Power distribution network backup capacity configuration method and device considering virtual cold and heat pipe network

Abstract

The application discloses a power distribution network reserve capacity configuration method and device considering a virtual cold and heat pipe network, and belongs to the technical field of power distribution networks. The method comprises the following steps: calculating the fault repair time of each pure electric load on a feeder in a power distribution network by using an analytical method; calculating the interruptible time of a user cold / heat load according to a virtual energy storage model and an interruption time influence parameter; and configuring the reserve capacity of the feeder according to the fault repair time of the pure electric load, the interruptible time of the user cold / heat load and a user temperature variation range. On the basis of considering the reliability of the pure electric load, the interruptability of the user side cold / heat load and the comfort of the user, the application appropriately reduces the energy supply reliability standard of the electric refrigeration / heat load, fully utilizes the flexible cold and heat demand of the user and the building thermal inertia, uses part of the power grid reserve capacity as the virtual cold and heat pipe network to supply cold / heat for the user, and improves the utilization efficiency of the power distribution network reserve capacity.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power distribution network, in particular to a power distribution network reserve capacity configuration method and device considering virtual cold and heat pipe network. BACKGROUND

[0002] Under the influence of the flexible cold and heat demand of users and the thermal inertia of building, once the upper power grid fails, the indoor temperature at the user will not change dramatically in a short time, and the power experience of the user to the cold / heat load can be maintained for a period of time. Therefore, compared with pure electric load, the cold / heat load has greater flexibility and certain interruptible characteristics, and can be regarded as a kind of flexible virtual energy storage resource.

[0003] At present, in the construction of comprehensive energy planning and "coal-to-electricity" and other electric energy replacement projects, the reliability of refrigeration / heating electric power load is statistically analyzed according to the same standard as the conventional electric power load, and the short-time interruptibility of cold / heat load is ignored. This way leads to a substantial increase in the redundancy and standby equipment capacity of the comprehensive energy supply network centered on electricity, and the construction cost of the comprehensive energy network is higher than the sum of the cost of building an electric power grid that meets the N-1 requirement and the cost of building a gas and heating pipe network that does not consider the N-1 requirement, which is contrary to the original intention of building a comprehensive energy system.

[0004] In the related art, the patent application with the application number 201810601215.7 discloses a photovoltaic space-time distribution power distribution network system load reserve capacity calculation method, and the implementation steps are as follows: ① Set the required weather types to be divided into K types, such as sunny, overcast, light rain, moderate rain and above, etc.; ② Calculate the time correlation coefficient and the spatial correlation coefficient of different photovoltaic power stations according to the actual value and the predicted value of the historical output of the photovoltaic power station in the research area according to the K types of weather; ③ Substitute the historical actual output data and the historical predicted output data of the photovoltaic power station of the K type weather into the maximum likelihood parameter estimation mathematical model of normal distribution to estimate the maximum prediction error of the photovoltaic output of the K type weather; ④ Calculate the maximum total output prediction error of all photovoltaic power stations in the power supply area of the target power distribution network system and the actual maximum power generation load of the standard power distribution network system; and ⑤ Calculate the load reserve capacity of the target power distribution network system.

[0005] The purpose is to describe the statistical distribution of photovoltaic output prediction error in detail, to reduce the complicated prediction error statistical work under the premise of improving the accuracy of the calculation result, to describe the prediction error statistical distribution of the photovoltaic power station by mathematical method according to the actual value and the measured value of the historical output of the photovoltaic power station by considering the weather factor, to calculate the maximum total output prediction error of all photovoltaic power stations in the power supply area of the target power distribution network system and the actual maximum power generation load of the standard power distribution network system, and to more accurately configure the load reserve.

[0006] In the related art, the invention patent application with the application number 201911052302.2 discloses a power distribution network optimization and connection method considering the grid connection constraint of distributed power supply, and the implementation steps are as follows: ① judging whether the distribution transformer load on each feeder in the region exceeds the feeder capacity; if yes, no need to modify the connection; if not, the network structure needs to be modified; ② judging whether the maximum load of all distribution transformers in the region is greater than the sum of the available capacity of all substations and the maximum output of all distributed power supplies in the region; if yes, it indicates that the feeder capacity overload problem can be solved by network structure modification; if not, it indicates that the feeder capacity overload problem can only be solved by building new lines or newly building substations; ③ establishing a power distribution network modification and optimization model, taking the minimum total modification investment cost as the objective function, and including the distributed power supply grid connection constraint, the distributed power supply grid connection constraint including return current constraint and upper power supply standby capacity constraint; ④ solving the power distribution network modification and optimization model, thereby obtaining the optimal scheme of power distribution network modification and optimization considering the grid connection constraint of distributed power supply, and the corresponding minimum modification engineering cost.

[0007] The purpose is to solve the technical problems of load imbalance and upper power supply accident standby overload caused by the grid connection of distributed power supply, consider the distributed power supply, involve the modification of lines, consider the feeder wiring mode of the power distribution network as single connection, establish a power distribution network modification and optimization model, and solve it by using immune genetic algorithm. SUMMARY

[0008] The technical problem to be solved by the present application is how to improve the utilization efficiency of power network standby capacity and reduce the overall construction and operation cost of power distribution network.

[0009] The present application solves the above technical problems by the following technical means:

[0010] On the one hand, the present application proposes a power distribution network standby capacity configuration method considering virtual cold and heat pipe network, which comprises the following steps:

[0011] The analytical method is used to calculate the fault repair time of each pure electric load on the feeder in the power distribution network;

[0012] According to the virtual energy storage model and the interruption time influence parameter, the interruptible time of the user cold / heat load is calculated, and the interruption time influence parameter includes user comfort, outdoor temperature and building thermodynamic parameter;

[0013] According to the fault repair time of the pure electric load, the interruptible time of the user cold / heat load and the user temperature variation range, the standby capacity of the feeder is configured.

[0014] The application considers the reliability of pure electric load, the interruptibility of user side cold / heat load and the comfort of user, reduces the power supply reliability standard of electric refrigeration / heat load, fully utilizes the flexible cold / heat demand of user and the building thermal inertia, uses part of power grid reserve capacity as virtual cold / heat pipe network to supply cold / heat for user, improves the utilization efficiency of power distribution network reserve capacity, and the maximum theoretical load rate of virtual cold / heat pipe network feedback line is also improved.

[0015] Further, the analytic method is used to calculate the fault repair time of each pure electric load on the feeder in the power distribution network, comprising:

[0016] The type of the power distribution network is determined, and the type of the power distribution network comprises a simple radial main feeder power supply system and a power supply system with branch feeders;

[0017] If the type of the power distribution network is a simple radial main feeder power supply system, the network equivalence method is used to calculate the fault repair time of each pure electric load;

[0018] If the type of the power distribution network is a power supply system with branch feeders, the power supply system with branch feeders is equivalent to a simple radial main feeder power supply system, and then the fault repair time of each pure electric load is calculated.

[0019] Further, the formula for calculating the fault repair time of each pure electric load by the network equivalence method is as follows:

[0020]

[0021] r j =U j / λ j

[0022]

[0023] Wherein, j is a pure electric load node corresponding to a load branch, n is the number of nodes, λ j , r j , U j are the failure rate, fault repair time and annual outage time of the pure electric load node j, λ k ' is the equivalent failure rate of the kth node, λ jl is the failure rate of the load branch line j, λ jt is the equivalent failure rate of the load branch line j, r jk is the outage time of the jth node caused by the fault of the kth node when the jth node is calculated, r jl is the equivalent repair time of the load branch line j, r jt is the equivalent repair time of the transformer on the load branch line j.

[0024] Furthermore, the method also includes:

[0025] In the simple radial feeder power supply system structure, if the k-th component is on the power supply side, the downtime r of the j-th node caused by a fault in the k-th node when calculating the j-th node is... jk The principle for determining it is:

[0026] If there is no sectionalizing switch between the k-th element and the j-th element, then r jk Let be the fault repair time of the k-th component;

[0027] If a sectionalizing switch is provided between the k-th and j-th components, and a tie switch is provided on the feeder after the j-th component, then r jk The larger of the sectionalizing switch operation time and the tie switch switching time;

[0028] If a sectionalizing switch is installed between the k-th and j-th components, but no tie switch is installed on the feeders after the j-th component, then r jk Let be the fault repair time of the k-th component;

[0029] In the simple radial feeder power supply system structure, if the k-th element is farther from the power supply side than the j-th element, the downtime r of the j-th node caused by a fault in the k-th node when calculating the j-th node is... jk The principle for determining it is:

[0030] If there is no sectionalizing switch between the k-th element and the j-th element, then r jk Let be the fault repair time of the k-th component;

[0031] If the k-th element and the j-th element are connected by a sectionalizing switch, then r jk This refers to the operation time of the segmented switch.

[0032] Furthermore, after equating the power supply system with branch feeders to a simple radial main feeder power supply system, the calculation of the fault repair time for each pure electrical load includes:

[0033] In the power supply system with branch feeders, the influence of the branch feeder on the upper feeder is represented as a first equivalent node element and connected in series in the upper feeder. The influence of the load point in the upper feeder corresponding to the branch feeder on the lower feeder is represented as a second equivalent node element and connected in series at the beginning of the lower feeder. The upper feeder is taken as the power supply point, and a simple radial main feeder power supply system is obtained.

[0034] After the power supply system with branch feeders is equivalent to the simple radial main feeder power supply system, the fault repair time of each pure electric load is calculated using the network equivalence method.

[0035] Furthermore, the method also includes:

[0036] If a circuit breaker is installed at the beginning of the branch feeder, the calculation formulas for the reliability parameters of the first equivalent element are as follows:

[0037]

[0038] r e =t1

[0039]

[0040] Where, λ e r e and U e p represents the failure rate, failure repair time, and annual failure time, respectively. b Let t1 be the probability of reliable circuit breaker disconnection, t1 be the node component failure on each branch feeder, and λ be the repair time of the equivalent node in the upstream feeder reflecting the branch feeder's operation time. k ' is the equivalent failure rate of the k-th node;

[0041] If no circuit breaker is installed at the beginning of the branch feeder, the formulas for calculating the reliability parameters of the failure rate of the first equivalent element are as follows:

[0042]

[0043]

[0044]

[0045] Where, r k0 The power outage time at the beginning of the branch feeder caused by the failure of the k-th node is r, where there is no sectionalizing switch between the k-th node and the beginning of the branch feeder. k0 Let r be the equivalent repair time for the k-th node. When there is a segmented switch at the beginning of the branch feeder between the k-th node and the branch feeder, r is... k0 The operating time t1 is the sectionalizing switch operation time.

[0046] Furthermore, the formula for calculating the reliability parameter of the second equivalent element is as follows:

[0047]

[0048]

[0049]

[0050] Where, λ j r j U jThese represent the failure rate, failure repair time, and annual outage time corresponding to pure electric load node j, respectively, and λ. k ' represents the equivalent failure rate of the k-th node, r jk To find the downtime of the j-th node caused by the failure of the k-th node when the j-th node is in operation.

[0051] Furthermore, the calculation of the interruptible time of the user's cooling / heating load based on the virtual energy storage model and the interruption time impact parameters includes:

[0052] The thermal sensation average scaling predictive index is used to evaluate users' comfort level with respect to the indoor environment, and the user's temperature comfort range is obtained.

[0053] Based on the virtual energy storage model, the time it takes for the cooling / heating equipment to change from its original temperature to the user's temperature comfort range limit is calculated, and this time is taken as the interruptible time of the user's cooling / heating load.

[0054] The formula for the virtual energy storage model is expressed as follows:

[0055] Q vir (t)=Q dyn (t)-Q sta (t),

[0056] Q dyn (t)=hf(T in (t)-T1(t))+(βK c f c +0.278c w ρ w V0n(t))

[0057]

[0058] Among them, Q vir Q(t) represents the equivalent energy storage and release power of the building's virtual energy storage at time t. dyn (t) represents the output power of the cooling / heating equipment before the room temperature change, Q sta (t) represents the output power of the cooling / heating equipment after the room temperature changes, T in (t) represents the indoor temperature at time t, T1(t) represents the inner surface temperature of the building envelope at time t, β represents the additional rate of outdoor wind intrusion, and K c f is the heat transfer coefficient of the outer door. c c is the area of ​​the outer door. w For the specific heat of outdoor air, ρ w V represents the outdoor air density. o Let n(t) be the air volume inside the building, n(t) be the number of air changes in time period t, and T be the air volume inside the building. out (t) represents the outdoor temperature at time t, c o For the specific heat of indoor air, ρo Indoor air density;

[0059] The formula for calculating the thermal sensation average scaling prediction index is as follows:

[0060]

[0061] Among them, Г PMV (t) represents the PMV value at time t, M represents the human metabolic rate, and I represents the PMV value at time t. cl The thermal resistance of clothing worn by the human body, T in (t) represents the indoor temperature at time t.

[0062] Furthermore, configuring the backup capacity of the feeder based on the fault repair time of the pure electric load, the interruptibility time of the user's cold / heat load, and the range of user temperature variations includes:

[0063] If the outdoor temperature is within the range of the user's temperature variation, the standby capacity shall be configured in accordance with the N-1 safety principle.

[0064] If the outdoor temperature is not within the range of the user's temperature variation, at t v ≤r j In this case, the user's direct power supply load needs to be configured with standby capacity in accordance with the N-1 safety rule, while the power-to-cooling / heating load does not need to be configured with standby capacity;

[0065] In t v >r j When this occurs, the user's direct power supply load must be configured with standby capacity according to the N-1 safety rule, and the power-to-cooling / heating load must be configured with a certain amount of standby capacity. v r is the interruptible time of the user's cooling / heating load. j The fault repair time for the pure electric load is denoted as .

[0066] On the other hand, the present invention proposes a power distribution network backup capacity configuration device that considers virtual hot and cold pipe networks, the device comprising:

[0067] The first calculation module is used to calculate the fault repair time of each pure electrical load on the feeder in the distribution network using analytical methods;

[0068] The second calculation module is used to calculate the interruptible time of the user's cooling / heating load based on the virtual energy storage model and the interruption time impact parameters, which include user comfort, outdoor temperature and building thermodynamic parameters.

[0069] The backup capacity configuration module is used to configure the backup capacity of the feeder based on the fault repair time of the pure electric load, the interruptible time of the user's cold / hot load, and the range of user temperature changes.

[0070] The advantages of this invention are:

[0071] (1) Based on the reliability of pure electric load, the interruptibility of user-side cooling / heating load and user comfort, this invention makes full use of the user's flexible cooling and heating demand and the thermal inertia of the building by appropriately reducing the energy supply reliability standard of electric cooling / heating load, and using part of the power grid reserve capacity as a virtual cooling / heating network to supply cooling / heating to users, thereby improving the utilization efficiency of the power distribution network reserve capacity. The maximum theoretical load rate of the feeder is also improved after considering the virtual cooling / heating network.

[0072] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0073] Figure 1 This is a flowchart of the power distribution network backup capacity configuration method considering virtual cold and hot pipe networks in the first embodiment of the present invention;

[0074] Figure 2 This is an equivalent diagram of the power distribution network structure in the first embodiment of the present invention;

[0075] Figure 3 This is a schematic diagram of the reuse of power distribution network reserve capacity in the first embodiment of the present invention;

[0076] Figure 4 This is an overall flowchart of the power distribution network backup capacity configuration method considering virtual cold and hot pipe networks in the first embodiment of the present invention;

[0077] Figure 5 This is a structural diagram of a power distribution network backup capacity configuration device considering a virtual cold and hot pipe network in the second embodiment of the present invention. Detailed Implementation

[0078] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0079] like Figure 1 As shown, an embodiment of the present invention proposes a method for configuring standby capacity in a distribution network considering a virtual cold and hot pipe network. The method includes the following steps:

[0080] S10. Calculate the fault repair time of each pure electrical load on the feeder in the distribution network using the analytical method;

[0081] S20. Based on the virtual energy storage model and the interruption time impact parameters, calculate the interruptible time of the user's cooling / heating load. The interruption time impact parameters include user comfort, outdoor temperature, and building thermodynamic parameters.

[0082] S30. Configure the backup capacity of the feeder according to the fault repair time of the pure electric load, the interruptible time of the user's cold / hot load, and the range of user temperature changes.

[0083] It should be noted that, based on the differences in terminal energy demand, the user-side electrical load in this embodiment can be divided into pure electric load, electric cooling load, and electric heating load. Considering the reliability of pure electric load, the interruptibility of user-side cooling / heating load, and user comfort, the power supply reliability standard of electric cooling / heating load is appropriately reduced, the spare capacity of the feeder is reconfigured, and part of the spare capacity is used as a virtual cold / heating network to supply cooling / heating to users, thereby improving the utilization efficiency of the power network's spare capacity.

[0084] In one embodiment, step S10 specifically includes the following steps:

[0085] S11. Determine the type of the power distribution network. The type of the power distribution network includes a simple radial main feeder power supply system and a power supply system with branch feeders.

[0086] It should be noted that a typical simple radial main feeder system consists of circuit breakers, several main feeder sections, load branches, sectionalizing switches, tie lines, and tie switches.

[0087] A complex distribution network refers to a distribution network with branch feeders. For a simple radial distribution network, if some load nodes are connected not to load branches but to branch feeders, and the branch feeders have the same structure as the simple radial network except that they do not have tie lines and tie switches, then a complex distribution network is formed. The branch feeders can still connect to the next level of branch feeders.

[0088] S12. If the type of the distribution network is a simple radial main feeder power supply system, the fault repair time of each pure electric load shall be calculated by the network equivalent method.

[0089] S13. If the power distribution network is a power supply system with branch feeders, then after converting the power supply system with branch feeders into a simple radial main feeder power supply system, calculate the fault repair time of each pure electric load.

[0090] It should be noted that the calculation process for load fault repair time takes into account the impact of equipment such as fuses, circuit breakers, and standby transformers more comprehensively, has a wider range of applicability, is more suitable for systems with circuit breakers in the feeders, and can more realistically reflect the actual situation of the distribution network.

[0091] In one embodiment, when the distribution network is a simple radial main feeder power supply system, during calculations, circuit breakers, each feeder segment, sectionalizing switch, and load branch can be considered as a node. The connections between nodes represent a connection relationship without any attributes; all system faults are determined by the attributes of each node. The node attributes of the circuit breaker are {circuit breaker | failure rate λ′, repair time r′, probability of reliable disconnection p}. b The node attributes of the main feeder segment are {main feeder segment|failure rate λ′, repair time r′}; the node attributes of the sectionalizing switch are {sectionalizing switch|operation time t1, failure rate λ}; the node attributes of the load branch are {load branch|equivalent failure rate λ′, equivalent repair time r′}; the node attributes of the tie line and tie switch are {ticket line and tie switch|ticket line failure rate λ′, tie switch switching time t2}.

[0092] For load branch nodes, since they consist of transformers, load branches, and fuses (optional), it is necessary to perform appropriate analysis to determine their equivalent failure rate. Let p be the probability of reliable fuse operation. f If a fuse is installed at the beginning of load branch j, then the failure rate λ of the equivalent node corresponding to this load branch is... j '=(1-p f )(λ jl +λ jt If the fuse operates 100% reliably, a fault in the load branch will not affect the reliability index of other points on the feeder; if no fuse is installed, it is equivalent to p f If λ = 0, then the reliability parameter corresponding to the node of the load branch on the main line is the failure rate λ. j '=λ jl +λ jt The annual power outage time is u j '=λ jl *r jl +λ jt *r jt The average power outage duration is r j '=u j ' / λ j (When a fuse is installed but not operating with 100% reliability, the equivalent node only changes the failure frequency, while the repair time remains constant.) Where λ jl The failure rate of this load branch line is equal to the line length multiplied by the failure rate per unit length of line, λ. jt r is the equivalent failure rate of the transformer on this load branch. jl r is the equivalent repair time for this line. jt This is the equivalent repair time for the transformer on this branch.

[0093] For a simple radial main feeder system, if double and higher-level component failures are ignored, the reliability index of each load node is calculated using the following formula group one: Let node j be a node corresponding to a load branch, then the failure rate λ corresponding to that load point is... j Fault repair time r j and annual power outage time U j They are respectively:

[0094]

[0095] r j =U j / λ j

[0096]

[0097] In the formula, λ k ' represents the equivalent failure rate of the k-th node, r jk To find the downtime of the j-th node caused by the failure of the k-th node when the j-th node is in operation, n1 is the number of nodes in the simple radiation system.

[0098] In one embodiment, r jk The value of depends on the structure of the system, and the specific determination process is as follows:

[0099] (a) The kth component is on the power supply side

[0100] If there is no sectionalizing switch between the k-th element and the j-th element, then r jk Let r be the fault repair time of the k-th equivalent element; if there is a sectionalizing switch between the k-th element and the j-th element, and a tie switch is provided on the feeder after the j-th element, then r jk The value is taken as the larger of the sectionalizing switch operation time and the tie switch switching time; if there is a sectionalizing switch between the k-th element and the j-th element, but no tie switch is installed on the feeder after the j-th element, then r jk The fault repair time of the k-th equivalent element is still taken as the time.

[0101] (b) The kth element is farther from the power supply side than the jth element.

[0102] If there is no sectionalizing switch between the k-th element and the j-th element, then r jk Let r be the fault repair time of the k-th equivalent element; if a sectionalizing switch is provided between the k-th element and the j-th element, then r jk The time is taken as the operation time of the segmented switch.

[0103] In one embodiment, in step S13, the process of simplifying the power supply system with branch feeders into a simple radial main feeder power supply system is as follows: the influence of the branch feeders on the upper-level feeders in the power supply system with branch feeders is represented as a first equivalent node element and connected in series in the upper-level feeders; the influence of the load point in the upper-level feeder corresponding to the branch feeder on the lower-level feeders is represented as a second equivalent node element and connected in series at the beginning of the lower-level feeders; and the upper-level feeders are used as power supply points to simplify and obtain a simple radial main feeder power supply system.

[0104] Specifically, when dealing with distribution networks of this type, it can first be equivalent to a simple radial distribution network. Reliability assessment of complex distribution networks involves two processes: upward equivalence and downward equivalence. In the upward equivalence process, the impact of a branch feeder on the upper-level feeder is represented by an equivalent node element connected in series in the upper-level feeder; while in the downward equivalence process, the impact of the upper-level feeder on the lower-level feeder is represented by an equivalent node element connected in series at the beginning of the lower-level feeder. The simplification process is as follows: Figure 2 The impact of equivalent components on the upstream feeder can be determined by the failure rate λ of the equivalent components. e Annual failure time U of equivalent components e And the fault repair time r of the equivalent component e Reliability parameters are used to reflect this.

[0105] In one embodiment, the impact of a fault in an equivalent element on a branch feeder on the upstream feeder is as follows:

[0106] (a) When each node component on the branch feeder fails, if a circuit breaker is installed at the beginning of the branch feeder and the probability of the circuit breaker reliably disconnecting is p b The probability that a faulty node component on a branch feeder will cause the upstream feeder to shut down is 1-p. b Therefore, the equivalent node failure rate of the branch feeder in the upper-level feeder should be the sum of the failure rates of all nodes on the branch feeder and 1-p. b The product of; and if the circuit breaker does not disconnect, since the circuit breaker is equipped with a disconnecting switch, therefore, each time a node element on the branch feeder fails, the repair time of the equivalent node of the branch feeder reflected in the upper feeder is the operation time of the disconnecting switch, which is taken as t1; the failure rate λ of the equivalent element of the branch feeder is calculated by the following formula group two. e Fault repair time r e and annual downtime U e :

[0107]

[0108] r e =t1

[0109]

[0110] (b) If no circuit breaker is installed, a fault at any node on the branch feeder will cause the upstream feeder to shut down. Therefore, the fault rate of the equivalent node of the branch feeder reflected in the upstream feeder should be the sum of the fault rates of all nodes on the branch feeder. The downtime depends on the structure of the branch feeder: if a sectionalizing switch is installed between the j-th node and the beginning of the branch feeder, the repair time of the equivalent node of the branch feeder reflected in the upstream feeder when the j-th node fails is the operation time t1 of the sectionalizing switch; if no sectionalizing switch is installed between the j-th node and the beginning of the branch feeder, the repair time of the equivalent node of the branch feeder reflected in the upstream feeder when the j-th node fails is the repair time r of the j-th node. j The failure rate λ of the equivalent element of the branch feeder is calculated using the following formula group three. e Fault repair time U e and annual downtime r e The formulas are as follows:

[0111]

[0112]

[0113]

[0114] Where, r k0 The power outage time at the beginning of the branch feeder caused by the failure of the k-th node is calculated as follows: when there is no sectionalizing switch between the k-th node and the beginning of the branch feeder, r k0 The equivalent repair time for the k-th node; when there is a segmented switch at the beginning of the branch feeder between the k-th node and the branch feeder, r k0 The operating time t1 is the sectionalizing switch operation time.

[0115] Formulas 2 and 3 can ultimately simplify the complex network into a simple radial network. For the simple radial network, formula 1 can be used to obtain the reliability index of each load point on the main feeder.

[0116] If the j-th node on the upper-level feeder corresponds to a branch feeder, and is used as a reliability parameter of the node connected in series at the beginning of the lower-level feeder, then the influence of the upper-level feeder on the lower-level feeder on the complex network can be obtained by using the following set of four formulas.

[0117]

[0118]

[0119]

[0120] Where, λ j r j Uj These represent the failure rate, failure repair time, and annual outage time corresponding to pure electric load node j, respectively, and λ. k ' represents the equivalent failure rate of the k-th node, r jk To find the downtime of the j-th node caused by the failure of the k-th node when the j-th node is in operation.

[0121] In Formulas 2 through 4, n2 represents the number of nodes in the branch feeder. The meanings of the other symbols are the same as in a simple radial network. Reliability assessment of complex distribution networks involves two processes: upward equivalence and downward equivalence. In the upward equivalence process, the impact of the branch feeder on the upper-level feeder is represented by an equivalent node element connected in series in the upper-level feeder. The reliability parameter of this equivalent node element is obtained from Formula 2 or Formula 3. In the downward equivalence process, the impact of the upper-level feeder on the lower-level feeder is represented by an equivalent node element connected in series at the beginning of the lower-level feeder. The reliability parameter of this equivalent node element is obtained from Formula 4. The reliability index of the node corresponding to the branch feeder is obtained from Formula 4. This index is used as the reliability parameter of the node connected in series at the beginning of the lower-level feeder. Then, the upper-level feeder is taken as the power source point, thus forming a new simple radial network. By repeatedly using Formula Group 1, the reliability index of each load point on the feeder can be obtained; by Formula Group 4, the node reliability index corresponding to the feeder and its lower-level branch feeders can be obtained, and so on, level by level, the fault repair time of all load points in the entire complex network can be obtained.

[0122] In one embodiment, step S20 specifically includes the following steps:

[0123] S21. Use the thermal sensation average scaling prediction index to evaluate the user's comfort level with the indoor environment and obtain the user's temperature comfort range.

[0124] S22. Based on the virtual energy storage model, calculate the time it takes for the cooling / heating equipment to change from its original temperature to the user's temperature comfort range limit, and use this as the interruptible time of the user's cooling / heating load.

[0125] The formula for the virtual energy storage model is expressed as follows:

[0126] Q vir (t)=Q dyn (t)-Q sta (t),

[0127] Q dyn (t)=hf(T in (t)-T1(t))+(βK c f c +0.278c w ρ w V0n(t))

[0128]

[0129] Among them, Q vir Q(t) represents the equivalent energy storage and release power of the building's virtual energy storage at time t. dyn (t) represents the output power of the cooling / heating equipment before the room temperature change, Q sta (t) represents the output power of the cooling / heating equipment after the room temperature changes, T in (t) represents the indoor temperature at time t, T1(t) represents the inner surface temperature of the building envelope at time t, β represents the additional rate of outdoor wind intrusion, and K c f is the heat transfer coefficient of the outer door. c c is the area of ​​the outer door. w For the specific heat of outdoor air, ρ w V represents the outdoor air density. o Let n(t) be the air volume inside the building, n(t) be the number of air changes in time period t, and T be the air volume inside the building. out (t) represents the outdoor temperature at time t, c o For the specific heat of indoor air, ρ o Indoor air density;

[0130] The formula for calculating the thermal sensation average scaling prediction index is as follows:

[0131]

[0132] Among them, Г PMV (t) represents the PMV value at time t, M represents the human metabolic rate, and I represents the PMV value at time t. cl The thermal resistance of clothing worn by the human body, T in (t) represents the indoor temperature at time t.

[0133] In calculating the interruptible time of user cooling / heating load, this embodiment fully considers the building's thermal inertia and the user's comfort range, uses PMV values ​​to measure user comfort, and applies a more accurate building thermal balance model, while most studies use a simple first-order equivalent thermal parameter model.

[0134] Specifically, the interruptible time of user cooling / heating load is related to factors such as user comfort, outdoor temperature, and building thermodynamic parameters.

[0135] The indoor air climate is influenced and disturbed by many factors, including external disturbances such as heat loss through doors and windows and outdoor air temperature, as well as internal disturbances such as convective heat transfer between the building envelope and indoor air. A heat balance model based on indoor air is established as shown in the following formula:

[0136] Q1(t)+Q2(t)+Q3(t)=Q4(t)+Q5(t)

[0137]

[0138] Furthermore, building walls exhibit significant thermal inertia, absorbing or releasing heat in response to changes in outdoor temperature. The temperature of their internal nodes also rises or falls accordingly, constituting a dynamic heat transfer process. Since the wall structure is uniform along its surface, and its height and width are much greater than its thickness, this problem is typically modeled in one dimension based on thickness, as shown in the following equation:

[0139]

[0140] In the formula: Q1(t) is the convective heat transfer between the inner surface of the building envelope and the air at time t; Q2(t) is the heat loss through infiltration from building doors and windows at time t; Q3(t) is the increase in sensible heat of the building air per unit time at time t; Q4(t) is the heat exchange power between the cooling and heating equipment and the indoor air at time t; Q5(t) is the heat exchange power between indoor heat sources such as people, cooking utensils, and lighting and the indoor air at time t. T in (t) represents the indoor temperature at time t; T out (t) represents the outdoor temperature at time t; T1(t) represents the inner surface temperature of the building envelope at time t, which can be obtained through the thermal balance model of the building envelope; h represents the convective heat transfer coefficient of the building envelope; f represents the inner surface area of ​​the building envelope; Q d (t) represents the heat consumed when the outer door is opened at time t; Q w (t) represents the heat loss due to the opening of the external window at time t; β represents the additional rate of outdoor wind intrusion, typically taken as 65%; K c f is the heat transfer coefficient of the outer door; c The area is the exterior door area; 0.278 is the unit conversion factor; c w The specific heat of outdoor air is taken as 1.0 kJ / (kg·℃); ρ w Outdoor air density, taken as 1.4 kg / m³ 3 V o Let c be the air volume inside the building; n(t) be the number of air changes per hour during time period t, taken as 0.5 times / h; o ρ is the specific heat of indoor air; o Q represents the indoor air density. k (t) represents the heat exchange power between the electric chiller, bromine chiller, and other equipment and the indoor air at time t; the heat dissipation power per unit area of ​​the indoor heat source is taken as 3.8 W / m². 2 T1(t) is the temperature of the inner surface of the enclosure structure at time t; s is the area of ​​the wall; c is the heat capacity of the wall; ρ is the density of the wall; Δx is the thickness of the wall; λ is the thermal conductivity of the wall; q co q represents the convective heat transfer between the inner surface of the enclosure structure and the air at time t; so At time t, the inner surface receives solar radiation heat through the outer window.

[0141] For building thermal balance models, when other disturbances remain constant, changes in the output power of cooling (heating) equipment will directly affect the indoor temperature T. in The output power Q of the cooling (heating) equipment at time t. dyn When (t) changes, the indoor temperature T of the building in When this also changes, the relationship between the two is as follows:

[0142] Q dyn (t)=hf(T in (t)-T1(t))+(βK c f c +0.278c w ρ w V0n(t))

[0143]

[0144] The equivalent energy storage capacity of building virtual energy storage can be calculated from the difference in output power of cooling (heating) equipment before and after room temperature change:

[0145] Q vir (t)=Q dyn (t)-Q sta (t)

[0146] In the formula, Q vir (t) represents the equivalent energy storage and release power of the building's virtual energy storage at time t. In the cooling scenario, negative values ​​represent energy storage, and positive values ​​represent energy release; in the heating scenario, positive values ​​represent energy storage, and negative values ​​represent energy release. The reason for this difference in sign is that in the cooling scenario, the virtual energy storage stores energy when the user's room temperature decreases and releases energy when the room temperature increases; while in the heating scenario, the opposite is true: the virtual energy storage stores energy when the user's room temperature increases and releases energy when the room temperature decreases.

[0147] In one embodiment, the continuous operating time of virtual energy storage resources after a fault in the upstream power grid is closely related to user comfort. User comfort requirements for the indoor environment can be expressed using the predictive mean vote (PMV) index, a thermal sensation average scale prediction index. This index comprehensively considers factors such as human metabolic rate, clothing worn, and indoor air temperature. The ISO 7730 standard recommends a PMV index range of -0.5 ≤ Γ. PMV (t)≤0.5.

[0148] Based on the calculation formula of the thermal sensation average scaling prediction index and the corresponding PMV index range, the user's temperature comfort range can be obtained. Then, using a virtual energy storage model, the time it takes for the ambient temperature to change from the original temperature to the upper (lower) limit of the comfort temperature after the electric cooling / heating equipment loses power can be calculated. This time is the interruptible time t of the cooling / heating load. v .

[0149] In one embodiment, step S30 includes the following steps:

[0150] S31. If the outdoor temperature is within the range of the user's temperature variation, configure the standby capacity in accordance with the N-1 safety principle.

[0151] S32. If the outdoor temperature is not within the range of the user's temperature variation, at t v ≤r j In this case, the user's direct power supply load needs to be configured with standby capacity in accordance with the N-1 safety rule, while the power-to-cooling / heating load does not need to be configured with standby capacity;

[0152] S33, in t v >r j When this occurs, the user's direct power supply load must be configured with standby capacity according to the N-1 safety rule, and the power-to-cooling / heating load must be configured with a certain amount of standby capacity. v r is the interruptible time of the user's cooling / heating load. j The fault repair time for the pure electric load is denoted as .

[0153] It should be noted that, as Figure 3 As shown, based on the differences in end-user energy demand, the user-side electrical load can be divided into pure electric load, electric cooling load, and electric heating load. Since buildings have thermal inertia and users allow indoor temperatures to vary within a certain range, the supply of electric cooling / heating loads on the user side can be interrupted for a period of time. This characteristic can be utilized to prioritize ensuring the reliability of the user's pure electric load supply, appropriately reducing the reliability requirements for the user's electricity-to-cooling / heating supply. This allows for the reconfiguration of the power network's reserve capacity, with a portion of the reserve capacity used as a virtual cooling / heating network to supply cooling / heating to users.

[0154] The reused reserve capacity, together with the power-to-cooling / heating equipment, constitutes a virtual cooling / heating network. The so-called virtual cooling / heating network is actually a way of reusing the power grid's reserve capacity. By reducing the reliability of the supply to power-to-cooling / heating loads, a portion of the reserve capacity that the power grid originally configured for all loads according to the N-1 safety criterion is reused to supply energy to power-to-cooling / heating loads, thereby improving the utilization efficiency of the power grid's reserve capacity.

[0155] For traditional distribution lines that follow the N-1 safety rule, the relationship between feeder reserve capacity and wiring mode is shown in Table 1 below:

[0156] Table 1

[0157]

[0158]

[0159] After considering virtual heating and cooling networks, for loads directly supplied with electricity, backup should still be provided according to the N-1 safety principle. For loads converted from electricity to cooling or heating, their power reliability can be appropriately reduced, with no backup or only a portion of the power reserved. The specific backup power to be configured is related to the load point fault repair time, the interruptible time of the user's heating / cooling load, and the range of user temperature changes. The specific configuration method is as follows:

[0160] 1) If the outdoor temperature is within the user's acceptable temperature variation range, the user does not need to turn on the power-to-cooling (heating) equipment, and there is no power-to-cooling (heating) load. The user's load is a pure electric load, and all of the user's loads must be configured with standby capacity in accordance with the N-1 safety principle.

[0161] 2) If the outdoor temperature is outside the user's acceptable temperature range, calculate the user's cooling / heating load interruption time t. v Compare this time with the user's fault repair time r j Comparison:

[0162] (a) If t v ≤r j This indicates that during the fault repair period, even with the complete power failure of the electric-to-cooling / heating equipment, the user's indoor temperature can still meet the user's comfort requirements. Therefore, the user's direct power supply load needs to be configured with standby capacity according to the N-1 safety principle, while the electric-to-cooling (heating) load does not need to be configured with standby capacity.

[0163] (b) If t v >r j This indicates that during the fault repair period, under the condition that the power-to-cooling / heating equipment is completely de-energized, the indoor temperature cannot meet the user's comfort requirements. Therefore, the user's direct power supply load needs to be configured with standby capacity in accordance with the N-1 safety principle, and the power-to-cooling (heating) load needs to be configured with a certain amount of standby capacity.

[0164] In one embodiment, for users whose electricity-to-cooling (heating) load requires a certain reserve, this electricity-to-cooling (heating) load can be further divided into reduceable and non-reducable electricity-to-cooling (heating) loads. Reduceable electricity-to-cooling (heating) loads are not configured with reserves, while non-reducable electricity-to-cooling (heating) loads are configured with reserves according to the N-1 safety rule. The non-reducable electricity-to-cooling (heating) load is essentially the minimum amount of electricity-to-cooling / heating load required to meet user comfort needs, such as... Figure 4 As shown.

[0165] Based on the virtual energy storage model, the relationship between the energy release power of the virtual energy storage in a user's building and the virtual energy storage operating time can be derived. Let the energy release time of the virtual energy storage be equal to r. jThe energy release power of the corresponding virtual energy storage can be obtained. At this time, the energy release power value of the virtual energy storage is equal to the power value of the power of the electricity-to-cooling (heating) load that the user can reduce. The difference between the node load power before the fault and the power of the electricity-to-cooling (heating) load that the user can reduce is the size of the standby capacity that the user needs to configure according to the N-1 safety rule.

[0166] In one embodiment, after reconfiguring the reserve capacity of the urban power distribution network using a method that considers a virtual hot and cold network, the utilization efficiency of the reserve capacity and the equipment load rate of the urban power distribution network are improved. Specifically, the maximum theoretical load rate of the feeders is increased after considering the virtual hot and cold network. The calculation process for the maximum theoretical load rate of the feeders after considering the virtual hot and cold network is as follows:

[0167] 1) Input the line parameters of the power supply network, the corresponding component parameters required to calculate the reliability index of the load point, the 24-hour active and reactive power of the load at each node of the network, the 24-hour outdoor temperature, the most comfortable temperature and acceptable temperature variation range of each node user at 24 hours, and the building thermodynamic parameters and building parameters of each node.

[0168] 2) Determine whether the outdoor temperature is within the acceptable temperature range for the node user. If it is within the acceptable temperature range, the power reduction of the cooling / heating load for this node user is zero. If it is not within the acceptable temperature range, calculate the power reduction of the cooling / heating load for the node at this time.

[0169] 3) Increase the load at each node. From step 2), the ratio η of the reducible cooling / heating load at each node to the total load of the node can be obtained. r When increasing the load power of a node, the η of each node r It remains unchanged.

[0170] 4) Set the power of each node to equal the increased power of each node minus the power that can be reduced at this time, perform power flow calculation, and calculate the feeder load rate at this time. If the feeder load rate at this time is still less than the theoretical maximum load rate of the feeder following the N-1 safety criterion, then repeat steps 3) and 4); otherwise, the increased load of each node at this time is the maximum load that the line can bear after considering the virtual hot and cold pipe network.

[0171] 5) Calculate the maximum theoretical load factor of the feeder considering the virtual hot and cold pipe network by measuring the active and reactive power of each node after the load is increased.

[0172] In addition, such as Figure 5 As shown, another embodiment of the present invention proposes a power distribution network backup capacity configuration device considering a virtual cold and hot pipe network, the device comprising:

[0173] The first calculation module 10 is used to calculate the fault repair time of each pure electric load on the feeder in the distribution network using analytical methods.

[0174] The second calculation module 20 is used to calculate the interruptible time of the user's cooling / heating load based on the virtual energy storage model and the interruption time impact parameters, wherein the interruption time impact parameters include user comfort, outdoor temperature and building thermodynamic parameters.

[0175] The backup capacity configuration module 30 is used to configure the backup capacity of the feeder based on the fault repair time of the pure electric load, the interruptible time of the user's cold / hot load, and the range of user temperature changes.

[0176] It should be noted that this embodiment makes full use of users' flexible heating and cooling needs and the thermal inertia of buildings, using part of the power grid's reserve capacity as a virtual heating and cooling network to supply cooling / heating to users, thereby improving the utilization efficiency of the power distribution network's reserve capacity.

[0177] In one embodiment, the first computing module 10 includes:

[0178] The determination unit is used to determine the type of the power distribution network, which includes a simple radial main feeder power supply system and a power supply system with branch feeders.

[0179] The first calculation unit is used to calculate the fault repair time of each pure electric load in the simple radial main feeder power supply system of the power distribution network using the network equivalent method.

[0180] The second calculation unit is used to calculate the fault repair time of each pure electric load after the power distribution network is a power supply system with branch feeders, which is equivalent to a simple radial main feeder power supply system.

[0181] In one embodiment, the formula for calculating the fault repair time of each pure electric load using the network equivalence method is expressed as follows:

[0182]

[0183] r j =U j / λ j

[0184]

[0185] Where j is the pure electric load node corresponding to a load branch, n is the number of nodes, and λ j r j U j These represent the failure rate, failure repair time, and annual outage time corresponding to pure electric load node j, respectively, and λ. k ' is the equivalent failure rate of the k-th node, λ jl Let λ be the failure rate of the load branch line j.jt r is the equivalent failure rate of load branch line j. jk To calculate the downtime of the j-th node caused by the failure of the k-th node when the j-th node is at node j, r jl r is the equivalent repair time of the load branch line j. jt The equivalent repair time is the time for the transformer on the load branch line j.

[0186] In one embodiment, in the simple radial feeder power supply system structure, if the k-th element is on the power supply side, the downtime r of the j-th node caused by the failure of the k-th node when calculating the j-th node is... jk The principle for determining it is:

[0187] If there is no sectionalizing switch between the k-th element and the j-th element, then r jk Let be the fault repair time of the k-th component;

[0188] If a sectionalizing switch is provided between the k-th and j-th components, and a tie switch is provided on the feeder after the j-th component, then r jk The larger of the sectionalizing switch operation time and the tie switch switching time;

[0189] If a sectionalizing switch is installed between the k-th and j-th components, but no tie switch is installed on the feeders after the j-th component, then r jk Let be the fault repair time of the k-th component;

[0190] In the simple radial feeder power supply system structure, if the k-th element is farther from the power supply side than the j-th element, the downtime r of the j-th node caused by a fault in the k-th node when calculating the j-th node is... jk The principle for determining it is:

[0191] If there is no sectionalizing switch between the k-th element and the j-th element, then r jk Let be the fault repair time of the k-th component;

[0192] If the k-th element and the j-th element are connected by a sectionalizing switch, then r jk This refers to the operation time of the segmented switch.

[0193] In one embodiment, the second computing unit is specifically used for:

[0194] In the power supply system with branch feeders, the influence of the branch feeder on the upper feeder is represented as a first equivalent node element and connected in series in the upper feeder. The influence of the load point in the upper feeder corresponding to the branch feeder on the lower feeder is represented as a second equivalent node element and connected in series at the beginning of the lower feeder. The upper feeder is taken as the power supply point, and a simple radial main feeder power supply system is obtained.

[0195] After the power supply system with branch feeders is equivalent to the simple radial main feeder power supply system, the fault repair time of each pure electric load is calculated using the network equivalence method.

[0196] In one embodiment, if a circuit breaker is provided at the beginning of the branch feeder, the calculation formulas for the reliability parameters of the first equivalent element are as follows:

[0197]

[0198] r e =t1

[0199]

[0200] Where, λ e r e and U e p represents the failure rate, failure repair time, and annual failure time, respectively. b Let t1 be the probability of reliable circuit breaker disconnection, t1 be the node component failure on each branch feeder, and λ be the repair time of the equivalent node in the upstream feeder reflecting the branch feeder's operation time. k ' is the equivalent failure rate of the k-th node;

[0201] If no circuit breaker is installed at the beginning of the branch feeder, the formulas for calculating the reliability parameters of the failure rate of the first equivalent element are as follows:

[0202]

[0203]

[0204]

[0205] Where, r k0 The power outage time at the beginning of the branch feeder caused by the failure of the k-th node is r, where there is no sectionalizing switch between the k-th node and the beginning of the branch feeder. k0 Let r be the equivalent repair time for the k-th node. When there is a segmented switch at the beginning of the branch feeder between the k-th node and the branch feeder, r is... k0 The operating time t1 is the sectionalizing switch operation time.

[0206] The formula for calculating the reliability parameters of the second equivalent element is:

[0207]

[0208]

[0209]

[0210] Where, λ j r j U j These represent the failure rate, failure repair time, and annual outage time corresponding to pure electric load node j, respectively, and λ. k ' represents the equivalent failure rate of the k-th node, r jk To find the downtime of the j-th node caused by the failure of the k-th node when the j-th node is in operation.

[0211] In one embodiment, the second computing module 20 includes:

[0212] The comfort zone calculation unit is used to evaluate the user's comfort level with the indoor environment using the thermal sensation average scale prediction index, and obtain the user's temperature comfort zone.

[0213] The interruption time calculation unit is used to calculate, based on the virtual energy storage model, the time it takes for the cooling / heating equipment to change from its original temperature to the user's temperature comfort range limit, as the interruptible time of the user's cooling / heating load;

[0214] The formula for the virtual energy storage model is expressed as follows:

[0215] Q vir (t)=Q dyn (t)-Q sta (t),

[0216] Q dyn (t)=hf(T in (t)-T1(t))+(βK c f c +0.278c w ρ w V0n(t))

[0217]

[0218] Among them, Q vir Q(t) represents the equivalent energy storage and release power of the building's virtual energy storage at time t. dyn (t) represents the output power of the cooling / heating equipment before the room temperature change, Q sta (t) represents the output power of the cooling / heating equipment after the room temperature changes, T in (t) represents the indoor temperature at time t, T1(t) represents the inner surface temperature of the building envelope at time t, β represents the additional rate of outdoor wind intrusion, and K c f is the heat transfer coefficient of the outer door. c c is the area of ​​the outer door. w For the specific heat of outdoor air, ρ w V represents the outdoor air density. o Let n(t) be the air volume inside the building, n(t) be the number of air changes in time period t, and T be the air volume inside the building.out (t) represents the outdoor temperature at time t, c o For the specific heat of indoor air, ρ o Indoor air density;

[0219] The formula for calculating the thermal sensation average scaling prediction index is as follows:

[0220]

[0221] Among them, Г PMV (t) represents the PMV value at time t, M represents the human metabolic rate, and I represents the PMV value at time t. cl The thermal resistance of clothing worn by the human body, T in (t) represents the indoor temperature at time t.

[0222] In one embodiment, the standby capacity configuration module 30 is specifically used for:

[0223] If the outdoor temperature is within the range of the user's temperature variation, the standby capacity shall be configured in accordance with the N-1 safety principle.

[0224] If the outdoor temperature is not within the range of the user's temperature variation, at t v ≤r j In this case, the user's direct power supply load needs to be configured with standby capacity in accordance with the N-1 safety rule, while the power-to-cooling / heating load does not need to be configured with standby capacity;

[0225] In t v >r j When this occurs, the user's direct power supply load must be configured with standby capacity according to the N-1 safety rule, and the power-to-cooling / heating load must be configured with a certain amount of standby capacity. v r is the interruptible time of the user's cooling / heating load. j The fault repair time for the pure electric load is denoted as .

[0226] It should be noted that other embodiments or implementation methods of the power distribution network standby capacity configuration device considering virtual cold and hot pipe networks described in this invention can refer to the above-mentioned method embodiments, and will not be repeated here.

[0227] It should be noted that the logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include: an electrical connection having one or more wires (electronic device), a portable computer disk drive (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Alternatively, the computer-readable medium may be paper or other suitable media on which the program can be printed, since the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in a computer memory.

[0228] It should be understood that various parts of the present invention can be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0229] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0230] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0231] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A method for configuring standby capacity in a distribution network considering a virtual cold and hot pipe network, characterized in that, The method includes: The analytical method is used to calculate the fault repair time of each pure electrical load on the feeder in the distribution network, including: determining the type of the distribution network, which includes a simple radial main feeder power supply system and a power supply system with branch feeders; if the type of the distribution network is a simple radial main feeder power supply system, then the network equivalent method is used to calculate the fault repair time of each pure electrical load; if the type of the distribution network is a power supply system with branch feeders, then the power supply system with branch feeders is equivalent to a simple radial main feeder power supply system before calculating the fault repair time of each pure electrical load. Based on the virtual energy storage model and the interruption time impact parameters, the interruptible time of the user's cooling / heating load is calculated. The interruption time impact parameters include user comfort, outdoor temperature, and building thermodynamic parameters. Configure the backup capacity of the feeder based on the fault repair time of the pure electric load, the interruptible time of the user's cold / heat load, and the range of user temperature changes; The formula for calculating the fault repair time of each pure electric load using the network equivalent method is expressed as follows: in, j For a load branch, the corresponding pure electric load node, n 1 represents the number of nodes in a simple radiative system. λ j , r j , U j These are pure electric load nodes. j The corresponding failure rate, fault repair time, and annual power outage time. For the first k The equivalent failure rate of each node. For load branch lines j Failure rate, For load branch lines j The equivalent failure rate, r jk In order to achieve the first j When the node is... k The failure of the first node caused the first j The downtime of each node, For load branch lines j Equivalent repair time, For load branch lines j The equivalent repair time of the transformer.

2. The method for configuring standby capacity of a distribution network considering a virtual cold and hot pipe network as described in claim 1, characterized in that, The method further includes: In a simple radial feeder power supply system structure, if the first k The component is on the power supply side, and the first requirement is... j When the node is... k The failure of the first node caused the first j Downtime of each node r jk The principle for determining it is: If the first k The component and the first j If there is no sectionalizing switch between the components, then r jk For the first k The troubleshooting time for each component; If the first k The component and the first j There are sectional switches between the components, and the first... j If a connecting switch is installed on the feeder after each component, then... r jk The larger of the sectionalizing switch operation time and the tie switch switching time; If the first k The component and the first j There are sectional switches between the components, but the first one... j If a tie switch is not installed on the feeder after the component, then... r jk For the first k The troubleshooting time for each component; In the simple radial feeder power supply system structure, if the first k The component is compared to the first j The component is far from the power supply side, and the requirement is... j When the node is... k The failure of the first node caused the first j Downtime of each node r jk The principle for determining it is: If the first k The component and the first j If there is no sectionalizing switch between the components, then r jk For the first k The troubleshooting time for each component; If the k The component and the first j If each component is equipped with a sectionalizing switch, then r jk This refers to the operation time of the segmented switch.

3. The method for configuring standby capacity of a distribution network considering a virtual cold and hot pipe network as described in claim 1, characterized in that, After equating the power supply system with branch feeders to a simple radial main feeder power supply system, the fault repair time for each pure electrical load is calculated, including: In the power supply system with branch feeders, the influence of the branch feeder on the upper feeder is represented as a first equivalent node element and connected in series in the upper feeder. The influence of the load point in the upper feeder corresponding to the branch feeder on the lower feeder is represented as a second equivalent node element and connected in series at the beginning of the lower feeder. The upper feeder is taken as the power supply point, and a simple radial main feeder power supply system is obtained. After the power supply system with branch feeders is equivalent to the simple radial main feeder power supply system, the fault repair time of each pure electric load is calculated using the network equivalence method.

4. The method for configuring standby capacity of a distribution network considering a virtual cold and hot pipe network as described in claim 3, characterized in that, The method further includes: If a circuit breaker is installed at the beginning of the branch feeder, the calculation formulas for the reliability parameters of the first equivalent node element are as follows: in, λ e , r e and U e These represent the failure rate, failure repair time, and annual downtime, respectively. p b The probability that the circuit breaker will reliably disconnect. t 1 represents the repair time of the equivalent node on each branch feeder in case of a node component failure. The repair time of this equivalent node in the upstream feeder is the operation time of the disconnecting switch. For the first k The equivalent failure rate of each node. n 2 represents the number of nodes in the branch feeder; If no circuit breaker is installed at the beginning of the branch feeder, the formulas for calculating the reliability parameters of the failure rate of the first equivalent node element are as follows: in, r k0 For the first k The power outage time at the beginning of the branch feeder caused by the failure of a node is as follows: k When there is no sectionalizing switch at the beginning of each node and branch feeder. r k0 For the first k The equivalent repair time of the nth node, when the nth node... k When there is a sectionalizing switch at the beginning of each node and branch feeder. r k0 Operating time of the sectionalizing switch t 1.

5. The method for configuring standby capacity of a distribution network considering a virtual hot and cold pipe network as described in claim 3, characterized in that, The formula for calculating the reliability parameters of the second equivalent node element is as follows: in, λ j , r j , U j These are pure electric load nodes. j The corresponding failure rate, fault repair time, and annual power outage time. For the first k The equivalent failure rate of each node. r jk In order to achieve the first j When the node is... k The failure of the first node caused the first j The downtime of each node, n 2 represents the number of nodes in the branch feeder.

6. The method for configuring standby capacity of a distribution network considering a virtual cold and hot pipe network as described in claim 1, characterized in that, The calculation of the interruptible time of user cooling / heating load based on the virtual energy storage model and interruption time impact parameters includes: The thermal sensation average scaling predictive index is used to evaluate users' comfort level with respect to the indoor environment, and the user's temperature comfort range is obtained. Based on the virtual energy storage model, the time it takes for the cooling / heating equipment to change from its original temperature to the user's temperature comfort range limit is calculated, and this time is taken as the interruptible time of the user's cooling / heating load. The formula for the virtual energy storage model is expressed as follows: ， in, Q vir ( t )for t The equivalent energy storage and release capacity of virtual energy storage in buildings at any given time. Q dyn ( t The output power of the cooling / heating equipment before the room temperature changes. This represents the output power of the cooling / heating equipment after a change in room temperature. T in ( t )for t Constant indoor temperature T 1( t )for t Constant temperature of the inner surface of the building envelope β Additional rate for outdoor wind intrusion, K c The heat transfer coefficient of the outer door. f c For the area of ​​the outer door, c w For the specific heat of outdoor air, ρ w Outdoor air density, V o The volume of air inside a building. n ( t )for t Number of air exchanges per period T out ( t )for t outdoor temperature at all times c o For the specific heat of indoor air, ρ o Indoor air density; The formula for calculating the thermal sensation average scaling prediction index is as follows: Among them, Г PMV ( t )for t Moment PMV Indicator value, M The human body's metabolic rate. I cl Thermal resistance of clothing worn by the human body for t The indoor temperature at any given time.

7. The method for configuring standby capacity of a distribution network considering a virtual cold and hot pipe network as described in claim 1, characterized in that, The configuration of the feeder's standby capacity based on the fault repair time of the pure electric load, the interruptibility time of the user's cold / heat load, and the user's temperature variation range includes: If the outdoor temperature is within the range of the user's temperature variation, the standby capacity shall be configured in accordance with the N-1 safety principle. If the outdoor temperature is not within the range of temperature variation for the user, t v ≤ r j In this case, the user's direct power supply load needs to be configured with standby capacity in accordance with the N-1 safety rule, while the power-to-cooling / heating load does not need to be configured with standby capacity; exist t v > r j In this case, the user's direct power supply load must be configured with reserve capacity according to the N-1 safety rule, and the power-to-cooling / heating load must be configured with a certain reserve capacity. t v The interruptible time of the user's cooling / heating load. r j The fault repair time for the pure electric load is denoted as .

8. A power distribution network backup capacity configuration device considering a virtual hot and cold water pipe network, characterized in that, For performing the distribution network standby capacity configuration method considering virtual hot and cold piping networks as described in any one of claims 1-7, the apparatus comprises: The first calculation module is used to calculate the fault repair time of each pure electrical load on the feeder in the distribution network using analytical methods; The second calculation module is used to calculate the interruptible time of the user's cooling / heating load based on the virtual energy storage model and the interruption time impact parameters, which include user comfort, outdoor temperature and building thermodynamic parameters. The backup capacity configuration module is used to configure the backup capacity of the feeder based on the fault repair time of the pure electric load, the interruptible time of the user's cold / hot load, and the range of user temperature changes.

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