Power semiconductor junction temperature detection method, control method and device

Abstract

The invention discloses a power semiconductor junction temperature detection method, a power semiconductor junction temperature control method and a power semiconductor junction temperature control device, and belongs to the technical field of power electronics. The method comprises the following steps: acquiring a first average current, a first turn-off voltage, a reference point temperature and a reference point thermal impedance of a power semiconductor in a target switching period; determining a first conduction voltage of the power semiconductor based on the first average current, and determining a first conduction loss of the power semiconductor based on the first average current and the first conduction voltage; determining a first turn-on current and a first turn-off current of the power semiconductor based on the first average current and the first turn-off voltage, and determining a second switching loss of the power semiconductor based on the first turn-on current and the first turn-off current; and determining the junction temperature of the power semiconductor based on the first conduction loss, the second switching loss, the reference point temperature and the reference point thermal impedance. The method can improve the accuracy of the junction temperature detection result of the power semiconductor.

Description

Technical Field

[0001] The present application belongs to the field of power electronics technology, and in particular, relates to a power semiconductor junction temperature detection method, control method and device. Background Art

[0002] Power semiconductor devices are the most commonly used devices with the highest failure rate in power electronic systems. The impact of power semiconductor devices on the normal operation of power electronic systems is self-evident. The failure of power semiconductor devices is usually caused by excessive temperature, and the failure rate of the device can double for every 10°C increase in temperature. During use, when the junction temperature of the power semiconductor device exceeds the maximum allowable junction temperature, the power semiconductor chip may experience reliability degradation, output performance attenuation, and may even break down and burn out.

[0003] Therefore, only by accurately measuring the chip junction temperature of power semiconductor devices can thermal management of power semiconductor devices be performed. Summary of the invention

[0004] The present application aims to solve at least one of the technical problems existing in the prior art. To this end, the present application proposes a power semiconductor junction temperature detection method, control method and device, which can improve the accuracy of the junction temperature detection result of the power semiconductor and improve the reliability of the power semiconductor.

[0005] In a first aspect, the present application provides a method for detecting junction temperature of a power semiconductor, the method comprising:

[0006] In a target switching cycle, obtaining a first average current, a first turn-off voltage, a reference point temperature, and a reference point thermal impedance of a power semiconductor;

[0007] Determine a first on-state voltage of the power semiconductor based on the first average current, and determine a first conduction loss of the power semiconductor based on the first average current and the first on-state voltage;

[0008] Determine a first on-current and a first off-current of the power semiconductor based on the first average current and the first off-voltage, and determine a second switching loss of the power semiconductor based on the first on-current and the first off-current;

[0009] A junction temperature of the power semiconductor is determined based on the first conduction loss, the second switching loss, the reference point temperature, and the reference point thermal impedance.

[0010] According to the power semiconductor junction temperature detection method of the present application, the first average current and the first turn-off voltage of the power semiconductor are obtained in real time within the target switching cycle of the power semiconductor, the first conduction loss and the second switching loss of the power semiconductor are calculated according to the first average current and the first turn-off voltage, and the junction temperature is calculated in combination with the reference point temperature and the reference point thermal impedance. The obtained first conduction loss and second switching loss can reflect the real-time energy loss of the power semiconductor. The loss calculation has high accuracy, which can improve the accuracy of the junction temperature detection result of the power semiconductor.

[0011] According to an embodiment of the present application, determining a first on-state voltage of the power semiconductor based on the first average current includes:

[0012] Based on the first average current, the first turn-on voltage is determined through a voltage-current mapping relationship at a first target junction temperature.

[0013] According to an embodiment of the present application, the voltage-current mapping relationship is characterized as a voltage fitting formula, the variable of the voltage fitting formula is the average current of the power semiconductor, and the first on-state voltage is determined based on the first average current through the voltage-current mapping relationship at the first target junction temperature, including:

[0014] Determining the first target junction temperature based on the junction temperature information of the power semiconductor corresponding to the last target switching cycle;

[0015] Determine coefficients corresponding to variables in the voltage fitting formula at the first target junction temperature;

[0016] The first average current is substituted into the voltage fitting formula determined by the coefficient to obtain the first on-state voltage.

[0017] According to an embodiment of the present application, determining the first conduction loss of the power semiconductor based on the first average current and the first conduction voltage includes:

[0018] The product of the first average current, the first on-voltage and the on-time of the power semiconductor in the target switching cycle is taken as the first conduction loss.

[0019] According to an embodiment of the present application, determining a first on-current and a first off-current of the power semiconductor based on the first average current and the first off-voltage includes:

[0020] Determining a first current based on the first turn-off voltage, the on-time of the power semiconductor in the target switching cycle, and an inductance parameter of a peripheral inductor of the power semiconductor;

[0021] taking the difference between the first average current and the first current as the first on-current;

[0022] The sum of the first average current and the first current is used as the first turn-off current.

[0023] According to an embodiment of the present application, determining the second switching loss of the power semiconductor based on the first on-current and the first off-current includes:

[0024] Based on the first conduction current, determining a second conduction loss of the power semiconductor through a conduction loss current mapping relationship;

[0025] Based on the first turn-off current, determining a second turn-off loss of the power semiconductor through a turn-off loss current mapping relationship;

[0026] The second switching loss is determined based on the second turn-on loss and the second turn-off loss.

[0027] According to an embodiment of the present application, determining the second conduction loss of the power semiconductor based on the first conduction current through a conduction loss current mapping relationship includes:

[0028] Based on the first conduction current, determining a second conduction loss of the power semiconductor through the conduction loss current mapping relationship corresponding to the second target junction temperature and the first turn-off voltage;

[0029] The determining, based on the first turn-off current and through a turn-off loss current mapping relationship, a second turn-off loss of the power semiconductor includes:

[0030] Based on the first turn-off current, a second turn-off loss of the power semiconductor is determined through the turn-off loss current mapping relationship corresponding to the second target junction temperature and the first turn-off voltage.

[0031] According to an embodiment of the present application, the conduction loss current mapping relationship is characterized as a conduction loss fitting formula, the variable of the conduction loss fitting formula is the conduction current of the power semiconductor, and the second conduction loss of the power semiconductor is determined based on the first conduction current through the conduction loss current mapping relationship corresponding to the second target junction temperature and the first turn-off voltage, including:

[0032] Determining the second target junction temperature based on the junction temperature information of the power semiconductor corresponding to the previous target switching cycle;

[0033] Determine coefficients corresponding to variables in the conduction loss fitting formula corresponding to the second target junction temperature and the first turn-off voltage;

[0034] Substituting the first conduction current into the conduction loss fitting formula determined by the coefficient, the second conduction loss is obtained.

[0035] According to an embodiment of the present application, the turn-off loss current mapping relationship is characterized as a turn-off loss fitting formula, the variable of the turn-off loss fitting formula is the turn-off current of the power semiconductor, and the second turn-off loss of the power semiconductor is determined based on the first turn-off current through the turn-off loss current mapping relationship corresponding to the second target junction temperature and the first turn-off voltage, including:

[0036] Determining the second target junction temperature based on the junction temperature information of the power semiconductor corresponding to the previous target switching cycle;

[0037] Determine coefficients corresponding to variables in the turn-off loss fitting formula corresponding to the second target junction temperature and the first turn-off voltage;

[0038] Substituting the first turn-off current into the turn-off loss fitting formula determined by the coefficient, the second turn-off loss is obtained.

[0039] According to an embodiment of the present application, determining the junction temperature of the power semiconductor based on the first conduction loss, the second switching loss, the reference point temperature and the reference point thermal impedance includes:

[0040] Adding the first conduction loss and the second switching loss to obtain a total loss of the power semiconductor;

[0041] Multiplying the overall loss, the reference point thermal impedance and the margin coefficient to obtain a first product value;

[0042] The first product value is added to the reference point temperature to obtain the junction temperature of the power semiconductor.

[0043] According to an embodiment of the present application, determining the junction temperature of the power semiconductor based on the first conduction loss, the second switching loss, the reference point temperature and the reference point thermal impedance includes:

[0044] The junction temperature of the power semiconductor is determined based on a plurality of the first conduction losses, a plurality of the second switching losses, a plurality of the reference point temperatures, and a plurality of the reference point thermal impedances within a plurality of the target switching cycles.

[0045] In a second aspect, the present application provides a power semiconductor control method, comprising:

[0046] Get the junction temperature of the power semiconductor;

[0047] When the junction temperature of the power semiconductor is greater than or equal to the junction temperature threshold of the power semiconductor, and the heat dissipation power corresponding to the power semiconductor is greater than or equal to the heat dissipation power threshold, controlling the on-time of the power semiconductor to be reduced to a target on-time;

[0048] Alternatively, when the difference between the junction temperature threshold and the junction temperature of the power semiconductor is greater than a first difference threshold, controlling the heat dissipation power corresponding to the power semiconductor to be reduced to a target heat dissipation power;

[0049] The junction temperature of the power semiconductor is determined based on the power semiconductor junction temperature detection method described in the first aspect above.

[0050] According to the control method of power semiconductors of the present application, by acquiring the junction temperature of the power semiconductor with high accuracy, when the power semiconductor is about to reach a state where the junction temperature is too high and causes abnormal operation, the conduction time of the power semiconductor is controlled to be reduced to the target conduction time, thereby reducing the junction temperature of the power semiconductor. When the junction temperature of the power semiconductor is relatively low, the heat dissipation power corresponding to the power semiconductor is reduced to the target heat dissipation power, which can ensure the safe operation of the power semiconductor, reduce power waste while performing effective heat dissipation, and improve the reliability of the power semiconductor.

[0051] In a third aspect, the present application provides a power semiconductor junction temperature detection device, the device comprising:

[0052] A first acquisition module, used for acquiring a first average current, a first turn-off voltage, a reference point temperature and a reference point thermal impedance of a power semiconductor within a target switching cycle;

[0053] a first processing module, configured to determine a first on-state voltage of the power semiconductor based on the first average current, and determine a first conduction loss of the power semiconductor based on the first average current and the first on-state voltage;

[0054] a second processing module, configured to determine a first on-current and a first off-current of the power semiconductor based on the first average current and the first off-voltage, and determine a second switching loss of the power semiconductor based on the first on-current and the first off-current;

[0055] The third processing module is used to determine the junction temperature of the power semiconductor based on the first conduction loss, the second switching loss, the reference point temperature and the reference point thermal impedance.

[0056] According to the power semiconductor junction temperature detection device of the present application, the first average current and the first turn-off voltage of the power semiconductor are obtained in real time within the target switching cycle of the power semiconductor, the first conduction loss and the second switching loss of the power semiconductor are calculated according to the first average current and the first turn-off voltage, and the junction temperature is calculated in combination with the reference point temperature and the reference point thermal impedance. The obtained first conduction loss and second switching loss can reflect the real-time energy loss of the power semiconductor. The loss calculation has high accuracy, which can improve the accuracy of the junction temperature detection result of the power semiconductor.

[0057] In a fourth aspect, the present application provides a power semiconductor control device, the device comprising:

[0058] A second acquisition module is used to acquire the junction temperature of the power semiconductor;

[0059] a fourth processing module, configured to control the on-time of the power semiconductor to be reduced to a target on-time when the junction temperature of the power semiconductor is greater than or equal to the junction temperature threshold of the power semiconductor and the heat dissipation power corresponding to the power semiconductor is greater than or equal to the heat dissipation power threshold;

[0060] Alternatively, when the difference between the junction temperature threshold and the junction temperature of the power semiconductor is greater than a first difference threshold, controlling the heat dissipation power corresponding to the power semiconductor to be reduced to a target heat dissipation power;

[0061] The junction temperature of the power semiconductor is determined based on the power semiconductor junction temperature detection method described in the first aspect.

[0062] In a fifth aspect, the present application provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the power semiconductor junction temperature detection method and the power semiconductor control method as described in the first aspect are implemented.

[0063] In a sixth aspect, the present application provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the power semiconductor junction temperature detection method as described in the first aspect above and the power semiconductor control method as described in the second aspect above.

[0064] In a seventh aspect, the present application provides a computer program product, comprising a computer program, which, when executed by a processor, implements the power semiconductor junction temperature detection method as described in the first aspect and the power semiconductor control method as described in the second aspect.

[0065] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0066] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0067] Figure 1 It is a flow chart of a power semiconductor junction temperature detection method provided in an embodiment of the present application;

[0068] Figure 2 This is one of the flow charts of the power semiconductor control method provided in the embodiment of the present application;

[0069] Figure 3 This is the second flow chart of the power semiconductor control method provided in the embodiment of the present application;

[0070] Figure 4 It is a schematic diagram of the process of power semiconductor junction temperature detection and power control provided by an embodiment of the present application;

[0071] Figure 5 is a schematic structural diagram of a power semiconductor junction temperature detection device provided in an embodiment of the present application;

[0072] Figure 6 is a schematic structural diagram of a power semiconductor control device provided in an embodiment of the present application;

[0073] Figure 7 It is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0074] The following will be combined with the drawings in the embodiments of the present application to clearly describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments in the present application belong to the scope of protection of this application.

[0075] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here, and the objects distinguished by "first", "second", etc. are generally of one type, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" in the specification and claims represents at least one of the connected objects, and the character " / " generally indicates that the objects associated with each other are in an "or" relationship.

[0076] In combination with the accompanying drawings, the power semiconductor junction temperature detection method, power semiconductor control method, power semiconductor junction temperature detection device, power semiconductor control device, electronic device and readable storage medium provided in the embodiments of the present application are described in detail through specific embodiments and their application scenarios.

[0077] Among them, the power semiconductor junction temperature detection method and the power semiconductor control method can be applied to a terminal, and can be specifically executed by hardware or software in the terminal.

[0078] The terminal includes but is not limited to a desktop computer, and in the following embodiments, a terminal including a display and a touch-sensitive surface is described. However, it should be understood that the terminal may include one or more other physical user interface devices such as a physical keyboard, a mouse, and a joystick.

[0079] The power semiconductor junction temperature detection method provided in the embodiment of the present application can be executed by an electronic device or a functional module or functional entity in the electronic device that can implement the power semiconductor junction temperature detection method. The electronic devices mentioned in the embodiment of the present application include but are not limited to computers, etc. The power semiconductor junction temperature detection method provided in the embodiment of the present application is described below using the electronic device as an example of the execution subject.

[0080] like Figure 1 As shown, the power semiconductor junction temperature detection method includes: step 110 to step 140.

[0081] Step 110: Acquire a first average current, a first turn-off voltage, a reference point temperature, and a reference point thermal impedance of a power semiconductor within a target switching cycle.

[0082] The switching cycle of the power semiconductor may represent the time interval from one turn-on moment to the next turn-on moment of the power semiconductor, and the target switching cycle is the switching cycle for performing junction temperature detection on the power semiconductor.

[0083] It can be understood that the power semiconductor may include a turn-on phase and a turn-off phase within a target switching cycle. In the turn-on phase, the power semiconductor allows current to pass through, and in the turn-off phase, the power semiconductor blocks current from passing through.

[0084] In this embodiment, the first average current is the average current flowing through the power semiconductor corresponding to the target switching cycle. The first average current can be the average current of the power semiconductor in the entire target switching cycle. The first average current can also be the average current of the power semiconductor in the conduction phase of the target switching cycle.

[0085] In this embodiment, the first turn-off voltage is a voltage corresponding to the moment when the power semiconductor switches from the on state to the off state.

[0086] In this step, a current acquisition device and a voltage acquisition device can be set on the power semiconductor. The current acquisition device acquires the current of the power semiconductor in real time, calculates the average value of the current acquired in real time, and obtains the first average current. The voltage acquisition device acquires the voltage of the power semiconductor, thereby obtaining the first shutdown voltage when the power semiconductor is turned off.

[0087] In this embodiment, the reference point temperature is the temperature of the reference point of the power semiconductor. The reference point of the power semiconductor may be a point on the surface of the power semiconductor. The reference point temperature may be collected by a temperature collection device.

[0088] In this embodiment, the reference point thermal impedance is the thermal impedance between the junction of the power semiconductor and the reference point. The thermal impedance provided by the manufacturer can be obtained by referring to the data manual corresponding to the power semiconductor as the reference point thermal impedance, or the reference point thermal impedance can be obtained through experimental simulation and other methods.

[0089] Step 120 : Determine a first on-state voltage of the power semiconductor based on the first average current, and determine a first conduction loss of the power semiconductor based on the first average current and the first on-state voltage.

[0090] The first on-state voltage is a voltage corresponding to when the power semiconductor is in an on-state during a target switching cycle.

[0091] In this step, the first on-state voltage may be obtained according to the first average current through a mapping relationship between an average current of the power semiconductor under a corresponding operating condition and a voltage of the power semiconductor when the power semiconductor is in an on-state.

[0092] In this embodiment, the first conduction loss is the energy loss corresponding to when the power semiconductor is in the on state during the target switching cycle.

[0093] In this step, the first conduction loss may be obtained by calculating the first average current, the first conduction voltage, and the duration during which the power semiconductor is in the on state within the target switching cycle.

[0094] For example, the first average current, the first on-state voltage, and the duration during which the power semiconductor is in the on-state during the target switching cycle may be multiplied to obtain the first conduction loss.

[0095] Step 130 : determining a first on-current and a first off-current of the power semiconductor based on the first average current and the first off-voltage, and determining a second switching loss of the power semiconductor based on the first on-current and the first off-current.

[0096] The first on-state current is a current corresponding to when the power semiconductor switches from an off-state to an on-state within a target switching cycle.

[0097] The first turn-off current is a current corresponding to when the power semiconductor switches from an on state to an off state within a target switching cycle.

[0098] In this step, a current change can be calculated based on the first turn-off voltage and the length of time that the power semiconductor is in the on state during the target switching cycle, and then the first average current and the obtained current change are calculated accordingly to obtain the first on-current and the first off-current, respectively.

[0099] In this embodiment, the second switching loss is the energy loss corresponding to the process of the power semiconductor being switched on or switched off during the target switching cycle.

[0100] In this embodiment, after obtaining the first on-current and the first off-current, the corresponding loss when the power semiconductor is switched on can be calculated based on the first on-current, and the corresponding loss when the power semiconductor is switched off can be calculated based on the first off-current.

[0101] The second switching loss may be obtained according to the loss corresponding to the turn-on moment of the power semiconductor and the loss corresponding to the turn-off moment of the power semiconductor.

[0102] Step 140 : determining a junction temperature of the power semiconductor based on the first conduction loss, the second switching loss, the reference point temperature, and the reference point thermal impedance.

[0103] The junction temperature of the power semiconductor is the temperature of the pn junction inside the power semiconductor.

[0104] In this step, the junction temperature of the power semiconductor can be obtained according to the first conduction loss, the second switching loss, the reference point temperature and the reference point thermal impedance through a pre-constructed junction temperature calculation model.

[0105] That is, the first conduction loss, the second switching loss, the reference point temperature and the reference point thermal impedance are input into a pre-built junction temperature calculation model to perform calculations to obtain the junction temperature of the power semiconductor.

[0106] In the related art, a table is usually looked up according to the working conditions of the power semiconductor to obtain the chip loss of the power semiconductor, and the junction temperature of the power semiconductor is calculated based on the chip loss obtained from the table lookup. The chip loss obtained from the table lookup has low precision, and the junction temperature result obtained has low accuracy.

[0107] According to the power semiconductor junction temperature detection method provided in the embodiment of the present application, the first average current and the first turn-off voltage of the power semiconductor are obtained in real time within the target switching cycle of the power semiconductor, the first conduction loss and the second switching loss of the power semiconductor are calculated according to the first average current and the first turn-off voltage, and the junction temperature is calculated in combination with the reference point temperature and the reference point thermal impedance. The obtained first conduction loss and second switching loss can reflect the real-time energy loss of the power semiconductor. The loss calculation has high accuracy, which can improve the accuracy of the junction temperature detection result of the power semiconductor.

[0108] In some embodiments, determining a first forward voltage of the power semiconductor based on the first average current includes:

[0109] Based on the first average current, a first turn-on voltage is determined through a voltage-current mapping relationship at a first target junction temperature.

[0110] The first target junction temperature is a set value, and the first target junction temperature may be set according to the obtained junction temperature information, or may be set through experimental simulation.

[0111] In this embodiment, the voltage-current mapping relationship may represent a mapping relationship between an average current of the power semiconductor and a voltage when the power semiconductor is in a conducting state.

[0112] In this embodiment, when the first target junction temperature is different, the corresponding voltage-current mapping relationship may be different.

[0113] In this embodiment, after setting the first target junction temperature, the first average current is substituted into the voltage-current mapping relationship at the first target junction temperature to obtain the first on-voltage.

[0114] In some embodiments, the voltage-current mapping relationship is characterized by a voltage fitting formula, the variable of the voltage fitting formula is the average current of the power semiconductor, and based on the first average current, the first on-state voltage is determined by the voltage-current mapping relationship at the first target junction temperature, including:

[0115] Determining a first target junction temperature based on junction temperature information of the power semiconductor corresponding to a previous target switching cycle;

[0116] Determine coefficients corresponding to variables in a voltage fitting formula at a first target junction temperature;

[0117] The first average current is substituted into the voltage fitting formula determined by the coefficient to obtain the first on-state voltage.

[0118] The junction temperature information of the power semiconductor is used to characterize the junction temperature of the power semiconductor calculated within a target switching cycle.

[0119] In this embodiment, the first target junction temperature may be set according to the junction temperature of the power semiconductor calculated in the last target switching cycle. For example, the junction temperature of the power semiconductor calculated in the last target switching cycle may be set as the first target junction temperature.

[0120] The first target junction temperature of the first target switching cycle may be set to a temperature of a housing of the power semiconductor.

[0121] In this embodiment, the voltage-current mapping relationship is represented by a voltage fitting formula, and the variable of the voltage fitting formula is the average current of the power semiconductor.

[0122] It can be understood that the voltage fitting formula can calculate the voltage of the power semiconductor in the on state at a given average current.

[0123] In this embodiment, the voltage fitting formula may be a polynomial, each term in the voltage fitting formula may be an average current of a power semiconductor of a different power term, and each term in the voltage fitting formula corresponds to a coefficient.

[0124] In this embodiment, under different first target junction temperatures, the coefficients corresponding to the variables in the voltage fitting formula may be different.

[0125] In actual implementation, after determining the first target junction temperature, the average current of the power semiconductor can be changed, and the voltage of the power semiconductor in the on-state corresponding to different average currents can be obtained. Based on multiple groups of average currents and voltages in the on-state, the coefficients corresponding to the variables in the voltage fitting formula under the determined first target junction temperature can be obtained through interpolation method.

[0126] In this embodiment, after determining the coefficients corresponding to the variables in the voltage fitting formula at the first target junction temperature, the relationship between the average current of the power semiconductor and the voltage in the on state reflected by the voltage fitting formula is determined, and the first average current is substituted into the voltage fitting formula determined by the coefficient to obtain the first on-state voltage.

[0127] In some embodiments, determining a first conduction loss of the power semiconductor based on the first average current and the first conduction voltage includes:

[0128] The product of the first average current, the first on-state voltage, and the on-state duration of the power semiconductor within the target switching cycle is taken as the first conduction loss.

[0129] The on-time of the power semiconductor in the target switching cycle is the time duration during which the power semiconductor is in the on state in the target switching cycle.

[0130] In this embodiment, the first average current, the first on-voltage, and the on-time of the power semiconductor in the target switching cycle may be multiplied to obtain the first conduction loss.

[0131] In some embodiments, determining a first on-current and a first off-current of a power semiconductor based on a first average current and a first off-voltage includes:

[0132] Determining a first current based on a first turn-off voltage, a conduction time of the power semiconductor in a target switching cycle, and an inductance parameter of a peripheral inductor of the power semiconductor;

[0133] taking the difference between the first average current and the first current as the first on-current;

[0134] The sum of the first average current and the first current is taken as the first turn-off current.

[0135] The peripheral inductor of the power semiconductor is an inductor connected to the power semiconductor, for example, an inverter inductor, a boost inductor, etc.

[0136] The inductance parameter is a parameter that characterizes the electrical characteristics of the peripheral inductance. For example, the inductance parameter may be an inductance value, a quality factor, a rated current, and the like.

[0137] In actual implementation, the first current may be calculated based on the product of the ratio of the first turn-off voltage to the inductance parameter of the peripheral inductor and the conduction time of the power semiconductor in the target switching cycle.

[0138] For example, the first off voltage is V, and the on time is t on , the inductance parameter of the peripheral inductor of the power semiconductor is L, and the first current is

[0139] In this embodiment, the first average current minus the first current obtains the first on-current, and the first average current plus the first current obtains the first off-current.

[0140] In some embodiments, determining a second switching loss of the power semiconductor based on the first on-current and the first off-current includes:

[0141] Based on the first conduction current, determining a second conduction loss of the power semiconductor through a conduction loss current mapping relationship;

[0142] Based on the first turn-off current, determining a second turn-off loss of the power semiconductor through a turn-off loss current mapping relationship;

[0143] The second switching loss is determined based on the second conduction loss and the second turn-off loss. In this embodiment, the second conduction loss is the loss corresponding to when the power semiconductor is switched to conduction, and the conduction loss current mapping relationship can represent the mapping relationship between the current and the corresponding loss when the power semiconductor is switched to conduction.

[0144] In this embodiment, the second conduction loss can be obtained by substituting the first conduction current into the conduction loss current mapping relationship.

[0145] In this embodiment, the second turn-off loss is the loss corresponding to when the power semiconductor is switched to off state, and the turn-off loss current mapping relationship can represent the mapping relationship between the current and the corresponding loss when the power semiconductor is switched to off state.

[0146] In this embodiment, the second turn-off loss can be obtained by substituting the first turn-off current into the turn-off loss current mapping relationship.

[0147] In actual implementation, the second conduction loss is added to the second turn-off loss to obtain the second switching loss.

[0148] In this embodiment, the second conduction loss may be referred to as a turn-on loss, where the turn-on loss is the loss corresponding to when the power semiconductor is switched to conduction, and the second switching loss is equal to the turn-on loss plus the second turn-off loss.

[0149] In some embodiments, based on the first conduction current, determining the second conduction loss of the power semiconductor through a conduction loss current mapping relationship includes:

[0150] Based on the first conduction current, determining a second conduction loss of the power semiconductor through a conduction loss current mapping relationship corresponding to the second target junction temperature and the first turn-off voltage;

[0151] Based on the first turn-off current, determining a second turn-off loss of the power semiconductor through a turn-off loss current mapping relationship includes:

[0152] Based on the first turn-off current, a second turn-off loss of the power semiconductor is determined through a turn-off loss current mapping relationship corresponding to the second target junction temperature and the first turn-off voltage.

[0153] The second target junction temperature is a set value, and the second target junction temperature may be set according to the obtained junction temperature information, or may be set through experimental simulation.

[0154] In this embodiment, when the second target junction temperature and the first turn-off voltage are different, the corresponding conduction loss current mapping relationship may be different.

[0155] In this embodiment, after setting the second target junction temperature and acquiring the first turn-off voltage, the first conduction current is substituted into the conduction loss current mapping relationship corresponding to the second target junction temperature and the first turn-off voltage to obtain the second conduction loss.

[0156] In this embodiment, when the second target junction temperature and the first turn-off voltage are different, the corresponding turn-off loss current mapping relationship may be different.

[0157] In this embodiment, after setting the second target junction temperature and obtaining the first turn-off voltage, the first turn-off current is substituted into the turn-off loss current mapping relationship corresponding to the second target junction temperature and the first turn-off voltage to obtain the second turn-off loss.

[0158] In some embodiments, the conduction loss current mapping relationship is characterized by a conduction loss fitting formula, the variable of the conduction loss fitting formula is the conduction current of the power semiconductor, and based on the first conduction current, the second conduction loss of the power semiconductor is determined by the conduction loss current mapping relationship corresponding to the second target junction temperature and the first turn-off voltage, including:

[0159] Determining a second target junction temperature based on the junction temperature information of the power semiconductor corresponding to the previous target switching cycle;

[0160] Determine the coefficients corresponding to the variables in the conduction loss fitting formula corresponding to the second target junction temperature and the first turn-off voltage;

[0161] Substituting the first conduction current into the conduction loss fitting formula determined by the coefficient, the second conduction loss is obtained.

[0162] In this embodiment, the second target junction temperature may be set according to the junction temperature of the power semiconductor calculated in the last target switching cycle. For example, the junction temperature of the power semiconductor calculated in the last target switching cycle may be set as the second target junction temperature.

[0163] The second target junction temperature of the first target switching cycle may be set to a temperature of a housing of the power semiconductor.

[0164] In this embodiment, the conduction loss current mapping relationship is represented by a conduction loss fitting formula, and the variable of the conduction loss fitting formula is the conduction current of the power semiconductor, that is, the current corresponding to when the power semiconductor is switched to the on state.

[0165] It can be understood that the conduction loss fitting formula can calculate the corresponding loss under a certain current when the power semiconductor is switched to conduction.

[0166] In this embodiment, the conduction loss fitting formula may be a polynomial, each term in the conduction loss fitting formula may be a current of a different power term when the power semiconductor switches to conduction, and each term in the conduction loss fitting formula corresponds to a coefficient.

[0167] In this embodiment, when the second target junction temperature and the first turn-off voltage are different, the coefficients corresponding to the conduction loss fitting formula may be different.

[0168] In actual implementation, after determining the second target junction temperature and the first turn-off voltage, the current when the power semiconductor switches to conduction can be changed, and the corresponding losses of the power semiconductor at different currents when switching to conduction can be obtained. Based on multiple sets of currents and losses, the coefficients corresponding to the variables in the conduction loss fitting formula under the determined second target junction temperature and the first turn-off voltage are obtained through interpolation method.

[0169] In this embodiment, after determining the coefficients corresponding to the variables in the conduction loss fitting formula at the second target junction temperature and the first turn-off voltage, the conduction loss fitting formula reflects the relationship between the current and loss of the power semiconductor when it switches to conduction, and the first conduction current is substituted into the conduction loss fitting formula determined by the coefficient to obtain the second conduction loss.

[0170] In some embodiments, the turn-off loss current mapping relationship is characterized as a turn-off loss fitting formula, the variable of the turn-off loss fitting formula is the turn-off current of the power semiconductor, and based on the first turn-off current, the second turn-off loss of the power semiconductor is determined by the turn-off loss current mapping relationship corresponding to the second target junction temperature and the first turn-off voltage, including:

[0171] Determining a second target junction temperature based on the junction temperature information of the power semiconductor corresponding to the previous target switching cycle;

[0172] Determine coefficients corresponding to variables in a turn-off loss fitting formula corresponding to the second target junction temperature and the first turn-off voltage;

[0173] Substituting the first turn-off current into the turn-off loss fitting formula determined by the coefficient, the second turn-off loss is obtained.

[0174] In this embodiment, the second target junction temperature may be set according to the junction temperature of the power semiconductor calculated in the last target switching cycle. For example, the junction temperature of the power semiconductor calculated in the last target switching cycle may be set as the second target junction temperature.

[0175] The second target junction temperature of the first target switching cycle may be set to a temperature of a housing of the power semiconductor.

[0176] In this embodiment, the turn-off loss current mapping relationship is represented by a turn-off loss fitting formula, and the variable of the turn-off loss fitting formula is the turn-off current of the power semiconductor, that is, the current corresponding to when the power semiconductor is switched to the turn-off state.

[0177] It can be understood that the turn-off loss fitting formula can calculate the corresponding loss under a certain current when the power semiconductor is switched to turn off.

[0178] In this embodiment, the turn-off loss fitting formula may be a polynomial, each term in the turn-off loss fitting formula may be a current of a different power term when the power semiconductor switches to turn-off, and each term in the turn-off loss fitting formula corresponds to a coefficient.

[0179] In this embodiment, when the second target junction temperature and the first turn-off voltage are different, the coefficients corresponding to the turn-off loss fitting formula may be different.

[0180] In actual implementation, after determining the second target junction temperature and the first turn-off voltage, the current when the power semiconductor switches to shutdown can be changed, and the corresponding losses of the power semiconductor at different currents when switching to shutdown can be obtained. Based on multiple sets of currents and losses, the coefficients corresponding to the variables in the turn-off loss fitting formula under the determined second target junction temperature and the first turn-off voltage are obtained through interpolation method.

[0181] In this embodiment, after determining the coefficients corresponding to the variables in the turn-off loss fitting formula at the second target junction temperature and the first turn-off voltage, the turn-off loss fitting formula reflects the relationship between the current and loss of the power semiconductor when it switches to shutdown. By substituting the first turn-off current into the turn-off loss fitting formula determined by the coefficient, the second turn-off loss can be obtained.

[0182] In some embodiments, determining a junction temperature of a power semiconductor based on a first conduction loss, a second switching loss, a reference point temperature, and a reference point thermal impedance includes:

[0183] Adding the first conduction loss and the second switching loss to obtain the total loss of the power semiconductor;

[0184] Multiply the total loss, the reference point thermal impedance and the margin factor to obtain a first product value;

[0185] The first product value is added to the reference point temperature to obtain the junction temperature of the power semiconductor.

[0186] The total loss of the power semiconductor is the sum of the energy loss of the power semiconductor during the target switching cycle, and the total loss includes the first conduction loss and the second switching loss.

[0187] In this embodiment, the margin factor is a factor of an additional performance space reserved for maintaining stable and reliable operation of the power semiconductor.

[0188] When calculating the junction temperature of the power semiconductor during thermal management closed-loop control, multiplying it by the margin factor can ensure the thermal stability of the power semiconductor throughout its life cycle.

[0189] In this embodiment, the total loss is multiplied by the reference point thermal impedance and then multiplied by the margin coefficient to obtain a first product value, and the first product value is added to the reference point temperature to obtain the junction temperature of the power semiconductor.

[0190] In some embodiments, determining a junction temperature of a power semiconductor based on a first conduction loss, a second switching loss, a reference point temperature, and a reference point thermal impedance includes:

[0191] A junction temperature of the power semiconductor is determined based on a plurality of first conduction losses, a plurality of second switching losses, a plurality of reference point temperatures, and a plurality of reference point thermal impedances within a plurality of target switching cycles.

[0192] In this embodiment, the total loss of the power semiconductor in each target switching cycle can be calculated, and by comparing the total loss of the power semiconductor obtained in each target switching cycle, a suitable total loss is selected, for example, the maximum total loss is selected, and the junction temperature of the power semiconductor is calculated.

[0193] In this embodiment, the total loss of the power semiconductor in each target switching cycle may also be calculated, and the total loss obtained in each target switching cycle may be added together to calculate the junction temperature of the power semiconductor.

[0194] It can be understood that the overall loss includes a first conduction loss and a second switching loss.

[0195] An embodiment of the present application also provides a method for controlling a power semiconductor.

[0196] The control method for power semiconductors provided in the embodiments of the present application may be executed by an electronic device or a functional module or functional entity in the electronic device that can implement the control method for power semiconductors. The electronic devices mentioned in the embodiments of the present application include but are not limited to computers, etc. The control method for power semiconductors provided in the embodiments of the present application is described below using an electronic device as an example of an execution subject.

[0197] like Figure 2 , Figure 3 As shown, the power semiconductor control method includes: step 210, step 220 and step 320.

[0198] Step 210: Obtain the junction temperature of the power semiconductor.

[0199] The junction temperature of the power semiconductor is determined based on the above-mentioned power semiconductor junction temperature detection method.

[0200] Step 220 : When the junction temperature of the power semiconductor is greater than or equal to the junction temperature threshold of the power semiconductor and the heat dissipation power corresponding to the power semiconductor is greater than or equal to the heat dissipation power threshold, control the on-time of the power semiconductor to be reduced to the target on-time.

[0201] Alternatively, in step 320, when the difference between the junction temperature threshold and the junction temperature of the power semiconductor is greater than the first difference threshold, the heat dissipation power corresponding to the power semiconductor is controlled to be reduced to the target heat dissipation power.

[0202] The junction temperature threshold of the power semiconductor is a preset value, and the junction temperature threshold may be determined based on the maximum junction temperature that the power semiconductor can withstand. For example, the junction temperature threshold may be equal to the maximum junction temperature that the power semiconductor can withstand.

[0203] In this embodiment, the heat dissipation power of the power semiconductor is the power corresponding to the heat generated by the power semiconductor during operation.

[0204] The heat dissipation power threshold is a set value, and the heat dissipation power threshold may be determined based on the maximum heat dissipation power that the power semiconductor can withstand. For example, the heat dissipation power threshold may be equal to the maximum heat dissipation power that the power semiconductor can withstand.

[0205] In this embodiment, when the junction temperature of the power semiconductor is greater than or equal to the junction temperature threshold of the power semiconductor, and the heat dissipation power corresponding to the power semiconductor is greater than or equal to the heat dissipation power threshold, it indicates that the power semiconductor is about to reach a state where the junction temperature is too high, resulting in abnormal operation. At this time, the on-time of the power semiconductor can be controlled to be reduced to the target on-time.

[0206] The target on-time may be a set time, and reducing the on-time of the power semiconductor to the target on-time can ensure that the junction temperature of the power semiconductor is reduced.

[0207] In this embodiment, when the difference between the junction temperature threshold and the junction temperature of the power semiconductor is greater than the first difference threshold, the heat dissipation power corresponding to the power semiconductor is controlled to be reduced to the target heat dissipation power.

[0208] The first difference threshold is a set value, and when the difference between the junction temperature threshold and the junction temperature of the power semiconductor is greater than the first difference threshold, it indicates that the junction temperature of the power semiconductor is relatively low.

[0209] When the junction temperature of the power semiconductor is low, the heat dissipation power corresponding to the power semiconductor can be reduced to achieve the target heat dissipation power. When the heat dissipation power corresponding to the power semiconductor is reduced to the target heat dissipation power, effective heat dissipation can be ensured while reducing power waste.

[0210] According to the control method of power semiconductors provided in the embodiments of the present application, by acquiring the junction temperature of the power semiconductor with high accuracy, when the power semiconductor is about to reach a state where the junction temperature is too high and causes abnormal operation, the conduction time of the power semiconductor is controlled to be reduced to a target conduction time, thereby reducing the junction temperature of the power semiconductor. When the junction temperature of the power semiconductor is relatively low, the heat dissipation power corresponding to the power semiconductor is reduced to the target heat dissipation power, which can ensure the safe operation of the power semiconductor, reduce power waste while performing effective heat dissipation, and improve the reliability of the power semiconductor.

[0211] A specific embodiment is described below.

[0212] The power semiconductor is set in the power electronic system. The actual application conditions of the power electronic system are simulated by experiment to obtain the total loss Pti(t on ,I,V,Tref)=first conduction loss+second switching loss, the second switching loss can be a function of the first average current I flowing through the power semiconductor, the first turn-off voltage V of the power semiconductor and the reference point temperature Tref, the first conduction loss can be a function of the first average current I flowing through the power semiconductor, the first turn-off voltage V on , the conduction time t of the power semiconductor on , and the reference point temperature Tref are functionally related.

[0213] A thermal impedance model is established, and the reference point thermal impedance Rjr between the reference point and the junction of the power semiconductor is obtained by actual measurement. The thermal impedance between the reference point and the junction of the power semiconductor is not affected by the environment and is relatively stable.

[0214] like Figure 4 As shown, step 1, according to the software, the conduction time t of the power semiconductor in the current switching frequency cycle, that is, the target switching cycle, is controlled. on The data is collected by collecting the first average current I flowing through the power semiconductor, the first turn-off voltage V of the power semiconductor and the reference point temperature Tref, and the overall loss of the power semiconductor in the target switching cycle can be calculated.

[0215] Step 2: Perform data processing, that is, calculate the total loss of the power semiconductor within a target switching cycle.

[0216] In this embodiment, the first conduction loss = the first average current I×the first conduction voltage V on ×Conduction time t on .

[0217] Among them, the first conduction voltage V on The corresponding voltage fitting formula is a·I 3 +b·I 2 +c·I 1 +d·I0.5 +e, fitting the voltage fitting formula corresponding to different first target junction temperatures. At a given first target junction temperature, the voltage fitting formula is fitted by the linear difference.

[0218] For example, Table 1 shows that when the first target junction temperature is 140° C., the average current is changed to obtain the on-voltage, and interpolation fitting is performed. Table 2 shows the fitting result corresponding to Table 1.

[0219] The voltage fitting formula is: Among them, V on_140℃ It shows the on-state voltage when the first target junction temperature is 140°C.

[0220] Table 1

[0221] temperature 140 Current On-state voltage Formula fitting results 0 0.416 0.40406 1 0.5908 0.604289419 2 0.673 0.683056181 3 0.73252 0.741974919 6 0.87744 0.870675013 9 0.97864 0.966121867 12 1.05484 1.044990982 15 1.12008 1.113715205 18 1.17688 1.175572805 21 1.23228 1.232493819 24 1.28284 1.285720835 27 1.33248 1.336103861 30 1.3808 1.384250126 33 1.4282 1.430607532 36 1.47076 1.475514487 39 1.5124 1.519231332 42 1.5558 1.561961037 45 1.59944 1.60386334 48 1.64576 1.645064694 51 1.693 1.685665455 54 1.73296 1.725745188 57 1.77108 1.76536666 60 1.8102 1.804578904 63 1.84648 1.843419591 66 1.88 1.881916907 70 1.9242 1.932746433

[0222] In this embodiment, to calculate the second switching loss, the first on-current and the first off-current are first obtained, and the first average current I and the on-time t obtained by sampling are calculated. on and the first turn-off voltage V, the first on-current And the first off current Where, L is the inductance parameter of the peripheral inductor of the power semiconductor. When the inductance of the peripheral inductor changes with temperature, the corresponding function can be added to calculate the inductance, I on is the first conduction current, I off is the first off current.

[0223] Table 2

[0224] index Constant term Numeric 3 a -2.6466E-07 2 b 8.2884E-05 1 c -7.4832E-03 0.5 d 2.0763E-01 0 e 4.0406E-01

[0225] When the first turn-off voltage is 400 V, at different second target junction temperatures, the turn-on loss fitting formula and the turn-off loss fitting formula are fitted by linear interpolation.

[0226] The conduction loss fitting formula is: E on_400 It represents the second conduction loss when the first turn-off voltage is 400V.

[0227] The turn-off loss fitting formula is: E off_400 It represents the second turn-off loss when the first turn-off voltage is 400V.

[0228] It should be noted that the corresponding coefficients in the turn-on loss fitting formula and the turn-off loss fitting formula may be the same.

[0229] For example, Table 3 shows that when the second target junction temperature is 140° C. and the first turn-off voltage is 400 V, the first conduction current is changed to obtain the second conduction loss, and interpolation fitting is performed. Table 4 shows the corresponding fitting result.

[0230] The conduction loss fitting formula is:

[0231]

[0232] Step 3: Calculate the total loss of the power semiconductor within multiple target switching cycles, and sum the total loss calculated within each target switching cycle Pt=Pt1+…+Ptn, where Pt is the final total loss of the power semiconductor, Pt1 is the total loss of the power semiconductor within the first target switching cycle, and Ptn is the total loss of the power semiconductor within the nth target switching cycle.

[0233] Step 4: Obtain the reference point temperature and the final determined total loss of the power semiconductor, and estimate the junction temperature of the power semiconductor in real time: Tj=Tref+k×Rjr×Pt, where k is the margin coefficient.

[0234] Step 5: The junction temperature Tj of the power semiconductor is compared with the junction temperature threshold Tjmax, and the heat dissipation power Ph is compared with the heat dissipation power threshold Phmax.

[0235] When the junction temperature Tj of the power semiconductor is greater than the junction temperature threshold Tjmax, and the heat dissipation power Ph is greater than the heat dissipation power threshold Phmax, the output power is reduced, that is, the software reduces the output power of the power electronic system by controlling the conduction time of the power semiconductor, thereby reducing the loss of the power semiconductor.

[0236] The first difference threshold is 10° C. When Tjmax-Tj>10° C., it indicates that the junction temperature margin of the power semiconductor is large, and the heat dissipation power can be reduced to 95% of the current heat dissipation power to achieve thermal balance.

[0237] Table 3

[0238]

[0239] Table 4

[0240] coefficient Numeric Coefficient of the fourth order term -1.44508E-05 Coefficient of third order term 0.001078483 Second-order coefficient 0.18396452 First-order coefficient 2.237686027 0th degree coefficient 44.10834343

[0241] In this embodiment, accurate junction temperature estimation and the heat dissipation power of the power semiconductor form a closed-loop control, which can effectively reduce the risk of thermal failure of the power semiconductor. At the same time, it can reduce unnecessary heat dissipation power, improve the working efficiency of the power electronic system, and improve the environmental compatibility and performance maximization of the power electronic system.

[0242] The power semiconductor junction temperature detection method provided in the embodiment of the present application can be executed by a power semiconductor junction temperature detection device. In the embodiment of the present application, the power semiconductor junction temperature detection method is executed by a power semiconductor junction temperature detection device as an example to illustrate the power semiconductor junction temperature detection device provided in the embodiment of the present application.

[0243] An embodiment of the present application also provides a power semiconductor junction temperature detection device.

[0244] like Figure 5 As shown, the power semiconductor junction temperature detection device includes:

[0245] A first acquisition module 510 is used to acquire a first average current, a first turn-off voltage, a reference point temperature and a reference point thermal impedance of a power semiconductor within a target switching cycle;

[0246] A first processing module 520, configured to determine a first conduction voltage of the power semiconductor based on the first average current, and determine a first conduction loss of the power semiconductor based on the first average current and the first conduction voltage;

[0247] A second processing module 530, configured to determine a first on-current and a first off-current of the power semiconductor based on the first average current and the first off-voltage, and determine a second switching loss of the power semiconductor based on the first on-current and the first off-current;

[0248] The third processing module 540 is used to determine the junction temperature of the power semiconductor based on the first conduction loss, the second switching loss, the reference point temperature and the reference point thermal impedance.

[0249] According to the power semiconductor junction temperature detection device provided in the embodiment of the present application, the first average current and the first turn-off voltage of the power semiconductor are obtained in real time during the target switching cycle of the power semiconductor, the first conduction loss and the second switching loss of the power semiconductor are calculated according to the first average current and the first turn-off voltage, and the junction temperature is calculated in combination with the reference point temperature and the reference point thermal impedance. The obtained first conduction loss and second switching loss can reflect the real-time energy loss of the power semiconductor. The loss calculation has high accuracy, which can improve the accuracy of the junction temperature result of the power semiconductor.

[0250] In some embodiments, the first processing module 520 is used to determine the first turn-on voltage based on the first average current through a voltage-current mapping relationship at a first target junction temperature.

[0251] In some embodiments, the voltage-current mapping relationship is characterized by a voltage fitting formula, the variable of the voltage fitting formula is the average current of the power semiconductor, and the first processing module 520 is used to determine the first target junction temperature based on the junction temperature information of the power semiconductor corresponding to the previous target switching cycle;

[0252] Determine coefficients corresponding to variables in a voltage fitting formula at a first target junction temperature;

[0253] The first average current is substituted into the voltage fitting formula determined by the coefficient to obtain the first on-state voltage.

[0254] In some embodiments, the first processing module 520 is configured to use the product of the first average current, the first conduction voltage, and the conduction time of the power semiconductor in the target switching cycle as the first conduction loss.

[0255] In some embodiments, the second processing module 530 is used to determine the first current based on the first turn-off voltage, the on-time of the power semiconductor in the target switching cycle, and the inductance parameter of the peripheral inductor of the power semiconductor;

[0256] taking the difference between the first average current and the first current as the first on-current;

[0257] The sum of the first average current and the first current is taken as the first turn-off current.

[0258] In some embodiments, the second processing module 530 is used to determine the second conduction loss of the power semiconductor based on the first conduction current through a conduction loss current mapping relationship;

[0259] Based on the first turn-off current, determining a second turn-off loss of the power semiconductor through a turn-off loss current mapping relationship;

[0260] Based on the second turn-on loss and the second turn-off loss, a second switching loss is determined.

[0261] In some embodiments, the second processing module 530 is used to determine the second conduction loss of the power semiconductor based on the first conduction current through a conduction loss current mapping relationship corresponding to the second target junction temperature and the first turn-off voltage;

[0262] Based on the first turn-off current, a second turn-off loss of the power semiconductor is determined through a turn-off loss current mapping relationship corresponding to the second target junction temperature and the first turn-off voltage.

[0263] In some embodiments, the conduction loss current mapping relationship is characterized by a conduction loss fitting formula, the variable of the conduction loss fitting formula is the conduction current of the power semiconductor, and the second processing module 530 is used to determine the second target junction temperature based on the junction temperature information of the power semiconductor corresponding to the previous target switching cycle;

[0264] Determine the coefficients corresponding to the variables in the conduction loss fitting formula corresponding to the second target junction temperature and the first turn-off voltage;

[0265] Substituting the first conduction current into the conduction loss fitting formula determined by the coefficient, the second conduction loss is obtained.

[0266] In some embodiments, the turn-off loss current mapping relationship is characterized by a turn-off loss fitting formula, the variable of the turn-off loss fitting formula is the turn-off current of the power semiconductor, and the second processing module 530 is used to determine the second target junction temperature based on the junction temperature information of the power semiconductor corresponding to the previous target switching cycle;

[0267] Determine coefficients corresponding to variables in a turn-off loss fitting formula corresponding to the second target junction temperature and the first turn-off voltage;

[0268] Substituting the first turn-off current into the turn-off loss fitting formula determined by the coefficient, the second turn-off loss is obtained.

[0269] In some embodiments, the third processing module 540 is used to add the first conduction loss and the second switching loss to obtain the total loss of the power semiconductor;

[0270] Multiply the total loss, the reference point thermal impedance and the margin factor to obtain a first product value;

[0271] The first product value is added to the reference point temperature to obtain the junction temperature of the power semiconductor.

[0272] In some embodiments, the third processing module 540 is configured to determine the junction temperature of the power semiconductor based on a plurality of first conduction losses, a plurality of second switching losses, a plurality of reference point temperatures, and a plurality of reference point thermal impedances within a plurality of target switching cycles.

[0273] The power semiconductor control method provided in the embodiment of the present application can be executed by a power semiconductor control device. In the embodiment of the present application, the power semiconductor control method executed by a power semiconductor control device is taken as an example to illustrate the power semiconductor control device provided in the embodiment of the present application.

[0274] An embodiment of the present application also provides a control device for a power semiconductor.

[0275] like Figure 6 As shown, the control device of the power semiconductor includes:

[0276] A second acquisition module 610, used to acquire the junction temperature of the power semiconductor;

[0277] The fourth processing module 620 is used to control the on-time of the power semiconductor to be reduced to the target on-time when the junction temperature of the power semiconductor is greater than or equal to the junction temperature threshold of the power semiconductor and the heat dissipation power corresponding to the power semiconductor is greater than or equal to the heat dissipation power threshold;

[0278] Alternatively, when the difference between the junction temperature threshold and the junction temperature of the power semiconductor is greater than the first difference threshold, controlling the heat dissipation power corresponding to the power semiconductor to be reduced to the target heat dissipation power;

[0279] The junction temperature of the power semiconductor is determined based on the above-mentioned power semiconductor junction temperature detection method.

[0280] According to the control device for power semiconductors provided in the embodiments of the present application, by acquiring the junction temperature of the power semiconductor with high accuracy, when the power semiconductor is about to reach a state where the junction temperature is too high and causes abnormal operation, the on-time of the power semiconductor is controlled to be reduced to a target on-time, thereby reducing the junction temperature of the power semiconductor. When the junction temperature of the power semiconductor is relatively low, the heat dissipation power corresponding to the power semiconductor is reduced to the target heat dissipation power, thereby ensuring the safe operation of the power semiconductor and reducing power waste while performing effective heat dissipation.

[0281] The power semiconductor junction temperature detection device and the power semiconductor control device in the embodiment of the present application can be an electronic device, or a component in an electronic device, such as an integrated circuit or a chip. The electronic device can be a terminal, or other devices other than a terminal. Exemplarily, the electronic device can be a laptop, a mobile Internet device (Mobile Internet Device, MID), a robot, an ultra-mobile personal computer (ultra-mobile personal computer, UMPC), a netbook, etc., and can also be a server, a network attached storage (Network Attached Storage, NAS), a personal computer (personal computer, PC), etc., which is not specifically limited in the embodiment of the present application.

[0282] The power semiconductor junction temperature detection device and the power semiconductor control device in the embodiment of the present application may be a device having an operating system. The operating system may be an Android operating system, an IOS operating system, or other possible operating systems, which are not specifically limited in the embodiment of the present application.

[0283] The power semiconductor junction temperature detection device provided in the embodiment of the present application can achieve Figure 1 To avoid repetition, the various processes implemented by the method embodiment are not described here.

[0284] The power semiconductor control device provided in the embodiment of the present application can achieve Figure 2 and Figure 3 To avoid repetition, the various processes implemented by the method embodiment are not described here.

[0285] In some embodiments, Figure 7As shown, an embodiment of the present application also provides an electronic device 700, including a processor 701, a memory 702, and a computer program stored in the memory 702 and executable on the processor 701. When the program is executed by the processor 701, each process of the above-mentioned power semiconductor junction temperature detection method and the above-mentioned power semiconductor control method embodiment is implemented, and the same technical effect can be achieved. To avoid repetition, it will not be repeated here.

[0286] It should be noted that the electronic devices in the embodiments of the present application include the mobile electronic devices and non-mobile electronic devices mentioned above.

[0287] An embodiment of the present application also provides a non-transitory computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the various processes of the above-mentioned power semiconductor junction temperature detection method and the above-mentioned power semiconductor control method embodiments are implemented, and the same technical effect can be achieved. To avoid repetition, it will not be repeated here.

[0288] The processor is the processor in the electronic device described in the above embodiment. The readable storage medium includes a computer readable storage medium, such as a computer read-only memory ROM, a random access memory RAM, a magnetic disk or an optical disk.

[0289] An embodiment of the present application also provides a computer program product, including a computer program, which, when executed by a processor, implements the above-mentioned power semiconductor junction temperature detection method and the above-mentioned power semiconductor control method.

[0290] The processor is the processor in the electronic device described in the above embodiment. The readable storage medium includes a computer readable storage medium, such as a computer read-only memory ROM, a random access memory RAM, a magnetic disk or an optical disk.

[0291] An embodiment of the present application further provides a chip, which includes a processor and a communication interface, wherein the communication interface is coupled to the processor, and the processor is used to run programs or instructions to implement the various processes of the above-mentioned power semiconductor junction temperature detection method and the above-mentioned power semiconductor control method embodiments, and can achieve the same technical effect. To avoid repetition, they will not be repeated here.

[0292] It should be understood that the chip mentioned in the embodiments of the present application can also be called a system-level chip, a system chip, a chip system or a system-on-chip chip, etc.

[0293] It should be noted that, in this article, the term "comprises", "includes" or any other variant thereof is intended to cover non-exclusive inclusion, so that the process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "including one..." do not exclude the presence of other identical elements in the process, method, article or device including the element. In addition, it should be pointed out that the scope of the method and device in the embodiment of the present application is not limited to performing functions in the order shown or discussed, and may also include performing functions in a substantially simultaneous manner or in reverse order according to the functions involved, for example, the described method may be performed in an order different from that described, and various steps may also be added, omitted, or combined. In addition, the features described with reference to certain examples may be combined in other examples.

[0294] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present application, or the part that contributes to the prior art, can be embodied in the form of a computer software product, which is stored in a storage medium (such as ROM / RAM, a disk, or an optical disk), and includes a number of instructions for a terminal (which can be a mobile phone, a computer, a server, or a network device, etc.) to execute the methods described in each embodiment of the present application.

[0295] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present application, ordinary technicians in this field can also make many forms without departing from the purpose of the present application and the scope of protection of the claims, all of which are within the protection of the present application.

[0296] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0297] Although the embodiments of the present application have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present application, and that the scope of the present application is defined by the claims and their equivalents.

Claims

1. A method for detecting junction temperature of a power semiconductor, characterized in that: include: In a target switching cycle, obtaining a first average current, a first turn-off voltage, a reference point temperature, and a reference point thermal impedance of a power semiconductor; Determine a first on-state voltage of the power semiconductor based on the first average current, and determine a first conduction loss of the power semiconductor based on the first average current and the first on-state voltage; Determine a first on-current and a first off-current of the power semiconductor based on the first average current and the first off-voltage, and determine a second switching loss of the power semiconductor based on the first on-current and the first off-current; A junction temperature of the power semiconductor is determined based on the first conduction loss, the second switching loss, the reference point temperature, and the reference point thermal impedance.

2. The power semiconductor junction temperature detection method according to claim 1, characterized in that: The step of determining a first on-state voltage of the power semiconductor based on the first average current includes: Based on the first average current, the first turn-on voltage is determined through a voltage-current mapping relationship at a first target junction temperature.

3. The power semiconductor junction temperature detection method according to claim 2, characterized in that: The voltage-current mapping relationship is characterized as a voltage fitting formula, the variable of the voltage fitting formula is the average current of the power semiconductor, and the first on-state voltage is determined based on the first average current through the voltage-current mapping relationship at a first target junction temperature, including: Determining the first target junction temperature based on the junction temperature information of the power semiconductor corresponding to the last target switching cycle; Determine coefficients corresponding to variables in the voltage fitting formula at the first target junction temperature; The first average current is substituted into the voltage fitting formula determined by the coefficient to obtain the first on-state voltage.

4. The power semiconductor junction temperature detection method according to claim 1, characterized in that: The determining, based on the first average current and the first conduction voltage, a first conduction loss of the power semiconductor comprises: The product of the first average current, the first on-voltage and the on-time of the power semiconductor in the target switching cycle is taken as the first conduction loss.

5. The power semiconductor junction temperature detection method according to claim 1, characterized in that: The determining, based on the first average current and the first turn-off voltage, a first on-current and a first turn-off current of the power semiconductor comprises: Determining a first current based on the first turn-off voltage, the on-time of the power semiconductor in the target switching cycle, and an inductance parameter of a peripheral inductor of the power semiconductor; taking the difference between the first average current and the first current as the first on-current; The sum of the first average current and the first current is used as the first turn-off current.

6. The power semiconductor junction temperature detection method according to claim 1, characterized in that: The determining, based on the first on-current and the first off-current, a second switching loss of the power semiconductor includes: Based on the first conduction current, determining a second conduction loss of the power semiconductor through a conduction loss current mapping relationship; Based on the first turn-off current, determining a second turn-off loss of the power semiconductor through a turn-off loss current mapping relationship; The second switching loss is determined based on the second turn-on loss and the second turn-off loss.

7. The power semiconductor junction temperature detection method according to claim 6, characterized in that: The determining, based on the first conduction current and through a conduction loss current mapping relationship, a second conduction loss of the power semiconductor includes: Based on the first conduction current, determining a second conduction loss of the power semiconductor through the conduction loss current mapping relationship corresponding to the second target junction temperature and the first turn-off voltage; The determining, based on the first turn-off current and through a turn-off loss current mapping relationship, a second turn-off loss of the power semiconductor includes: Based on the first turn-off current, a second turn-off loss of the power semiconductor is determined through the turn-off loss current mapping relationship corresponding to the second target junction temperature and the first turn-off voltage.

8. The power semiconductor junction temperature detection method according to claim 7, characterized in that: The conduction loss current mapping relationship is characterized as a conduction loss fitting formula, the variable of the conduction loss fitting formula is the conduction current of the power semiconductor, and the second conduction loss of the power semiconductor is determined based on the first conduction current through the conduction loss current mapping relationship corresponding to the second target junction temperature and the first turn-off voltage, including: Determining the second target junction temperature based on the junction temperature information of the power semiconductor corresponding to the previous target switching cycle; Determine coefficients corresponding to variables in the conduction loss fitting formula corresponding to the second target junction temperature and the first turn-off voltage; Substituting the first conduction current into the conduction loss fitting formula determined by the coefficient, the second conduction loss is obtained.

9. The power semiconductor junction temperature detection method according to claim 7, characterized in that: The turn-off loss current mapping relationship is characterized as a turn-off loss fitting formula, the variable of the turn-off loss fitting formula is the turn-off current of the power semiconductor, and the second turn-off loss of the power semiconductor is determined based on the first turn-off current through the turn-off loss current mapping relationship corresponding to the second target junction temperature and the first turn-off voltage, including: Determining the second target junction temperature based on the junction temperature information of the power semiconductor corresponding to the previous target switching cycle; Determine coefficients corresponding to variables in the turn-off loss fitting formula corresponding to the second target junction temperature and the first turn-off voltage; Substituting the first turn-off current into the turn-off loss fitting formula determined by the coefficient, the second turn-off loss is obtained.

10. The power semiconductor junction temperature detection method according to any one of claims 1 to 9, characterized in that: The determining the junction temperature of the power semiconductor based on the first conduction loss, the second switching loss, the reference point temperature and the reference point thermal impedance comprises: Adding the first conduction loss and the second switching loss to obtain a total loss of the power semiconductor; Multiplying the overall loss, the reference point thermal impedance and the margin coefficient to obtain a first product value; The first product value is added to the reference point temperature to obtain the junction temperature of the power semiconductor.

11. The power semiconductor junction temperature detection method according to any one of claims 1 to 9, characterized in that: The determining the junction temperature of the power semiconductor based on the first conduction loss, the second switching loss, the reference point temperature and the reference point thermal impedance comprises: The junction temperature of the power semiconductor is determined based on a plurality of the first conduction losses, a plurality of the second switching losses, a plurality of the reference point temperatures, and a plurality of the reference point thermal impedances within a plurality of the target switching cycles.

12. A method for controlling a power semiconductor, characterized in that: include: Get the junction temperature of the power semiconductor; When the junction temperature of the power semiconductor is greater than or equal to the junction temperature threshold of the power semiconductor, and the heat dissipation power corresponding to the power semiconductor is greater than or equal to the heat dissipation power threshold, controlling the on-time of the power semiconductor to be reduced to a target on-time; Alternatively, when the difference between the junction temperature threshold and the junction temperature of the power semiconductor is greater than a first difference threshold, controlling the heat dissipation power corresponding to the power semiconductor to be reduced to a target heat dissipation power; Wherein, the junction temperature of the power semiconductor is determined based on any power semiconductor junction temperature detection method according to any one of claims 1-11.

13. A power semiconductor junction temperature detection device, characterized in that: include: A first acquisition module, used for acquiring a first average current, a first turn-off voltage, a reference point temperature and a reference point thermal impedance of a power semiconductor within a target switching cycle; a first processing module, configured to determine a first on-state voltage of the power semiconductor based on the first average current, and determine a first conduction loss of the power semiconductor based on the first average current and the first on-state voltage; a second processing module, configured to determine a first on-current and a first off-current of the power semiconductor based on the first average current and the first off-voltage, and determine a second switching loss of the power semiconductor based on the first on-current and the first off-current; The third processing module is used to determine the junction temperature of the power semiconductor based on the first conduction loss, the second switching loss, the reference point temperature and the reference point thermal impedance.

14. A control device for a power semiconductor, characterized in that: include: A second acquisition module is used to acquire the junction temperature of the power semiconductor; a fourth processing module, configured to control the on-time of the power semiconductor to be reduced to a target on-time when the junction temperature of the power semiconductor is greater than or equal to the junction temperature threshold of the power semiconductor and the heat dissipation power corresponding to the power semiconductor is greater than or equal to the heat dissipation power threshold; Alternatively, when the difference between the junction temperature threshold and the junction temperature of the power semiconductor is greater than a first difference threshold, controlling the heat dissipation power corresponding to the power semiconductor to be reduced to a target heat dissipation power; Wherein, the junction temperature of the power semiconductor is determined based on any power semiconductor junction temperature detection method according to any one of claims 1-11.

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