Short-circuit fault detection system and method

Abstract

Embodiments of the present invention provide a short-circuit fault detection system and method. The short-circuit fault detection system includes a power supply module for supplying power to the detection system; a drive module coupled to the power supply module and a motor for converting the system voltage provided by the power supply module into a voltage for the motor to operate; a current sampling module coupled to the drive module for sampling the phase current of the motor; and a fault detection module coupled to the power supply module and the current sampling module, configured to acquire the phase voltage corresponding to the phase current of the motor and to perform an initialization self-test of the detection system based on the phase voltage.

Description

Technical Field

[0001] Cross - reference to Related Applications This application claims the priority of Chinese Patent Application No. 202310981816.6, titled "Short - Circuit Fault Detection System and Method", filed on August 4, 2023, and the entire content of the said application is incorporated herein by reference.

[0002] Technical Field This application relates to the field of integrated circuits, and more specifically, to a short - circuit fault detection system and method.

Background Art

[0003] In a three - phase motor control system, usually, a phase - line switch is installed on the motor's phase line for the purpose of motor open - phase protection. In the case of an application design that employs a MOSFET as the phase - line switch, there may be random hardware faults such as open - circuit faults and short - circuit faults in the MOSFET. When the phase - line MOSFET switch fails, the switching function is disabled, affecting the control of the motor. For the open - circuit fault of the MOSFET, diagnosis can be performed when the control system is operating in real - time. For the short - circuit fault of the MOSFET, diagnosis cannot be performed when the control system is operating in real - time. To identify such a fault, it is necessary to diagnose it in the power - on / off self - test process of the control system.

[0004] In a three - phase motor control system that uses a phase - line MOSFET switch and a high - side MOSFET switch simultaneously, it is necessary to utilize the charge - pump output to form a current closed - loop for the high - side MOSFET switch and determine whether a short - circuit fault has occurred in the phase - line MOSFET switch based on whether current is generated in the closed - loop. Therefore, there is a need for a short - circuit fault detection system with a simple structure and high efficiency.

Summary of the Invention

Means for Solving the Problems

[0005] Embodiments of the present invention provide a short-circuit fault detection system comprising: a power supply module for supplying power to the detection system; a drive module coupled to the power supply module and a motor for converting the system voltage provided by the power supply module into a voltage for the motor to operate; a current sampling module coupled to the drive module for sampling the phase current of the motor; and a fault detection module coupled to the power supply module and the current sampling module, configured to acquire the phase voltage corresponding to the phase current of the motor and to perform an initialization self-test of the detection system based on the phase voltage.

[0006] Embodiments of the present invention provide a short-circuit fault detection method for a short-circuit fault detection system, the detection system comprising a power supply module, a drive module, a current sampling module, and a fault detection module, the detection method comprising the steps of: supplying power to the detection system by the power supply module; converting the system voltage provided by the power supply module to a voltage for motor operation by the drive module; sampling the phase current of the motor by the current sampling module; and obtaining the phase voltage corresponding to the phase current of the motor by the fault detection module and performing an initialization self-test of the detection system based on the phase voltage.

[0007] To more clearly explain the technical solution of the embodiment of the present application, the drawings relating to the embodiment of the present application are briefly described below. Those skilled in the art can obtain other drawings based on these drawings without requiring any creative effort. The drawings are as follows. [Brief explanation of the drawing]

[0008] [Figure 1] This diagram shows a schematic structure of a MOSFET short-circuit fault detection system for a three-phase bridge inverter circuit. [Figure 2] A schematic diagram of the short-circuit fault detection system according to an embodiment of the present invention is shown. [Figure 3]Another schematic diagram of the short-circuit fault detection system according to an embodiment of the present invention is shown. [Figure 4] A schematic flowchart of the short-circuit fault detection method according to the embodiment of this application is shown. [Figure 5] Another schematic flowchart of the short-circuit fault detection method according to the embodiment of the present invention is shown. [Modes for carrying out the invention]

[0009] The features and exemplary embodiments of each aspect of the present application are described in detail below. To further clarify the purpose, solution, and advantages of the present application, the details of the present application are described below in conjunction with the drawings and specific embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the present application. Those skilled in the art can implement the present application even without some of these specific details. The following description of embodiments is merely to provide a better understanding of the present application by illustrating its examples.

[0010] It should be noted that, in this specification, relational terms such as "first," "second," and "third" are used solely to distinguish one entity or operation from another, and do not necessarily require or imply that such an actual relationship or order exists between these entities or operations. Furthermore, the terms "includes," "incorporates," and any other variations thereof are intended to cover non-exclusive inclusion, and a process, method, article, or apparatus that includes a set of elements includes not only those elements but also other elements not explicitly listed, or elements specific to such process, method, article, or apparatus. Unless further limited, the elements defined by the phrase "...includes" do not preclude the existence of additional elements in the process, method, article, or apparatus that includes those elements.

[0011] As mentioned earlier, MOSFET short-circuit failures cannot be diagnosed in real time while the control system is operating and must be diagnosed during the control system's power-on / off self-test process. For the N-channel MOSFET power-on self-test, it is necessary to ensure that the power supply voltage is applied to the MOSFET's drain electrode (D electrode) and that a higher charge pump voltage is applied to the MOSFET's gate electrode (G electrode) than that of the D electrode.

[0012] Figure 1 shows a schematic diagram of a MOSFET short-circuit fault detection system for a conventional three-phase bridge inverter circuit.

[0013] As shown in Figure 1, the MOSFET short-circuit fault detection system includes an MCU module, a pre-driver IC, a three-phase bridge drive circuit, a phase MOSFET switch, a pull-up resistor R3, and a voltage divider circuit. The MCU module monitors the motor terminal voltage using the voltage divider circuit and performs AD sampling using an ADC inside the MCU module. The voltage divider circuit consists of an upper voltage divider resistor R1 and a lower voltage divider resistor R2 connected in series.

[0014] In this MOSFET short-circuit fault detection system, the single phase of the motor is connected to the input power supply via a pull-up resistor R3. For example, if a short-circuit fault occurs in the phase MOSFET switch, the power supply current flows through the motor coil and the short-circuited MOSFET via the pull-up resistor R3, generating a voltage in the voltage divider circuit, thereby detecting the short-circuit fault of the MOSFET.

[0015] The detection system has the following drawbacks. Firstly, its complex circuit structure increases circuit and resource costs. Specifically, in addition to the devices that guarantee the normal operation of the circuit, three resistors R1, R2, and R3 are added to the detection system, and in addition to the resources that guarantee the normal operation of the circuit, one ADC port is also added. Secondly, an additional short-circuit fault diagnosis program is added, increasing software costs. For example, the additional ADC port on the MCU module needs to monitor the real-time voltage of the motor terminals. If the real-time voltage is within a certain range, the system is determined to be normal; if the real-time voltage is within a different range, a short-circuit fault in the phase MOSFET switch is determined to have occurred. Therefore, the system software needs to make judgments for each different voltage range, and setting different voltage range values ​​also increases software overhead.

[0016] This invention provides a detection system for detecting short-circuit faults in a phase-line MOSFET switch in a three-phase motor control system that simultaneously uses a phase-line MOSFET switch and a high-side MOSFET switch. The detection system according to the embodiment of this invention can detect short-circuit faults in a phase-line MOSFET switch, perform an initialization self-test of the detection system, enter an operating mode for normal motor control, and simultaneously enable control of the high-side MOSFET switch, without adding circuit cost or software overhead.

[0017] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Referring to Figure 2, which shows a schematic diagram of the short-circuit fault detection system according to an embodiment of the present invention, the detection system may be used for short-circuit fault detection in a three-phase motor control system that simultaneously uses both a phase MOSFET switch and a high-side MOSFET switch.

[0018] As shown in Figure 2, in some embodiments, the short-circuit fault detection system according to the embodiment of the present invention includes a power supply module, a drive module, a current sampling module, and a fault detection module.

[0019] In some embodiments, a power module may be used to supply power to the detection system. A drive module may be coupled to the power module and a motor (e.g., a three-phase brushless motor) and may be used to convert the system voltage provided by the power module into a voltage for the motor to operate. A current sampling module may be coupled to the drive module and may be used to sample the phase currents of the motor. In some embodiments, a fault detection module may also be coupled to the power module and the current sampling module and may be configured to acquire the phase voltages corresponding to the phase currents of the motor and to perform an initialization self-test of the detection system based on the phase voltages.

[0020] Refer to Figure 3, which shows another schematic diagram of the short-circuit fault detection system according to an embodiment of the present invention.

[0021] In some embodiments, as shown in Figure 3, the fault detection module in the detection system may include a microprogrammed control unit (MCU), and the fault detection module may be further configured to perform an initialization self-test of the detection system by setting the state of port PORT1 of the microprogrammed control unit (MCU). Selectively, port PORT1 may be one of the input / output ports of the microprogrammed control unit (MCU) and can be used as an input and / or output of the microprogrammed control unit (MCU). In some embodiments, setting the state of port PORT1 may include setting port PORT1 to either a low-level output state or a high-impedance input state.

[0022] In some embodiments, as shown in FIG. 3, the microprogram control unit MCU may be coupled to the current sampling module via its ADC input ports u_ADC, v_ADC, and w_ADC to obtain the phase line voltage corresponding to the phase line current of the motor sampled by the current sampling module.

[0023] Specifically, the microprogram control unit MCU obtains, via the ADC input ports u_ADC, v_ADC, and w_ADC, the voltage signals obtained after modulation processing of the currents of different phase lines of the motor (for example, three-phase currents) flowing through the current sampling resistors in the current sampling module, respectively, and can determine the magnitude of the phase line current based on the voltage signals. For example, when there is no current loop formed in the phase line (that is, no short-circuit fault occurs in that phase line), the ADC sampling voltage signal corresponding to that phase line obtained by the microprogram control unit MCU is zero; when a current loop is formed in the phase line (that is, a short-circuit fault occurs in that phase line), the corresponding ADC sampling voltage signal is a preset value. It should be noted that the preset value of the voltage signal in the present application may be set based on a specific circuit structure and is not limited here.

[0024] In some embodiments, as shown in FIG. 3, the fault detection module may further include a drive integrated circuit IC, and the microprogram control unit MCU may be coupled to the drive integrated circuit IC via port PORT1 and may be configured to control the output state of the drive integrated circuit IC by means of port PORT1.

[0025] In some embodiments, the drive integrated circuit IC may include a charge pump output voltage terminal CP and a gate drive output voltage terminal GD, and controlling the output state of the drive integrated circuit IC by port PORT1 may include enabling the charge pump output voltage terminal CP and disabling the gate drive output voltage terminal GD when port PORT1 is set to a low-level output state, and enabling both the charge pump output voltage terminal CP and the gate drive output voltage terminal GD when port PORT1 is set to a high-impedance input state.

[0026] In some embodiments, as shown in Figure 3, the power supply module may include a system power supply VBATT and a first transistor Q1, and the fault detection module and the drive module may be coupled to the system power supply VBATT via the first transistor Q1.

[0027] In this application, the system power supply VBATT is a system power supply used to power the detection system and provide the system voltage. The detection system according to the embodiment of this application may further include a chip power supply VCC for supplying power to the microprogram control unit MCU and drive integrated circuit IC in the detection system. Furthermore, in this application, the first transistor Q1 may be a metal-oxide semiconductor field-effect transistor (MOSFET) or any other type of transistor and can be used as a high-side MOSFET switch in the detection system. It should be noted that this application does not limit the specific structure and parameters of the first transistor Q1.

[0028] In some embodiments, the fault detection module may be further configured to control the on / off state of the first transistor Q1 by setting the state of port PORT1 of the microprogram control unit (MCU). Optionally, in some embodiments, the first transistor Q1 may be turned on when port PORT1 is set to a low-level output state or a high-impedance input state.

[0029] In some embodiments, as shown in Figure 3, the drive module may include a three-phase bridge drive circuit driven by a drive signal (shown as B6_CTRL in Figure 3). For example, the drive signal B6_CTRL may be a PWM drive signal from a microprogram control unit (MCU), and is used to drive switches on the bridge arms of the three-phase bridge drive circuit and to control the operation of the motor. It should be noted that this application does not limit the specific structure and parameters of the three-phase bridge drive circuit, and any form of three-phase bridge drive circuit may be applied to this application. Furthermore, this application does not specifically limit the form and parameters of the PWM drive signal used in the three-phase bridge drive circuit.

[0030] In some embodiments, the drive module may further include a second transistor Q2, a third transistor Q3, and a fourth transistor Q4, the second transistor Q2, the third transistor Q3, and the fourth transistor Q4 may each be coupled to different phases of the three-phase bridge drive circuit and the motor.

[0031] As shown in Figure 3, the three-phase bridge drive circuit, as well as the second transistor Q2, the third transistor Q3, and the fourth transistor Q4, are coupled to the three phase lines U, V, and W of the motor. In this application, for example, the second transistor Q2, the third transistor Q3, and the fourth transistor Q4 may be metal-oxide semiconductor field-effect transistors (MOSFETs) or any other type of transistor, and may be used as phase-line MOSFET switches in the detection system. It should be noted that this application does not limit the specific structure and parameters of the second transistor Q2, the third transistor Q3, and the fourth transistor Q4.

[0032] In some embodiments, when port PORT1 of the microprogram control unit MCU is set to a low-level output state, the second transistor Q2, the third transistor Q3, and the fourth transistor Q4 may be turned off, and when port PORT1 of the microprogram control unit MCU is set to a high-impedance input state, the second transistor Q2, the third transistor Q3, and the fourth transistor Q4 may be turned on.

[0033] As described above, in the short-circuit fault detection system, when port PORT1 of the microprogram control unit MCU is set to a low-level output state, the charge pump output voltage terminal CP of the drive integrated circuit IC is activated, the first transistor Q1 is turned on, and the detection system can perform an initialization self-test. When port PORT1 is set to a high-impedance input state, both the charge pump output voltage terminal CP and the gate drive output voltage terminal GD of the drive integrated circuit IC are activated, the first transistor Q1 is turned on, and the second transistor Q2, the third transistor Q3, and the fourth transistor Q4 are also turned on, the drive module enters a normal operating state, and the motor can be driven by a motor drive signal generated by the three-phase bridge drive circuit under the control of a PWM drive signal.

[0034] In some embodiments, performing an initialization self-test of the detection system may include the fault detection module determining, based on the phase voltage, whether a short-circuit fault has occurred in one or more of the second transistor Q2, the third transistor Q3, and the fourth transistor Q4. In some embodiments, determining whether a short-circuit fault has occurred in one or more of the second transistor Q2, the third transistor Q3, and the fourth transistor Q4 may include determining that a short-circuit fault has occurred in one or more transistors if the phase voltage of the phase line to which one or more of the second transistor Q2, the third transistor Q3, and the fourth transistor Q4 are coupled is not zero, for example, if the phase voltage is a preset value.

[0035] In some embodiments, as shown in Figure 3, the current sampling module may include a first resistor R1, a second resistor R2, and a third resistor R3 for sampling the different phase currents of the motor, respectively. Also in some embodiments, as shown in Figure 3, the fault detection module may further include a fourth resistor R4, and the port PORT1 of the microprogram control unit MCU and the gate drive output voltage terminal GD of the aforementioned drive integrated circuit IC are coupled to the chip power supply VCC included in the detection system via the fourth resistor R4. It should be noted that the resistance values ​​of the first resistor R1, the second resistor R2, the third resistor R3, and the fourth resistor R4 may be set according to the needs of the actual circuit design and are not limited herein.

[0036] The elements used in the short-circuit fault detection system according to the embodiment of this application are all general-purpose motor control elements, requiring no additional elements, resulting in a relatively simple circuit structure and low manufacturing costs. Furthermore, the short-circuit fault detection system according to the embodiment of this application can simultaneously achieve initialization self-testing and normal motor control by setting the state of the same port, and also has low software overhead.

[0037] The short-circuit fault detection method according to an embodiment of the present application will be described below with reference to Figures 3 and 4, with Figure 4 showing a schematic flowchart of the short-circuit fault detection method according to an embodiment of the present application. The short-circuit fault detection method may also be used in a short-circuit fault detection system according to an embodiment of the present application, specifically, the detection system includes a power supply module, a drive module, a current sampling module, and a fault detection module. Details of the power supply module, drive module, current sampling module, and fault detection module can be found in the above description of the short-circuit fault detection system and will not be repeated here.

[0038] In some embodiments, as shown in Figure 4, the short-circuit fault detection method includes the steps of: supplying power to the detection system by a power supply module; converting the system voltage provided by the power supply module to a voltage for motor operation by a drive module; sampling the phase current of the motor by a current sampling module; and obtaining the phase voltage corresponding to the motor's phase current by a fault detection module and performing an initialization self-test of the detection system based on the phase voltage.

[0039] In some embodiments, referring to Figures 3 and 4, the fault detection module may include a microprogrammed control unit (MCU), and the detection method may further include the step of performing an initialization self-test of the detection system by setting the state of port PORT1 of the microprogrammed control unit (MCU) by the fault detection module, wherein setting the state of port PORT1 of the microprogrammed control unit (MCU) includes setting port PORT1 to either a low-level output state or a high-impedance input state.

[0040] In some embodiments, referring to Figures 3 and 4, the fault detection module may further include a drive integrated circuit IC, and performing an initialization self-test of the detection system may include setting port PORT1 of the microprogram control unit MCU to a low-level output state so as to enable the charge pump output voltage terminal CP of the drive integrated circuit IC and disable the gate drive output voltage terminal GD of the drive integrated circuit IC.

[0041] In some embodiments, performing an initialization self-test of the detection system may further include, if it is detected that the phase voltage is zero, setting port PORT1 of the microprogram control unit MCU to a high impedance input state so that both the charge pump output voltage terminal CP and the gate drive output voltage terminal GD of the drive integrated circuit IC are enabled and the motor enters an operating mode for normal control; and if it is detected that the phase voltage is not zero, determining that a short-circuit fault has occurred.

[0042] In some embodiments, referring to Figures 3 and 4, the power supply module may include a system power supply VBATT and a first transistor Q1, and the fault detection module and the drive module are coupled to the system power supply VBATT via the first transistor Q1. The detection method may further include the step of controlling the on and off of the first transistor Q1 by setting the state of port PORT1 of the microprogram control unit MCU using the fault detection module. Selectively, in some embodiments, the first transistor Q1 is turned on when port PORT1 is set to a low-level output state or a high-impedance input state.

[0043] In some embodiments, referring to Figures 3 and 4, the drive module may include a three-phase bridge drive circuit, as well as a second transistor Q2, a third transistor Q3, and a fourth transistor Q4. Details of these elements can be found in the above description of the drive module in the fault detection system, which will not be repeated here. In some embodiments, when port PORT1 of the microprogram control unit MCU is set to a low-level output state, the second transistor Q2, the third transistor Q3, and the fourth transistor Q4 are turned off, and when port PORT1 of the microprogram control unit MCU is set to a high-impedance input state, the second transistor Q2, the third transistor Q3, and the fourth transistor Q4 are turned on.

[0044] Therefore, in this short-circuit fault detection method, when port PORT1 of the microprogram control unit MCU is set to a low-level output state, the charge pump output voltage terminal CP of the drive integrated circuit IC becomes active, the first transistor Q1 turns on, and the initialization self-test of the detection system can be performed. When port PORT1 is set to a high-impedance input state, both the charge pump output voltage terminal CP and the gate drive output voltage terminal GD of the drive integrated circuit IC become active, the first transistor Q1 turns on, and the second transistor Q2, the third transistor Q3, and the fourth transistor Q4 also turn on, the drive module enters a normal operating state, and the motor can be driven by a motor drive signal generated by the three-phase bridge drive circuit under the control of a PWM drive signal.

[0045] In some embodiments, performing an initialization self-test of the detection system may include the fault detection module determining, based on the phase voltage, whether a short-circuit fault has occurred in one or more of the second transistor Q2, the third transistor Q3, and the fourth transistor Q4. Furthermore, in some embodiments, determining whether a short-circuit fault has occurred in one or more of the second transistor Q2, the third transistor Q3, and the fourth transistor Q4 may include determining that a short-circuit fault has occurred in one or more transistors if the phase voltage of the phase line to which one or more of the second transistor Q2, the third transistor Q3, and the fourth transistor Q4 are coupled is not zero, for example, if the phase voltage is a preset value.

[0046] The elements used in the short-circuit fault detection method according to the embodiment of this application are all general-purpose motor control elements, and no further elements are added, resulting in a relatively simple circuit structure. Furthermore, the short-circuit fault detection method according to the embodiment of this application can simultaneously achieve initialization self-test and normal motor control by setting the state of the same port, and also has low software overhead. Although this application has described the steps of the short-circuit fault detection method in a specific order, it should be understood that these steps may be performed in an order different from the order shown in Figure 4.

[0047] Refer to Figure 5, which shows another schematic flowchart of the short-circuit fault detection method according to an embodiment of the present application. The short-circuit fault detection method may be used in a short-circuit fault detection system according to an embodiment of the present application, specifically, the detection system includes a power supply module, a drive module, a current sampling module, and a fault detection module. Details of the power supply module, drive module, current sampling module, and fault detection module can be found in the above description of the short-circuit fault detection system, which will not be repeated here.

[0048] As shown in Figure 5, when a higher-level system (e.g., vehicle system, motor system, etc.) is woken up to execute a power-on initialization program, the completion flag bit of that power-on initialization program is identified. If power-on initialization is not complete, the initialization cycle process is re-entered. Once power-on initialization is complete, the initialization settings for the basic functions of the higher-level system are completed, and the short-circuit fault detection function can be configured.

[0049] In some embodiments, as shown in Figure 5, the setting of the short-circuit fault detection function may include setting port PORT1 of the microprogram control unit MCU to a low-level output state, setting the drive control mode of the drive signal B6_CTRL, and enabling the current detection function of the ADC input ports u_ADC, v_ADC, and w_ADC of the microprogram control unit MCU.

[0050] As described above, when port PORT1 of the microprogram control unit MCU is set to a low-level output state, the charge pump output voltage terminal CP of the drive integrated circuit IC is enabled, and the gate drive output voltage terminal GD is disabled. At this time, the first transistor Q1 of the power supply module is turned on, and the second transistor Q2, third transistor Q3, and fourth transistor Q4 of the drive module are turned off. The three-phase bridge drive circuit in the drive module controls the on / off switching of its bridge arm based on the input PWM drive signal to generate the motor drive signal. When the second transistor Q2, third transistor Q3, and fourth transistor Q4 are turned off, no current loop is formed in any of the three phase lines U, V, and W of the motor.

[0051] In some embodiments, after the short-circuit fault detection function has been configured, it is detected whether the sampling voltage signals of the ADC input ports u_ADC, v_ADC, and w_ADC of the microprogram control unit (MCU) are zero.

[0052] If the sampling voltage signals of the ADC input ports u_ADC, v_ADC, and w_ADC are all detected as 0, it indicates that there are no short-circuit faults in the second transistor Q2, the third transistor Q3, and the fourth transistor Q4, and the initialization self-test for short-circuit fault detection is completed. Next, port PORT1 of the microprogram control unit MCU is set to a high-impedance input state, and port PORT1 is set to a high level by the pull-up resistor R4, the charge pump output voltage terminal CP of the drive integrated circuit IC is enabled, and the gate drive output voltage terminal GD of the drive integrated circuit IC is also set to a high level and enabled by the pull-up resistor R4. At this time, the first transistor Q1 of the power supply module is turned on, and the second transistor Q2, the third transistor Q3, and the fourth transistor Q4 of the drive module are also turned on, and the system enters an operating mode for normal motor control, driving the motor operation with a motor drive signal generated by the three-phase bridge drive circuit under the control of the PWM drive signal.

[0053] If one or more of the sampling voltage signals from the ADC input ports u_ADC, v_ADC, and w_ADC are detected as non-zero, it indicates that an unexpected current loop has formed in the phase corresponding to the non-zero sampling voltage signal, i.e., a short-circuit failure has occurred in the transistors corresponding to the non-zero sampling voltage signal among the second transistor Q2, the third transistor Q3, and the fourth transistor Q4. In this case, the initialization self-test for short-circuit failure detection fails, and the current power-on cycle cannot be terminated, preventing the motor from entering an operating mode for normal control.

[0054] Furthermore, in some implementations, after entering an operating mode in which the motor is controlled normally, the system may continue to detect whether the sampling voltage signals of the ADC input ports u_ADC, v_ADC, and w_ADC of the microprogram control unit MCU are zero, and determine whether an open-circuit fault has occurred in the second transistor Q2, the third transistor Q3, and the fourth transistor Q4 of the drive module.

[0055] The short-circuit fault detection system and method according to the embodiment of the present invention can detect short-circuit faults in phase MOSFET switches, perform an initialization self-test of the detection system, and enter an operating mode for normal motor control without adding circuit costs or software overhead, while simultaneously enabling control of the high-side MOSFET switch. For example, the elements used in the short-circuit fault detection system and method according to the embodiment of the present invention are all general-purpose motor control elements, no further elements are added, the circuit structure is relatively simple, and the manufacturing cost is low. Furthermore, by setting the state of the same port, the short-circuit fault detection system and method can simultaneously perform an initialization self-test and normal motor control, and also have low software overhead.

[0056] Those skilled in the art will understand that the present application is not limited to the specific structures and steps described above and shown in the drawings. For brevity, descriptions of known structures and methods are omitted herein. In the above embodiments, several specific steps are described and shown as examples. However, the methods of the present application are not limited to the specific steps described and shown, and those skilled in the art can make various changes, modifications, and additions to the embodiments of the present application, or change the order of the steps, without departing from the scope of the present application.

[0057] The functional blocks shown in the above structural block diagram may be implemented as hardware, software, firmware, or a combination thereof. When implemented in hardware form, the functional blocks may be, for example, electronic circuits, application-specific integrated circuits (ASICs), appropriate firmware, plug-ins, or functional cards. When implemented in software form, the elements of the present invention are programs or code segments used to perform the required tasks. These programs or code segments may be stored in a machine-readable medium or transmitted via a transmission medium or communication link through data signals carried on a carrier wave. The machine-readable medium may include any medium capable of storing or transmitting information. Examples of machine-readable mediums include electronic circuits, semiconductor memory devices, ROMs, flash memory, erasable ROMs (EROMs), floppy disks, CD-ROMs, optical disks, hard disks, optical fiber media, and radio frequency (RF) links. The code segments may be downloaded via computer networks such as the Internet or an intranet.

[0058] The above disclosures represent only a few specific embodiments of the present application. For the convenience and brevity of explanation, the specific operating processes of the above systems, modules, and units can be understood by those skilled in the art, and are omitted here, as they refer to the corresponding processes in the embodiments of the method. It should also be understood that the scope of protection of the present application is not limited thereto, and those skilled in the art can conceive of various equivalent modifications or substitutions within the technical scope of the disclosures herein, all of which fall within the scope of protection.

Claims

1. A short-circuit fault detection system, A power supply module for supplying power to the detection system, A drive module coupled to the power supply module and the motor, for converting the system voltage provided by the power supply module into a voltage for the motor to operate, A current sampling module coupled to the drive module for sampling the phase current of the motor, A short-circuit fault detection system comprising: a fault detection module coupled to the power supply module and the current sampling module, configured to acquire a phase voltage corresponding to the phase current of the motor, and to perform an initialization self-test of the detection system based on the phase voltage.

2. The detection system according to claim 1, wherein the fault detection module includes a microprogram control unit and is further configured to perform an initialization self-test of the detection system by setting the state of the ports of the microprogram control unit.

3. The detection system according to claim 2, wherein setting the state of the port of the microprogram control unit includes setting the port to either a low-level output state or a high-impedance input state.

4. The detection system according to claim 2 or 3, wherein the fault detection module further includes a drive integrated circuit, and the microprogram control unit is coupled to the drive integrated circuit via a port and configured to control the output state of the drive integrated circuit via the port.

5. The drive integrated circuit includes a charge pump output voltage terminal and a gate drive output voltage terminal, and the output state of the drive integrated circuit is controlled by the ports. When the port is set to a low-level output state, the charge pump output voltage terminal is enabled and the gate drive output voltage terminal is disabled. The detection system according to claim 4, further comprising enabling both the charge pump output voltage terminal and the gate drive output voltage terminal when the port is set to a high impedance input state.

6. The detection system according to claim 2 or 3, wherein the power supply module includes a system power supply and a first transistor, and the fault detection module and the drive module are coupled to the system power supply via the first transistor.

7. The detection system according to claim 6, wherein the fault detection module is further configured to control the on and off states of the first transistor by setting the state of the port of the microprogram control unit.

8. The detection system according to claim 2 or 3, wherein the drive module includes a second transistor, a third transistor, and a fourth transistor, the second transistor, the third transistor, and the fourth transistor are each coupled to different phase lines of the motor.

9. When the port of the microprogram control unit is set to a low-level output state, the second transistor, the third transistor, and the fourth transistor are turned off. The detection system according to claim 8, wherein the second transistor, the third transistor, and the fourth transistor are turned on when the port of the microprogram control unit is set to a high impedance input state.

10. Performing an initialization self-test of the aforementioned detection system is, The detection system according to claim 8, further comprising determining, based on the phase voltage, whether a short-circuit fault has occurred in one or more of the second transistor, the third transistor, and the fourth transistor, using the fault detection module.

11. Determining whether a short-circuit failure has occurred in one or more of the second transistor, the third transistor, and the fourth transistor is: The detection system according to claim 10, further comprising determining that a short-circuit failure has occurred in one or more transistors if the phase voltage of the phase line to which any one or more of the second transistor, the third transistor, and the fourth transistor are coupled is not zero.

12. The detection system according to any one of claims 1 to 3, wherein the current sampling module includes a first resistor, a second resistor, and a third resistor for sampling different phase currents of the motor.

13. The fault detection module further includes a fourth resistor, and the port of the microprogram control unit and the gate drive output voltage terminal of the drive integrated circuit are coupled via the fourth resistor to a chip power supply included in the detection system, the detection system according to claim 5.

14. A short-circuit fault detection method for a short-circuit fault detection system, wherein the detection system includes a power supply module, a drive module, a current sampling module, and a fault detection module, and the detection method is The steps include supplying power to the detection system using the power supply module, The drive module performs the steps of converting the system voltage provided by the power supply module into a voltage for the motor to operate, The steps include sampling the phase current of the motor using the current sampling module, A short-circuit fault detection method comprising the steps of: obtaining a phase voltage corresponding to the phase current of the motor using the fault detection module, and performing an initialization self-test of the detection system based on the phase voltage.

15. The fault detection module includes a microprogram control unit, and the detection method is The process further includes the step of performing an initialization self-test of the detection system by setting the state of the ports of the microprogram control unit using the fault detection module, The detection method according to claim 14, wherein setting the state of the port of the microprogram control unit includes setting the port to one of a low-level output state and a high-impedance input state.

16. The fault detection module further includes a drive integrated circuit, and performs an initialization self-test of the detection system, The detection method according to claim 15, further comprising setting the port of the microprogram control unit to a low-level output state so as to enable the charge pump output voltage terminal of the drive integrated circuit and disable the gate drive output voltage terminal of the drive integrated circuit.

17. Performing an initialization self-test of the aforementioned detection system is, When it is detected that the phase voltage is zero, the charge pump output voltage terminal and the gate drive output voltage terminal of the drive integrated circuit are both enabled, and the ports of the microprogram control unit are set to a high-impedance input state so that the motor enters an operating mode for normal control. The detection method according to claim 16, further comprising determining that a short-circuit fault has occurred if it is detected that the phase voltage is not zero.

18. The power supply module includes a first transistor, and the detection method is The detection method according to claim 15, further comprising controlling the on and off states of the first transistor by setting the state of the port of the microprogram control unit using the fault detection module.

19. The detection method according to claim 15, wherein the drive module includes a second transistor, a third transistor, and a fourth transistor, the second transistor, the third transistor, and the fourth transistor are each coupled to different phase lines of the motor.

20. When the port of the microprogram control unit is set to a low-level output state, the second transistor, the third transistor, and the fourth transistor are turned off. The detection method according to claim 19, wherein when the port of the microprogram control unit is set to a high impedance input state, the second transistor, the third transistor, and the fourth transistor are turned on.

21. Performing an initialization self-test of the aforementioned detection system is, The detection method according to claim 19 or 20, further comprising determining, based on the phase voltage, whether a short-circuit fault has occurred in one or more of the second transistor, the third transistor, and the fourth transistor, using the fault detection module.

22. Determining whether a short-circuit failure has occurred in one or more of the second transistor, the third transistor, and the fourth transistor is: The detection method according to claim 21, further comprising determining that a short-circuit failure has occurred in one or more transistors if the phase voltage of the phase line to which any one or more of the second transistor, the third transistor, and the fourth transistor are coupled is not zero.

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