An online junction temperature extraction method, device, equipment and medium of a power module

Abstract

The application provides a power module online junction temperature extraction method, device, equipment and medium, relates to the chip junction temperature detection field, and includes executing chip static test, obtaining test data, calculating the voltage and current change curve of the chip under different junction temperatures; a reference temperature is preset, a first mapping function is established; the connection of the circuit in which the chip is located is tested, and a second mapping function containing the resistance of the connection relative to the change relationship of the chip junction temperature is obtained; the on-current and on-voltage in the circuit under the working state of the power module are collected; a reference temperature and a reference voltage are preset; a target function is established, the target function obtains the change of the on-voltage of the chip under the on-current relative to the reference voltage according to the first mapping function and the second mapping function, and iteratively calculates the real-time junction temperature with the reference temperature as the benchmark; the real-time junction temperature of the power module is obtained by using the target function, and the problem that the existing chip junction temperature collection operation is complex is solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of chip junction temperature detection, and in particular to a power module online junction temperature extraction method, device, equipment and medium. BACKGROUND

[0002] With the development of power semiconductor devices (hereinafter referred to as power devices) and process progress, the reliability requirements of power modules are also getting higher and higher. Temperature and temperature cycle conditions have a considerable impact on their reliability and performance. Since the chips of the power module are packaged inside the module, it is difficult to directly observe them. The existing power module can use sensors, such as built-in NTC thermistors, to obtain chip junction temperature. The operation is complex, and due to the problem of heat transfer rate, NTC cannot directly and quickly reflect the chip junction temperature. It is usually used for overload and over-temperature protection, and there is a lack of a method for accurately and quickly extracting online junction temperature according to the output characteristics of the power module. SUMMARY

[0003] In order to overcome the above technical defects, the purpose of the present application is to provide a power module online junction temperature extraction method, device, equipment and medium, which solves the problem of complex chip junction temperature collection operation.

[0004] The present application discloses a power module online junction temperature extraction method, comprising:

[0005] Performing chip static testing and obtaining test data, calculating the voltage and current variation curves of the chip at different junction temperatures; presetting a reference temperature, establishing a first mapping function according to the voltage and current variation curves of the chip at different junction temperatures, the first mapping function being used to represent the change relationship of the temperature difference of the chip junction temperature relative to the reference temperature and the voltage difference of the chip junction temperature relative to the reference temperature with the current;

[0006] Testing the connecting piece in the circuit where the chip is located, and obtaining a second mapping function containing the resistance variation relationship of the connecting piece relative to the chip junction temperature;

[0007] Collecting the on-current and on-voltage in the circuit under the working state of the power module;

[0008] Calculating the reference voltage corresponding to the on-current when the chip is at the reference temperature;

[0009] Establishing an objective function, the objective function obtaining the change of the chip on-voltage relative to the reference voltage under the on-current according to the second mapping function, and iteratively calculating the real-time junction temperature based on the reference temperature according to the first mapping function;

[0010] According to the conduction current, the conduction voltage, the first mapping function, the reference temperature, the reference voltage, and the second mapping function, the real-time junction temperature of the power module is calculated by using the target function.

[0011] Preferably, the calculating the real-time junction temperature of the power module by using the target function according to the conduction current, the conduction voltage, the first mapping function, the reference temperature, the reference voltage, and the second mapping function comprises:

[0012] An initial junction temperature is set, and the initial resistance of the connecting member at the initial junction temperature is obtained according to the second mapping function;

[0013] The change of the conduction voltage of the chip under the conduction current relative to the reference voltage is calculated according to the initial resistance;

[0014] The change of the temperature relative to the reference temperature is obtained by using the first mapping function according to the change of the conduction voltage of the chip under the conduction current relative to the reference voltage, and a to-be-determined junction temperature is obtained according to the reference temperature;

[0015] The iteration is performed according to the difference between the to-be-determined junction temperature and the initial junction temperature to obtain the real-time junction temperature of the power module.

[0016] Preferably, the calculating the real-time junction temperature of the power module by using the target function according to the conduction current, the conduction voltage, the first mapping function, the reference temperature, the reference voltage, and the second mapping function comprises:

[0017] An initial junction temperature is set, and the initial resistance of the connecting member at the initial junction temperature is obtained according to the second mapping function;

[0018] The initial voltage of the connecting member is obtained according to the initial resistance and the conduction current;

[0019] The difference between the conduction voltage and the initial voltage of the connecting member and the reference voltage is calculated to obtain the change of the conduction voltage of the chip under the conduction current relative to the reference voltage;

[0020] The ratio corresponding to the conduction current is obtained in the first mapping function according to the conduction current, and is multiplied by the change of the conduction voltage of the chip relative to the reference voltage to obtain the change of the temperature relative to the reference temperature;

[0021] The to-be-determined junction temperature is generated by adding the change of the temperature relative to the reference temperature and the reference temperature;

[0022] It is judged whether the difference between the to-be-determined junction temperature and the initial junction temperature is within a preset range;

[0023] If yes, the real-time junction temperature of the power module is obtained according to the to-be-determined junction temperature;

[0024] If not, the initial junction temperature is updated, iterated until the real-time junction temperature of the power module is obtained.

[0025] Preferably, the preset range is 0-1.

[0026] Preferably, the objective function is expressed as:

[0027] T j = K(I) * (V chip -V ref ) + T ref ;

[0028] Wherein, V chip = V-R bonding * I; R bonding = aT j +b is the second mapping function; R bonding is the resistance of the connecting piece; a, b are parameters; T j is the real-time junction temperature; K(I) is the first mapping function; K is the ratio of the temperature difference of the chip junction temperature relative to the reference temperature to the chip voltage difference relative to the chip voltage at the reference temperature in the first mapping function; I is the on-current; V is the on-voltage; V ref is the reference voltage; T ref is the reference temperature.

[0029] Preferably, the connecting piece in the circuit where the chip is located is tested, and the second mapping function containing the resistance of the connecting piece relative to the chip junction temperature is obtained, comprising:

[0030] Detecting the voltage and current across the connecting piece in the circuit where the chip is located to obtain the voltage and current change data set of the connecting piece at different chip junction temperatures;

[0031] Establishing a linear function, and generating the second mapping function by using the linear function according to the voltage and current change data set of the connecting piece at different chip junction temperatures.

[0032] The application also provides a power module online junction temperature extraction module, comprising:

[0033] A first test module is used for performing chip static testing, obtaining test data, calculating the voltage and current change curves of the chip at different junction temperatures, presetting a reference temperature, establishing a first mapping function according to the voltage and current change curves of the chip at different junction temperatures, and the first mapping function is used for representing the change relationship of the ratio of the temperature difference of the chip junction temperature relative to the reference temperature to the chip voltage difference relative to the chip voltage at the reference temperature with the current;

[0034] A second test module is used for testing the connecting piece in the circuit where the chip is located, and obtaining a second mapping function containing the resistance of the connecting piece relative to the chip junction temperature.

[0035] The acquisition module is configured to acquire the conduction current and the conduction voltage in the circuit under the working state of the power module.

[0036] The pre-processing module is configured to calculate a reference voltage corresponding to the conduction current when the chip is at a reference temperature.

[0037] The calculation module is configured to establish a target function, the target function is used to obtain the change of the conduction voltage of the chip under the conduction current relative to the reference voltage according to the second mapping function, and is used to iteratively calculate the real junction temperature based on the reference temperature according to the first mapping function; the real junction temperature of the power module is obtained by using the target function according to the conduction current, the conduction voltage, the first mapping function, the reference temperature, the reference voltage, and the second mapping function.

[0038] Preferably, the calculation module performs the following steps:

[0039] An initial junction temperature is set, and the connection resistance under the initial junction temperature is obtained according to the second mapping function.

[0040] The change of the conduction voltage of the chip under the conduction current relative to the reference voltage is calculated according to the connection resistance.

[0041] The temperature change relative to the reference temperature is obtained by using the first mapping function according to the change of the conduction voltage of the chip under the conduction current relative to the reference voltage, and a to-be-determined junction temperature is obtained according to the reference temperature.

[0042] The iteration is performed according to the difference between the to-be-determined junction temperature and the initial junction temperature to obtain the real junction temperature of the power module.

[0043] The application further provides a computer device, which comprises:

[0044] a memory configured to store executable program codes; and

[0045] a processor configured to call the executable program codes in the memory and perform the steps of the online junction temperature extraction method.

[0046] The application further provides a computer readable storage medium, which stores a computer program.

[0047] The computer program is executed by the processor to implement the steps of the online junction temperature extraction method.

[0048] Compared with the prior art, the above technical scheme has the following beneficial effects:

[0049] In the embodiment, the static test of the chip and the connecting piece is performed in advance, the chip junction temperature and the voltage ratio change with the current, and the connecting piece resistance changes with the temperature, the on current and the on voltage in the acquisition circuit are collected, the on voltage of the chip is calculated and obtained, and is compared with the preset reference voltage, according to the change values of the two, the change of the real-time junction temperature of the chip relative to the reference temperature is calculated and iterated, so as to obtain the real-time junction temperature, thereby realizing the online extraction of the junction temperature of the power module chip, and only the current and the voltage output by the circuit need to be collected in the process, and the operation is convenient. BRIEF DESCRIPTION OF DRAWINGS

[0050] Figure 1 The flow chart of the power module online junction temperature extraction method embodiment one of the application;

[0051] Figure 2 The voltage and current change curve diagram of the chip at multiple different junction temperatures (20℃, 40℃, 60℃, 80℃) in the power module online junction temperature extraction method embodiment one of the application;

[0052] Figure 3 The ratio of the temperature difference of the chip junction temperature relative to the reference temperature and the voltage difference of the chip at the chip junction temperature relative to the reference temperature changes with the current in the power module online junction temperature extraction method embodiment one of the application;

[0053] Figure 4 The test equipment reference diagram of the connecting piece in the circuit where the chip is located in the power module online junction temperature extraction method embodiment one of the application;

[0054] Figure 5 The resistance change curve of the connecting piece relative to the chip junction temperature in the power module online junction temperature extraction method embodiment one of the application;

[0055] Figure 6 The flow chart of obtaining the real-time junction temperature of the power module in the power module online junction temperature extraction method embodiment one of the application;

[0056] Figure 7 The module schematic diagram of the power module online junction temperature extraction device embodiment two of the application;

[0057] Figure 8 The module schematic diagram of the device of the application.

[0058] REFERENCE SIGNS:

[0059] 7 - power module online junction temperature extraction module; 71 - first test module; 72 - second test module; 73 - acquisition module; 74 - preprocessing module; 75 - calculation module. DETAILED DESCRIPTION

[0060] The advantages of the present application are further set forth in the description that follows, and will be appreciated by persons skilled in the art upon reading and understanding the attached figures and detailed description.

[0061] Exemplary embodiments are described herein with reference to the accompanying drawings, of which examples are shown. The following description, in conjunction with the drawings, relates to the preferred embodiments. Unless otherwise noted, like numerals in different drawings denote like or similar elements. The embodiments described in the following examples do not represent all of the embodiments consistent with the present disclosure. Instead, they are merely examples of apparatuses and methods consistent with some aspects of the present disclosure as detailed in the appended claims.

[0062] The terminology used in the description of the present disclosure is for the purpose of describing particular embodiments only and is not intended to be limiting of the present disclosure. As used in the description of the present disclosure and the appended claims, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It also will be understood that the term "and / or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items.

[0063] It will be understood that, although the terms first, second, third, etc. can be used herein to describe various information, these terms are not intended to denote a particular order or hierarchy among the information. Rather, these terms are used merely to distinguish one from another. For example, a first information can be termed a second information, and, similarly, a second information can be termed a first information, without departing from the scope of the present disclosure. As used herein, the word "if' can be construed to mean "when" or "upon" or "in response to determining" depending on the context.

[0064] In the description of the present disclosure, it should be understood that the terms "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate directions or positions based on the directions or positions shown in the drawings, and are used for convenience of description and simplification of description only, and thus cannot be construed to indicate or imply that a device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present disclosure.

[0065] In the description of the present disclosure, unless otherwise specified and limited, it should be noted that the terms "mounting", "connection", "connecting" should be understood in a broad sense, for example, can be mechanical or electrical connection, or internal communication between two elements, or direct connection, or indirect connection through an intermediate medium, and the specific meaning of the above terms can be understood by those skilled in the art according to the specific circumstances.

[0066] In the following description, the suffixes such as "module", "part", or "unit" used for an element are merely for facilitating the description of the present application, and do not have their own particular meanings. Thus, "module" and "part" can be used in mixture.

[0067] Embodiment: The present application provides a power module online junction temperature extraction method. The junction temperature is the actual working temperature of a semiconductor (chip) in an electronic device. Therefore, the chip temperature and the chip junction temperature both represent the obtained temperature on the chip. According to the temperature coefficient of the output characteristic curve of the power module under different currents, the TSEP relationship can be established through a certain mathematical relationship, and the chip junction temperature is extracted online through the output characteristic, without measuring the built-in NTC thermistor as in the prior art. Specifically, refer to Figure 1 , which includes the following steps:

[0068] S100: Perform a chip static test and obtain test data, calculate the voltage and current variation curves of the chip under different junction temperatures; preset a reference temperature, and establish a first mapping function according to the (on) voltage and (on) current variation curves of the chip under different junction temperatures, the first mapping function is used to represent the change relationship of the temperature difference of the chip junction temperature relative to the reference temperature and the chip (on) voltage difference relative to the chip (on) voltage under the reference temperature with the (on) current;

[0069] Specifically, in the above step, the chip static test is performed, and the chip is under a plurality of different junction temperatures, such as 20℃, 40℃, 60℃, and 80℃. The voltage and current variation curves are drawn (refer to Figure 2 ), and the K(I) function curve is established, where the unit of the K(I) function is ℃ / mV (Y axis), and the variable (X axis) is the on current, that is, the change of the ratio of the temperature difference of the chip junction temperature relative to the reference temperature and the on voltage difference of the chip junction temperature relative to the on voltage under the reference temperature with the on current (such as Figure 3 ), that is, the difference ΔT between the chip junction temperature and the reference temperature, the difference ΔU between the chip on voltage under the chip junction temperature and the chip on voltage under the reference temperature under different on currents I, and the change of ΔT / ΔU with I. As an illustration, the temperature difference formed by the chip junction temperature and the reference temperature, the difference of the on voltage of the chip junction temperature relative to the on voltage under the reference temperature, and the ratio of the above temperature difference and the corresponding voltage difference are unique, such as Figure 3 to form a unique curve.

[0070] S200: Test the connecting member in the circuit where the chip is located, and obtain a second mapping function containing the resistance change relationship of the connecting member relative to the chip junction temperature;

[0071] Specifically, in this embodiment, the chip junction temperature is extracted through the circuit output (refer to Figure 4The circuit includes a chip and connectors located in series around the chip (i.e., the connector portion does not include the chip), including but not limited to wires, bonding wires, etc. Therefore, it can be deduced that the circuit output voltage (i.e., the on-state voltage) should be the sum of the chip output voltage (i.e., the chip on-state voltage) and the connector output voltage (i.e., the connector on-state voltage). Thus, the resistance of the connector relative to the chip junction temperature change is obtained as described above (see...). Figure 5 The resistance can be obtained from the junction temperature to obtain the connector output voltage. The chip's turn-on voltage can be obtained from the turn-on voltage minus the connector's turn-on voltage.

[0072] Specifically, the process involves testing the connectors in the circuit containing the chip to obtain a second mapping function showing the relationship between the resistance of the connectors and the chip junction temperature. (See [reference needed]). Figure 4 , Figure 5 ,include:

[0073] S210: Detect the voltage and current across the connectors in the circuit where the chip is located, and obtain a dataset of voltage and current changes of the connectors at different chip junction temperatures;

[0074] Specifically, in the above steps, it should be noted that the voltage and current at both ends of the connector are detected at different chip junction temperatures. During the detection process, the ammeter and power supply are applied to the connector, not to the circuit where the chip is located.

[0075] S220: Establish a linear function, and generate a second mapping function based on the voltage and current variation dataset of the connectors at different chip junction temperatures using the linear function.

[0076] If it can be predetermined that the change in connector resistance relative to the chip junction temperature is mostly linear, and that the change in connector resistance relative to the chip junction temperature for a given chip is uniquely determined, with other factors being negligible, and given that the change in connector resistance relative to the chip junction temperature is linear, then an equation such as R... bonding =aT+b;R bonding Here, is the resistance of the connector; a and b are parameters; T is the chip junction temperature. a and b can be determined by collecting the data set, which is the second mapping function.

[0077] S300: Collects the on-current and on-voltage of the circuit when the power module is in operation;

[0078] Specifically, the aforementioned on-current and on-voltage are the output current and voltage of the circuit where the chip is located. In this embodiment, the chip junction temperature can be directly calculated based on the current and voltage output by the circuit.

[0079] S400: Calculates the reference voltage corresponding to the conduction current at the reference temperature of the chip;

[0080] Specifically, the S100 can be used to obtain the voltage and current variation curve of the chip at any junction temperature as the reference temperature and its corresponding voltage and current variation curve, and the voltage corresponding to the curve is obtained as the reference voltage according to the on-current, the reference temperature is set as the benchmark, and the variation of the on-voltage relative to the reference voltage is determined based on the benchmark, so as to determine the variation of the real-time junction temperature relative to the reference temperature.

[0081] S500: establishing a target function, which obtains the variation of the on-voltage of the chip at the on-current relative to the reference voltage according to the second mapping function, and iteratively calculates the real-time junction temperature based on the reference temperature according to the first mapping function;

[0082] Specifically, the target function is expressed as:

[0083] T j = K(I) × (V chip -V ref ) + T ref ; (1)

[0084] wherein, V chip = V-R bonding ×I (2); R bonding = aT j +b (3), that is, the second mapping function; R bonding is the resistance of the connecting piece; a and b are parameters; T j is the real-time junction temperature; K(I) is the first mapping function; K is the ratio of the temperature difference of the chip junction temperature relative to the reference temperature to the voltage difference of the chip at the chip junction temperature relative to the reference temperature in the first mapping function; I is the on-current; V is the on-voltage; V ref is the reference voltage; and T ref is the reference temperature.

[0085] Specifically, the K(I) is the first mapping function, that is, the ratio of the temperature difference of the chip junction temperature relative to the reference temperature to the voltage difference of the chip at the chip junction temperature relative to the reference temperature in the first mapping function varies with the current, V chip is the on-voltage of the chip, and the on-voltage of the chip = the output on-voltage - the on-voltage of the connecting piece, as described above. Then, the on-voltage of the chip - the reference voltage is used to obtain the variation of the on-voltage of the chip relative to the reference voltage, that is, (V chip -V ref ), and multiplied by the value in the first mapping function corresponding to the on-current at this time, so as to obtain the variation of the real-time junction temperature of the chip relative to the reference temperature, that is, K(I) × (V chip -V ref), and then the real-time junction temperature can be obtained based on the change of the variation and the change of the reference temperature. It should be noted that after substituting the above formula (2) and (3) into formula (1), two variables T j , including R bonding , and the finally obtained value. For the convenience of calculation, any value can be preset for R bonding , and the finally obtained value is compared and iterated to obtain the finally unique value.

[0086] S600: According to the on-current, on-voltage, first mapping function, reference temperature, reference voltage, second mapping function, the target function is used to calculate the real-time junction temperature of the power module.

[0087] Specifically, the real-time junction temperature of the power module is calculated according to the on-current, on-voltage, first mapping function, reference temperature, reference voltage, and second mapping function. Referring to Figure 6 , including:

[0088] S610: Set an initial junction temperature, and obtain the connection component resistance under the initial junction temperature according to the second mapping function.

[0089] That is, the initial resistance of the connection component can be directly obtained through the pre-generated second mapping function.

[0090] S620: Calculate the change of the chip on-voltage relative to the reference voltage under the on-current according to the connection component resistance.

[0091] Specifically, the initial voltage of the connection component can be obtained according to the initial resistance and the on-current, and the difference between the on-voltage and the initial voltage of the connection component and the reference voltage is the change of the chip on-voltage relative to the reference voltage.

[0092] S630: Obtain the temperature change relative to the reference temperature by using the first mapping function according to the change of the chip on-voltage relative to the reference voltage under the on-current, and obtain a to-be-determined junction temperature according to the reference temperature.

[0093] Specifically, the ratio corresponding to the on-current can be obtained in the first mapping function according to the on-current, and multiplied by the change of the chip on-voltage relative to the reference voltage to obtain the change relative to the reference temperature. The to-be-determined junction temperature is generated by adding the reference temperature and the obtained change relative to the reference temperature.

[0094] S640: Perform iteration according to the difference between the to-be-determined junction temperature and the initial junction temperature to obtain the real-time junction temperature of the power module.

[0095] Specifically, the to-be-determined junction temperature is the real-time junction temperature of the chip calculated according to the connection piece at a predetermined initial junction temperature, but in actual process, the junction temperatures of the connection piece and the chip should be within a certain small error range, or consistent, so in the embodiment, whether iteration and recalculation are needed is judged according to the to-be-determined junction temperature and the initial junction temperature, that is, iteration is performed according to the difference between the to-be-determined junction temperature and the initial junction temperature to obtain the real-time junction temperature of the power module, including the following steps:

[0096] S641: judging whether the difference between the to-be-determined junction temperature and the initial junction temperature is within a preset range;

[0097] Specifically, the preset range is 0-1, that is, if the difference between the to-be-determined junction temperature and the initial junction temperature exceeds 1℃, iteration needs to be performed again, the preset initial junction temperature needs to be modified, recalculation needs to be performed again, and a new to-be-determined junction temperature needs to be obtained.

[0098] S642: if yes, obtaining the real-time junction temperature of the power module according to the to-be-determined junction temperature;

[0099] That is, if the above error is met, it means that the initial junction temperature is basically consistent with the calculated to-be-determined junction temperature, that is, the temperature difference between the chip and the connection piece is basically consistent, so it can be determined that the real-time junction temperature of the chip at this time is obtained.

[0100] S643: if no, updating the initial junction temperature and iterating until the real-time junction temperature of the power module is obtained.

[0101] As described above, if the preset range is exceeded, it means that the junction temperature of the chip under the state of the connection piece is greatly different from the calculated junction temperature, which will not occur under the actual same output current (on-current) and output voltage (on-voltage), which means that the preset initial junction temperature is unreasonable, so the initial junction temperature needs to be adjusted. As a supplement, the initial junction temperature can be adjusted according to the positive and negative and size of the difference between the to-be-determined junction temperature and the initial junction temperature. It should be noted that the initial junction temperature can also be set to be consistent with the reference temperature, but there may be a case that the calculated to-be-determined junction temperature is greatly different from the initial junction temperature, and iteration needs to be performed multiple times.

[0102] In the embodiment, the static test of the chip and the connecting piece is performed in advance to obtain a curve of the chip temperature and voltage ratio with the current variation and a curve of the connecting piece resistance with the temperature variation, and then the on-current and on-voltage in the circuit are collected according to the output characteristics, and the calculation is performed by using the target function. Specifically, an initial junction temperature is preset, and the on-voltage of the connecting piece at this time is obtained. The on-voltage of the chip is obtained by the difference between the collected on-voltage and the calculated on-voltage of the connecting piece, and is compared with the preset reference voltage. The change value of the two is calculated, and the change of the real-time junction temperature of the chip calculated according to the change value, the product of the corresponding temperature difference and voltage difference under the on-current, and the change of the reference temperature is calculated. Finally, the real-time junction temperature is obtained by adding the reference temperature. Finally, according to the fact that the junction temperatures of the chip and the connecting piece should be relatively small, the difference between the calculated real-time junction temperature and the initial junction temperature is used to judge whether the iteration update is needed, so as to realize the online extraction of the junction temperature of the power module chip. In this process, only the current and voltage output by the circuit need to be collected, which is convenient to operate, and the accuracy is high according to the output characteristics and the iteration calculation.

[0103] Embodiment two: the embodiment also provides a power module online junction temperature extraction module 7, referring to Figure 7 , the online junction temperature extraction method described in embodiment one is executed, including:

[0104] The first test module 71 is used to perform the chip static test, obtain the test data, calculate the voltage and current variation curves of the chip under different junction temperatures, preset a reference temperature, and establish a first mapping function according to the voltage and current variation curves of the chip under different junction temperatures. The first mapping function is used to represent the change relationship of the chip junction temperature relative to the reference temperature and the ratio of the chip voltage difference relative to the reference temperature with the current.

[0105] Specifically, the voltage and current variation curves of the chip under multiple different junction temperatures, such as 20℃, 40℃, 60℃ and 80℃, are calculated to establish a K(I) function curve, wherein the unit of the K(I) function is ℃ / mV (Y axis), and the variable (X axis) is the current.

[0106] The second test module 72 is used to test the connecting piece in the circuit where the chip is located to obtain a second mapping function containing the resistance variation relationship of the connecting piece relative to the chip junction temperature.

[0107] Specifically, the circuit contains the chip and the connecting piece connected in series around the chip, and the connecting piece includes but is not limited to wires, binding wires and the like.

[0108] The collection module 73 is used to collect the on-current and on-voltage in the circuit under the working state of the power module.

[0109] The on-state current and the on-state voltage are the on-state voltage and the on-state current output by the circuit.

[0110] The pre-processing module 74 is configured to calculate a reference voltage corresponding to the on-state current when the chip is at a reference temperature.

[0111] Specifically, the reference temperature can be directly obtained from the voltage and current variation curve of the chip at different junction temperatures, for example, the voltage and current variation curve at 20 DEG C, the reference temperature is 20 DEG C, and the voltage corresponding to the on-state current can be obtained as the reference voltage according to the curve.

[0112] The calculation module 75 is configured to establish a target function, the target function is used to obtain the variation of the on-state voltage of the chip at the on-state current relative to the reference voltage according to the second mapping function, and the real-time junction temperature is iteratively calculated based on the reference temperature according to the first mapping function; the real-time junction temperature of the power module is calculated by using the target function according to the on-state current, the on-state voltage, the first mapping function, the reference temperature, the reference voltage, the second mapping function.

[0113] The target function is formula (1), (2) and (3) of the first embodiment.

[0114] Specifically, the calculation module performs the following steps:

[0115] An initial junction temperature is set, the connection resistance at the initial junction temperature is obtained according to the second mapping function; the variation of the on-state voltage of the chip at the on-state current relative to the reference voltage is calculated according to the connection resistance; the temperature variation relative to the reference temperature is obtained by using the first mapping function according to the variation of the on-state voltage of the chip at the on-state current relative to the reference voltage, and a to-be-determined junction temperature is obtained according to the reference temperature; the real-time junction temperature of the power module is obtained by performing iteration according to the difference between the to-be-determined junction temperature and the initial junction temperature.

[0116] Embodiment three:

[0117] To achieve the above object, the present application also provides a computer device 8, which can be a smart phone, a tablet computer, a notebook computer, a desktop computer and the like executing a program. The computer device of the present embodiment at least includes but is not limited to: a memory 81 and a processor 82 which can be connected to each other through a device bus. It should be pointed out that, Figure 8 Only the computer device with components is shown, but it should be understood that all the shown components are not required to be implemented, and more or less components can be alternatively implemented.

[0118] In the embodiment, the memory 81 can be an internal storage unit of the computer device, for example, a hard disk or a memory of the computer device. In other embodiments, the memory 81 can also be an external storage device of the computer device, for example, a plug-in hard disk equipped on the computer device, etc. In the embodiment, the memory 81 is generally used to store the operating system and various application software installed on the computer device, for example, the program code of the power module online junction temperature extraction method of the embodiment one, data (such as the first mapping function, the second mapping function, etc.), etc. In addition, the memory 81 can also be used to temporarily store various data (such as the real-time junction temperature, etc.) output or to be output.

[0119] The processor 82 can be a central processing unit (CPU), a controller, a microcontroller, a microprocessor, or other data processing chip in some embodiments. The processor 82 is generally used to control the overall operation of the computer device. In the embodiment, the processor 82 is used to run the program code or process the data stored in the memory 81, for example, to run the power module online junction temperature extraction method of the embodiment one.

[0120] Embodiment four:

[0121] To achieve the above-mentioned purposes, the application further provides a computer readable storage device, which includes a plurality of storage media, such as flash memory, hard disk, random access memory (RAM), static random access memory (SRAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), programmable read-only memory (PROM), magnetic memory, disk, optical disk, server, App application mall, etc., and a computer program is stored on the storage media. The program is executed by the processor 82 to realize the corresponding function. The computer readable storage medium of the embodiment is used to store data, and the processor 82 is executed to realize the power module online junction temperature extraction method of the embodiment one and the power module online junction temperature extraction device of the embodiment two.

[0122] It should be noted that the embodiments of the application have better implementation, and do not limit the application in any form. Any skilled person in the art can change or modify the above-mentioned disclosed technology into equivalent effective embodiments, as long as it does not deviate from the technical solution of the application. Any modification or equivalent change and modification of the above-mentioned embodiments according to the technical essence of the application, all still belong to the scope of the technical solution of the application.

Claims

1. A method for online junction temperature extraction of a power module, characterized in that, The method comprises the following steps: performing chip static test, obtaining test data, calculating the voltage and current variation curves of the chip at different junction temperatures; presetting a reference temperature, establishing a first mapping function according to the voltage and current variation curves of the chip at different junction temperatures, the first mapping function being used to represent the variation relationship of the ratio of the temperature difference of the chip junction temperature relative to the reference temperature to the voltage difference of the chip junction temperature relative to the reference temperature with the current; testing the connecting element in the circuit where the chip is located, and obtaining a second mapping function containing the resistance variation relationship of the connecting element relative to the chip junction temperature; collecting the on-current and on-voltage in the circuit under the real-time working state of the power module, and calculating the reference voltage corresponding to the on-current when the chip is at the reference temperature; A target function is established, which obtains the change of the chip on-voltage relative to the reference voltage under the on-current according to the second mapping function, and iteratively calculates the real-time junction temperature based on the reference temperature according to the first mapping function; the target function is expressed as: Wherein, ; is the second mapping function; is the resistance of the connecting piece; a and b are parameters; is the real-time junction temperature; is the first mapping function; K is the ratio of the temperature difference of the chip junction temperature relative to the reference temperature to the voltage difference of the chip junction temperature relative to the reference temperature in the first mapping function; is the on-current; is the on-voltage; is the reference voltage; is the reference temperature; calculating the real-time junction temperature of the power module by using the target function according to the on-current, on-voltage, first mapping function, reference temperature, reference voltage and second mapping function.

2. The online junction temperature extraction method of claim 1, wherein, The calculation of the real-time junction temperature of the power module by using the target function according to the on-current, on-voltage, first mapping function, reference temperature, reference voltage and second mapping function comprises the following steps: setting an initial junction temperature, and obtaining the resistance of the connecting element at the initial junction temperature according to the second mapping function; calculating the variation of the on-voltage of the chip relative to the reference voltage under the on-current according to the resistance of the connecting element; obtaining the temperature variation relative to the reference temperature by using the first mapping function according to the variation of the on-voltage of the chip relative to the reference voltage under the on-current, and obtaining a to-be-determined junction temperature according to the reference temperature; performing iteration according to the difference between the to-be-determined junction temperature and the initial junction temperature to obtain the real-time junction temperature of the power module.

3. The online junction temperature extraction method of claim 2, wherein, The calculation of the real-time junction temperature of the power module by using the target function according to the on-current, on-voltage, first mapping function, reference temperature, reference voltage and second mapping function comprises the following steps: judging whether the difference between the to-be-determined junction temperature and the initial junction temperature is within a preset range; if yes, obtaining the real-time junction temperature of the power module according to the to-be-determined junction temperature; if no, updating the initial junction temperature and performing iteration until the real-time junction temperature of the power module is obtained.

4. The online junction temperature extraction method according to claim 3, wherein: the preset range is 0-1.

5. The online junction temperature extraction method of claim 1, wherein, The testing of the connecting element in the circuit where the chip is located and the obtaining of the second mapping function containing the resistance variation relationship of the connecting element relative to the chip junction temperature comprise the following steps: detecting the voltage and current at the two ends of the connecting element in the circuit where the chip is located to obtain voltage and current variation data sets of the connecting element at different chip junction temperatures; establishing a linear function, and generating the second mapping function by using the linear function according to the voltage and current variation data sets of the connecting element at different chip junction temperatures.

6. A power module online junction temperature extraction module, comprising: a first test module, configured to perform chip static test, obtain test data, calculate the voltage and current variation curves of the chip at different junction temperatures, preset a reference temperature, and establish a first mapping function according to the voltage and current variation curves of the chip at different junction temperatures, the first mapping function being used to represent the variation relationship of the ratio of the temperature difference of the chip junction temperature relative to the reference temperature to the voltage difference of the chip junction temperature relative to the reference temperature with the current. The second test module is configured to test the connecting element in the circuit where the chip is located, and obtain a second mapping function of a resistance of the connecting element relative to a change of a junction temperature of the chip; The acquisition module is configured to acquire a conduction current and a conduction voltage in the circuit under a working state of the power module; The preprocessing module is configured to calculate a reference voltage corresponding to the conduction current when the chip is at a reference temperature; The computing module is configured to establish a target function, the target function is used to obtain the change of the chip on-voltage relative to the reference voltage under the on-current according to the second mapping function, and the real-time junction temperature is calculated iteratively according to the first mapping function with the reference temperature as the reference; the real-time junction temperature of the power module is obtained by using the target function according to the on-current, the on-voltage, the first mapping function, the reference temperature, the reference voltage and the second mapping function; the target function is expressed as: , wherein, ; is the second mapping function; is the resistance of the connecting piece; a and b are parameters; is the real-time junction temperature; is the first mapping function; K is the ratio of the temperature difference of the chip junction temperature relative to the reference temperature to the voltage difference of the chip junction temperature relative to the chip voltage under the reference temperature in the first mapping function; is the on-current; is the on-voltage; is the reference voltage; is the reference temperature.

7. The online junction temperature extraction module of claim 6, wherein, The computing module performs the following steps: An initial junction temperature is set, and a resistance of the connecting element at the initial junction temperature is obtained according to the second mapping function; A change of a conduction voltage of the chip relative to the reference voltage under the conduction current is calculated according to the resistance of the connecting element; A temperature change relative to the reference temperature is obtained by using the first mapping function according to the change of the conduction voltage of the chip relative to the reference voltage under the conduction current, and a to-be-determined junction temperature is obtained according to the reference temperature; An iteration is performed according to a difference between the to-be-determined junction temperature and the initial junction temperature, so as to obtain a real-time junction temperature of the power module.

8. A computer device, comprising: The computer device comprises: a memory configured to store executable program codes; and a processor configured to call the executable program codes in the memory and perform the steps, including the online junction temperature extraction method according to any one of claims 1 to 5. 9.A computer readable storage medium, on which a computer program is stored, and the computer program is configured to implement the steps of the online junction temperature extraction method according to any one of claims 1 to 5 when executed by a processor. ​

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