High-altitude power equipment condition monitoring system and method

Abstract

The invention discloses a high-altitude power equipment condition monitoring system and method, and relates to the field of data analysis. According to the main scheme, the method comprises the following steps: calculating a power equipment operation state index X according to a photovoltaic power generation-energy storage system cooperation efficiency index WA, a power transmission line stability index WB, a photovoltaic power generation-inversion cooperation index WC, a photovoltaic power generation system index WD and an energy storage system state index WE; and judging the operation state of the power equipment according to the operation state index X and the operation state threshold set of the power equipment, thereby solving the problems that the traditional monitoring system usually only pays attention to the operation state of single equipment and neglects the cooperative work relationship between different equipment and each system, so that the operation state of the whole optical storage project cannot be comprehensively evaluated, and the working efficiency is low. And a systematic potential problem is difficult to find in time.

Description

Technical Field

[0001] The present invention relates to the technical field of data analysis, and in particular to a high-altitude power equipment condition monitoring system and method. Background Art

[0002] In ultra-high altitude areas, environmental conditions are harsh, such as low temperature, low air pressure, strong ultraviolet rays and other factors that have a greater impact on photovoltaic storage equipment. By using high-altitude power equipment condition monitoring methods to monitor ultra-high altitude photovoltaic storage projects, the operating data of the equipment can be obtained in real time, which is conducive to the early detection of potential fault hazards, enhancing system safety, and reducing operation and maintenance costs and difficulties.

[0003] Traditionally, the status of high-altitude power equipment is monitored by installing sensors on the power equipment to collect the equipment's operating parameters, such as temperature, voltage, current, etc. The system pre-sets the normal operating threshold range for each parameter. When the collected parameters exceed this range, an alarm is triggered.

[0004] Existing technologies still have the following shortcomings: traditional monitoring systems often only focus on the operating status of a single device, ignoring the collaborative working relationship between different devices and various systems, resulting in an inability to comprehensively evaluate the operating status of the entire photovoltaic storage project and difficulty in timely discovering potential systemic problems. Summary of the invention

[0005] 1. Technical issues to be resolved

[0006] In view of the deficiencies in the prior art, the present invention provides a high-altitude power equipment status monitoring system and method, which calculates the power equipment operation status index X according to the photovoltaic power generation-energy storage system collaborative efficiency index WA, the transmission line stability index WB, the photovoltaic power generation-inverter collaborative index WC, the photovoltaic power generation system index WD and the energy storage system status index WE, and judges the power equipment operation status according to the power equipment operation status index X and the operation status threshold set, thereby solving the problem that traditional monitoring systems often only focus on the operation status of a single device, ignoring the collaborative working relationship between different devices and various systems, resulting in the inability to comprehensively evaluate the operation status of the entire photovoltaic storage project and difficulty in timely discovering systemic potential problems.

[0007] (II) Technical solution

[0008] To achieve the above objectives, the present invention is implemented through the following technical solutions: A method for monitoring the condition of high-altitude power equipment, comprising the following steps:

[0009] Collect photovoltaic power generation system data, energy storage system data, overall data, inverter and grid-connected system data and transmission line data of the photovoltaic storage project;

[0010] Calculate the photovoltaic power generation-energy storage system synergy efficiency index WA based on the photovoltaic power generation system data, energy storage system data and overall data; calculate the transmission line stability index WB based on the inverter and grid-connected system data and the transmission line data; calculate the power transmission consistency index QA based on the inverter and grid-connected system data, and calculate the photovoltaic power generation-inverter synergy index WC based on the power transmission consistency index QA, photovoltaic power generation system data and inverter and grid-connected system data; calculate the photovoltaic power generation system index WD based on the photovoltaic power generation system data; calculate the energy storage system status index WE based on the energy storage system data; calculate the power equipment operation status index X based on the photovoltaic power generation-energy storage system synergy efficiency index WA, the transmission line stability index WB, the photovoltaic power generation-inverter synergy index WC, the photovoltaic power generation system index WD and the energy storage system status index WE;

[0011] A set of operating status thresholds is preset; the operating status of the power equipment is judged according to the operating status indicator X of the power equipment and the operating status threshold set, and an early warning method is selected according to the operating status of the power equipment.

[0012] In the preferred embodiment of the above-mentioned method for monitoring the condition of power equipment at high altitude, the method for calculating the photovoltaic power generation-energy storage system synergy efficiency index WA is:

[0013] Photovoltaic power generation system data includes photovoltaic module output power AA a and the starting time AE of the PV module power change;

[0014] Energy storage system data includes energy storage system charging and discharging power AB a and the energy storage system starts responding at AF;

[0015] The overall data includes the useful power AC to meet the load demand a ;

[0016] The photovoltaic power generation-energy storage system synergy efficiency index WA is calculated based on the photovoltaic power generation system data, energy storage system data and overall data. The formula is:

[0017]

[0018] Among them, AA a is the output power of the photovoltaic module at the ath sampling time point, a is the serial number corresponding to different sampling time points, and its value is [1, b]; b is the total number of sampling time points, and its value is a positive integer; AB a is the charging or discharging power of the energy storage system at the ath sampling time point; AC a is the useful power that meets the load demand at the ath sampling time point.

[0019] In the preferred embodiment of the above-mentioned method for monitoring the condition of electric power equipment at high altitude, the method for calculating the stability index WB of the power transmission line is:

[0020] Inverter and grid-connected system data including inverter harmonic current RMS value BA d , fundamental current effective value BB and output current rated effective value BD;

[0021] The transmission line data includes the transmission line resistance CA and the transmission line reactance CB;

[0022] The transmission line stability index WB is calculated based on the inverter and grid-connected system data and the transmission line data, and the formula is:

[0023]

[0024] Among them, BA d is the effective value of the harmonic current of the dth harmonic, d is the serial number corresponding to different harmonics, and its value is [1, f]; f is the total number of harmonics, and its value is a positive integer.

[0025] In the preferred embodiment of the above-mentioned method for monitoring the condition of electric power equipment at high altitude, the method for calculating the power transmission consistency index QA is:

[0026] Inverter and grid-connected system data also includes inverter input power DA a and inverter output power DB a ;

[0027] According to the inverter input power DA a and inverter output power DB a The power transmission consistency indicator QA is calculated based on the formula:

[0028]

[0029] Among them, DA a is the input power of the inverter at the ath sampling time point; DB a is the output power of the inverter at the ath sampling time point.

[0030] In the preferred embodiment of the above-mentioned method for monitoring the condition of power equipment at high altitude, the method for calculating the photovoltaic power generation-inversion coordination index WC is:

[0031] Photovoltaic power generation system data also includes output voltage frequency EA;

[0032] The inverter and grid-connected system data also include grid frequency EB, grid rated frequency EC, inverter conversion efficiency ED and inverter conversion efficiency average EE;

[0033] The photovoltaic power generation-inverter synergy index WC is calculated based on the power transmission consistency index QA, output voltage frequency EA, grid frequency EB, grid rated frequency EC, inverter conversion efficiency ED and inverter conversion efficiency average EE. The formula is:

[0034]

[0035] Among them, 1 is the weight coefficient of the power transmission consistency index QA, and its value is 0.3~0.5; 2 for The weight coefficient is 0.2~0.5; 3 for The weight coefficient is 0.2~0.5; and 1 +ɑ 2 +ɑ 3 =1.

[0036] In the preferred embodiment of the above-mentioned method for monitoring the condition of power equipment at high altitude, the method for calculating the photovoltaic power generation system index WD is:

[0037] Photovoltaic power generation system data also includes the output voltage FA of each branch of the DC cabinet i , branch output voltage average FB, each branch output current FC i , the average value of branch output current FD and the rated power FE of the PV module;

[0038] According to the output voltage FA of each branch of the DC cabinet i , branch output voltage average FB, each branch output current FC i , average branch output current FD, PV module output power AA a The formula for calculating the photovoltaic power generation system index WD based on the rated power FE of the photovoltaic modules is:

[0039]

[0040] Among them, FA i is the output voltage of the i-th branch in the DC cabinet, i is the serial number corresponding to different branches, and its value is [1, m]; m is the total number of branches in the DC cabinet, and its value is a positive integer; FC i is the output current of the i-th branch in the DC cabinet.

[0041] In the above preferred embodiment of the method for monitoring the condition of power equipment at high altitude, the method for calculating the energy storage system state index WE is:

[0042] The energy storage system data also includes the initial charge state GA, the rated capacity of the battery pack GB, the battery pack charge and discharge current GC(t), the initial internal resistance of the battery pack GD and the current internal resistance of the battery pack GE;

[0043] The energy storage system status indicator WE is calculated based on the initial charge state GA, the rated capacity of the battery pack GB, the battery pack charge and discharge current GC(t), the initial internal resistance of the battery pack GD and the current internal resistance of the battery pack GE. The formula is as follows:

[0044]

[0045] Among them, GC(t) is the charge and discharge current of the battery pack at time point t, t is the sequence number corresponding to different time points, and t1 is the duration of the detection cycle.

[0046] In the preferred embodiment of the above-mentioned method for monitoring the condition of electric power equipment at high altitude, the method for calculating the operating status index X of the electric power equipment is:

[0047] The power equipment operation status index X is calculated based on the photovoltaic power generation-energy storage system coordination efficiency index WA, the transmission line stability index WB, the photovoltaic power generation-inverter coordination index WC, the photovoltaic power generation system index WD and the energy storage system status index WE.

[0048] The formula is:

[0049]

[0050] In the preferred embodiment of the above-mentioned method for monitoring the condition of power equipment at high altitude, the method for judging the operating status of the power equipment is:

[0051] The operating state threshold set includes a normal operating state threshold YC, a medium risk threshold YZ, and a high risk threshold YG;

[0052] The operating state of the power equipment is judged according to the power equipment operating state index X and the operating state threshold set, and the standard is as follows:

[0053]

[0054] When it is in normal operation, select early warning mode 1;

[0055] When the operation is in a low-risk state, select early warning method 2;

[0056] When the operating state is medium risk, select early warning method three;

[0057] When the operating state is high risk, select warning method four.

[0058] The present invention also discloses a high-altitude power equipment condition monitoring system, comprising:

[0059] Data acquisition module, used to collect photovoltaic power generation system data, energy storage system data, overall data, inverter and grid-connected system data and transmission line data of the photovoltaic storage project;

[0060] The index calculation module can calculate the photovoltaic power generation-energy storage system coordination efficiency index WA based on the photovoltaic power generation system data, the energy storage system data and the overall data; calculate the transmission line stability index WB based on the inverter and grid-connected system data and the transmission line data; calculate the power transmission consistency index QA based on the inverter and grid-connected system data, and calculate the photovoltaic power generation-inverter coordination index WC according to the power transmission consistency index QA, the photovoltaic power generation system data and the inverter and grid-connected system data; calculate the photovoltaic power generation system index WD based on the photovoltaic power generation system data; calculate the energy storage system status index WE based on the energy storage system data; calculate the power equipment operation status index X according to the photovoltaic power generation-energy storage system coordination efficiency index WA, the transmission line stability index WB, the photovoltaic power generation-inverter coordination index WC, the photovoltaic power generation system index WD and the energy storage system status index WE;

[0061] The judgment module can preset an operation status threshold set; judge the operation status of the power equipment according to the power equipment operation status indicator X and the operation status threshold set, and select an early warning method according to the operation status of the power equipment.

[0062] (III) Beneficial effects

[0063] The present invention provides a high-altitude power equipment condition monitoring system and method, which has the following beneficial effects:

[0064] (1) By collecting the photovoltaic power generation system data, energy storage system data, overall data, inverter and grid-connected system data, and transmission line data of the photovoltaic storage project, the operating status of the photovoltaic storage project can be evaluated from multiple dimensions, which is conducive to improving the accuracy of the evaluation.

[0065] (2) The photovoltaic power generation-energy storage system synergy efficiency index WA is calculated based on the photovoltaic power generation system data, energy storage system data and overall data. It can accurately measure the synergy between the photovoltaic power generation system and the energy storage system in actual operation, which is helpful to determine the optimal configuration ratio of the photovoltaic power generation system and the energy storage system. The transmission line stability index WB is calculated based on the inverter and grid-connected system data and the transmission line data. It can not only reflect the status of the transmission line itself, but also reflect the impact of the inverter and grid-connected system on the transmission stability. It can fully grasp the various factors in the transmission process and help to discover potential system weaknesses. The photovoltaic power generation-inverter synergy index WC is calculated based on the photovoltaic power generation system data and the inverter and grid-connected system data. It comprehensively considers the data of the two key links of photovoltaic power generation and inverter grid connection, and can comprehensively evaluate the efficiency of the entire power generation and grid connection process. It can intuitively show whether the two can cooperate efficiently under different working conditions, providing a key reference for evaluating the overall performance of the system. The power generation system indicator WD can reflect the operating status of the photovoltaic power generation system in real time, understand the power generation level of the system under different lighting conditions, and evaluate whether it meets the design requirements and expected goals. The energy storage system status indicator WE is calculated based on the energy storage system data, which can understand the energy storage level of the energy storage system and the loss in the energy conversion process, and provide a reference for optimizing system operation. The power equipment operating status indicator X is calculated based on the photovoltaic power generation-energy storage system collaborative efficiency indicator WA, the transmission line stability indicator WB, the photovoltaic power generation-inverter collaborative indicator WC, the photovoltaic power generation system indicator WD and the energy storage system status indicator WE, which is conducive to a comprehensive analysis of the overall operating status of the equipment, avoiding misjudgment or missed judgment caused by a single indicator judgment, and solving the problem that traditional monitoring systems often only focus on the operating status of a single device, ignoring the collaborative working relationship between different devices and various systems, resulting in an inability to comprehensively evaluate the operating status of the entire photovoltaic storage project and difficult to timely discover systemic potential problems.

[0066] (3) Judging the operating status of the power equipment based on the power equipment operating status indicator X and the operating status threshold set can reflect the equipment status in real time and provide accurate equipment operating information for operation and maintenance personnel. Selecting the early warning method based on the operating status of the power equipment is conducive to discovering potential problems and hidden faults of the equipment in advance, avoiding the occurrence of equipment failures, and ensuring the stable operation of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0067] Figure 1 The figure is a schematic diagram of the working steps of a method for monitoring the condition of electric power equipment at high altitudes according to the present invention. DETAILED DESCRIPTION

[0068] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0069] See also Figure 1 The present invention provides a method for monitoring the condition of high-altitude power equipment, comprising the following steps:

[0070] Step 1: Collect the photovoltaic power generation system data, energy storage system data, overall data, inverter and grid-connected system data and transmission line data of the photovoltaic storage project.

[0071] Combined with the content of step 1:

[0072] By collecting the photovoltaic power generation system data, energy storage system data, overall data, inverter and grid-connected system data and transmission line data of the photovoltaic storage project, the operating status of the photovoltaic storage project can be evaluated from multiple dimensions, which is conducive to improving the accuracy of the evaluation.

[0073] Step 2: Calculate the photovoltaic power generation-energy storage system synergy efficiency index WA based on the photovoltaic power generation system data, the energy storage system data and the overall data; calculate the transmission line stability index WB based on the inverter and grid-connected system data and the transmission line data; calculate the power transmission consistency index QA based on the inverter and grid-connected system data, and calculate the photovoltaic power generation-inverter synergy index WC based on the power transmission consistency index QA, the photovoltaic power generation system data and the inverter and grid-connected system data; calculate the photovoltaic power generation system index WD based on the photovoltaic power generation system data; calculate the energy storage system status index WE based on the energy storage system data; calculate the power equipment operation status index X based on the photovoltaic power generation-energy storage system synergy efficiency index WA, the transmission line stability index WB, the photovoltaic power generation-inverter synergy index WC, the photovoltaic power generation system index WD and the energy storage system status index WE.

[0074] Step 2 includes the following steps:

[0075] Step 201: The method for calculating the photovoltaic power generation-energy storage system synergy efficiency index WA is:

[0076] Photovoltaic power generation system data includes photovoltaic module output power AA a And the starting time AE of the PV module power change.

[0077] It should be noted that when monitoring and analyzing the photovoltaic power generation system, it is necessary to collect the output power data of the photovoltaic modules at multiple sampling time points. These sampling time points can be equally spaced time points, such as collecting power data every 1 minute, 5 minutes or 10 minutes. The output power of the photovoltaic module AA a It refers to the amount of electric power that a photovoltaic module converts solar energy into electrical energy and outputs at a certain sampling time point. It reflects the power generation capacity under the combined effect of multiple factors such as light intensity, temperature, and module performance at that time. The unit is watt and is measured and obtained by installing a high-precision power sensor at the output end of the photovoltaic module. The starting time AE of the photovoltaic module power change refers to the time point when the output power of the photovoltaic module begins to change significantly. The method of obtaining it is: calculate the difference in power between two adjacent sampling time points. When the difference is greater than 5% of the rated power of the photovoltaic module, it is considered that the power begins to change significantly. The time point corresponding to the next sampling time point in the difference calculation is the starting time AE of the photovoltaic module power change.

[0078] Energy storage system data includes energy storage system charging and discharging power AB a And the energy storage system starts to respond at time AF.

[0079] It should be noted that the energy storage system charging and discharging power AB a It refers to the power of the energy storage system releasing electric energy to the outside or absorbing electric energy from the outside at a certain moment. When discharging, the power value is positive, indicating that the energy storage system is supplying power to the outside as a power source. When charging, the power value is negative, indicating that the energy storage system is obtaining electric energy from the outside as a load. It is a key indicator to measure the working state and energy throughput capacity of the energy storage system. The unit is watt, and it is measured and obtained by installing power sensors at the input and output ends of the energy storage system. The energy storage system starts to respond AF refers to the time point when the energy storage system starts to adjust its charging and discharging power to respond when the output power of the photovoltaic power generation system changes. The acquisition method is: set a signal trigger detection mechanism in the control signal circuit or power regulation device of the energy storage system. When a signal is received that the charging and discharging power needs to be changed due to the change in the power of the photovoltaic module, the reception time of this signal is recorded as the energy storage system starts to respond AF.

[0080] The overall data includes the useful power AC to meet the load demand a .

[0081] It should be noted that the useful power AC that meets the load demand aIt refers to the power provided by the photovoltaic power generation system and the energy storage system to the load, which can be effectively used by the load to complete the expected function. The unit is watt. The acquisition method is: install a power sensor at the input port of each load, and accumulate the power values ​​measured at the same sampling time point as the useful power AC that meets the load demand. a .

[0082] The photovoltaic power generation-energy storage system synergy efficiency index WA is calculated based on the photovoltaic power generation system data, energy storage system data and overall data. The formula is:

[0083]

[0084] Among them, AA a is the output power of the photovoltaic module at the ath sampling time point, a is the serial number corresponding to different sampling time points, and its value is [1, b]; b is the total number of sampling time points, and its value is a positive integer; AB a is the charging or discharging power of the energy storage system at the ath sampling time point; AC a is the useful power that meets the load demand at the ath sampling time point.

[0085] It should be noted that the operating principle of this formula is: It is the cumulative value of the effective power actually provided by the system to the load at each moment, reflecting the part of the system output power that is actually used by the load. It is the sum of the absolute values ​​of the photovoltaic module power generation and the energy storage system charging and discharging power, which represents the potential energy supply capacity of the system. The ratio of effectively utilized power to total input power reflects the degree of effective utilization of the system in terms of energy supply. A higher ratio indicates that the system can more effectively convert its potential energy supply into actual power useful to the load, and the system performs better in terms of energy utilization and coordination. The reaction speed of the energy storage system to the power change of the photovoltaic module is measured by calculating the time interval from the power change to the response of the energy storage system. The shorter the time interval, the faster the reaction speed and the better the synergy effect. This formula multiplies the two indicators and comprehensively considers the impact of the two indicators to obtain the photovoltaic power generation-energy storage system synergy efficiency index WA.

[0086] Step 202: The method for calculating the transmission line stability index WB is:

[0087] Inverter and grid-connected system data including inverter harmonic current RMS value BA d , fundamental current effective value BB and output current rated effective value BD.

[0088] It should be noted that the harmonic current effective value BA dIt refers to the effective value of the current of other frequency components except the fundamental frequency in the inverter output current. The fundamental current effective value BB refers to the effective value of the sinusoidal current with the same frequency as the grid frequency in the inverter output current. It is the main component of the inverter output current and determines the size of the active power provided by the inverter to the load. The harmonic current effective value BA d The fundamental current effective value BB is measured and obtained using a power quality analyzer, and the unit is ampere. The output current rated effective value BD refers to the effective value of the current that the inverter can output stably for a long time under the conditions of rated input voltage and rated power. It can be obtained by checking the inverter nameplate or technical specification, and the unit is ampere.

[0089] The transmission line data includes the transmission line resistance CA and the transmission line reactance CB.

[0090] It should be noted that the transmission line resistance CA refers to the characteristic of hindering the flow of current when the current passes through the transmission line, which is caused by the conversion of electrical energy into heat energy due to the resistivity of the material of the line conductor itself, as well as the cross-sectional area and length of the conductor. The unit is ohm, and the method of obtaining it is: use a multimeter to measure the resistance at different positions on the transmission line, accumulate the measured resistance data and divide it by the number of data, as the transmission line resistance CA. The transmission line reactance CB is the resistance to the current formed by the magnetic field generated by the current around the transmission line, and the self-inductance and mutual inductance effects generated by the alternating current in the conductor. The unit is ohm, and the method of obtaining it is: use an impedance analyzer to measure the reactance at different positions on the transmission line, accumulate the measured reactance data and divide it by the number of data, as the transmission line reactance CB.

[0091] The transmission line stability index WB is calculated based on the inverter and grid-connected system data and the transmission line data, and the formula is:

[0092]

[0093] Among them, BA d is the effective value of the harmonic current of the dth harmonic, d is the serial number corresponding to different harmonics, and its value is [1, f]; f is the total number of harmonics, and its value is a positive integer.

[0094] It should be noted that the operating principle of this formula is: It is a constant related to the characteristics of the three-phase circuit and is used to consider the phase relationship and power transfer characteristics of the three-phase system. The impedance of the transmission line. The greater the impedance, the greater the resistance to the current and the greater the impact on the stability of the transmission line. The output current rated effective value BD represents the maximum current capacity that the inverter can output. The larger the value, the greater the current that the inverter can provide, the greater the voltage drop and power loss generated on the transmission line, and the greater the impact on the stability of the transmission line. It is the ratio of harmonic current to fundamental current. This ratio can reflect the degree of harmonic distortion of inverter output current. The higher the degree of harmonic distortion, the greater the impact on the stability of the transmission line. This formula quantitatively evaluates the stability of the transmission line by comprehensively considering the inverter and grid-connected system data and transmission line data to obtain the transmission line stability index WB.

[0095] Step 203: The method for calculating the power transmission consistency index QA is:

[0096] Inverter and grid-connected system data also includes inverter input power DA a and inverter output power DB a .

[0097] It should be noted that the inverter input power DA a Refers to the electrical power supplied to the inverter. It is the energy source for the inverter to work. The input power determines the upper limit of the inverter's output AC power. It also reflects the power supply capacity of the DC power supply. The inverter output power DB a It refers to the power output after the inverter converts the input DC power into AC power. It is the power actually provided by the inverter to the AC load. The size and stability of the output power directly affect the normal operation of the load. The inverter input power DA a and inverter output power DB a The power is measured by connecting a power sensor in series between the DC power supply and the inverter input terminals. The unit is watt.

[0098] According to the inverter input power DA a and inverter output power DB a The power transmission consistency indicator QA is calculated based on the formula:

[0099]

[0100] Among them, DA a is the input power of the inverter at the ath sampling time point; DB a is the output power of the inverter at the ath sampling time point.

[0101] It should be noted that the operating principle of this formula is: the numerator is the sum of the multiplication of the input power and the output power at each sampling time point. This part is a measure of the degree of correlation between the input power and the output power at each sampling moment. If at a certain sampling time point, the input power and the output power are both large, then their product is also large, and the contribution to the numerator is large. Conversely, if one of the powers is small, the product is small, and the contribution to the numerator is also small. By summing up this product at all sampling time points, the sum of the degree of correlation between the input power and the output power in the entire sampling time period is obtained. The denominator is the normalization of the overall scale of the input power and the output power. This formula evaluates the synergistic relationship between the two by calculating the correlation between the state of charge of the energy storage system and the output power of the inverter. The stronger the correlation, the higher the degree of correlation between the input power and the output power of the inverter at each sampling time point, the better the consistency of the power transmission, and the higher the power transmission consistency index QA.

[0102] Step 204: The method for calculating the photovoltaic power generation-inverter coordination index WC is:

[0103] Photovoltaic power generation system data also includes output voltage frequency EA.

[0104] It should be noted that the output voltage frequency EA refers to the number of times the output AC voltage changes periodically per second after the inverter converts the DC power generated by the solar panel into AC power. The unit is Hertz and is measured using a frequency meter.

[0105] The inverter and grid-connected system data also include grid frequency EB, grid rated frequency EC, inverter conversion efficiency ED and inverter conversion efficiency average EE.

[0106] It should be noted that the grid frequency EB refers to the frequency of the alternating current in the grid. It is one of the important indicators for measuring power quality. Its unit is Hertz and it is measured and obtained using a frequency meter. Specifically, the voltage input terminal of the frequency meter is connected to the AC bus of the grid. The frequency meter will automatically detect and display the grid frequency value, which is the grid frequency EB. The grid rated frequency EC refers to the standard frequency value based on which the grid is designed and operated. In China, the rated frequency of the grid is 50Hz. The inverter conversion efficiency ED refers to the efficiency of the inverter in converting the input DC power into the output AC power. It is one of the important indicators for measuring the performance of the inverter. The acquisition method is: Use a power analyzer to measure the input DC power and output AC power of the inverter respectively. The inverter conversion efficiency ED is calculated according to the formula (inverter output power / inverter input power) × 100%. The average inverter conversion efficiency EE refers to the average value of the inverter conversion efficiency within a period of time. It is a comprehensive evaluation of the conversion efficiency of the inverter under different working conditions. The acquisition method is: within a unit time, such as a day, a week, or a month, use a power analyzer to measure the input DC power and output AC power of the inverter for multiple times, and calculate the inverter conversion efficiency according to the formula (inverter output power / inverter input power) × 100%. Add up all the conversion efficiency values ​​measured within the unit time, and then divide it by the number of measurements to get the average inverter conversion efficiency EE.

[0107] The photovoltaic power generation-inverter synergy index WC is calculated based on the power transmission consistency index QA, output voltage frequency EA, grid frequency EB, grid rated frequency EC, inverter conversion efficiency ED and inverter conversion efficiency average EE. The formula is:

[0108]

[0109] Among them, 1 is the weight coefficient of the power transmission consistency index QA, which is 0.3-0.5 and is determined according to the importance of the power transmission consistency index QA to the photovoltaic power generation-inverter coordination index WC; 2 for The weight coefficient is 0.2 to 0.5. Determine the importance of photovoltaic power generation-inverter synergy index WC; 3 for The weight coefficient is 0.2 to 0.5. The importance of the photovoltaic power generation-inverter synergy index WC is determined; and 1 +ɑ 2 +ɑ 3 =1.

[0110] It should be noted that the operating principle of this formula is: when connected to the grid, the AC frequency output by the photovoltaic power generation system needs to be synchronized with the grid frequency. is the relative ratio of the absolute value of the difference between the output voltage frequency and the grid frequency to the rated frequency of the grid, It means that the relative proportion is inversely proportional to the final index. The smaller it is, the higher the matching degree between the output voltage frequency and the power grid is. The larger it is, the higher the matching degree between the output voltage and the grid frequency is, and the greater the contribution to the final index is. It represents the ratio of the current inverter conversion efficiency to the average conversion efficiency. The larger the ratio is, the higher the stability of the efficiency conversion is, indicating that the coordination between the photovoltaic power generation system and the inverter and grid-connected system in the process of power conversion is more stable. This formula obtains the photovoltaic power generation-inverter coordination index WC by weighted summing the three factors of power transmission consistency, frequency synchronization coordination and inverter conversion efficiency.

[0111] Step 205: The method for calculating the photovoltaic power generation system index WD is:

[0112] Photovoltaic power generation system data also includes the output voltage FA of each branch of the DC cabinet i , branch output voltage average FB, each branch output current FC i , the average value of branch output current FD and the rated power FE of the PV module.

[0113] It should be noted that the output voltage FA of each branch of the DC cabinet i It refers to the DC voltage value measured from the output end of each branch of the DC cabinet, in volts. These voltage values ​​reflect the potential difference of the DC power output by the photovoltaic components or photovoltaic arrays in each branch. It is one of the important parameters for evaluating the power generation performance and power transmission status of the photovoltaic system. It is measured and obtained using a DC voltmeter. The DC cabinet is a device used to collect and distribute DC power in the photovoltaic power generation system. The branch output voltage average value FB refers to the arithmetic mean of the output voltages of all branches of the DC cabinet, in volts. It can reflect the average level of the overall output voltage of the DC cabinet and is used for macro-evaluation of the output voltage status of the DC cabinet. The acquisition method is: use a DC voltmeter to obtain the output voltage values ​​of each branch of the DC cabinet at the same time, add these voltage values ​​and divide them by the number of branches as the branch output voltage average value FB, and the output current FC of each branch iRefers to the actual DC current flowing through each branch of the DC cabinet, in amperes. It reflects the ability of the PV modules or PV arrays in each branch to output electrical energy to the DC cabinet. It is measured using a DC ammeter. The average branch output current FD is the arithmetic mean of the output currents of all branches of the DC cabinet, in amperes. The method of obtaining it is as follows: use a DC ammeter to obtain the output current values ​​of each branch of the DC cabinet at the same time, add these current values ​​and divide them by the number of branches to obtain the average branch output current FD. The rated power FE of the PV module refers to the maximum power that the PV module can output under standard test conditions, in watts, which is used to characterize the power generation capacity of the module. It is obtained by checking the module nameplate or technical specification. The standard test conditions are usually: the light intensity is 1000W / m 2 , the component temperature is 25℃ and the air mass is AM1.5.

[0114] According to the output voltage FA of each branch of the DC cabinet i , branch output voltage average FB, each branch output current FC i , average branch output current FD, PV module output power AA a The formula for calculating the photovoltaic power generation system index WD based on the rated power FE of the photovoltaic modules is:

[0115]

[0116] Among them, FA i is the output voltage of the i-th branch in the DC cabinet, i is the serial number corresponding to different branches, and its value is [1, m]; m is the total number of branches in the DC cabinet, and its value is a positive integer; FC i is the output current of the i-th branch in the DC cabinet.

[0117] It should be noted that the operating principle of this formula is: It is the average value of the sum of the absolute values ​​of the difference between the output power of each photovoltaic module and the rated power. It reflects the degree of deviation between the actual output power of the photovoltaic module and the rated power. If the deviation is small, it means that the module is operating in a relatively ideal state and can be close to its designed power generation capacity, which has a positive contribution to the system performance. The higher the photovoltaic power generation system index WD, It is the ratio of the sum of the absolute values ​​of the differences between the output voltages of each branch and the average value of the branch output voltage to the product of the number of branches and the average value of the branch output voltage. It is used to measure the discrete degree of the output voltage of each branch of the DC cabinet relative to the average value of the branch output voltage. It is the ratio of the sum of the absolute values ​​of the differences between the output current of each branch and the average value of the branch output current to the product of the number of branches and the average value of the branch output current. It reflects the discreteness of the output current of each branch of the DC cabinet relative to the average value of the branch output current. The discreteness of the output voltage and current of each branch of the DC cabinet is small, which means that the power transmission and distribution of each branch are relatively uniform, the stability and reliability of the system are high, and the photovoltaic power generation system index WD will also be high. On the contrary, if the discreteness is large, there may be problems such as branch faults and line impedance imbalance, which will affect the overall performance of the system, and the photovoltaic power generation system index WD will also be low. This formula uses the negative exponential form of the exponential function to comprehensively evaluate the state of the photovoltaic power generation system through three aspects: the deviation degree of the output power of the photovoltaic module from the rated power, the discreteness of the output voltage of each branch of the DC cabinet, and the discreteness of the output current of each branch of the DC cabinet, and obtains the photovoltaic power generation system index WD, where e is the base of the natural logarithm in the exponential function.

[0118] Step 206: The method for calculating the energy storage system state indicator WE is:

[0119] The energy storage system data also includes the initial charge state GA, the rated capacity of the battery pack GB, the battery pack charge and discharge current GC(t), the initial internal resistance of the battery pack GD and the current internal resistance of the battery pack GE.

[0120] It should be noted that the initial charge state GA refers to the ratio of the charge stored in the energy storage battery to the rated capacity of the battery pack, usually expressed as a percentage. It reflects the battery's charge status when it is not being charged or discharged or when it is just being used. It is one of the important parameters for the operation management and control of the energy storage system. It can be obtained by checking the initial settings of the battery management system or the charge status recorded during the last shutdown. The rated capacity of the battery pack GB refers to the amount of electricity that the battery pack can discharge under specified discharge conditions. It is usually measured in ampere-hours. It is an important performance indicator of the battery pack and represents the ability of the battery pack to store electrical energy. It can be obtained by checking the product manual or nameplate of the battery pack. The battery pack charge and discharge current GC(t) refers to the current flowing through the battery pack during the charge and discharge process. It is a quantity that changes with time and is measured in amperes. When GC(t) is positive, it means The battery pack is charging and current flows into the battery pack; when GC(t) is negative, it means that the battery pack is discharging and current flows out of the battery pack. It is obtained by real-time measurement using current sensors such as Hall current sensors and shunts. The initial internal resistance GD of the battery pack refers to the internal resistance of the battery pack when it is not charging or discharging or just starting to charge or discharge. The unit is ohm. It is measured when the battery pack is not charging or discharging using professional internal resistance testers such as UT677A+ battery internal resistance tester and RTBT-9000 intelligent battery internal resistance tester. The current internal resistance GE of the battery pack refers to the actual internal resistance of the battery pack at the current moment. The unit is ohm, which reflects the change in the internal resistance of the battery under the current working state. It is measured using professional internal resistance testers such as UT677A+ battery internal resistance tester and RTBT-9000 intelligent battery internal resistance tester.

[0121] The energy storage system status indicator WE is calculated based on the initial charge state GA, the rated capacity of the battery pack GB, the battery pack charge and discharge current GC(t), the initial internal resistance of the battery pack GD and the current internal resistance of the battery pack GE. The formula is as follows:

[0122]

[0123] Among them, GC(t) is the charge and discharge current of the battery pack at time point t, t is the sequence number corresponding to different time points, and t1 is the duration of the detection cycle.

[0124] It should be noted that the operating principle of this formula is: is to convert the integral of the current over time into a dimension comparable to the initial charge state, It is the amount of charge charged or discharged from the battery pack from the initial time to the current time. It is used to measure the degree of change of the battery's charge and discharge capacity from the initial state during this period. It is used to measure the aging degree of the internal resistance of the battery pack. The lower the value, the higher the aging degree and the worse the energy storage effect. This formula obtains the energy storage system status index WE by taking the square root of the sum of the two indicators and comprehensively considering the influence of the above two aspects.

[0125] Step 207: The method for calculating the power equipment operating status index X is:

[0126] The power equipment operation status index X is calculated based on the photovoltaic power generation-energy storage system coordination efficiency index WA, the transmission line stability index WB, the photovoltaic power generation-inverter coordination index WC, the photovoltaic power generation system index WD and the energy storage system status index WE. The formula is as follows:

[0127]

[0128] It should be noted that this formula is based on the concept of geometric mean, comprehensively considering the influence of photovoltaic power generation-energy storage system synergy efficiency index WA, transmission line stability index WB, photovoltaic power generation-inverter synergy index WC, photovoltaic power generation system index WD and energy storage system status index WE, emphasizing the balance and synergy between various indicators, and finally obtaining the power equipment operation status index X.

[0129] Combined with the contents of step 201 to step 207:

[0130] The photovoltaic power generation-energy storage system synergy efficiency index WA is calculated based on the photovoltaic power generation system data, energy storage system data and overall data. It can accurately measure the synergy between the photovoltaic power generation system and the energy storage system in actual operation, which is helpful to determine the optimal configuration ratio of the photovoltaic power generation system and the energy storage system. The transmission line stability index WB is calculated based on the inverter and grid-connected system data and the transmission line data. It can not only reflect the status of the transmission line itself, but also reflect the impact of the inverter and grid-connected system on the transmission stability. It can fully grasp the various factors in the transmission process and help to discover potential system weaknesses. The photovoltaic power generation-inverter synergy index WC is calculated based on the photovoltaic power generation system data and the inverter and grid-connected system data. It comprehensively considers the data of the two key links of photovoltaic power generation and inverter grid connection, and can comprehensively evaluate the efficiency of the entire power generation and grid connection process. It can intuitively show whether the two can cooperate efficiently under different working conditions, providing a key reference for evaluating the overall performance of the system. The power system index WD can reflect the operating status of the photovoltaic power generation system in real time, understand the power generation level of the system under different lighting conditions, and evaluate whether it meets the design requirements and expected goals. The energy storage system status index WE is calculated based on the energy storage system data, which can understand the energy storage level of the energy storage system and the loss during the energy conversion process, providing a reference for optimizing system operation. The power equipment operating status index X is calculated based on the photovoltaic power generation-energy storage system collaborative efficiency index WA, the transmission line stability index WB, the photovoltaic power generation-inverter collaborative index WC, the photovoltaic power generation system index WD and the energy storage system status index WE, which is conducive to a comprehensive analysis of the overall operating status of the equipment, avoiding misjudgment or missed judgment caused by a single indicator judgment, and solving the problem that traditional monitoring systems often only focus on the operating status of a single device, ignoring the collaborative working relationship between different devices and various systems, resulting in an inability to comprehensively evaluate the operating status of the entire photovoltaic storage project and difficult to timely discover systemic potential problems.

[0131] Step 3: Preset an operating status threshold set; determine the operating status of the power equipment according to the power equipment operating status indicator X and the operating status threshold set, and select an early warning method according to the operating status of the power equipment.

[0132] Step 3 includes the following steps:

[0133] Step 301: The method for determining the operating status of the power equipment is:

[0134] The operating state threshold set includes a normal operating state threshold YC, a medium risk threshold YZ and a high risk threshold YG.

[0135] It should be noted that the method for determining the normal operating status threshold YC, the medium-risk threshold YZ and the high-risk threshold YG is: collect data on the normal operating status of the photovoltaic storage project at different periods, and calculate the power equipment operating status index data at different periods according to the above method, further calculate the mean and standard deviation of the power equipment operating status index data, calculate the value of the mean value minus one times the standard deviation, as the reference value of the normal operating status threshold YC, calculate the value of the mean value plus one times the standard deviation, as the reference value of the medium-risk threshold YZ, and calculate the value of the mean value plus two times the standard deviation as the reference value of the high-risk threshold YG.

[0136] The operating state of the power equipment is judged according to the power equipment operating state index X and the operating state threshold set, and the standard is as follows:

[0137]

[0138] When it is in normal operation, select warning method one, specifically: set indicator lights of different colors to indicate the system status in the control center or equipment panel of the photovoltaic storage project. When the system is operating normally, the indicator light is green. At the same time, various operating parameters of the power equipment are continuously collected through sensors and intelligent monitoring systems, and emails are regularly sent to the operation and maintenance personnel and relevant persons in charge to report the system's operating status. When the system encounters some situations that do not affect normal operation but require attention, such as an increase in the loss rate of a certain equipment, an email will be sent immediately to notify the operation and maintenance personnel and relevant persons in charge.

[0139] When it is in a low-risk operating state, select warning method 2, specifically: when it is in a low-risk operating state, the indicator light is yellow. At the same time, the monitoring system automatically sends a text message to the operation and maintenance personnel's mobile phone to inform them that the system is in a low-risk operating state and the relevant parameters and specific problems that cause risks.

[0140] When the operating state is medium-risk, select warning method three, specifically: when the operating state is medium-risk, the indicator light is red, and real-time attention is paid to the key parameters of the equipment or system with medium risk. At the same time, text messages and emails are sent to the operation and maintenance personnel and relevant persons in charge to inform them of the detailed information of the medium risk. In addition to risk descriptions and parameter data, the emails and text messages should also be accompanied by historical handling experience and reference plans of similar cases to provide decision support for the operation and maintenance personnel.

[0141] When the operating state is high-risk, select early warning method four, specifically: once the monitoring system detects that the operating state is high-risk, the sound alarm is triggered immediately, the indicator light turns orange, and an emergency notification is sent to the relevant responsible persons through multiple communication channels such as SMS, phone, email or dedicated application notifications. At the same time, the monitoring frequency of key indicators is increased to ensure that the development trend of abnormal situations can be captured more frequently. When the abnormal situation continues to develop, the operation is stopped.

[0142] Combined with the content of step 301:

[0143] Judging the operating status of power equipment based on the power equipment operating status indicator X and the operating status threshold set can reflect the equipment status in real time and provide accurate equipment operating information for operation and maintenance personnel. Selecting early warning methods based on the operating status of power equipment is conducive to discovering potential problems and hidden faults of equipment in advance, avoiding the occurrence of equipment failures, and ensuring stable operation of equipment.

[0144] On the other hand, the present invention also discloses a high-altitude power equipment condition monitoring system, which is used to implement the above-mentioned high-altitude power equipment condition monitoring method, comprising:

[0145] Data acquisition module, used to collect photovoltaic power generation system data, energy storage system data, overall data, inverter and grid-connected system data and transmission line data of the photovoltaic storage project;

[0146] The index calculation module can calculate the photovoltaic power generation-energy storage system coordination efficiency index WA based on the photovoltaic power generation system data, the energy storage system data and the overall data; calculate the transmission line stability index WB based on the inverter and grid-connected system data and the transmission line data; calculate the power transmission consistency index QA based on the inverter and grid-connected system data, and calculate the photovoltaic power generation-inverter coordination index WC according to the power transmission consistency index QA, the photovoltaic power generation system data and the inverter and grid-connected system data; calculate the photovoltaic power generation system index WD based on the photovoltaic power generation system data; calculate the energy storage system status index WE based on the energy storage system data; calculate the power equipment operation status index X according to the photovoltaic power generation-energy storage system coordination efficiency index WA, the transmission line stability index WB, the photovoltaic power generation-inverter coordination index WC, the photovoltaic power generation system index WD and the energy storage system status index WE;

[0147] The judgment module can preset an operation status threshold set; judge the operation status of the power equipment according to the power equipment operation status indicator X and the operation status threshold set, and select an early warning method according to the operation status of the power equipment.

[0148] The above embodiments may be implemented in whole or in part by software, hardware, firmware or any other combination thereof. When implemented using software, the above embodiments may be implemented in whole or in part in the form of a computer program product. A person of ordinary skill in the art may appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein may be implemented in electronic hardware or in combination with 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.

[0149] 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 solution of this embodiment.

[0150] The above description is only a specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application.

Claims

1. A method for monitoring the condition of high-altitude power equipment, characterized in that: The following steps are involved: Collect photovoltaic power generation system data, energy storage system data, overall data, inverter and grid-connected system data and transmission line data of the photovoltaic storage project; Calculate the photovoltaic power generation-energy storage system synergy efficiency index WA based on the photovoltaic power generation system data, energy storage system data and overall data; calculate the transmission line stability index WB based on the inverter and grid-connected system data and the transmission line data; calculate the power transmission consistency index QA based on the inverter and grid-connected system data, and calculate the photovoltaic power generation-inverter synergy index WC based on the power transmission consistency index QA, photovoltaic power generation system data and inverter and grid-connected system data; calculate the photovoltaic power generation system index WD based on the photovoltaic power generation system data; calculate the energy storage system status index WE based on the energy storage system data; calculate the power equipment operation status index X based on the photovoltaic power generation-energy storage system synergy efficiency index WA, the transmission line stability index WB, the photovoltaic power generation-inverter synergy index WC, the photovoltaic power generation system index WD and the energy storage system status index WE; A set of operating status thresholds is preset; the operating status of the power equipment is judged according to the operating status indicator X of the power equipment and the operating status threshold set, and an early warning method is selected according to the operating status of the power equipment.

2. A method for monitoring the condition of high-altitude power equipment according to claim 1, characterized in that: The method for calculating the synergistic efficiency index WA of the photovoltaic power generation-energy storage system is: Photovoltaic power generation system data includes photovoltaic module output power AA a and the starting time AE of the PV module power change; Energy storage system data includes energy storage system charging and discharging power AB a and the energy storage system starts responding at AF; The overall data includes the useful power AC to meet the load demand a ; The photovoltaic power generation-energy storage system synergy efficiency index WA is calculated based on the photovoltaic power generation system data, energy storage system data and overall data. The formula is: Among them, AA a is the output power of the photovoltaic module at the ath sampling time point, a is the serial number corresponding to different sampling time points, and its value is [1, b]; b is the total number of sampling time points, and its value is a positive integer; AB a is the charging or discharging power of the energy storage system at the ath sampling time point; AC a is the useful power that meets the load demand at the ath sampling time point.

3. A method for monitoring the condition of high-altitude power equipment according to claim 2, characterized in that: The method for calculating the transmission line stability index WB is: Inverter and grid-connected system data including inverter harmonic current RMS value BA d , fundamental current effective value BB and output current rated effective value BD; The transmission line data includes the transmission line resistance CA and the transmission line reactance CB; The transmission line stability index WB is calculated based on the inverter and grid-connected system data and the transmission line data, and the formula is: Among them, BA d is the effective value of the harmonic current of the dth harmonic, d is the serial number corresponding to different harmonics, and its value is [1, f]; f is the total number of harmonics, and its value is a positive integer.

4. A method for monitoring the condition of high-altitude power equipment according to claim 3, characterized in that: The method for calculating the power transmission consistency index QA is: Inverter and grid-connected system data also includes inverter input power DA a and inverter output power DB a ; According to the inverter input power DA a and inverter output power DB a The power transmission consistency indicator QA is calculated based on the formula: Among them, DA a is the input power of the inverter at the ath sampling time point; DB a is the output power of the inverter at the ath sampling time point.

5. A method for monitoring the condition of high-altitude power equipment according to claim 4, characterized in that: The method for calculating the photovoltaic power generation-inverter synergy index WC is: Photovoltaic power generation system data also includes output voltage frequency EA; The inverter and grid-connected system data also include grid frequency EB, grid rated frequency EC, inverter conversion efficiency ED and inverter conversion efficiency average EE; The photovoltaic power generation-inverter synergy index WC is calculated based on the power transmission consistency index QA, output voltage frequency EA, grid frequency EB, grid rated frequency EC, inverter conversion efficiency ED and inverter conversion efficiency average EE. The formula is: Among them, ɑ1 is the weight coefficient of the power transmission consistency index QA, which ranges from 0.3 to 0.5; ɑ2 is The weight coefficient is 0.2~0.5; ɑ3 is The weight coefficient is between 0.2 and 0.5, and ɑ1+ɑ2+ɑ3=1.

6. A method for monitoring the condition of high-altitude power equipment according to claim 5, characterized in that: The method for calculating the photovoltaic power generation system index WD is: Photovoltaic power generation system data also includes the output voltage FA of each branch of the DC cabinet i , branch output voltage average FB, each branch output current FC i , the average value of branch output current FD and the rated power FE of the PV module; According to the output voltage FA of each branch of the DC cabinet i , branch output voltage average FB, each branch output current FC i , average branch output current FD, PV module output power AA a The formula for calculating the photovoltaic power generation system index WD based on the rated power FE of the photovoltaic modules is: Among them, FA i is the output voltage of the i-th branch in the DC cabinet, i is the serial number corresponding to different branches, and its value is [1, m]; m is the total number of branches in the DC cabinet, and its value is a positive integer; FC i is the output current of the i-th branch in the DC cabinet.

7. A method for monitoring the condition of high-altitude power equipment according to claim 6, characterized in that: The method for calculating the energy storage system state index WE is: The energy storage system data also includes the initial charge state GA, the rated capacity of the battery pack GB, the battery pack charge and discharge current GC(t), the initial internal resistance of the battery pack GD and the current internal resistance of the battery pack GE; The energy storage system status indicator WE is calculated based on the initial charge state GA, the rated capacity of the battery pack GB, the battery pack charge and discharge current GC(t), the initial internal resistance of the battery pack GD and the current internal resistance of the battery pack GE. The formula is as follows: Among them, GC(t) is the charge and discharge current of the battery pack at time point t, t is the sequence number corresponding to different time points, and t1 is the duration of the detection cycle.

8. A method for monitoring the condition of high-altitude power equipment according to claim 7, characterized in that: The method for calculating the power equipment operating status index X is: The power equipment operation status index X is calculated based on the photovoltaic power generation-energy storage system coordination efficiency index WA, the transmission line stability index WB, the photovoltaic power generation-inverter coordination index WC, the photovoltaic power generation system index WD and the energy storage system status index WE. The formula is as follows:

9. A method for monitoring the condition of high-altitude power equipment according to claim 8, characterized in that: The method to judge the operating status of power equipment is: The operating state threshold set includes a normal operating state threshold YC, a medium risk threshold YZ, and a high risk threshold YG; The operating state of the power equipment is judged according to the power equipment operating state index X and the operating state threshold set, and the standard is as follows: When it is in normal operation, select early warning mode 1; When the operation is in a low-risk state, select early warning method 2; When the operating state is medium risk, select early warning method three; When the operating state is high risk, select warning method four.

10. A high altitude power equipment condition monitoring system, characterized in that: include: Data acquisition module, used to collect photovoltaic power generation system data, energy storage system data, overall data, inverter and grid-connected system data and transmission line data of the photovoltaic storage project; The index calculation module can calculate the photovoltaic power generation-energy storage system coordination efficiency index WA based on the photovoltaic power generation system data, the energy storage system data and the overall data; calculate the transmission line stability index WB based on the inverter and grid-connected system data and the transmission line data; calculate the power transmission consistency index QA based on the inverter and grid-connected system data, and calculate the photovoltaic power generation-inverter coordination index WC according to the power transmission consistency index QA, the photovoltaic power generation system data and the inverter and grid-connected system data; calculate the photovoltaic power generation system index WD based on the photovoltaic power generation system data; calculate the energy storage system status index WE based on the energy storage system data; calculate the power equipment operation status index X according to the photovoltaic power generation-energy storage system coordination efficiency index WA, the transmission line stability index WB, the photovoltaic power generation-inverter coordination index WC, the photovoltaic power generation system index WD and the energy storage system status index WE; The judgment module can preset an operation status threshold set; judge the operation status of the power equipment according to the power equipment operation status indicator X and the operation status threshold set, and select an early warning method according to the operation status of the power equipment.

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