A temperature control method, device and medium for MOS tubes in a DC / DC converter

Abstract

The application discloses a temperature control method, device and medium of MOS tubes in a DC / DC converter, and the method comprises the following steps: collecting temperature data and current data of a plurality of MOS tubes in the DC / DC converter respectively; determining temperature difference data between a single MOS tube and average temperature of the plurality of MOS tubes according to a preset temperature control period; determining a current compensation value of the single MOS tube according to the temperature difference data; outputting a duty cycle of the single MOS tube according to the current compensation value, the current data and a preset current expected value according to a preset current control period; and performing opening and closing actions of the single MOS tube according to the duty cycle. The temperature of the plurality of MOS tubes is balanced, the current of one MOS tube is reduced when the temperature of the MOS tube is too high, and the currents of other MOS tubes are increased. Therefore, the temperature of the MOS tube is reduced, and the total current is not affected.

Description

Technical Field

[0001] This application relates to the field of circuit control, specifically to a method, device, and medium for temperature control of a MOSFET in a DC / DC converter. Background Technology

[0002] A DC / DC converter is a voltage converter that transforms the input voltage and effectively outputs a fixed voltage; in circuit classification, it belongs to the chopper circuit category. Currently, SiC MOSFETs are typically chosen as the switching transistors in fuel cell DC / DC converters due to their advantages such as high switching frequency and low conduction loss. Since using a single MOSFET results in low current and large current ripple, multiple MOSFETs are now commonly used in an interleaved parallel control configuration to achieve high current and low ripple.

[0003] Temperature deviations in MOSFETs can be caused by factors such as differences in power devices, current sensors, water-cooling design, and installation processes. When there is a large temperature difference in a MOSFET, the current of the MOSFET will be limited, causing the DC / DC converter to be unable to output full power, or even burning out the MOSFET. Summary of the Invention

[0004] To address the aforementioned problems, this application proposes a temperature control method, apparatus, and dielectric for a MOSFET in a DC / DC converter, wherein the method includes:

[0005] Temperature and current data of multiple MOSFETs in the DC / DC converter are collected respectively; according to a preset temperature control cycle, the temperature difference between a single MOSFET and the average temperature of the multiple MOSFETs is determined; based on the temperature difference data, the current compensation value of the single MOSFET is determined; according to a preset current control cycle, based on the current compensation value, the current data, and a preset expected current value, the duty cycle of the single MOSFET is output; based on the duty cycle, the switching action of the single MOSFET is executed.

[0006] In one example, determining the temperature difference data between a single MOSFET and the average temperature of the plurality of MOSFETs according to a preset temperature control cycle specifically includes: determining the average temperature of the plurality of MOSFETs based on the temperature data of the plurality of MOSFETs; randomly selecting a single MOSFET from the plurality of MOSFETs, and determining the intermediate temperature difference data between the single MOSFET and the average temperature based on the temperature data of the single MOSFET; determining whether the intermediate temperature difference data exceeds a preset temperature threshold; if it exceeds the threshold, then using the intermediate temperature difference data as the temperature difference data; if it does not exceed the threshold, then considering the temperature difference data to be non-existent.

[0007] In one example, determining the current compensation value of a single MOSFET based on the temperature difference data specifically includes: determining the current compensation value corresponding to the temperature difference data by integrating the temperature difference data; the integration calculation specifically includes: determining the current compensation value of a single MOSFET using the following formula: Among them, I com K is the current compensation value. p T is the first preset scaling factor. i For the temperature control cycle, T diff (t) represents the temperature difference over time t, and c is a preset constant.

[0008] In one example, the step of outputting the duty cycle of a single MOSFET according to a preset current control cycle, based on the current compensation value, the current data, and a preset current expectation value, specifically includes: determining the current difference of the single MOSFET based on the current data, the current expectation value, and the current compensation value; determining the intermediate duty cycle of the single MOSFET using the current difference; determining whether the intermediate duty cycle exceeds a preset ratio value; if it does not exceed the preset ratio value, then using the intermediate duty cycle as the duty cycle of the single MOSFET; if it exceeds the preset ratio value, then using the preset ratio value as the duty cycle of the single MOSFET.

[0009] In one example, determining the current difference of a single MOSFET based on the current data, the expected current value, and the current compensation value specifically includes: determining the current difference using the following formula: I diff =I ref -I real +I com Among them, I diff I is the current difference. ref I is the desired current value. real This represents the actual current value corresponding to the current data.

[0010] In one example, determining the intermediate duty cycle of a single MOSFET using the current difference specifically includes calculating the intermediate duty cycle using the following formula: Where U(t) is the intermediate duty cycle, K m I is the second preset proportional coefficient. diff (t) is a function of the current difference with respect to time t, where T l For the current control cycle, I diff′ (t) is I diff The derivative of (t).

[0011] In one example, the step of collecting temperature data of multiple MOSFETs in the DC / DC converter specifically includes: acquiring the temperature data corresponding to each of the multiple MOSFETs by using multiple temperature sensors respectively disposed on one side of the multiple MOSFETs.

[0012] In one example, the duration of the temperature control cycle is shorter than the duration of the current control cycle.

[0013] This application also provides a temperature control device for MOSFETs in a DC / DC converter, comprising: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to enable the at least one processor to perform: acquiring temperature data and current data of multiple MOSFETs in the DC / DC converter respectively; determining temperature difference data between a single MOSFET and the average temperature of the multiple MOSFETs according to a preset temperature control cycle; determining a current compensation value for the single MOSFET based on the temperature difference data; outputting the duty cycle of the single MOSFET according to the current compensation value, the current data, and a preset current expectation value according to a preset current control cycle; and performing the switching action of the single MOSFET according to the duty cycle.

[0014] This application also provides a non-volatile computer storage medium storing computer-executable instructions, wherein the computer-executable instructions are configured to: collect temperature data and current data of multiple MOSFETs in a DC / DC converter respectively; determine the temperature difference data between a single MOSFET and the average temperature of the multiple MOSFETs according to a preset temperature control cycle; determine the current compensation value of the single MOSFET based on the temperature difference data; output the duty cycle of the single MOSFET according to the current compensation value, the current data, and a preset current expectation value according to a preset current control cycle; and execute the switching action of the single MOSFET according to the duty cycle.

[0015] The method proposed in this application offers the following advantages: it achieves temperature balance among multiple MOSFETs; when the temperature of one MOSFET is too high, it reduces the current of that MOSFET while increasing the current of the other MOSFETs. This reduces the temperature of the MOSFET without affecting the overall current. It avoids situations where a large temperature difference among the MOSFETs, leading to a DC / DC converter reporting an over-temperature fault and causing shutdown or current limiting, would occur if one MOSFET's temperature is too high. Attached Figure Description

[0016] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0017] Figure 1 This is a schematic diagram of the topology of a DC / DC converter according to an embodiment of this application;

[0018] Figure 2 This is a flowchart illustrating a method for temperature control of a MOSFET in a DC / DC converter according to an embodiment of this application.

[0019] Figure 3 This is a schematic diagram of the structure of a temperature control device for a MOS transistor in a DC / DC converter according to an embodiment of this application. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0021] The technical solutions provided by the various embodiments of this application are described in detail below with reference to the accompanying drawings.

[0022] Figure 1 This diagram illustrates a topology of a DC / DC converter provided in one or more embodiments of this specification. Using four MOSFETs as an example, the DC / DC converter includes an input precharge module (K1 and K2 are relays, R1 is a precharge group, and V1 and V2 are voltage sensors), an output precharge module (K3 and K4 are relays, R2 is a precharge group, and V3 and V4 are voltage sensors), and a boost module. The boost module requires four interleaved boost converters connected in parallel (this can be expanded or reduced as needed). G1, G2, G3, and G4 are SiC MOSFETs in the boost circuit, A represents four current sensors, and C represents a capacitor.

[0023] In one embodiment, this application provides a temperature sensor on each MOSFET.

[0024] Figure 2This is a schematic flowchart illustrating a method for temperature control of a MOSFET in a DC / DC converter, provided for one or more embodiments of this specification. This method can be applied to fuel cell DC / DC converters. The process can be executed by a computing device in the relevant field, and certain input parameters or intermediate results in the process can be manually adjusted to help improve accuracy.

[0025] The analysis method involved in the embodiments of this application can be implemented by a terminal device or a server, and this application does not impose any special limitations on it. For ease of understanding and description, the following embodiments are all described in detail using a microprocessor as an example.

[0026] like Figure 2 As shown, this application embodiment provides a temperature control method for a MOSFET in a DC / DC converter, including:

[0027] S101: Collects temperature and current data of multiple MOSFETs in the DC / DC converter respectively.

[0028] First, temperature and current data of multiple MOSFETs within the DC / DC converter are collected. These temperature and current data refer to the current temperatures and current values ​​of the multiple MOSFETs, respectively. During data acquisition, multiple temperature sensors positioned on one side of each MOSFET can be used to obtain the individual temperature data for each MOSFET.

[0029] S102: Determine the temperature difference data between a single MOS transistor and the average temperature of the plurality of MOS transistors according to a preset temperature control cycle.

[0030] After collecting temperature data from multiple MOSFETs, if the temperature control cycle is reached, the temperature difference between any one MOSFET and the average temperature of all MOSFETs is determined based on the temperature data. Here, the temperature difference refers to the temperature difference value.

[0031] In one embodiment, when determining the temperature difference between a single MOSFET and the average temperature of multiple MOSFETs, the average temperature of the multiple MOSFETs is first determined based on their temperature data. Then, a single MOSFET is randomly selected from the multiple MOSFETs, and the intermediate temperature difference between the single MOSFET and the average temperature is determined based on its temperature data. Finally, it is determined whether the intermediate temperature difference exceeds a preset temperature threshold. If it does, the intermediate temperature difference is used as the actual temperature difference; otherwise, it is considered that the temperature difference does not exist, i.e., the temperature difference value is 0. In other words, if the temperature difference value does not exceed the preset temperature threshold, the temperature of the MOSFET does not need to be adjusted.

[0032] S103: Determine the current compensation value of the single MOS transistor based on the temperature difference data.

[0033] After obtaining the temperature difference data for each MOSFET, if the temperature difference is too high, it may cause the DC / DC converter to report an over-temperature fault, leading to shutdown or current limiting, while other MOSFETs may not reach their carrying capacity. Therefore, it is necessary to reduce the temperature value of individual MOSFETs by reducing the current flowing through them, thereby reducing the temperature difference. At this point, the current compensation value for each MOSFET can be determined using the temperature difference data.

[0034] In one embodiment, when determining the current compensation value of a single MOSFET based on the temperature difference data, the current compensation value corresponding to the temperature difference data is determined by integrating the temperature difference data. The current compensation value of a single MOSFET can be determined using the following formula during the integration calculation:

[0035]

[0036] Among them, I com K is the current compensation value. p T is the first preset scaling factor. i For the temperature control cycle, T diff (t) represents the temperature difference over time t, and c is a preset constant.

[0037] S104: According to the preset current control cycle, based on the current compensation value, the current data, and the preset current expectation value, output the duty cycle of the single MOS transistor.

[0038] After obtaining the current compensation value, if the current control cycle is reached, the duty cycle of a single MOSFET can be output based on the obtained current compensation value, current data, and preset current expectation value. Duty cycle refers to the proportion of on-time relative to the total time within a pulse cycle. For example, if a circuit is on for half of its operating cycle, its duty cycle is 50%. If the signal voltage applied to this component is 5V, then the actual average operating voltage or effective voltage value is 2.5V. Assuming this component is an electronic valve, when the circuit is fully on, the valve is fully open; when the duty cycle is 50%, the valve is half-open. Similarly, when the duty cycle is set to 20%, the valve opening should obviously be 20%. Thus, this valve can be arbitrarily adjusted within the range of 0% (fully closed) to 100% (fully open).

[0039] In one embodiment, when determining the duty cycle of a single MOSFET, firstly, based on current data, expected current value, and current compensation value, the current difference of the single MOSFET is determined. Then, the intermediate duty cycle of the single MOSFET is determined using the current difference. Finally, it is determined whether the intermediate duty cycle exceeds a preset value. If it does not exceed the preset value, the intermediate duty cycle is used as the duty cycle of the single MOSFET; otherwise, the preset value is used as the duty cycle of the single MOSFET. For example, if the calculated intermediate duty cycle is 80%, and the preset value is a minimum of 50% and a maximum of 70%, then 70% is selected as the duty cycle of the single MOSFET.

[0040] In one embodiment, the current difference can be determined by the following formula:

[0041] I diff =I ref -I real +I com

[0042] Among them, I diff I is the current difference. ref I is the desired value of the current. real This represents the actual current value corresponding to the current data.

[0043] Furthermore, the intermediate duty cycle can be obtained using the following formula:

[0044]

[0045] Where U(t) is the intermediate duty cycle, K m I is the second preset scaling factor. diff (t) is a function of the current difference with respect to time t, where T l For the current control cycle, I diff′ (t) is I diff The derivative of (t).

[0046] S105: Perform the switching action of the single MOS transistor according to the duty cycle.

[0047] After obtaining the duty cycle of each MOSFET, the switching action of individual MOSFETs can be executed according to the duty cycle. Thus, when the temperature of one MOSFET is too high, the current flowing through that MOSFET is reduced, while the current of the other MOSFETs is increased. This achieves the effect of reducing temperature without affecting the total current.

[0048] The aforementioned temperature control cycle and current control cycle can be pre-stored in the computer device's storage. When the MOSFET temperature needs to be adjusted, the computer device can select the temperature control cycle and current control cycle from the storage device. Alternatively, the computer device can obtain the temperature control cycle and current control cycle from other external devices. For example, the temperature control cycle and current control cycle can be stored in the cloud. When the MOSFET temperature needs to be adjusted, the computer device can obtain the temperature control cycle and current control cycle from the cloud. This embodiment does not limit the method of obtaining the temperature control cycle and current control cycle.

[0049] In one embodiment, since the temperature response speed is much slower than the current response speed, the cycle length corresponding to the temperature control cycle is shorter than the cycle length corresponding to the current control cycle. Therefore, if the current control cycle is reached before the temperature control cycle is reached, the current compensation value determined in the previous temperature control cycle is directly selected to calculate the duty cycle.

[0050] like Figure 3 As shown in the illustration, this application embodiment also provides a temperature control device for MOSFETs in a DC / DC converter, comprising: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to enable the at least one processor to: collect temperature data and current data of multiple MOSFETs in the DC / DC converter respectively; determine the temperature difference data between a single MOSFET and the average temperature of the multiple MOSFETs according to a preset temperature control cycle; determine the current compensation value of the single MOSFET based on the temperature difference data; output the duty cycle of the single MOSFET according to the current compensation value, the current data, and a preset current expectation value according to a preset current control cycle; and execute the switching action of the single MOSFET according to the duty cycle.

[0051] This application embodiment also provides a non-volatile computer storage medium storing computer-executable instructions, wherein the computer-executable instructions are configured to: collect temperature data and current data of multiple MOSFETs in a DC / DC converter respectively; determine the temperature difference data between a single MOSFET and the average temperature of the multiple MOSFETs according to a preset temperature control cycle; determine the current compensation value of the single MOSFET based on the temperature difference data; output the duty cycle of the single MOSFET according to the current compensation value, the current data, and a preset current expectation value according to a preset current control cycle; and execute the switching action of the single MOSFET according to the duty cycle.

[0052] The various embodiments in this application are described in a progressive manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, the device and medium embodiments are basically similar to the method embodiments, so the description is relatively simple; relevant parts can be referred to the description of the method embodiments.

[0053] The devices and media provided in this application are one-to-one with the methods. Therefore, the devices and media also have similar beneficial technical effects as their corresponding methods. Since the beneficial technical effects of the methods have been described in detail above, the beneficial technical effects of the devices and media will not be repeated here.

[0054] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0055] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0056] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0057] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0058] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0059] Memory may include non-persistent storage in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. Memory is an example of computer-readable media.

[0060] Computer-readable media includes both permanent and non-permanent, removable and non-removable media that can store information using any method or technology. Information can be computer-readable instructions, data structures, modules of programs, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic magnetic disk storage or other magnetic storage devices, or any other non-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include transient computer-readable media, such as modulated data signals and carrier waves.

[0061] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0062] The above description is merely an embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principle of this application should be included within the scope of the claims of this application.

Claims

1. A method for temperature control of a MOSFET in a DC / DC converter, characterized in that, include: Temperature and current data of multiple MOSFETs in the DC / DC converter were collected separately. According to a preset temperature control cycle, determine the temperature difference data between a single MOSFET and the average temperature of the multiple MOSFETs; Based on the temperature difference data, determine the current compensation value for the individual MOS transistor; According to the preset current control cycle, based on the current compensation value, the current data, and the preset current expectation value, the duty cycle of the single MOS transistor is output. The switching action of the single MOS transistor is executed according to the duty cycle; The step of determining the temperature difference data between a single MOSFET and the average temperature of the plurality of MOSFETs according to a preset temperature control cycle specifically includes: Based on the temperature data of the plurality of MOSFETs, determine the average temperature of the plurality of MOSFETs; Select any single MOSFET from the plurality of MOSFETs, and determine the intermediate temperature difference between the single MOSFET and the average temperature based on the temperature data of the single MOSFET. Determine whether the intermediate temperature difference data exceeds a preset temperature threshold. If it does, then use the intermediate temperature difference data as the temperature difference data. If the difference is not exceeded, the temperature difference data is considered to be non-existent. The step of outputting the duty cycle of a single MOSFET according to a preset current control cycle, based on the current compensation value, the current data, and a preset expected current value, specifically includes: The current difference of a single MOSFET is determined based on the current data, the expected current value, and the current compensation value. The intermediate duty cycle of the single MOS transistor is determined by the current difference. Determine whether the intermediate duty cycle exceeds a preset value. If it does not exceed the preset value, then use the intermediate duty cycle as the duty cycle of the single MOS transistor. If the value exceeds the preset ratio, the duty cycle of the single MOS transistor will be used. The duration of the temperature control cycle is shorter than the duration of the current control cycle.

2. The method according to claim 1, characterized in that, The step of determining the current compensation value of a single MOSFET based on the temperature difference data specifically includes: The current compensation value corresponding to the temperature difference data is determined by integrating the temperature difference data. The integral calculation specifically includes determining the current compensation value of a single MOSFET using the following formula: in, This is the current compensation value. The first preset proportional coefficient, For temperature control cycle, For temperature difference data with respect to time t, This is a preset constant.

3. The method according to claim 2, characterized in that, The step of determining the current difference of a single MOSFET based on the current data, the expected current value, and the current compensation value specifically includes: The current difference is determined using the following formula: in, This is the current difference. The desired current value, This represents the actual current value corresponding to the current data.

4. The method according to claim 3, characterized in that, Determining the intermediate duty cycle of a single MOSFET using the current difference specifically includes: The intermediate duty cycle is obtained using the following formula: in, This is the intermediate duty cycle. This is the second preset proportional coefficient. Let be a function of the current difference with respect to time t. For the current control cycle, for The derivative of .

5. The method according to claim 1, characterized in that, The acquisition of temperature data from multiple MOSFETs within the DC / DC converter specifically includes: Temperature data corresponding to each of the plurality of MOS transistors are obtained by using multiple temperature sensors respectively set on one side of the plurality of MOS transistors.

6. A temperature control device for a MOSFET in a DC / DC converter, characterized in that, include: At least one processor; And, a memory communicatively connected to the at least one processor; wherein, The memory stores instructions executable by the at least one processor, which, when executed by the at least one processor, enables the at least one processor to perform the steps of the method as claimed in any one of claims 1-5.

7. A non-volatile computer storage medium storing computer-executable instructions, characterized in that, The computer-executable instructions are configured to perform the steps of the method as claimed in any one of claims 1-5.

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