power distribution network to be planned.
After the use scene of the transformer is determined, different load conditions need to be considered, and reasonable indoor distribution transformer capacity is selected to achieve the lowest LCC configuration target. The comprehensive simulation result analysis gives a recommended capacity table of the average distribution transformer of the user only considering the influence of the load fluctuation, which is shown in the following table 7:
TABLE 7
| Type of load
|
Oil change S13
|
Dry-change SCB10
|
| Load of residents
|
2.8-5.0
|
2.8-3.5
|
| Public load
|
2.8-5.0
|
2.8-3.5
|
| Merchant load
|
3.1-6.7
|
3.1-4.2 |
In the embodiment, a first load curve and electric vehicle information corresponding to a power distribution network to be planned are obtained, a charging load curve corresponding to each electric vehicle is simulated according to the electric vehicle information, the first load curve and the charging load curve are superposed to obtain a second load curve, a double-layer optimization model for planning the power distribution network is constructed according to an opportunity constraint method based on the second load curve, and finally the double-layer optimization model is solved to obtain a planning result of the power distribution network to be planned. When the power distribution network is planned, uncertainty of the electric automobile is considered when the power distribution network is planned, and the power distribution network is planned by combining electric automobile information of the electric automobile, so that the technical problem that the power distribution network cannot be planned based on electric automobile loads in the conventional power distribution network planning method is solved.
The second aspect of the embodiment of the application provides an embodiment of a double-layer planning device for a power distribution network.
Referring to fig. 6, in an embodiment of the present application, a schematic structural diagram of a power distribution network double-layer planning apparatus includes:
the acquiring unit 601 is configured to acquire a first load curve and electric vehicle information corresponding to a power distribution network to be planned;
the simulation unit 602 is configured to simulate a charging load curve corresponding to each electric vehicle according to the electric vehicle information;
a superimposing unit 603, configured to superimpose the first load curve and the charging load curve to obtain a second load curve;
a constructing unit 604, configured to construct a double-layer optimization model for power distribution network planning according to an opportunity constraint method based on the second load curve;
and the solving unit 605 is configured to solve the double-layer optimization model to obtain a planning result of the power distribution network to be planned.
Further, the simulation unit 602 specifically includes:
the acquiring subunit is used for acquiring a charging demand model corresponding to the electric automobile according to the electric automobile information;
the calculating subunit is used for calculating the corresponding charging required time according to the daily driving mileage corresponding to the electric automobile and the charging demand model;
and the determining subunit is used for determining a charging load curve corresponding to the electric automobile according to the initial charging time, the charging power and the required charging time corresponding to the electric automobile.
Further, the acquiring subunit specifically includes:
the first obtaining subunit is used for obtaining the automobile type corresponding to each electric automobile from the automobile information;
and the second obtaining subunit is used for obtaining a charging demand model corresponding to the automobile type based on the corresponding relation between the automobile type and the charging demand model according to the automobile type.
Specifically, the automobile types include: electric buses, electric taxis and electric private cars.
Specifically, the objective function of the upper-layer optimization planning model in the two-layer optimization model is as follows:
in the formula, CTTo make a distribution transformation full lifecycle cost, CIFor initial investment costs of distribution transformers, CWFor distribution transformation operating loss cost, COFor distribution transformer maintenance cost, CFFor distribution transformation fault costs, CDFor distribution transformation decommissioning disposal costs, XTFor alternative distribution network transformer models, STNThe capacity of the transformer of the alternative power distribution network.
Optionally, the objective function of the lower-layer optimized planning model in the two-layer optimized model is:
in the formula, f is the average active power equivalently injected at the low-voltage side of the distribution network transformer,
and equivalently injecting active power to the low-voltage side of the distribution network transformer in the ith time period of the ith year.
In the embodiment, a first load curve and electric vehicle information corresponding to a power distribution network to be planned are obtained, a charging load curve corresponding to each electric vehicle is simulated according to the electric vehicle information, the first load curve and the charging load curve are superposed to obtain a second load curve, a double-layer optimization model for planning the power distribution network is constructed according to an opportunity constraint method based on the second load curve, and finally the double-layer optimization model is solved to obtain a planning result of the power distribution network to be planned. When the power distribution network is planned, uncertainty of the electric automobile is considered when the power distribution network is planned, and the power distribution network is planned by combining electric automobile information of the electric automobile, so that the technical problem that the power distribution network cannot be planned based on electric automobile loads in the conventional power distribution network planning method is solved.
The third aspect of the embodiments of the present application provides an embodiment of a power distribution network double-layer planning device.
A power distribution network double-layer planning device comprises a processor and a memory; the memory is used for storing the program codes and transmitting the program codes to the processor; the processor is configured to execute the power distribution network two-tier planning method of the first aspect according to instructions in the program code.
A fourth aspect of embodiments of the present application provides an embodiment of a storage medium.
A storage medium for storing program code for performing the power distribution network two-tier planning method of the first aspect.
It is clear to those skilled in the art that, for convenience and brevity of description, the specific working processes of the above-described apparatuses and units may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.
In the several embodiments provided in the present application, it should be understood that the disclosed apparatus and method may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of a unit is only one logical functional division, and there may be other divisions when the actual implementation is performed, for example, a plurality of units or components may be combined or may be integrated into another grid network to be installed, or some features may be omitted or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.
Units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.
In addition, functional units in the embodiments of the present application may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. The integrated unit can be realized in a form of hardware, and can also be realized in a form of a software functional unit.
The integrated unit, if implemented in the form of a software functional unit and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present application may be substantially implemented or contributed to by the prior art, or all or part of the technical solution may be embodied in a software product, which is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present application. And the aforementioned storage medium includes: various media capable of storing program codes, such as a usb disk, a removable hard disk, a Read-only memory (ROM), a Random Access Memory (RAM), a magnetic disk, or an optical disk.
The above embodiments are only used for illustrating the technical solutions of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions in the embodiments of the present application.