Power supply current sharing control system

Abstract

The invention relates to a power supply current-sharing control technology, is used for solving the problem that an existing current-sharing control system can only carry out simple fault alarm and is difficult to quickly and accurately position fault causes, and particularly relates to a power supply current-sharing control system which comprises a data detection module, an abnormity judgment module, a fault diagnosis module and a control adjustment module. Current and voltage data are collected through the data detection module, and the load current and voltage data are obtained more accurately through abnormal value screening; the abnormity judgment module can timely find current sharing abnormity based on accurate data comparison, and for the condition of uneven load distribution, the control adjustment module can accurately adjust the duty ratio of a current control signal output by the power supply module according to the relation among the inductive current average value, the duty ratio and the inductive current peak value, so that the load current of each module tends to be balanced, and the load distribution efficiency is improved. The current sharing precision is effectively improved, overload or insufficient utilization of part of power modules is avoided, the overall efficiency of a power system is improved, and the service life of equipment is prolonged.

Description

Technical Field

[0001] The invention relates to a power supply current sharing control technology, in particular to a power supply current sharing control system. Background Art

[0002] In modern power systems, as various electrical equipment has increasingly higher requirements for power supply reliability and stability, power current equalization control technology has become a key link in ensuring the quality of power supply. The parallel power supply method of multiple power modules has been widely used in industrial production, communication base stations, data centers, and other fields because it can improve the power capacity of the power supply system, enhance redundancy and reliability; In terms of current sharing accuracy, the traditional current sharing control method mainly distributes the load current based on the droop characteristics of the power module output voltage as the current changes. This method is greatly affected by factors such as the difference in output impedance of the power module and the inconsistency of line impedance, resulting in low current sharing accuracy. In some occasions with extremely high requirements for power supply quality, such current sharing accuracy may cause some power modules to be overloaded, while some modules fail to fully function, which not only reduces the overall efficiency of the power system, but also affects the normal operation of the equipment and shortens the service life of the equipment. In terms of fault diagnosis and processing, the existing technology can usually only perform simple fault alarms when abnormal current sharing control occurs, and it is difficult to quickly and accurately locate the cause of the fault, which requires maintenance personnel to spend a lot of time and energy in troubleshooting, reducing the system availability and maintenance efficiency; In view of the above technical problems, this application proposes a solution. Summary of the invention

[0003] The purpose of the present invention is to collect current and voltage data through a data detection module, and obtain load current and voltage data more accurately after filtering out abnormal values; the abnormal judgment module can detect current sharing abnormalities in time based on accurate data comparison. For uneven load distribution, the control adjustment module can accurately adjust the duty cycle of the output current control signal of the power module according to the relationship between the average value of the inductor current and the duty cycle and the peak value of the inductor current, so that the load current of each module tends to be balanced, effectively improve the current sharing accuracy, avoid overloading or underutilization of some power modules, improve the overall efficiency of the power supply system, extend the service life of the equipment, and solve the problem that the existing current sharing control system can only perform simple fault alarms and it is difficult to quickly and accurately locate the cause of the fault, and propose a power current sharing control system.

[0004] The purpose of the present invention can be achieved through the following technical solutions: A power supply current sharing control system, comprising a data detection module, an abnormality determination module, a fault diagnosis module and a control adjustment module; The data detection module collects the current data passing through the power supply and the voltage data at both ends of the power supply, and after filtering out abnormal values, transmits the detected current data and voltage data to the abnormality determination module; The abnormality determination module compares the load current data of each power module with the load current average. If the absolute value of the difference between the two is greater than the preset current change threshold, it is determined that the current sharing control is abnormal and the abnormal power module is determined; The fault diagnosis module obtains the load current data of the abnormal power module processed by the abnormality determination module, compares the load current data with the rated current data, determines the abnormal situation according to the comparison result, and transmits the processing result to the control adjustment module; The control and adjustment module receives the processing results transmitted by the fault diagnosis module and performs precise control and adjustment on the power module according to the processing results.

[0005] As a preferred embodiment of the present invention, the processing steps of the data detection module to screen out abnormal values ​​are as follows: K1: Calculate the corresponding mean and standard deviation of the load current data and voltage data detected at the same time, and then use the calculated mean and standard deviation data to establish the fluctuation range of the load current and voltage respectively. The difference between the load current mean and twice the load current standard deviation is recorded as the lower limit of the load current fluctuation range, and the sum of the load current mean and twice the load current standard deviation is recorded as the upper limit of the load current fluctuation range, so as to obtain the fluctuation range of the load current; the difference between the voltage mean and twice the voltage standard deviation is recorded as the lower limit of the voltage fluctuation range, and the sum of the voltage mean and twice the voltage standard deviation is recorded as the upper limit of the voltage fluctuation range, so as to obtain the fluctuation range of the voltage; K2: The load current data and voltage data that are not within the corresponding fluctuation range are marked as abnormal load current data and abnormal voltage data. After the abnormal load current data and abnormal voltage data in the detection data are eliminated, the mean of the remaining load current data and voltage data are calculated respectively, and the calculated load current mean and voltage mean are recorded as the load current data and voltage data at the corresponding moment.

[0006] As a preferred embodiment of the present invention, the abnormality determination steps of the abnormality determination module are as follows: M1: When multiple power modules supply power to the load, the load current data of each power module is detected, and the average load current corresponding to each power module is calculated; M2: If the absolute value of the difference between the load current data of the corresponding power module and the load current average is greater than the preset current change threshold, it is determined that there is an abnormality in the current sharing control, and the power module whose absolute value of the difference between the load current data and the load current average is greater than the preset current change threshold is determined as an abnormal power module.

[0007] As a preferred embodiment of the present invention, the abnormal situation determination steps of the fault diagnosis module are as follows: Q1: Compare the load current data of the abnormal power module with the rated current data of the power module. If the load current data of the abnormal power module is less than the rated current data, it is determined that there is uneven load distribution, power module failure or load change; if the load current data of the abnormal power module is greater than the rated current data, it is determined that there is overload, power module failure or short circuit. Q2: If the number of parallel power modules is , the number of power modules whose absolute value of the difference between the load current data and the load current mean is equal to the preset current change threshold is counted and recorded as , then the number of power modules with large deviation between load current data and load current mean is , if the preset comparison threshold , it is determined that the abnormal current sharing control is caused by uneven load distribution; Q3: Use an oscilloscope to detect the waveform and amplitude of the current sharing control signal, record the wavelength, wave width and amplitude data of the current sharing control signal, and compare the recorded wavelength, wave width and amplitude data of the current sharing control signal with the preset wavelength, wave width and amplitude data of the current sharing control signal. If the difference between the corresponding item data exceeds the preset fluctuation threshold, it is determined that the abnormal current sharing control is caused by uneven load distribution; Q4: If both methods determine that the current sharing control system has uneven load distribution, it is determined that the abnormal current sharing control is caused by uneven load distribution; otherwise, the uneven load distribution detection is performed again.

[0008] As a preferred embodiment of the present invention, the fault diagnosis module performs the following steps to determine the power module fault and load change: S1: Test the abnormal power module, measure the output voltage data and output current data of the abnormal power module under different input conditions, and draw the output voltage and output current curves in the coordinate system constructed by the output voltage and output current, which are recorded as abnormal curves, and then draw the output voltage and output current curves of the normal power module in the coordinate system constructed by the output voltage and output current, which are recorded as normal curves; S2: intercept a coordinate segment of a set length on the coordinate system, take the end close to the coordinate origin as the starting segment of the coordinate segment, take a point of the starting segment as the starting point, and the point of the corresponding value on the horizontal axis of the coordinate as the end point. Draw a connecting line and calculate the slope of the connecting line. If the value difference on the vertical axis of the coordinate corresponding to the end point is within the set fluctuation range, and the slope of the connecting line corresponding to the abnormal curve and the normal curve is within the set fluctuation range, it is determined that the abnormal power module is normal; otherwise, it is determined that the abnormal current sharing control is caused by a power module failure; S3: Detect the temperature data of the abnormal power module, and compare the detected temperature data of the abnormal module with the temperature data of the normal module. If the absolute value of the temperature difference is greater than a preset temperature threshold, it is determined that the abnormal current sharing control is caused by a power module failure. S4: If both methods determine that the abnormal power module is faulty, it is determined that the abnormal current sharing control is caused by the power module fault; otherwise, the abnormal power module fault is detected again.

[0009] As a preferred embodiment of the present invention, the fault diagnosis module performs the following steps to determine overload and short circuit: R1: Calculate the rated power data of the load device based on the detection voltage data and detection current data of the load device. , and then calculate the sum of the rated powers of several power modules supplying power to the load device. If the actual power of the load device is greater than the sum of the rated powers of the power modules, it is determined that the abnormal current sharing control is caused by overload; R2: If the load rate of the load device exceeds If the ratio of , the load device is determined to be in a high-load working state. If the load device is in a high-load working state and the load current of the power module exceeds the rated value, it is determined that the abnormal current sharing control is caused by overload. R3: If the measured resistance is zero, it is determined that the abnormal current sharing control is caused by a short circuit.

[0010] As a preferred embodiment of the present invention, the adjustment steps of the control adjustment module are as follows: Y1: If it is determined that the abnormal current sharing control is caused by uneven load distribution, the duty cycle of the output current control signal of the power module is adjusted to change its output power so that the load current of each module tends to be balanced; suppose the duty cycle of the current control signal is , the peak value of the inductor current of the power module is , the average value of the inductor current The relationship between the duty cycle and the peak inductor current is expressed as , when the load current needs to be adjusted, the duty cycle before adjustment is , the corresponding load current is , the adjusted duty cycle is , the corresponding load current is ,but , , compared with the two formulas, we can deduce ; Y2: If it is determined that the abnormal current sharing control is caused by a power module failure, the system immediately cuts off the connection between the faulty module and the load, and issues an alarm to notify maintenance personnel to repair or replace it; if it is determined that the abnormal current sharing control is caused by an overload, the system communicates with the load device to request the load device to reduce the power demand, or directly cuts off the power supply to some non-critical loads; if it is determined that the abnormal current sharing control is caused by a short circuit, the system immediately cuts off the output of the power module; Y3: If it is determined that the abnormal current sharing control is caused by load changes, the system automatically adjusts the output current of each power module according to the real-time changes of load current and voltage; for a time series ,in n represents the time point, Indicates at a point in time The load value, a Order autoregressive model Expressed as , is the autoregressive coefficient, is a white noise sequence, representing the random error of the model; by analyzing the historical load data Use the least squares method and other methods to estimate the parameters and obtain the autoregressive coefficients Estimated value of , then at time point Load forecast value Expressed as ; Y4: No. The power module at time The output power is , the total output power of all power modules , the ideal power share that each power module should bear , For the The rated power of each power module, For the The rated power of each power module; based on the load prediction value Calculate at time point At this moment, the output power of each power module should be adjusted to ; at a point in time At this moment, the total output power target value that all power modules should achieve is , the power factor of the load is ,but ;No. The power module at time Target output power , then The power module at time The output power should be adjusted .

[0011] Compared with the prior art, the present invention has the following beneficial effects: 1. The data detection module collects current and voltage data, and after filtering out abnormal values, the load current and voltage data can be obtained more accurately. The abnormality judgment module can detect current sharing abnormalities in a timely manner based on accurate data comparison. For uneven load distribution, the control adjustment module can accurately adjust the duty cycle of the output current control signal of the power module according to the relationship between the average value of the inductor current and the duty cycle and the peak value of the inductor current, so that the load current of each module tends to be balanced, effectively improving the current sharing accuracy, avoiding overload or underutilization of some power modules, improving the overall efficiency of the power system, and extending the service life of the equipment; 2. The fault diagnosis module compares the load current of the abnormal power module with the rated current, and combines the number of parallel power modules and the current sharing control signal analysis to accurately determine the problem of uneven load distribution; by testing the output characteristics of the abnormal module, detecting the temperature and comparing it with the normal module, the power module fault can be effectively diagnosed; by using methods such as changes in the working status of the load equipment and power calculation, the abnormal conditions of load changes, overloads and short circuits can be identified; for different faults, the control and adjustment module can take targeted measures, such as cutting off the connection of the faulty module, requesting the load equipment to reduce power, cutting off the power supply of non-critical loads, adjusting the output of the power module, etc., which greatly improves the fault handling efficiency and system availability. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to facilitate understanding by those skilled in the art, the present invention is further described below with reference to the accompanying drawings.

[0013] Figure 1 It is a system flow chart of the present invention. DETAILED DESCRIPTION

[0014] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than 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. Example

[0015] See also Figure 1 As shown, a power supply current sharing control system includes a data detection module, an abnormality determination module, a fault diagnosis module and a control adjustment module; Detect the current data passing through the power supply and the voltage data at both ends of the power supply, record the load current data and voltage data detected at the same time, and filter out abnormal values; The corresponding mean and standard deviation of the load current data and voltage data detected at the same time are calculated respectively, and then the fluctuation ranges of the load current and voltage are established respectively with the calculated mean and standard deviation data, and the difference between the load current mean and twice the load current standard deviation is recorded as the lower limit of the load current fluctuation range, and the sum of the load current mean and twice the load current standard deviation is recorded as the upper limit of the load current fluctuation range, so as to obtain the fluctuation range of the load current; the difference between the voltage mean and twice the voltage standard deviation is recorded as the lower limit of the voltage fluctuation range, and the sum of the voltage mean and twice the voltage standard deviation is recorded as the upper limit of the voltage fluctuation range, so as to obtain the voltage fluctuation range; the load current data and voltage data that are not within the corresponding fluctuation range are marked as abnormal load current data and abnormal voltage data, and after the abnormal load current data and abnormal voltage data in the detection data are eliminated, the mean of the remaining load current data and voltage data is calculated respectively, and the calculated load current mean and voltage mean are recorded as the load current data and voltage data at the corresponding moment.

[0016] When multiple power modules supply power to the load, the load current data of each power module is detected, and the load current average corresponding to each power module is calculated. If the absolute value of the difference between the load current data of the corresponding power module and the load current average is greater than the preset current change threshold, it is determined that there is an abnormality in the current sharing control, and the power module whose absolute value of the difference between the load current data and the load current average is greater than the preset current change threshold is determined as an abnormal power module; The load current data of the abnormal power module is compared with the rated current data corresponding to the power module. If the load current data of the abnormal power module is smaller than the rated current data, it is determined that there is uneven load distribution, power module failure or load change; if the load current data of the abnormal power module is larger than the rated current data, it is determined that there is overload, power module failure or short circuit.

[0017] If the number of parallel power modules is , the number of power modules whose absolute value of the difference between the load current data and the load current mean is equal to the preset current change threshold is counted and recorded as , then the number of power modules with large deviation between load current data and load current mean is , if the preset comparison threshold , it is determined that the abnormal current sharing control is caused by uneven load distribution; the waveform and amplitude of the current sharing control signal are detected by an oscilloscope, the wavelength, wave width and amplitude data of the current sharing control signal are recorded, and the wavelength, wave width and amplitude data of the recorded current sharing control signal are compared with the preset wavelength, wave width and amplitude data of the current sharing control signal. If the difference between the corresponding item data exceeds the preset fluctuation threshold, it is determined that the abnormal current sharing control is caused by uneven load distribution; if both methods determine that the current sharing control system has uneven load distribution, it is determined that the abnormal current sharing control is caused by uneven load distribution; otherwise, the uneven load distribution detection is performed again; The abnormal power module is tested, the output voltage data and output current data of the abnormal power module under different input conditions are measured, and the output voltage and output current curves are plotted in the coordinate system constructed by the output voltage and the output current, which are recorded as abnormal curves. Then, the output voltage and output current curves of the normal power module are plotted in the coordinate system constructed by the output voltage and the output current, which are recorded as normal curves. A coordinate segment of a set length is intercepted on the coordinate system, and the end close to the origin of the coordinate is taken as the starting segment of the coordinate segment, and a point of the starting segment is taken as the starting point, and the point corresponding to the value on the horizontal axis of the coordinate is taken as the end point. A connecting line is drawn and the slope of the connecting line is calculated. If the coordinate vertical axis corresponding to the end point is If the numerical difference on the axis is within the set fluctuation range, and the slope of the corresponding connecting line between the abnormal curve and the normal curve is within the set fluctuation range, the abnormal power module is judged to be normal; otherwise, the abnormal current sharing control is judged to be caused by the power module failure; the temperature data of the abnormal power module is detected, and the difference between the detected abnormal module temperature data and the normal module temperature data is compared. If the absolute value of the temperature difference is greater than the preset temperature threshold, the abnormal current sharing control is judged to be caused by the power module failure; if both methods determine that the abnormal power module is faulty, it is determined that the abnormal current sharing control is caused by the power module failure; otherwise, the abnormal power module failure is re-detected; Obtain the working status change of the load device. When the load device operates, mark the time when the operation occurs. If the time point when the load current changes coincides with the time point when the load device operates, it is determined that the abnormal current sharing control is caused by the load change.

[0018] The rated power data of the load device is calculated based on the detection voltage data and detection current data of the load device. , and then calculate the sum of the rated powers of several power modules supplying power to the load device. If the actual power of the load device is greater than the sum of the rated powers of the power modules, it is determined that the abnormal current sharing control is caused by overload; if the load rate of the load device exceeds If the ratio of , the load device is determined to be in a high-load working state. If the load device is in a high-load working state and the load current of the power module exceeds the rated value, it is determined that the abnormal current sharing control is caused by overload. Measure the input resistance of the load through the resistance range of the multimeter. If the measured resistance is zero, it is determined that the abnormal current sharing control is caused by a short circuit. Starting from the input end of the load, gradually disconnect the connections of each part. After disconnecting each part, re-measure the resistance of the input end. If the resistance value changes from close to zero to a normal value during the measurement process, it means that the short circuit occurs in the part that has just been disconnected. If it is determined that the abnormal current sharing control is caused by uneven load distribution, the duty cycle of the output current control signal of the power module is adjusted to change its output power so that the load current of each module tends to be balanced; suppose the duty cycle of the current control signal is , the peak value of the inductor current of the power module is , the average value of the inductor current The relationship between the duty cycle and the peak inductor current is expressed as , when the load current needs to be adjusted, the duty cycle before adjustment is , the corresponding load current is , the adjusted duty cycle is , the corresponding load current is ,but , , compared with the two formulas, we can deduce ; If it is determined that the abnormal current sharing control is caused by a power module failure, the system will immediately cut off the connection between the faulty module and the load, and send out an alarm to notify maintenance personnel to repair or replace it. During the troubleshooting process, the system will further analyze the operating data of the faulty module, and more accurately locate the fault point based on the circuit structure and component parameters inside the module, thereby improving maintenance efficiency. For faults that can be repaired online, such as software faults or drift of some hardware parameters, the system will attempt to automatically repair them and restore the normal operation of the module. If it is determined that the abnormal current sharing control is caused by load changes, the system automatically adjusts the output current of each power module according to the real-time changes of the load current and voltage to ensure that a good current sharing effect is always maintained during the load change process; at the same time, the system adjusts the output of the power module in advance by analyzing the historical operation data and operation mode of the load equipment to reduce the current sharing fluctuation caused by load changes; for a time series ,in n represents the time point, Indicates at a point in time The load value, a Order autoregressive model Expressed as , is the autoregressive coefficient, is a white noise sequence, representing the random error of the model; by analyzing the historical load data By using the least squares method and other methods to estimate parameters, we can get the autoregressive coefficients Estimated value of , then at time point Load forecast value Expressed as ; No. The power module at time The output power is , the total output power of all power modules In order to achieve current sharing control, the ideal power share that each power module should bear is , For the The rated power of each power module, For the The rated power of each power module; based on the load prediction value Calculate at time point At this moment, the output power of each power module should be adjusted to ; at a point in time At this moment, the total output power target value that all power modules should achieve is , the power factor of the load is ,but ;No. The power module at time Target output power , then The power module at time The output power should be adjusted ; If it is determined that the abnormal current sharing control is caused by overload, the system will communicate with the load device to request the load device to reduce the power demand, or directly cut off the power supply of some non-critical loads to take load reduction measures to protect the power module and load devices; at the same time, the system can monitor the operating status of the power module in real time. If the overload situation persists and cannot be solved by load reduction, an alarm should be issued in time to notify relevant personnel to handle it; If it is determined that the abnormal current sharing control is caused by a short circuit, the system will immediately cut off the output of the power module to prevent excessive short-circuit current from damaging the equipment; then, the short circuit location will be accurately determined through step-by-step investigation; after the short circuit fault is repaired, multiple short-circuit detection points will be set at key circuit nodes to improve the reliability of short-circuit detection.

[0019] The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to only specific implementation methods. Obviously, many modifications and changes can be made according to the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can understand and use the present invention well. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A power current sharing control system, characterized in that: It includes a data detection module, an abnormality determination module, a fault diagnosis module and a control adjustment module; The data detection module collects the current data passing through the power supply and the voltage data at both ends of the power supply, and after filtering out abnormal values, transmits the detected current data and voltage data to the abnormality determination module; The abnormality determination module compares the load current data of each power module with the load current average. If the absolute value of the difference between the two is greater than the preset current change threshold, it is determined that the current sharing control is abnormal and the abnormal power module is determined; The fault diagnosis module obtains the load current data of the abnormal power module processed by the abnormality determination module, compares the load current data with the rated current data, determines the abnormal situation according to the comparison result, and transmits the processing result to the control adjustment module; The control and adjustment module receives the processing result transmitted by the fault diagnosis module and controls and adjusts the power module according to the processing result.

2. A power current sharing control system according to claim 1, characterized in that: The processing steps of the data detection module to filter out outliers are as follows: K1: Calculate the corresponding mean and standard deviation of the load current data and voltage data detected at the same time, and then use the calculated mean and standard deviation data to establish the fluctuation range of the load current and voltage respectively. The difference between the load current mean and twice the load current standard deviation is recorded as the lower limit of the load current fluctuation range, and the sum of the load current mean and twice the load current standard deviation is recorded as the upper limit of the load current fluctuation range, so as to obtain the fluctuation range of the load current; the difference between the voltage mean and twice the voltage standard deviation is recorded as the lower limit of the voltage fluctuation range, and the sum of the voltage mean and twice the voltage standard deviation is recorded as the upper limit of the voltage fluctuation range, so as to obtain the fluctuation range of the voltage; K2: The load current data and voltage data that are not within the corresponding fluctuation range are marked as abnormal load current data and abnormal voltage data. After the abnormal load current data and abnormal voltage data in the detection data are eliminated, the mean of the remaining load current data and voltage data are calculated respectively, and the calculated load current mean and voltage mean are recorded as the load current data and voltage data at the corresponding moment.

3. A power current sharing control system according to claim 2, characterized in that: The abnormality determination steps of the abnormality determination module are as follows: M1: When each power module supplies power to the load, the load current data of each power module is detected, and the average load current corresponding to each power module is calculated; M2: If the absolute value of the difference between the load current data of the corresponding power module and the load current average is greater than the preset current change threshold, it is determined that there is an abnormality in the current sharing control, and the power module whose absolute value of the difference between the load current data and the load current average is greater than the preset current change threshold is determined as an abnormal power module.

4. A power current sharing control system according to claim 3, characterized in that: The abnormal situation determination steps of the fault diagnosis module are as follows: Q1: Compare the load current data of the abnormal power module with the rated current data of the power module. If the load current data of the abnormal power module is less than the rated current data, it is determined that there is uneven load distribution, power module failure or load change; if the load current data of the abnormal power module is greater than the rated current data, it is determined that there is overload, power module failure or short circuit. Q2: If the number of parallel power modules is , the number of power modules whose absolute value of the difference between the load current data and the load current mean is equal to the preset current change threshold is counted and recorded as , then the number of power modules with large deviation between load current data and load current mean is , if the preset comparison threshold , it is determined that the abnormal current sharing control is caused by uneven load distribution; Q3: Use an oscilloscope to detect the waveform and amplitude of the current sharing control signal, record the wavelength, wave width and amplitude data of the current sharing control signal, and compare the recorded wavelength, wave width and amplitude data of the current sharing control signal with the preset wavelength, wave width and amplitude data of the current sharing control signal. If the difference between the corresponding item data exceeds the preset fluctuation threshold, it is determined that the abnormal current sharing control is caused by uneven load distribution; Q4: If both methods determine that the current sharing control system has uneven load distribution, it is determined that the abnormal current sharing control is caused by uneven load distribution; otherwise, the uneven load distribution detection is performed again.

5. A power current sharing control system according to claim 4, characterized in that: The fault diagnosis module determines power module faults and load changes in the following steps: S1: Test the abnormal power module, measure the output voltage data and output current data of the abnormal power module under different input conditions, and draw the output voltage and output current curves in the coordinate system constructed by the output voltage and output current, which are recorded as abnormal curves, and then draw the output voltage and output current curves of the normal power module in the coordinate system constructed by the output voltage and output current, which are recorded as normal curves; S2: intercept a coordinate segment of a set length on the coordinate system, take the end close to the coordinate origin as the starting segment of the coordinate segment, take a point of the starting segment as the starting point, and the point of the corresponding value on the horizontal axis of the coordinate as the end point. Draw a connecting line and calculate the slope of the connecting line. If the value difference on the vertical axis of the coordinate corresponding to the end point is within the set fluctuation range, and the slope of the connecting line corresponding to the abnormal curve and the normal curve is within the set fluctuation range, it is determined that the abnormal power module is normal; Otherwise, it is determined that the abnormal current sharing control is caused by a power module failure; S3: Detect the temperature data of the abnormal power module, and compare the detected temperature data of the abnormal module with the temperature data of the normal module. If the absolute value of the temperature difference is greater than a preset temperature threshold, it is determined that the abnormal current sharing control is caused by a power module failure. S4: If both methods determine that the abnormal power module is faulty, it is determined that the abnormal current sharing control is caused by the power module fault; otherwise, the abnormal power module fault is detected again.

6. A power current sharing control system according to claim 5, characterized in that: The fault diagnosis module determines overload and short circuit in the following steps: R1: Calculate the rated power data of the load device based on the detection voltage data and detection current data of the load device. , and then calculate the sum of the rated powers of several power modules supplying power to the load device. If the actual power of the load device is greater than the sum of the rated powers of the power modules, it is determined that the abnormal current sharing control is caused by overload; R2: If the load rate of the load device exceeds If the ratio of , the load device is determined to be in a high-load working state. If the load device is in a high-load working state and the load current of the power module exceeds the rated value, it is determined that the abnormal current sharing control is caused by overload. R3: If the measured resistance is zero, it is determined that the abnormal current sharing control is caused by a short circuit.

7. A power current sharing control system according to claim 6, characterized in that: The adjustment steps of the control adjustment module are as follows: Y1: If it is determined that the abnormal current sharing control is caused by uneven load distribution, the duty cycle of the output current control signal of the power module is adjusted to change its output power so that the load current of each module tends to be balanced; suppose the duty cycle of the current control signal is , the peak value of the inductor current of the power module is , the average value of the inductor current The relationship between the duty cycle and the peak inductor current is expressed as , when the load current needs to be adjusted, the duty cycle before adjustment is , the corresponding load current is , the adjusted duty cycle is , the corresponding load current is ,but , , compared with the two formulas, we can deduce ; Y2: If it is determined that the abnormal current sharing control is caused by a power module failure, the system immediately cuts off the connection between the faulty module and the load, and issues an alarm to notify maintenance personnel to repair or replace it; if it is determined that the abnormal current sharing control is caused by an overload, the system communicates with the load device to request the load device to reduce the power demand, or directly cuts off the power supply to some non-critical loads; if it is determined that the abnormal current sharing control is caused by a short circuit, the system immediately cuts off the output of the power module; Y3: If it is determined that the abnormal current sharing control is caused by load changes, the system automatically adjusts the output current of each power module according to the real-time changes of load current and voltage; for a time series ,in n represents the time point, Indicates at a point in time The load value, a Order autoregressive model Expressed as , is the autoregressive coefficient, is a white noise sequence, representing the random error of the model; by analyzing the historical load data Use the least squares method and other methods to estimate the parameters and obtain the autoregressive coefficients Estimated value of , then at time point Load forecast value Expressed as ; Y4: No. The power module at time The output power is , the total output power of all power modules , the ideal power share that each power module should bear , For the The rated power of each power module, For the The rated power of each power module; based on the load prediction value Calculate at time point At this moment, the output power of each power module should be adjusted to ; at a point in time At this moment, the total output power target value that all power modules should achieve is , the power factor of the load is ,but ;No. The power module at time Target output power , then The power module at time The output power should be adjusted .

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