A method, device, storage medium and electronic device for determining switching power supply circuit loss

Abstract

The embodiment of the present application discloses a method, device, storage medium and electronic device for determining the loss of a switching power supply circuit, wherein the method includes: monitoring the voltage wave parameters input by an AC input source and rectified by a rectifier bridge, determining a voltage wave model for the electrolytic capacitor based on the voltage wave parameters, and the electrolytic capacitor is connected to both ends of the rectifier bridge; constructing an initial input current function for the switching power supply circuit based on the electrical parameter characteristics corresponding to the voltage wave model, determining the electrical parameter average value and electrolytic output power equation for the electrolytic capacitor based on the voltage wave model and the initial input current function; determining the circuit current parameters for the switching power supply circuit based on the initial input current function, the electrical parameter average value and the electrolytic output power equation; determining the device loss parameters for the switching power supply circuit based on the circuit current parameters. By using the embodiment of the present application, the circuit loss can be determined to realize the loss quantification of complex circuits.

Description

Technical Field

[0001] The present application relates to the field of computer technology, and in particular to a method, device, storage medium and electronic device for determining the loss of a switching power supply circuit. Background Art

[0002] With the rapid development of electronic technology, application scenarios involving switching power supply circuits are becoming more and more common. Switching power supply circuits are widely used in industries, Internet of Things, display devices, etc. due to their advantages of high efficiency, high reliability, and small size. When the switching power supply circuit is working, at least one power device (such as a thermistor, etc.) involved in the switching power supply circuit will generate device power loss due to factors such as device heating. Summary of the invention

[0003] The embodiments of the present application provide a method, device, storage medium and electronic device for determining the loss of a switching power supply circuit. The technical solution is as follows:

[0004] In a first aspect, an embodiment of the present application provides a method for determining a switching power supply circuit loss, the method comprising:

[0005] Monitoring voltage wave parameters inputted by an AC input source and rectified by a rectifier bridge, and determining a voltage wave model for the electrolytic capacitor based on the voltage wave parameters, wherein the electrolytic capacitor is connected to both ends of the rectifier bridge;

[0006] Constructing an initial input current function for the switching power supply circuit based on the electrical parameter characteristics corresponding to the voltage wave model, and determining an electrical parameter average value and an electrolytic output power equation for the electrolytic capacitor based on the voltage wave model and the initial input current function;

[0007] Determining circuit current parameters for a switching power supply circuit based on an initial input current function, the electrical parameter average value, and the electrolysis output power equation;

[0008] A device loss parameter for the switching power supply circuit is determined based on the circuit current parameter.

[0009] In a second aspect, an embodiment of the present application provides a switching power supply circuit loss determination device, the device comprising:

[0010] a voltage wave model determination module, used to monitor the voltage wave parameters input by the AC input source and rectified by the rectifier bridge, and determine the voltage wave model for the electrolytic capacitor based on the voltage wave parameters, wherein the electrolytic capacitor is connected to both ends of the rectifier bridge;

[0011] An electrical parameter power determination module, used to construct an initial input current function for the switching power supply circuit based on the electrical parameter characteristics corresponding to the voltage wave model, and determine an electrical parameter average value and an electrolytic output power equation for the electrolytic capacitor based on the voltage wave model and the initial input current function;

[0012] A current parameter determination module, configured to determine a circuit current parameter for the switching power supply circuit based on the initial input current function, the average value of the electric parameter and the electrolysis output power equation;

[0013] A device loss determination module is used to determine the device loss parameters for the switching power supply circuit based on the circuit current parameters. In a third aspect, an embodiment of the present application provides a computer storage medium, wherein the computer storage medium stores a plurality of instructions, wherein the instructions are suitable for being loaded by a processor and executing the above method steps.

[0014] In a fourth aspect, an embodiment of the present application provides an electronic device, which may include: a processor and a memory; wherein the memory stores a computer program, and the computer program is suitable for being loaded by the processor and executing the above-mentioned method steps.

[0015] The beneficial effects brought about by the technical solutions provided by some embodiments of the present application include at least:

[0016] In one or more embodiments of the present application, the electronic device monitors the voltage wave parameters input by the AC input source and rectified by the rectifier bridge, and determines the voltage wave model for the electrolytic capacitor based on the voltage wave parameters, and the electrolytic capacitor is connected to the two ends of the rectifier bridge; then, based on the electrical parameter characteristics corresponding to the voltage wave model, an initial input current function for the switching power supply circuit is constructed, and then based on the voltage wave model and the initial input current function, the electrical parameter average value and the electrolytic output power equation for the electrolytic capacitor are determined; then, based on the initial input current function, the electrical parameter average value and the electrolytic output power equation, the circuit current parameters for the switching power supply circuit are determined; finally, based on the circuit current parameters, the device loss parameters for the switching power supply circuit are determined. By first quantifying the working electrical parameters of the electrolytic capacitor device at the back end of the circuit to determine the input current in the circuit, and then determining the loss of the power device in the circuit, the loss calculation of the corresponding scenario of complex circuit state such as switching power supply circuit is realized, the loss uncertainty existing in the switching power supply circuit in the actual application environment is overcome, the loss quantification and current quantification of the complex circuit are realized, and the accuracy of loss monitoring is ensured; and, in some embodiments, for the case of irregular input current, a trigonometric sine equivalent method is used for calculation, which simplifies the calculation difficulty, and the error is small through actual comparison verification, thereby improving the accuracy of loss quantification; and, in some embodiments, for devices such as semiconductor rectifier bridges, a temperature coefficient is creatively introduced into the switching power supply circuit to reflect the state of the device at various working temperatures, thereby realizing the loss calculation of the device at different working temperatures. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0018] Figure 1 It is a flow chart of a method for determining a switching power supply circuit loss provided in an embodiment of the present application;

[0019] Figure 2 is a circuit diagram of a switching power supply circuit involved in an embodiment of the present application;

[0020] Figure 3 It is a flow chart of another method for determining the circuit loss of a switching power supply provided in an embodiment of the present application;

[0021] Figure 4 is a schematic diagram of a voltage waveform in the implementation of this application;

[0022] Figure 5 is a schematic diagram of another voltage waveform in the implementation of the present application;

[0023] Figure 6 A schematic diagram of an input current waveform involved in the present application;

[0024] Figure 7 A waveform diagram corresponding to a relevant electrical parameter involved in this application;

[0025] Figure 8 It is a flow chart of another method for determining the circuit loss of a switching power supply provided in an embodiment of the present application;

[0026] Fig. 9 It is a schematic diagram of a temperature resistance change curve involved in the present application;

[0027] Fig.10 is a schematic diagram of a VF / IF fitting curve of a diode involved in the present application;

[0028] Fig.11 It is a schematic diagram of temperature and on-state voltage involved in the present application;

[0029] Fig.12 It is a table schematic diagram related to the conduction voltage involved in this application;

[0030] Fig.13 It is a schematic diagram of the temperature coefficient curve of the rectifier bridge in this application;

[0031] Fig.14 It is a structural schematic diagram of a switching power supply circuit loss determination device provided in an embodiment of the present application;

[0032] Fig.15 It is a structural schematic diagram of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0034] In the description of the present application, it should be understood that the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In the description of the present application, it should be noted that, unless otherwise clearly specified and limited, "including" and "having" and any of their variations are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally also includes steps or units that are not listed, or optionally also includes other steps or units inherent to these processes, methods, products or devices. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood in specific circumstances. In addition, in the description of the present application, unless otherwise specified, "multiple" refers to two or more. "And / or" describes the association relationship of associated objects, indicating that there can be three relationships, for example, A and / or B, which can represent: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the associated objects before and after are an "or" relationship.

[0035] The present application is described in detail below with reference to specific embodiments.

[0036] In one embodiment, Figure 1 As shown, a method for determining the circuit loss of a switching power supply is proposed, which can be implemented by a computer program and can be run on a switching power supply circuit loss determination device based on the von Neumann system. The computer program can be integrated in an application or run as an independent tool application. The switching power supply circuit loss determination device can be a terminal device, including but not limited to: a personal computer, a tablet computer, a handheld device, a vehicle-mounted device, a wearable device, a computing device or other processing device connected to a wireless modem. In different networks, terminal devices can be called different names, such as: user equipment, access terminal, user unit, user station, mobile station, mobile station, remote station, remote terminal, mobile device, user terminal, terminal, wireless communication device, user agent or user device, cellular phone, cordless phone, 5G network or terminal equipment in future evolution network, etc.

[0037] Specifically, the method for determining the switching power supply circuit loss includes:

[0038] S101: monitoring voltage wave parameters inputted by an AC input source and rectified by the rectifier bridge, and determining a voltage wave model for the electrolytic capacitor based on the voltage wave parameters, wherein the electrolytic capacitor is connected to both ends of the rectifier bridge.

[0039] In practical applications, application scenarios involving switching power supply circuits are becoming more and more common. Switching power supply circuits are widely used in industries, Internet of Things, display devices, etc. due to their advantages of high efficiency, high reliability, and small size. The switching power supply circuit involved in this application may be a switching power supply circuit that does not include a PFC (power factor correction) part (such as devices, modules, circuits, etc.). The switching power supply circuit in this application is often used in electronic devices corresponding to power supply boards in a specified power range (such as below 75w);

[0040] A common switching power supply circuit may include at least an AC input source, a thermistor, a capacitor, a common-mode inductor, a rectifier bridge, and an electrolytic capacitor and other electronic components, such as Figure 2 As shown, Figure 2 is a circuit diagram of a switching power supply circuit involved in an embodiment of the present application, Figure 2 In the embodiment, the switching power supply circuit includes an AC input source AC, a thermistor NTCB1, a capacitor CXB1, a common mode inductor LCB1, a rectifier bridge DB1 and an electrolytic capacitor EB1.

[0041] exist Figure 2 In the embodiment, the AC input source AC is connected to the thermistor NTCB1 and one end of the capacitor CXB1 respectively, the thermistor NTCB1 is connected to the other end of the capacitor CXB1, the two ends of the capacitor CXB1 are connected to the two electrical interfaces on one side of the common-mode inductor LCB1 respectively, the two electrical interfaces on the other side of the common-mode inductor LCB1 are connected to the rectifier bridge DB1, and the two electrical interfaces of the rectifier bridge DB1 are connected to the two ends of the electrolytic capacitor EB1 respectively.

[0042] In the present application, the AC input source is used as the power input, and is input and passed through the thermistor NTCB1, the capacitor CXB1, the common mode inductor LCB1, and then rectified by the rectifier bridge DB1 to provide the input voltage for the electrolytic capacitor EB1. During the operation of the aforementioned circuit, the voltage wave parameters input by the AC input source and rectified by the rectifier bridge can be detected by the main electronic device. Figure 2 Take for example the voltage wave parameters at both ends of the electrolytic capacitor EB1.

[0043] Specifically, the electronic device can monitor the voltage wave parameters input by the AC input source and rectified by the rectifier bridge. Usually, there is a certain periodic fluctuation law in the voltage wave parameters within a period of time. In this application, the periodic fluctuation law within a period of time is usually detected to construct a voltage wave model for the electrolytic capacitor. In actual implementation, the instantaneous change parameters of the voltage at both ends of the electrolytic capacitor during the monitoring period can be collected, and all the instantaneous change parameters of the voltage during the monitoring period can be mathematically processed. A mathematical processing method can draw a curve of the instantaneous change of the voltage at both ends of the electrolytic capacitor within a certain monitoring period, and the curve is model-fitted based on the instantaneous change curve of the voltage, so as to construct a voltage wave model for the electrolytic capacitor. Furthermore, the voltage wave model is a numerical change model for time t and voltage wave parameter V, that is, based on the voltage wave model, the actual voltage wave parameter V can be determined based on any time point.

[0044] In practical applications, since the switching power supply circuit contains electrolytic capacitors, due to the device characteristics of the electrolytic capacitors, at least the charging stage and the discharging stage of the electrolytic capacitors are included. In the charging stage, the electrolytic capacitors do not output electrical signals to the circuit, and in the discharging stage, the electrolytic capacitors will output electrical signals to the circuit.

[0045] S102: constructing an initial input current function for the switching power supply circuit based on the electrical parameter characteristics corresponding to the voltage wave model, and determining the electrical parameter average value and electrolytic output power equation for the electrolytic capacitor based on the voltage wave model and the initial input current function.

[0046] The electrical parameter characteristics are mainly due to the inclusion of electrolytic capacitors in the switching power supply circuit. The device characteristic voltage wave model based on the electrolytic capacitor will correspond to different model internal structures in the corresponding stages. In layman's terms, when the electrolytic capacitor works in the switching power supply circuit, since it at least includes the charging stage and the discharging stage of the electrolytic capacitor, the model internal structure of the power wave model in the charging stage and the discharging stage is usually different. Therefore, the electrical parameter characteristics may at least include the time characteristics corresponding to the charging stage and the discharging stage, the model internal structure characteristics corresponding to the charging stage and the discharging stage (which can be understood as different model internal expressions, such as the charging stage corresponds to the model internal expression A, and the discharging stage corresponds to the model internal expression B), the voltage waveform period characteristics, the amplitude characteristics, and the like.

[0047] In the present application, a mathematical analysis prediction is performed based on a determined voltage wave model and the current change is quantified. In some embodiments, the voltage value fluctuation curve corresponding to the aforementioned determined voltage wave model is similar to the curve fluctuation of a sine function. By mathematically quantifying the voltage waveform, since the voltage fluctuation characteristics are usually highly correlated with the current fluctuations, the current fluctuations can be further quantified based on the voltage fluctuation characteristics (that is, the electrical parameter characteristics), and then the initial input current function (also referred to as the current model) for the switching power supply circuit can be constructed. In the present application, for the switching power supply circuit, the aforementioned determined voltage wave model and the initial input current function feedback the fluctuation quantification of the voltage dimension and the current dimension of the device in the switching power supply circuit. After determining the voltage wave model and the initial input current function, the present application can further calculate the average value of the electrical parameters. The average value of the electrical parameters can be the average voltage value and the average current value for the electrolytic capacitor. Due to the device composition characteristics of the switching power supply circuit, the power consumption of the working device in the entire switching power supply circuit can be quantified based on the average current value.

[0048] Furthermore, after the average voltage value and the average current value are determined, the electrolytic output power equation for the electrolytic capacitor can be determined.

[0049] S103: Determine circuit current parameters for the switching power supply circuit based on the initial input current function, the average value of the electrical parameters, and the electrolysis output power equation.

[0050] In an embodiment of the present application, since the initial input current function is constructed by only mathematically quantifying the current change in the switching power supply circuit, the parameters in the initial current function (that is, the unknown parameters in the initial current function, such as the maximum current in some embodiments) can be determined in combination with the initial input current function, the average value of the electrical parameters, and the electrolysis output power equation during the entire process, so that the circuit current parameters for the switching power supply circuit can be ultimately determined. For example, based on the initial input current function, the average value of the electrical parameters, and the electrolysis output power equation, the maximum value of the input current can be further determined, so that the effective value of the current involved in the circuit loss calculation can be further determined.

[0051] S104: Determine device loss parameters for the switching power supply circuit based on the circuit current parameters.

[0052] In some embodiments, the circuit current parameter can be the effective value of the current for the entire switching power supply circuit, and then can be combined with the device characteristics of each power consumption device in the switching power supply circuit. The device loss parameters of each power consumption device in the switching power supply circuit can be determined respectively by combining the device characteristics and the effective value of the current, that is, the device power consumption loss of each power consumption device. In some embodiments, the aforementioned power consumption devices are often thermistors, common-mode inductors and rectifier bridges in the switching power supply circuit.

[0053] It should be noted that in this embodiment, steps S101-S104 only provide an adaptive description of the method for determining the switching power supply circuit loss in this application, and other technical details not involved may refer to other embodiments in this application.

[0054] In an embodiment of the present application, the electronic device monitors the voltage wave parameters input by the AC input source and rectified by the rectifier bridge, and determines the voltage wave model for the electrolytic capacitor based on the voltage wave parameters, and the electrolytic capacitor is connected to the two ends of the rectifier bridge; then, based on the electrical parameter characteristics corresponding to the voltage wave model, an initial input current function for the switching power supply circuit is constructed, and then based on the voltage wave model and the initial input current function, the electrical parameter average value and the electrolytic output power equation for the electrolytic capacitor are determined; then, based on the initial input current function, the electrical parameter average value and the electrolytic output power equation, the circuit current parameters for the switching power supply circuit are determined; finally, based on the circuit current parameters, the device loss parameters for the switching power supply circuit are determined. By first quantifying the working electrical parameters of the electrolytic capacitor device at the back end of the circuit to determine the input current in the circuit, and then determining the loss of the power device in the circuit, the loss calculation of the corresponding scenario of the complex circuit state such as the switching power supply circuit is realized, and the loss uncertainty existing in the switching power supply circuit in the actual application environment is overcome, and the loss quantification and current quantification of the complex circuit are realized, ensuring the accuracy of loss monitoring; and, in some embodiments, for the case of irregular input current, a trigonometric sine equivalent method is used for calculation, which simplifies the calculation difficulty, and the error is small through actual comparison verification, thereby improving the accuracy of loss quantification; and, in some embodiments, for devices such as semiconductor rectifier bridges, a temperature coefficient is creatively introduced into the switching power supply circuit to reflect the state of the device at various working temperatures, thereby realizing the loss calculation of the device at different working temperatures.

[0055] See also Figure 3 , Figure 3 This is a flow chart of another embodiment of a method for determining the loss of a switching power supply circuit proposed in this application. Specifically:

[0056] S201: monitoring the voltage wave parameters inputted by the AC input source and rectified by the rectifier bridge.

[0057] Please refer to step S101 for details, which will not be described again here.

[0058] S202: Determine voltage waveform periodic characteristics for the electrolytic capacitor based on the voltage wave parameters, and determine an initial voltage wave equation, an input power equation, and a discharge current equation of the electrolytic capacitor based on the voltage waveform periodic characteristics.

[0059] The voltage wave periodic characteristics can be understood as periodic characteristics corresponding to the voltage waveform changes at both ends of the electrolytic capacitor based on monitoring over a period of time.

[0060] In the present application, when monitoring the voltage wave parameters input by the AC input source and rectified by the rectifier bridge, in actual implementation, the voltage fluctuation at both ends of the switching power supply circuit can be monitored when the switching power supply circuit includes an electrolytic capacitor; and the voltage fluctuation at both ends of the switching power supply circuit can be monitored when the switching power supply circuit does not include an electrolytic capacitor, that is, the influence of the charging and discharging characteristics of the electrolytic capacitor on the change of the electrical parameters of the switching power supply circuit is not considered. Based on the difference in voltage wave parameters in the two cases, the voltage wave periodic characteristics for the electrolytic capacitor and the initial voltage wave equation for the electrolytic capacitor determined subsequently can be accurately determined.

[0061] For reference Figure 4 , Figure 4 is a schematic diagram of a voltage waveform in the implementation of this application. It should be noted that Figure 4 The dotted line portion is the voltage waveform monitored for the second case mentioned above, that is, the waveform diagram excludes the influence of the electrical characteristics of the electrolytic capacitor in the switching power supply circuit. Furthermore, in actual implementation, the impedance between the busbars at both ends of the electrolytic capacitor from the AC input source is very small and can usually be ignored.

[0062] Based on the monitored voltage wave parameters input from the AC input source and rectified by the rectifier bridge, such as Figure 4 The voltage waveform period characteristics of the electrolytic capacitor can be fed back, such as a sine curve Figure 4 The voltage waveform in is quantified, and the periodic characteristics of the voltage waveform may at least include the amplitude A, phase (ωx+φ), initial phase φ, offset k, and angular velocity ω, etc., which reflect the periodic changes of the electrolytic capacitor.

[0063] The initial voltage wave equation for the electrolytic capacitor can be determined by mathematical quantification, where the initial voltage wave equation is as follows (Formula 1.1.1):

[0064]

[0065] Among them, V ac is the AC voltage value of the AC input source, F ac is the AC operating frequency of the AC input source, t is the time parameter, V b(t) is the voltage parameter of the electrolytic capacitor (the charging and discharging effect of the electrolytic capacitor is not considered at this time).

[0066] In addition, in the above formula The purpose is to convert the sine waveform into a cosine waveform for subsequent mathematical analysis and processing.

[0067] For reference Figure 5 , Figure 5 is a schematic diagram of another voltage waveform in the implementation of this application. It should be noted that Figure 5 The dotted line portion is the voltage waveform monitored for the second case mentioned above, and the solid line portion is the voltage waveform corresponding to the influence of the electrical characteristics of the electrolytic capacitor in the switching power supply circuit. Furthermore, in actual implementation, the impedance between the busbars at both ends of the electrolytic capacitor from the AC input source AC is very small and can usually be ignored.

[0068] See also Figure 5 It can be seen that during the time from 0 to t1, the voltage is a monotonically decreasing waveform, and during the time from t1 to T, V b (t) voltage is the voltage after passing through the rectifier bridge, where T = 1 / 2F ac .

[0069] Based on the voltage waveform cycle characteristics, it can be known that: for the time from 0 to t1, the electrolytic capacitor provides energy for the subsequent load (load devices, load circuits, load units, etc. of the non-switching power supply part of the electronic equipment), and its voltage continues to decrease. Assume that its discharge current is I b (t). Therefore, the following discharge current equation can be obtained (Formula 1.1.2):

[0070]

[0071] In the formula, C b is the electrolytic capacitor capacity, and the mathematical conversion of formula 1.1.2 can be obtained (formula 1.1.3):

[0072]

[0073] The following mathematical analysis is performed:

[0074] Multiply both sides of the equation 1.1.3 by V b (t) has (Formula 1.1.4):

[0075]

[0076] Integrating both sides of the equation 1.1.4 gives:

[0077]

[0078] Based on the cycle characteristics of the voltage waveform, the input power equation can be constructed as follows during the entire cycle (Equation 1.1.6):

[0079] P in =∫I b (t)·V b (t)·dt (Formula 1.1.6)

[0080] Among them, P in Where is the input power for the electrolytic capacitor, I b (t) is the discharge current, V b (t) is the voltage parameter of the electrolytic capacitor, and t is the time parameter.

[0081] After the above mathematical analysis, the electronic device has completed the determination of the initial voltage wave equation for the electrolytic capacitor based on the periodic characteristics of the voltage waveform:

[0082] Discharge current equation:

[0083] Enter the power equation:

[0084] S203: Determine a voltage wave model for the electrolytic capacitor according to an input power equation, a discharge current equation and the initial voltage wave equation of the electrolytic capacitor.

[0085] Specifically, the electronic device performs mathematical operations according to the input power equation and the discharge current equation of the electrolytic capacitor to obtain a first voltage sub-model corresponding to the electrolytic capacitor in the discharge state;

[0086] Wherein, the first voltage sub-model is:

[0087] Among them, the V b (t) is the voltage parameter of the electrolytic capacitor, V ac is the AC voltage value of the AC input source; P in is the input power of the electrolytic capacitor, C b is the electrolytic capacity parameter of the electrolytic capacitor, t is the time parameter, and t1 is the time point when the electrolytic capacitor is converted from the discharge state to the charge state;

[0088] The following is an explanation of the determination process of the first voltage sub-model:

[0089] Performing mathematical operations on (Equation 1.1.6) and (Equation 1.1.5), such as substituting (Equation 1.1.6) into (1.1.5), we can obtain:

[0090]

[0091] Where C is a constant. Further simplifying (Equation 1.1.7) yields the following equation about V b The formula of (t) is:

[0092]

[0093] According to formula 1.1.1, the voltage across the electrolytic capacitor in the initialization phase is Substituting mathematical analysis into (Formula 1.1.8), we get:

[0094] according to Figure 5 The voltage waveform shown in the figure can be used to determine when t = 0, V b (t) has a maximum value, so the first voltage sub-model can be obtained:

[0095]

[0096] Furthermore, the electronic device uses the initial voltage wave equation as a second voltage sub-model corresponding to the electrolytic capacitor in a charging state;

[0097] The second voltage sub-model is:

[0098] Among them, F ac is the AC operating frequency of the AC input source, T is the charge and discharge cycle of the electrolytic capacitor,

[0099] The details are as follows:

[0100] Through mathematical analysis, during the time t1-T, the rectifier bridge and other devices in the circuit charge the electrolytic capacitor, that is, the electrolytic capacitor is in the charging stage, and its charging equation is (Formula 1.1.1), that is, the initial voltage wave equation is used as the second voltage sub-model corresponding to the electrolytic capacitor in the charging state;

[0101] It can be deduced that within a period T, the first voltage sub-model and the second voltage sub-model are used as voltage wave models for the electrolytic capacitor;

[0102] V b The voltage wave model of (t) is:

[0103]

[0104] S204: acquiring charging and discharging characteristics and voltage waveform period characteristics for the electrolytic capacitor based on the voltage wave model, performing triangular fitting processing on the input current waveform based on the charging and discharging characteristics and the voltage waveform period characteristics, and obtaining an initial input current function for the switching power supply circuit;

[0105] In a specific implementation manner, the charge-discharge characteristics are the discharge time, voltage and other characteristics corresponding to the discharge state of the electrolytic capacitor and the charging time, voltage and other characteristics corresponding to the charging state of the electrolytic capacitor.

[0106] The voltage waveform periodic characteristics may at least include amplitude A, phase (ωx+φ), initial phase φ, offset k, angular velocity ω, and other characteristics reflecting the periodic changes of the electrolytic capacitor.

[0107] Determining an input current cycle characteristic for the switching power supply circuit based on the charge and discharge characteristics;

[0108] Specifically, based on the charge and discharge characteristics, for electrolytic capacitors, the time from 0 to t1 is the process of discharging the electrolytic capacitor, and the time from t1 to T is the process of charging the electrolytic capacitor. Therefore, for the charging current (i.e., the input current) I ac (t), only exists within the time period from t1 to T.

[0109] Based on the mathematical analysis of the voltage waveform periodic characteristics, it can be seen that the actual current waveform is usually similar to the voltage waveform. Since the charging current (i.e., input current) I ac (t) only exists within the time period of t1 to T. Based on this, the present application creatively performs triangular sine fitting processing on the input current waveform within the time period of t1-T.

[0110] The triangular sine fitting process is usually based on the sine fitting of the input current waveform within the time t1-T, such as Figure 6 As shown, Figure 6 This is a schematic diagram of an input current involved in the present application. For the input current waveform corresponding to the time t1~T, a triangular sine general formula y=Asin(ωx+φ) is constructed, where the amplitude is A, the phase is (ωx+φ), the initial phase is φ, the offset k and the angular velocity is ω; assuming that the maximum value of the input current is I acmax ,based on Figure 6 The waveform after triangular sine fitting shown in the figure can obtain the input current function for the electrolytic capacitor. At the same time, based on the current characteristics of the switching power supply circuit, it can be known that the input current function of the electrolytic capacitor is equivalent to the current in the switching power supply circuit. Based on this, the back-end power device of the switching power supply circuit in this application is mathematically analyzed. After determining the input current function of the electrolytic capacitor, the initial input current function for the switching power supply circuit can be obtained, wherein the initial input current function of the switching power supply circuit is as follows:

[0111]

[0112] Among them, I inac(t) is the input current parameter of the switching power supply circuit, t is the time parameter, is the charge and discharge cycle T of the electrolytic capacitor, t1 is the time point when the electrolytic capacitor is converted from the discharge state to the charge state, and I acmax is the maximum value of the input current parameter.

[0113] S205: Determine an average value of electrical parameters for the electrolytic capacitor based on the voltage wave model, and construct an electrolytic output power equation based on the average value of the electrical parameters and an average current parameter of the electrolytic capacitor.

[0114] The average value of the electrical parameter can be an average voltage. According to (Formula 1-1-11), the average voltage V for the electrolytic capacitor can be obtained by mathematical analysis. b-avg for:

[0115]

[0116] Wherein, Vb(t) is the voltage parameter of the electrolytic capacitor, and V b_avg is the average value of the electrical parameter;

[0117] The electrolytic output power equation can be expressed as the product of the average voltage of the electrolytic capacitor and the average current of the electrolytic capacitor, so the electrolytic output power equation is as follows:

[0118]

[0119] Among them, the P in output power for the electrolysis;

[0120] S206: Determine a circuit current parameter for the switching power supply circuit based on the initial input current function, the average value of the electrical parameters, and the electrolysis output power equation;

[0121] In a specific embodiment,

[0122] Based on the initial input current function, the average value of the electrical parameters and the electrolytic output power equation, the maximum input current value for the switching power supply circuit, the input current function corresponding to the initial input current function and the input current effective value can be determined;

[0123] In a specific implementation, mathematical fitting is performed on the initial input current function, the average value of the electrical parameters and the electrolysis output power equation to obtain the following equation, and then the maximum input current of the switching power supply circuit is obtained by solving the equation, where the following a is the actual current maximum value which is a constant.

[0124]

[0125] Furthermore, after determining the maximum input current value, the input current function corresponding to the initial input current function can be obtained based on the maximum input current value a, as follows:

[0126]

[0127] After determining the input current function, the effective value of the input current can be determined. The effective value of the input current can be obtained by the following formula:

[0128]

[0129] Among them, I inac_rms is the effective value of the input current.

[0130] S207: Determine device loss parameters for the switching power supply circuit based on the circuit current parameters.

[0131] Please refer to the next embodiment for details.

[0132] In addition, in order to better explain the execution steps of the method for determining the switching power supply circuit loss of the present solution in the embodiment of the present application, a specific application is given as an example below. It should be known to those skilled in the art that the embodiment of the present application is not limited, as follows:

[0133] Assuming that the electronic device contains a switching power supply circuit, the following known parameters in practical applications are defined:

[0134] Input power: P in =50.5W; Power efficiency: η=0.95; Input voltage: V ac =100V;

[0135] Power frequency: F ac =50Hz; electrolytic capacitor value: C b =85uF.

[0136] According to the known conditions and formula 1-1, the voltage function after the rectifier bridge is:

[0137]

[0138] According to (Formula 1.1.10):

[0139]

[0140] Because at time t1, the electrolysis voltage reaches its maximum value, so:

[0141] V b (t1) = V inac (t1)---Formula 2-2-3

[0142] The time t1 is obtained as:

[0143] t1=7.645×10 -3 s---Formula 2-2-4

[0144] Therefore, the voltage function on the electrolytic capacitor in a period T is:

[0145]

[0146] According to formula 1-2-2 and formula 2-2-5, the average voltage, maximum voltage and minimum voltage on the electrolytic capacitor are:

[0147]

[0148] V b_min =V inac (t1)=104.456V---Formula 2-2-7

[0149] V b_max =V inac (0)=141.421V---Formula 2-2-8

[0150] According to the average voltage, formula 1-2-1 and formula 1-2-3, I acmax The values ​​are:

[0151]

[0152] Then the input current function is:

[0153]

[0154] The effective value of the current is:

[0155]

[0156] In order to verify the theoretical value obtained by the switching power supply circuit loss determination method of the present application, the actual value in the actual environment is measured and compared with the theoretical value obtained by the electronic device executing the "switching power supply circuit loss determination method" to verify the effectiveness of the switching power supply circuit loss determination method of the present application in quantifying the loss in the actual application environment. As follows: Figure 7 The input voltage, input current and bus voltage waveform corresponding to the switching power supply circuit loss determination method of the present application are shown under the condition of ignoring the electrolytic capacitor. Figure 7 The dotted line is the input voltage waveform without electrolytic capacitor; the solid curve is the voltage function waveform on the electrolytic capacitor (considering the electrolytic capacitor); and the long dashed line is the input current waveform at the front end of the electrolytic capacitor.

[0157] Table 1 gives the comparison between theoretical values ​​and measured values, the details are as follows:

[0158]

[0159] Based on the above comparison, it is shown that the errors of the electrical parameter values ​​calculated by the method for determining the switching power supply circuit loss of the electronic device are all within the engineering design range, which can meet the high requirements of actual engineering use, thereby realizing the accurate quantification of the electrical parameters of the switching power supply circuit in a complex AC environment, overcoming the complexity and uncertainty of the real-time working state of the circuit, and realizing the theoretical calculation of irregular parameters such as current and voltage in the circuit, simplifying the difficulty of calculating the switching power supply circuit loss.

[0160] In an embodiment of the present application, the electronic device monitors the voltage wave parameters input by the AC input source and rectified by the rectifier bridge, and determines the voltage wave model for the electrolytic capacitor based on the voltage wave parameters, and the electrolytic capacitor is connected to the two ends of the rectifier bridge; then, based on the electrical parameter characteristics corresponding to the voltage wave model, an initial input current function for the switching power supply circuit is constructed, and then based on the voltage wave model and the initial input current function, the electrical parameter average value and the electrolytic output power equation for the electrolytic capacitor are determined; then, based on the initial input current function, the electrical parameter average value and the electrolytic output power equation, the circuit current parameters for the switching power supply circuit are determined; finally, based on the circuit current parameters, the device loss parameters for the switching power supply circuit are determined. By first quantifying the working electrical parameters of the electrolytic capacitor device at the back end of the circuit to determine the input current in the circuit, and then determining the loss of the power device in the circuit, the loss calculation of the corresponding scenario of complex circuit state such as switching power supply circuit is realized, the loss uncertainty existing in the switching power supply circuit in the actual application environment is overcome, the loss quantification and current quantification of the complex circuit are realized, and the accuracy of loss monitoring is ensured; and, in some embodiments, for the case of irregular input current, a trigonometric sine equivalent method is used for calculation, which simplifies the calculation difficulty, and the error is small through actual comparison verification, thereby improving the accuracy of loss quantification; and, in some embodiments, for devices such as semiconductor rectifier bridges, a temperature coefficient is creatively introduced into the switching power supply circuit to reflect the state of the device at various working temperatures, thereby realizing the loss calculation of the device at different working temperatures.

[0161] See also Figure 8 , Figure 8 This is a flow chart of another embodiment of a method for determining the loss of a switching power supply circuit proposed in this application. Specifically:

[0162] S301: monitoring voltage wave parameters inputted by an AC input source and rectified by the rectifier bridge, and determining a voltage wave model for the electrolytic capacitor based on the voltage wave parameters, wherein the electrolytic capacitor is connected to both ends of the rectifier bridge;

[0163] S302: constructing an initial input current function for the switching power supply circuit based on the electrical parameter characteristics corresponding to the voltage wave model, and determining an electrical parameter average value and an electrolytic output power equation for the electrolytic capacitor based on the voltage wave model and the initial input current function;

[0164] S303: Determine a circuit current parameter for the switching power supply circuit based on the initial input current function, the average value of the electrical parameters, and the electrolysis output power equation;

[0165] S304: Determine a first loss parameter for the switching power supply circuit based on the circuit current parameter, where the first loss parameter is a loss value of the thermistor in the switching power supply circuit;

[0166] In a specific embodiment:

[0167] S3041: Determine a temperature-resistance model for the thermistor using a temperature-resistance curve fitting strategy.

[0168] In practical applications, a temperature resistance change curve for the thermistor can be obtained, and the temperature resistance change curve provides feedback on the resistance change of the thermistor as the temperature changes. Fig. 9 As stated, Fig. 9 is a schematic diagram of a temperature resistance change curve involved in this application. Fig. 9 The corresponding relationship between thermistor resistance and temperature change curve is shown in FIG.

[0169] In the present application, the electronic device may adopt a preset curve fitting formula and determine a temperature resistance model for the thermistor based on a preset number of temperature resistance sampling pairs indicated in the temperature resistance variation curve;

[0170] Among them, a preset curve fitting formula is used to fit the nonlinear temperature resistance change curve, so as to quantify the law of resistance change with temperature. Therefore, when calculating the loss of the switching power supply circuit, the actual temperature can be introduced into the loss calculation, further improving the accuracy of the loss calculation.

[0171] The preset curve fitting formula is:

[0172] in

[0173] The R ntcis the resistance value of the thermistor at the actual working temperature, temp is the actual working temperature of the thermistor, A, B, and C are three constant coefficients, and the three constant coefficients "A, B, and C" are determined based on the temperature-resistance sampling pairs indicated by the preset number.

[0174] The specified number is a value greater than 3, and three or more temperature-resistance sampling pairs can be taken to determine the three constant coefficients "A, B, C" for the thermistor.

[0175] The temperature-resistance sampling pair is a sampling point on the temperature-resistance curve, and the sampling point can represent the resistance of the corresponding thermistor at the current sampling temperature.

[0176] For example, Fig. 9 For example, three sampling points can be taken from the temperature-resistance curve to obtain three temperature-resistance sampling pairs, such as: (10, 2); (80, 0.2); (-10, 4) and then the degrees Celsius are converted to Kelvin. The three sampling pairs are substituted into the above formula to obtain the three constant coefficients of "A, B, C".

[0177] S3042: The electronic device may determine an actual resistance value of the thermistor at an actual circuit operating temperature based on the temperature resistance model;

[0178] In practical applications, after measuring the current actual circuit operating temperature, the actual resistance value of the thermistor can be obtained by inputting it into the above-mentioned temperature resistance model.

[0179] S3043: Determine a first loss parameter for the switching power supply circuit based on the actual resistance value and the circuit current parameter.

[0180] The first loss parameter can be calculated by the following formula:

[0181]

[0182] Among them, P ntc is the first loss parameter, R ntc is the actual resistance value, I inac-rms is the circuit current parameter.

[0183] Assuming that the actual operating temperature of the circuit is 373 Kelvin (100 degrees Celsius), the resistance value at 373 Kelvin is Temp = 373, and input into formula 1.3.2 to get Rntc (373) at this temperature, and then use this value to calculate its loss. The loss of the thermistor is the product of the square of the effective value of the input current and the resistance value.

[0184] S305: Determine a second loss parameter for the switching power supply circuit based on the circuit current parameter, where the second loss parameter is a loss value of the common-mode inductor in the switching power supply circuit;

[0185] In a feasible implementation manner, 1. The electronic device obtains the DC resistance value and the actual operating temperature of the common mode inductor, and determines the temperature resistance equivalent coefficient based on the actual operating temperature;

[0186] For common mode inductors, the resistance value R at room temperature can usually be obtained. LCB_dc , which is the resistance of the DC component of the common-mode inductor. Due to the symmetry of the common-mode inductor, the common-mode inductor will basically not generate AC loss or the AC loss is small during operation. Therefore, when determining the loss of the common-mode inductor, only the loss caused by the DC component can be considered.

[0187] 2. Determine a DC resistance value for the common mode inductor based on the DC resistance value and the temperature resistance coefficient, and determine a second loss parameter for the switching power supply circuit based on the DC resistance value and the circuit current parameter.

[0188] In addition, in actual working process, the common mode inductor works at high temperature, and the electronic equipment can obtain the temperature resistance coefficient between the high temperature equivalent resistance and the room temperature equivalent resistance of the copper wire in the common mode inductor, and set this temperature resistance coefficient as k.

[0189]

[0190] It is worth noting that the above coefficient formula is applicable to calculating the DC equivalent resistance value of general copper wire at high temperature.

[0191] Wherein, Temp_a is the temperature at high temperature (eg, 100 degrees Celsius); Temp_b is the temperature at normal temperature (eg, 25 degrees Celsius).

[0192] The DC resistance value of the copper wire of the common mode inductor under Temp_a can be expressed as:

[0193] R LCB_dc_a =2·k·R LCB_dc ---Formula 1-4-2

[0194] The number 2 in the above formula represents that the common-mode inductor has two copper wire windings, which are in a series relationship in the LN line loop, so its impedance is twice.

[0195] Electronic devices are based on the DC resistance value R LCB_dc_a The second loss parameter for the switching power supply circuit is determined by the circuit current parameter, and the second loss parameter can be calculated by the following formula:

[0196]

[0197] S306: Determine a third loss parameter for the switching power supply circuit based on the circuit current parameter, wherein the third loss parameter is a loss value of the rectifier bridge in the switching power supply circuit.

[0198] In a feasible implementation, 1. The electronic device may equate the power consumption corresponding to the rectifier bridge to the power consumption of a specified number of diodes, and determine a conduction mapping relationship between the conduction voltage of the diode, the actual operating temperature and the circuit current parameter;

[0199] 2. The electronic device then obtains a loss model for the diode, and determines a third loss parameter for the rectifier bridge based on the loss model and the conduction mapping relationship.

[0200] In practical applications, the rectifier bridge can be equivalent to a specified number (such as 4) of diodes, and the loss of the rectifier bridge can be equivalent to the sum of the specified number (such as 4) of diodes, based on the characteristics of the rectifier diode: the sinusoidal AC voltage input by the input source is usually converted into a positive "mantou wave", so in the first half of the power frequency cycle, the rectifier bridge usually only has two diodes working, and the current only flows through these two diodes. In the second half of the power frequency cycle, the input sinusoidal voltage is negative, and current flows through the other two diodes.

[0201] For half a power frequency cycle, the loss of a single diode can be determined using the following formula:

[0202]

[0203] Then in one power frequency cycle, the loss of the rectifier bridge is the sum of the losses of the four diodes, so the loss of the entire rectifier bridge is twice that of the four diodes. The loss of the rectifier bridge can be expressed as:

[0204] P _bridge =4*P bri ---Formula 1-5-2

[0205] Among them, P bri is the power loss of the diode, P _bridge is the loss value of the rectifier bridge.

[0206] The relationship between the on-state current and the on-state mapping.

[0207] The process of determining the conduction mapping relationship is as follows:

[0208] The mapping relationship between the diode conduction voltage and conduction current can be obtained through electronic equipment testing, that is, obtaining the VF / IF characteristics. In this application, it is considered that the relationship between VF / IF is greatly affected by temperature. Therefore, in order to accurately calculate the loss of power consumption devices at different temperatures, this application introduces the concept of temperature coefficient for diode conduction in the process of determining diode conduction. By introducing temperature coefficients for semiconductor earphone tube devices to quantify the temperature impact in complex circuit environments, the working state of the device at different temperatures is quantified, and the loss determination of the rectifier bridge at different temperatures can be realized.

[0209] The specific method is as follows:

[0210] Determine a mean on-voltage value for at least one of the actual operating temperatures based on the on-map relationship, and determine a on-temperature coefficient function based on each of the actual operating temperatures and the mean on-voltage value;

[0211] The conduction mapping relationship can be quantified based on a curve of temperature and conduction voltage corresponding to the VF / IF characteristic of the diode.

[0212] like Fig.10 As shown, Fig.10 The VF / IF fitting curve of a diode at 60 degrees, 80 degrees, 100 degrees, and 120 degrees is shown. According to the fitting curve, the VF value at any current IF at the four temperatures can be determined, such as Fig.11 As shown, Fig.11 is a schematic diagram of temperature and on-state voltage involved in this application, Fig.11 The on-state voltage values ​​corresponding to different on-state currents at different actual operating temperatures are shown in FIG.

[0213] Indicatively, taking 60 degrees as a reference temperature, for example, the on-state voltage drop at each current can be divided by the on-state voltage drop at 60 degrees to obtain Fig.12 Finally, the values ​​at each temperature are averaged.

[0214] Finally, by fitting the curve with Tc (temperature) as the horizontal coordinate and AVG (average on-state voltage) as the vertical coordinate, we can get the temperature coefficient curve, such as Fig.13 As shown, Fig.13 It is a schematic diagram of the temperature coefficient curve of the rectifier bridge in this application.

[0215] Its temperature coefficient function is:

[0216] K bridge (temp) = a·temp 2 -b·temp+c, ---Formula 1-5-2

[0217] Wherein, temp is the actual working temperature, K bridge (temp) is the conduction temperature coefficient, a, b, c are preset constants;

[0218] For example, Fig.13 The corresponding temperature coefficient function can be determined as follows:

[0219] K bridge (temp)=1.2482·10 -5 ·temp 2 -4.2523·10 -3 ·temp+1.064---Formula 1-5-2

[0220] The on-state temperature coefficient function can be determined through the above, and the determination process can be as follows: 1. Determine the on-state voltage mean value for at least one of the actual operating temperatures, and then determine the on-state temperature coefficient function based on each of the actual operating temperatures and the on-state voltage mean value;

[0221] Specifically, a third loss parameter for the rectifier bridge is determined based on the conduction temperature coefficient function, the loss model, and the specified number; wherein,

[0222] The loss model is:

[0223] The P bri is the power loss of the diode, the F ac is the AC operating frequency of the AC input source, the V bri (t) is the conduction voltage of the diode, and the I inac(t) is the input current parameter of the switching power supply circuit, K bridge (temp) is the on-state temperature coefficient.

[0224] Indicatively, Figure 11-13 Take the parameters in the actual application environment as an example.

[0225] The diode conduction voltage function expression is the expression at 60 degrees, that is, the loss model should be:

[0226]

[0227] Then the third loss parameter for the rectifier bridge can be expressed as:

[0228] P _bridge =4*P bri ---Formula 1-5-5

[0229] In an embodiment of the present application, the electronic device monitors the voltage wave parameters input by the AC input source and rectified by the rectifier bridge, and determines the voltage wave model for the electrolytic capacitor based on the voltage wave parameters, and the electrolytic capacitor is connected to the two ends of the rectifier bridge; then, based on the electrical parameter characteristics corresponding to the voltage wave model, an initial input current function for the switching power supply circuit is constructed, and then based on the voltage wave model and the initial input current function, the electrical parameter average value and the electrolytic output power equation for the electrolytic capacitor are determined; then, based on the initial input current function, the electrical parameter average value and the electrolytic output power equation, the circuit current parameters for the switching power supply circuit are determined; finally, based on the circuit current parameters, the device loss parameters for the switching power supply circuit are determined. By first quantifying the working electrical parameters of the electrolytic capacitor device at the back end of the circuit to determine the input current in the circuit, and then determining the loss of the power device in the circuit, the loss calculation of the corresponding scenario of complex circuit state such as switching power supply circuit is realized, the loss uncertainty existing in the switching power supply circuit in the actual application environment is overcome, the loss quantification and current quantification of the complex circuit are realized, and the accuracy of loss monitoring is ensured; and, in some embodiments, for the case of irregular input current, a trigonometric sine equivalent method is used for calculation, which simplifies the calculation difficulty, and the error is small through actual comparison verification, thereby improving the accuracy of loss quantification; and, in some embodiments, for devices such as semiconductor rectifier bridges, a temperature coefficient is creatively introduced into the switching power supply circuit to reflect the state of the device at various working temperatures, thereby realizing the loss calculation of the device at different working temperatures.

[0230] The following will be combined Fig.14 , the switching power supply circuit loss determination device provided in the embodiment of the present application is introduced in detail. It should be noted that, Fig.14 The switching power supply circuit loss determination device shown is used to implement the present application Figures 1 to 13 For the convenience of explanation, only the part related to the embodiment of the present application is shown. For the specific technical details not disclosed, please refer to the present application. Figures 1 to 13 The embodiment shown.

[0231] See also Fig.14 , which shows a schematic diagram of the structure of a switching power supply circuit loss determination device according to an embodiment of the present application. The switching power supply circuit loss determination device 1 can be implemented as all or part of a user terminal through software, hardware, or a combination of both. According to some embodiments, the switching power supply circuit loss determination device 1 includes a voltage wave model determination module 11, an electric parameter power determination module 12, a current parameter determination module 13, and a device loss determination module 14, which are specifically used to:

[0232] The switching power supply circuit includes an AC input source, a thermistor, a capacitor, a common-mode inductor, a rectifier bridge and an electrolytic capacitor.

[0233] A voltage wave model determination module 11 is used to monitor the voltage wave parameters input by the AC input source and rectified by the rectifier bridge, and determine the voltage wave model for the electrolytic capacitor based on the voltage wave parameters, wherein the electrolytic capacitor is connected to both ends of the rectifier bridge;

[0234] An electrical parameter power determination module 12, configured to construct an initial input current function for the switching power supply circuit based on electrical parameter characteristics corresponding to the voltage wave model, and determine an electrical parameter average value and an electrolytic output power equation for the electrolytic capacitor based on the voltage wave model and the initial input current function;

[0235] A current parameter determination module 13, configured to determine a circuit current parameter for the switching power supply circuit based on the initial input current function, the average value of the electric parameter and the electrolysis output power equation;

[0236] The device loss determination module 14 is used to determine the device loss parameters for the switching power supply circuit based on the circuit current parameters.

[0237] Optionally, the voltage wave model determination module 11 is specifically used to:

[0238] Determine a voltage waveform periodic characteristic for the electrolytic capacitor based on the voltage wave parameter, and determine an initial voltage wave equation, an input power equation, and a discharge current equation of the electrolytic capacitor based on the voltage waveform periodic characteristic;

[0239] A voltage wave model for the electrolytic capacitor is determined according to an input power equation, a discharge current equation and the initial voltage wave equation of the electrolytic capacitor.

[0240] Optionally, the voltage wave model determination module 11 is specifically used to:

[0241] Perform mathematical operations on the input power equation and the discharge current equation of the electrolytic capacitor to obtain a first voltage sub-model corresponding to the electrolytic capacitor in the discharge state;

[0242] Using the initial voltage wave equation as a second voltage sub-model corresponding to the electrolytic capacitor in a charging state;

[0243] Using the first voltage sub-model and the second voltage sub-model as voltage wave models for the electrolytic capacitor;

[0244] Wherein, the first voltage sub-model is:

[0245] Among them, the Vb (t) is the voltage parameter of the electrolytic capacitor, V ac is the AC voltage value of the AC input source; P in is the input power of the electrolytic capacitor, C b is the electrolytic capacity parameter of the electrolytic capacitor, t is the time parameter, and t1 is the time point when the electrolytic capacitor is converted from the discharge state to the charge state;

[0246] The second voltage sub-model is:

[0247] Among them, F ac is the AC operating frequency of the AC input source, T is the charge and discharge cycle of the electrolytic capacitor,

[0248] Optionally, the electrical parameter power determination module 12 is specifically used to:

[0249] Based on the voltage wave model, the charge and discharge characteristics and the voltage waveform period characteristics of the electrolytic capacitor are acquired, and based on the charge and discharge characteristics and the voltage waveform period characteristics, a triangular fitting process is performed on the input current waveform to obtain an initial input current function for the switching power supply circuit;

[0250] An average value of electrical parameters for the electrolytic capacitor is determined based on the voltage wave model, and an electrolytic output power equation is constructed based on the average value of the electrical parameters and an average current parameter of the electrolytic capacitor.

[0251] Optionally, the electrical parameter power determination module 12 is specifically used to:

[0252] Determine the input current cycle characteristics for the switching power supply circuit based on the charging and discharging characteristics, and perform triangular sine fitting processing on the input current waveform based on the voltage waveform cycle characteristics and the input current cycle characteristics to obtain an initial input current function for the switching power supply circuit;

[0253] Wherein, the initial input current function includes:

[0254]

[0255] Among them, I inac(t) is the input current parameter of the switching power supply circuit, t is the time parameter, is the charge and discharge cycle T of the electrolytic capacitor, t1 is the time point when the electrolytic capacitor is converted from the discharge state to the charge state, and I acmax is the maximum value of the input current parameter.

[0256] Optionally, the current parameter determination module 13 is specifically used for:

[0257] Based on the initial input current function, the average value of the electrical parameters and the electrolysis output power equation, determining the maximum input current of the switching power supply circuit, the input current function corresponding to the initial input current function and the input current effective value;

[0258] Among them, the average value of the electrical parameters is: Among them, the V b (t) is the voltage parameter of the electrolytic capacitor, and V b_avg is the average value of the electrical parameter;

[0259] Wherein, the electrolysis output power equation is: Among them, the P in output power for the electrolysis;

[0260] Wherein, the effective value of the input current is: I inac_rms is the effective value of the input current.

[0261] Optionally, the device loss determination module 14 is specifically configured to:

[0262] Determine a first loss parameter for the switching power supply circuit based on the circuit current parameter, wherein the first loss parameter is a loss value of the thermistor in the switching power supply circuit; and / or,

[0263] determining a second loss parameter for the switching power supply circuit based on the circuit current parameter, wherein the second loss parameter is a loss value of the common-mode inductor in the switching power supply circuit; and / or,

[0264] A third loss parameter for the switching power supply circuit is determined based on the circuit current parameter, wherein the third loss parameter is a loss value of the rectifier bridge in the switching power supply circuit.

[0265] Optionally, the device loss determination module 14 is specifically configured to:

[0266] Determine a temperature resistance model for the thermistor by using a temperature resistance curve fitting strategy;

[0267] Determine an actual resistance value of the thermistor at an actual circuit operating temperature based on the temperature resistance model;

[0268] A first loss parameter for the switching power supply circuit is determined based on the actual resistance value and the circuit current parameter.

[0269] Optionally, the device loss determination module 14 is specifically configured to:

[0270] Obtaining a temperature-resistance variation curve for the thermistor, and determining a temperature-resistance model for the thermistor using a preset curve fitting formula and based on a preset number of temperature-resistance sampling pairs indicated in the temperature-resistance variation curve;

[0271] The preset curve fitting formula is:

[0272] in

[0273] The R ntc is the resistance value of the thermistor at the actual working temperature, temp is the actual working temperature of the thermistor, A, B, and C are three constant coefficients, and the three constant coefficients "A, B, and C" are determined based on the temperature-resistance sampling pairs indicated by the preset number.

[0274] Optionally, the device loss determination module 14 is specifically configured to:

[0275] Acquire the DC resistance value and the actual operating temperature of the common mode inductor, and determine the temperature resistance equivalent coefficient based on the actual operating temperature;

[0276] A DC resistance value for the common mode inductor is determined based on the DC resistance value and the temperature resistance coefficient, and a second loss parameter for the switching power supply circuit is determined based on the DC resistance and the circuit current parameter.

[0277] Optionally, the device loss determination module 14 is specifically configured to:

[0278] Equivalent the power loss corresponding to the rectifier bridge to the power loss of a specified number of diodes, and determining a conduction mapping relationship between the conduction voltage, actual operating temperature and the circuit current parameter of the diode;

[0279] A loss model for the diode is obtained, and a third loss parameter for the rectifier bridge is determined based on the loss model and the conduction mapping relationship.

[0280] Optionally, the device loss determination module 14 is specifically configured to:

[0281] Determine a mean on-voltage value for at least one of the actual operating temperatures based on the on-map relationship, and determine a on-temperature coefficient function based on each of the actual operating temperatures and the mean on-voltage value;

[0282] Determine a third loss parameter for the rectifier bridge based on the conduction temperature coefficient function, the loss model, and the specified quantity; wherein,

[0283] The on-state temperature coefficient function is:

[0284] K bridge (temp) = a·temp 2 -b·temp+c, where temp is the actual working temperature, K bridge (temp) is the conduction temperature coefficient, a, b, c are preset constants;

[0285] The loss model is:

[0286] The P bri is the power loss of the diode, the F ac is the AC operating frequency of the AC input source, the V bri (t) is the conduction voltage of the diode, and the I inac(t) is the input current parameter of the switching power supply circuit. It should be noted that the switching power supply circuit loss determination device provided in the above embodiment only uses the division of the above functional modules as an example when executing the switching power supply circuit loss determination method. In actual applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above. In addition, the switching power supply circuit loss determination device provided in the above embodiment and the switching power supply circuit loss determination method embodiment belong to the same concept, and the implementation process thereof is detailed in the method embodiment, which will not be repeated here.

[0287] The serial numbers of the above-mentioned embodiments of the present application are for description only and do not represent the advantages or disadvantages of the embodiments.

[0288] The present application also provides a computer storage medium, which can store multiple instructions, and the instructions are suitable for being loaded and executed by a processor as described above. Figures 1 to 13 The switching power supply circuit loss determination method of the embodiment shown in the figure can be specifically implemented by referring to Figures 1 to 13 The specific description of the illustrated embodiment will not be repeated here.

[0289] The present application also provides a computer program product, which stores at least one instruction, and the at least one instruction is loaded and executed by the processor as described above. Figures 1 to 13 The switching power supply circuit loss determination method of the embodiment shown in the figure can be specifically implemented by referring to Figures 1 to 13 The specific description of the illustrated embodiment will not be repeated here.

[0290] See also Fig.15 , which is a schematic diagram of the structure of a first terminal according to an embodiment of the present application. Fig.15As shown, the first terminal 1000 may include: at least one processor 1001 , at least one network interface 1004 , a user interface 1003 , a memory 1005 , and at least one communication bus 1002 .

[0291] The communication bus 1002 is used to realize the connection and communication between these components.

[0292] The user interface 1003 may include a display screen (Display) and a camera (Camera), and the optional user interface 1003 may also include a standard wired interface and a wireless interface.

[0293] The network interface 1004 may optionally include a standard wired interface or a wireless interface (such as a WI-FI interface).

[0294] Among them, the processor 1001 may include one or more processing cores. The processor 1001 uses various interfaces and lines to connect various parts within the entire server 1000, and executes various functions and processes data of the server 1000 by running or executing instructions, programs, code sets or instruction sets stored in the memory 1005, and calling data stored in the memory 1005. Optionally, the processor 1001 can be implemented in at least one hardware form of digital signal processing (Digital Signal Processing, DSP), field programmable gate array (Field-Programmable Gate Array, FPGA), and programmable logic array (Programmable Logic Array, PLA). The processor 1001 can integrate one or a combination of a central processing unit (Central Processing Unit, CPU), a graphics processing unit (Graphics Processing Unit, GPU) and a modem. Among them, the CPU mainly processes the operating system, user interface and application programs; the GPU is responsible for rendering and drawing the content to be displayed on the display screen; the modem is used to process wireless communications. It can be understood that the above-mentioned modem may not be integrated into the processor 1001, and it can be implemented separately through a chip.

[0295] Among them, the memory 1005 may include a random access memory (Random Access Memory, RAM) and may also include a read-only memory (Read-Only Memory). Optionally, the memory 1005 includes a non-transitory computer-readable storage medium. The memory 1005 can be used to store instructions, programs, codes, code sets or instruction sets. The memory 1005 may include a program storage area and a data storage area, wherein the program storage area may store instructions for implementing an operating system, instructions for at least one function (such as a touch function, a sound playback function, an image playback function, etc.), instructions for implementing the above-mentioned various method embodiments, etc.; the data storage area may store data involved in the above-mentioned various method embodiments, etc. The memory 1005 may optionally be at least one storage device located away from the aforementioned processor 1001. As Fig.15 As shown, the memory 1005 as a computer storage medium may include an operating system, a network communication module, a user interface module, and a switching power supply circuit loss determination program.

[0296] In the embodiment of the present application, the execution subject of each step may be the electronic device described above. Optionally, the execution subject of each step is the operating system of the electronic device. The operating system may be an Android system, an IOS system, or other operating systems, which is not limited in the embodiment of the present application.

[0297] The electronic device of the embodiment of the present application may also be equipped with a display device, which may be any device capable of realizing a display function, such as a cathode ray tube display (CR), a light-emitting diode display (LED), an electronic ink screen, a liquid crystal display (LCD), a plasma display panel (PDP), etc. The user may use the display device on the electronic device 101 to view displayed text, images, videos and other information. The electronic device may be a smart phone, a tablet computer, a gaming device, an AR (Augmented Reality) device, a car, a data storage device, an audio playback device, a video playback device, a notebook, a desktop computing device, a wearable device such as an electronic watch, an electronic glasses, an electronic helmet, an electronic bracelet, an electronic necklace, electronic clothing and other devices.

[0298] exist Fig.15In the electronic device shown, the processor 1001 can be used to call the application stored in the memory 1005 and specifically perform the following operations:

[0299] monitoring a voltage wave parameter inputted by an AC input source and rectified by the rectifier bridge, and determining a voltage wave model for the electrolytic capacitor based on the voltage wave parameter, wherein the electrolytic capacitor is connected to both ends of the rectifier bridge;

[0300] Constructing an initial input current function for the switching power supply circuit based on the electrical parameter characteristics corresponding to the voltage wave model, and determining an electrical parameter average value and an electrolytic output power equation for the electrolytic capacitor based on the voltage wave model and the initial input current function;

[0301] Determining circuit current parameters for the switching power supply circuit based on the initial input current function, the average value of the electrical parameters, and the electrolysis output power equation;

[0302] A device loss parameter for the switching power supply circuit is determined based on the circuit current parameter.

[0303] In one embodiment, when the processor 1001 determines the voltage wave model for the electrolytic capacitor based on the voltage wave parameter, the processor 1001 specifically performs the following operations:

[0304] Determine a voltage waveform periodic characteristic for the electrolytic capacitor based on the voltage wave parameter, and determine an initial voltage wave equation, an input power equation, and a discharge current equation of the electrolytic capacitor based on the voltage waveform periodic characteristic;

[0305] A voltage wave model for the electrolytic capacitor is determined according to an input power equation, a discharge current equation and the initial voltage wave equation of the electrolytic capacitor.

[0306] In one embodiment, when the processor 1001 determines the voltage wave model for the electrolytic capacitor based on the voltage wave parameter, the processor 1001 specifically performs the following operations:

[0307] Determining a voltage wave model for the electrolytic capacitor according to an input power equation, a discharge current equation, and the initial voltage wave equation of the electrolytic capacitor includes:

[0308] Perform mathematical operations on the input power equation and the discharge current equation of the electrolytic capacitor to obtain a first voltage sub-model corresponding to the electrolytic capacitor in the discharge state;

[0309] Using the initial voltage wave equation as a second voltage sub-model corresponding to the electrolytic capacitor in a charging state;

[0310] Using the first voltage sub-model and the second voltage sub-model as voltage wave models for the electrolytic capacitor;

[0311] Wherein, the first voltage sub-model is:

[0312] Among them, the V b (t) is the voltage parameter of the electrolytic capacitor, V ac is the AC voltage value of the AC input source; P in is the input power of the electrolytic capacitor, C b is the electrolytic capacity parameter of the electrolytic capacitor, t is the time parameter, and t1 is the time point when the electrolytic capacitor is converted from the discharge state to the charge state;

[0313] The second voltage sub-model is:

[0314] Among them, F ac is the AC operating frequency of the AC input source, T is the charge and discharge cycle of the electrolytic capacitor,

[0315] In one embodiment, the processor 1001 executes the construction of an initial input current function for the switching power supply circuit based on the electrical parameter characteristics corresponding to the voltage wave model, and determines the electrical parameter average value and the electrolytic output power equation for the electrolytic capacitor based on the voltage wave model and the initial input current function, including:

[0316] Based on the voltage wave model, the charge and discharge characteristics and the voltage waveform period characteristics of the electrolytic capacitor are acquired, and based on the charge and discharge characteristics and the voltage waveform period characteristics, a triangular fitting process is performed on the input current waveform to obtain an initial input current function for the switching power supply circuit;

[0317] An average value of electrical parameters for the electrolytic capacitor is determined based on the voltage wave model, and an electrolytic output power equation is constructed based on the average value of the electrical parameters and an average current parameter of the electrolytic capacitor.

[0318] In one embodiment, when the processor 1001 performs the triangular fitting process on the input current waveform based on the charge and discharge characteristics and the voltage waveform period characteristics to obtain the initial input current function for the switching power supply circuit, the processor 1001 specifically performs the following steps:

[0319] Determine the input current cycle characteristics for the switching power supply circuit based on the charging and discharging characteristics, and perform triangular sine fitting processing on the input current waveform based on the voltage waveform cycle characteristics and the input current cycle characteristics to obtain an initial input current function for the switching power supply circuit;

[0320] Wherein, when the initial current function is input, the following steps are specifically performed:

[0321]

[0322] Among them, I inac(t) is the input current parameter of the switching power supply circuit, t is the time parameter, is the charge and discharge cycle T of the electrolytic capacitor, t1 is the time point when the electrolytic capacitor is converted from the discharge state to the charge state, and I acmax is the maximum value of the input current parameter.

[0323] In one embodiment, the processor 1001 determines the circuit current parameter for the switching power supply circuit based on the initial input current function, the average value of the electrical parameter, and the electrolysis output power equation, including:

[0324] Based on the initial input current function, the average value of the electrical parameters and the electrolysis output power equation, determining the maximum input current of the switching power supply circuit, the input current function corresponding to the initial input current function and the input current effective value;

[0325] Among them, the average value of the electrical parameters is: Among them, the V b (t) is the voltage parameter of the electrolytic capacitor, and V b_avg is the average value of the electrical parameter;

[0326] Wherein, the electrolysis output power equation is: Among them, the P in output power for the electrolysis;

[0327] Wherein, the effective value of the input current is: I inac_rms is the effective value of the input current.

[0328] In one embodiment, when the processor 1001 determines the device loss parameter for the switching power supply circuit based on the circuit current parameter, the processor 1001 specifically performs the following steps:

[0329] Determine a first loss parameter for the switching power supply circuit based on the circuit current parameter, wherein the first loss parameter is a loss value of the thermistor in the switching power supply circuit; and / or,

[0330] determining a second loss parameter for the switching power supply circuit based on the circuit current parameter, wherein the second loss parameter is a loss value of the common-mode inductor in the switching power supply circuit; and / or,

[0331] A third loss parameter for the switching power supply circuit is determined based on the circuit current parameter, wherein the third loss parameter is a loss value of the rectifier bridge in the switching power supply circuit.

[0332] In one embodiment, when the processor 1001 determines the first loss parameter for the switching power supply circuit based on the circuit current parameter, the processor 1001 specifically performs the following steps:

[0333] Determine a temperature resistance model for the thermistor by using a temperature resistance curve fitting strategy;

[0334] Determine an actual resistance value of the thermistor at an actual circuit operating temperature based on the temperature resistance model;

[0335] A first loss parameter for the switching power supply circuit is determined based on the actual resistance value and the circuit current parameter.

[0336] In one embodiment, when the processor 1001 executes the temperature-resistance curve fitting strategy to determine the temperature-resistance model for the thermistor, the processor 1001 specifically performs the following steps:

[0337] Obtaining a temperature-resistance variation curve for the thermistor, and determining a temperature-resistance model for the thermistor using a preset curve fitting formula and based on a preset number of temperature-resistance sampling pairs indicated in the temperature-resistance variation curve;

[0338] The preset curve fitting formula is:

[0339] in

[0340] The R ntc is the resistance value of the thermistor at the actual working temperature, temp is the actual working temperature of the thermistor, A, B, and C are three constant coefficients, and the three constant coefficients "A, B, and C" are determined based on the temperature-resistance sampling pairs indicated by the preset number.

[0341] In one embodiment, when the processor 1001 determines the second loss parameter for the switching power supply circuit based on the circuit current parameter, the processor 1001 specifically performs the following steps:

[0342] Acquire the DC resistance value and the actual operating temperature of the common mode inductor, and determine the temperature resistance equivalent coefficient based on the actual operating temperature;

[0343] A DC resistance value for the common mode inductor is determined based on the DC resistance value and the temperature resistance coefficient, and a second loss parameter for the switching power supply circuit is determined based on the DC resistance and the circuit current parameter.

[0344] In one embodiment, when the processor 1001 determines the third loss parameter for the switching power supply circuit based on the circuit current parameter, the processor 1001 specifically performs the following steps:

[0345] Equivalent the power loss corresponding to the rectifier bridge to the power loss of a specified number of diodes, and determining a conduction mapping relationship between the conduction voltage, actual operating temperature and the circuit current parameter of the diode;

[0346] A loss model for the diode is obtained, and a third loss parameter for the rectifier bridge is determined based on the loss model and the conduction mapping relationship.

[0347] In one embodiment, when the processor 1001 determines the third loss parameter for the rectifier bridge based on the loss model and the conduction mapping relationship, it specifically performs the following steps:

[0348] Determine a mean on-voltage value for at least one of the actual operating temperatures based on the on-map relationship, and determine a on-temperature coefficient function based on each of the actual operating temperatures and the mean on-voltage value;

[0349] Determine a third loss parameter for the rectifier bridge based on the conduction temperature coefficient function, the loss model, and the specified quantity; wherein,

[0350] The on-state temperature coefficient function is:

[0351] K bridge (temp) = a·temp 2 -b·temp+c, where temp is the actual working temperature, K bridge (temp) is the conduction temperature coefficient, a, b, c are preset constants;

[0352] The loss model is:

[0353] The P bri is the power loss of the diode, the F ac is the AC operating frequency of the AC input source, the V bri (t) is the conduction voltage of the diode, and the I inac(t)is the input current parameter of the switching power supply circuit.

[0354] It should be noted that those skilled in the art can clearly understand that the technical solution of the present application can be implemented with the help of software and / or hardware. The "unit" and "module" in this specification refer to software and / or hardware that can independently complete or cooperate with other components to complete specific functions, where the hardware can be, for example, a field programmable gate array (FPGA), an integrated circuit (IC), etc.

[0355] For the aforementioned method embodiments, for the sake of simplicity, they are all described as a series of action combinations, but those skilled in the art should be aware that the present application is not limited by the order of the actions described, because according to the present application, some steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily required by the present application.

[0356] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0357] In the several embodiments provided in the present application, it should be understood that the disclosed devices can be implemented in other ways. For example, the device embodiments described above are only schematic, such as the division of the units, which is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some service interfaces, and the indirect coupling or communication connection of devices or units can be electrical or other forms.

[0358] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0359] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0360] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable memory. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a memory, including a number of instructions to enable a computer device (which can be a personal computer, server or network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned memory includes: U disk, read-only memory (ROM), random access memory (RAM), mobile hard disk, disk or optical disk and other media that can store program code.

[0361] A person skilled in the art may understand that all or part of the steps in the various methods of the above embodiments may be completed by entering a program to instruct the relevant hardware. The program may be stored in a computer-readable memory, and the memory may include: a flash drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, etc.

[0362] The above is only an exemplary embodiment of the present disclosure, and the scope of the present disclosure cannot be limited thereto. That is, any equivalent changes and modifications made according to the teachings of the present disclosure are still within the scope of the present disclosure. After considering the specification and practicing the disclosure here, those skilled in the art will easily think of other embodiments of the present disclosure. This application is intended to cover any modification, use or adaptation of the present disclosure, which follows the general principles of the present disclosure and includes common knowledge or customary technical means in the technical field not recorded in the present disclosure. The description and examples are only regarded as exemplary, and the scope and spirit of the present disclosure are defined by the claims.

Claims

1. A method for determining the circuit loss of a switching power supply, characterized in that: The switching power supply circuit includes an AC input source, a thermistor, a capacitor, a common-mode inductor, a rectifier bridge, and an electrolytic capacitor. The method comprises: Monitor the voltage wave parameters input by the AC input source and rectified by the rectifier bridge, the voltage wave parameters are the instantaneous change parameters of the voltage across the electrolytic capacitor, and determine the voltage wave model for the electrolytic capacitor based on the voltage wave parameters, the electrolytic capacitor is connected to the two ends of the rectifier bridge, and the voltage wave model is a numerical change model for time and voltage wave parameters; Constructing an initial input current function for the switching power supply circuit based on the electrical parameter characteristics corresponding to the voltage wave model, and determining an electrical parameter average value and an electrolytic output power equation for the electrolytic capacitor based on the voltage wave model and the initial input current function, wherein the electrical parameter characteristics include voltage fluctuation characteristics corresponding to the voltage wave model, and the electrical parameter average value includes an average voltage value and an average current value at both ends of the electrolytic capacitor; Determining circuit current parameters for the switching power supply circuit based on the initial input current function, the average value of the electrical parameters, and the electrolysis output power equation; A device loss parameter for the switching power supply circuit is determined based on the circuit current parameter.

2. The method according to claim 1, characterized in that: The determining of a voltage wave model for the electrolytic capacitor based on the voltage wave parameter includes: Determine a voltage waveform periodic characteristic for the electrolytic capacitor based on the voltage wave parameter, and determine an initial voltage wave equation, an input power equation, and a discharge current equation of the electrolytic capacitor based on the voltage waveform periodic characteristic; A voltage wave model for the electrolytic capacitor is determined according to an input power equation, a discharge current equation and the initial voltage wave equation of the electrolytic capacitor.

3. The method according to claim 2, characterized in that The step of determining a voltage wave model for the electrolytic capacitor according to an input power equation, a discharge current equation and an initial voltage wave equation of the electrolytic capacitor comprises: Perform mathematical operations on the input power equation and the discharge current equation of the electrolytic capacitor to obtain a first voltage sub-model corresponding to the electrolytic capacitor in the discharge state; Using the initial voltage wave equation as a second voltage sub-model corresponding to the electrolytic capacitor in a charging state; Using the first voltage sub-model and the second voltage sub-model as voltage wave models for the electrolytic capacitor; Wherein, the first voltage sub-model is: Among them, the V b (t) is the voltage parameter of the electrolytic capacitor, V ac is the AC voltage value of the AC input source; P in is the input power of the electrolytic capacitor, C b is the electrolytic capacity parameter of the electrolytic capacitor, t is the time parameter, and t1 is the time point when the electrolytic capacitor is converted from the discharge state to the charge state; The second voltage sub-model is: Among them, F ac is the AC operating frequency of the AC input source, T is the charge and discharge cycle of the electrolytic capacitor, T= .

4. The method according to claim 1, characterized in that: The initial input current function for the switching power supply circuit is constructed based on the electrical parameter characteristics corresponding to the voltage wave model, and the electrical parameter average value and electrolytic output power equation for the electrolytic capacitor are determined based on the voltage wave model and the initial input current function, including: Based on the voltage wave model, the charge and discharge characteristics and the voltage waveform period characteristics of the electrolytic capacitor are acquired, and based on the charge and discharge characteristics and the voltage waveform period characteristics, a triangular fitting process is performed on the input current waveform to obtain an initial input current function for the switching power supply circuit; An average value of electrical parameters for the electrolytic capacitor is determined based on the voltage wave model, and an electrolytic output power equation is constructed based on the average value of the electrical parameters and an average current parameter of the electrolytic capacitor.

5. The method according to claim 4, characterized in that The step of performing triangular fitting processing on the input current waveform based on the charge-discharge characteristic and the voltage waveform period characteristic to obtain an initial input current function for the switching power supply circuit includes: Determine the input current cycle characteristics for the switching power supply circuit based on the charging and discharging characteristics, and perform triangular sine fitting processing on the input current waveform based on the voltage waveform cycle characteristics and the input current cycle characteristics to obtain an initial input current function for the switching power supply circuit; Wherein, the initial input current function includes: Among them, I inac(t) is the input current parameter of the switching power supply circuit, t is the time parameter, is the charge and discharge cycle T of the electrolytic capacitor, F ac is the AC operating frequency of the AC input source, t1 is the time point when the electrolytic capacitor is converted from the discharge state to the charge state, I acmax is the maximum value of the input current parameter.

6. The method according to claim 5, characterized in that The determining of the circuit current parameters for the switching power supply circuit based on the initial input current function, the average value of the electrical parameters and the electrolytic output power equation comprises: Based on the initial input current function, the average value of the electrical parameters and the electrolysis output power equation, determining the maximum input current of the switching power supply circuit, the input current function corresponding to the initial input current function and the input current effective value; Among them, the average value of the electrical parameters is: , wherein the V b (t) is the voltage parameter of the electrolytic capacitor, is the average value of the electrical parameter; Wherein, the electrolysis output power equation is: , wherein the P in output power for the electrolysis; Wherein, the effective value of the input current is: , is the effective value of the input current.

7. The method according to claim 1, characterized in that The determining of the device loss parameter for the switching power supply circuit based on the circuit current parameter includes: Determine a first loss parameter for the switching power supply circuit based on the circuit current parameter, wherein the first loss parameter is a loss value of the thermistor in the switching power supply circuit; and / or, determining a second loss parameter for the switching power supply circuit based on the circuit current parameter, wherein the second loss parameter is a loss value of the common-mode inductor in the switching power supply circuit; and / or, A third loss parameter for the switching power supply circuit is determined based on the circuit current parameter, wherein the third loss parameter is a loss value of the rectifier bridge in the switching power supply circuit.

8. The method according to claim 7, characterized in that The determining a first loss parameter for the switching power supply circuit based on the circuit current parameter comprises: Determine a temperature resistance model for the thermistor by using a temperature resistance curve fitting strategy; Determine an actual resistance value of the thermistor at an actual circuit operating temperature based on the temperature resistance model; A first loss parameter for the switching power supply circuit is determined based on the actual resistance value and the circuit current parameter.

9. The method according to claim 8, characterized in that The method of using a temperature-resistance curve fitting strategy to determine a temperature-resistance model for the thermistor includes: Obtaining a temperature-resistance variation curve for the thermistor, and determining a temperature-resistance model for the thermistor using a preset curve fitting formula and based on a preset number of temperature-resistance sampling pairs indicated in the temperature-resistance variation curve; The preset curve fitting formula is: , in , , the R ntc is the resistance value of the thermistor at the actual working temperature, temp is the actual working temperature of the thermistor, A, B, and C are three constant coefficients, and the three constant coefficients "A, B, and C" are determined based on the temperature-resistance sampling pairs indicated by the preset number.

10. The method according to claim 7, characterized in that The determining of a second loss parameter for the switching power supply circuit based on the circuit current parameter comprises: Acquire the DC resistance value and the actual operating temperature of the common mode inductor, and determine the temperature resistance equivalent coefficient based on the actual operating temperature; A DC resistance value for the common mode inductor is determined based on the DC resistance value and the temperature resistance coefficient, and a second loss parameter for the switching power supply circuit is determined based on the DC resistance and the circuit current parameter.

11. The method according to claim 7, characterized in that The determining of a third loss parameter for the switching power supply circuit based on the circuit current parameter comprises: Equivalent the power loss corresponding to the rectifier bridge to the power loss of a specified number of diodes, and determining a conduction mapping relationship between the conduction voltage, actual operating temperature and the circuit current parameter of the diode; A loss model for the diode is obtained, and a third loss parameter for the rectifier bridge is determined based on the loss model and the conduction mapping relationship.

12. The method according to claim 11, characterized in that The determining a third loss parameter for the rectifier bridge based on the loss model and the conduction mapping relationship includes: Determine a mean on-voltage value for at least one of the actual operating temperatures based on the on-map relationship, and determine a on-temperature coefficient function based on each of the actual operating temperatures and the mean on-voltage value; Determine a third loss parameter for the rectifier bridge based on the conduction temperature coefficient function, the loss model, and the specified quantity; wherein, The on-state temperature coefficient function is: , the temp is the actual working temperature, is the conduction temperature coefficient, a, b, c are preset constants; The loss model is: , the P bri is the power loss of the diode, the F ac is the AC operating frequency of the AC input source, the V bri (t) is the conduction voltage of the diode, and the I inac(t) is the input current parameter of the switching power supply circuit.

13. A computer storage medium, characterized in that: The computer storage medium stores a plurality of instructions, and the instructions are suitable for being loaded by a processor and executing the method steps as claimed in any one of claims 1 to 12.

14. An electronic device, characterized in that: include: A processor and a memory; wherein the memory stores a computer program, and the computer program is suitable for being loaded by the processor and executing the method steps as claimed in any one of claims 1 to 12.

Images