Fuel injector drive fault detection circuit and method, and electronic device

Abstract

The embodiment of the application provides a kind of fuel injector drive fault detection circuit and method and electronic equipment, it is related to fault detection technical field, fuel injector drive fault detection circuit is by setting high side detection circuit and low side detection circuit respectively output high side detection signal and low side detection signal, by high side pre-drive chip and low side pre-drive chip respectively pre-drive high-low side drive circuit, hardware logic circuit is when any detection signal indicates overcurrent, pre-drive chip is turned off, control unit receives each signal, according to whether high side current sampling signal or low side current sampling signal matches the current working state of fuel injector, and whether high side detection signal or low side detection signal indicates overcurrent in each working state, determine fault detection result.The embodiment of the application avoids the situation of misjudging fault only according to single signal, can adapt to the current characteristic difference of different working stages of fuel injector, improves the accuracy of fault identification.

Description

Technical Field

[0001] This application relates to the field of fault detection technology, and in particular to an injector drive fault detection circuit and method, and electronic equipment. Background Technology

[0002] Fault detection in the fuel injector drive system is crucial for ensuring its reliable operation. Existing technologies often identify faults by detecting the current in each branch of the high and low sides, amplifying it, and comparing it to a threshold. Some existing solutions rely on expensive intelligent power drive chips, which are costly and have limited applicability. Furthermore, each fault requires a separately designed detection signal or circuit, leading to higher costs. Summary of the Invention

[0003] This application provides an injector drive fault detection circuit and method, as well as an electronic device, to alleviate or solve one or more technical problems existing in the prior art.

[0004] In a first aspect, embodiments of this application provide an injector drive fault detection circuit, including: The high-side detection circuit is used to determine whether there is an overcurrent based on the high-side current sampling signal of the high-side drive circuit of the fuel injector, and outputs a high-side detection signal. The low-side detection circuit is used to determine whether there is an overcurrent based on the low-side current sampling signal of the low-side drive circuit of the injector, and outputs a low-side detection signal. A high-side pre-drive chip is used to pre-drive the high-side drive circuit. A low-side pre-drive chip is used to pre-drive the low-side drive circuit. Hardware logic circuitry is used to shut down the high-side pre-drive chip and the low-side pre-drive chip when either the high-side detection signal or the low-side detection signal indicates an overcurrent. The control unit is configured to receive the high-side current sampling signal, the low-side current sampling signal, the high-side detection signal, and the low-side detection signal, and determine the fault detection results of the high-side drive circuit and the low-side drive circuit based on whether the high-side current sampling signal or the low-side current sampling signal matches the current operating state of the injector, and whether the high-side detection signal or the low-side detection signal indicates overcurrent in each of the operating states.

[0005] In some embodiments of this application, the high-side detection circuit includes a high-side hysteresis comparator circuit, the high-side hysteresis comparator circuit includes a high-side comparator, the inverting input terminal of the high-side comparator is connected to the high-side current sampling signal, the high-side current sampling signal is the high-side sampling voltage output across the high-side sampling resistor connected in series in the high-side driving circuit, and the non-inverting input terminal of the high-side comparator is connected to a first voltage divider node, the first voltage divider node is the voltage divider node between the output terminal of the high-side comparator and the first reference voltage; The low-side detection circuit includes a low-side hysteresis comparator circuit, which includes a low-side comparator. The inverting input of the low-side comparator is connected to the low-side current sampling signal, which is the low-side sampling voltage output across the low-side sampling resistor connected in series in the low-side drive circuit. The non-inverting input of the low-side comparator is connected to a second voltage divider node, which is the voltage divider node between the output of the low-side comparator and the second reference voltage.

[0006] In some embodiments of this application, the enable pin of the high-side pre-driver chip is active high and inactive low; the enable pin of the low-side pre-driver chip is active high and inactive low. The hardware logic circuit includes: The first diode has its anode connected to the enable terminal of the high-side pre-drive chip and its cathode connected to the high-side detection signal. The second diode has its anode connected to the enable terminal of the high-side pre-drive chip and its cathode connected to the low-side detection signal. The third diode has its anode connected to the enable terminal of the low-side pre-drive chip and its cathode connected to the high-side detection signal. The fourth diode has its anode connected to the enable terminal of the low-side pre-drive chip and its cathode connected to the low-side detection signal.

[0007] In some embodiments of this application, there are multiple injectors; the low-side drive circuit includes multiple low-side drive sub-circuits that drive the multiple injectors in a one-to-one correspondence; there are multiple low-side pre-drive chips, each of which is used to pre-drive each of the low-side drive sub-circuits in a one-to-one correspondence; the low-side current sampling signal is obtained by sampling the total current of the multiple low-side drive sub-circuits. The control unit is configured to, when the operating state is in the peak stage and the maintenance stage, if it is determined that the low-side detection signal indicates an overcurrent, control the high-side pre-drive chip to turn off, and poll and turn on each of the low-side pre-drive chips, and determine the fault detection result based on the low-side detection signal when each of the low-side drive sub-circuits is turned on.

[0008] In some embodiments of this application, the control unit is further configured to, after polling and turning on each of the low-side pre-driver chips: If it is determined that the low-side detection signal indicates overcurrent when each of the low-side driving sub-circuits is turned on, then the fault detection result is determined to be a short circuit fault of the high-side driving circuit to the power supply. If it is determined that the low-side detection signal indicates no current flow when each of the low-side driving sub-circuits is turned on, then the fault detection result is determined to be a short circuit fault between the high-side driving circuit and the low-side driving circuit. If it is determined that the low-side detection signal indicates overcurrent when part of the low-side driver sub-circuit is turned on, then the fault detection result is determined to be a short circuit fault of the corresponding low-side driver sub-circuit to the power supply.

[0009] In some embodiments of this application, the high-side drive circuit includes a high-voltage high-side drive sub-circuit for driving a high-voltage power supply to supply power to a plurality of injectors and a low-voltage high-side drive sub-circuit for driving a low-voltage power supply to supply power to a plurality of injectors; the high-side pre-drive chip includes a high-voltage high-side pre-drive chip for pre-drives the high-voltage high-side drive sub-circuit and a low-voltage high-side pre-drive chip for pre-drives the low-voltage high-side drive sub-circuit; the high-side current sampling signal is obtained by sampling the current of the branch where the low-voltage high-side drive sub-circuit is located; The control unit is configured to, when the operating state is the maintenance phase, determine the fault detection result as a short circuit to ground fault if it is determined that the high-side detection signal indicates an overcurrent, and when the operating state is the peak phase, determine the fault detection result as a short circuit to ground fault based on the fact that the change trend of the low-side current sampling signal over time does not conform to the preset current change trend of the peak phase.

[0010] In some embodiments of this application, the control unit is further configured to: When the working state is that the injector is not driven after power-on, the fault detection result is determined to be a short circuit to ground fault based on the ratio of the high-side current sampling signal to the low-voltage power supply being less than a preset threshold. When the operating state is that the low-side drive circuit is turned on and the high-side drive circuit is turned off, the fault detection result is determined to be a power supply short circuit fault based on the ratio of the high-side current sampling signal to the low-voltage power supply being greater than the preset threshold.

[0011] Secondly, embodiments of this application provide a method for detecting injector drive faults, the method being applied to an injector drive fault detection circuit provided in any of the technical solutions of the first aspect, the method comprising: Receives high-side current sampling signal, low-side current sampling signal, high-side detection signal and low-side detection signal; Based on whether the high-side current sampling signal or the low-side current sampling signal matches the current operating state of the injector, and whether the high-side detection signal or the low-side detection signal indicates overcurrent, the fault detection results of the high-side drive circuit and the low-side drive circuit are determined.

[0012] In some embodiments of this application, determining the fault detection results of the high-side drive circuit and the low-side drive circuit includes: When the working state is that the injector is not driven after power-on, the fault detection result is determined to be a short circuit to ground fault based on the ratio of the high-side current sampling signal to the low-voltage power supply being less than a preset threshold. When the working state is that the low-side drive circuit is turned on and the high-side drive circuit is turned off, the fault detection result is determined to be a power supply short circuit fault based on the ratio of the high-side current sampling signal to the low-voltage power supply being greater than the preset threshold. When the operating state is in the maintenance phase, if it is determined that the high-side detection signal indicates an overcurrent, then the fault detection result is determined to be a short-circuit fault to ground. When the operating state is at its peak, if the trend of the low-side current sampling signal over time does not conform to the preset current trend of the peak stage, the fault detection result is determined to be a short-circuit fault to ground. When the operating state is in the peak phase and the maintenance phase, if it is determined that the low-side detection signal indicates an overcurrent, the high-side pre-driver chip is controlled to be turned off, and each of the low-side pre-driver chips is polled to be turned on: If it is determined that the low-side detection signal indicates overcurrent when each of the low-side driving sub-circuits is turned on, then the fault detection result is determined to be a short circuit fault of the high-side driving circuit to the power supply. If it is determined that the low-side detection signal indicates no current flow when each of the low-side driving sub-circuits is turned on, then the fault detection result is determined to be a short circuit fault between the high-side driving circuit and the low-side driving circuit. If it is determined that the low-side detection signal indicates overcurrent when part of the low-side driver sub-circuit is turned on, then the fault detection result is determined to be a short circuit fault of the corresponding low-side driver sub-circuit to the power supply.

[0013] Thirdly, embodiments of this application provide an electronic device, including a memory, a processor, and a computer program stored in the memory, wherein the processor implements any of the methods of embodiments of this application when executing the computer program.

[0014] Fourthly, embodiments of this application provide a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the method of any one of the embodiments of this application.

[0015] Fifthly, embodiments of this application provide a computer program product, including a computer program, which, when executed by a processor, implements any of the methods described in the embodiments of this application.

[0016] Based on any of the above technical solutions, this application has at least the following beneficial effects or advantages: This embodiment of the application sets up a high-side detection circuit and a low-side detection circuit to output high-side detection signals and low-side detection signals respectively. The high-side pre-drive chip and the low-side pre-drive chip pre-drive the high-side and low-side drive circuits respectively. The hardware logic circuit shuts down the pre-drive chip when any detection signal indicates overcurrent. The control unit receives each signal. Considering the differences in current characteristics under different operating states, by determining whether the current sampling signals under different operating states match, and by determining whether the detection signals under different operating states are overcurrent, the application avoids the situation of misjudging the fault based on a single signal. It can adapt to the differences in current characteristics of different operating stages of the injector and improve the accuracy of fault identification.

[0017] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application, it can be implemented according to the contents of the specification. In order to make the above and other objects, features and advantages of this application more obvious and understandable, specific embodiments of this application are given below. Attached Figure Description

[0018] In the accompanying drawings, unless otherwise specified, the same reference numerals throughout the various drawings denote the same or similar parts or elements. These drawings are not necessarily drawn to scale. It should be understood that these drawings depict only some embodiments according to this application and should not be construed as limiting the scope of this application.

[0019] Figure 1 A schematic block diagram of an injector drive fault detection circuit provided in an embodiment of this application is shown; Figure 2 A schematic diagram of an injector drive fault detection circuit provided in an embodiment of this application is shown; Figure 3 A schematic diagram of the current waveform of an injector drive fault detection circuit provided in an embodiment of this application is shown. Figure 4 The flowchart of an injector drive fault detection method provided in an embodiment of this application is shown. Figure 1 ; Figure 5The flowchart of an injector drive fault detection method provided in an embodiment of this application is shown. Figure 2 ; Figure 6 A block diagram of an electronic device provided in an embodiment of this application is shown.

[0020] The following are the corresponding contents of some of the figure labels in the attached figures: 21. Fuel Injection Drive Unit; 22. Fuel Injector Drive Fault Detection Circuit; 211. Fuel Injector; 221. MCU; 222. Fuel Injection Microcontroller; 223. High-Side Pre-Driver Chip; 224. Low-Side Pre-Driver Chip; U1: High-Side Comparator; U2: High-Side Amplifier; U3: Low-Side Comparator; U4: Low-Side Amplifier; V REF Reference voltage, U BAT Battery voltage, U BOOST : Boost voltage. Detailed Implementation

[0021] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the concept or scope of this application. Therefore, the drawings and description are considered to be exemplary in nature and not restrictive.

[0022] To facilitate understanding of the technical solutions of the embodiments of this application, the relevant technologies of the embodiments of this application are described below. The following related technologies are optional solutions and can be arbitrarily combined with the technical solutions of the embodiments of this application, all of which fall within the protection scope of the embodiments of this application. It should be noted that the application scenarios or application examples provided in this application are for ease of understanding, and the embodiments of this application do not specifically limit the application of the technical solutions.

[0023] The following explains some of the technical terms that appear in the embodiments of this application.

[0024] MCU: Microcontroller Unit, also known as a single-chip microcomputer, or microcontroller.

[0025] High Side / Low Side: Used to define the connection location of components or circuits. The difference between high side and low side lies in whether the component or circuit is located between the power supply and the load (such as a fuel injector) or between the load and ground. If the component or circuit is located between the power supply and the load, it is a high side; if the component or circuit is located between the load and ground, it is a low side.

[0026] High-side / low-side pre-driver chip: This is an integrated circuit specifically designed to drive power switching devices (such as MOSFETs). Its main function is to convert the low-voltage / weak-current control signal output by the main control chip into a high-voltage / high-current drive signal to achieve power output.

[0027] MOSFET: Metal-Oxide-Semiconductor Field-Effect Transistor, is a voltage-controlled semiconductor device mainly used in amplifier circuits or switching circuits, characterized by high input impedance and low power consumption.

[0028] Amplifier: An operational amplifier is a high-gain, DC-coupled electronic voltage amplifier with two input terminals (non-inverting and inverting) and one output terminal. Its basic function is to amplify the voltage difference between the two input terminals and output it with extremely high gain.

[0029] Comparator: A voltage comparator is an electronic circuit used to compare the magnitudes of two voltage signals and output a high or low level digital signal based on the comparison result.

[0030] Peak phase: also known as the peak phase, is the initial stage of injector drive, achieved through high-side boost voltage (high voltage U). BOOST The branch circuit provides a high-voltage, high-current supply to quickly open the injector valve.

[0031] Maintenance Phase: Also known as the Hold phase, this is the phase following the injector drive, where the high-side UBAT voltage (low-voltage U) is switched to. BAT The branch circuit provides a low-voltage, small current to keep the injector valve continuously open, thus reducing power consumption.

[0032] The technical solution of this application and how it solves the aforementioned technical problems are described in detail below with specific embodiments. The listed specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0033] Figure 1 An injector drive fault detection circuit provided in this application embodiment includes: The high-side detection circuit 101 is used to determine whether there is an overcurrent based on the high-side current sampling signal of the high-side drive circuit 105 of the injector, and outputs a high-side detection signal. The low-side detection circuit 102 is used to determine whether there is an overcurrent based on the low-side current sampling signal of the low-side drive circuit 106 of the injector, and outputs a low-side detection signal. High-side pre-driver chip 223 is used to pre-drive the high-side drive circuit; Low-side pre-driver chip 224 is used to pre-drive the low-side drive circuit. Hardware logic circuit 103 is used to turn off the high-side pre-drive chip and the low-side pre-drive chip when either the high-side detection signal or the low-side detection signal indicates an overcurrent. The control unit 104 is used to receive high-side current sampling signals, low-side current sampling signals, high-side detection signals and low-side detection signals, and determine the fault detection results of the high-side drive circuit and the low-side drive circuit based on whether the high-side current sampling signal or the low-side current sampling signal matches the current working state of the injector, and whether the high-side detection signal or the low-side detection signal indicates overcurrent in each working state.

[0034] The high-side detection circuit 101 is used to sample the current of the high-side drive circuit 105. In some embodiments, the current can be acquired by a high-side sampling resistor connected in series in the high-side drive circuit 105. After obtaining the high-side sampling voltage across the high-side sampling resistor, the high-side sampling voltage is compared with an overcurrent threshold to determine whether there is an overcurrent, and a high-side detection signal is output. Similarly, the low-side detection circuit 102 is used to sample the current of the low-side drive circuit 106.

[0035] The high-side pre-drive chip 223 can receive instructions from the control unit 104 to convert the weak current control signal into a high current drive signal, thereby driving the power devices in the high-side drive circuit 1. The low-side pre-drive chip 224 has the same function as the high-side pre-drive chip 223 and is used to drive the low-side drive circuit 106.

[0036] The hardware logic circuit 103 is a fixed logic circuit directly constructed from discrete electronic components (such as diodes, resistors, capacitors, transistors, comparators, etc.). Its function is realized through the physical connection relationship of the components, without the need for software program intervention. In some embodiments, a wired-AND logic structure composed of diodes can be used. When either the high-side detection signal or the low-side detection signal is in an overcurrent state, the enable terminal voltage of the pre-driver chip is immediately pulled down, and the pre-driver chip is turned off, achieving fast hardware protection.

[0037] The control unit 104 receives each current sampling signal and detection signal in real time. Combined with the current peak stage or maintenance stage of the injector, it determines whether the sampling signal matches the current characteristics of the corresponding stage. At the same time, based on the overcurrent state of the detection signal, it comprehensively determines the fault type of the high-side drive circuit 105 and the low-side drive circuit 106.

[0038] This embodiment of the application sets up high-side detection circuits and low-side detection circuits to output high-side detection signals and low-side detection signals respectively. High-side pre-drive chips and low-side pre-drive chips pre-drive the high and low-side drive circuits respectively. The hardware logic circuit shuts down the pre-drive chip when any detection signal indicates overcurrent. The control unit receives each signal and, considering the differences in current characteristics under different operating states, determines whether the current sampling signals under different operating states match, and determines whether the detection signal under different operating states indicates overcurrent. This avoids misjudging faults based on a single signal, adapting to the differences in current characteristics of the injector at different operating stages and improving the accuracy of fault identification. Furthermore, the hardware logic circuit quickly shuts down the high and low-side pre-drive chips when any detection signal indicates overcurrent, thereby protecting against component burnout. The hardware logic circuit is implemented using discrete components, reducing reliance on expensive intelligent drive chips.

[0039] Optionally, the high-side detection circuit may include a high-side hysteresis comparator circuit, and the low-side detection circuit may include a low-side hysteresis comparator circuit.

[0040] In some embodiments of this application, the high-side detection circuit includes a high-side hysteresis comparator circuit, which includes a high-side comparator. The inverting input of the high-side comparator is connected to a high-side current sampling signal, which is the high-side sampling voltage output across the high-side sampling resistor connected in series in the high-side driving circuit. The non-inverting input of the high-side comparator is connected to a first voltage divider node, which is the voltage divider node between the output of the high-side comparator and the first reference voltage.

[0041] refer to Figure 2 The high-side hysteresis comparator circuit includes a high-side comparator U1, which is a voltage comparator. The inverting input terminal "-" of high-side comparator U1 is connected to the high-side current sampling signal, i.e., the high-side voltage amplification signal output by high-side amplifier U2. This high-side voltage amplification signal is obtained by amplifying the high-side sampling voltage sampled across the high-side sampling resistor R1. The non-inverting input terminal "+" of high-side comparator U1 is connected to the first voltage divider node 225. The output terminal of high-side comparator U1 is connected to the first reference voltage V. REF The voltage after being divided by resistors R9 and R10 is connected to the non-inverting input "+" of the high-side comparator U1. (Reference) Figure 2 The overcurrent detection threshold at the first voltage divider node 225 is I. fault : I fault =(V OUT_high *R10+VREF*R9) / (R9+R10)*R1*K1 Wherein, the amplification factor of the high-side amplifier U2 is K1, V OUT_high This is the output voltage when the output of the high-side comparator U1 is high.

[0042] Similarly, in some embodiments of this application, the low-side detection circuit includes a low-side hysteresis comparator circuit, which includes a low-side comparator. The inverting input of the low-side comparator is connected to a low-side current sampling signal, which is the low-side sampling voltage output across the low-side sampling resistor connected in series in the low-side drive circuit. The non-inverting input of the low-side comparator is connected to a second voltage divider node, which is the voltage divider node between the output of the low-side comparator and the second reference voltage.

[0043] refer to Figure 2 The low-side hysteresis comparator circuit includes a low-side comparator U3, which is a voltage comparator. The inverting input "-" of low-side comparator U3 is connected to the low-side current sampling signal, i.e., the low-side voltage amplification signal output by low-side amplifier U4. This low-side voltage amplification signal is obtained by amplifying the low-side sampling voltage sampled across low-side sampling resistor R6. The non-inverting input "+" of low-side comparator U3 is connected to the second voltage divider node 226. The output of low-side comparator U3 is connected to the second reference voltage V. REF The voltage after being divided by voltage divider resistors R7 and R8 is connected to the non-inverting input "+" of the low-side comparator U3.

[0044] Employing a hysteresis comparator circuit effectively suppresses false alarms caused by voltage fluctuations. The hysteresis comparator circuit introduces positive feedback through a feedback loop connected to the comparator output, dividing the comparator's threshold voltage into upper and lower limits. This avoids repeated output jumps when the input signal fluctuates slightly, improving the accuracy of fault detection. Converting the current signal into a voltage signal for comparison using a sampling resistor is simple and reliable, reducing circuit design complexity and cost.

[0045] In some embodiments of this application, the enable pin of the high-side pre-driver chip is active high and inactive low; the enable pin of the low-side pre-driver chip is active high and inactive low. (See reference) Figure 2 The hardware logic circuit includes: The anode of the first diode D7 is connected to the enable terminal of the high-side pre-drive chip 223, and the cathode is connected to the high-side detection signal. The anode of the second diode D8 is connected to the enable terminal of the high-side pre-drive chip 223, and the cathode is connected to the low-side detection signal. The third diode D9 has its anode connected to the enable terminal of the low-side pre-driver chip 224, and its cathode connected to the high-side detection signal. The fourth diode D10 has its anode connected to the enable terminal of the low-side pre-drive chip 224, and its cathode connected to the low-side detection signal.

[0046] When either the high-side detection signal or the low-side detection signal is low (indicating overcurrent), the corresponding diode is forward-biased, pulling down the enable voltage of all pre-driver chips, causing the pre-driver chips to fail and thus shutting down the high-side and low-side drive circuits. For example, when the low-side detection signal becomes low due to overcurrent, the second diode D8 and the fourth diode D10 are forward-biased, pulling down the enable voltage of both the high-side pre-driver chip 223 and the low-side pre-driver chip 224, causing both pre-driver chips to stop working and the high-side and low-side drive circuits to disconnect.

[0047] This application embodiment utilizes the unidirectional conduction characteristic of diodes to construct hardware logic circuits, which can achieve rapid shutdown in case of overcurrent faults without complex digital circuits. It has a fast response speed, simple hardware structure and low cost, and can effectively avoid component damage caused by the expansion of faults.

[0048] In some embodiments of this application, there are multiple injectors; the low-side drive circuit includes multiple low-side drive sub-circuits that drive the multiple injectors one-to-one; there are multiple low-side pre-drive chips, each low-side pre-drive chip is used to pre-drive each low-side drive sub-circuit one-to-one; the low-side current sampling signal is obtained by sampling the total current of the multiple low-side drive sub-circuits.

[0049] Figure 2 The example shows the case of three injectors 211; correspondingly, there are also three low-side pre-drive chips 224, but... Figure 2 The diagram simplifies the representation of a low-side pre-driver chip. The low-side drive circuit includes three low-side drive sub-circuits: low-side drive transistors Q3, Q4, and Q5. When a low-side drive transistor is turned on, its corresponding injector is connected to ground. The output of each low-side pre-driver chip is connected to the gate of its respective low-side drive transistor, and each chip controls the on / off state of its connected transistor. The input of each chip is connected to the anodes of the third and fourth diodes, thus providing hardware protection. The low-side sampling resistor R6 samples the total current of all low-side drive sub-circuits; therefore, any problem in the branch containing any injector will be reflected in the low-side current sampling signal.

[0050] refer to Figure 2The control unit is a 222 microcontroller. The control unit is connected separately to each low-side pre-driver chip, and can control the on / off state of each chip individually. It can be understood that all low-side pre-driver chips are uniformly connected to the anodes of the second and fourth diodes; therefore, if either the second or fourth diode is conducting, all low-side pre-driver chips will fail and shut down. The control unit, however, can independently control whether each low-side pre-driver chip fails and shuts down. During peak and maintenance phases, if the control unit determines that the low-side detection signal indicates an overcurrent, it controls the high-side pre-driver chip to shut down and polls each low-side pre-driver chip to turn on. Based on the low-side detection signals when each low-side driver sub-circuit is turned on, the fault detection result is determined.

[0051] This application embodiment uses a polling method to activate the low-side drive sub-circuit, which can accurately locate the specific branch where the fault occurs, achieving refined fault detection. Multiple low-side drive sub-circuits share the total current sampling signal, which can reduce the number of sampling resistors and reduce the circuit board layout area and cost.

[0052] In some embodiments of this application, the control unit is further configured to: after polling and turning on each low-side pre-driver chip: If it is determined that the low-side detection signal indicates overcurrent when each low-side drive sub-circuit is turned on, then the fault detection result is determined to be a short circuit fault of the high-side drive circuit to the power supply. If it is determined that the low-side detection signal indicates no current flow when each low-side drive sub-circuit is turned on, then the fault detection result is determined to be a short circuit fault between the high-side drive circuit and the low-side drive circuit. If it is determined that the low-side detection signal indicates overcurrent when a portion of the low-side driver sub-circuit is turned on, then the fault detection result is determined to be a short circuit fault in the power supply of the corresponding low-side driver sub-circuit.

[0053] After the control unit completes the polling and activation of each low-side pre-driver chip, it determines the fault type based on the different low-side detection signal feedback. If all low-side driver sub-circuits are activated and the low-side detection signal indicates overcurrent, it means the high-side driver circuit is directly short-circuited to the power supply. Regardless of which low-side sub-circuit is activated, an overcurrent loop will be formed, thus the fault is determined to be a high-side driver circuit short-circuit to the power supply. If all low-side driver sub-circuits are activated and the low-side detection signal indicates no current, it means there is a mutual short between the high and low sides but no power supply connection, resulting in no overcurrent. This is determined to be a high-low side mutual short fault. If only some low-side driver sub-circuits are activated and the low-side detection signal indicates overcurrent, it means that part of the sub-circuit is directly short-circuited to the power supply, thus the fault is determined to be a corresponding low-side driver sub-circuit short-circuit to the power supply. For example, when polling and activating three low-side driver sub-circuits, if the low-side detection signal indicates overcurrent when the first two are activated but not when the third is activated, then the first two low-side driver sub-circuits are determined to have a short-circuit to the power supply fault.

[0054] Based on the feedback results of polling detection, the embodiments of this application can accurately distinguish three fault types: high-side to power supply short circuit, high-low side mutual short circuit, and low-side to power supply short circuit. The fault identification accuracy is high, providing a clear direction for subsequent fault diagnosis and repair.

[0055] In some embodiments of this application, the high-side drive circuit includes a high-voltage high-side drive sub-circuit for driving a high-voltage power supply to supply power to multiple injectors and a low-voltage high-side drive sub-circuit for driving a low-voltage power supply to supply power to multiple injectors; the high-side pre-drive chip includes a high-voltage high-side pre-drive chip for pre-drive the high-voltage high-side drive sub-circuit and a low-voltage high-side pre-drive chip for pre-drive the low-voltage high-side drive sub-circuit; the high-side current sampling signal is obtained by sampling the current of the branch where the low-voltage high-side drive sub-circuit is located; the control unit is used to determine the fault detection result as a short circuit to ground fault if the high-side detection signal indicates an overcurrent when the working state is in the maintenance stage, and to determine the fault detection result as a short circuit to ground fault when the working state is in the peak stage, based on the fact that the change trend of the low-side current sampling signal over time does not conform to the preset current change trend of the peak stage.

[0056] refer to Figure 2 The high-voltage high-side drive sub-circuit includes a high-side high-voltage transistor Q1, and the low-voltage high-side drive sub-circuit includes a high-side low-voltage transistor Q2. The high-voltage power supply is a boost voltage U. BOOST The low-voltage power supply is the battery voltage U. BAT The high-voltage power supply can be obtained by boosting the voltage of the low-voltage power supply. The high-voltage high-side drive sub-circuit is used to drive the high-voltage power supply to supply power to the injector, adapting to the high current demand during the peak stage; the low-voltage high-side drive sub-circuit is used to drive the low-voltage power supply, adapting to the low current demand during the maintenance stage.

[0057] Correspondingly, there are two high-side pre-drive chips: a high-voltage high-side pre-drive chip and a low-voltage high-side pre-drive chip. Figure 2 Only one high-side pre-driver chip is shown in the simplified diagram. Two high-side pre-driver chips pre-drive their respective high-side driver sub-circuits. The high-side current sampling signal is obtained through the sampling resistor R1 of the branch containing the low-voltage high-side driver sub-circuit, mainly monitoring the current during the sustain phase.

[0058] When the control unit determines that the operating state is in the maintenance phase, if the high-side detection signal indicates overcurrent, it means that there is a short circuit to ground in the low-voltage high-side drive branch, and it is determined to be a short circuit to ground fault. When the operating state is in the peak phase, the control unit monitors the change trend of the low-side current sampling signal over time. If it does not conform to the preset change trend of the peak phase current increasing proportionally with time, it is determined to be a short circuit to ground fault.

[0059] refer to Figure 3This is a schematic diagram of an example current change curve. The horizontal axis represents time, and the vertical axis represents current. During the peak stage, the high-voltage power supply provides power, and the current changes with time in a straight line with a certain slope until it reaches the highest peak current. During the maintenance stage, the current gradually decreases and tends to stabilize at the maintenance current.

[0060] In this embodiment, only one sampling resistor is set on the high side to collect the current in the low-voltage high-side drive circuit, while the high-voltage high-side drive circuit determines the fault by whether the high-side current sampling signal during the boost process conforms to the boost trend. Differentiated short-circuit fault detection logic to ground is designed for the circuit characteristics of different operating stages, covering the entire peak and maintenance stages, providing comprehensive and accurate detection. Fault judgment is achieved using existing sampling signals without the need for additional detection devices, thus controlling costs.

[0061] In some embodiments of this application, the control unit is further configured to: When the working state is that the injector is not driven after power-on, the fault detection result is determined to be a short circuit to ground fault based on the ratio of the high-side current sampling signal to the low-voltage power supply being less than a preset threshold. When the low-side drive circuit is on and the high-side drive circuit is off, the fault detection result is determined to be a short circuit fault in the power supply based on the ratio of the high-side current sampling signal to the low-voltage power supply being greater than a preset threshold.

[0062] In addition to fault detection during the drive phase, the control unit also covers fault detection during power-on but not driven and under specific switching states. When the injector is not driven after power-on, the high-side detection circuit still monitors the high-side voltage and calculates the ratio of the high-side current sampling signal to the low-voltage power supply voltage. If this ratio is less than a preset threshold, it indicates a short circuit to ground in the high-side drive circuit, resulting in an abnormally low sampling signal, and is determined to be a short circuit to ground fault. When the low-side drive circuit is on and the high-side drive circuit is off, if the ratio of the high-side current sampling signal to the low-voltage power supply voltage is greater than a preset threshold, it indicates a short circuit between the high-side drive circuit and the power supply, resulting in an abnormally high sampling signal, and is determined to be a short circuit to the power supply fault.

[0063] refer to Figure 2 For example, taking the high side as an example, the preset threshold is the high side current sampling signal (the high side acquisition voltage obtained by sampling across the high side R1) and the low-voltage power supply U. BAT The ratio K2 is slightly larger than the ratio when short-circuited to ground, but much smaller than 1 / 2 (1 / 2 is the normal voltage ratio when the high side is not driven). The low side is similar and will not be described further.

[0064] The embodiments of this application expand the coverage of fault detection, enabling pre-detection of faults during the power-on phase and under specific switching states, thus discovering potential faults in advance, preventing the faults from escalating after the driver is turned on, and further improving the reliability and safety of the system.

[0065] refer to Figure 2 A specific example of an injector drive fault detection circuit is provided. Figure 2 It includes an injection drive unit 21 and an injector drive fault detection circuit 22.

[0066] refer to Figure 2 In the fuel injection drive unit 21, U BAT and U BOOST The power supply is connected to the high-side low-voltage transistor Q2 and the high-side high-voltage transistor Q1, respectively. The output terminals of Q1 and Q2 are connected to the high-side input terminal of the injector 211. The high-side sampling resistor R1 is connected in series in the Q1 branch. The high-side sampling voltage output by R1 is amplified by the high-side amplifier U2 and used as the high-side current sampling signal. BAT The high-side terminal of injector 211 is connected via diode D11 and voltage divider resistors R2, R3, R4, and R5. The low-side terminal of injector 211 is connected to three low-side drive transistors Q3, Q4, and Q5. The outputs of these transistors are connected in series with low-side sampling resistor R6 and then grounded. The low-side sampling voltage output by R6 is amplified by low-side amplifier U4 and used as the low-side current sampling signal.

[0067] refer to Figure 2 In the injector drive fault detection circuit 22, the inverting input of the high-side comparator U1 is connected to the high-side voltage amplification signal output by U2, and the non-inverting input is connected to the first voltage divider node 225 formed by its output and the first reference voltage VREF. The first voltage divider node 225 is between voltage divider resistors R9 and R10, and U1 outputs a high-side detection signal. The inverting input of the low-side comparator U3 is connected to the low-side voltage amplification signal output by U4, and the non-inverting input is connected to the second voltage divider node 226 formed by its output and the second reference voltage VREF. The second voltage divider node 226 is between voltage divider resistors R7 and R8, and U3 outputs a low-side detection signal.

[0068] refer to Figure 2 The hardware logic circuit includes diodes D7, D8, D9, and D10. The connection methods between the hardware logic circuit and the high-side pre-driver chip 223 and the low-side pre-driver chip 224 are not detailed here. The microcontroller 222 acts as the control unit. One input terminal receives the drive control signal sent by the MCU 221. Based on the drive control signal, it specifically controls the output signal. The output terminal is connected to the high-side detection signal, the low-side detection signal, the high-side pre-driver chip 223, and the low-side pre-driver chip 224, respectively. Simultaneously, the corresponding terminals of Q3, Q4, and Q5 are also connected to the U-band via diodes D4, D5, and D6, respectively. BOOST And the ground.

[0069] It is understood that the injector drive fault detection circuit and injector drive fault detection method provided in the embodiments of this application are based on the same inventive concept. The implementation methods and technical effects not described in detail in one embodiment can be referred to the content of another embodiment, and the same parts will not be described again.

[0070] This application provides a method for detecting injector drive faults. This method is applied to the injector drive fault detection circuit provided in this application embodiment. (Refer to...) Figure 4 The method includes: Step A1: Receive the high-side current sampling signal, the low-side current sampling signal, the high-side detection signal, and the low-side detection signal; Step A2: Determine the fault detection results of the high-side drive circuit and the low-side drive circuit based on whether the high-side current sampling signal or the low-side current sampling signal matches the current working state of the injector and whether the high-side detection signal or the low-side detection signal indicates overcurrent.

[0071] The embodiments of this application are based on a hardware structure design of the circuit, which can cover fault detection under all working conditions. By combining the sampling signal and the detection signal for comprehensive judgment, the comprehensiveness and accuracy of fault detection are improved, and it can adapt to the identification needs of various fault types.

[0072] Furthermore, in some embodiments of this application, step A2, determining the fault detection results of the high-side drive circuit and the low-side drive circuit, includes: Step B1: When the working state is that the injector is not driven after power-on, the fault detection result is determined to be a short circuit to ground fault based on the ratio of the high-side current sampling signal to the low-voltage power supply being less than a preset threshold. Step B2: When the working state is that the low-side drive circuit is turned on and the high-side drive circuit is turned off, the fault detection result is determined to be a short circuit fault in the power supply based on the ratio of the high-side current sampling signal to the low-voltage power supply being greater than a preset threshold. Step B3: If the high-side detection signal indicates overcurrent when the working state is in the maintenance phase, then the fault detection result is determined to be a short circuit to ground fault. Step B4: When the working state is in the peak stage, the fault detection result is determined to be a short circuit to ground fault because the trend of the low-side current sampling signal over time does not conform to the preset current trend of the peak stage. Step B51: When the operating state is in the peak phase and maintenance phase, if it is determined that the low-side detection signal indicates an overcurrent, then the high-side pre-driver chip is turned off, and each low-side pre-driver chip is polled and turned on. Step B52: If it is determined that the low-side detection signal indicates overcurrent when each low-side drive sub-circuit is turned on, then the fault detection result is determined to be a short circuit fault of the high-side drive circuit to the power supply. Step B53: If it is determined that the low-side detection signal indicates no current flow when each low-side drive sub-circuit is turned on, then the fault detection result is determined to be a short circuit fault between the high-side drive circuit and the low-side drive circuit. Step B54: If it is determined that the low-side detection signal indicates overcurrent when a portion of the low-side driver sub-circuit is turned on, then the fault detection result is determined to be a short circuit fault in the power supply of the corresponding low-side driver sub-circuit.

[0073] The embodiments of this application are designed with differentiated judgment logic for different working states and fault types, which can accurately identify various short-circuit faults, improve the reliability and safety of the system, and at the same time, it does not require complex detection algorithms, making it simple and efficient.

[0074] refer to Figure 5 This is a specific example of an injector drive fault detection method in Embodiment 1 of this application.

[0075] After the process begins, it first checks if the power is on. If so, it further checks if the fuel injector is driven. If the fuel injector is not driven, the system is in a power-on but not fuel injector-driven operating state. At this time, it calculates the high-side current sampling signal (high-side voltage) and the low-voltage power supply U. BAT If the ratio of the high-side current sampling signal to the low-voltage power supply is less than the preset threshold K2, the fault detection result is determined to be a short circuit to ground. If fuel injection has been activated, it is determined whether the low-side drive circuit is activated but the high-side drive circuit is not. If so, the ratio of the high-side current sampling signal to the low-voltage power supply is calculated. If the ratio is greater than the preset threshold K2, the fault detection result is determined to be a short circuit to power supply. If not, it is determined whether the peak stage has been entered.

[0076] During the peak phase, the trend of the low-side current sampling signal over time is monitored to determine whether the low-side current sampling signal (low-side current) reaches the preset current change trend corresponding to the current value at the current moment. If it does not meet the preset current change trend of the peak phase, the fault detection result is determined to be a short circuit to ground fault. At the same time, it is also determined whether the low-side detection signal (low-side signal) is pulled low. If it is pulled low, the high-side drive is cut off and each low-side pre-drive chip is polled and enabled, and the polling fault judgment process is entered.

[0077] After the peak phase ends, the maintenance phase begins. During this phase, it is determined whether the high-side detection signal (high-side signal) has been pulled low. If the high-side detection signal indicates an overcurrent, the fault detection result is determined to be a short circuit to ground. At the same time, it is also determined whether the low-side signal has been pulled low. If it has been pulled low, the high-side drive is cut off and the low-side pre-drive chip is polled and enabled, repeating the peak phase process of cutting off the high-side drive and polling to enable the low-side pre-drive chip, thus entering the polling fault determination process.

[0078] The polling fault determination process includes: determining whether all circuits are pulled low; if so, the fault detection result is determined to be a short circuit fault between the high-side drive circuit and the power supply; if not, determining whether all circuits are not pulled low; if so, the fault detection result is determined to be a short circuit fault between the high-side drive circuit and the low-side drive circuit; if not, determining whether some circuits are pulled low; if so, the fault detection result is determined to be a short circuit fault between the corresponding low-side drive sub-circuit and the power supply.

[0079] In this embodiment, after power-on, if the injectors need to be started, the non-driven state is first checked. If no fault is found, the low-side drive circuit is activated. After another fault is detected, the high-voltage high-side drive circuit is activated to enter the peak stage of high-voltage power supply. If no fault is found, the high-voltage high-side drive circuit is deactivated, and the low-voltage high-side drive circuit is activated to enter the maintenance stage of low-voltage power supply. During this process, if a fault is detected at any stage, an alarm can be issued to prompt maintenance and inspection. In some cases, the system can also be shut down. For example, if only some injectors are faulty, the system can remain running and only issue a warning; if all injectors are faulty, the system will be shut down.

[0080] Figure 6 This is a block diagram of an electronic device used to implement embodiments of this application. For example... Figure 6 As shown, the electronic device includes a memory 601 and a processor 602. The memory 601 stores a computer program that can run on the processor 602. When the processor 602 executes the computer program, it implements the method described in the above embodiments. The number of memories 601 and processors 602 can be one or more. In a specific implementation, the electronic device may also include a communication interface 603 for communicating with external devices and exchanging data.

[0081] In practical implementation, if the memory 601, processor 602, and communication interface 603 are implemented independently, they can be interconnected via a bus to communicate with each other. This bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. This bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 6 The bus is represented by a single thick line, but this does not mean that there is only one bus or one type of bus.

[0082] Optionally, in a specific implementation, if the memory 601, processor 602 and communication interface 603 are integrated on a single chip, the memory 601, processor 602 and communication interface 603 can communicate with each other through an internal interface.

[0083] This application provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the method provided in this application.

[0084] This application provides a computer program product, including a computer program that, when executed by a processor, implements the method provided in this application.

[0085] This application also provides a chip including a processor for calling and executing instructions stored in a memory, causing a communication device with the chip installed to perform the method provided in this application.

[0086] This application also provides a chip, including: an input interface, an output interface, a processor, and a memory. The input interface, output interface, processor, and memory are connected through an internal connection path. The processor is used to execute code in the memory. When the code is executed, the processor is used to execute the method provided in the application embodiment.

[0087] It should be understood that the aforementioned processor can be a CPU (Central Processing Unit), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. General-purpose processors can be microprocessors or any conventional processor. It is worth noting that the processor can be a processor supporting Advanced Reduced Instruction Set Machines (ARM) architecture.

[0088] Further, optionally, the aforementioned memory may include read-only memory and random access memory. The memory may be volatile memory or non-volatile memory, or may include both. Non-volatile memory may include read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), or flash memory. Volatile memory may include random access memory (RAM), which serves as an external cache. By way of example, but not limitation, many forms of RAM are available. Examples include Static Random Access Memory (SRAM), Dynamic Random Access Memory (DRAM), Synchronous DRAM (SDRAM), Double Data Rate SDRAM (DDR SDRAM), Enhanced Synchronous DRAM (ESDRAM), Sync Link DRAM (SLDRAM), and Direct Rambus RAM (DR RAM).

[0089] In the above embodiments, implementation can be achieved, in whole or in part, through software, hardware, firmware, or any combination thereof. When implemented in software, it can be implemented, in whole or in part, as a computer program product. A computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the processes or functions according to this application are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transferred from one computer-readable storage medium to another.

[0090] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of those different embodiments or examples.

[0091] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "a plurality of" means two or more, unless otherwise explicitly specified.

[0092] Any process or method described in the flowchart or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or more executable instructions for implementing a particular logical function or process. Furthermore, the scope of the preferred embodiments of this application includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order depending on the functionality involved.

[0093] The logic and / or steps described in the flowchart or otherwise herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus or device (such as a computer-based system, a processor-included system or other system that can fetch and execute instructions from, an instruction execution system, apparatus or device).

[0094] It should be understood that various parts of this application can be implemented using hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented using software or firmware stored in memory and executed by a suitable instruction execution system. All or part of the steps of the methods in the above embodiments can be implemented by a program instructing related hardware, the program being stored in a computer-readable storage medium, which, when executed, includes one or a combination of the steps of the method embodiments.

[0095] Furthermore, the functional units in the various embodiments of this application can be integrated into a processing module, or each unit can exist physically separately, or two or more units can be integrated into a module. The integrated module can be implemented in hardware or as a software functional module. If the integrated module is implemented as a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium. This storage medium can be a read-only memory, a disk, or an optical disk, etc.

[0096] The above description is merely an exemplary embodiment of this application, but the scope of protection of this application is not limited thereto. Any person skilled in the art can easily conceive of various variations or substitutions within the technical scope described in this application, and these should all be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A fuel injector drive fault detection circuit, characterized in that, include: The high-side detection circuit is used to determine whether there is an overcurrent based on the high-side current sampling signal of the high-side drive circuit of the fuel injector, and outputs a high-side detection signal. The low-side detection circuit is used to determine whether there is an overcurrent based on the low-side current sampling signal of the low-side drive circuit of the injector, and outputs a low-side detection signal. A high-side pre-drive chip is used to pre-drive the high-side drive circuit. A low-side pre-drive chip is used to pre-drive the low-side drive circuit. Hardware logic circuitry is used to shut down the high-side pre-drive chip and the low-side pre-drive chip when either the high-side detection signal or the low-side detection signal indicates an overcurrent. The control unit is configured to receive the high-side current sampling signal, the low-side current sampling signal, the high-side detection signal, and the low-side detection signal, and determine the fault detection results of the high-side drive circuit and the low-side drive circuit based on whether the high-side current sampling signal or the low-side current sampling signal matches the current operating state of the injector, and whether the high-side detection signal or the low-side detection signal indicates overcurrent in each of the operating states.

2. The injector drive fault detection circuit according to claim 1, characterized in that, The high-side detection circuit includes a high-side hysteresis comparator circuit, which includes a high-side comparator. The inverting input of the high-side comparator is connected to the high-side current sampling signal. The high-side current sampling signal is the high-side sampling voltage output from the high-side sampling resistor connected in series in the high-side driving circuit. The non-inverting input of the high-side comparator is connected to a first voltage divider node, which is a voltage divider node between the output of the high-side comparator and the first reference voltage. The low-side detection circuit includes a low-side hysteresis comparator circuit, which includes a low-side comparator. The inverting input of the low-side comparator is connected to the low-side current sampling signal, which is the low-side sampling voltage output across the low-side sampling resistor connected in series in the low-side drive circuit. The non-inverting input of the low-side comparator is connected to a second voltage divider node, which is the voltage divider node between the output of the low-side comparator and the second reference voltage.

3. The injector drive fault detection circuit according to claim 1, characterized in that, The enable pin of the high-side pre-driver chip is active high and inactive low; the enable pin of the low-side pre-driver chip is active high and inactive low. The hardware logic circuit includes: The first diode has its anode connected to the enable terminal of the high-side pre-drive chip and its cathode connected to the high-side detection signal. The second diode has its anode connected to the enable terminal of the high-side pre-drive chip and its cathode connected to the low-side detection signal. The third diode has its anode connected to the enable terminal of the low-side pre-drive chip and its cathode connected to the high-side detection signal. The fourth diode has its anode connected to the enable terminal of the low-side pre-drive chip and its cathode connected to the low-side detection signal.

4. The injector drive fault detection circuit according to claim 1, characterized in that, The injectors are multiple; the low-side drive circuit includes multiple low-side drive sub-circuits that drive the multiple injectors in a one-to-one correspondence; the low-side pre-drive chip is multiple, and each low-side pre-drive chip is used to pre-drive each low-side drive sub-circuit in a one-to-one correspondence; the low-side current sampling signal is obtained by sampling the total current of the multiple low-side drive sub-circuits. The control unit is configured to, when the operating state is in the peak stage and the maintenance stage, if it is determined that the low-side detection signal indicates an overcurrent, control the high-side pre-drive chip to turn off, and poll and turn on each of the low-side pre-drive chips, and determine the fault detection result based on the low-side detection signal when each of the low-side drive sub-circuits is turned on.

5. The injector drive fault detection circuit according to claim 4, characterized in that, The control unit is also configured to, after polling and turning on each of the low-side pre-driver chips: If it is determined that the low-side detection signal indicates overcurrent when each of the low-side driving sub-circuits is turned on, then the fault detection result is determined to be a short circuit fault of the high-side driving circuit to the power supply. If it is determined that the low-side detection signal indicates no current flow when each of the low-side driving sub-circuits is turned on, then the fault detection result is determined to be a short circuit fault between the high-side driving circuit and the low-side driving circuit. If it is determined that the low-side detection signal indicates overcurrent when part of the low-side driver sub-circuit is turned on, then the fault detection result is determined to be a short circuit fault of the corresponding low-side driver sub-circuit to the power supply.

6. The injector drive fault detection circuit according to claim 4, characterized in that, The high-side drive circuit includes a high-voltage high-side drive sub-circuit for driving a high-voltage power supply to supply power to multiple injectors and a low-voltage high-side drive sub-circuit for driving a low-voltage power supply to supply power to multiple injectors; the high-side pre-drive chip includes a high-voltage high-side pre-drive chip for pre-drives the high-voltage high-side drive sub-circuit and a low-voltage high-side pre-drive chip for pre-drives the low-voltage high-side drive sub-circuit; the high-side current sampling signal is obtained by sampling the current of the branch where the low-voltage high-side drive sub-circuit is located; The control unit is configured to, when the operating state is the maintenance phase, determine the fault detection result as a short circuit to ground fault if it is determined that the high-side detection signal indicates an overcurrent, and when the operating state is the peak phase, determine the fault detection result as a short circuit to ground fault based on the fact that the change trend of the low-side current sampling signal over time does not conform to the preset current change trend of the peak phase.

7. The injector drive fault detection circuit according to any one of claims 1-6, characterized in that, The control unit is also used for: When the working state is that the injector is not driven after power-on, the fault detection result is determined to be a short circuit to ground fault based on the ratio of the high-side current sampling signal to the low-voltage power supply being less than a preset threshold. When the operating state is that the low-side drive circuit is turned on and the high-side drive circuit is turned off, the fault detection result is determined to be a power supply short circuit fault based on the ratio of the high-side current sampling signal to the low-voltage power supply being greater than the preset threshold.

8. A method for detecting injector drive faults, characterized in that, The method is applied to the injector drive fault detection circuit according to any one of claims 1-7, and the method includes: Receives high-side current sampling signal, low-side current sampling signal, high-side detection signal and low-side detection signal; Based on whether the high-side current sampling signal or the low-side current sampling signal matches the current operating state of the injector, and whether the high-side detection signal or the low-side detection signal indicates overcurrent, the fault detection results of the high-side drive circuit and the low-side drive circuit are determined.

9. The injector drive fault detection method according to claim 8, characterized in that, The determination of fault detection results for the high-side drive circuit and the low-side drive circuit includes: When the working state is that the injector is not driven after power-on, the fault detection result is determined to be a short circuit to ground fault based on the ratio of the high-side current sampling signal to the low-voltage power supply being less than a preset threshold. When the working state is that the low-side drive circuit is turned on and the high-side drive circuit is turned off, the fault detection result is determined to be a power supply short circuit fault based on the ratio of the high-side current sampling signal to the low-voltage power supply being greater than the preset threshold. When the operating state is in the maintenance phase, if it is determined that the high-side detection signal indicates an overcurrent, then the fault detection result is determined to be a short-circuit fault to ground. When the operating state is at its peak, if the trend of the low-side current sampling signal over time does not conform to the preset current trend of the peak stage, the fault detection result is determined to be a short-circuit fault to ground. When the operating state is in the peak phase and the maintenance phase, if it is determined that the low-side detection signal indicates an overcurrent, the high-side pre-driver chip is controlled to be turned off, and each of the low-side pre-driver chips is polled to be turned on: If it is determined that the low-side detection signal indicates overcurrent when each of the low-side driving sub-circuits is turned on, then the fault detection result is determined to be a short circuit fault of the high-side driving circuit to the power supply. If it is determined that the low-side detection signal indicates no current flow when each of the low-side driving sub-circuits is turned on, then the fault detection result is determined to be a short circuit fault between the high-side driving circuit and the low-side driving circuit. If it is determined that the low-side detection signal indicates overcurrent when part of the low-side driver sub-circuit is turned on, then the fault detection result is determined to be a short circuit fault of the corresponding low-side driver sub-circuit to the power supply.

10. An electronic device, characterized in that, It includes a memory, a processor, and a computer program stored in the memory, wherein the processor, when executing the computer program, implements the method of claim 8 or 9.

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