Method for detecting damage of MOS (Metal Oxide Semiconductor) tube of brushless motor and related device
By acquiring zero-point and current position information in a three-phase brushless DC motor system and using a back EMF superposition processing method to identify abnormal MOSFETs, the problem of MOSFET anomaly detection in brushless motor systems under cost constraints is solved, thus improving system safety.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- SHENZHEN QILI TIANXIA TECH DEV CO LTD
- Filing Date
- 2026-02-27
- Publication Date
- 2026-05-12
AI Technical Summary
Under cost constraints, three-phase brushless DC motor systems lack rotor position sensors, making it impossible to effectively detect MOSFET malfunctions, which reduces safety and can easily trigger chain reactions and fires.
By acquiring the zero point and the current preset position information of the rotor of the three-phase brushless DC motor system, the current position information is determined using the three-phase state values, and abnormal MOSFETs are identified based on the position parameters. The back electromotive force superposition processing method is used to directly identify abnormal MOSFETs.
Under cost constraints, the ability to promptly identify abnormal MOSFETs and take safety measures enhances the safety of three-phase brushless DC motor systems and prevents further losses.
Smart Images
Figure CN122017512A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of anomaly detection technology, specifically to a method and related device for detecting MOSFET damage in a brushless motor. Background Technology
[0002] As a high-power module, motor drive protection is crucial. Inadequate protection can lead to anything from burnt-out MOSFETs to MOSFET conduction and board fire. MOSFET protection typically includes over-temperature protection, hardware over-current protection, and software over-current protection. Due to cost constraints, many solutions lack comparators and operational amplifiers in their main controllers, making proper hardware and software over-current protection impossible. Some solutions even omit current sampling altogether due to cost and board size limitations, omitting over-current protection. In such cases, a failed MOSFET can trigger a chain reaction, damaging a second, a third, and so on, ultimately leading to MOSFET conduction, fire, and severe damage. Summary of the Invention
[0003] This application provides a method and related device for detecting MOSFET damage in a brushless motor. Under cost constraints, it can directly identify abnormal MOSFETs based on the three-phase status values, thereby identifying abnormal MOSFETs in subsequent processing and taking corresponding safety measures to improve the safety of the three-phase brushless DC motor system.
[0004] The first aspect of this application provides a method for detecting MOSFET damage in a brushless motor. The method is applied to a three-phase brushless DC motor system, wherein the three-phase brushless DC motor system does not include a rotor position sensor. The method includes: Obtain the zero point of the three-phase brushless DC motor system, and obtain the current preset position information of the rotor of the three-phase brushless DC motor system; Based on the zero point and the current three-phase state values of the three-phase brushless DC motor system, determine the current position information of the rotor in the three-phase brushless DC motor system; The abnormal MOS transistor in the three-phase brushless DC motor system is determined based on the current location information and the current preset location information.
[0005] In one possible implementation, determining the current position information of the rotor in the three-phase brushless DC motor system based on the zero point and the current three-phase state values of the three-phase brushless DC motor system includes: Extract the high-end phase state value, low-end phase state value, and suspended phase state value from the current three-phase state values; The first position parameter is determined based on the high-end phase state value; The second position parameter is determined based on the low-end phase state value; Obtaining the back electromotive force of a three-phase brushless DC motor system; The third position parameter is determined based on the suspended phase state value, the zero point, and the back electromotive force. The current location information is determined based on the first location parameter, the second location parameter, and the third location parameter.
[0006] In one possible implementation, determining the third position parameter based on the suspended phase state value, the zero point, and the back electromotive force includes: The suspended phase state value is superimposed with the back electromotive force to obtain a first superimposed value; The third position parameter is determined based on the first superposition value and the zero point.
[0007] In one possible implementation, determining the first position parameter based on the high-end phase state value includes: If the high-end phase is determined to be in a suspended state based on the high-end phase state value, then the high-end phase state value is superimposed with the back electromotive force to obtain a second superimposed value. The first position parameter is determined based on the second superposition value and the zero point.
[0008] In one possible implementation, determining the first position parameter based on the second superposition value and the zero point includes: If the second superimposed value is less than the voltage value corresponding to the zero point, then the first position parameter is determined to be the first preset parameter, which is used to indicate that the MOS transistor is malfunctioning.
[0009] A second aspect of this application provides a MOSFET damage detection device for a brushless motor. The device is applied to a three-phase brushless DC motor system, wherein the three-phase brushless DC motor system does not include a rotor position sensor. The device comprises: The acquisition unit is used to acquire the zero point of the three-phase brushless DC motor system and to acquire the current preset position information of the rotor of the three-phase brushless DC motor system. The first determining unit is used to determine the current position information of the rotor in the three-phase brushless DC motor system based on the zero point and the current three-phase state value of the three-phase brushless DC motor system. The second determining unit is used to determine the abnormal MOS transistor in the three-phase brushless DC motor system based on the current position information and the current preset position information.
[0010] In one possible implementation, the first determining unit is specifically used for: Extract the high-end phase state value, low-end phase state value, and suspended phase state value from the current three-phase state values; The first position parameter is determined based on the high-end phase state value; The second position parameter is determined based on the low-end phase state value; Obtaining the back electromotive force of a three-phase brushless DC motor system; The third position parameter is determined based on the suspended phase state value, the zero point, and the back electromotive force. The current location information is determined based on the first location parameter, the second location parameter, and the third location parameter.
[0011] In one possible implementation, the first determining unit is specifically configured to: determine the third position parameter based on the suspended phase state value, the zero point, and the back electromotive force; The suspended phase state value is superimposed with the back electromotive force to obtain a first superimposed value; The third position parameter is determined based on the first superposition value and the zero point.
[0012] In one possible implementation, in determining the first position parameter based on the high-end phase state value, the first determining unit is specifically configured to: If the high-end phase is determined to be in a suspended state based on the high-end phase state value, then the high-end phase state value is superimposed with the back electromotive force to obtain a second superimposed value. The first position parameter is determined based on the second superposition value and the zero point.
[0013] In one possible implementation, regarding the determination of the first position parameter based on the second superposition value and the zero point, the first determining unit is specifically configured to: If the second superimposed value is less than the voltage value corresponding to the zero point, then the first position parameter is determined to be the first preset parameter, which is used to indicate that the MOS transistor is malfunctioning.
[0014] A third aspect of this application provides a terminal including a processor, an input device, an output device, and a memory, wherein the processor, input device, output device, and memory are interconnected, wherein the memory is used to store a computer program, the computer program including program instructions, and the processor is configured to invoke the program instructions to execute the step instructions as described in the first aspect of this application.
[0015] A fourth aspect of this application provides a computer-readable storage medium storing a computer program for electronic data interchange, wherein the computer program causes a computer to perform some or all of the steps described in the first aspect of this application.
[0016] A fifth aspect of this application provides a computer program product, wherein the computer program product includes a non-transitory computer-readable storage medium storing a computer program operable to cause a computer to perform some or all of the steps described in the first aspect of this application. The computer program product may be a software installation package.
[0017] Implementing the embodiments of this application has at least the following beneficial effects: By acquiring the zero point of the three-phase brushless DC motor system and the current preset position information of the rotor of the three-phase brushless DC motor system, the current position information of the rotor in the three-phase brushless DC motor system is determined based on the zero point and the current three-phase state value of the three-phase brushless DC motor system. Based on the current position information and the current preset position information, abnormal MOSFETs in the three-phase brushless DC motor system are identified. Therefore, under cost constraints, abnormal MOSFETs can be directly identified based on the three-phase state value, allowing for timely identification of abnormal MOSFETs in subsequent processing and the implementation of corresponding safety measures to improve the safety of the three-phase brushless DC motor system. Attached Figure Description
[0018] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0019] Figure 1 This application provides a flowchart illustrating a method for detecting MOSFET damage in a brushless motor. Figure 2 A schematic diagram of a back electromotive force zero-crossing detection circuit is provided for an embodiment of this application; Figure 3 This is a schematic diagram of the structure of a terminal provided in an embodiment of this application; Figure 4 This application provides a schematic diagram of the structure of a MOSFET damage detection device for a brushless motor. Detailed Implementation
[0020] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.
[0021] The terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish different objects, not to describe a specific order. 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 includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or apparatuses.
[0022] In this application, the reference to "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described in this application can be combined with other embodiments.
[0023] To better understand the MOSFET damage detection method for brushless motors provided in this application embodiment, the application scenarios of the MOSFET damage detection method for brushless motors are briefly introduced below. In some low-cost application scenarios, three-phase brushless DC motor systems may not be equipped with rotor position sensors, making it impossible to obtain the rotor position through sensors. Consequently, existing solutions cannot detect MOSFET anomalies in three-phase brushless DC motor systems, resulting in a lack of safety protection. This makes it easy for three-phase brushless DC motor systems to fail to respond promptly after MOSFET anomalies occur, leading to increased losses and reduced safety.
[0024] To address the aforementioned issues, this application provides a method and related apparatus for detecting MOSFET damage in a brushless motor. Under cost constraints, it can directly identify abnormal MOSFETs based on three-phase status values, thereby enabling timely identification of abnormal MOSFETs in subsequent processing and the implementation of corresponding safety measures to improve the safety of the three-phase brushless DC motor system.
[0025] Please see Figure 1 , Figure 1 This application provides a flowchart illustrating a method for detecting MOSFET damage in a brushless motor, as illustrated in this embodiment. Figure 1 As shown, the method is applied to a three-phase brushless DC motor system, wherein the three-phase brushless DC motor system does not include a rotor position sensor, and the method includes: 101. Obtain the zero point of the three-phase brushless DC motor system, and obtain the current preset position information of the rotor of the three-phase brushless DC motor system.
[0026] In a three-phase brushless DC motor system, there are three stator windings (U, V, W), and the rotor is a permanent magnet. The windings are typically connected in a star configuration.
[0027] It follows a six-step commutation process, specifically: to keep the rotor rotating, two phases need to be energized sequentially to generate a combined magnetic field that attracts the rotor poles to rotate. A complete electrical cycle has six different energizing combinations (e.g., UV, UW, VW, VU, WU, WV), with each step lasting 60 electrical degrees.
[0028] The current preset position information can be any of six different power-on combinations, specifically set through pre-setting or user input. This embodiment uses a current preset position information of 10X as an example for illustration.
[0029] The zero point of a three-phase brushless DC motor system can be determined by the controller continuously measuring the voltage of the three phase terminals relative to ground (or relative to the virtual neutral point). Based on the current switching state, it knows which phase is floating, then uses a comparator or ADC to read the voltage of that phase and compares it with the voltage of the virtual neutral point to determine if it has crossed zero, thus obtaining the zero point.
[0030] Specifically, zero-point detection can be performed using a back EMF zero-crossing detection circuit, such as... Figure 2 As shown.
[0031] 102. Based on the zero point and the current three-phase state values of the three-phase brushless DC motor system, determine the current position information of the rotor in the three-phase brushless DC motor system.
[0032] Specifically, a method for determining the current position information of the rotor in a three-phase brushless DC motor system based on the zero point and the current three-phase state values of the three-phase brushless DC motor system includes: Extract the high-end phase state value, low-end phase state value, and floating phase state value from the current three-phase state values; determine a first position parameter based on the high-end phase state value; determine a second position parameter based on the low-end phase state value; obtain the back electromotive force of the three-phase brushless DC motor system; determine a third position parameter based on the floating phase state value, the zero point, and the back electromotive force; determine the current position information based on the first position parameter, the second position parameter, and the third position parameter.
[0033] The current three-phase state values can be represented by 0, 1, and X. For example, assuming the zero point M of the three phases is 1 / 2VDD, the high-end U phase is 1, the low-end V phase is 0, and the floating phase W is X (uncertain).
[0034] When determining the first position parameter, the following method can be used: if the high-end phase is determined to be in a suspended state based on the high-end phase state value, the high-end phase state value is superimposed with the back electromotive force to obtain a second superimposed value; the first position parameter is determined based on the second superimposed value and the zero point.
[0035] The method for determining the first position parameter based on the second superimposed value and the zero point can be specifically as follows: if the second superimposed value is less than the voltage value corresponding to the zero point, then the first position parameter is determined to be a first preset parameter, which is used to indicate that the MOS transistor has malfunctioned.
[0036] Specifically, when the upper tube of phase U is open, it is equivalent to phase U being floating, phase V is the low-end phase with zero voltage, and phase W is a floating phase. When the superimposed BEMF of phase U is less than that of phase W, that is, less than zero point M, the detected signal is 00X. The method for determining the second position parameter is the same as the method for determining the first position parameter, and will not be repeated here.
[0037] In a specific example, a method for determining a third position parameter based on the suspended phase state value, the zero point, and the back electromotive force includes: The suspended phase state value is superimposed with the back electromotive force to obtain a first superimposed value; the third position parameter is determined based on the first superimposed value and the zero point.
[0038] In a specific example, when the lower tube of phase U is short-circuited, phase U is 0, phase V is 0, the floating phase W is zero, the superimposed back electromotive force bemf, the voltage at point W is greater than 0, and similarly the voltage at point M is greater than 0, and the detected signal is 00X.
[0039] 103. Determine the abnormal MOS transistor in the three-phase brushless DC motor system based on the current position information and the current preset position information.
[0040] If the current position information differs from the preset position information, the abnormal MOSFET in the three-phase brushless DC motor system is identified. Specifically, the specific MOSFET causing the abnormality can be determined based on the current state values of the high-side and low-side phases.
[0041] For example, when the lower MOSFET of phase U is short-circuited, the internal resistance of the MOSFET is 0R, and the voltage of phase U is 0. At this time, the detected position signal is 00X, which does not match the current phase 10X. Or when the upper MOSFET of phase V is open-circuited, the internal resistance of the upper MOSFET is 0R, and the voltage of phase V is VDD. The detected signal is 11X, which does not match the current phase 10X.
[0042] Of course, the zero point M may change; it can be any value other than 1 / 2VDD. When the lower tube of phase U is short-circuited, phase U is 0, phase V is 0, and the floating phase W is zero. With the superimposed back electromotive force (BEMF), the voltage at point W is greater than 0. Similarly, the voltage at point M is greater than 0, and the detected signal is 00X, which does not match the current phase 10X. When the upper tube of phase V is short-circuited, the high-side phase U is VDD, the low-side phase V is VDD, and the floating phase W is VDD. With the superimposed BEMF, the voltage of the floating phase W is less than VDD. Similarly, the voltage at point M is less than VDD, and the detected signal is 11X, which does not match the current phase 10X.
[0043] The above describes the detection and analysis of MOSFET short-circuit damage. Open-circuit damage of the MOSFET can also be detected. When the upper MOSFET of phase U is open, it's equivalent to phase U being floating, phase V is the low-side phase with zero voltage, and phase W is a floating phase. When the superimposed BEMF of phase U is less than that of phase W, i.e., less than zero point M, the detected signal is 00X, which does not match the current phase's 10X. Similarly, when the lower MOSFET of phase V is open, a signal of 11X will be detected, which also does not match the current phase's 10X. In one specific implementation, this application embodiment also provides a method for detecting MOSFET damage in a brushless motor, as follows: In a sensored square wave, the position of the motor in the six-step commutation is determined by detecting the switching of three Hall effect sensors. Similarly, in a sensorless square wave, a comparator can be used to compare the zero point with the three phases to determine the motor's position in the six-step commutation. The method for detecting MOSFET damage involves checking whether the detected position matches the theoretical position to determine if the motor is operating abnormally and whether the MOSFET is damaged.
[0044] Assuming the zero point M of the three phases is 1 / 2VDD, the high-side U phase is 1, the low-side V phase is 0, and the floating phase W is X (uncertain). Taking the motor running and the current phase as 10X as an example: When the lower U phase transistor is short-circuited, the MOS internal resistance is 0R, the U phase voltage is 0, and the detected position signal is 00X, which does not match the current phase 10X. Alternatively, when the upper V phase transistor is open-circuited, the upper transistor internal resistance is 0R, the V phase voltage is VDD, and the detected signal is 11X, which also does not match the current phase 10X.
[0045] Of course, zero point M cannot always be 1 / 2VDD. When the lower tube of phase U is short-circuited, phase U is 0, phase V is 0, and the floating phase W is zero. With the superimposed back electromotive force (BEMF), the voltage at point W is greater than 0. Similarly, the voltage at point M is greater than 0, and the detected signal is 00X, which does not match the current phase 10X. When the upper tube of phase V is short-circuited, the high-side phase U is VDD, the low-side phase V is VDD, and the floating phase W is VDD. With the superimposed BEMF, the voltage at the floating phase W is less than VDD. Similarly, the voltage at point M is less than VDD, and the detected signal is 11X, which does not match the current phase 10X.
[0046] The above is the detection analysis of MOSFET short-circuit damage. MOSFET open-circuit damage can also be detected. When the upper MOSFET of phase U is open, it's equivalent to phase U being floating, phase V is the low-side phase with zero voltage, and phase W is a floating phase. When the superimposed bemf of phase U is less than that of phase W, that is, less than zero point M, the detected signal is 00X, which does not match the current phase's 10X. Similarly, when the lower MOSFET of phase V is open, a signal of 11X will be detected, which also does not match the current phase's 10X.
[0047] For examples consistent with the above embodiments, please refer to... Figure 3 , Figure 3 This is a schematic diagram of the structure of a terminal provided in an embodiment of this application, such as... Figure 3 As shown, it includes a processor, an input device, an output device, and a memory, which are interconnected. The memory is used to store a computer program, which includes program instructions. The processor is configured to call the program instructions. The program includes instructions for performing the following steps. Obtain the zero point of the three-phase brushless DC motor system, and obtain the current preset position information of the rotor of the three-phase brushless DC motor system; Based on the zero point and the current three-phase state values of the three-phase brushless DC motor system, determine the current position information of the rotor in the three-phase brushless DC motor system; The abnormal MOS transistor in the three-phase brushless DC motor system is determined based on the current location information and the current preset location information.
[0048] The above mainly describes the solutions of the embodiments of this application from the perspective of the method execution process. It is understood that, in order to achieve the above functions, the terminal includes the corresponding hardware structure and / or software modules for executing each function. Those skilled in the art should readily recognize that, in conjunction with the units and algorithm steps of the various examples described in the embodiments provided herein, this application can be implemented in hardware or a combination of hardware and computer software. Whether a function is executed in hardware or by computer software driving hardware depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.
[0049] This application embodiment can divide the terminal into functional units according to the above method example. For example, each function can be divided into a separate functional unit, or two or more functions can be integrated into one processing unit. The integrated unit can be implemented in hardware or as a software functional unit. It should be noted that the unit division in this application embodiment is illustrative and only represents one logical functional division. In actual implementation, there may be other division methods.
[0050] For those consistent with the above, please refer to Figure 4 , Figure 4 This application provides a schematic diagram of the structure of a MOSFET damage detection device for a brushless motor, as shown in the embodiment. Figure 4 As shown, the brushless motor MOSFET damage detection device is applied to a three-phase brushless DC motor system. The three-phase brushless DC motor system does not include a rotor position sensor. The device includes: The acquisition unit 301 is used to acquire the zero point of the three-phase brushless DC motor system and to acquire the current preset position information of the rotor of the three-phase brushless DC motor system. The first determining unit 302 is used to determine the current position information of the rotor in the three-phase brushless DC motor system based on the zero point and the current three-phase state value of the three-phase brushless DC motor system. The second determining unit 303 is used to determine the abnormal MOS transistor in the three-phase brushless DC motor system based on the current position information and the current preset position information.
[0051] In one possible implementation, the first determining unit 302 is specifically used for: Extract the high-end phase state value, low-end phase state value, and suspended phase state value from the current three-phase state values; The first position parameter is determined based on the high-end phase state value; The second position parameter is determined based on the low-end phase state value; Obtaining the back electromotive force of a three-phase brushless DC motor system; The third position parameter is determined based on the suspended phase state value, the zero point, and the back electromotive force. The current location information is determined based on the first location parameter, the second location parameter, and the third location parameter.
[0052] In one possible implementation, the first determining unit 302 is specifically configured to: determine the third position parameter based on the suspended phase state value, the zero point, and the back electromotive force; The suspended phase state value is superimposed with the back electromotive force to obtain a first superimposed value; The third position parameter is determined based on the first superposition value and the zero point.
[0053] In one possible implementation, in determining the first position parameter based on the high-end phase state value, the first determining unit 302 is specifically configured to: If the high-end phase is determined to be in a suspended state based on the high-end phase state value, then the high-end phase state value is superimposed with the back electromotive force to obtain a second superimposed value. The first position parameter is determined based on the second superposition value and the zero point.
[0054] In one possible implementation, in determining the first position parameter based on the second superposition value and the zero point, the first determining unit 302 is specifically configured to: If the second superimposed value is less than the voltage value corresponding to the zero point, then the first position parameter is determined to be the first preset parameter, which is used to indicate that the MOS transistor is malfunctioning.
[0055] This application also provides a computer storage medium storing a computer program for electronic data interchange, which causes a computer to perform some or all of the steps of any of the brushless motor MOSFET damage detection methods described in the above method embodiments.
[0056] This application also provides a computer program product, which includes a non-transitory computer-readable storage medium storing a computer program that causes a computer to perform some or all of the steps of any of the brushless motor MOSFET damage detection methods described in the above method embodiments.
[0057] It should be noted that, for the sake of simplicity, the foregoing method embodiments are all described as a series of actions. However, those skilled in the art should understand that this application is not limited to the described order of actions, as some steps may be performed in other orders or simultaneously according to this application. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are preferred embodiments, and the actions and modules involved are not necessarily essential to this application.
[0058] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.
[0059] In the several embodiments provided in this application, it should be understood that the disclosed apparatus can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between devices or units may be electrical or other forms.
[0060] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.
[0061] Furthermore, the functional units in the various embodiments of the application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software program module.
[0062] If the integrated unit is implemented as a software program module and sold or used as an independent product, it can be stored in a computer-readable storage device (CMD). Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a memory and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned memory includes various media capable of storing program code, such as USB flash drives, read-only memory (ROM), random access memory (RAM), portable hard drives, magnetic disks, or optical disks.
[0063] Those skilled in the art will understand that all or part of the steps in the various methods of the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage device, which may include: a flash drive, a read-only memory, a random access memory, a magnetic disk, or an optical disk, etc.
[0064] The embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.
Claims
1. A method for detecting MOSFET damage in a brushless motor, characterized in that, The method is applied to a three-phase brushless DC motor system, wherein the three-phase brushless DC motor system does not include a rotor position sensor, and the method includes: Obtain the zero point of the three-phase brushless DC motor system, and obtain the current preset position information of the rotor of the three-phase brushless DC motor system; Based on the zero point and the current three-phase state values of the three-phase brushless DC motor system, determine the current position information of the rotor in the three-phase brushless DC motor system; The abnormal MOS transistor in the three-phase brushless DC motor system is determined based on the current location information and the current preset location information.
2. The method for detecting MOSFET damage in a brushless motor according to claim 1, characterized in that, The step of determining the current position information of the rotor in the three-phase brushless DC motor system based on the zero point and the current three-phase state values of the three-phase brushless DC motor system includes: Extract the high-end phase state value, low-end phase state value, and suspended phase state value from the current three-phase state values; The first position parameter is determined based on the high-end phase state value; The second position parameter is determined based on the low-end phase state value; Obtaining the back electromotive force of a three-phase brushless DC motor system; The third position parameter is determined based on the suspended phase state value, the zero point, and the back electromotive force. The current location information is determined based on the first location parameter, the second location parameter, and the third location parameter.
3. The method for detecting MOSFET damage in a brushless motor according to claim 2, characterized in that, The step of determining the third position parameter based on the suspended phase state value, the zero point, and the back electromotive force includes: The suspended phase state value is superimposed with the back electromotive force to obtain a first superimposed value; The third position parameter is determined based on the first superposition value and the zero point.
4. The method for detecting MOSFET damage in a brushless motor according to claim 2 or 3, characterized in that, Determining the first position parameter based on the high-end phase state value includes: If the high-end phase is determined to be in a suspended state based on the high-end phase state value, then the high-end phase state value is superimposed with the back electromotive force to obtain a second superimposed value. The first position parameter is determined based on the second superposition value and the zero point.
5. The method for detecting MOSFET damage in a brushless motor according to claim 4, characterized in that, The step of determining the first position parameter based on the second superposition value and the zero point includes: If the second superimposed value is less than the voltage value corresponding to the zero point, then the first position parameter is determined to be the first preset parameter, which is used to indicate that the MOS transistor is malfunctioning.
6. A device for detecting MOSFET damage in a brushless motor, characterized in that, The device is applied to a three-phase brushless DC motor system, wherein the three-phase brushless DC motor system does not include a rotor position sensor, and the device includes: The acquisition unit is used to acquire the zero point of the three-phase brushless DC motor system and to acquire the current preset position information of the rotor of the three-phase brushless DC motor system. The first determining unit is used to determine the current position information of the rotor in the three-phase brushless DC motor system based on the zero point and the current three-phase state value of the three-phase brushless DC motor system. The second determining unit is used to determine the abnormal MOS transistor in the three-phase brushless DC motor system based on the current position information and the current preset position information.
7. The MOSFET damage detection device for brushless motors according to claim 6, characterized in that, The first determining unit is specifically used for: Extract the high-end phase state value, low-end phase state value, and suspended phase state value from the current three-phase state values; The first position parameter is determined based on the high-end phase state value; The second position parameter is determined based on the low-end phase state value; Obtaining the back electromotive force of a three-phase brushless DC motor system; The third position parameter is determined based on the suspended phase state value, the zero point, and the back electromotive force. The current location information is determined based on the first location parameter, the second location parameter, and the third location parameter.
8. The MOSFET damage detection device for brushless motors according to claim 7, characterized in that, In determining the third position parameter based on the suspended phase state value, the zero point, and the back electromotive force, the first determining unit is specifically used for: The suspended phase state value is superimposed with the back electromotive force to obtain a first superimposed value; The third position parameter is determined based on the first superposition value and the zero point.
9. A terminal, characterized in that, The system includes a processor, an input device, an output device, and a memory, which are interconnected. The memory is used to store a computer program, which includes program instructions. The processor is configured to invoke the program instructions to perform the method as described in any one of claims 1-5.
10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program, the computer program including program instructions that, when executed by a processor, cause the processor to perform the method as described in any one of claims 1-5.