A method and device for calculating power device loss

Abstract

The present invention provides a method and apparatus for calculating power device losses. The method comprises: obtaining the system current and ambient temperature of the circuit system in which the power device resides; extracting a first performance curve of the IGBT and a second performance curve of the diode based on the ambient temperature; calculating the IGBT losses based on the system current and the first performance curve to obtain a first loss result; calculating the diode losses based on the system current and the second performance curve to obtain a second loss result; and calculating the total power device losses based on the system current, the first loss result, and the second loss result. While improving the accuracy of calculating power device losses, the method also dynamically calculates the losses, providing strong data support for better evaluating the operating efficiency of the power device.

Description

Technical Field

[0001] The present invention relates to the field of electronic circuits, and in particular to a method and device for calculating power device loss. Background Art

[0002] Power devices play a vital role in daily life, especially in high-power conversion circuits. They perform power conversion, ensuring that the overall high-power conversion circuit meets the demands of production and daily life. Calculating the losses of power devices during operation has long been a difficult problem in the field of electronic circuits. Currently, a rough loss estimate is often made by testing the operating efficiency of power devices. However, this method is inaccurate and cannot dynamically calculate the losses of power devices. Summary of the Invention

[0003] Therefore, the technical problem to be solved by the present invention is to overcome the defects of the prior art in that the power device loss calculation accuracy is low and the loss situation cannot be dynamically calculated, thereby providing a power device loss calculation method and device.

[0004] According to a first aspect, an embodiment of the present invention provides a method for calculating power device losses, wherein the power device includes an IGBT and a diode. The method includes:

[0005] Obtaining a system current and an ambient temperature of a circuit system in which the power device is located;

[0006] Based on the ambient temperature, extracting a first performance curve of the IGBT and a second performance curve of the diode respectively;

[0007] Calculating the loss of the IGBT based on the system current and the first performance curve to obtain a first loss result;

[0008] Calculating the loss of the diode based on the system current and the second performance curve to obtain a second loss result;

[0009] The total loss of the power device is calculated based on the system current, the first loss result, and the second loss result.

[0010] Optionally, the calculating the loss of the IGBT based on the system current and the first performance curve to obtain a first loss result includes:

[0011] determining a first switching state and a first on-time of the IGBT based on the first performance curve;

[0012] calculating, according to the first performance curve, a switching loss of the IGBT based on the system current and the first switching state;

[0013] Calculating a first conduction loss of the IGBT according to the first performance curve, based on the system current and the first conduction time;

[0014] A first loss result is calculated based on the switching loss and the first conduction loss.

[0015] Optionally, the calculating the loss of the diode based on the system current and the second performance curve to obtain a second loss result includes:

[0016] determining a second switching state and a second conduction time of the diode based on the second performance curve;

[0017] calculating, according to the second performance curve, a turn-off loss of the diode based on the system current and the second switch state;

[0018] calculating, according to the second performance curve, a second conduction loss of the diode based on the system current and the conduction time;

[0019] A second loss result is calculated based on the turn-off loss and the second turn-on loss.

[0020] Optionally, calculating the total loss of the power device based on the system current, the first loss result, and the second loss result includes:

[0021] According to a preset modulation algorithm, the first loss result and the second loss result within one modulation period are accumulated based on the system current to calculate the total loss of the power device.

[0022] Optionally, the method includes accumulating the first loss result and the second loss result within one modulation period based on the system current according to the modulation algorithm to calculate the total loss of the power device, and the method includes:

[0023] Obtaining modulation parameters of the preset modulation algorithm;

[0024] determining a modulation period based on the system current;

[0025] Based on the modulation parameter and the modulation period, modulating the first loss result and the second loss result respectively to obtain a first modulation result and a second modulation result respectively;

[0026] The first modulation result and the second modulation result within the modulation period are accumulated to obtain a total loss of the power device.

[0027] Optionally, the modulation parameters include: duty cycle, carrier ratio, switching state and switching frequency of the IGBT.

[0028] Optionally, the method further includes:

[0029] Calculating a junction temperature of the power device based on the total loss and thermal resistance of the power device;

[0030] updating the ambient temperature using the junction temperature;

[0031] Based on the updated ambient temperature and the current system current of the circuit system, the process returns to the step of respectively extracting the first performance curve of the IGBT and the second performance curve of the diode based on the ambient temperature.

[0032] According to a second aspect, an embodiment of the present invention provides a power device loss calculation device, wherein the power device includes an IGBT and a diode, and the device includes:

[0033] an acquisition module, configured to acquire a system current and an ambient temperature of a circuit system in which the power device is located;

[0034] an extraction module, configured to extract a first performance curve of the IGBT and a second performance curve of the diode based on the ambient temperature;

[0035] A first processing module, configured to calculate the loss of the IGBT based on the system current and the first performance curve to obtain a first loss result;

[0036] a second processing module, configured to calculate the loss of the diode based on the system current and the second performance curve to obtain a second loss result;

[0037] A third processing module is configured to calculate a total loss of the power device based on the system current, the first loss result, and the second loss result.

[0038] According to a third aspect, an embodiment of the present invention provides an electronic device, including:

[0039] A memory and a processor, wherein the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the method described in the first aspect or any optional embodiment of the first aspect by executing the computer instructions.

[0040] According to a fourth aspect, an embodiment of the present invention provides a computer-readable storage medium, wherein the computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a computer to execute the method described in the first aspect or any optional embodiment of the first aspect.

[0041] The technical solution of the present invention has the following advantages:

[0042] The power device loss calculation method and apparatus provided by the present invention obtain the system current and ambient temperature of the circuit system in which the power device is located; based on the ambient temperature, extract the first performance curve of the IGBT and the second performance curve of the diode; calculate the loss of the IGBT based on the system current and the first performance curve to obtain a first loss result; calculate the loss of the diode based on the system current and the second performance curve to obtain a second loss result; and calculate the total loss of the power device based on the system current, the first loss result, and the second loss result. By calculating the loss results of the IGBT and the diode according to their respective performance curves, and calculating the total loss of the power device based on the loss results of the IGBT and the diode and the system current of the power device, the accuracy of the power device loss calculation is improved while also dynamically calculating the loss situation, providing strong data support for better evaluation of the working efficiency of the power device. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0044] Figure 1 Flowchart of a method for calculating power device loss according to an embodiment of the present invention;

[0045] Figure 2 The IGBT and diode operating characteristic curves of the power device loss calculation method according to an embodiment of the present invention;

[0046] Figure 3 A diagram showing the working principle of a loss model of a method for calculating power device loss according to an embodiment of the present invention;

[0047] Figure 4 Schematic diagram of the structure of a power device loss calculation device according to an embodiment of the present invention;

[0048] Figure 5 The figure is a schematic structural diagram of an electronic device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0049] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0050] In the description of the present invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate and simplify the description of the present invention. They are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation, and therefore should not be construed as limiting the present invention. Furthermore, the terms "first," "second," "third," and "fourth" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0051] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; internal connections between two components; wireless connections or wired connections. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0052] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0053] The embodiment of the present invention provides a method for calculating power device loss, wherein the power device includes an IGBT and a diode. Figure 1 As shown, the power device loss calculation method specifically includes the following steps:

[0054] Step S101: obtaining the system current and the ambient temperature of the circuit system where the power device is located.

[0055] Exemplarily, the power device may be a frequency converter.

[0056] Step S102: extracting a first performance curve of the IGBT and a second performance curve of the diode based on the ambient temperature.

[0057] Specifically, in practical applications, the ambient temperature is a benchmark value. On this basis, the system loss (i.e., the loss of power devices including IGBTs and diodes) will cause the heat dissipation system to rise in temperature. The higher the temperature, the more the switching characteristic curve of the power device will change, thereby affecting the loss of the device.

[0058] Specifically, if Figure 2 As shown, Figure 2 The above figure is the first performance curve of IGBT. Figure 2 The figure below shows the second performance curve for a diode, where the solid line represents the voltage curve and the dashed line represents the current curve. When power devices operate at different power levels, the corresponding performance curves for the IGBT and diode also change accordingly. The values ​​of the parameters in the performance curves are determined by the output and operating state of the circuit system.

[0059] Step S103: Calculate the loss of the IGBT based on the system current and the first performance curve to obtain a first loss result.

[0060] Specifically, in practical applications, the first loss result of the IGBT includes switching loss and first conduction loss. The embodiment of the present invention calculates the first loss of the IGBT based on the first performance curve, laying the foundation for calculating the power device loss under different dynamic parameters.

[0061] Step S104: Calculate the loss of the diode based on the system current and the second performance curve to obtain a second loss result.

[0062] Specifically, in practical applications, the second loss result of the diode includes turn-off loss and second conduction loss. The embodiment of the present invention calculates the second loss of the diode according to the second performance curve, laying the foundation for calculating the power device loss under different dynamic parameters.

[0063] Step S105: Calculate the total loss of the power device based on the system current, the first loss result, and the second loss result.

[0064] Specifically, in practical applications, taking the inverter as an example, the loss of the inverter is affected by multi-dimensional parameters, including conduction current, bus voltage, heat dissipation efficiency, loop parasitic parameters, etc. Therefore, the first issue in loss analysis is to establish accurate relationships among these influencing dimensions and realize loss calculation under different dynamic parameters in turn.

[0065] The embodiment of the present invention calculates the loss of power devices through a loss model, such as Figure 3As shown in the figure, the functional area can be divided into four parts: "device loss", "algorithm modulation", "system loss" and "heat dissipation system". Among them, the "heat dissipation system" is the cooling system, which ensures that the ambient temperature of the power device is stable and avoids failure of the power device due to rising junction temperature; "device loss" is divided into switching loss and conduction loss of IGBT and turn-off loss and conduction loss of diode; "algorithm modulation" provides parameters such as IGBT switching state, duty cycle, carrier, carrier ratio, switching frequency, etc.; "system loss" can obtain the total loss of the power device, that is, the loss of the system, by accumulating the first loss result and the second loss result.

[0066] Among them, U CE It is the voltage that the power device withstands when it is turned off, which is related to the bus voltage setting value of the circuit system and is an input constant in the loss model; Le is the stray inductance of the power circuit of the system and is an input constant in the loss model; Tvj is the ambient temperature fed back by the heat dissipation system. The initial quantity of the loss model is set to the ambient temperature. In the continuous loss calculation iteration, its value is continuously updated, and considering that the thermal resistance equivalent circuit of the heat dissipation system is suitable for steady-state junction temperature estimation, the junction temperature fed back by the heat dissipation system is calculated and updated with each modulation cycle as the unit time; I is the output current of the system, which is constantly adjusted by the modulation algorithm and is continuously updated, and constantly affects the calculation of device losses, where I is the current in the system (when the IGBT is turned on, I is I C , the diode conducts I is I F );t PWM The on-duty cycle of each device; f sw is the switching frequency of the switching device; Ex is the loss generated by a single conduction of the device, including switching loss and conduction loss.

[0067] By executing the above steps, the power device loss calculation method provided in the embodiment of the present invention calculates the loss results of the IGBT and the diode respectively according to their respective performance curves. Based on the loss results of the IGBT and the diode, combined with the system current of the power device, the total loss of the power device is calculated. While improving the accuracy of calculating the power device loss, the loss situation is also dynamically calculated, providing strong data support for better evaluation of the working efficiency of the power device.

[0068] Specifically, in one embodiment, the above step S103 calculates the loss of the IGBT based on the system current and the first performance curve to obtain a first loss result, which specifically includes the following steps:

[0069] Step S201: Determine a first switching state and a first on-time of the IGBT based on a first performance curve.

[0070] Step S202: Calculate the switching loss of the IGBT according to the first performance curve, based on the system current and the first switching state.

[0071] Step S203: Calculate and obtain a first conduction loss of the IGBT according to the first performance curve, based on the system current and the first conduction time.

[0072] Step S204: Calculate and obtain a first loss result based on the switching loss and the first conduction loss.

[0073] Specifically, in practical applications, Figure 2 As shown in the figure, the present invention divides the switching loss calculation of an IGBT into eight time points: t1 to t4 represents the IGBT's turn-on process; t4 to t5 represents the IGBT's conduction process; and t5 to t8 represents the IGBT's turn-off process. These time periods must be calibrated based on test waveforms at different junction temperatures and currents to enable loss calculation under different operating conditions.

[0074] At time t1, the gate voltage of the IGBT exceeds the conduction threshold, the IGBT starts to conduct and enters the linear working area, and the conduction current I C begins to rise, and at the same time the diode conduction current I F The current change rate di / dt remains basically unchanged, and the IGBT on-state current expression during the time period t1 to t2 is:

[0075]

[0076] During the current rise, due to the presence of stray inductance Le in the loop, a ΔUce is generated across the collector and emitter of the IGBT. The expression of the IGBT collector-emitter voltage during the period t1 to t2 is:

[0077]

[0078] At time t2, the diode current drops to 0 and enters the reverse recovery stage of the diode. The IGBT on-state current expression in the time period t2 to t3 is:

[0079]

[0080] Where Irm is the peak current of the diode reverse current recovery.

[0081] At this stage, the reverse voltage drop of the diode is very small, so the loss of the diode can be ignored, and the collector-emitter voltage of the IGBT remains basically unchanged:

[0082] u ce23 (t) = u ce12 (t) (4)

[0083] During the time period from t3 to t4, the IGBT on-state current decays from the peak value to the on-state current Ic, and the collector voltage drops to 0. The expressions of the IGBT on-state current and collector-emitter voltage in this stage are:

[0084]

[0085]

[0086] According to equations (1) to (8), the expression of IGBT turn-on loss is:

[0087]

[0088] At t5, the gate drive signal of the IGBT is lower than the conduction threshold, and the IGBT begins to enter the off state. The collector-emitter voltage of the IGBT gradually increases; the reverse voltage of the diode decreases, but it is still in the reverse cutoff state. Therefore, the on-state current of the IGBT basically maintains the on-state current I C The on-state current and collector-emitter voltage of the IGBT during the period t5 to t6 are expressed as follows:

[0089] i c56 (t) = I c (8)

[0090]

[0091] At t6, the collector-emitter voltage of the IGBT rises to Uce, the reverse voltage of the diode drops to 0, and the diode begins to conduct forward. The on-current of the IGBT begins to decrease. The on-current expression of the IGBT in the time period t6 to t7 is:

[0092]

[0093] Since there is stray inductance in the commutation circuit, when the current in the circuit changes, it will induce

[0094] ΔU ce2 Superimposed on the collector and emitter of the IGBT, the expression of the IGBT collector voltage during the period t6 to t7 is:

[0095]

[0096] At t7, the on-current of the IGBT drops to 0.1I C Since a large amount of excess carrier charge accumulates in the IGBT base region, it takes a long time for the excess carriers to recombine after the IGBT is turned off, that is, the tail current time t tail The on-state current expression of the IGBT during the period t7 to t8 is:

[0097]

[0098] At this time, the collector-emitter voltage of the IGBT decreases, and du / dt gradually decreases to 0. Therefore, the collector-emitter voltage of the IGBT in the time period t7 to t8 decreases exponentially, and the expression is:

[0099]

[0100] According to equations (8) to (13), the turn-off loss of IGBT is expressed as:

[0101]

[0102] In summary, the expression of the switching loss Esw of IGBT in one switching cycle is:

[0103] E sw =E on +E off (15)

[0104] Specifically, the first conduction loss of the IGBT is calculated with reference to the prior art, which will not be described in detail here.

[0105] By adding the switching loss and the first conduction loss, the first loss result of the IGBT is calculated. In practical applications, the current working state of the IGBT is obtained through the first performance curve of the IGBT, and the loss of the IGBT is calculated based on the current working state. When the circuit system changes, the working state of the IGBT under different load states can also be grasped, and its loss can be accurately calculated, providing strong data support for the subsequent realization of the impact of various algorithms, different types of power devices, heat dissipation design and other aspects on the overall working efficiency of the product.

[0106] Specifically, in one embodiment, the step S103 calculates the loss of the diode based on the system current and the second performance curve to obtain a second loss result, which specifically includes the following steps:

[0107] Step S301: Determine a second switching state and a second conduction time of a diode based on a second performance curve.

[0108] Step S302: Calculate the turn-off loss of the diode according to the second performance curve, based on the system current and the second switch state.

[0109] Step S303: Calculate and obtain a second conduction loss of the diode according to the second performance curve, based on the system current and the conduction time.

[0110] Step S304: Calculate and obtain a second loss result based on the turn-off loss and the second turn-on loss.

[0111] Specifically, in practical applications, Figure 2 As shown in the figure, at time t3, the PN junction charge of the diode is depleted and begins to withstand reverse voltage, which gradually rises to Uce. The reverse current of the diode begins to gradually decrease, and di / dt also gradually decreases to 0, so the reverse recovery current of the diode decreases exponentially from the peak value of the reverse recovery current Irm to 0. During the period t3 to t4, the expressions of the reverse current and voltage of the diode are:

[0112]

[0113]

[0114] According to equations (1) to (8), the turn-off loss of the diode is expressed as:

[0115]

[0116] Specifically, the second conduction loss of the diode is calculated with reference to the prior art, which will not be described in detail here.

[0117] By adding the turn-off loss and the second conduction loss, the second loss result of the diode is calculated. In practical applications, the current working state of the diode is obtained through the second performance curve of the diode, and the loss of the diode is calculated based on the current working state. Even if the circuit system changes, the working state of the diode under different load conditions can be grasped, and its loss can be accurately calculated. This provides strong data support for the subsequent implementation of the impact of various algorithms, different types of power devices, heat dissipation design and other aspects on the overall working efficiency of the product.

[0118] Specifically, in one embodiment, the above step S105 calculates the total loss of the power device based on the system current, the first loss result, and the second loss result, and specifically includes the following steps:

[0119] Step S401: According to a preset modulation algorithm, a first loss result and a second loss result within a modulation period are accumulated based on the system current to calculate the total loss of the power device.

[0120] Specifically, in actual applications, during the loss calculation process, it is necessary to modulate it according to a preset modulation algorithm to obtain the performance curve and corresponding operating parameters required by technicians, and calculate the losses of IGBTs and diodes based on specific performance curves and operating parameters. Finally, the total loss of the power device is calculated, which greatly improves the flexibility of the power device loss calculation.

[0121] Specifically, in one embodiment, the above step S401 specifically includes the following steps:

[0122] Step S501: Acquire modulation parameters of a preset modulation algorithm.

[0123] Specifically, in practical applications, modulation parameters include the modulation frequency, the IGBT's duty cycle, carrier ratio, and switching state, as well as the switching frequency determined based on the modulation frequency. Furthermore, additional modulation parameters can be added based on actual conditions, for example, to provide algorithmic support for subsequent loss calculations based on a preset modulation algorithm.

[0124] Step S502: determining a modulation period based on the system current.

[0125] Specifically, in practical applications, the modulation period is determined by the current frequency output by the system. For example, if the current is output at 1 kHz, the modulation period is 1 ms.

[0126] Step S503: Based on the modulation parameters and the modulation period, the first loss result and the second loss result are modulated respectively to obtain a first modulation result and a second modulation result respectively.

[0127] Specifically, in practical applications, algorithm modulation is accompanied by the overall loss calculation process, that is, modulation and calculation are performed simultaneously, thereby achieving dynamic adjustment of the overall loss.

[0128] Step S504: Accumulate the first modulation result and the second modulation result within the modulation period to obtain the total loss of the power device.

[0129] Specifically, in practical applications, the embodiment of the present invention accumulates the losses within a modulation period according to the carrier ratio, thereby obtaining the total loss of the power device.

[0130] Specifically, in one embodiment, after executing the above step S105, the following steps are further included:

[0131] Step S601: Calculating the junction temperature of the power device based on the total loss and thermal resistance of the power device.

[0132] Step S602: Update the ambient temperature using the junction temperature.

[0133] Step S603: Based on the updated ambient temperature and the current system current of the circuit system, return to the above step S102 to extract the first performance curve of the IGBT and the second performance curve of the diode based on the ambient temperature.

[0134] Specifically, in practical applications, Figure 3As shown, the embodiment of the present invention obtains the power loss of the power device according to the modulation frequency, estimates the junction temperature of the power device according to the thermal resistance and the ambient temperature, and uses the estimated junction temperature as the new ambient temperature. Subsequently, the power device loss calculation will be performed based on the updated ambient temperature. By continuously updating the numerical value, the accuracy of the power device loss is further improved.

[0135] The power device loss calculation method provided by the embodiment of the present invention will be described in detail below with reference to specific application examples.

[0136] Combine Figure 1-Figure 3 As shown in the figure, taking the inverter as an example, the loss of the inverter is affected by multi-dimensional parameters, including conduction current, bus voltage, heat dissipation efficiency, loop parasitic parameters, etc. Therefore, the first issue in loss analysis is to establish an accurate relationship among these influencing dimensions and realize the loss calculation under different dynamic parameters in turn.

[0137] The embodiment of the present invention calculates the loss of power devices through a loss model, such as Figure 2 As shown, the functional areas can be divided into four parts: "device loss", "algorithm modulation", "system loss" and "heat dissipation system". Among them, "device loss" is divided into switching loss and conduction loss of IGBT and turn-off loss and conduction loss of diode; "algorithm modulation" provides parameters such as IGBT switching state, duty cycle, carrier, carrier ratio, switching frequency, etc.; "system loss" can obtain the total loss of power devices and then the loss of the system by adding the first loss result and the second loss result. The "heat dissipation system" obtains the junction temperature of each device through the system's loss and thermal resistance calculation model, and feeds it back to the "device loss"; "device loss" generates new device loss values ​​based on the updated junction temperature data... and so on. The overall operation flow chart of this model is shown below. Figure 3 As shown. Uce is related to the system's bus voltage setpoint and is an input constant in the loss model. Le is the system's power circuit stray inductance and is also an input constant in the loss model. Tvj is the ambient temperature fed back by the cooling system. The initial value of the loss model is set to the ambient temperature and its value is continuously updated during the continuous loss calculation iterations. Furthermore, the junction temperature fed back by the cooling system is calculated and updated per modulation cycle. This is because the thermal resistance equivalent circuit of the cooling system is suitable for steady-state junction temperature estimation. I is the system's output current, which is constantly adjusted by the modulation algorithm, is continuously updated, and continuously affects the calculation of device losses.

[0138] Through the above steps, the embodiment of the present invention can accurately and independently evaluate the performance of power devices, better understand the working status of power devices under different load conditions, and further provide strong data support for the impact of various algorithms, different types of power devices, heat dissipation design and other aspects on the overall working efficiency of the product.

[0139] The embodiment of the present invention provides a power device loss calculation device, the power device includes an IGBT and a diode, such as Figure 4 As shown, the power device loss calculation device includes:

[0140] The acquisition module 101 is used to acquire the system current and the ambient temperature of the circuit system in which the power device is located. For details, please refer to the relevant description of step S101 in the above method embodiment, which will not be repeated here.

[0141] The extraction module 102 is used to extract the first performance curve of the IGBT and the second performance curve of the diode based on the ambient temperature. For details, please refer to the relevant description of step S102 in the above method embodiment, which will not be repeated here.

[0142] The first processing module 103 is used to calculate the loss of the IGBT based on the system current and the first performance curve to obtain a first loss result. For details, please refer to the relevant description of step S103 in the above method embodiment, which will not be repeated here.

[0143] The second processing module 104 is used to calculate the loss of the diode based on the system current and the second performance curve to obtain a second loss result. For details, please refer to the relevant description of step S104 in the above method embodiment, which will not be repeated here.

[0144] The third processing module 105 is configured to calculate the total loss of the power device based on the system current, the first loss result, and the second loss result. Detailed information can be found in the description of step S105 in the above method embodiment, which will not be repeated here.

[0145] For further description of the above-mentioned power device loss calculation apparatus, please refer to the relevant description of the above-mentioned power device loss calculation method embodiment, which will not be repeated here.

[0146] Through the coordinated cooperation of the above-mentioned components, the power device loss calculation device provided in the embodiment of the present invention calculates the loss results of the IGBT and the diode respectively according to their respective performance curves. Based on the loss results of the IGBT and the diode, combined with the system current of the power device, the total loss of the power device is calculated. While improving the accuracy of calculating the loss of the power device, the loss situation is also dynamically calculated, providing strong data support for better evaluation of the working efficiency of the power device.

[0147] An embodiment of the present invention provides an electronic device, such as Figure 5 As shown, the electronic device includes a processor 901 and a memory 902, and the memory 902 and the processor 901 are communicatively connected to each other, wherein the processor 901 and the memory 902 can be connected via a bus or other means. Figure 5 The bus connection is taken as an example.

[0148] The processor 901 may be a central processing unit (CPU). The processor 901 may also be other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or a combination of the above chips.

[0149] Memory 902, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs, non-transitory computer executable programs, and modules, such as the program instructions / modules corresponding to the methods in the embodiments of the present invention. Processor 901 executes the non-transitory software programs, instructions, and modules stored in memory 902 to perform various functional applications and data processing of processor 901, thereby implementing the methods in the above-mentioned method embodiments.

[0150] The memory 902 may include a program storage area and a data storage area, wherein the program storage area may store an operating system and application programs required for at least one function; the data storage area may store data created by the processor 901, etc. In addition, the memory 902 may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one disk storage device, a flash memory device, or other non-volatile solid-state storage device. In some embodiments, the memory 902 may optionally include a memory remotely located relative to the processor 901, and these remote memories may be connected to the processor 901 via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0151] One or more modules are stored in the memory 902 and, when executed by the processor 901 , perform the method in the above method embodiment.

[0152] The specific details of the above electronic device can be understood by referring to the corresponding descriptions and effects in the above method embodiments, and will not be repeated here.

[0153] Those skilled in the art will appreciate that all or part of the processes in the above-described embodiments can be implemented by instructing related hardware through a computer program. The implemented program can be stored in a computer-readable storage medium. When the program is executed, it can include the processes of the above-described embodiments. The storage medium can be a magnetic disk, an optical disk, a read-only memory (ROM), a random access memory (RAM), a flash memory, a hard disk drive (HDD), or a solid-state drive (SSD). The storage medium can also include a combination of the above-mentioned types of memory.

[0154] Obviously, the above embodiments are merely examples for clarity of explanation and are not intended to limit the implementation methods. Those skilled in the art will readily appreciate that other variations or modifications based on the above descriptions are possible. It is not necessary and impossible to enumerate all implementation methods here. Obvious variations or modifications arising therefrom remain within the scope of protection of the present invention.

Claims

1. A method for calculating power device loss, characterized in that: The power device includes an IGBT and a diode, and the method includes: Obtaining a system current and an ambient temperature of a circuit system in which the power device is located; Based on the ambient temperature, extracting a first performance curve of the IGBT and a second performance curve of the diode respectively, wherein the ambient temperature affects the performance curve of the power device; Calculating the loss of the IGBT based on the system current and the first performance curve to obtain a first loss result, where the first loss result includes a switching loss and a first conduction loss; Calculating the loss of the diode based on the system current and the second performance curve to obtain a second loss result; Calculating a total loss of the power device based on the system current, the first loss result, and the second loss result; The calculating the total loss of the power device based on the system current, the first loss result, and the second loss result includes: accumulating the first loss result and the second loss result within a modulation cycle based on the system current according to a preset modulation algorithm to calculate the total loss of the power device; The method comprises: obtaining a modulation parameter of the preset modulation algorithm; determining a modulation period based on the system current; modulating the first loss result and the second loss result based on the modulation parameter and the modulation period to obtain a first modulation result and a second modulation result, respectively; and accumulating the first modulation result and the second modulation result within the modulation period to obtain the total loss of the power device; The method further comprises: Calculating a junction temperature of the power device based on the total loss and thermal resistance of the power device; updating the ambient temperature using the junction temperature; Based on the updated ambient temperature and the current system current of the circuit system, the process returns to the step of respectively extracting the first performance curve of the IGBT and the second performance curve of the diode based on the ambient temperature.

2. The method according to claim 1, characterized in that The calculating the loss of the IGBT based on the system current and the first performance curve to obtain a first loss result includes: determining a first switching state and a first on-time of the IGBT based on the first performance curve; calculating, according to the first performance curve, a switching loss of the IGBT based on the system current and the first switching state; Calculating a first conduction loss of the IGBT according to the first performance curve, based on the system current and the first conduction time; A first loss result is calculated based on the switching loss and the first conduction loss.

3. The method according to claim 1, characterized in that The calculating the loss of the diode based on the system current and the second performance curve to obtain a second loss result includes: determining a second switching state and a second conduction time of the diode based on the second performance curve; calculating, according to the second performance curve, a turn-off loss of the diode based on the system current and the second switch state; calculating, according to the second performance curve, a second conduction loss of the diode based on the system current and the conduction time; A second loss result is calculated based on the turn-off loss and the second turn-on loss.

4. The method according to claim 1, wherein The modulation parameters include: modulation frequency, IGBT duty cycle, carrier ratio and switching state.

5. A power device loss calculation device, characterized in that: The power device includes an IGBT and a diode, and the device includes: an acquisition module, configured to acquire a system current and an ambient temperature of a circuit system in which the power device is located; an extraction module, configured to extract, based on the ambient temperature, a first performance curve of the IGBT and a second performance curve of the diode, respectively, wherein the ambient temperature affects the performance curve of the power device; a first processing module, configured to calculate the loss of the IGBT based on the system current and the first performance curve to obtain a first loss result, where the first loss result includes a switching loss and a first conduction loss; a second processing module, configured to calculate the loss of the diode based on the system current and the second performance curve to obtain a second loss result; a third processing module, configured to calculate a total loss of the power device based on the system current, the first loss result, and the second loss result; The calculating the total loss of the power device based on the system current, the first loss result, and the second loss result includes: accumulating the first loss result and the second loss result within a modulation cycle based on the system current according to a preset modulation algorithm to calculate the total loss of the power device; The calculating the total loss of the power device by accumulating the first loss result and the second loss result within a modulation period based on the system current according to a preset modulation algorithm includes: obtaining a modulation parameter of the preset modulation algorithm; determining a modulation period based on the system current; modulating the first loss result and the second loss result based on the modulation parameter and the modulation period to obtain a first modulation result and a second modulation result, respectively; and accumulating the first modulation result and the second modulation result within the modulation period to obtain the total loss of the power device; Calculating a junction temperature of the power device based on the total loss and thermal resistance of the power device; updating the ambient temperature using the junction temperature; Based on the updated ambient temperature and the current system current of the circuit system, the process returns to the step of respectively extracting the first performance curve of the IGBT and the second performance curve of the diode based on the ambient temperature.

6. An electronic device, characterized in that: include: A memory and a processor, wherein the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the method according to any one of claims 1 to 4 by executing the computer instructions.

7. A computer-readable storage medium, characterized in that The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a computer to execute the method according to any one of claims 1 to 4.

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