Over-temperature protection device for power field effect transistor, electric vehicle controller and electric vehicle

Abstract

The utility model discloses power field effect tube's over temperature protection equipment, electric motor car controller and electric motor car relates to circuit control technical field, and this over temperature protection equipment includes three phase field effect tube temperature detection module, temperature protection reference voltage module, temperature comparison module and power supply control module, temperature comparison module is in response to three phase field effect tube temperature detection module detection field effect tube temperature level and temperature protection reference voltage module provides temperature protection level, and the power supply control signal of output, power supply control module is in response to power supply control signal, and the field effect tube drive level for adjusting the working condition of field effect tube driver is outputted. The utility model discloses through the mode control of voltage comparison power supply control module opens or stops to field effect tube driver and provides electric energy, changes the working condition of field effect tube driver, and then opens or stops the work of power field effect tube, to protect power field effect tube.

Description

Technical Field

[0001] This utility model relates to the field of circuit control technology, and in particular to over-temperature protection devices for power MOSFETs, electric vehicle controllers, and electric vehicles. Background Technology

[0002] Currently, the over-temperature protection method for power MOSFETs involves detecting the temperature value at a specific location within the power MOSFET module. When the detected temperature value at that location exceeds the pre-set temperature range, the operation of the power MOSFET module is stopped via software control to prevent damage to the power devices within the module.

[0003] However, software-controlled shutdown of power MOSFET modules has limited real-time performance and poor over-temperature protection when dealing with sudden temperature changes. Therefore, this paper proposes a hardware over-temperature protection circuit for power MOSFETs. Based on the real-time temperature of the power MOSFET module, the circuit promptly switches on or off the power supply to the module, ensuring it remains in a stable and safe state. This is one of the most pressing problems to be solved in the field of circuit control. Utility Model Content

[0004] This invention provides an over-temperature protection device for power MOSFETs, an electric vehicle controller, and an electric vehicle. It controls the power supply control module to turn on or off to supply power to the power MOSFET module by voltage comparison. It protects the power MOSFET in the power MOSFET module with hardware circuitry and can cope with the condition of instantaneous temperature changes. It does not require software to process temperature data or control the power MOSFET module. The over-temperature protection device has low design and use costs and high response speed and real-time performance.

[0005] According to one aspect of the present invention, an over-temperature protection device for a power MOSFET is provided. The over-temperature protection device includes: a three-phase MOSFET temperature detection module, a temperature protection reference voltage module, a temperature comparison module, and a power supply control module. The temperature comparison module is connected to the three-phase MOSFET temperature detection module, the temperature protection reference voltage module, and the power supply control module, respectively. The power supply control module is connected to the power MOSFET module. The power MOSFET module includes a MOSFET driver and a power MOSFET.

[0006] The temperature comparison module responds to the field-effect transistor temperature level detected by the three-phase field-effect transistor temperature detection module and the temperature protection level provided by the temperature protection reference voltage module, and outputs a power supply control signal; the power supply control module responds to the power supply control signal and outputs a field-effect transistor drive level; the field-effect transistor drive level is used to adjust the operating state of the field-effect transistor driver to protect the power field-effect transistor.

[0007] Optionally, the three-phase MOSFET temperature detection module includes an A-phase MOSFET temperature detection unit, a B-phase MOSFET temperature detection unit, and a C-phase MOSFET temperature detection unit. The A-phase MOSFET temperature detection unit is used to detect the real-time temperature of the A-phase power MOSFET of the power MOSFET module and convert the detected real-time temperature into an A-phase temperature level. The B-phase MOSFET temperature detection unit is used to detect the real-time temperature of the B-phase power MOSFET of the power MOSFET module and convert the detected real-time temperature into a B-phase temperature level. The C-phase MOSFET temperature detection unit is used to detect the real-time temperature of the C-phase power MOSFET of the power MOSFET module and convert the detected real-time temperature into a C-phase temperature level.

[0008] Optionally, the A-phase MOSFET temperature detection unit includes an A-phase temperature acquisition resistor, a first resistor, a second resistor, and a first capacitor; the B-phase MOSFET temperature detection unit includes a B-phase temperature acquisition resistor, a third resistor, a fourth resistor, and a second capacitor; and the C-phase MOSFET temperature detection unit includes a C-phase temperature acquisition resistor, a fifth resistor, a sixth resistor, and a third capacitor. The relative distance between the A-phase temperature acquisition resistor and the A-phase power MOSFET is less than a temperature detection distance threshold; the relative distance between the B-phase temperature acquisition resistor and the B-phase power MOSFET is less than a temperature detection distance threshold; and the relative distance between the C-phase temperature acquisition resistor and the C-phase power MOSFET is less than a temperature detection distance threshold.

[0009] Optionally, the first end of the phase A temperature acquisition resistor is connected to the first end of the first resistor and the first end of the second resistor, the second end of the phase A temperature acquisition resistor is connected to the first end of the first capacitor and the ground signal, the second end of the first resistor is connected to the first electrical signal, and the second end of the second resistor is connected to the second end of the first capacitor and the temperature comparison module; the first end of the phase B temperature acquisition resistor is connected to the first end of the third resistor and the first end of the fourth resistor, the second end of the phase B temperature acquisition resistor is connected to the first end of the second capacitor and the ground signal, the second end of the third resistor is connected to the first electrical signal, and the second end of the fourth resistor is connected to the second end of the second capacitor and the temperature comparison module; the first end of the phase C temperature acquisition resistor is connected to the first end of the fifth resistor and the first end of the sixth resistor, the second end of the phase C temperature acquisition resistor is connected to the first end of the third capacitor and the ground signal, the second end of the fifth resistor is connected to the first electrical signal, and the second end of the sixth resistor is connected to the second end of the third capacitor and the temperature comparison module.

[0010] Optionally, the temperature protection reference voltage module includes a fourth capacitor, a seventh resistor, and an eighth resistor; wherein, the first terminal of the fourth capacitor is connected to the first terminal of the seventh resistor, the first terminal of the eighth resistor, and the temperature comparison module, the second terminal of the fourth capacitor is connected to the second terminal of the eighth resistor and the ground signal, and the second terminal of the seventh resistor is connected to the first electrical signal.

[0011] Optionally, the temperature comparison module includes an A-phase temperature comparison unit, a B-phase temperature comparison unit, a C-phase temperature comparison unit, and a control signal determination unit. The A-phase temperature comparison unit responds to the A-phase temperature level output by the A-phase field-effect transistor temperature detection unit and the temperature protection level provided by the temperature protection reference voltage module, and outputs an A-phase control signal. The B-phase temperature comparison unit responds to the B-phase temperature level output by the B-phase field-effect transistor temperature detection unit and the temperature protection level provided by the temperature protection reference voltage module, and outputs a B-phase control signal. The C-phase temperature comparison unit responds to the C-phase temperature level output by the C-phase field-effect transistor temperature detection unit and the temperature protection level provided by the temperature protection reference voltage module, and outputs a C-phase control signal. The control signal determination unit responds to the A-phase control signal, the B-phase control signal, and the C-phase control signal, and outputs a power supply control signal.

[0012] Optionally, the A-phase temperature comparison unit includes a ninth resistor, a fifth capacitor, a sixth capacitor, a first diode, and an A-phase comparator; the B-phase temperature comparison unit includes a tenth resistor, a seventh capacitor, an eighth capacitor, a second diode, and a B-phase comparator; the C-phase temperature comparison unit includes an eleventh resistor, a ninth capacitor, a tenth capacitor, a third diode, and a C-phase comparator; and the control signal determination unit includes a twelfth resistor, a thirteenth resistor, and an eleventh capacitor.

[0013] Optionally, the positive input of phase A comparator is connected to the temperature protection reference voltage module; the negative input of phase A comparator is connected to the first terminal of the ninth resistor and the first terminal of the fifth capacitor, respectively; the second terminal of the fifth capacitor is connected to ground; the second terminal of the ninth resistor is connected to the temperature detection unit of phase A MOSFET; the ground terminal of phase A comparator is connected to ground; the power supply terminal of phase A comparator is connected to the first terminal of the sixth capacitor and the first electrical signal, respectively; the second terminal of the sixth capacitor is connected to ground; the output terminal of phase A comparator is connected to the first terminal of the first diode, and the second terminal of the first diode is connected to the second terminal of the second diode, the second terminal of the third diode, the first terminal of the twelfth resistor, and the first terminal of the thirteenth resistor, respectively. Similarly, the positive input of phase B comparator is connected to the temperature protection reference voltage module; the negative input of phase B comparator is connected to the first terminal of the tenth resistor and the first terminal of the seventh capacitor, respectively; the second terminal of the seventh capacitor is connected to ground; and the second terminal of the tenth resistor is connected to the temperature detection unit of phase B MOSFET. In the measurement unit, the ground terminal of phase B comparator is connected to ground signal, the power supply terminal of phase B comparator is connected to the first terminal of the eighth capacitor and the first electrical signal respectively, the second terminal of the eighth capacitor is connected to ground signal, and the output terminal of phase B comparator is connected to the first terminal of the second diode; the positive input terminal of phase C comparator is connected to the temperature protection reference voltage module, the inverting input terminal of phase C comparator is connected to the first terminal of the eleventh resistor and the first terminal of the ninth capacitor respectively, the second terminal of the ninth capacitor is connected to ground signal, the second terminal of the eleventh resistor is connected to the C-phase MOSFET temperature detection unit, the ground terminal of phase C comparator is connected to ground signal, the power supply terminal of phase C comparator is connected to the first terminal of the tenth capacitor and the first electrical signal respectively, the second terminal of the tenth capacitor is connected to ground signal, and the output terminal of phase C comparator is connected to the first terminal of the third diode; the second terminal of the twelfth resistor is connected to the first electrical signal, the second terminal of the thirteenth resistor is connected to the first terminal of the eleventh capacitor and the power supply control module respectively, and the second terminal of the eleventh capacitor is connected to ground signal.

[0014] Optionally, the power supply control module includes a fourteenth resistor, a fifteenth resistor, a sixteenth resistor, a seventeenth resistor, a twelfth capacitor, a transistor, and a field-effect transistor. The first terminal of the fourteenth resistor is connected to the temperature comparison module. The second terminal of the fourteenth resistor is connected to the first terminal of the fifteenth resistor, the first terminal of the twelfth capacitor, and the first terminal of the transistor. The second terminal of the fifteenth resistor is connected to the second terminal of the twelfth capacitor, the second terminal of the transistor, and ground. The third terminal of the transistor is connected to the first terminal of the sixteenth resistor. The second terminal of the sixteenth resistor is connected to the first terminal of the seventeenth resistor and the second terminal of the field-effect transistor. The second terminal of the seventeenth resistor is connected to the first terminal of the field-effect transistor and a second electrical signal. The third terminal of the field-effect transistor is connected to the power field-effect transistor module.

[0015] According to another aspect of the present invention, an electric vehicle controller is provided, which includes: a power MOSFET module and an over-temperature protection device for any one of the power MOSFETs in the embodiments of the present invention.

[0016] According to another aspect of the present invention, an electric vehicle is provided, which includes any one of the electric vehicle controllers in the embodiments of the present invention.

[0017] Among them, electric vehicles are either electric two-wheeled vehicles or electric three-wheeled vehicles.

[0018] The over-temperature protection device for power MOSFETs of this invention includes: a three-phase MOSFET temperature detection module, a temperature protection reference voltage module, a temperature comparison module, and a power supply control module. The temperature comparison module is connected to the three-phase MOSFET temperature detection module, the temperature protection reference voltage module, and the power supply control module, respectively. The relative distance between the three-phase MOSFET temperature detection module and the power MOSFET module is less than a temperature detection distance threshold. The temperature comparison module, in response to the MOSFET temperature level detected by the three-phase MOSFET temperature detection module and the temperature protection level provided by the temperature protection reference voltage module, outputs a power supply control signal. The power supply control module, in response to the power supply control signal, outputs a MOSFET drive level. The MOSFET drive level is used to adjust the operating state of the MOSFET driver to protect the power MOSFET. This utility model's over-temperature protection device uses a three-phase MOSFET temperature detection module to collect real-time temperature information from the power MOSFET module. A temperature comparison module compares the voltage level corresponding to the temperature information detected by the three-phase MOSFET temperature detection module with the temperature protection level provided by the temperature protection reference voltage module. The power supply control module turns on or off the power MOSFET module based on the comparison result. By using hardware circuitry to protect the power MOSFETs in the power MOSFET module, it eliminates the need for software processing of temperature data and control of the power MOSFET module. This results in low design and usage costs, high response speed and real-time performance, and the ability to handle conditions with instantaneous temperature changes, making it highly practical.

[0019] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of this utility model, nor is it intended to limit the scope of this utility model. Other features of this utility model will become readily apparent from the following description. Attached Figure Description

[0020] To more clearly illustrate the technical solutions of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the structure of an over-temperature protection device for a power MOSFET provided by this utility model;

[0022] Figure 2 This is a structural schematic diagram of a power MOSFET module provided by this utility model;

[0023] Figure 3 This is a schematic diagram of the structure and connection method of a three-phase field-effect transistor temperature detection module provided by this utility model;

[0024] Figure 4 This is a schematic diagram of the structure and connection method of a temperature protection reference voltage module provided by this utility model;

[0025] Figure 5 This is a schematic diagram of the structure and connection method of a temperature comparison module provided by this utility model;

[0026] Figure 6 This is a schematic diagram of the structure and connection method of a power supply control module provided by this utility model.

[0027] Figure label:

[0028] 1-Three-phase MOSFET temperature detection module, 11-A-phase MOSFET temperature detection unit, 12-B-phase MOSFET temperature detection unit, 13-C-phase MOSFET temperature detection unit, 2-Temperature protection reference voltage module, 3-Temperature comparison module, 31-A-phase temperature comparison unit, 32-B-phase temperature comparison unit, 33-C-phase temperature comparison unit, 34-Control signal determination unit, 4-Power supply control module. Detailed Implementation

[0029] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0030] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this utility model are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the utility model described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0031] Software-based over-temperature protection for power MOSFET modules typically requires sampling the temperature of multiple power devices within the module, calculating the average of the sampled temperature values, and initiating an over-temperature protection process when the average temperature exceeds the protection limit. This method involves acquiring and processing temperature data, generating control commands for the power MOSFET module, and controlling its operation. It has low real-time performance, places certain demands on computing resources, and results in high protection costs for the power MOSFET module.

[0032] Figure 1 This is a schematic diagram of an over-temperature protection device for power MOSFETs provided by this utility model. This embodiment is applicable to low-cost, high-efficiency over-temperature protection of power MOSFET modules. (Refer to...) Figure 1 The over-temperature protection device specifically includes: a three-phase MOSFET temperature detection module 1, a temperature protection reference voltage module 2, a temperature comparison module 3, and a power supply control module 4. The temperature comparison module 3 is connected to the three-phase MOSFET temperature detection module 1, the temperature protection reference voltage module 2, and the power supply control module 4, respectively. The power supply control module 4 is connected to the power MOSFET module, which includes a MOSFET driver and a power MOSFET.

[0033] The temperature comparison module responds to the field-effect transistor temperature level detected by the three-phase field-effect transistor temperature detection module and the temperature protection level provided by the temperature protection reference voltage module, and outputs a power supply control signal; the power supply control module responds to the power supply control signal and outputs a field-effect transistor drive level; the field-effect transistor drive level is used to adjust the operating state of the field-effect transistor driver to protect the power field-effect transistor.

[0034] The three-phase MOSFET temperature detection module uses a negative temperature coefficient (NTC) thermistor deployed or placed near the power MOSFET to detect the temperature of the metal-oxide-semiconductor (MOS) drive circuit within the MOSFET. Since the NTC thermistor can only detect the temperature of devices within a certain distance (the specific distance depends on the NTC thermistor's performance parameters), the relative distance between the NTC thermistor in the three-phase MOSFET temperature detection module and the power devices (i.e., the power MOSFETs) in the power MOSFET module needs to be less than the temperature detection distance threshold (i.e., the maximum sampling distance of the NTC thermistor) to ensure that the NTC thermistor can acquire the real-time temperature of the power devices. The three-phase MOSFET temperature detection module can acquire the real-time temperature of the power devices in the power MOSFET module and convert it into a voltage signal, i.e., the MOSFET temperature level. The temperature protection reference voltage module provides a temperature protection level through resistor voltage division. The temperature protection level is used to determine whether the temperature value corresponding to the MOSFET temperature level is over-temperature. The temperature comparison module uses the MOSFET temperature level detected by the three-phase MOSFET temperature detection module as the inverting input of the comparator, and the temperature protection level provided by the temperature protection reference voltage module as the positive input of the comparator. When the MOSFET temperature level is higher than the temperature protection level, the comparator outputs a low level; conversely, when the MOSFET temperature level is not higher than the temperature protection level, the comparator outputs a high level. The comparator's output level is the power supply control signal. This signal can change the output signal (MOSFET drive level) of the power supply control module, thereby changing the operating state of the MOSFET driver (operating when receiving a high level and not operating when receiving a low level) to protect the power MOSFET. For example, when the comparator outputs a high level, the drive circuit in the power supply control module is normally conducting, allowing the power supply control module to supply power to the power MOSFET module, which operates normally. When the comparator outputs a low level, the power supply circuit in the power supply control module is disconnected, preventing the power supply control module from supplying power to the power MOSFET module, which then stops operating. Essentially, this stops supplying power to the MOSFET driver, thus stopping the power MOSFET's operation.

[0035] Figure 2 This is a structural schematic diagram of a power MOSFET module provided by this utility model. Figure 2As can be seen, the power MOSFET module includes three-phase power MOSFETs. The MOS drive circuits are: an A-phase MOSFET driver (which can be understood as a driver chip) and an A-phase power MOSFET forming an A-phase MOS drive circuit; a B-phase MOSFET driver and a B-phase power MOSFET forming a B-phase MOS drive circuit; and a C-phase MOSFET driver and a C-phase power MOSFET forming a C-phase MOS drive circuit. All three-phase MOSFET drivers are connected to the power supply control module, and their operating state is controlled by the output level of the power supply control module. The power MOSFETs include a first MOSFET and a second MOSFET. The first MOSFET is connected to an electrical signal, and the second MOSFET is grounded. Generally, the temperature of the second MOSFET is higher than that of the first MOSFET. Therefore, this invention detects the temperature of the second power MOSFET in the three-phase power MOSFET module.

[0036] Figure 3 This is a schematic diagram illustrating the structure and connection method of a three-phase field-effect transistor temperature detection module provided by this utility model. Figure 3 VCC1 represents the first electrical signal, which is 3.3V in this invention. GND represents the ground signal. The port numbers of each component are... Figure 3 It is not shown in the text. From Figure 3 As can be seen from the diagram, the three-phase field-effect transistor temperature detection module 1 includes an A-phase field-effect transistor temperature detection unit 11, a B-phase field-effect transistor temperature detection unit 12, and a C-phase field-effect transistor temperature detection unit 13.

[0037] This invention utilizes a three-channel NTC thermistor circuit (i.e., a three-phase MOSFET temperature detection unit) to detect the temperature of different MOS drive circuits in a power MOSFET module. The NTC thermistor circuit converts the detected temperature value into a level signal for output. Specifically, the A-phase MOSFET temperature detection unit detects the real-time temperature of the first power MOSFET in phase A of the power MOSFET module and converts the detected real-time temperature into an A-phase temperature level; the B-phase MOSFET temperature detection unit detects the real-time temperature of the first power MOSFET in phase B of the power MOSFET module and converts the detected real-time temperature into a B-phase temperature level; and the C-phase MOSFET temperature detection unit detects the real-time temperature of the first power MOSFET in phase C of the power MOSFET module and converts the detected real-time temperature into a C-phase temperature level.

[0038] Combination Figure 3The A-phase field-effect transistor temperature detection unit 11 includes an A-phase temperature acquisition resistor RA, a first resistor R1, a second resistor R2, and a first capacitor C1. The B-phase field-effect transistor temperature detection unit 12 includes a B-phase temperature acquisition resistor RB, a third resistor R3, a fourth resistor R4, and a second capacitor C2. The C-phase field-effect transistor temperature detection unit 13 includes a C-phase temperature acquisition resistor RC, a fifth resistor R5, a sixth resistor R6, and a third capacitor C3.

[0039] In this configuration, the relative distance between the temperature acquisition resistor in phase A and the first power MOSFET in phase A is less than a temperature detection distance threshold; the relative distance between the temperature acquisition resistor in phase B and the first power MOSFET in phase B is less than a temperature detection distance threshold; and the relative distance between the temperature acquisition resistor in phase C and the first power MOSFET in phase C is less than a temperature detection distance threshold. This arrangement ensures that each temperature acquisition resistor can stably acquire the real-time temperature of its corresponding power MOSFET. Furthermore, the temperature acquisition resistor can also be deployed between the first and second power MOSFETs to simultaneously detect their temperatures; this invention does not limit this specific arrangement.

[0040] Specifically, the first end of the phase A temperature acquisition resistor is connected to the first end of the first resistor and the first end of the second resistor. The second end of the phase A temperature acquisition resistor is connected to the first end of the first capacitor and the ground signal. The second end of the first resistor is connected to the first electrical signal. The second end of the second resistor is connected to the second end of the first capacitor and the temperature comparison module. The first end of the phase B temperature acquisition resistor is connected to the first end of the third resistor and the first end of the fourth resistor. The second end of the phase B temperature acquisition resistor is connected to the first end of the second capacitor and the ground signal. The second end of the third resistor is connected to the first electrical signal. The second end of the fourth resistor is connected to the second end of the second capacitor and the temperature comparison module. The first end of the phase C temperature acquisition resistor is connected to the first end of the fifth resistor and the first end of the sixth resistor. The second end of the phase C temperature acquisition resistor is connected to the first end of the third capacitor and the ground signal. The second end of the fifth resistor is connected to the first electrical signal. The second end of the sixth resistor is connected to the second end of the third capacitor and the temperature comparison module.

[0041] The first, second, and third capacitors are filter capacitors used to filter out high-frequency noise and improve the accuracy of temperature detection. The three-phase temperature acquisition resistors are used to acquire the real-time temperature of the three-phase power MOSFETs. The A-phase temperature acquisition resistor can detect the MOS temperature of the A-phase power MOSFET by voltage division with the first resistor; the B-phase temperature acquisition resistor can detect the MOS temperature of the B-phase power MOSFET by voltage division with the third resistor; and the C-phase temperature acquisition resistor can detect the MOS temperature of the C-phase power MOSFET by voltage division with the fifth resistor. The outputs of the three-phase MOSFET temperature detection units serve as the inputs of the temperature comparison module. The output signal of the A-phase MOSFET temperature detection unit serves as the input signal of the A-phase temperature comparison unit; the output signal of the B-phase MOSFET temperature detection unit serves as the input signal of the B-phase temperature comparison unit; and the output signal of the C-phase MOSFET temperature detection unit serves as the input signal of the C-phase temperature comparison unit.

[0042] Figure 4 This is a schematic diagram illustrating the structure and connection method of a temperature protection reference voltage module provided by this utility model. Figure 4 In this context, VCC1 represents the first electrical signal, GND represents the ground signal, and the port numbers of each component are... Figure 4 It is not shown in the text. From Figure 4 As can be seen from the diagram, the temperature protection reference voltage module 2 includes a fourth capacitor C4, a seventh resistor R7, and an eighth resistor R8; the first end of the fourth capacitor C4 is connected to the first end of the seventh resistor R7, the first end of the eighth resistor R8, and the temperature comparison module 3, respectively; the second end of the fourth capacitor C4 is connected to the second end of the eighth resistor R8 and the ground signal, respectively; and the second end of the seventh resistor R7 is connected to the first electrical signal.

[0043] Specifically, the fourth capacitor is a filter capacitor used to filter out high-frequency noise and improve signal accuracy. The temperature protection level can be calculated based on the temperature protection threshold. The seventh and eighth resistors are high-precision resistors designed to provide the temperature protection level by voltage division.

[0044] Figure 5 This is a schematic diagram illustrating the structure and connection method of a temperature comparison module provided by this utility model. Figure 5 In this context, VCC1 represents the first electrical signal, GND represents the ground signal, and the port numbers of each component are... Figure 5 It is not shown in the text. From Figure 5 As can be seen from the diagram, the temperature comparison module 3 includes an A-phase temperature comparison unit 31, a B-phase temperature comparison unit 32, a C-phase temperature comparison unit 33, and a control signal determination unit 34.

[0045] The A-phase temperature comparison unit responds to the A-phase temperature level output by the A-phase field-effect transistor temperature detection unit and the temperature protection level provided by the temperature protection reference voltage module, and outputs an A-phase control signal. When the A-phase temperature level is not higher than the temperature protection level, the A-phase control signal is high; when the A-phase temperature level is higher than the temperature protection level, the A-phase control signal is low. The B-phase temperature comparison unit responds to the B-phase temperature level output by the B-phase field-effect transistor temperature detection unit and the temperature protection level provided by the temperature protection reference voltage module, and outputs a B-phase control signal. When the B-phase temperature level is not higher than the temperature protection level, the B-phase control signal is high; when the B-phase temperature level is higher than the temperature protection level, the B-phase control signal is low. The C-phase temperature comparison unit responds to the C-phase temperature level output by the C-phase MOSFET temperature detection unit and the temperature protection level provided by the temperature protection reference voltage module, outputting a C-phase control signal. When the C-phase temperature level is not higher than the temperature protection level, the C-phase control signal is high; when the C-phase temperature level is higher than the temperature protection level, the C-phase control signal is low. The control signal determination unit responds to the A-phase, B-phase, and C-phase control signals, outputting a power supply control signal. When all three control signals are high, the power supply control signal is high; when any of these signals is low, the power supply control signal is low. This configuration is designed to achieve over-temperature protection triggering based on the highest MOS circuit temperature.

[0046] Combination Figure 5 The A-phase temperature comparison unit 31 includes a ninth resistor R9, a fifth capacitor C5, a sixth capacitor C6, a first diode D1, and an A-phase comparator (CMP) CMP-A. The B-phase temperature comparison unit includes a tenth resistor R10, a seventh capacitor C7, an eighth capacitor C8, a second diode D2, and a B-phase comparator CMP-B. The C-phase temperature comparison unit includes an eleventh resistor R11, a ninth capacitor C9, a tenth capacitor C10, a third diode D3, and a C-phase comparator CMP-C. The control signal determination unit includes a twelfth resistor R12, a thirteenth resistor R13, and an eleventh capacitor C11. In the comparators, "+" indicates the positive input terminal, "-" indicates the inverting input terminal, "OUT" indicates the output terminal, "VCC" indicates the power supply terminal, and "GND" indicates the ground terminal.

[0047] The positive input of comparator A is connected to the temperature protection reference voltage module. The inverting input of comparator A is connected to the first terminal of the ninth resistor and the first terminal of the fifth capacitor, respectively. The second terminal of the fifth capacitor is connected to ground. The second terminal of the ninth resistor is connected to the A-phase MOSFET temperature detection unit. The ground terminal of comparator A is connected to ground. The power supply terminal of comparator A is connected to the first terminal of the sixth capacitor and the first electrical signal, respectively. The second terminal of the sixth capacitor is connected to ground. The output of comparator A is connected to the first terminal of the first diode. The second terminal of the first diode is connected to the second terminals of the second and third diodes, the first terminal of the twelfth resistor, and the first terminal of the thirteenth resistor, respectively. The positive input of comparator B is connected to the temperature protection reference voltage module. The inverting input of comparator B is connected to the first terminal of the tenth resistor and the first terminal of the seventh capacitor, respectively. The second terminal of the seventh capacitor is connected to ground. The second terminal of the tenth resistor is connected to the B-phase MOSFET temperature detection unit. The B-phase comparator's ground terminal is connected to ground. The B-phase comparator's power supply terminal is connected to the first terminal of the eighth capacitor and the first electrical signal, respectively. The second terminal of the eighth capacitor is connected to ground. The B-phase comparator's output terminal is connected to the first terminal of the second diode. The C-phase comparator's positive input terminal is connected to the temperature protection reference voltage module. The C-phase comparator's inverting input terminal is connected to the first terminal of the eleventh resistor and the first terminal of the ninth capacitor, respectively. The second terminal of the ninth capacitor is connected to ground. The second terminal of the eleventh resistor is connected to the C-phase MOSFET temperature detection unit. The C-phase comparator's ground terminal is connected to ground. The C-phase comparator's power supply terminal is connected to the first terminal of the tenth capacitor and the first electrical signal, respectively. The second terminal of the tenth capacitor is connected to ground. The C-phase comparator's output terminal is connected to the first terminal of the third diode. The second terminal of the twelfth resistor is connected to the first electrical signal. The second terminal of the thirteenth resistor is connected to the first terminal of the eleventh capacitor and the power supply control module, respectively. The second terminal of the eleventh capacitor is connected to ground.

[0048] Among them, the first diode, the second diode, and the third diode serve as anti-reverse diodes, aiming to prevent the output information of the comparator from being affected by the output information of other comparators; the ninth resistor and the fifth capacitor serve as filters in the A-phase temperature comparator unit, the tenth resistor and the seventh capacitor serve as filters in the B-phase temperature comparator unit, and the eleventh resistor and the ninth capacitor serve as filters in the C-phase temperature comparator unit.

[0049] Figure 6 This is a schematic diagram illustrating the structure and connection method of a power supply control module provided by this utility model. Figure 6 VCC2 represents the second electrical signal, which is 15V in this invention. GND represents the ground signal. The port numbers of each component are... Figure 6 It is not shown in the text. From Figure 6As can be seen from the diagram, the power supply control module 4 includes the fourteenth resistor R14, the fifteenth resistor R15, the sixteenth resistor R16, the seventeenth resistor R17, the twelfth capacitor C12, the transistor Q, and the field-effect transistor.

[0050] The first end of the fourteenth resistor is connected to the temperature comparison module, which is essentially connected to the control signal determination unit of the temperature comparison module. The second end of the fourteenth resistor is connected to the first end of the fifteenth resistor, the first end of the twelfth capacitor, and the first end of the transistor. The second end of the fifteenth resistor is connected to the second end of the twelfth capacitor, the second end of the transistor, and the ground signal. The third end of the transistor is connected to the first end of the sixteenth resistor. The second end of the sixteenth resistor is connected to the first end of the seventeenth resistor and the second end of the field-effect transistor. The second end of the seventeenth resistor is connected to the first end of the field-effect transistor and the second electrical signal. The third end of the field-effect transistor is connected to the power field-effect transistor module.

[0051] Among them, the fourteenth resistor is a current-limiting resistor, which can control the current supplied to the base of the transistor; the fifteenth resistor is a pull-down resistor, which can prevent the transistor from being falsely turned on, and can also ensure that the base voltage is greater than its turn-on voltage during normal circuit operation; the twelfth capacitor is a filter capacitor, and the MOSFET is a switching device; the sixteenth resistor is a current-limiting resistor, which can control the current flowing to the gate of the MOSFET; and the seventeenth resistor is a pull-up resistor, which can provide a bias voltage to prevent the MOSFET from being falsely turned on.

[0052] Specifically, when the control signal determination unit outputs a high level, the transistor turns on, pulling down the gate voltage of the field-effect transistor (FET), thus turning on the FET. At this time, the second electrical signal can supply power to the power FET module, enabling it to operate. When the control signal determination unit outputs a low level, the transistor turns off, there is no voltage drop between the gate and source of the FET, the FET does not conduct, the second electrical signal cannot supply power to the power FET module, and the power FET module does not operate. Figure 6 As can be seen, the power supply signals of the three-phase power MOSFETs are the same. In the method of over-temperature protection based on the highest MOS temperature, if the temperature of one power MOSFET is too high, the power supply to the three power MOSFETs will stop.

[0053] This invention relates to an over-temperature protection device. A three-phase MOSFET temperature detection module collects real-time temperature information from the power MOSFET module. A temperature comparison module compares the voltage levels corresponding to the detected temperatures with the temperature protection reference voltage provided by the temperature protection module. The power supply control module then turns the power supply to the power MOSFET module on or off based on the comparison result. This hardware-based protection eliminates the need for software processing of temperature data and control of the power MOSFET module, resulting in low design and operating costs, high response speed and real-time performance, and the ability to handle sudden temperature changes, making it highly practical. Furthermore, this over-temperature protection device can simultaneously detect the temperatures of the three MOS circuits (power MOSFETs) within the power MOSFET module. The temperature comparison module then triggers over-temperature protection based on the highest MOS circuit temperature. Specifically, during normal operation, the power supply control module supplies power to the power MOSFET module in a normally conducting manner. When the highest MOS circuit temperature exceeds the temperature threshold (the temperature value corresponding to the temperature protection level), the power supply control module stops supplying power to the power MOSFET module, thus achieving over-temperature protection. Furthermore, in the face of a sudden temperature rise in the MOS circuit of the power MOSFET module, the over-temperature protection device of this invention can also quickly stop supplying power to the power MOSFET module, thereby protecting the power MOSFET module under extreme conditions (sudden temperature change).

[0054] This utility model also provides an electric vehicle controller, which includes: a power MOSFET module and an over-temperature protection device for any one of the power MOSFETs in the above embodiments.

[0055] The electric vehicle controller in the above embodiments includes an over-temperature protection device for any one of the power MOSFETs in the above embodiments. The over-temperature protection device monitors the temperature of the power MOSFET in real time, and when the temperature of the power MOSFET exceeds the temperature at which it can operate stably (the voltage corresponding to the temperature detected by the three-phase MOSFET temperature detection module is higher than the reference voltage provided by the temperature protection reference voltage module, which is the voltage corresponding to the highest temperature at which the power MOSFET can operate stably), it stops supplying power to the power MOSFET module, terminating the current operation of the power MOSFET module, thereby protecting the power devices (i.e., the power MOSFETs) of the power MOSFET module. Furthermore, the electric vehicle controller provided by this utility model includes the over-temperature protection device for the power MOSFET in the above embodiments, possessing the corresponding beneficial effects of the aforementioned over-temperature protection device for power MOSFETs.

[0056] Secondly, this utility model also provides an electric vehicle, which can be an electric two-wheeler or an electric three-wheeler. The electric vehicle of this utility model includes the electric vehicle controller in the above embodiments and has the corresponding beneficial effects of the electric vehicle controller.

[0057] It should be understood that the various forms of the process shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this utility model can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this utility model can be achieved, and this is not limited herein.

[0058] The specific embodiments described above do not constitute a limitation on the scope of protection of this utility model. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the scope of protection of this utility model.

Claims

1. An over-temperature protection device for a power MOSFET, characterized in that, include: The system comprises a three-phase MOSFET temperature detection module, a temperature protection reference voltage module, a temperature comparison module, and a power supply control module. The temperature comparison module is connected to the three-phase MOSFET temperature detection module, the temperature protection reference voltage module, and the power supply control module. The power supply control module is connected to a power MOSFET module, which includes a MOSFET driver and a power MOSFET. The temperature comparison module responds to the field-effect transistor temperature level detected by the three-phase field-effect transistor temperature detection module and the temperature protection level provided by the temperature protection reference voltage module, and outputs a power supply control signal; the power supply control module responds to the power supply control signal and outputs a field-effect transistor drive level; the field-effect transistor drive level is used to adjust the operating state of the field-effect transistor driver to protect the power field-effect transistor.

2. The over-temperature protection device according to claim 1, characterized in that, The three-phase field-effect transistor temperature detection module includes an A-phase field-effect transistor temperature detection unit, a B-phase field-effect transistor temperature detection unit, and a C-phase field-effect transistor temperature detection unit. The A-phase field-effect transistor temperature detection unit is used to detect the real-time temperature of the A-phase power field-effect transistor of the power field-effect transistor module and convert the detected real-time temperature into the A-phase temperature level. The B-phase field-effect transistor temperature detection unit is used to detect the real-time temperature of the B-phase power field-effect transistor of the power field-effect transistor module and convert the detected real-time temperature into the B-phase temperature level. The C-phase field-effect transistor temperature detection unit is used to detect the real-time temperature of the C-phase power field-effect transistor of the power field-effect transistor module and convert the detected real-time temperature into the C-phase temperature level.

3. The over-temperature protection device according to claim 2, characterized in that, The A-phase field-effect transistor temperature detection unit includes an A-phase temperature acquisition resistor, a first resistor, a second resistor, and a first capacitor; the B-phase field-effect transistor temperature detection unit includes a B-phase temperature acquisition resistor, a third resistor, a fourth resistor, and a second capacitor; and the C-phase field-effect transistor temperature detection unit includes a C-phase temperature acquisition resistor, a fifth resistor, a sixth resistor, and a third capacitor. Wherein, the relative distance between the temperature acquisition resistor of phase A and the power MOSFET of phase A is less than the temperature detection distance threshold, the relative distance between the temperature acquisition resistor of phase B and the power MOSFET of phase B is less than the temperature detection distance threshold, and the relative distance between the temperature acquisition resistor of phase C and the power MOSFET of phase C is less than the temperature detection distance threshold.

4. The over-temperature protection device according to claim 3, characterized in that, The first end of the phase A temperature acquisition resistor is connected to the first end of the first resistor and the first end of the second resistor respectively. The second end of the phase A temperature acquisition resistor is connected to the first end of the first capacitor and the ground signal respectively. The second end of the first resistor is connected to the first electrical signal. The second end of the second resistor is connected to the second end of the first capacitor and the temperature comparison module respectively. The first end of the phase B temperature acquisition resistor is connected to the first end of the third resistor and the first end of the fourth resistor respectively. The second end of the phase B temperature acquisition resistor is connected to the first end of the second capacitor and the ground signal respectively. The second end of the third resistor is connected to the first electrical signal. The second end of the fourth resistor is connected to the second end of the second capacitor and the temperature comparison module respectively. The first end of the C-phase temperature acquisition resistor is connected to the first end of the fifth resistor and the first end of the sixth resistor, respectively. The second end of the C-phase temperature acquisition resistor is connected to the first end of the third capacitor and the ground signal, respectively. The second end of the fifth resistor is connected to the first electrical signal, and the second end of the sixth resistor is connected to the second end of the third capacitor and the temperature comparison module, respectively.

5. The over-temperature protection device according to claim 1, characterized in that, The temperature protection reference voltage module includes a fourth capacitor, a seventh resistor, and an eighth resistor; The first terminal of the fourth capacitor is connected to the first terminal of the seventh resistor, the first terminal of the eighth resistor, and the temperature comparison module, respectively. The second terminal of the fourth capacitor is connected to the second terminal of the eighth resistor and the ground signal, respectively. The second terminal of the seventh resistor is connected to the first electrical signal.

6. The over-temperature protection device according to claim 2, characterized in that, The temperature comparison module includes an A-phase temperature comparison unit, a B-phase temperature comparison unit, a C-phase temperature comparison unit, and a control signal determination unit; The A-phase temperature comparison unit responds to the A-phase temperature level output by the A-phase field-effect transistor temperature detection unit and the temperature protection level provided by the temperature protection reference voltage module, and outputs an A-phase control signal. The B-phase temperature comparison unit responds to the B-phase temperature level output by the B-phase field-effect transistor temperature detection unit and the temperature protection level provided by the temperature protection reference voltage module, and outputs a B-phase control signal. The C-phase temperature comparison unit responds to the C-phase temperature level output by the C-phase field-effect transistor temperature detection unit and the temperature protection level provided by the temperature protection reference voltage module, and outputs a C-phase control signal. The control signal determination unit responds to the A-phase control signal, the B-phase control signal, and the C-phase control signal by outputting the power supply control signal.

7. The over-temperature protection device according to claim 6, characterized in that, The A-phase temperature comparison unit includes a ninth resistor, a fifth capacitor, a sixth capacitor, a first diode, and an A-phase comparator; the B-phase temperature comparison unit includes a tenth resistor, a seventh capacitor, an eighth capacitor, a second diode, and a B-phase comparator; the C-phase temperature comparison unit includes an eleventh resistor, a ninth capacitor, a tenth capacitor, a third diode, and a C-phase comparator; and the control signal determination unit includes a twelfth resistor, a thirteenth resistor, and an eleventh capacitor. The positive input terminal of the A-phase comparator is connected to the temperature protection reference voltage module. The inverting input terminal of the A-phase comparator is connected to the first terminal of the ninth resistor and the first terminal of the fifth capacitor, respectively. The second terminal of the fifth capacitor is connected to ground. The second terminal of the ninth resistor is connected to the A-phase field-effect transistor temperature detection unit. The ground terminal of the A-phase comparator is connected to ground. The power supply terminal of the A-phase comparator is connected to the first terminal of the sixth capacitor and the first electrical signal, respectively. The second terminal of the sixth capacitor is connected to ground. The output terminal of the A-phase comparator is connected to the first terminal of the first diode. The second terminal of the first diode is connected to the second terminal of the second diode, the second terminal of the third diode, the first terminal of the twelfth resistor, and the first terminal of the thirteenth resistor, respectively. The positive input terminal of the B-phase comparator is connected to the temperature protection reference voltage module. The inverting input terminal of the B-phase comparator is connected to the first terminal of the tenth resistor and the first terminal of the seventh capacitor, respectively. The second terminal of the seventh capacitor is connected to ground. The second terminal of the tenth resistor is connected to the B-phase field-effect transistor temperature detection unit. The ground terminal of the B-phase comparator is connected to ground. The power supply terminal of the B-phase comparator is connected to the first terminal of the eighth capacitor and the first electrical signal, respectively. The second terminal of the eighth capacitor is connected to ground. The output terminal of the B-phase comparator is connected to the first terminal of the second diode. The positive input terminal of the C-phase comparator is connected to the temperature protection reference voltage module. The inverting input terminal of the C-phase comparator is connected to the first terminal of the eleventh resistor and the first terminal of the ninth capacitor, respectively. The second terminal of the ninth capacitor is connected to ground. The second terminal of the eleventh resistor is connected to the C-phase field-effect transistor temperature detection unit. The ground terminal of the C-phase comparator is connected to ground. The power supply terminal of the C-phase comparator is connected to the first terminal of the tenth capacitor and the first electrical signal, respectively. The second terminal of the tenth capacitor is connected to ground. The output terminal of the C-phase comparator is connected to the first terminal of the third diode. The second end of the twelfth resistor is connected to the first electrical signal, the second end of the thirteenth resistor is connected to the first end of the eleventh capacitor and the power supply control module, and the second end of the eleventh capacitor is connected to the ground signal.

8. The over-temperature protection device according to claim 6, characterized in that, The power supply control module includes a fourteenth resistor, a fifteenth resistor, a sixteenth resistor, a seventeenth resistor, a twelfth capacitor, a transistor, and a field-effect transistor; The fourteenth resistor has its first end connected to the temperature comparison module. Its second end is connected to the first end of the fifteenth resistor, the first end of the twelfth capacitor, and the first end of the transistor. The second end of the fifteenth resistor is connected to the second end of the twelfth capacitor, the second end of the transistor, and ground. The third end of the transistor is connected to the first end of the sixteenth resistor. The second end of the sixteenth resistor is connected to the first end of the seventeenth resistor and the second end of the field-effect transistor. The second end of the seventeenth resistor is connected to the first end of the field-effect transistor and a second electrical signal. The third end of the field-effect transistor is connected to the power field-effect transistor module.

9. An electric vehicle controller, characterized in that, include: A power MOSFET module and an over-temperature protection device for the power MOSFET as described in any one of claims 1 to 8.

10. An electric vehicle, characterized in that, include: The electric vehicle controller as described in claim 9; The electric vehicle in question is either an electric two-wheeler or an electric three-wheeler.

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