A switching power supply fault diagnosis method and system

Abstract

The present invention relates to the field of temperature measurement technology, and in particular to a switching power supply fault diagnosis method and system, the method comprising: obtaining historical pulse current and historical temperature data of a switching power supply within a predetermined historical time period; smoothing the historical pulse current to obtain a smoothed rectangular pulse current; using historical temperature data and rectangular pulse current at different historical moments to determine the first desirability of historical temperature data at each historical moment; using initial temperature data at the initial moment of the switching power supply to determine the initial temperature threshold at the initial moment of the switching power supply; using the first desirability of historical temperature data at different historical moments, rectangular pulse currents at different historical moments, initial temperature thresholds and initial temperature data to determine the temperature protection threshold at the next moment of the initial moment; and performing over-temperature fault diagnosis on the switching power supply according to the temperature protection threshold at the next moment. In this way, the present invention improves the reliability and accuracy of the over-temperature protection mechanism of the switching power supply.

Description

Technical Field

[0001] The present invention relates to the technical field of temperature measurement, and in particular to a switching power supply fault diagnosis method and system. Background Art

[0002] A switching power supply is an energy conversion device that converts AC to DC. It converts the input AC power into a stable DC output through high-frequency switching action. Its working principle is to use the switch tube to switch quickly at a high frequency to generate a pulse signal, and then convert it into the required DC voltage through the rectification and filtering circuit. In the switching power supply, over-temperature protection is a crucial safety measure, because the switching power supply will generate a lot of heat when working at a high frequency. If this heat cannot be dissipated in time, it will cause the internal temperature of the switching power supply to rise, which may cause serious consequences such as component damage, performance degradation and even fire. Therefore, the over-temperature protection mechanism can effectively prevent equipment damage and failure due to component overheating, and determine the stability and safety of the switching power supply.

[0003] In some scenarios, the over-temperature protection mechanism of the switching power supply is to install a temperature sensor to monitor the temperature inside the switching power supply in real time, and set a fixed threshold value, and automatically shut down the switching power supply when the temperature of the switching power supply reaches the fixed threshold value. However, this method of using a fixed threshold value may cause unnecessary shutdown of the switching power supply due to its overly conservative setting, or the over-temperature protection mechanism may malfunction due to the normal heat generated by the switching power supply under different working conditions. As a result, the reliability and accuracy of the over-temperature protection mechanism of the switching power supply are low. Summary of the invention

[0004] In order to solve the technical problem of low reliability and accuracy of the over-temperature protection mechanism of the switching power supply, the purpose of the present invention is to provide a switching power supply fault diagnosis method and system, and the technical solution adopted is as follows:

[0005] In a first aspect, an embodiment of the present invention provides a method for diagnosing a fault of a switching power supply, comprising: obtaining historical pulse current and historical temperature data of the switching power supply within a predetermined historical time period; smoothing the historical pulse current within the predetermined historical time period to obtain a smoothed rectangular pulse current; determining the first desirability of the historical temperature data at each historical moment using the historical temperature data at different historical moments within the predetermined historical time period and the rectangular pulse current; determining the initial temperature threshold of the switching power supply at the initial moment using the initial temperature data at the initial moment; determining the temperature protection threshold at the next moment after the initial moment using the first desirability of the historical temperature data at different historical moments, the rectangular pulse current at different historical moments, the initial temperature threshold and the initial temperature data; and performing over-temperature fault diagnosis on the switching power supply according to the temperature protection threshold at the next moment.

[0006] Optionally, smoothing the historical pulse current within the predetermined historical time period to obtain a smoothed rectangular pulse current includes: selecting at least one time period from the predetermined historical time period; determining the probability that the historical pulse current within the time period belongs to a rectangular pulse peak based on the average value of the historical pulse current in the time period and the historical pulse current at each acquisition point in the time period; selecting a first target time period in which the probability of the rectangular pulse peak is greater than a first threshold, taking the average value of all historical pulse currents in the first target time period as the current value of the first target time period, and taking the current value of the time period in which the probability of the rectangular pulse peak is not greater than the first threshold as a predetermined value, to obtain a smoothed rectangular pulse current.

[0007] Optionally, using the historical temperature data of different historical moments within the predetermined historical time period and the rectangular pulse current to determine the first desirability of the historical temperature data at each historical moment includes: determining the first temperature data of the first historical moment and the second temperature data of at least one target historical moment around the first historical moment; determining the second target time period in which the first historical moment and the target historical moment are located, and the first number of intersections of the rectangular pulse current and the predetermined current value within the second target time period; determining the frequency-temperature proportional coefficient between the first temperature data and the second temperature data based on the first temperature data, the second temperature data and the first number; and determining the first desirability of the first temperature data based on the frequency-temperature proportional coefficient of each target historical moment.

[0008] Optionally, determining the frequency-temperature proportional coefficient between the first temperature data and the second temperature data based on the first temperature data, the second temperature data and the first quantity includes: calculating the absolute value of the first difference between the first temperature data and the second temperature data; and determining a first ratio of the first quantity to the first difference as the frequency-temperature proportional coefficient.

[0009] Optionally, determining the first desirability of the first temperature data based on the frequency-temperature proportional coefficient of each target historical moment includes: determining the average value of the frequency-temperature proportional coefficient between the first temperature data and the second temperature data of each target historical moment; respectively calculating the second difference between the frequency-temperature proportional coefficient between the first temperature data and the second temperature data of each target historical moment and the average value, and superimposing each of the second differences to obtain a first superimposed value; and performing inverse proportional normalization processing on the first superimposed value to obtain the first desirability.

[0010] Optionally, determining the initial temperature threshold of the switching power supply at the initial moment using the initial temperature data of the switching power supply at the initial moment includes: determining a first sum between the initial temperature data and an allowed floating value as the initial temperature threshold, and the allowed floating value is a first product of the initial temperature data and a preset percentage.

[0011] Optionally, determining the temperature protection threshold of the next moment after the initial moment using the first desirability of historical temperature data at different historical moments, the rectangular pulse current at different historical moments, the initial temperature threshold and the initial temperature data includes: selecting the target historical temperature data identical to the initial temperature data from the predetermined historical time period, and determining the target historical moment where the target historical temperature data identical to the initial temperature data is located; determining the second desirability based on the first desirability of the target historical temperature data, the rectangular pulse current in the first time period from the target historical moment to the next historical moment, and the rectangular pulse current in the second time period from the initial moment to the next moment, the second desirability being the desirability of the temperature difference between the target historical temperature data at the target historical moment and the historical temperature data at the next historical moment with respect to the initial temperature data at the initial moment and the temperature data at the next moment; determining the temperature protection threshold of the next moment after the initial moment using the second desirability, the initial temperature threshold, the target historical temperature data at the target historical moment, and the historical temperature data at the next historical moment after the target historical moment.

[0012] Optionally, determining the second desirability based on the first desirability of the target historical temperature data, the rectangular pulse current in the first time period from the target historical moment to the next historical moment, and the rectangular pulse current in the second time period from the initial moment to the next moment includes: determining the second number of intersections of the rectangular pulse current and the predetermined current value in the first time period from the target historical moment to the next historical moment of the target historical moment, and the third number of intersections of the rectangular pulse current and the predetermined current value in the second time period from the initial moment to the next moment; calculating the second sum between the first desirability of the target historical temperature data at the target historical moment and the first desirability of the historical temperature data at the next historical moment of the target historical moment; calculating the reciprocal of the absolute value of the third difference between the second number and the third number, and processing the reciprocal of the absolute value of the third difference using the maximum and minimum normalization function to obtain a normalized value; determining the second product of the second sum and the normalized value as the second desirability.

[0013] Optionally, determining the temperature protection threshold of the next moment after the initial moment using the second desirability, the initial temperature threshold, the target historical temperature data of the target historical moment, and the historical temperature data of the next historical moment after the target historical moment includes: calculating the second superposition value of the second desirability of the target historical temperature data of each target historical moment; calculating the second ratio of the second desirability of each target historical moment to the second superposition value, and the fourth difference between the target historical temperature data of each target historical moment and the historical temperature data of the next historical moment after the target historical moment; calculating the third product between each of the second ratios and each of the fourth differences, and superimposing each of the third products to obtain a third superposition value; determining the third sum between the third superposition value and the initial temperature threshold as the temperature protection threshold of the next moment after the initial moment.

[0014] In a second aspect, an embodiment of the present invention provides a switching power supply fault diagnosis system, comprising: a processor and a memory; wherein the memory is used to store a computer program that can be run on the processor; the processor is used to execute the program stored in the memory to implement the steps of the switching power supply fault diagnosis method mentioned in the first aspect.

[0015] The present invention has the following beneficial effects: firstly, the historical pulse current and the historical temperature data of the switching power supply within a predetermined historical time period are obtained; then, the historical pulse current within the predetermined historical time period is smoothed to obtain the smoothed rectangular pulse current; secondly, the historical temperature data at different historical moments within the predetermined historical time period and the rectangular pulse current are used to determine the first desirability of the historical temperature data at each of the historical moments; then, the initial temperature data at the initial moment of the switching power supply is used to determine the initial temperature threshold of the switching power supply at the initial moment; then, the first desirability of the historical temperature data at different historical moments, the rectangular pulse current at different historical moments, the initial temperature threshold and the initial temperature data are used to determine the temperature protection threshold at the next moment of the initial moment; finally, the switching power supply is diagnosed for over-temperature fault according to the temperature protection threshold at the next moment.

[0016] In this way, in the embodiment of the present invention, a dynamic temperature protection threshold is set for the over-temperature protection mechanism through the historical temperature data and historical pulse current of the switching power supply, and the dynamic temperature protection threshold is obtained after updating the initial temperature threshold of the previous moment. When the over-temperature fault diagnosis of the switching power supply is performed at the current moment, the temperature of the switching power supply at the current moment is monitored in real time, and it is compared with the updated temperature protection threshold, so as to achieve the purpose of over-temperature fault diagnosis. Therefore, the embodiment of the present invention reduces the number of false alarms and improves the reliability and accuracy of the over-temperature protection mechanism of the switching power supply by setting a dynamic temperature protection threshold to perform over-temperature fault diagnosis on the switching power supply. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions and advantages in the embodiments of the present invention or the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 A flow chart of a switching power supply fault diagnosis method provided by one embodiment of the present invention;

[0019] Figure 2 A schematic circuit diagram of a forward switching power supply provided by an embodiment of the present invention;

[0020] Figure 3 A schematic diagram of a curve showing changes of historical pulse current and historical temperature data over time provided by an embodiment of the present invention;

[0021] Figure 4 A schematic diagram of a smoothed rectangular pulse current provided by an embodiment of the present invention;

[0022] Figure 5 A schematic diagram of the structure of a switching power supply fault diagnosis system provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0023] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the following is a detailed description of a switching power supply fault diagnosis method and system proposed by the present invention, its specific implementation, structure, features and effects, in combination with the accompanying drawings and preferred embodiments. In the following description, different "one embodiment" or "another embodiment" does not necessarily refer to the same embodiment. In addition, specific features, structures or characteristics in one or more embodiments may be combined in any suitable form.

[0024] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

[0025] A specific scheme of a switching power supply fault diagnosis method and system provided by the present invention is described in detail below with reference to the accompanying drawings.

[0026] Embodiment 1:

[0027] See also Figure 1 , which shows a flow chart of a switching power supply fault diagnosis method provided by an embodiment of the present invention, including:

[0028] S101, obtaining historical pulse current and historical temperature data of a switching power supply within a predetermined time period.

[0029] Specifically, the switching power supply in the embodiment of the present invention may be a forward switching power supply, such as Figure 2 As shown, Figure 2 A schematic diagram of a circuit of a forward switching power supply provided by an embodiment of the present invention, Figure 2 The Hall sensor H in the output circuit is installed to monitor the current change of the switching power supply, and the temperature sensor is installed on Figure 2 It is located near the switching element N-MOS tube, resistor R15, etc., to monitor the temperature changes at the switch and load.

[0030] Furthermore, the predetermined time period can be determined based on actual conditions, and the embodiments of the present invention do not limit this. When acquiring the historical pulse current and historical temperature data of the switching power supply within a predetermined time period, first turn on the switching power supply, and then simulate different working states of the switching power supply, such as different load conditions and switching frequencies. Then, a Hall sensor and a temperature sensor are used to measure the pulse current and temperature data of the switching power supply under different working states as historical pulse current and historical temperature data. Among them, in the embodiments of the present invention, the acquisition frequency of the Hall sensor is set to 1000 Hz, and the acquisition frequency of the temperature sensor is set to 1 Hz. For example, Figure 3 As shown, Figure 3 A schematic diagram of a curve showing changes of historical pulse current and historical temperature data over time provided by an embodiment of the present invention, Figure 3 In the process, as time changes, the pulse current and temperature data of the switching power supply also change accordingly.

[0031] S102, smoothing the historical pulse current within a predetermined historical time period to obtain a smoothed rectangular pulse current.

[0032] Specifically, for a switching power supply, the main heat generated during operation is due to high-frequency operation. Under high-frequency operation, the pulse current often appears as a rectangular square wave. Therefore, the embodiment of the present invention first smoothes the historical pulse current within a predetermined time period to obtain a rectangular pulse current.

[0033] Furthermore, when smoothing the historical pulse current, as an optional embodiment of the present invention, firstly, at least one time period is randomly selected from a predetermined historical time period; then, based on the average value of the historical pulse current in the time period and the historical pulse current at each acquisition point in the time period, the probability that the historical pulse current in the time period belongs to a rectangular pulse peak is determined; secondly, a first target time period in which the probability of a rectangular pulse peak is greater than a first threshold is selected, and the average value of all historical pulse currents in the first target time period is taken as the current value of the first target time period, and the current value of the time period in which the probability of a rectangular pulse peak is not greater than the first threshold is taken as a predetermined value, to obtain a smoothed rectangular pulse current.

[0034] Specifically, since the standard form of the pulse current is a rectangular square wave, all rectangular square waves are first determined and smoothed. The current difference in the wave top period is small, and the overall current is large on this basis. Therefore, the historical pulse current can be smoothed by the probability that the historical pulse current in any time period belongs to the rectangular pulse peak. Among them, at least one time period in the predetermined historical time period can be selected from multiple time periods in the predetermined historical time period. As an optional embodiment of the present invention, the following formula can be used to calculate the probability that the historical pulse current in the time period belongs to the rectangular pulse peak:

[0035]

[0036] In the above formula, Indicates any selected value within a predetermined historical period. The probability that the historical pulse currents within the time period all belong to rectangular pulse peaks. Represents the maximum and minimum normalization function, which is Perform normalization. Indicates any selected value within a predetermined historical period. The average value of the historical pulse current in the time period. n represents The number of historical pulse currents in the time period, express The i-th historical pulse current in the time period.

[0037] Furthermore, after determining the probability that the historical pulse current in each time period belongs to the rectangular pulse peak, all time periods in which the probability that the historical pulse current in the time period belongs to the rectangular pulse peak is greater than the first threshold are selected. Since any time period in the rectangular wave top segment meets the above probability, and these time periods must be included in the rectangular wave top time period, the union of all first target time periods is obtained, and the average value of the historical pulse currents in all time periods in the union is taken as the current value of the first target time period. The current values ​​of the remaining time periods that are not in the union are taken as predetermined values, and the smoothed rectangular pulse current can be obtained. Among them, the first threshold value and the predetermined value can be determined according to actual conditions. In the embodiment of the present invention, the first threshold value is taken as 0.9, and the predetermined value is taken as 0. Figure 4 As shown, Figure 4 A schematic diagram of a smoothed rectangular pulse current provided by an embodiment of the present invention, Figure 4 It includes a rectangular wave top and a rectangular wave bottom. The current value of the rectangular wave top is the average value of the historical pulse current in each time period, and the current value of the rectangular wave bottom is 0.

[0038] S103, using the historical temperature data at different historical moments within a predetermined historical time period and the rectangular pulse current to determine the first desirability of the historical temperature data at each historical moment.

[0039] Specifically, during the operation of the switching power supply, the main heat is generated by high-frequency operation, so there is a positive relationship between the frequency and temperature change of the switching power supply, which can be reflected by the frequency-temperature proportionality coefficient. Therefore, if the historical temperature data of the switching power supply at a certain moment is true, the more similar the frequency-temperature proportionality coefficient is to the surrounding historical temperature data, the higher the desirability of the historical temperature data at that moment.

[0040] Further, when determining the first desirability of the historical temperature data of each historical moment, as an optional embodiment of the present invention, first determine the first temperature data of the first historical moment and the second temperature data of at least one target historical moment around the first historical moment; then determine the second target time period in which the first historical moment and the target historical moment are located, and the first number of intersections of the rectangular pulse current and the predetermined current value in the second target time period; secondly determine the frequency-temperature proportional coefficient between the first temperature data and the second temperature data based on the first temperature data, the second temperature data and the first number; finally, determine the first desirability of the first temperature data based on the frequency-temperature proportional coefficient of each target historical moment.

[0041] Specifically, at least one target historical moment around the first historical moment refers to at least one target historical moment that is closest to the first historical moment. If there are 4 target historical moments, the two historical moments before the first historical moment and the two historical moments after the first historical moment are taken as the target historical moments. The second target time period in which the first historical moment and the target historical moment are located refers to the time period composed of the first historical moment and the target historical moment. The first number of intersections of the rectangular pulse current and the predetermined current value in the second target time period can be regarded as the frequency of the switching power supply. In the embodiment of the present invention, the predetermined current value is taken as 10, and the rectangular pulse current in the second target time period is marked with I=10. The number of intersections of the rectangular pulse current and I=10 in the second target time period is the first number.

[0042] Further, when determining the frequency-temperature proportional coefficient between the first temperature data and the second temperature data, as an optional embodiment of the present invention, the absolute value of the first difference between the first temperature data and the second temperature data is calculated; and the first ratio of the first quantity to the first difference is determined as the frequency-temperature proportional coefficient.

[0043] Specifically, the frequency-temperature proportionality coefficient can be calculated using the following formula:

[0044]

[0045] In the above formula, Represents the first temperature data of the first historical moment Q and the i-th target historical moment around it The frequency-temperature proportionality coefficient between the second temperature data. Represents the first temperature data at the first historical moment Q and its i-th target historical moment The first number of intersections between the smoothed rectangular pulse current and I=10 within the second target time period where the second temperature data is located. Represents the first temperature data at the first historical moment Q. Represents the i-th target historical moment The second temperature data.

[0046] Further, when determining the first desirability of the first temperature data, as an optional embodiment of the present invention, the average value of the frequency-temperature proportional coefficient between the first temperature data and the second temperature data at each target historical moment is determined; the second difference between the frequency-temperature proportional coefficient between the first temperature data and the second temperature data at each target historical moment and the average value is calculated respectively, and the second difference values ​​are superimposed to obtain a first superimposed value; the first superimposed value is inversely normalized to obtain the first desirability.

[0047] Specifically, the embodiment of the present invention uses the following formula to calculate the first desirability:

[0048]

[0049] In the above formula, represents the first desirability of the first temperature data at the first historical moment Q. exp represents an exponential function with e as the base, which is used to Perform inverse proportional normalization. s represents the number of target historical moments around the first historical moment Q. Represents the first temperature data of the first historical moment Q and the i-th target historical moment around it The frequency-temperature proportionality coefficient between the second temperature data. Represents the first temperature data of the first historical moment Q and the i-th target historical moment around it The average value of the frequency-temperature proportionality coefficient between the second temperature data.

[0050] S104, determining an initial temperature threshold of the switching power supply at the initial moment by using the initial temperature data of the switching power supply at the initial moment.

[0051] Specifically, the initial moment refers to the moment when the switching power supply is started. For the initial moment, the switching power supply has no change in working state, so the embodiment of the present invention needs to customize the initial temperature threshold. The embodiment of the present invention determines the first sum between the initial temperature data and the allowed floating value as the initial temperature threshold, and the allowed floating value is the first product of the initial temperature data and the preset percentage.

[0052] The preset percentage can be determined according to actual conditions, and in the embodiment of the present invention, the value is 10%. Further, the initial temperature threshold can be calculated using the following formula:

[0053]

[0054] In the above formula, Indicates the initial temperature threshold at the initial moment. Indicates the initial temperature data at the initial time.

[0055] S105, determining a temperature protection threshold at the next moment of the initial moment by using the first desirability of the historical temperature data at different historical moments, the rectangular pulse current at different historical moments, the initial temperature threshold and the initial temperature data.

[0056] Specifically, for the initial moment of the switching power supply, the initial temperature threshold has been determined. Next, the temperature protection threshold of the next moment of the initial moment needs to be determined. In the embodiment of the present invention, the target historical temperature data that is the same as the initial temperature data is first found from a predetermined historical time period, and the corresponding target historical moment is determined. The temperature change values ​​of the target historical moment and the next historical moment are determined respectively. The contribution rates of these change values ​​to the temperature protection threshold of the next moment are different. Therefore, data of the type of working condition of the switching power supply at the current moment are selected from the historical temperature data. In the embodiment of the present invention, the second desirability is used to represent the desirability of the temperature difference in the historical temperature data relative to the temperature difference from the initial moment to the next moment. The higher the second desirability, the closer the selected historical temperature data is to the working state of the switching power supply from the initial moment to the next moment. Finally, the correction value of the initial temperature threshold is determined by the temperature change values ​​in these historical temperature data.

[0057] Further, when determining the temperature protection threshold of the next moment of the initial moment, as an optional embodiment of the present invention, first, the target historical temperature data identical to the initial temperature data is selected from a predetermined historical time period to determine the target historical moment where the target historical temperature data identical to the initial temperature data is located; then, the second desirability is determined based on the first desirability of the target historical temperature data, the rectangular pulse current in the first time period from the target historical moment to the next historical moment, and the rectangular pulse current in the second time period from the initial moment to the next moment, the second desirability being the desirability of the temperature difference between the target historical temperature data of the target historical moment and the historical temperature data of the next historical moment with respect to the initial temperature data of the initial moment to the temperature data of the next moment; finally, the temperature protection threshold of the next moment of the initial moment is determined using the second desirability, the initial temperature threshold, the target historical temperature data of the target historical moment, and the historical temperature data of the next historical moment of the target historical moment.

[0058] Specifically, in the embodiment of the present invention, the current moment is determined The initial temperature data of the same target historical moment Target historical temperature data. In the embodiment of the present invention, the target historical time The number of target historical temperature data is recorded as v. It is worth noting that at the current moment That is, it may be the initial moment in the embodiment of the present invention.

[0059] Further, when determining the second desirability, as an optional embodiment of the present invention, first determine the second number of intersections of the rectangular pulse current and the predetermined current value in the first time period between the target historical moment and the next historical moment of the target historical moment, and the third number of intersections of the rectangular pulse current and the predetermined current value in the second time period from the initial moment to the next moment; then calculate the second sum between the first desirability of the target historical temperature data at the target historical moment and the first desirability of the historical temperature data at the next historical moment of the target historical moment; secondly calculate the reciprocal of the absolute value of the third difference between the second number and the third number, and use the maximum and minimum normalization function to process the reciprocal of the absolute value of the third difference to obtain a normalized value; finally determine the second product of the second sum and the normalized value as the second desirability.

[0060] Specifically, the predetermined current value can be determined according to actual conditions, and in the embodiment of the present invention, the value is 10. Furthermore, in the embodiment of the present invention, the second desirability is calculated using the following formula:

[0061]

[0062] In the above formula, Indicates the target historical moment The target historical temperature data and its next historical moment The temperature difference between the historical temperature data for the current moment The initial temperature data to the next moment The second desirability is the temperature difference between the temperature data. Indicates the target historical moment The first desirability of the target historical temperature data, Indicates the target historical moment The next historical moment The first desirability of historical temperature data. Represents the maximum and minimum normalization function, which is used to Perform normalization. Indicates the current time Until the next moment The third number of intersections of the smoothed rectangular pulse current and I=10 in the second time period. Indicates the target historical moment Its next historical moment The second number of intersections of the smoothed rectangular pulse current and I=10 in the first time period.

[0063] Furthermore, when determining the temperature protection threshold value at the next moment after the initial moment, as an optional embodiment of the present invention, firstly, a second superposition value of the second desirability of the target historical temperature data at each target historical moment is calculated; then, a second ratio of the second desirability of each target historical moment to the second superposition value, and a fourth difference between the target historical temperature data at each target historical moment and the historical temperature data at the next historical moment after the target historical moment are calculated; then, a third product between each second ratio and each fourth difference is calculated, and each third product is superimposed to obtain a third superposition value; finally, a third sum between the third superposition value and the initial temperature threshold is determined as the temperature protection threshold value at the next moment after the initial moment.

[0064] Specifically, the temperature protection threshold is calculated using the following formula in the embodiment of the present invention:

[0065]

[0066] In the above formula, Indicates the current time The next moment The temperature protection threshold. Indicates the current time The initial temperature threshold. Indicates the target historical moment The target historical temperature data and its next historical moment The temperature difference between the historical temperature data for the current moment The initial temperature data to the next moment The second desirability is the temperature difference between the temperature data. v represents the temperature difference between the current time The number of target historical temperature data that are the same as the initial temperature data, Representing historical moments Historical temperature data. Indicates the target historical moment Target historical temperature data.

[0067] S106, performing over-temperature fault diagnosis on the switching power supply according to the temperature protection threshold at the next moment.

[0068] Specifically, when performing over-temperature fault diagnosis, the real-time temperature of the switching power supply is first monitored in real time, and the real-time temperature is compared with the temperature protection threshold. If the temperature exceeds the temperature protection threshold, the over-temperature protection mechanism is activated to determine that the switching power supply has an over-temperature fault. The over-temperature protection mechanism includes at least one of reducing power output, starting a cooling system, and directly shutting down the power supply.

[0069] In the embodiment of the present invention, a dynamic temperature protection threshold is set for the over-temperature protection mechanism through the historical temperature data and historical pulse current of the switching power supply, and the dynamic temperature protection threshold is obtained by updating the initial temperature threshold of the previous moment. When the over-temperature fault diagnosis of the switching power supply is performed at the current moment, the temperature of the switching power supply at the current moment is monitored in real time, and it is compared with the updated temperature protection threshold, so as to achieve the purpose of over-temperature fault diagnosis. Therefore, the embodiment of the present invention performs over-temperature fault diagnosis on the switching power supply by setting a dynamic temperature protection threshold, thereby reducing the number of unnecessary false alarms and improving the reliability and accuracy of the over-temperature protection mechanism of the switching power supply.

[0070] Embodiment 2:

[0071] Corresponding to the switching power supply fault diagnosis method provided in the above embodiment, based on the same technical concept, an embodiment of the present invention further provides a switching power supply fault diagnosis system, which is used to execute the above switching power supply fault diagnosis method. Figure 5 A schematic diagram of a switching power supply fault diagnosis system provided by an embodiment of the present invention is shown in FIG. Figure 5 The switching power supply fault diagnosis system may have relatively large differences due to different configurations or performances, and may include one or more processors 501 and memory 502, the memory 502 is used to store computer programs that can be run on the processor 501, and the processor 501 is used to execute the program stored in the memory 502 to achieve the above Figure 1 The various steps in the method embodiment. The memory 502 may be a temporary storage or a permanent storage. The application stored in the memory 502 may include one or more modules (not shown in the figure), and each module may include a series of computer executable instructions in the switching power supply fault diagnosis system.

[0072] Furthermore, the processor 501 can be configured to communicate with the memory 502, and execute a series of computer executable instructions in the memory 502 on the switching power supply fault diagnosis system. The switching power supply fault diagnosis system can also include one or more power supplies 503, one or more wired or wireless network interfaces 504, one or more input and output interfaces 505, and one or more keyboards 506.

[0073] Specifically in this embodiment, the switching power supply fault diagnosis system includes a processor, a communication interface, a memory and a communication bus; wherein the processor, the communication interface and the memory communicate with each other through the bus; the memory is used to store computer programs; the processor is used to execute the programs stored in the memory to achieve the above Figure 1The various steps in the method embodiment are similar to those in the method embodiment, and have the beneficial effects of the above method embodiments. To avoid repetition, the embodiments of the present invention will not be described in detail here.

[0074] It should be noted that the switching power supply fault diagnosis system provided in the embodiment of the present invention and the switching power supply fault diagnosis method provided in the embodiment of the present invention are based on the same application concept, so the specific implementation of this embodiment can refer to the implementation of the aforementioned switching power supply fault diagnosis method, and has the same or similar beneficial effects, and the repeated parts will not be repeated.

[0075] It should be noted that the sequence of the above embodiments of the present invention is only for description and does not represent the advantages and disadvantages of the embodiments. The processes depicted in the accompanying drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0076] The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referenced to each other, and each embodiment focuses on the differences from other embodiments.

Claims

1. A switching power supply fault diagnosis method, characterized in that: The switching power supply fault diagnosis method comprises: Obtain historical pulse current and historical temperature data of the switching power supply within a predetermined historical time period; Smoothing the historical pulse current within the predetermined historical time period to obtain a smoothed rectangular pulse current; Determine the first desirability of the historical temperature data at each of the historical moments by using the historical temperature data at different historical moments within the predetermined historical time period and the rectangular pulse current; Determining an initial temperature threshold of the switching power supply at the initial moment by using the initial temperature data of the switching power supply at the initial moment; Determine a temperature protection threshold at a next moment of the initial moment by using the first desirability of the historical temperature data at different historical moments, the rectangular pulse current at different historical moments, the initial temperature threshold and the initial temperature data; Performing over-temperature fault diagnosis on the switching power supply according to the temperature protection threshold at the next moment; Wherein, the method for obtaining the first desirability is: determining the first temperature data of the first historical moment and the second temperature data of at least one target historical moment around the first historical moment; determining the second target time period in which the first historical moment and the target historical moment are located, and the first number of intersections of the rectangular pulse current and the predetermined current value in the second target time period; determining the frequency-temperature proportional coefficient between the first temperature data and the second temperature data according to the first temperature data, the second temperature data and the first number; determining the first desirability of the first temperature data according to the frequency-temperature proportional coefficient of each target historical moment; Among them, the method for obtaining the temperature protection threshold is: select the target historical temperature data that is the same as the initial temperature data from the predetermined historical time period, and determine the target historical moment where the target historical temperature data that is the same as the initial temperature data is located; determine the second desirability based on the first desirability of the target historical temperature data, the rectangular pulse current in the first time period from the target historical moment to the next historical moment, and the rectangular pulse current in the second time period from the initial moment to the next moment, the second desirability being the desirability of the temperature difference between the target historical temperature data at the target historical moment and the historical temperature data at the next historical moment for the initial temperature data at the initial moment to the temperature data at the next moment; use the second desirability, the initial temperature threshold, the target historical temperature data at the target historical moment, and the historical temperature data at the next historical moment of the target historical moment to determine the temperature protection threshold at the next moment of the initial moment.

2. The switching power supply fault diagnosis method according to claim 1, characterized in that: The smoothing of the historical pulse current within the predetermined historical time period to obtain the smoothed rectangular pulse current includes: Randomly select at least one time period from the predetermined historical time period; Determine the probability that the historical pulse current in the time period belongs to a rectangular pulse peak according to the average value of the historical pulse current in the time period and the historical pulse current at each acquisition point in the time period; A first target time period in which the probability of the rectangular pulse peak is greater than a first threshold is selected, the average value of all historical pulse currents in the first target time period is taken as the current value of the first target time period, and the current value of the time period in which the probability of the rectangular pulse peak is not greater than the first threshold is taken as a predetermined value to obtain a smoothed rectangular pulse current.

3. The switching power supply fault diagnosis method according to claim 1, characterized in that: The determining of the frequency-temperature proportionality coefficient between the first temperature data and the second temperature data according to the first temperature data, the second temperature data and the first quantity comprises: calculating an absolute value of a first difference between the first temperature data and the second temperature data; A first ratio of the first number to the first difference is determined as the frequency-temperature proportionality coefficient.

4. The switching power supply fault diagnosis method according to claim 1, characterized in that: The first desirability of determining the first temperature data according to the frequency-temperature proportionality coefficient of each target historical moment includes: Determine an average value of a frequency-temperature proportionality coefficient between the first temperature data and the second temperature data at each of the target historical moments; respectively calculating second differences between the frequency-temperature proportional coefficient and the average value between the first temperature data and the second temperature data at each of the target historical moments, and superimposing each of the second differences to obtain a first superimposed value; The first superposition value is subjected to inverse proportional normalization processing to obtain the first desirability.

5. The switching power supply fault diagnosis method according to claim 1, characterized in that: The determining the initial temperature threshold of the switching power supply at the initial moment by using the initial temperature data of the switching power supply at the initial moment comprises: A first sum value between the initial temperature data and an allowable floating value is determined as the initial temperature threshold, and the allowable floating value is a first product of the initial temperature data and a preset percentage.

6. The switching power supply fault diagnosis method according to claim 1, characterized in that: Determining the second desirability according to the first desirability of the target historical temperature data, the rectangular pulse current in a first time period from the target historical moment to the next historical moment, and the rectangular pulse current in a second time period from the initial moment to the next moment includes: Determine a second number of intersections between the rectangular pulse current and the predetermined current value in a first time period between the target historical moment and the next historical moment of the target historical moment, and a third number of intersections between the rectangular pulse current and the predetermined current value in a second time period from the initial moment to the next moment; Calculating a second sum value between a first desirability of the target historical temperature data at the target historical moment and a first desirability of the historical temperature data at a next historical moment of the target historical moment; Calculating the reciprocal of the absolute value of a third difference between the second quantity and the third quantity, and processing the reciprocal of the absolute value of the third difference using a maximum and minimum value normalization function to obtain a normalized value; A second product of the second sum value and the normalized value is determined as the second desirability.

7. The switching power supply fault diagnosis method according to claim 1, characterized in that: The step of determining the temperature protection threshold at the next moment of the initial moment by using the second desirability, the initial temperature threshold, the target historical temperature data at the target historical moment, and the historical temperature data at the next historical moment of the target historical moment comprises: Calculate a second superposition value of a second desirability of the target historical temperature data at each of the target historical moments; Calculating a second ratio of the second desirability of each target historical moment to the second superposition value, and a fourth difference between the target historical temperature data of each target historical moment and the historical temperature data of a next historical moment of the target historical moment; Calculating a third product between each of the second ratios and each of the fourth differences, and superimposing each of the third products to obtain a third superimposed value; A third sum value between the third superposition value and the initial temperature threshold is determined as a temperature protection threshold at a moment next to the initial moment.

8. A switching power supply fault diagnosis system, characterized in that: The switching power supply fault diagnosis system comprises: a processor and a memory; wherein the memory is used to store a computer program that can be run on the processor; and the processor is used to execute the program stored in the memory to implement the steps of the switching power supply fault diagnosis method as described in any one of claims 1 to 7.

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