Relay protection device setting optimization method and system of new energy power distribution network, terminal equipment and storage medium

Abstract

The invention discloses a relay protection device setting optimization method and system for a new energy power distribution network, terminal equipment and a storage medium, and belongs to the technical field of relay protection device setting optimization. The method comprises the following steps: acquiring basic data of the new energy power distribution network; according to the basic data, by taking maximization of sensitivity of each relay protection device in the new energy power distribution network and minimization of misoperation and rejection rate as targets, constructing a target function, time coordination constraint and setting upper and lower limit constraint of relay protection device setting optimization; and solving the target function under the constraints, generating the action time of each relay protection device and the sensitivity coefficient of each relay protection device, and setting and optimizing each relay protection device of the new energy power distribution network. Therefore, by implementing the method and the device, the problem that safe and stable operation of the power distribution network is affected due to the fact that the misoperation or refusing phenomenon is not considered during setting optimization in the prior art and the refusing or misoperation phenomenon possibly occurs during setting optimization can be solved.

Description

Technical Field

[0001] The present invention relates to the technical field of relay protection device setting optimization, and particularly relates to a method, system, terminal device and storage medium for optimizing the setting of relay protection devices in a new energy distribution network. Background Art

[0002] With the adjustment of the global energy structure and the promotion of the dual-carbon goal, the new power system is accelerating its development towards a high proportion of new energy. As a key link for carrying wind energy and photovoltaic distributed power sources, the operating characteristics of the new energy distribution network have changed significantly compared with traditional distribution networks. Due to the randomness, volatility and uncertainty of new energy output, the power flow distribution of the new energy distribution network shows dynamic change characteristics, making the relay protection setting face greater challenges.

[0003] Currently, traditional relay protection setting calculation methods mainly rely on fixed power flow and short-circuit calculation models and complete the setting parameter allocation in a centralized calculation environment. However, in a new energy distribution network, new energy generation is greatly affected by natural conditions (such as light intensity, wind speed, etc.), which will cause changes in the power flow distribution and short-circuit current level of the distribution network, resulting in refusal to operate or misoperation phenomena. The traditional relay protection setting calculation methods do not consider the refusal to operate or misoperation phenomena in setting optimization, resulting in possible refusal to operate or misoperation phenomena when the obtained setting results are used to optimize the setting of relay protection devices, thus affecting the safe and stable operation of the distribution network. Summary of the Invention

[0004] Embodiments of the present invention provide a method, system, terminal device and storage medium for optimizing the setting of relay protection devices in a new energy distribution network, which can solve the problem that the existing technology does not consider the refusal to operate or misoperation phenomena in setting optimization of relay protection devices, resulting in possible refusal to operate or misoperation phenomena when the obtained setting results are used to optimize the setting of relay protection devices, thus affecting the safe and stable operation of the distribution network, and improve the operation safety of the distribution network.

[0005] An embodiment of the present invention provides a method for optimizing the setting of relay protection devices in a new energy distribution network, including:

[0006] Obtain the basic data of the new energy distribution network; wherein, the basic data includes: the number of relay protection devices, the index of each relay protection device, the reference action time of each relay protection device, the minimum action time difference between upper and lower relay protection devices, the lower limit of the action time of the relay protection device, and the upper limit of the action time of the relay protection device;

[0007] Based on the above basic data, aiming at maximizing the sensitivity of each relay protection device and minimizing the misoperation and refusal rates in the new - energy distribution network, a target function for the setting optimization of relay protection devices is constructed; and the time - coordination constraint and the setting upper - and - lower - limit constraint of the target function are constructed according to the above basic data.

[0008] Under the constraints of the time - coordination constraint and the setting upper - and - lower - limit constraint, the target function is solved to generate the operating time of each relay protection device and the sensitivity coefficient of each relay protection device when the sensitivity of each relay protection device in the new - energy distribution network is maximized and the misoperation and refusal rates are minimized.

[0009] The relay protection devices in the new - energy distribution network are set and optimized with the operating time of each relay protection device and the sensitivity coefficient of each relay protection device when the sensitivity of each relay protection device in the new - energy distribution network is maximized and the misoperation and refusal rates are minimized.

[0010] Furthermore, the target function is specifically:

[0011]

[0012] where minA indicates that the goal of the target function is to minimize the target function A; m represents the number of relay protection devices; x represents the index of the x - th relay protection device; T ref,x represents the reference operating time of the x - th relay protection device; T x represents the operating time of the x - th relay protection device; S x represents the sensitivity coefficient of the x - th relay protection device; w1 represents the weight coefficient of the operating - time error term; w2 represents the weight coefficient of the reciprocal of the sensitivity.

[0013] Furthermore, the time - coordination constraint is specifically:

[0014] T x+1 -T x ≥ΔT min ;

[0015] where T x represents the operating time of the x - th relay protection device; T x+1 represents the operating time of the (x + 1) - th relay protection device, T x+1 is the upper - level relay protection device of T x ; ΔT min represents the minimum operating - time difference between the upper - and - lower - level relay protection devices.

[0016] Furthermore, the setting upper - and - lower - limit constraint is specifically:

[0017] T min ≤T x ≤Tmax ;

[0018] Among them, T min represents the lower limit of the operating time of the relay protection device; T x represents the operating time of the x-th relay protection device; T max represents the upper limit of the operating time of the relay protection device.

[0019] Furthermore, when maximizing the sensitivity and minimizing the misoperation and refusal rates of each relay protection device in the new energy distribution network, after the operating time of each relay protection device and the sensitivity coefficient of each relay protection device, it further includes:

[0020] Obtain the electrical parameters of the new energy distribution network at the current moment; among them, the electrical parameters include: the load power demand at the current moment, the new energy output power at the current moment, the nodal admittance matrix, the equivalent impedance at the fault point, and the fault type at the fault point; the new energy output power includes the output power of wind power generation equipment and the output power of photovoltaic power generation equipment; the fault types include single-phase grounding, two-phase short circuit, and three-phase short circuit;

[0021] Calculate the voltage values of each node, the injected current of each node, the complex power between nodes, and the magnitude of the current flowing through the fault point when the fault occurs at the current moment according to the electrical parameters and the preset power flow and short-circuit analysis model of the power grid;

[0022] If any one of the voltage values of each node, the injected current of each node, the complex power between nodes, and the magnitude of the current flowing through the fault point when the fault occurs at the current moment does not meet the preset threshold requirements, adjust the weight coefficients of the objective function and re-solve the objective function; among them, the weight coefficients include: the weight coefficient of the operating time error term and the weight coefficient of the reciprocal of the sensitivity.

[0023] Furthermore, the preset power flow and short-circuit analysis model of the power grid is specifically:

[0024]

[0025] Among them, represents the preset power flow and short-circuit analysis model of the power grid; V(t) represents the voltage values of all nodes at time t; P load (t) represents the load power demand at time t; P RES (t) represents the new energy output power at time t; Y represents the nodal admittance matrix; f1(·) represents the power flow calculation function; I(t) represents the injected current of all nodes at time t; V i (t) represents the voltage value of node i at time t; represents the conjugate complex number of the current from node i to node j at time t; S ij(t) represents the complex power from node i to node j at time t; Z eq represents the equivalent impedance at the fault point; I sc (t) represents the magnitude of the current flowing through the fault point at the time of fault occurrence at time t; f2(·) represents the short-circuit current solution function.

[0026] Based on the above method embodiment, the present invention correspondingly provides a system embodiment;

[0027] An embodiment of the present invention correspondingly provides a relay protection device setting optimization system for a new energy distribution network, including: a data acquisition module, a target function and constraint condition construction module, a target function solution module, and a setting optimization module;

[0028] The data acquisition module is used to acquire the basic data of the new energy distribution network; wherein, the basic data includes: the number of relay protection devices, the index of each relay protection device, the reference action time of each relay protection device, the minimum action time difference between upper and lower relay protection devices, the lower limit of the action time of the relay protection device, and the upper limit of the action time of the relay protection device;

[0029] The target function and constraint condition construction module is used to construct a target function for relay protection device setting optimization with the goal of maximizing the sensitivity of each relay protection device in the new energy distribution network and minimizing the misoperation and refusal rate according to the basic data; and construct the time coordination constraint and setting upper and lower limit constraints of the target function according to the basic data;

[0030] The target function solution module is used to solve the target function under the constraints of the time coordination constraint and the setting upper and lower limit constraints, and generate the action time of each relay protection device and the sensitivity coefficient of each relay protection device when the sensitivity of each relay protection device in the new energy distribution network is maximized and the misoperation and refusal rate is minimized;

[0031] The setting optimization module is used to perform setting optimization on each relay protection device of the new energy distribution network with the action time of each relay protection device and the sensitivity coefficient of each relay protection device when the sensitivity of each relay protection device in the new energy distribution network is maximized and the misoperation and refusal rate is minimized.

[0032] Further, the target function is specifically:

[0033]

[0034] Among them, minA represents that the goal of the target function is to minimize the target function A; m represents the number of relay protection devices; x represents the index of the xth relay protection device; T ref,x represents the reference action time of the xth relay protection device; T xRepresents the operating time of the x-th relay protection device; S x Represents the sensitivity coefficient of the x-th relay protection device; w1 represents the weight coefficient of the operating time error term; w2 represents the weight coefficient of the reciprocal of the sensitivity.

[0035] Another embodiment of the present invention provides a terminal device, including a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor. When the processor executes the computer program, it implements a method for optimizing the setting of a relay protection device in a new energy distribution network as described in the above-mentioned embodiment of the invention.

[0036] Another embodiment of the present invention provides a storage medium, which includes a stored computer program. When the computer program runs, it controls the device where the storage medium is located to execute a method for optimizing the setting of a relay protection device in a new energy distribution network as described in the above-mentioned embodiment of the invention.

[0037] By implementing the present invention, the following beneficial effects are achieved:

[0038] The present invention provides a method, system, terminal device, and storage medium for optimizing the setting of a relay protection device in a new energy distribution network. The method includes: obtaining the basic data of the new energy distribution network, and then, with the goal of maximizing the sensitivity of each relay protection device in the new energy distribution network and minimizing the misoperation and refusal rates, constructing an objective function for optimizing the setting of the relay protection device, and constructing the time coordination constraint and the upper and lower limits constraint of the objective function according to the basic data. By adding the goal of minimizing the misoperation and refusal rates when constructing the objective function, the operating time of each relay protection device and the sensitivity coefficient of each relay protection device obtained by solving based on the objective function and its constraint conditions can meet the goal of maximizing the sensitivity of each relay protection device in the new energy distribution network and minimizing the misoperation and refusal rates. Therefore, when using the data obtained under this goal to optimize the setting of each relay protection device in the new energy distribution network, the possibility of misoperation or refusal can be reduced, and thus the safe and stable operation of the new energy distribution network can be realized. Description of the Drawings

[0039] Figure 1 Is a flowchart showing a method for optimizing the setting of a relay protection device in a new energy distribution network provided by an embodiment of the present invention.

[0040] Figure 2 Is a structural diagram showing a system for optimizing the setting of a relay protection device in a new energy distribution network provided by an embodiment of the present invention. Detailed Embodiments

[0041] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0042] As Figure 1 shown, to solve the problem that the prior art does not consider the misoperation or refusal-to-operate phenomenon in the setting optimization of relay protection devices, resulting in the possible occurrence of refusal-to-operate or misoperation phenomena when the obtained setting results are used to optimize the setting of relay protection devices, thus affecting the safe and stable operation of the distribution network, an embodiment of the present invention provides a method for optimizing the setting of relay protection devices in a new energy distribution network, including:

[0043] Step S1: Obtain the basic data of the new energy distribution network; wherein, the basic data includes: the number of relay protection devices, the index of each relay protection device, the reference operating time of each relay protection device, the minimum operating time difference between upper and lower level relay protection devices, the lower limit of the operating time of the relay protection device, and the upper limit of the operating time of the relay protection device;

[0044] Step S2: According to the basic data, with the goal of maximizing the sensitivity of each relay protection device in the new energy distribution network and minimizing the misoperation and refusal-to-operate rate, construct an objective function for optimizing the setting of relay protection devices; and construct time coordination constraints and setting upper and lower limit constraints for the objective function according to the basic data;

[0045] Step S3: Under the constraints of the time coordination constraints and the setting upper and lower limit constraints, solve the objective function to generate the operating time of each relay protection device and the sensitivity coefficient of each relay protection device when the sensitivity of each relay protection device in the new energy distribution network is maximized and the misoperation and refusal-to-operate rate is minimized;

[0046] Step S4: Optimize the setting of each relay protection device in the new energy distribution network with the operating time of each relay protection device and the sensitivity coefficient of each relay protection device when the sensitivity of each relay protection device in the new energy distribution network is maximized and the misoperation and refusal-to-operate rate is minimized.

[0047] For step S1, obtain the basic data of the new energy distribution network. The basic data includes the number of relay protection devices in the new energy distribution network, the index of each relay protection device, the reference operating time of each relay protection device, the minimum operating time difference between the upper and lower relay protection devices (the upper and lower relay protection devices are determined according to the protection scope, operating logic, and positional relationship of the relay protection devices in the new energy distribution network. For example, the protection scope of the upper relay protection device includes the protection scope of the lower relay protection device), the lower limit of the operating time of the relay protection device, and the upper limit of the operating time of the relay protection device.

[0048] For step S2, based on the basic data obtained in step S1, with the goal of maximizing the sensitivity of each relay protection device in the new energy distribution network and minimizing the misoperation and refusal rates, construct an objective function for the setting optimization of the relay protection device; and construct the time coordination constraint and setting upper and lower limit constraints of the objective function according to the basic data.

[0049] In a preferred embodiment, the objective function is specifically:

[0050]

[0051] Among them, minA indicates that the goal of the objective function is to minimize the objective function A; m represents the number of relay protection devices; x represents the index of the xth relay protection device; T ref,x represents the reference operating time of the xth relay protection device; T x represents the operating time of the xth relay protection device; S x represents the sensitivity coefficient of the xth relay protection device; w1 represents the weight coefficient of the operating time error term; w2 represents the weight coefficient of the reciprocal of the sensitivity term.

[0052] Specifically, in the above objective function, the weight coefficient w1 of the operating time error term and the weight coefficient w2 of the reciprocal of the sensitivity term will be set with an initial value when initially constructing the above objective function. When the operating time or sensitivity coefficient obtained by solving the objective function does not meet the requirements, it can be adjusted, and its adjustment will be described in the subsequent steps. The sensitivity coefficient S x is used to measure the sensitivity of the relay protection device to faults. It usually needs to be greater than a set sensitivity threshold, such as 1.2, to ensure that the relay protection device can quickly respond to faults and trigger protection actions when a fault occurs. If the obtained sensitivity coefficient of the relay protection device is not greater than 1.2, then after adjusting the w2 weight in the objective function, the objective function can be re-solved to adjust its sensitivity term so that the sensitivity coefficient of the relay protection device meets the sensitivity threshold requirements.

[0053] In a preferred embodiment, the time coordination constraint is specifically as follows:

[0054] T x+1 -T x ≥ΔT min ;

[0055] Wherein, T x represents the operating time of the xth relay protection device; T x+1 represents the operating time of the (x + 1)th relay protection device, and T x+1 is the superior relay protection device of T x ; ΔT min represents the minimum operating time difference between the superior and inferior relay protection devices.

[0056] In a preferred embodiment, the setting upper and lower limit constraints are specifically as follows:

[0057] T min ≤T x ≤T max ;

[0058] Wherein, T min represents the lower limit of the operating time of the relay protection device; T x represents the operating time of the xth relay protection device; T max represents the upper limit of the operating time of the relay protection device.

[0059] For step S3, under the constraints of the above time coordination constraint and setting upper and lower limit constraints, the objective function is solved. The solution method can select algorithms such as particle swarm optimization algorithm, genetic algorithm or differential evolution algorithm for solution. Selecting the particle swarm optimization algorithm, under the constraints of the above constraints, using a set of operating times of each relay protection device and sensitivity coefficients of each relay protection device as the initial particles, and searching for the optimal solution through continuous iterative optimization. When the optimal solution is obtained, the operating times of each relay protection device and the sensitivity coefficients of each relay protection device when the sensitivity of each relay protection device in the new energy distribution network is maximized and the misoperation and refusal rate is minimized can be generated.

[0060] In a preferred embodiment, after generating the action time and sensitivity coefficient of each relay protection device in the new energy distribution network to maximize the sensitivity and minimize the misoperation and refusal rates of each relay protection device, the following steps are further included: obtaining the electrical parameters of the new energy distribution network at the current moment; wherein, the electrical parameters include: the load power demand at the current moment, the new energy output power at the current moment, the nodal admittance matrix, the equivalent impedance at the fault point, and the fault type at the fault point; the new energy output power includes the output power of wind power generation equipment and the output power of photovoltaic power generation equipment; the fault types include single-phase grounding, two-phase short circuit, and three-phase short circuit; calculating the voltage value of each node, the injected current of each node, the complex power between nodes, and the magnitude of the current flowing through the fault point when the fault occurs at the current moment according to the electrical parameters and the preset power grid power flow and short-circuit analysis model; if any one of the voltage value of each node, the injected current of each node, the complex power between nodes, and the magnitude of the current flowing through the fault point when the fault occurs at the current moment does not meet the preset threshold requirements, adjusting the weight coefficients of the objective function and re-solving the objective function; wherein, the weight coefficients include: the weight coefficient of the action time error term and the weight coefficient of the sensitivity reciprocal term.

[0061] Specifically, after obtaining the action time and sensitivity coefficient of each relay protection device in the new energy distribution network to maximize the sensitivity and minimize the misoperation and refusal rates of each relay protection device, it is necessary to verify the reliability of the action time and sensitivity coefficient of each relay protection device obtained by solving based on the above objective function (w1 and w2 under the initial value). This verification process needs to be realized based on a simulation platform. Build a simulation model of the new energy distribution network on the simulation platform, and set the action time and sensitivity coefficient of each relay protection device as the results obtained by solving the above objective function. After performing simulation operation on this simulation platform, then execute the following steps.

[0062] First, obtain the electrical parameters of the new energy distribution network at the moment corresponding to the action time and sensitivity coefficient of each relay protection device obtained, including the load power demand at the current moment, the new energy output power at the current moment, the nodal admittance matrix, the equivalent impedance at the fault point, and the fault type at the fault point; the new energy output power includes the output power of wind power generation equipment and the output power of photovoltaic power generation equipment; the fault types include single-phase grounding, two-phase short circuit, and three-phase short circuit.

[0063] It should be noted that when obtaining the nodal admittance matrix, it is necessary to obtain the topological structure data of the new energy distribution network. Through this topological structure data, the numbers and connection relationships of all nodes in the new energy distribution network, as well as the branch information of the direct connections between each node, are clarified. For each connecting branch, its complex impedance is obtained. For example, the complex impedance Z of the connecting branch between node i and node j ij . The admittance value of the shunt branch to the ground for each node is obtained. Usually, it is the admittance introduced by shunt elements such as shunt capacitors and reactances. For example, the admittance value Y of the shunt branch to the ground on node i sh,i . After obtaining the above data, by creating an initial n×n matrix, where n is the total number of nodes in the new energy distribution network. All elements in the initial matrix are set to 0. For each connecting branch, after calculating the mutual admittance and self-admittance, the calculated values are filled in, and the nodal admittance matrix can be obtained. The expression of the obtained nodal admittance matrix can be:

[0064]

[0065] Among them, Y ij represents the element value between node i and node j in the admittance matrix, with the unit of Siemens, representing the mutual admittance between two nodes (if i≠j) or the self-admittance of the node (if i = j); Z ij represents the complex impedance of the connecting branch between node i and node j, with the unit of ohm; i≠j indicates that the current element is the mutual admittance term between nodes; i = j indicates that the current element is the self-admittance term, used to represent the total admittance of node i; represents the sum of the admittances of all other nodes k connected to node i; Y sh,i represents the admittance value of the shunt branch to the ground on node i.

[0066] Preferably, the non-linear relationship between power and voltage is described by the power flow calculation formula to generate the nodal power equation, and the expression is:

[0067]

[0068] Among them, P i represents the active power injection of node i; Q i represents the reactive power injection of node i; n represents the total number of nodes in the network; V i represents the voltage amplitude of node i; V j represents the voltage amplitude of node j; G ij represents the real part (conductance) of the admittance between node i and node j, from the nodal admittance matrix; B ij represents the imaginary part (susceptance) of the admittance between node i and node j, from the nodal admittance matrix; θ ij represents the phase difference between the voltages of node i and node j; cosθ ij, sinθ ij The cosine and sine functions representing the phase difference are used to express the phasor relationship of power.

[0069] Using Ohm's law and the power definition formula, calculate the current at each node and the power flow in the branch. The expression is:

[0070]

[0071] Among them, I i represents the injected current at node i; V j represents the voltage at node j; Y ij represents the complex admittance between node i and node j; S ij represents the complex power from node i to node j; represents the conjugate complex number of the current from node i to node j.

[0072] Generate the total active power calculation expression according to the load power demand and the output power of new energy:

[0073] P total (t) = P load (t) + P RES (t);

[0074] Among them, P total (t) represents the total active power at time t; P load (t) represents the load power demand at time t; P RES (t) represents the output power of new energy at time t.

[0075] Construct an equivalent network model, set the short-circuit fault type and fault point, and calculate the short-circuit current. The expression is:

[0076]

[0077] Among them, I sc represents the magnitude of the current flowing through the fault point when the fault occurs; E represents the voltage of the equivalent power source at the fault point, usually in per-unit value; Z th represents the equivalent impedance looking into the system from the fault point; Z f represents the impedance of the ground or phase-to-phase fault at the fault point (such as the ground resistance, etc.).

[0078] Based on the above analysis, the preset power grid power flow and short-circuit analysis model can be obtained. Specifically:

[0079]

[0080] Among them, represents the preset power grid power flow and short-circuit analysis model; V(t) represents the voltage values of all nodes at time t; P load(t) represents the load power demand at time t; P RES (t) represents the new energy output power at time t; Y represents the nodal admittance matrix; f1(·) represents the power flow calculation function; I(t) represents the injection current of all nodes at time t; V i (t) represents the voltage value of node i at time t; represents the conjugate complex number of the current from node i to node j at time t; S ij (t) represents the complex power from node i to node j at time t; Z eq represents the equivalent impedance at the fault point; I sc (t) represents the magnitude of the current flowing through the fault point at the time of fault occurrence at time t; f2(·) represents the short-circuit current solving function.

[0081] Based on the above preset power grid power flow and short-circuit analysis model, the obtained electrical parameters are brought into the model to calculate the voltage values of each node, the injection currents of each node, the complex power between nodes, and the magnitude of the current flowing through the fault point at the time of fault occurrence at the current moment.

[0082] If any one of the voltage values of each node, the injection currents of each node, the complex power between nodes, and the magnitude of the current flowing through the fault point at the time of fault occurrence at the current moment does not meet the preset threshold requirements, then the weight coefficient of the action time error term of the objective function is first adjusted, and based on the adjusted objective function, recalculation is performed. After calculating the action time and sensitivity coefficient, the sensitivity coefficient is first judged against the sensitivity threshold. If it is greater than the sensitivity threshold, then simulation is carried out to judge the voltage values of each node, the injection currents of each node, the complex power between nodes, and the magnitude of the current flowing through the fault point at the time of fault occurrence at the current moment until it meets the requirements. If the judgment of the sensitivity coefficient against the sensitivity threshold fails, then the weight coefficient of the sensitivity reciprocal term is adjusted, and the steps of solving the objective function are returned to and executed again.

[0083] Through the above continuous adjustment of the weight coefficient of the objective function, and after judging and verifying the voltage values of each node, the injection currents of each node, the complex power between nodes, and the magnitude of the current flowing through the fault point at the time of fault occurrence at the current moment under the simulation based on the adjusted relay protection device, and after verifying the sensitivity coefficient, the action time of each relay protection device and the sensitivity coefficient of each relay protection device when each relay protection device in the new energy distribution network can be implemented, the sensitivity is maximized, and the misoperation and refusal rate is minimized can be obtained.

[0084] For step S4, when the sensitivity of each relay protection device in the new energy distribution network is maximized and the misoperation and refusal rate is minimized, the action time of each relay protection device and the sensitivity coefficient of each relay protection device are used to perform setting optimization on each relay protection device in the new energy distribution network.

[0085] Based on the above method embodiment, the present invention correspondingly provides a system embodiment.

[0086] As Figure 2 shown, an embodiment of the present invention provides a setting optimization system for a relay protection device of a new energy distribution network, including: a data acquisition module, a target function and constraint condition construction module, a target function solving module, and a setting optimization module;

[0087] The data acquisition module is used to acquire the basic data of the new energy distribution network; wherein, the basic data includes: the number of relay protection devices, the index of each relay protection device, the reference operation time of each relay protection device, the minimum operation time difference between upper and lower relay protection devices, the lower limit of the operation time of the relay protection device, and the upper limit of the operation time of the relay protection device;

[0088] The target function and constraint condition construction module is used to construct a target function for setting optimization of the relay protection device with the goal of maximizing the sensitivity of each relay protection device and minimizing the misoperation and refusal rate in the new energy distribution network according to the basic data; and construct the time coordination constraint and setting upper and lower limit constraints of the target function according to the basic data;

[0089] The target function solving module is used to solve the target function under the constraints of the time coordination constraint and the setting upper and lower limit constraints, and generate the operation time of each relay protection device and the sensitivity coefficient of each relay protection device when the sensitivity of each relay protection device in the new energy distribution network is maximized and the misoperation and refusal rate is minimized;

[0090] The setting optimization module is used to perform setting optimization on each relay protection device of the new energy distribution network with the operation time of each relay protection device and the sensitivity coefficient of each relay protection device when the sensitivity of each relay protection device in the new energy distribution network is maximized and the misoperation and refusal rate is minimized.

[0091] In a preferred embodiment, the target function is specifically:

[0092]

[0093] wherein, minA represents that the goal of the target function is to minimize the target function A; m represents the number of relay protection devices; x represents the index of the xth relay protection device; T ref,x represents the reference operation time of the xth relay protection device; T x represents the operation time of the xth relay protection device; S xIt represents the sensitivity coefficient of the xth relay protection device; w1 represents the weight coefficient of the action time error term; w2 represents the weight coefficient of the reciprocal of the sensitivity.

[0094] It should be noted that the system embodiments described above are merely illustrative. The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed to multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment. In addition, in the accompanying drawings of the system embodiments provided by the present invention, the connection relationship between modules indicates that they have a communication connection, which can be specifically implemented as one or more communication buses or signal lines. Those of ordinary skill in the art can understand and implement it without creative efforts.

[0095] Those skilled in the art can clearly understand that for the convenience and brevity, the specific working process of the device described above can refer to the corresponding process in the foregoing method embodiments, and will not be elaborated here.

[0096] Based on the foregoing method item embodiments, the present invention correspondingly provides terminal device item embodiments.

[0097] An embodiment of the present invention provides a terminal device, including a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor. When the processor executes the computer program, it implements a method for optimizing the setting of a relay protection device for a new energy distribution network according to any one of the present invention.

[0098] The terminal device can be a computing device such as a desktop computer, a notebook, a palm computer, and a cloud server. The terminal device may include, but is not limited to, a processor and a memory.

[0099] The so-called processor may be a central processing unit (CPU), or may also be other general-purpose processors, digital signal processors (DSPs), application specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc. The processor is the control center of the terminal device, and connects various parts of the entire terminal device through various interfaces and lines.

[0100] The memory can be used to store the computer program. By running or executing the computer program stored in the memory and invoking the data stored in the memory, the processor realizes various functions of the terminal device. The memory mainly includes a program storage area and a data storage area. Among them, the program storage area can store an operating system, application programs required for at least one function, etc.; the data storage area can store data created according to the use of the mobile phone, etc. In addition, the memory can include high-speed random access memory and can also include non-volatile memory, such as a hard disk, a memory, a plug-in hard disk, a Smart Media Card (SMC), a Secure Digital (SD) card, a Flash Card, at least one magnetic disk storage device, a flash memory device, or other volatile solid-state storage devices.

[0101] Based on the above method embodiment, the present invention correspondingly provides a storage medium embodiment.

[0102] An embodiment of the present invention provides a storage medium, which includes a stored computer program. When the computer program runs, it controls the device where the storage medium is located to execute a method for optimizing the setting of a relay protection device for a new energy distribution network according to any one of the present invention.

[0103] The storage medium is a computer-readable storage medium, and the computer program is stored in the computer-readable storage medium. When the computer program is executed by a processor, it can implement the steps of the above various method embodiments. Among them, the computer program includes computer program code, and the computer program code can be in the form of source code, object code, an executable file, or some intermediate form, etc. The computer-readable medium can include: any entity or device capable of carrying the computer program code, a recording medium, a USB flash drive, a mobile hard disk, a magnetic disk, an optical disc, a computer memory, a read-only memory (ROM), a random access memory (RAM), an electrical carrier signal, a telecommunication signal, and a software distribution medium, etc.

[0104] The above is the preferred embodiment of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements are also regarded as the protection scope of the present invention.

Claims

1. A method for optimizing the setting of a relay protection device for a new energy distribution network, characterized in that, Including: Obtain the basic data of the new energy distribution network; wherein, the basic data includes: the number of relay protection devices, the index of each relay protection device, the reference operating time of each relay protection device, the minimum operating time difference between the upper and lower level relay protection devices, the lower limit of the operating time of the relay protection device, and the upper limit of the operating time of the relay protection device; According to the basic data, with the goal of maximizing the sensitivity of each relay protection device in the new energy distribution network and minimizing the misoperation and refusal rate, construct the objective function for the setting optimization of the relay protection device; and construct the time coordination constraint and the setting upper and lower limit constraint of the objective function according to the basic data; Under the constraints of the time coordination constraint and the setting upper and lower limit constraint, solve the objective function to generate the operating time of each relay protection device and the sensitivity coefficient of each relay protection device when the sensitivity of each relay protection device in the new energy distribution network is maximized and the misoperation and refusal rate is minimized; Use the operating time of each relay protection device and the sensitivity coefficient of each relay protection device when the sensitivity of each relay protection device in the new energy distribution network is maximized and the misoperation and refusal rate is minimized to perform setting optimization on each relay protection device in the new energy distribution network.

2. The relay protection device setting optimization method for a new energy distribution network according to claim 1, characterized in that The objective function is specifically: Among them, minA indicates that the objective of the objective function is to minimize objective function A; m represents the number of relay protection devices; x represents the index of the x-th relay protection device; T ref,x represents the reference operating time of the x-th relay protection device; T x represents the operating time of the x-th relay protection device; S x represents the sensitivity coefficient of the x-th relay protection device; w1 represents the weight coefficient of the operating time error term; w2 represents the weight coefficient of the reciprocal of the sensitivity.

3. The relay protection device setting optimization method for a new energy distribution network according to claim 2, wherein, The time coordination constraint is specifically: T x+1 -T x ≥ΔT min ; Among them, T x represents the operating time of the x-th relay protection device; T x+1 represents the operating time of the (x + 1)-th relay protection device, and T x+1 is the superior relay protection device of T x ; ΔT min represents the minimum operating time difference between the superior and inferior relay protection devices.

4. The relay protection device setting optimization method for a new energy distribution network according to claim 3, characterized in that, The setting upper and lower limit constraint is specifically: T min ≤T x ≤T max ; Among them, T min represents the lower limit of the operating time of the relay protection device; T x represents the operating time of the x-th relay protection device; T max represents the upper limit of the operating time of the relay protection device.

5. The relay protection device setting optimization method for a new energy distribution network according to claim 4, characterized in that, After generating the operating time of each relay protection device and the sensitivity coefficient of each relay protection device when the sensitivity of each relay protection device in the new energy distribution network is maximized and the misoperation and refusal rate is minimized, it further includes: Obtain the electrical parameters of the new energy distribution network at the current moment; wherein, the electrical parameters include: the load power demand at the current moment, the new energy output power at the current moment, the nodal admittance matrix, the equivalent impedance at the fault point, and the fault type at the fault point; the new energy output power includes the output power of wind power generation equipment and the output power of photovoltaic power generation equipment; the fault type includes single-phase grounding, two-phase short circuit, and three-phase short circuit; According to the electrical parameters and the preset power flow and short-circuit analysis model of the power grid, calculate the voltage value of each node, the injected current of each node, the complex power between nodes, and the magnitude of the current flowing through the fault point when a fault occurs at the current moment; If any one of the voltage value of each node, the injected current of each node, the complex power between nodes, and the magnitude of the current flowing through the fault point when a fault occurs at the current moment does not meet the preset threshold requirements, adjust the weight coefficients of the objective function and re-solve the objective function; wherein, the weight coefficients include: the weight coefficient of the action time error term and the weight coefficient of the sensitivity reciprocal term.

6. The setting optimization method of a relay protection device for a new energy distribution network according to claim 5, characterized in that, The preset power flow and short-circuit analysis model of the power grid is specifically: Among them, represents a preset power grid power flow and short-circuit analysis model; V(t) represents the voltage values of all nodes at time t; P load (t) represents the load power demand at time t; P RES (t) represents the output power of new energy at time t; Y represents the nodal admittance matrix; f1(·) represents the power flow calculation function; I(t) represents the injection current of all nodes at time t; V i (t) represents the voltage value of node i at time t; represents the conjugate complex number of the current from node i to node j at time t; S ij (t) represents the complex power from node i to node j at time t; Z eq represents the equivalent impedance at the fault point; I sc (t) represents the magnitude of the current flowing through the fault point at the time of fault occurrence at time t; f2(·) represents the short-circuit current solving function.

7. A relay protection device setting optimization system for a new energy distribution network, characterized in that, Including: A data acquisition module, an objective function and constraint condition construction module, an objective function solving module, and a setting optimization module; The data acquisition module is used to acquire the basic data of the new energy distribution network; wherein, the basic data includes: the number of relay protection devices, the index of each relay protection device, the reference operating time of each relay protection device, the minimum operating time difference between upper and lower level relay protection devices, the lower limit of the operating time of the relay protection device, and the upper limit of the operating time of the relay protection device; The objective function and constraint condition construction module is used to construct the objective function for the setting optimization of the relay protection device with the goal of maximizing the sensitivity and minimizing the misoperation and refusal rate of each relay protection device in the new energy distribution network according to the basic data; and construct the time coordination constraint and setting upper and lower limit constraint of the objective function according to the basic data; The objective function solving module is used to solve the objective function under the constraints of the time coordination constraint and the setting upper and lower limit constraint, and generate the operating time of each relay protection device and the sensitivity coefficient of each relay protection device when the sensitivity of each relay protection device in the new energy distribution network is maximized and the misoperation and refusal rate is minimized; The setting optimization module is used to perform setting optimization on each relay protection device of the new energy distribution network with the operating time of each relay protection device and the sensitivity coefficient of each relay protection device when the sensitivity of each relay protection device in the new energy distribution network is maximized and the misoperation and refusal rate is minimized; 8. The setting optimization system for the relay protection device of a new energy distribution network according to claim 7, wherein, The objective function is specifically: Among them, minA indicates that the objective of the objective function is to minimize objective function A; m represents the number of relay protection devices; x represents the index of the x-th relay protection device; T ref,x represents the reference operating time of the x-th relay protection device; T x represents the operating time of the x-th relay protection device; S x represents the sensitivity coefficient of the x-th relay protection device; w1 represents the weight coefficient of the operating time error term; w2 represents the weight coefficient of the reciprocal of the sensitivity.

9. A terminal device, characterized in that, It includes a processor, a memory, and a computer program stored in the memory and configured to be executed by the processor. When the processor executes the computer program, it implements a method for setting optimization of relay protection devices in a new energy distribution network according to any one of claims 1 to 6.

10. A storage medium, characterized in that, The storage medium includes a stored computer program. When the computer program runs, it controls the device where the storage medium is located to execute a method for setting optimization of relay protection devices in a new energy distribution network according to any one of claims 1 to 6.

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