Voltage and harmonic collaborative treatment method, device, equipment and storage medium

Abstract

The invention relates to the technical field of active power distribution network electric energy quality treatment, in particular to a voltage and harmonic collaborative treatment method and device, electronic equipment and a storage medium. According to the implementation mode of the voltage and harmonic collaborative treatment method, the influence of reactive voltage sensitivity on the voltage of each distributed power supply access node is analyzed; the output of the distributed power supply is adjusted by mainly adjusting reactive power and reducing active power output as an auxiliary, and when the active power output is reduced, the reduced active power is stored through an energy storage device, that is, the maximum consumption of power generation of the distributed power supply is realized by adjusting the electric energy quality, and the energy utilization rate is improved; in addition, according to the embodiment of the invention, the residual capacity of the distributed power supply and the energy storage device is utilized to treat voltage and harmonic waves, so that the investment of electric energy treatment equipment resources is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of power quality management of active distribution networks, and in particular to a voltage and harmonic coordinated management method, device, electronic equipment and storage medium. Background Art

[0002] In order to help achieve the goals of "carbon peak" and "carbon neutrality", distributed photovoltaics have ushered in a blowout development in recent years, and the scale of grid connection has continued to expand. At the same time, the access of distributed photovoltaics with high penetration has also brought new challenges to the operation and control of the power system, turning the distribution network from a passive network into an active network, and power reverse transmission often occurs. Too much access capacity will lead to the risk of overvoltage. The reverse flow and intermittent voltage increase caused by distributed photovoltaic power are the main limiting factors for the integration of photovoltaic power generation in low-voltage distribution networks.

[0003] At present, the voltage over-limit and harmonic excess problems caused by the connection of distributed photovoltaics to the distribution network are mainly solved by limiting the output of photovoltaics. As a result, the consumption rate of green energy such as photovoltaics is greatly reduced, and the management of the voltage over-limit and harmonic excess problems has not been greatly improved.

[0004] Based on this, it is necessary to develop and design a method for coordinated management of voltage and harmonics. Summary of the invention

[0005] The embodiments of the present invention provide a method, device, electronic device and storage medium for coordinated control of voltage and harmonics, which are used to solve the problem in the prior art that the photovoltaic absorption rate decreases due to the control of power quality.

[0006] In a first aspect, an embodiment of the present invention provides a voltage and harmonic coordinated control method, comprising:

[0007] Acquire multiple reactive voltage sensitivities, wherein each reactive voltage sensitivity corresponds to an access node of a distributed power source, and the reactive voltage sensitivity represents the influence of reactive power on node voltage;

[0008] Analyze the voltage over-limit and harmonic over-limit conditions of each access node respectively;

[0009] For access nodes with voltage exceeding the limit, the active and reactive outputs of the distributed power sources and the energy storage system are adjusted according to the voltage exceeding the limit, power factor, corresponding reactive voltage sensitivity, remaining capacity of the distributed power sources and capacity of the energy storage system, so as to manage the access nodes with voltage exceeding the limit;

[0010] After completing the voltage over-limit control, for the access nodes with excessive harmonics, the harmonic control requirements are determined based on the harmonic exceeding conditions of the access nodes, and the harmonic output of the distributed power sources and the energy storage system are adjusted based on the remaining capacity of the distributed power sources at the access nodes and the remaining capacity of the energy storage system.

[0011] In a possible implementation manner, the obtaining of multiple reactive voltage sensitivities includes:

[0012] The multiple reactive voltage sensitivities are determined according to a first formula, a transformer outlet voltage value, and a line impedance value between an access node and a transformer node, wherein the first formula is:

[0013]

[0014] In the formula, S Ui is the reactive voltage sensitivity, V s is the transformer outlet voltage, X i Represents the line impedance value between the i-th access node and the transformer node.

[0015] In a possible implementation manner, the respectively analyzing the harmonic exceeding standard condition of each access node includes:

[0016] The voltage total harmonic distortion rate of each access node is determined according to the second formula, the effective value of the fundamental voltage of the access point, and the root mean square values ​​of multiple harmonic voltages, wherein the second formula is:

[0017]

[0018] Where, THD U,i (t) is the total harmonic distortion rate of the voltage at access node i at time t, U h,i (t) is the root mean square value of the harmonic voltage of the access node i at time t, U 1,i (t) is the effective value of the fundamental voltage of access node i at time t, and H is the maximum harmonic order.

[0019] In a possible implementation, for the access node with voltage exceeding the limit, the active output and reactive output of the distributed power source and the energy storage system are adjusted according to the voltage exceeding the limit, the power factor, the corresponding reactive voltage sensitivity, the remaining capacity of the distributed power source and the capacity of the energy storage system of the access node, so as to manage the access node with voltage exceeding the limit, including:

[0020] Determine the remaining capacity of the distributed generation at the over-limit access node;

[0021] Determine the reactive power compensation amount based on the voltage over-limit situation of the access node, the corresponding reactive power voltage sensitivity and the remaining capacity of the distributed power source;

[0022] If the voltage exceeds the upper limit and the power factor of the access node is less than the target power factor, the reactive output of the distributed power source is adjusted according to the reactive compensation amount;

[0023] If the voltage exceeds the upper limit and the power factor of the access node is greater than the target power factor, the active output of the distributed power source connected to the grid is reduced, and the reduced active output is used to store energy in the energy storage system. When the reduced active output of the distributed power source reaches the upper limit and the voltage still exceeds the upper limit, the reactive output of the distributed power source is adjusted;

[0024] If the voltage exceeds the upper limit and the power factor of the access node is equal to the target power factor, the reactive output of the energy storage system is adjusted;

[0025] If the voltage exceeds the lower limit, the active or reactive output of the energy storage system is adjusted according to the remaining energy of the energy storage system.

[0026] In a possible implementation, determining the reactive compensation amount of the distributed power source according to the voltage over-limit condition of the access node, the corresponding reactive voltage sensitivity, and the remaining capacity of the distributed power source includes:

[0027] The reactive compensation amount of the distributed power source is determined according to the third formula, the voltage over-limit condition of the access node, the corresponding reactive voltage sensitivity, and the remaining capacity of the distributed power source, wherein the third formula is:

[0028]

[0029] In the formula, Q PV1 is the reactive power compensation of distributed power source, V low 、V lb 、V ub 、V up They are the lower voltage limit for equipment operation, the lower voltage limit for safe operation of the distribution network, the upper voltage limit for equipment operation, and the upper voltage limit for safe operation of the distribution network. max is the maximum adjustable reactive capacity of the distributed generation at the corresponding node, ρ min is the minimum power factor of distributed power supply, S re is the remaining capacity of distributed generation, S inv is the capacity of distributed generation, S Ui is the reactive voltage sensitivity, M is a constant greater than zero, V PCC is the voltage at the access point, P pv It is the active power of distributed power source;

[0030] The reducing the active output of the distributed power source connected to the grid includes:

[0031] The active power adjustment step length is determined according to the fourth formula, and the fourth formula is:

[0032]

[0033] Where ΔP pv is the active power adjustment step size, P rated is the rated active power, X is the adjustment ratio, ΔP max is the maximum active power adjustment step, Q pv is the reactive power of distributed generation, ρ min is the lower limit of power factor;

[0034] Reducing the active power output of the distributed power source connected to the grid according to the active power adjustment step size;

[0035] If the voltage does not reach the safety level, the process jumps to the step of determining the active power adjustment step size according to the fourth formula.

[0036] In a possible implementation, adjusting the reactive output of the energy storage system includes:

[0037] The reactive output compensation amount of the energy storage system is determined according to the fifth formula, wherein the fifth formula is:

[0038]

[0039] Where V low 、V lb 、V ub 、V up They are the lower voltage limit for equipment operation, the lower voltage limit for safe operation of the distribution network, the upper voltage limit for equipment operation, and the upper voltage limit for safe operation of the distribution network. ESS is the rated capacity of the energy storage system, Q ESS is the reactive output compensation of the energy storage system, X i represents the line impedance value between the i-th access node and the transformer node;

[0040] Adjust the reactive output of the energy storage system according to the reactive output compensation amount of the energy storage system;

[0041] When the voltage exceeds the lower limit, the active or reactive output of the energy storage system is adjusted according to the residual energy of the energy storage system, including:

[0042] If the remaining energy of the energy storage system is greater than zero, discharge is performed according to the remaining energy of the energy device;

[0043] Otherwise, the reactive output compensation amount of the energy storage system is determined according to the fifth formula, and the reactive output of the energy storage system is adjusted according to the reactive output compensation amount of the energy storage system.

[0044] In a possible implementation, determining the harmonic control demand according to the harmonic exceeding standard of the access node, and adjusting the harmonic output of the distributed power source and the energy storage system according to the remaining capacity of the access node and the remaining capacity of the energy storage system, includes:

[0045] The harmonic control requirement is determined according to the sixth formula, wherein the sixth formula is:

[0046]

[0047] Where U 1,PV is the effective value of the fundamental voltage at the grid-connected point at that moment, n is the maximum harmonic order that the inverter can control, I k is the hth harmonic current of the access node;

[0048] The remaining capacity of the distributed power source and the remaining capacity of the energy storage device are determined according to the seventh formula, wherein the seventh formula is:

[0049]

[0050] In the formula, S re is the remaining capacity of distributed generation, S ESS is the remaining capacity of the energy storage device, P pv is the active power output of the distributed power source, Q pv is the reactive power output of distributed generation, S inv is the capacity of the inverter, P ESS is the charging and discharging power of the energy storage device, Q pv is the reactive output of the energy storage device, S ESS is the capacity of the energy storage device;

[0051] According to the harmonic control demand, the remaining capacity of the distributed power source and the remaining capacity of the energy storage device, the harmonic current with the same amplitude and opposite phase as the harmonic current is preferentially output from the distributed power source. When the remaining capacity of the distributed power source is exhausted, the harmonic current with the same amplitude and opposite phase as the harmonic current is output from the energy storage device.

[0052] In a second aspect, an embodiment of the present invention provides a voltage and harmonic coordinated governance device, which is used to implement the voltage and harmonic coordinated governance method described in the first aspect or any possible implementation of the first aspect, and the voltage and harmonic coordinated governance device includes:

[0053] A voltage reactive power sensitivity determination module is used to obtain multiple reactive voltage sensitivities, wherein each reactive voltage sensitivity corresponds to an access node of a distributed power source, and the reactive voltage sensitivity represents the influence of reactive power on the node voltage;

[0054] The voltage and harmonic excess calculation module is used to analyze the voltage over-limit situation and harmonic excess situation of each access node respectively;

[0055] The voltage over-limit management module is used to adjust the active and reactive outputs of the distributed power supply and the energy storage system according to the voltage over-limit situation, power factor, corresponding reactive voltage sensitivity, remaining capacity of the distributed power supply and capacity of the energy storage system of the access node where the voltage is over-limited, so as to manage the access node where the voltage is over-limited;

[0056] as well as,

[0057] The harmonic excess control module is used to determine the harmonic control requirements for access nodes with excessive harmonics after completing voltage over-limit control, based on the harmonic excess situation of the access nodes, and adjust the harmonic output of the distributed power supply and the energy storage system based on the remaining capacity of the access nodes and the remaining capacity of the energy storage system.

[0058] In a third aspect, an embodiment of the present invention provides an electronic device, comprising a memory and a processor, wherein the memory stores a computer program that can be run on the processor, and when the processor executes the computer program, it implements the steps of the method described in the first aspect or any possible implementation method of the first aspect.

[0059] In a fourth aspect, an embodiment of the present invention provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the method described in the first aspect or any possible implementation of the first aspect are implemented.

[0060] Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

[0061] The implementation method of the voltage and harmonic coordinated control method of the present invention first obtains multiple reactive voltage sensitivities, wherein each reactive voltage sensitivity corresponds to an access node of a distributed power source, and the reactive voltage sensitivity characterizes the influence of reactive power on the node voltage; then the voltage over-limit situation and the harmonic over-standard situation of each access node are analyzed respectively; then for the access nodes with voltage over-limit, according to the voltage over-limit situation, power factor, corresponding reactive voltage sensitivity, remaining capacity of the distributed power source and capacity of the energy storage system of the access node, the active output and reactive output of the distributed power source and the energy storage system are adjusted to control the access nodes with voltage over-limit; finally, after completing the voltage over-limit control, for the access nodes with harmonic over-standard, the harmonic control demand is determined according to the harmonic over-standard situation of the access nodes, and the harmonic output of the distributed power source and the energy storage system is adjusted according to the remaining capacity of the access node and the remaining capacity of the energy storage system. The implementation mode of the present invention analyzes the influence of reactive voltage sensitivity on the voltage of each distributed power supply access node, adjusts the output of the distributed power supply mainly by adjusting reactive power and supplemented by reducing active power output, and when reducing active output, stores the reduced active power through an energy storage device, that is, adjusts the power quality to maximize the consumption of distributed power generation, thereby improving energy utilization; and the implementation mode of the present invention also utilizes the remaining capacity of the distributed power supply and the energy storage device to manage voltage and harmonics, thereby reducing the investment in power management equipment resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0063] Figure 1 It is a flow chart of the voltage and harmonic coordinated control method provided by an embodiment of the present invention;

[0064] Figure 2 It is a flow chart of voltage harmonic control provided by an embodiment of the present invention;

[0065] Figure 3 is a reactive voltage control curve diagram of an embodiment of the present invention;

[0066] Figure 4 It is a functional block diagram of a voltage and harmonic coordinated control device provided in an embodiment of the present invention;

[0067] Figure 5 It is a functional block diagram of an electronic device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0068] In the following description, specific details such as specific system structures and technologies are provided for the purpose of illustration rather than limitation so as to provide a thorough understanding of the embodiments of the present invention. However, it should be clear to those skilled in the art that the present invention may be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, and methods are omitted so as not to obscure the description of the present invention with unnecessary details.

[0069] In order to make the purpose, technical solutions and advantages of the present invention more clear, a specific implementation method will be described below in conjunction with the accompanying drawings.

[0070] The following is a detailed description of an embodiment of the present invention. This example is implemented on the premise of the technical solution of the present invention, and a detailed implementation method and a specific operation process are given, but the protection scope of the present invention is not limited to the following embodiments.

[0071] Figure 1 A flowchart of a method for coordinated control of voltage and harmonics provided in an embodiment of the present invention.

[0072] like Figure 1 As shown, it shows a flowchart of the voltage and harmonic coordinated control method provided by an embodiment of the present invention, which is described in detail as follows:

[0073] In step 101, a plurality of reactive voltage sensitivities are obtained, wherein each reactive voltage sensitivity corresponds to an access node of a distributed power source, and the reactive voltage sensitivity represents the influence of reactive power on node voltage.

[0074] In some implementations, obtaining a plurality of reactive voltage sensitivities includes:

[0075] The multiple reactive voltage sensitivities are determined according to a first formula, a transformer outlet voltage value, and a line impedance value between an access node and a transformer node, wherein the first formula is:

[0076]

[0077] In the formula, S Ui is the reactive voltage sensitivity, V s is the transformer outlet voltage, X i Represents the line impedance value between the i-th access node and the transformer node.

[0078] For example, Figure 2-3 As shown, the embodiment of the present invention first determines the approximate reactive voltage sensitivity, and one determination method is to determine it according to the first formula:

[0079]

[0080] In the formula, S Ui is the reactive voltage sensitivity, V s is the transformer outlet voltage, X i It represents the line impedance between the i-th access node and the transformer node, which can be calculated by line length × impedance per unit length.

[0081] In addition, in some scenarios, it is also necessary to calculate the slope k of the reactive voltage control curve of each device. In order to make different devices participate in the reactive power regulation of the system as much as possible in the same state, different reactive voltage control curves are configured for the inverter controller according to the local reactive voltage sensitivity of each node, so that the slope of the curve satisfies the formula:

[0082] k1S Q1 =k2S Q2 =k n S Qn =M

[0083] In the formula, k n is the slope of the reactive voltage control curve of the inverter at the nth node, M is a constant, and different M values ​​will produce different control effects. It is necessary to select a suitable M value according to the actual system. The larger the M value is, the greater the degree to which the nodes near the transformer side participate in reactive regulation. However, an excessively large M value will cause the system voltage to be regulated too frequently, affecting the service life of the controller. The initial value of M in the implementation mode of the present invention is 1.42.

[0084] In step 102, the voltage exceeding limit and the harmonic exceeding limit of each access node are analyzed respectively.

[0085] In some implementations, the respectively analyzing the harmonic exceeding condition of each access node includes:

[0086] The voltage total harmonic distortion rate of each access node is determined according to the second formula, the effective value of the fundamental voltage of the access point, and the root mean square values ​​of multiple harmonic voltages, wherein the second formula is:

[0087]

[0088] Where, THD U,i (t) is the total harmonic distortion rate of the voltage at access node i at time t, U h,i (t) is the root mean square value of the harmonic voltage of the access node i at time t, U 1,i (t) is the effective value of the fundamental voltage of access node i at time t, and H is the maximum harmonic order.

[0089] Exemplarily, first determine whether the current voltage monitoring value Vpcc of the distributed power supply device access node i exceeds the action limit:

[0090] Get the effective value of fundamental voltage monitoring to set the upper and lower limits of voltage for safe operation and the upper and lower limits of voltage for equipment action. (The upper and lower limits of voltage for safe operation are 1.07pu and 0.93pu, and the upper and lower limits of voltage for equipment action are 1.06pu and 0.94pu)

[0091] Then determine whether the voltage total harmonic distortion rate exceeds the standard:

[0092]

[0093] Where, THD U,i (t) is the total harmonic distortion rate of the voltage at node i at time t, U ,i (t) is the root mean square value of the hth harmonic voltage at node ii at time t, U 1,i (t) is the effective value of the fundamental voltage at node i at time t.

[0094] In the implementation manner of the present invention, if neither exceeds the standard, no action is taken; if only the voltage exceeds the limit, step 103 is performed; if only the harmonic exceeds the standard, step 104 is performed; if both the voltage and the harmonic exceed the standard, the voltage is controlled first, step 103 is performed first, and then step 104 is performed.

[0095] In step 103, for access nodes with voltage exceeding the limit, the active output and reactive output of the distributed power source and the energy storage system are adjusted according to the voltage exceeding the limit, power factor, corresponding reactive voltage sensitivity, remaining capacity of the distributed power source and capacity of the energy storage system of the access node to manage the access node with voltage exceeding the limit.

[0096] In some implementations, for an access node with voltage exceeding the limit, adjusting the active output and reactive output of the distributed power source and the energy storage system according to the voltage exceeding the limit, power factor, corresponding reactive voltage sensitivity, remaining capacity of the distributed power source, and capacity of the energy storage system of the access node to manage the access node with voltage exceeding the limit, including:

[0097] Determine the remaining capacity of the distributed generation at the over-limit access node;

[0098] Determine the reactive power compensation amount based on the voltage over-limit situation of the access node, the corresponding reactive power voltage sensitivity and the remaining capacity of the distributed power source;

[0099] If the voltage exceeds the upper limit and the power factor of the access node is less than the target power factor, the reactive output of the distributed power source is adjusted according to the reactive compensation amount;

[0100] If the voltage exceeds the upper limit and the power factor of the access node is greater than the target power factor, the active output of the distributed power source connected to the grid is reduced, and the reduced active output is used to store energy in the energy storage system. When the reduced active output of the distributed power source reaches the upper limit and the voltage still exceeds the upper limit, the reactive output of the distributed power source is adjusted;

[0101] If the voltage exceeds the upper limit and the power factor of the access node is equal to the target power factor, the reactive output of the energy storage system is adjusted;

[0102] If the voltage exceeds the lower limit, the active or reactive output of the energy storage system is adjusted according to the remaining energy of the energy storage system.

[0103] In some implementations, determining the reactive compensation amount of the distributed power source according to the voltage over-limit condition of the access node, the corresponding reactive voltage sensitivity, and the remaining capacity of the distributed power source includes:

[0104] The reactive compensation amount of the distributed power source is determined according to the third formula, the voltage over-limit condition of the access node, the corresponding reactive voltage sensitivity, and the remaining capacity of the distributed power source, wherein the third formula is:

[0105]

[0106] In the formula, Q PV1 is the reactive power compensation of distributed generation, B low , B lb , B ub , B up They are the lower voltage limit for equipment operation, the lower voltage limit for safe operation of the distribution network, the upper voltage limit for equipment operation, and the upper voltage limit for safe operation of the distribution network. max is the maximum adjustable reactive capacity of the photovoltaic inverter at the corresponding node, ρ min is the minimum power factor of the photovoltaic inverter, S re is the remaining capacity of the inverter, S inv is the capacity of the inverter, S Ui is the reactive voltage sensitivity, M is a constant greater than zero, V PCC is the voltage at the access point, P pv It is photovoltaic active;

[0107] The reducing the active output of the distributed power source connected to the grid includes:

[0108] The active power adjustment step length is determined according to the fourth formula, and the fourth formula is:

[0109]

[0110] Where ΔP pv is the active power adjustment step size, P ratedis the rated active power, X is the adjustment ratio, ΔP max is the maximum active power adjustment step, Q pv is the photovoltaic reactive power, ρ min is the lower limit of power factor;

[0111] Reducing the active power output of the distributed power source connected to the grid according to the active power adjustment step size;

[0112] If the voltage does not reach the safety level, the process jumps to the step of determining the active power adjustment step size according to the fourth formula.

[0113] In some embodiments, adjusting the reactive output of the energy storage system includes:

[0114] The reactive output compensation amount of the energy storage system is determined according to the fifth formula, wherein the fifth formula is:

[0115]

[0116] Where V low 、V lb , B ub , B up They are the lower voltage limit for equipment operation, the lower voltage limit for safe operation of the distribution network, the upper voltage limit for equipment operation, and the upper voltage limit for safe operation of the distribution network. ESS is the rated capacity of the energy storage system, Q ESS is the reactive output compensation of the energy storage system, X i represents the line impedance value between the i-th access node and the transformer node;

[0117] Adjust the reactive output of the energy storage system according to the reactive output compensation amount of the energy storage system;

[0118] When the voltage exceeds the lower limit, the active or reactive output of the energy storage system is adjusted according to the residual energy of the energy storage system, including:

[0119] If the remaining energy of the energy storage system is greater than zero, discharge is performed according to the remaining energy of the energy device;

[0120] Otherwise, the reactive output compensation amount of the energy storage system is determined according to the fifth formula, and the reactive output of the energy storage system is adjusted according to the reactive output compensation amount of the energy storage system.

[0121] Exemplarily, in terms of voltage over-limit management, the embodiment of the present invention is carried out through the following subdivided steps (taking photovoltaic power generation as an example):

[0122] (1) Calculate the remaining capacity S of the distributed power source (such as photovoltaic inverter) at the out-of-limit node re

[0123]

[0124] Where P pv is the active power output of distributed power generation, S inv is the capacity of distributed power generation.

[0125] If the remaining capacity is not 0, then go to step (2) to perform reactive power control of the distributed generation; if the remaining capacity is 0, then go to step (3).

[0126] (2) Reactive power control of distributed power generation

[0127] Calculate reactive power compensation Q PV1 :

[0128]

[0129] In the formula, Q PV1 is the reactive power compensation of distributed power source, V low 、V lb 、V ub 、V up They are the lower voltage limit for equipment operation, the lower voltage limit for safe operation of the distribution network, the upper voltage limit for equipment operation, and the upper voltage limit for safe operation of the distribution network. max is the maximum adjustable reactive capacity of the distributed generation at the corresponding node, ρ min is the minimum power factor of distributed power supply, S re is the remaining capacity of distributed generation, S inv is the capacity of distributed generation, S Ui is the reactive voltage sensitivity, M is a constant greater than zero, V PCC is the voltage at the access point, P pv It is the active power of distributed power source.

[0130] The voltage regulation-free region is [V lb , V ub ]; Comprehensively consider the capacity constraints and power factor constraints of distributed power sources (photovoltaic inverters), Q max is the maximum adjustable reactive capacity of the distributed generation at the corresponding node, ρ min is the minimum power factor of distributed power supply, S re is the remaining capacity of distributed generation, S inv is the capacity of the distributed power source. Set the minimum power factor of the distributed power source ρ min , can be set to 0.95; the nighttime reactive power adjustable coefficient can be set to 1.

[0131] (3) Determine the voltage over-limit type

[0132] If the voltage is above the upper limit, >1.07pu, go to (4); if the voltage is below the lower limit, <0.93pu, go to (5);

[0133] (4) If the voltage exceeds the upper limit

[0134] If the current power factor ρ>ρ min , first ensure the power factor of the distributed power source, then maintain the current distributed power source reactive power Q pv unchanged, with rated active power P rated The active power reduction ΔP is carried out in steps of X% pv , which can be set to 5%:

[0135]

[0136] Where ΔP pv is the active power adjustment step size, P rated is the rated active power, X is the adjustment ratio, ΔP max is the maximum active power adjustment step, Q pv is the reactive power of distributed generation, ρ min It is the lower limit of power factor.

[0137] Monitor the voltage at the end of each reduction. If the voltage reaches a safe level, stop. If the voltage still exceeds the limit, continue to reduce until ΔP is reached. max . Using the reduced active power ΔP pv Charge the energy storage. If it is reduced to ΔP max If the voltage still exceeds the upper limit, the capacity ΔS released by the inverter is used. re To perform local reactive power regulation:

[0138]

[0139] Where P pv is the active output value of the distributed generation at the current moment, S inv is the rated capacity of the inverter.

[0140] If the current power factor ρ = ρ min , then the energy storage system reactive power control is performed. Calculate the reactive power compensation Q ESS :

[0141]

[0142] Where V low 、V lb 、V ub 、V up There are four voltage action thresholds configured for the control strategy, among which V pcc is the voltage monitoring effective value, V up 、V low The upper and lower limits of voltage for safe operation of the distribution network; V ub 、V lbThe voltage upper and lower limits of the device are set, and the voltage adjustment-free area is [V low , V up ]; S ESS is the rated capacity of the energy storage system.

[0143] (5) If the voltage exceeds the lower limit (the energy storage device takes the energy storage battery as an example)

[0144] Check whether the remaining energy of the energy storage battery is > 0. If the remaining energy of the energy storage battery P ESS >0, then according to P ESS Discharge, if the remaining energy of the energy storage battery is P ESS =0, then the energy storage system will be reactively controlled:

[0145] Calculate reactive power compensation Q ESS :

[0146]

[0147] Where V low 、V lb 、V ub 、V up They are the lower voltage limit for equipment operation, the lower voltage limit for safe operation of the distribution network, the upper voltage limit for equipment operation, and the upper voltage limit for safe operation of the distribution network. ESS is the rated capacity of the energy storage system, Q ESS is the reactive output compensation of the energy storage system, X i Represents the line impedance value between the i-th access node and the transformer node.

[0148] In step 104, after completing the voltage over-limit control, for the access node with excessive harmonics, the harmonic control demand is determined according to the excessive harmonics of the access node, and the harmonic output of the distributed power source and the energy storage system is adjusted according to the remaining capacity of the access node and the remaining capacity of the energy storage system.

[0149] In some embodiments, determining the harmonic control demand according to the harmonic exceeding standard of the access node, and adjusting the harmonic output of the distributed power source and the energy storage system according to the remaining capacity of the access node and the remaining capacity of the energy storage system, includes:

[0150] The harmonic control requirement is determined according to the sixth formula, wherein the sixth formula is:

[0151]

[0152] Where U 1,PV is the effective value of the fundamental voltage at the grid-connected point at that moment, n is the maximum harmonic order that the inverter can control, I k is the hth harmonic current of the access node;

[0153] The remaining capacity of the distributed power source and the remaining capacity of the energy storage device are determined according to the seventh formula, wherein the seventh formula is:

[0154]

[0155] In the formula, S re is the remaining capacity of distributed generation, S ESS is the remaining capacity of the energy storage device, P pv is the active power output of the distributed power source, Q pv is the reactive power output of distributed generation, S inv is the capacity of the inverter, P ESS is the charging and discharging power of the energy storage device, Q pv is the reactive output of the energy storage device, S ESS is the capacity of the energy storage device;

[0156] According to the harmonic control demand, the remaining capacity of the distributed power source and the remaining capacity of the energy storage device, the harmonic current with the same amplitude and opposite phase as the harmonic current is preferentially output from the distributed power source. When the remaining capacity of the distributed power source is exhausted, the harmonic current with the same amplitude and opposite phase as the harmonic current is output from the energy storage device.

[0157] Exemplarily, in terms of harmonic excess control, the embodiment of the present invention is implemented through the following subdivided steps (the distributed power source takes a photovoltaic inverter as an example, and the energy storage device takes an energy storage battery as an example):

[0158] (1) Calculate harmonic control requirements

[0159] Determine the number of harmonics exceeding the standard k. Get the harmonic current value I monitored at the current moment k .

[0160] According to the number of harmonic currents exceeding the standard, the phase Y of the harmonic current exceeding the standard is obtained.

[0161] Calculate the power demand at this moment:

[0162]

[0163] Where U 1,PV is the effective value of the fundamental voltage at the grid-connected point at that moment, n is the maximum harmonic order that the inverter can control, I k is the hth harmonic current of the access node; the maximum harmonic order that the inverter can control, its value is determined by the control capability of the inverter, and can currently be set to 19.

[0164] (2) Calculate the remaining capacity of the solar-storage inverter and the remaining capacity of the energy storage battery

[0165] Calculate the remaining capacity S of the photovoltaic inverter at the node at the current moment re

[0166]

[0167] Where P pv is the photovoltaic active power at the current moment; Q pv is the photovoltaic reactive power at the current moment; S inv is the capacity of the inverter. Calculate the remaining capacity S of the energy storage system at the node at the current moment ess

[0168]

[0169] Where P ESS Q is the energy storage charging and discharging power at the current moment; pv is the reactive power output of the energy storage system at the current moment; S ESS S ESS is the capacity of the energy storage system. If the remaining capacity of the photovoltaic inverter is not 0, go to (3). Otherwise, go to step (4).

[0170] (3) Harmonic suppression of photovoltaic inverters

[0171] Determine the remaining capacity S of the photovoltaic inverter re With D need If the remaining capacity of the photovoltaic inverter is S re Greater than D need , then the inverter will be based on all the kth harmonic current values ​​exceeding the standard I k , phase Y, corresponding output amplitude is I k , the harmonic current with phase -Y is controlled. If the remaining capacity of the photovoltaic inverter is S re Less than D need , then the severity of the harmonic current exceeding the standard is reduced from high to low, and the inverter is based on a certain k-th harmonic current value I k , phase Y, corresponding output amplitude is I k , the phase is -Y harmonic current, after completing a certain harmonic current treatment, calculate the remaining capacity:

[0172]

[0173] I k is the harmonic current that has been output until the remaining capacity is 0. Enter (4).

[0174] (4) Harmonic suppression of energy storage systems

[0175] Re-detect the number of times the harmonics in the system exceed the standard and obtain the harmonic current value I k , phase Y. Recalculate the power requirement:

[0176]

[0177] Determine the remaining capacity S of the energy storage system re With D need If the remaining capacity of the energy storage system is S re Greater than D need , then according to all the kth harmonic current values ​​exceeding the standard I k , phase Y, corresponding output amplitude is I k , the harmonic current with phase -Y is controlled. If the remaining capacity of the energy storage system is S re Less than D need , then the severity of the harmonic current exceeding the standard is reduced from high to low, and according to the k-th harmonic current value I k , phase Y, corresponding output amplitude is I k , the phase is -Y harmonic current, after completing a certain harmonic current treatment, calculate the remaining capacity:

[0178]

[0179] I k It is the harmonic current that has been output until the control is completed or the remaining capacity is 0.

[0180] The implementation method of the voltage and harmonic coordinated control method of the present invention first obtains multiple reactive voltage sensitivities, wherein each reactive voltage sensitivity corresponds to an access node of a distributed power source, and the reactive voltage sensitivity characterizes the influence of reactive power on the node voltage; then the voltage over-limit situation and the harmonic over-standard situation of each access node are analyzed respectively; then for the access nodes with voltage over-limit, according to the voltage over-limit situation, power factor, corresponding reactive voltage sensitivity, remaining capacity of the distributed power source and capacity of the energy storage system of the access node, the active output and reactive output of the distributed power source and the energy storage system are adjusted to control the access nodes with voltage over-limit; finally, after completing the voltage over-limit control, for the access nodes with harmonic over-standard, the harmonic control demand is determined according to the harmonic over-standard situation of the access nodes, and the harmonic output of the distributed power source and the energy storage system is adjusted according to the remaining capacity of the access node and the remaining capacity of the energy storage system. The implementation mode of the present invention analyzes the influence of reactive voltage sensitivity on the voltage of each distributed power supply access node, adjusts the output of the distributed power supply mainly by adjusting reactive power and supplemented by reducing active power output, and when reducing active output, stores the reduced active power through an energy storage device, that is, adjusts the power quality to maximize the consumption of distributed power generation, thereby improving energy utilization; and the implementation mode of the present invention also utilizes the remaining capacity of the distributed power supply and the energy storage device to manage voltage and harmonics, thereby reducing the investment in power management equipment resources.

[0181] It should be understood that the size of the serial numbers of the steps in the above implementation does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the implementation method of the present invention.

[0182] The following is an implementation of the device of the present invention. For details not described in detail, reference may be made to the corresponding method implementation described above.

[0183] Figure 4 This is a functional block diagram of the voltage and harmonic coordination control device provided by the embodiment of the present invention, referring to Figure 4 The voltage and harmonic coordinated control device includes: a voltage reactive power sensitivity determination module 401, a voltage and harmonic excess calculation module 402, a voltage over-limit control module 403 and a harmonic excess control module 404, wherein:

[0184] The voltage reactive power sensitivity determination module 401 is used to obtain a plurality of reactive voltage sensitivities, wherein each reactive voltage sensitivity corresponds to an access node of a distributed power source, and the reactive voltage sensitivity represents the influence of reactive power on the node voltage;

[0185] The voltage and harmonic exceeding standard calculation module 402 is used to analyze the voltage exceeding standard and the harmonic exceeding standard of each access node respectively;

[0186] The voltage over-limit management module 403 is used to adjust the active output and reactive output of the distributed power source and the energy storage system according to the voltage over-limit situation, power factor, corresponding reactive voltage sensitivity, remaining capacity of the distributed power source and capacity of the energy storage system of the access node where the voltage is over-limited, so as to manage the access node where the voltage is over-limited;

[0187] The harmonic excess control module 404 is used to determine the harmonic control requirements for access nodes with excessive harmonics after completing voltage over-limit control, based on the excessive harmonics of the access nodes, and adjust the harmonic output of the distributed power source and the energy storage system based on the remaining capacity of the access nodes and the remaining capacity of the energy storage system.

[0188] Figure 5 is a functional block diagram of an electronic device provided by an embodiment of the present invention. Figure 5 As shown, the electronic device 5 of this embodiment includes: a processor 500 and a memory 501, wherein the memory 501 stores a computer program 502 that can be run on the processor 500. When the processor 500 executes the computer program 502, the steps in the above-mentioned voltage and harmonic coordinated control methods and implementation methods are implemented, such as Figure 1 Steps 101 to 104 are shown.

[0189] Exemplarily, the computer program 502 may be divided into one or more modules / units, and the one or more modules / units are stored in the memory 501 and executed by the processor 500 to implement the present invention.

[0190] The electronic device 5 may be a computing device such as a desktop computer, a notebook, a PDA, or a cloud server. The electronic device 5 may include, but is not limited to, a processor 500 and a memory 501. Those skilled in the art will appreciate that Figure 5 It is only an example of the electronic device 5 and does not constitute a limitation of the electronic device 5. It may include more or fewer components than shown in the figure, or a combination of certain components, or different components. For example, the electronic device 5 may also include input and output devices, network access devices, buses, etc.

[0191] The processor 500 may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor, etc.

[0192] The memory 501 may be an internal storage unit of the electronic device 5, such as a hard disk or memory of the electronic device 5. The memory 501 may also be an external storage device of the electronic device 5, such as a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, etc. equipped on the electronic device 5. Further, the memory 501 may also include both an internal storage unit of the electronic device 5 and an external storage device. The memory 501 is used to store the computer program 502 and other programs and data required by the electronic device 5. The memory 501 may also be used to temporarily store data that has been output or is to be output.

[0193] Those skilled in the art can clearly understand that for the convenience and simplicity of description, only the division of the above-mentioned functional units and modules is used as an example for illustration. In actual applications, the above-mentioned function allocation can be completed by different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the implementation method can be integrated into a processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of software functional units. In addition, the specific names of the functional units and modules are only for the convenience of distinguishing each other, and are not used to limit the scope of protection of this application. The specific working process of the units and modules in the above-mentioned system can refer to the corresponding process in the aforementioned method implementation method, which will not be repeated here.

[0194] In the above-mentioned embodiments, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0195] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present invention.

[0196] In the embodiments provided by the present invention, it should be understood that the disclosed devices / electronic devices and methods can be implemented in other ways. For example, the device / electronic device embodiments described above are only schematic. For example, the division of the modules or units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0197] 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 on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0198] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0199] If the integrated module / unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the present invention implements all or part of the processes in the above-mentioned implementation method, and can also be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium. When the computer program is executed by the processor, it can implement the steps of the above-mentioned various methods and device implementation methods. Among them, the computer program includes computer program code, and the computer program code can be in source code form, object code form, executable file or some intermediate form. The computer-readable medium may include: any entity or device that can carry the computer program code, recording medium, U disk, mobile hard disk, disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signal, telecommunication signal and software distribution medium.

[0200] The above-described embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention, and should all be included in the protection scope of the present invention.

Claims

1. A voltage and harmonic coordinated control method, characterized in that: include: Acquire multiple reactive voltage sensitivities, wherein each reactive voltage sensitivity corresponds to an access node of a distributed power source, and the reactive voltage sensitivity represents the influence of reactive power on node voltage; Analyze the voltage over-limit and harmonic over-limit conditions of each access node respectively; For access nodes with voltage exceeding the limit, the active and reactive outputs of the distributed power sources and the energy storage system are adjusted according to the voltage exceeding the limit, power factor, corresponding reactive voltage sensitivity, remaining capacity of the distributed power sources and capacity of the energy storage system, so as to manage the access nodes with voltage exceeding the limit; After completing the voltage over-limit control, for the access nodes with excessive harmonics, the harmonic control requirements are determined based on the excessive harmonics of the access nodes, and the harmonic output of the distributed power source and the energy storage system are adjusted based on the remaining capacity of the access nodes and the remaining capacity of the energy storage system.

2. The voltage and harmonic coordinated control method according to claim 1 is characterized in that: The obtaining of multiple reactive voltage sensitivities comprises: The multiple reactive voltage sensitivities are determined according to a first formula, a transformer outlet voltage value, and a line impedance value between an access node and a transformer node, wherein the first formula is: In the formula, S Ui is the reactive voltage sensitivity, V s is the transformer outlet voltage, X i Represents the line impedance value between the i-th access node and the transformer node.

3. The voltage and harmonic coordinated control method according to claim 1 is characterized in that: The respectively analyzing the harmonic exceeding standard situation of each access node includes: The voltage total harmonic distortion rate of each access node is determined according to the second formula, the effective value of the fundamental voltage of the access point, and the root mean square values ​​of multiple harmonic voltages, wherein the second formula is: Where, THD U,i (t) is the total harmonic distortion rate of the voltage at access node i at time t, U h,i (t) is the root mean square value of the harmonic voltage of the access node i at time t, U 1,i (t) is the effective value of the fundamental voltage of access node i at time t, and H is the maximum harmonic order.

4. The voltage and harmonic coordinated control method according to claim 1 is characterized in that: For the access node with voltage exceeding the limit, the active output and reactive output of the distributed power source and the energy storage system are adjusted according to the voltage exceeding the limit, the power factor, the corresponding reactive voltage sensitivity, the remaining capacity of the distributed power source and the capacity of the energy storage system of the access node, so as to manage the access node with voltage exceeding the limit, including: Determine the remaining capacity of the distributed generation at the over-limit access node; Determine the reactive power compensation amount based on the voltage over-limit situation of the access node, the corresponding reactive power voltage sensitivity and the remaining capacity of the distributed power source; If the voltage exceeds the upper limit and the power factor of the access node is less than the target power factor, the reactive output of the distributed power source is adjusted according to the reactive compensation amount; If the voltage exceeds the upper limit and the power factor of the access node is greater than the target power factor, the active output of the distributed power source connected to the grid is reduced, and the reduced active output is used to store energy in the energy storage system. When the reduced active output of the distributed power source reaches the upper limit and the voltage still exceeds the upper limit, the reactive output of the distributed power source is adjusted; If the voltage exceeds the upper limit and the power factor of the access node is equal to the target power factor, the reactive power control of the energy storage system is adjusted; If the voltage exceeds the lower limit, the active or reactive output of the energy storage system is adjusted according to the remaining energy of the energy storage system.

5. The voltage and harmonic coordinated control method according to claim 4 is characterized in that: The step of determining the reactive power compensation amount of the distributed power source according to the voltage over-limit condition of the access node, the corresponding reactive voltage sensitivity, and the remaining capacity of the distributed power source includes: The reactive compensation amount of the distributed power source is determined according to the third formula, the voltage over-limit condition of the access node, the corresponding reactive voltage sensitivity, and the remaining capacity of the distributed power source, wherein the third formula is: In the formula, Q PV1 is the reactive power compensation of distributed power source, V low 、V lb 、V ub 、V up They are the lower voltage limit for equipment operation, the lower voltage limit for safe operation of the distribution network, the upper voltage limit for equipment operation, and the upper voltage limit for safe operation of the distribution network. max is the maximum adjustable reactive capacity of the distributed generation at the corresponding node, ρ min is the minimum power factor of distributed power supply, S re is the remaining capacity of distributed generation, S inv is the capacity of distributed generation, S Ui is the reactive voltage sensitivity, M is a constant greater than zero, V PCC is the voltage at the access point, P pv It is the active power of distributed power source; The reducing the active output of the distributed power source connected to the grid includes: The active power adjustment step length is determined according to the fourth formula, and the fourth formula is: In the formula, ΔP pv is the active power adjustment step size, P rated is the rated active power, X is the adjustment ratio, ΔP max is the maximum active power adjustment step, Q pv is the reactive power of distributed generation, ρ min is the lower limit of power factor; Reducing the active power output of the distributed power source connected to the grid according to the active power adjustment step size; If the voltage does not reach the safety level, the process jumps to the step of determining the active power adjustment step size according to the fourth formula.

6. The voltage and harmonic coordinated control method according to claim 4 is characterized in that: The step of adjusting the reactive output of the energy storage system comprises: The reactive output compensation amount of the energy storage system is determined according to the fifth formula, wherein the fifth formula is: Where V low 、V lb 、V ub 、V up They are the lower voltage limit for equipment operation, the lower voltage limit for safe operation of the distribution network, the upper voltage limit for equipment operation, and the upper voltage limit for safe operation of the distribution network. ESS is the rated capacity of the energy storage system, Q ESS is the reactive output compensation of the energy storage system, X i represents the line impedance value between the i-th access node and the transformer node; Adjust the reactive output of the energy storage system according to the reactive output compensation amount of the energy storage system; When the voltage exceeds the lower limit, the active or reactive output of the energy storage system is adjusted according to the residual energy of the energy storage system, including: If the remaining energy of the energy storage system is greater than zero, discharge is performed according to the remaining energy of the energy device; Otherwise, the reactive output compensation amount of the energy storage system is determined according to the fifth formula, and the reactive output of the energy storage system is adjusted according to the reactive output compensation amount of the energy storage system.

7. The voltage and harmonic coordinated control method according to any one of claims 1 to 6, characterized in that: Determining the harmonic control demand according to the harmonic exceeding standard of the access node, and adjusting the harmonic output of the distributed power source and the energy storage system according to the remaining capacity of the access node and the remaining capacity of the energy storage system, includes: The harmonic control requirement is determined according to the sixth formula, wherein the sixth formula is: Where U 1,PV is the effective value of the fundamental voltage at the grid-connected point at that moment, n is the maximum harmonic order that the inverter can control, I k is the hth harmonic current of the access node; The remaining capacity of the distributed power source and the remaining capacity of the energy storage device are determined according to the seventh formula, wherein the seventh formula is: In the formula, S re is the remaining capacity of distributed generation, S ESS is the remaining capacity of the energy storage device, P pv is the active power output of the distributed power source, Q pv is the reactive power output of distributed power generation, S inv is the capacity of the inverter, P ESS is the charging and discharging power of the energy storage device, Q pv is the reactive output of the energy storage device, S ESS is the capacity of the energy storage device; According to the harmonic control demand, the remaining capacity of the distributed power source and the remaining capacity of the energy storage device, the harmonic current with the same amplitude and opposite phase as the harmonic current is preferentially output from the distributed power source. When the remaining capacity of the distributed power source is exhausted, the harmonic current with the same amplitude and opposite phase as the harmonic current is output from the energy storage device.

8. A voltage and harmonic coordinated control device, characterized in that: Used to implement the voltage and harmonic coordinated governance method according to any one of claims 1 to 7, the voltage and harmonic coordinated governance device comprises: A voltage reactive power sensitivity determination module is used to obtain multiple reactive voltage sensitivities, wherein each reactive voltage sensitivity corresponds to an access node of a distributed power source, and the reactive voltage sensitivity represents the influence of reactive power on the node voltage; The voltage and harmonic excess calculation module is used to analyze the voltage over-limit situation and harmonic excess situation of each access node respectively; The voltage over-limit management module is used to adjust the active and reactive outputs of the distributed power supply and the energy storage system according to the voltage over-limit situation, power factor, corresponding reactive voltage sensitivity, remaining capacity of the distributed power supply and capacity of the energy storage system of the access node where the voltage is over-limited, so as to manage the access node where the voltage is over-limited; as well as, The harmonic excess control module is used to determine the harmonic control requirements for access nodes with excessive harmonics after completing voltage over-limit control, based on the harmonic excess situation of the access nodes, and adjust the harmonic output of the distributed power supply and the energy storage system based on the remaining capacity of the access nodes and the remaining capacity of the energy storage system.

9. An electronic device comprising a memory and a processor, wherein the memory stores a computer program that can be run on the processor, characterized in that: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the steps of the method as claimed in any one of claims 1 to 7 are implemented.

Images