A controller for vehicle wheel speed detection and a vehicle

Abstract

This application provides a controller and a vehicle for wheel speed detection. The controller is used to connect to the vehicle's wheel speed sensor and includes a wheel speed detection circuit and a main control chip. The wheel speed detection circuit includes a first sub-circuit, a second sub-circuit, and a third sub-circuit. The first sub-circuit is used to connect or disconnect the wheel speed sensor and a first power supply. The second and first sub-circuits are used to detect open-circuit faults and / or short-circuit faults in the wheel speed detection circuit. The input terminal of the third sub-circuit is used to connect to the wheel speed sensor. The third sub-circuit includes two output terminals, which are used to connect to the main control chip and output level signals corresponding to the wheel speed signal from the wheel speed sensor. The wheel speed signal includes three current signals with different pulse levels. This controller is compatible with various types of wheel speed sensors, can accurately detect sensor faults, is highly practical, and reduces reliance on dedicated wheel speed processing chips.

Description

Technical Field

[0001] This application relates to the field of vehicles, and more particularly to a controller for vehicle wheel speed detection and an electric vehicle. Background Technology

[0002] In the field of vehicle wheel speed sensors, most wheel speed detection solutions use dedicated integrated chips or operational amplifier comparator circuits. The disadvantages of using dedicated integrated chips are that the sensor's internal parameters are already determined, making it impossible to adapt to all sensor specifications. Furthermore, the performance of chips from different manufacturers varies, and the diagnostic logic cannot meet the diagnostic needs of all sensors. In addition, wheel speed sensor chips developed by different manufacturers are not interchangeable, resulting in poor substitutability. In other words, current solutions relying on dedicated wheel speed detection chips cannot cover all sensor specifications, and the chips developed by different manufacturers are not interchangeable, leading to problems of poor substitutability and supply shortages. Summary of the Invention

[0003] This application provides a controller and a vehicle for vehicle wheel speed detection. The controller is compatible with various types of wheel speed sensors and can accurately detect sensor faults. It is highly practical and reduces the dependence on dedicated wheel speed processing chips.

[0004] In a first aspect, a controller for vehicle wheel speed detection is provided. This controller connects to a wheel speed sensor of the vehicle and includes a wheel speed detection circuit and a main control chip. The wheel speed detection circuit includes a first sub-circuit, a second sub-circuit, and a third sub-circuit. One end of the first sub-circuit is connected to one pole of the wheel speed sensor, and the other end is connected to a first power supply. The first sub-circuit is used to connect or disconnect the connection between the wheel speed sensor and the first power supply. The second sub-circuit is connected to the other pole of the wheel speed sensor. The second and first sub-circuits are used to detect open-circuit faults and / or short-circuit faults in the wheel speed detection circuit. The input terminal of the third sub-circuit is connected to the wheel speed sensor. The third sub-circuit includes two output terminals connected to the main control chip. These two output terminals output level signals corresponding to the wheel speed signal of the wheel speed sensor, including three current signals with different pulse levels.

[0005] In this application, the first sub-circuit can be regarded as a power supply circuit. When the first sub-circuit is turned on, the electrical energy output by the first power supply can be transmitted to the wheel speed sensor through the first sub-circuit, thereby powering the wheel speed sensor. The second sub-circuit can be regarded as a short circuit detection circuit, and the second sub-circuit can cooperate with the first sub-circuit to realize the open circuit detection and short circuit detection of the wheel speed detection circuit.

[0006] In this application, the third sub-circuit can be considered a wheel speed signal processing circuit, used to convert the wheel speed signal provided by the wheel speed sensor into a level signal and output it to the main control chip. The main control chip is responsible for parsing the level signal to determine the wheel speed and related data information (such as rotation direction, field amplitude, etc.). Furthermore, the third sub-circuit can process the current signals output by different types of wheel speed sensors. The main control chip can distinguish up to three pulse levels of current signals through the level signals output from its two output terminals, making the controller compatible with three different types of wheel speed sensors. These different types of wheel speed sensors include, but are not limited to, non-intelligent wheel speed sensors, PWM protocol intelligent wheel speed sensors, and AK protocol intelligent wheel speed sensors.

[0007] Based on the above scheme, and utilizing the first and second sub-circuits in the wheel speed detection circuit, the controller can achieve stable power supply to the wheel speed sensor and accurate open-circuit and / or short-circuit fault detection. Based on the third sub-circuit in the wheel speed detection circuit, the controller can be compatible with three different types of wheel speed sensors without adding additional adapter circuitry. This enhances the controller's practicality and reduces reliance on dedicated wheel speed processing chips.

[0008] In conjunction with the first aspect, in some implementations of the first aspect, the first sub-circuit includes a first signal input port, a first transistor, and a second transistor. The first signal input port is used to connect to a control pin of the main control chip. The base of the first transistor is connected to the first signal input port, the emitter of the first transistor is grounded, the collector of the first transistor is connected to the base of the second transistor, the emitter of the second transistor is connected to the other end of the first sub-circuit, and the collector of the second transistor is connected to one end of the first sub-circuit. The main control chip is used to control the on and off states of the first transistor, thereby controlling the on and off states of the second transistor.

[0009] In this application, the main control chip can control the conduction and cutoff of the first composite transistor via a first control signal, thereby controlling the conduction and cutoff of the second transistor. For example, the main control chip enables a control pin, causing the first transistor to conduct and the base potential of the second transistor to be pulled low. At this time, when the voltage difference between the base and emitter of the second transistor is greater than the transistor's conduction threshold, the second transistor connects the first power supply and the wheel speed sensor.

[0010] Based on the above scheme, the first sub-circuit can serve as a power supply circuit to provide a stable and reliable power supply to the wheel speed sensor, ensuring the stable operation of the wheel speed sensor.

[0011] In conjunction with the first aspect, in some implementations of the first aspect, the first sub-circuit further includes a first resistor and a third transistor. The first resistor is connected between the emitter of the second transistor and the other end of the first sub-circuit. The first resistor is also connected between the base and emitter of the third transistor, and the collector of the third transistor is grounded. Specifically, during the process of the wheel speed sensor receiving power from the first power source through the second transistor, when the current flowing through the first resistor exceeds a preset current, the third transistor conducts, causing the second transistor to turn off.

[0012] Optionally, the first transistor and the second transistor can be integrated into a composite transistor comprising two transistors, with each terminal of the two transistors connected to other electronic devices through the pins of the composite transistor.

[0013] Based on the above scheme, the controller can achieve hardware-level overcurrent protection through the first sub-circuit, resulting in higher reliability.

[0014] In conjunction with the first aspect, in some implementations of the first aspect, the second sub-circuit includes a second signal input port, a third composite transistor, and two signal output ports. The second signal input port is used to connect to another control pin of the main control chip, and one pin of the first composite transistor is used to connect to the second signal input port. One pole of the wheel speed sensor is used to connect to a sampling pin of the main control chip through one of the signal output ports. The main control chip is used to adjust the first control signal input through the first signal input port and detect the voltage of the sampling pin. Alternatively, the other pole of the wheel speed sensor is used to connect to another sampling pin of the main control chip through another of the signal output ports. The main control chip is also used to adjust the second control signal input through the second signal input port and detect the voltage of the other sampling pin.

[0015] In conjunction with the first aspect, in some implementations of the first aspect, the main control chip is used to control both the first control signal and the second control signal to be low-level signals. When the voltage value indicated by the voltage signal output from one sampling pin is greater than a first preset voltage, the main control chip confirms that one pole of the wheel speed sensor is short-circuited to the first power supply. When the voltage value indicated by the voltage signal output from the other sampling pin is greater than a second preset voltage, the main control chip confirms that the other pole of the wheel speed sensor is short-circuited to the first power supply.

[0016] In conjunction with the first aspect, in some implementations of the first aspect, when the first control signal is controlled to be a low-level signal and the second control signal is controlled to be a high-level signal, if the voltage indicated by the voltage signal output from the other sampling pin is less than a third preset voltage, the main control chip is also used to confirm that the other pole of the wheel speed sensor is short-circuited to ground. When the first control signal is controlled to be a high-level signal and the second control signal is controlled to be a low-level signal, if the voltage indicated by the voltage signal output from the other sampling pin is less than a fourth preset voltage, the main control chip confirms an open-circuit fault in the wheel speed sensor.

[0017] In conjunction with the first aspect, in some implementations of the first aspect, the first sub-circuit further includes a third signal output port, which is used to connect to another sampling pin of the main control chip. When the first control signal is controlled to be a high-level signal and the second control signal is controlled to be a low-level signal, when the voltage value indicated by the voltage signal output by the sampling pin is less than a fifth preset voltage, and the difference between the voltage value indicated by the voltage signal output by the sampling pin and the voltage value indicated by the voltage signal output by the other sampling pin is greater than a first difference threshold, the main control chip is also used to confirm that one pole of the wheel speed sensor is short-circuited to ground.

[0018] Based on the above scheme, the controller can quickly and accurately diagnose and locate open circuit faults, short circuit faults to ground, and power supply short circuit faults of wheel speed sensors without relying on dedicated wheel speed chips, thus achieving high reliability and strong practicality.

[0019] In conjunction with the first aspect, in some implementations of the first aspect, during the process of the first sub-circuit powering the wheel speed sensor, when the difference between the voltage signal output by one sampling pin and the voltage signal indicated by the voltage signal output by another sampling pin is greater than a second difference threshold, or the voltage indicated by the voltage signal output by another sampling pin is greater than a sixth preset voltage, the main control chip is also used to control the first transistor and the second transistor to disconnect.

[0020] Based on the above scheme, the controller can detect the operating status of the wheel speed sensor in real time and disconnect the power supply to the wheel speed sensor in time when there is an overcurrent risk, thereby realizing active current limiting protection for the wheel speed sensor at the software level.

[0021] In conjunction with the first aspect, in some implementations of the first aspect, the third sub-circuit includes two comparators. The non-inverting inputs of the two comparators are connected to the inputs of the third sub-circuit, and the outputs of the two comparators are respectively connected to the two outputs of the third sub-circuit. The inverting input of one of the two comparators is connected to a first reference voltage, and the inverting input of the other comparator is connected to a second reference voltage. The first reference voltage corresponds to a current signal of a first pulse level, and the second reference voltage corresponds to a current signal of a second pulse level. The three pulse levels, from high to low, are the first pulse level, the second pulse level, and the third pulse level.

[0022] The current of the first pulse level is 28mA, the current of the second pulse level is 14mA, and the current of the third pulse level is 7mA.

[0023] Based on the above scheme, the controller can be compatible with various types of wheel speed sensors through a third sub-circuit including two comparators, thus expanding its application range.

[0024] In a second aspect, an electric vehicle is provided, the electric vehicle including wheels, wheel speed sensors and a controller as described in the first aspect or any implementation thereof, the controller being used to connect to the wheel speed sensors, the wheel speed sensors being used to detect the wheel speed of the wheels.

[0025] The supplementary solutions and technical effects provided in the second and third aspects above can be found in the corresponding descriptions in the first aspect, and will not be repeated here. Attached Figure Description

[0026] Figure 1 A schematic diagram of an electric vehicle 01 provided in an embodiment of this application; Figure 2 This is a schematic diagram of the structure of a controller 50 provided in an embodiment of this application; Figure 3 A circuit diagram of a controller 50 provided for an embodiment of this application; Figure 4 A schematic diagram of an initialization diagnostic process for a controller 50 provided in an embodiment of this application; Figure 5 This is a schematic diagram illustrating the specific process of overcurrent / overheat detection by a controller 50 provided in an embodiment of this application. Detailed Implementation

[0027] The technical solutions in this application will now be described with reference to the accompanying drawings.

[0028] References to “some embodiments” and the like in this specification mean that one or more embodiments of this application include a particular feature, structure, or characteristic described in connection with that embodiment. Therefore, phrases such as “some embodiments” appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean “one or more, but not all, embodiments”, unless otherwise specifically emphasized. The terms “comprising,” “including,” “having,” and variations thereof mean “including, but not limited to,” unless otherwise specifically emphasized.

[0029] Wheel speed is one of the primary input signals for acquiring vehicle status during operation. In chassis control systems such as Anti-lock Braking System (ABS), Traction Control System (TCS), and Hill-start Assist Control (HAC), vehicles typically need to perform corresponding operations based on wheel speed information or vehicle speed calculated from wheel speed information. In drive system-related fields such as transmission control, torque command generation, and four-wheel drive control, rapid and accurate calculation and judgment based on wheel speed information are also required. Furthermore, with the development and popularization of intelligent driving, slow or inaccurate wheel speed signal updates will significantly impact the control effectiveness of the vehicle's real-time control system. In other words, vehicle control systems have higher requirements for the real-time performance, reliability, and robustness of wheel speed and other signals.

[0030] In the field of vehicle wheel speed sensors, most wheel speed detection solutions utilize dedicated integrated chips. However, because the internal parameters of the sensors are already determined, the chips cannot cover all sensor specifications, and the performance of chips from different manufacturers varies, resulting in diagnostic logic that cannot meet the diagnostic needs of all sensors. Furthermore, wheel speed sensor chips developed by different manufacturers are not interchangeable, leading to poor substitutability. In other words, current solutions relying on dedicated wheel speed detection chips cannot cover all sensor specifications, and the chips developed by different manufacturers are not universally compatible, resulting in poor substitutability and supply shortages.

[0031] In view of this, embodiments of this application provide a controller and a vehicle for vehicle wheel speed detection. The controller is compatible with various types of wheel speed sensors and can accurately detect sensor faults. It can reduce the dependence on dedicated wheel speed processing chips and is highly practical.

[0032] Figure 1 This is a schematic diagram of an electric vehicle 01 provided in an embodiment of this application. Figure 1As shown, the electric vehicle 01 includes a drive system 10, a braking system 20, and a power battery 30. The powertrain 10 receives electrical energy from the power battery 30 and provides kinetic energy to the electric vehicle 01. The drive system 10, also referred to as the powertrain, drives the electric vehicle 01. The drive system 10 includes a motor controller and a drive motor. The motor controller outputs current to the drive motor to control the output torque of the drive motor to drive the wheels. The braking system 20 provides braking force to the electric vehicle 01 when it is in a braking state.

[0033] It is understood that the vehicle 01 in this application embodiment can be any type of vehicle such as a sedan, truck, or passenger bus, or it can be a tricycle, two-wheeled vehicle, train, or other transportation device for carrying passengers or goods, or other types of vehicles powered by a power battery. This application embodiment does not limit this. The vehicle includes, but is not limited to, pure electric vehicles (pure EV / battery EV), hybrid electric vehicles (HEV), range-extended electric vehicles (REEV), and plug-in hybrid electric vehicles (plug-in hybrid electric vehicles). In hybrid electric vehicles (PHEVs), new energy vehicles (NEVs), etc.

[0034] It is understood that the specific type of powertrain 10 is not limited in the embodiments of this application. As an example and not a limitation, the powertrain described above can be a centralized powertrain, a hub motor powertrain, or a wheel-side motor powertrain. In the hub motor powertrain, the motor and reducer are directly mounted in the wheel rim, eliminating transmission components such as half-shafts, universal joints, differentials, and gearboxes; in the wheel-side motor powertrain, the motor is mounted on the subframe.

[0035] In this embodiment, the electric vehicle 01 has a single-motor drive architecture, a dual-motor drive architecture, a tri-motor drive architecture, or a quad-motor drive architecture. The electric vehicle 01 can be a distributed quad-motor drive architecture, with the drive motors positioned beside the driving wheels and controlled by individual motor controllers. Alternatively, the electric vehicle 01 can be a centralized drive motor architecture, with drive motors for driving the two front wheels or two rear wheels grouped together. There can be one or more motor controllers. A one-to-one correspondence can exist between the motor controller and the drive motors, or one motor controller can correspond to multiple drive motors. The motor controller is used to control the output torque of one or more drive motors to drive the electric vehicle 01.

[0036] It is understood that the brake in the braking system of this application embodiment may be an electronic hydraulic brake (EHB), an electronic mechanical brake (EMB), or other types of brakes, without limitation.

[0037] In one example, the braking system 20 includes a central controller 21 and four independent wheel-end braking devices 22. Each wheel-end braking device 22 mainly consists of a brake controller, a brake pedal, and a brake (not shown in the figure). The central controller 21 can generate a braking signal based on the travel of the brake pedal and output the braking signal to the brake controller of one or more wheel-end braking devices 22. The brake can then output braking force to the corresponding wheel according to the indication of the braking signal, thereby preventing the wheel from rotating or preventing the wheel from rotating. It can be understood that during the braking process of vehicle 01, the greater the travel of the brake pedal, the greater the braking force indicated by the brake signal, the greater the braking force output by the brake, and the faster the vehicle 01's speed decreases.

[0038] In one embodiment, the vehicle 01 further includes a vehicle controller 40. When the vehicle 01 is in a driving state, the vehicle controller 40 calculates the vehicle torque demand based on the accelerator pedal opening during driving and sends a torque signal to each of the four motor controllers. Each motor controller controls the corresponding motor to output torque to drive the corresponding wheel according to the torque signal. When the vehicle 01 is in a braking state, the vehicle controller 40 receives a braking signal and sends an energy recovery command to the four motor controllers. In response to the energy recovery command, the motor controllers control the drive motor to operate in a power generation state. The drive motor converts the kinetic energy of the vehicle's wheels into electrical energy and outputs counter-torque to the wheels of the vehicle 01 to provide braking force to the vehicle 01.

[0039] When vehicle 01 is in a braking state, braking system 20 provides braking force to the wheels to reduce the vehicle speed under the action of braking force. Optionally, vehicle controller 40 receives braking signals and sends energy recovery commands to motor controller. In response to the energy recovery commands, motor controller controls the drive motor to operate in a power generation state. The drive motor converts the kinetic energy of the vehicle wheels into electrical energy and outputs counter-torque to the wheels of vehicle 01 to provide braking force to vehicle 01.

[0040] Furthermore, the drive system 10, braking system 20, and vehicle controller 40 are connected via a Controller Area Network (CAN) bus, and the specific communication connection method is not limited in this embodiment. For example, the motor controller in the drive system 10 and the vehicle controller 40 can communicate via a private CAN network, the central controller of the braking system 20 and the vehicle controller 40 can communicate via a public CAN network, and the central controller and each wheel-end braking device can communicate via another private CAN network. Alternatively, the vehicle controller 40 can communicate with the motor controller in the drive system 10 and the central controller in the braking system 20 via the same CAN network.

[0041] The architecture of the embodiments of this application has been described above. The following, in conjunction with specific embodiments, provides a detailed description of the control method provided by this application, its specific implementation, and the vehicle controller implementing the control method. For ease of understanding, please refer to [link to relevant documentation]. Figure 2 , Figure 2 This is a schematic diagram of a controller provided in an embodiment of this application.

[0042] It is understood that the controller provided in this application can be the vehicle controller 40, any motor controller 12 in the powertrain 10, or other separately configured controllers with control capabilities, without limitation.

[0043] like Figure 2 As shown, in some embodiments, the controller 50 includes a wheel speed detection circuit 51 and a main control chip 52. The wheel speed detection circuit includes a first sub-circuit, a second sub-circuit, and a third sub-circuit.

[0044] In this embodiment, one end of the first sub-circuit is used to connect to one pole of the wheel speed sensor 53, and the other end of the first sub-circuit is used to connect to the first power supply. The first sub-circuit is used to connect or disconnect the connection between the wheel speed sensor 53 and the first power supply. In this embodiment, the first sub-circuit can be regarded as a power supply circuit. When the first sub-circuit is turned on, the electrical energy output by the first power supply can be transmitted to the wheel speed sensor through the first sub-circuit, thereby powering the wheel speed sensor.

[0045] The second sub-circuit is used to connect to the other pole of the wheel speed sensor. The second and first sub-circuits are used to detect open-circuit and / or short-circuit faults in the wheel speed detection circuit. In this embodiment, the second sub-circuit can be considered a short-circuit detection circuit, and it can cooperate with the first sub-circuit to achieve open-circuit and short-circuit detection of the wheel speed detection circuit (hereinafter referred to as fault detection for brevity). In actual implementation, the timing for the first and second sub-circuits to perform fault detection on the wheel speed detection circuit includes, but is not limited to, at least one of the following: after the wheel speed sensor is powered on, before it starts running, during the operation of the wheel speed sensor, or after the wheel speed sensor stops running and before it is powered off.

[0046] It is understood that the embodiments of this application do not limit the specific connection method between the first sub-circuit and the second sub-circuit and the wheel speed sensor. In one example, one end of the first sub-circuit is connected to the positive terminal of the wheel speed sensor, and the second sub-circuit is connected to the negative terminal of the wheel speed sensor. In another example, one end of the first sub-circuit is connected to the negative terminal of the wheel speed sensor, and the second sub-circuit is connected to the positive terminal of the wheel speed sensor.

[0047] The third sub-circuit has an input terminal for connecting to a wheel speed sensor. It includes two output terminals for connecting to the main control chip. These output terminals output high-level and low-level signals corresponding to the wheel speed signal from the wheel speed sensor, respectively. The wheel speed signal includes at least three current signals with different pulse levels. In this embodiment, the third sub-circuit can be considered a wheel speed signal processing circuit, used to convert the wheel speed signal provided by the wheel speed sensor into a level signal and output it to the main control chip. The main control chip is responsible for parsing the level signal to determine the wheel speed and related data information (such as rotation direction, field amplitude, etc.).

[0048] It is understandable that current mainstream wheel speed sensors include three types: non-intelligent wheel speed sensors, PWM protocol intelligent wheel speed sensors, and AK protocol intelligent wheel speed sensors. The non-intelligent wheel speed sensors and PWM protocol intelligent wheel speed sensors output current waveforms with two pulse levels. The typical high current output of these two types of wheel speed sensors is 14 mA, and the typical low current is 7 mA. The AK protocol intelligent wheel speed sensors output current waveforms with three different pulse levels: a typical 28 mA speed pulse high current, a typical 14 mA current for additional information data bits, and a typical 7 mA low current.

[0049] In this embodiment, the third sub-circuit can process the current signals output by the three types of wheel speed sensors mentioned above, and output level signals through two output terminals respectively. The main control chip can then distinguish up to three pulse levels of current signals through the level signals, making the controller compatible with the three types of wheel speed sensors and thus having a wider range of applications. The specific processing method of the current signal by the third sub-circuit will be described in detail later and will not be repeated here.

[0050] According to embodiments of this application, based on the first and second sub-circuits in the wheel speed detection circuit, the controller can achieve stable power supply to the wheel speed sensor and accurate open-circuit and / or short-circuit fault detection. Furthermore, based on the third sub-circuit in the wheel speed detection circuit, the controller can be compatible with three different types of wheel speed sensors without adding additional adapter circuitry. Based on the above structure, the controller is highly practical and reduces reliance on dedicated wheel speed processing chips.

[0051] Figure 3 This is a schematic diagram of a wheel speed detection circuit provided in an embodiment of this application. The following is in conjunction with... Figure 3 The specific circuit of the wheel speed sensor and the specific way in which it achieves its function are explained.

[0052] In some embodiments, the first sub-circuit includes a first signal input port, a first transistor, and a second transistor. The first signal input port is used to connect to a control pin of the main control chip. The base of the first transistor is connected to the first signal input port, the emitter of the first transistor is grounded, the collector of the first transistor is connected to the base of the second transistor, the emitter of the second transistor is also connected to the other end of the first sub-circuit, and the collector of the second transistor is connected to one end of the first sub-circuit. The main control chip controls the on / off state of the first transistor to control the on / off state of the second transistor.

[0053] like Figure 3 As shown, the first sub-circuit includes diode D1, first composite transistor Q1, second transistor Q2, resistors R32, R20, R15, R11, and R16. The anode of diode D1 is connected to the first power supply, the cathode of diode D1 is connected to the base of transistor Q2 through resistors R11 and R15, and the cathode of diode D1 is connected to the emitter of transistor Q2 through resistor R16.

[0054] The first composite transistor Q1 consists of two transistors. The emitter, base, and collector of the upper transistor (i.e., the first transistor) are connected to pins 1, 2, and 6 of the composite transistor, respectively. Specifically, pin 1 of the first composite transistor Q1 is grounded. Pin 2 is connected to its own pin 1 via resistor R20. Pin 2 is also connected to a control pin WSS_12V_EN of the main control chip via resistor R32 to receive the first control signal. Pin 6 is connected to the base of the second transistor Q2 via resistor R15.

[0055] The collector, emitter, and base of the lower transistor (i.e., the third transistor) of the first composite transistor Q1 are connected to pins 3, 4, and 5 of the first composite transistor Q1, respectively. Specifically, pin 3 of the first composite transistor Q1 is grounded through capacitor C5, pin 4 is connected to the cathode of diode D1, and pin 5 is connected to the emitter of the second transistor Q2 through resistor R12. The collector of the second transistor Q2 is connected to the positive interface WSS+ of the wheel speed sensor.

[0056] In this embodiment, the main control chip can control the conduction and cutoff of the upper transistor in the first composite transistor Q1 via a first control signal, thereby controlling the conduction and cutoff of the second transistor Q2. For example, the main control chip enables the control pin WSS_12V_EN (i.e., inputs a high-level first control signal), which connects to pin 2 of the first composite transistor Q1. This pulls up the potential of the base of a transistor. When the voltage difference between the base and emitter of this transistor exceeds the transistor's conduction threshold, pins 1 and 6 of the first composite transistor Q1 conduct, causing the potential of the base of the second transistor Q2 to drop. At this time, when the voltage difference between the base and emitter of the second transistor Q2 exceeds the transistor's conduction threshold, the second transistor Q2 connects the first power supply and the wheel speed sensor. For example, if the main control chip disables the control pin WSS_12V_EN (i.e., the first control signal with a low input level), the voltage difference between the base and emitter of the aforementioned transistor is less than the transistor's turn-on threshold. The connection between pins 1 and 6 of the first composite transistor Q1 is broken, and the base of the second transistor Q2 is connected to the cathode of diode D1 through resistors R11 and R15. At this time, the voltage difference between the base and emitter of the second transistor Q2 is less than the transistor's turn-on threshold, and the second transistor Q2 disconnects the connection between the first power supply and the wheel speed sensor.

[0057] According to the embodiments of this application, the first sub-circuit can serve as a power supply circuit to provide a stable and reliable power supply to the wheel speed sensor, ensuring the stable operation of the wheel speed sensor.

[0058] In some embodiments, the first sub-circuit further includes a first resistor and a third transistor. The first resistor is connected between the emitter of the second transistor and the other end of the first sub-circuit. The first resistor is also connected between the base and emitter of the third transistor, and the collector of the third transistor is grounded. Specifically, during the process where the wheel speed sensor receives power from the first power source through the second transistor, when the current flowing through the first resistor exceeds a preset current, the third transistor conducts, causing the second transistor to turn off.

[0059] Continue to refer to Figure 3 The first resistance is Figure 3 The emitter of the second transistor Q2 is connected to the anode of the diode D1 through resistor R16, and pin 5 of the first composite transistor Q1 is connected to the anode of the diode D1 through resistors R16 and R12.

[0060] In this embodiment, during the operation of the wheel speed sensor, or in other words, during the process of the second transistor Q2 being turned on to supply power to the wheel speed sensor from the first power supply, the current output by the first power supply generates a voltage drop through resistor R16. Based on the aforementioned connection relationship, this voltage drop is equal to the voltage difference between the base and emitter of the third transistor in the first composite transistor Q1. When the current exceeds a preset current, the voltage drop generated by this current exceeds the transistor's turn-on threshold, causing the third transistor to turn on. This turns on pins 3 and 4 of the first composite transistor Q1, pulling the potential of the emitter of the second transistor Q2 low. At this time, the voltage difference between the base and emitter of the second transistor Q2 is less than the transistor's turn-on threshold, causing the second transistor Q2 to turn off, thus shutting off the circuit containing the wheel speed sensor due to overcurrent.

[0061] According to the embodiments of this application, the first sub-circuit also implements overcurrent protection function in hardware, making the controller more reliable.

[0062] In some embodiments, the second sub-circuit includes a second signal input port, a composite transistor, and two signal output ports. The second signal input port is used to connect to another control pin of the main control chip, and one pin of the composite transistor is used to connect to the second signal input port. One pole of the wheel speed sensor is used to connect to a sampling pin of the main control chip through one signal output port. The main control chip is used to adjust a first control signal input through the first signal input port to detect the voltage at one pole of the wheel speed sensor. Alternatively, the other pole of the wheel speed sensor is used to connect to another sampling pin of the main control chip through another signal output port. The main control chip is also used to adjust a second control signal input through the second signal input port to detect the voltage at the other pole of the wheel speed sensor.

[0063] like Figure 3As shown, the second sub-circuit includes a third composite transistor Q3 (i.e., the aforementioned composite transistor), resistors R19, R20, R21, R22, and R23. The third composite transistor Q3 is composed of two transistors. The emitter, base, and collector of the lower transistor of Q3 are connected to pins 1, 2, and 6 of the composite transistor, respectively. Pin 1 of Q3 is grounded, and pin 2 is grounded and connected to its own pin 1 via resistor R20. Pin 2 is also connected to another control pin, WSS_STG_EN, of the main control chip via resistor R19 to receive the second control signal. Pin 6 of Q3 is connected to its own pins 4 and 5. Pin 6 is connected to its own pin 5 via resistor R21, and pin 6 is also connected to its own pin 4 via resistors R21 and R22.

[0064] The collector, emitter, and base of the upper-side transistor Q3 are connected to pins 3, 4, and 5 of Q3, respectively. Specifically, pin 3 of Q3 is connected to the negative interface WSS- of the wheel speed sensor via resistor R23, and a 5V power supply is drawn between pin 4 and resistor R22. The positive interface WSS+ of the wheel speed sensor is connected to a sampling pin WSS_12V_ADC2 of the main control chip via resistor R13, and the negative interface WSS- of the wheel speed sensor is connected to another sampling pin WSS_ADC of the main control chip via resistor R35.

[0065] In this embodiment, the main control chip can detect the voltage of the positive interface WSS+ of the wheel speed sensor by adjusting the level of the first control signal and receiving the signal through the sampling pin WSS_12V_ADC2. Furthermore, the main control chip can detect the voltage of the negative interface WSS- of the wheel speed sensor by adjusting the level of the second control signal and receiving the signal through the sampling pin WSS_ADC. Further, based on the voltages of the positive and negative interfaces of the wheel speed sensor, the main control chip can perform open-circuit and short-circuit detection on the wheel speed detection circuit.

[0066] In some embodiments, the third sub-circuit includes two comparators. The non-inverting inputs of the two comparators are connected to the input of the third sub-circuit, and the outputs of the two comparators are respectively connected to the two outputs of the third sub-circuit. The inverting input of one of the comparators is connected to a first reference voltage, and the inverting input of the other comparator is connected to a second reference voltage. The first reference voltage corresponds to a current signal of a first pulse level, and the second reference voltage corresponds to a current signal of a second pulse level. The three pulse levels, from high to low, are the first pulse level, the second pulse level, and the third pulse level.

[0067] In this embodiment, the third sub-circuit can be divided into a wheel speed signal conversion circuit and a wheel speed signal processing circuit. The wheel speed signal conversion circuit is connected between the negative terminal WSS- of the wheel speed sensor and the wheel speed signal processing circuit. As shown in the figure, the wheel speed signal conversion circuit includes resistors R1 and R2, and a pull-down circuit consisting of multiple parallel sampling resistors R3, R4, R5, R6, and R7 connected between them. It is easy to understand that the current signal from the wheel speed sensor can be converted into a voltage signal by the wheel speed signal conversion circuit, and then input into the wheel speed signal processing circuit for comparison with different reference voltages by a comparator.

[0068] The current of the first pulse level is 28mA, the current of the second pulse level is 14mA, and the current of the third pulse level is 7mA.

[0069] Continue to refer to Figure 3 The wheel speed signal processing module includes comparator U1, comparator U2, resistors R30, R27, R26, R28, R25, R24, R33, R8, R9, R10, capacitors C3, C4, C8, C7, C10, C11, a first reference power supply, a second reference power supply, a third power supply, a fourth power supply, and a fifth power supply.

[0070] In this configuration, the first output terminal of comparator U1 serves as a signal output terminal WSO_PWM1 for the wheel speed signal processing module. The second negative terminal of comparator U1 is grounded. The third positive input terminal of comparator U1 is grounded via resistor R27 and capacitor C8. A 5V reference power supply is drawn between resistor R27 and capacitor C8. The third positive input terminal of comparator U1 is also grounded via resistor R26. The fourth negative input terminal of comparator U1 is connected to the negative interface WSS- of the wheel speed sensor via resistors R1 and R2. The fifth positive terminal of comparator U1 is connected to both a 5V power supply and grounded via capacitor C10. Based on this connection method, the reference voltage of comparator U1 is the voltage divider of the 5V reference source by resistors R26 and R27. In practical implementation, the first reference voltage can be flexibly adjusted by changing the resistance values ​​of resistors R26 and / or R27, for example, the first reference voltage of comparator U1 can be matched with a typical current signal of 14mA.

[0071] In this configuration, output terminal 1 of comparator U2 serves as another signal output terminal, WSO_PWM2, for the wheel speed signal processing module. The negative terminal 2 of comparator U2 is grounded. The positive input terminal 3 of comparator U2 is grounded via resistor R25 and capacitor C7. A 5V reference power supply is drawn between resistor R25 and capacitor C7. The positive input terminal 3 of comparator U2 is also grounded via resistor R24. The negative input terminal 4 of comparator U2 is connected to the negative terminal WSS- of the wheel speed sensor via resistors R1 and R2. The positive terminal 5 of comparator U2 is connected to both a 5V power supply and grounded via capacitor C11. Based on this connection method, the reference voltage of comparator U2 is a voltage divider formed by resistors R24 and R25. In practical implementation, the second reference voltage can be flexibly adjusted by changing the resistance values ​​of resistors R24 and / or R25, for example, by corresponding the second reference voltage of comparator U2 to a typical 28mA current signal.

[0072] Optionally, output terminal 1 of comparator U1 is also connected to a 5V power supply via resistor R9 and grounded via capacitor C3. Similarly, output terminal 1 of comparator U2 is also connected to a 5V power supply via resistor R10 and grounded via capacitor C4.

[0073] It's easy to understand that when the wheel speed sensor current is lower than the current corresponding to the first reference voltage (V / R sampling), both comparators U1 and U2 output low-level signals. When the wheel speed sensor current is between the current corresponding to the first and second reference voltages, comparator U1 outputs a high-level signal, and comparator U2 outputs a low-level signal. When the wheel speed sensor current is higher than the current corresponding to the second reference voltage, both comparators U1 and U2 output high-level signals. The current corresponding to the first reference voltage is between the current values ​​of the second and third pulse levels, for example, 10mA. Similarly, the current corresponding to the second reference voltage is between the current values ​​of the first and second pulse levels, for example, 20mA. Thus, when the wheel speed sensor is a non-intelligent or intelligent PWM type sensor, the main control chip can directly analyze the wheel speed through the level signal output by comparator U1 via WSO_PWM1. When the wheel speed sensor is an AK protocol wheel speed sensor, the main control chip can combine comparator U1 and comparator U2 to analyze the wheel speed through the level signals output by WSO_PWM1 and WSO_PWM2.

[0074] According to the embodiments of this application, the controller is compatible with various types of wheel speed sensors, thus having a wider range of applications.

[0075] In some embodiments, the main control chip is specifically used to control both the first control signal and the second control signal to be low-level signals. When the voltage value indicated by the voltage signal output from one sampling pin is less than a first preset voltage, the main control chip confirms that one pole of the wheel speed sensor is short-circuited to the first power supply. When the voltage value indicated by the voltage signal output from the other sampling pin is less than a second preset voltage, the main control chip confirms that the other pole of the wheel speed sensor is short-circuited to the first power supply.

[0076] In this embodiment, the main control chip controls the first control signal to a low level, turning off the upper transistor of the first composite transistor Q1 and the second transistor Q2. At this time, the main control chip reads a voltage value of V1 through the sampling pin WSS_12V_ADC2. If V1 is greater than the first preset voltage, it indicates that the positive interface WSS+ of the wheel speed sensor is short-circuited to the power supply. The main control chip controls the second control signal to a low level, turning off the third composite transistor Q3. At this time, the main control chip reads a voltage value of V2 through the sampling pin WSS_ADC. If V2 is greater than the second preset voltage, it indicates that the negative interface WSS- of the wheel speed sensor is short-circuited to the power supply. The first preset voltage can be exemplarily 6V, and the second preset voltage can be exemplarily 4.5V.

[0077] According to the embodiments of this application, the controller can quickly locate the short circuit fault of the wheel speed sensor to the power supply without the need for a dedicated chip, and has high reliability and strong practicality.

[0078] In some embodiments, the main control chip controls the first control signal to be a low-level signal and the second control signal to be a high-level signal. When the voltage value indicated by the voltage signal output from another sampling pin is less than a third preset voltage, the main control chip confirms that the other pole of the wheel speed sensor is short-circuited to ground.

[0079] In this embodiment, the main control chip controls the first control signal to a low level and adjusts the second control signal to a high level, turning on the third composite transistor Q3. At this time, the main control chip reads the voltage value V3 through the sampling pin WSS_ADC. If V3 is less than the third preset voltage, it indicates that the negative terminal interface WSS- of the wheel speed sensor is short-circuited to ground.

[0080] According to the embodiments of this application, the controller can quickly locate the wheel speed sensor's ground short circuit fault, without the need for a dedicated chip, and has high reliability and strong practicality.

[0081] In some embodiments, the first sub-circuit further includes a third signal output port, which is used to connect to another sampling pin of the main control chip. The main control chip is also used to control the first control signal to be a high-level signal and the second control signal to be a low-level signal. When the voltage value indicated by the voltage signal output by a sampling pin WSS_12V_ADC2 is less than a fifth preset voltage, and the difference between the voltage value indicated by the voltage signal output by a sampling pin WSS_12V_ADC2 and the voltage value indicated by the voltage signal output by another sampling pin WSS_12V_ADC1 is greater than a first difference threshold, the main control chip confirms that one pole of the wheel speed sensor is short-circuited to ground.

[0082] In this embodiment, the aforementioned sampling pin is WSS_12V_ADC1 in the figure. The anode of diode D1 is connected to sampling pin WSS_12V_ADC1 through resistor R18. When the main control chip controls the first control signal to be high and the second control signal to be low, the first composite transistor Q1 is turned on and the third composite transistor Q3 is turned off. At this time, the voltage value read by the main control chip through sampling pin WSS_12V_ADC2 is V5, and the voltage value read by the main control chip through sampling pin WSS_12V_ADC1 is V6. If V5 is less than the fifth preset voltage, and the absolute value of the difference between V6 and V5 is less than the first preset difference, the main control chip confirms that the positive interface WSS+ of the wheel speed sensor is short-circuited to ground. Here, the fifth preset voltage is exemplarily 1V, and the first difference threshold is exemplarily the product of I2 and the resistance value of R16, where I2 is the current value of the positive interface WSS+ of the wheel speed sensor short-circuited to ground under the minimum supply voltage.

[0083] According to the embodiments of this application, the controller can quickly locate the wheel speed sensor's ground short circuit fault, without the need for a dedicated chip, and has high reliability and strong practicality.

[0084] In some embodiments, when the main control chip controls the first control signal to be a high-level signal and the second control signal to be a low-level signal, if the voltage indicated by the voltage signal output by another sampling pin is less than the fourth preset voltage, the main control chip confirms an open-circuit fault in the wheel speed sensor.

[0085] In this embodiment, the main control chip controls the first control signal to a high level and the second control signal to a low level. At this time, the voltage value read by the main control chip through the sampling pin WSS_ADC is V4. If V4 is less than a fourth preset voltage, provided the main control chip confirms that the wheel speed sensor is not short-circuited to ground, the main control chip confirms an open-circuit fault in the wheel speed sensor. The fourth preset voltage is exemplarily 0.5V.

[0086] According to the embodiments of this application, the controller can quickly diagnose open-circuit faults in wheel speed sensors without the need for dedicated chips, and is highly reliable and practical.

[0087] In some embodiments, when the main control chip controls the first control signal to be a high-level signal and controls the second control signal to be a low-level signal, if the difference between the voltage value indicated by the voltage signal output by one sampling pin WSS_12V_ADC2 and the voltage value indicated by the voltage signal output by another sampling pin WSS_12V_ADC1 is greater than a third difference threshold, or if the voltage value indicated by the voltage signal output by another sampling pin WSS_ADC is greater than a seventh preset voltage, the main control chip confirms that the wheel speed sensor has an overcurrent fault.

[0088] In this embodiment, when the main control chip controls the first control signal to be high and the second control signal to be low, if the difference between V5 and V6 read by the main control chip through WSS_12V_ADC2 and WSS_12V_ADC1 is greater than the third difference threshold, the main control chip confirms that the wheel speed sensor has an overcurrent fault. Alternatively, if the main control chip reads V4 through WSS_ADC which is greater than the seventh preset voltage, the main control chip confirms that the wheel speed sensor has an overcurrent fault. The second difference threshold is exemplarily the product of I1 and the resistance of R16, the seventh preset voltage can be exemplarily the product of I1 and the resistance of the sampling resistor, I1 is the preset overcurrent threshold, and the sampling resistor can be exemplarily any one of R3, R4, R5, R6, and R7 in the figure.

[0089] According to the embodiments of this application, the controller can realize overcurrent detection of the wheel speed sensor without the need for a dedicated chip, and has high reliability and strong practicality.

[0090] In some embodiments, the main control chip controls the second control signal to be high and controls the frequency of the second control signal to a preset frequency. When the frequency of the level signal output from any output port of the third sub-circuit is different from the preset frequency, the main control chip confirms a fault in the third sub-circuit.

[0091] In this embodiment, the main control chip controls the second control signal to be high, at which time the third composite transistor Q3 is turned on. When the third sub-circuit is active, the frequencies of the level signals output from the two output ports will not change from the frequency of the second control signal. Therefore, when the main control chip reads that the frequency of the level signal output from any output port of the third sub-circuit is different from the frequency of the second control signal, the main control chip can confirm a fault in the third sub-circuit. The preset frequency can be exemplarily 1 kHz.

[0092] According to the embodiments of this application, the controller can perform self-testing of its own wheel speed signal processing circuit without the need for a dedicated chip, thus achieving high reliability and strong practicality.

[0093] Figure 4 An initialization diagnostic process for a controller 50 provided in an embodiment of this application is shown.

[0094] As shown in the figure, the main control chip first controls both the first and second control signals to a low level, causing both the first composite transistor Q1 and the third composite transistor Q3 to disconnect. Then, based on the voltage values ​​V1 read by WSS_12V_ADC2 and V2 read by WSS_ADC, it determines whether there is a short circuit to the power supply at the positive terminal WSS+ and negative terminal WSS- of the wheel speed sensor. If the determination result is that the fault exists, the main control chip sends a fault signal to the connected controller to prompt the driver to handle the fault promptly. This fault signal can indicate only a fault in the wheel speed sensor, or it can indicate the specific fault point through a preset fault code, thereby assisting the driver and maintenance personnel in quickly locating and repairing the fault. If the determination result is that the fault does not exist, the main control chip continues to perform a self-test.

[0095] Subsequently, the main control chip maintains the first control signal at a low level and adjusts the second control signal to a high level, causing the third composite transistor Q3 to switch to the conducting state. This allows it to determine whether there is a short circuit to ground at the negative terminal of the wheel speed sensor, WSS-, based on the voltage value V3 read from WSS_ADC. If the determination is yes, the main control chip sends a fault signal to other connected controllers or other units within those controllers. If the determination result indicates that the fault does not exist, the main control chip continues its self-test.

[0096] Subsequently, the main control chip adjusts the first control signal to a high level and the second control signal to a low level, causing the first composite transistor Q1 to switch to the on state and the third composite transistor Q3 to switch to the off state. Based on the voltage values ​​V4 read by WSS_ADC, V5 read by WSS_12V_ADC2, and V6 read by WSS_12V_ADC1, it determines whether there is one or more of the following faults: wheel speed sensor overcurrent fault, wheel speed sensor positive interface short circuit to ground fault, or wheel speed sensor open circuit fault. If the determination result is yes, the main control chip can send a fault signal to the connected controller or other units in the controller. If the determination result is no fault, the main control chip continues to perform self-testing.

[0097] Subsequently, the main control chip adjusts the second control signal to a high-level signal and controls its frequency to a preset frequency. Based on the frequencies of the signals read from WSO_PWM1 and WSO_PWM2, it determines whether a fault has occurred in the third sub-circuit. If the determination indicates a fault exists, the main control chip sends a fault signal to the connected controller or other units within the controller. If the determination indicates no fault exists, the main control chip sends a signal to the connected controller or other units within the controller to indicate that the self-test has passed.

[0098] Understandable. Figure 4 The process described above is merely an example. In actual implementation, the order of the above steps can be adjusted, and only some of the above steps can be performed. This application embodiment does not impose any limitations.

[0099] In some embodiments, the first sub-circuit further includes a third signal output port, which is used to connect to another sampling pin of the main control chip. During the process of the first sub-circuit supplying power to the wheel speed sensor, when the difference between the voltage signal output by the first sampling pin and the voltage signal output by the other sampling pin is greater than a second difference threshold, or when the voltage signal output by the other sampling pin is greater than a sixth preset voltage, the main control chip controls the first and second transistors to disconnect.

[0100] In this embodiment of the application, the aforementioned sampling pin is... Figure 3 The sampling pin WSS_12V_ADC1 is connected to the anode of diode D1 via resistor R18. During the operation of the wheel speed sensor, the main control chip controls the first control signal to a high level and the second control signal to a low level. At this time, the main control chip reads the voltage value V7 through the sampling pin WSS_12V_ADC1 and the voltage value V8 through the sampling pin WSS_12V_ADC2. If the difference between V7 and V8 is less than the second difference threshold, the main control chip confirms that there is no overcurrent fault on the positive interface WSS+ side of the wheel speed sensor. If the difference between V7 and V8 is greater than the second difference threshold, the main control chip confirms that there is an overcurrent fault on the positive interface WSS+ side of the wheel speed sensor. Further, the main control chip adjusts the first control signal to a low level, controls the first transistor in the first composite transistor Q1 to disconnect the second transistor Q2, thereby disconnecting the power supply to the wheel speed sensor. The second difference threshold can be exemplarily 0.5V.

[0101] Optionally, if the difference between V7 and V8 is less than the fourth difference threshold, the main control chip has no overcurrent fault and no overcurrent risk. If the difference between V7 and V8 is greater than the fourth difference threshold but less than the second difference threshold, the main control chip determines that the wheel speed sensor has an overheating risk. In this case, the main control chip can send a warning signal to the connected controller or other units in the controller, so that the driver can understand the status of the vehicle sensors in a timely and accurate manner, improving the driver's driving confidence. The fourth difference threshold can be exemplarily set to 0.3V.

[0102] In this embodiment, the main control chip can also determine whether there is an overcurrent fault at the negative interface WSS- of the wheel speed sensor by reading the voltage value V9 from the sampling pin WSS_ADC. Specifically, if V9 is less than a sixth preset voltage, it indicates that the negative interface WSS- of the wheel speed sensor is normal. If V9 is greater than the sixth preset voltage, it indicates that there is an overcurrent fault at the negative interface WSS- of the wheel speed sensor, and the main control chip sends a fault signal to the connected controller or other units in the controller. Optionally, the main control chip can also set the first control signal to a low level to disconnect the power supply to the wheel speed sensor. The sixth preset voltage can be exemplarily 5V.

[0103] Figure 5 The following describes a specific process for overcurrent / overheat detection using a controller provided in an embodiment of this application. For a detailed description, please refer to the above text, which will not be repeated here. It should be noted that... Figure 5 The process shown can be executed multiple times during the operation of the wheel speed sensor. For example, the process can be executed periodically to avoid damage to the electronic components in the wheel speed sensor or controller due to overcurrent, resulting in higher stability.

[0104] According to the embodiments of this application, the controller can monitor the operating status of the wheel speed sensor in real time and disconnect the power supply to the wheel speed sensor in a timely manner when there is an overcurrent risk, thereby achieving active current limiting protection for the wheel speed sensor. In summary, the controller provided in the embodiments of this application can achieve overcurrent protection for the wheel speed sensor through both hardware and software, resulting in higher reliability.

[0105] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should 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 controller for vehicle wheel speed detection, characterized in that, The controller is used to connect to the wheel speed sensors of the vehicle. The controller includes a wheel speed detection circuit and a main control chip. The wheel speed detection circuit includes: The first sub-circuit has one end for connecting to one pole of the wheel speed sensor and the other end for connecting to a first power supply. The first sub-circuit is used to connect or disconnect the connection between the wheel speed sensor and the first power supply. The second sub-circuit is used to connect to the other pole of the wheel speed sensor. The second sub-circuit and the first sub-circuit are used to detect open circuit faults and / or short circuit faults in the wheel speed detection circuit. The third sub-circuit has an input terminal for connecting to the wheel speed sensor and two output terminals for connecting to the main control chip. The two output terminals are used to output the level signals corresponding to the wheel speed signals of the wheel speed sensor, and the wheel speed signals include three current signals with different pulse levels.

2. The controller according to claim 1, characterized in that, The first sub-circuit includes a first signal input port, a first transistor, and a second transistor. The first signal input port is used to connect to a control pin of the main control chip. The base of the first transistor is used to connect to the first signal input port. The emitter of the first transistor is used to ground. The collector of the first transistor is used to connect to the base of the second transistor. The emitter of the second transistor is also used to connect to the other end of the first sub-circuit. The collector of the second transistor is used to connect to one end of the first sub-circuit. The main control chip is used to control the on and off of the first transistor, thereby controlling the on and off of the second transistor.

3. The controller according to claim 2, characterized in that, The first sub-circuit further includes a first resistor and a third transistor. The first resistor is connected between the emitter of the second transistor and the other end of the first sub-circuit. The first resistor is also connected between the base and emitter of the third transistor. The collector of the third transistor is grounded. During the process of the wheel speed sensor receiving power from the first power source through the second transistor, when the current flowing through the first resistor is greater than a preset current, the third transistor is turned on to turn off the second transistor.

4. The controller according to claim 2 or 3, characterized in that, The second sub-circuit includes a second signal input port, a composite transistor, and two signal output ports. The second signal input port is used to connect to another control pin of the main control chip, and one pin of the composite transistor is used to connect to the second signal input port. One electrode of the wheel speed sensor is connected to a sampling pin of the main control chip via a signal output port. The main control chip is used to adjust the first control signal input through the first signal input port and to detect the voltage of the sampling pin; and / or The other pole of the wheel speed sensor is used to connect to another sampling pin of the main control chip through another of the signal output ports. The main control chip is also used to adjust the second control signal input through the second signal input port and to detect the voltage of the other sampling pin.

5. The controller according to claim 4, characterized in that, The main control chip is used for: Both the first control signal and the second control signal are controlled to be low-level signals; When the voltage signal output from one of the sampling pins indicates a voltage value greater than a first preset voltage, it is confirmed that one pole of the wheel speed sensor is short-circuited to the first power supply; and / or When the voltage value indicated by the voltage signal output from the other sampling pin is greater than the second preset voltage, it is confirmed that the other pole of the wheel speed sensor is short-circuited to the first power supply.

6. The controller according to claim 5, characterized in that, The main control chip is also used for: When the first control signal is controlled to be low and the second control signal is controlled to be high, if the voltage indicated by the voltage signal output by the other sampling pin is less than the third preset voltage, it is confirmed that the other pole of the wheel speed sensor is short-circuited to ground. When the first control signal is controlled to be high and the second control signal is controlled to be low, if the voltage indicated by the voltage signal output by the other sampling pin is less than the fourth preset voltage, the open circuit fault of the wheel speed sensor is confirmed.

7. The controller according to claim 5, characterized in that, The first sub-circuit further includes a third signal output port, which is used to connect to another sampling pin of the main control chip. The main control chip is also used for: When the first control signal is controlled to be high and the second control signal is controlled to be low, if the voltage value indicated by the voltage signal output by one sampling pin is less than the fifth preset voltage, and the difference between the voltage value indicated by the voltage signal output by one sampling pin and the voltage value indicated by the voltage signal output by another sampling pin is greater than the first difference threshold, it is confirmed that one pole of the wheel speed sensor is short-circuited to ground.

8. The controller according to claim 7, characterized in that, During the process of the first sub-circuit supplying power to the wheel speed sensor, the main control chip is also used for: When the difference between the voltage signal output by one sampling pin and the voltage signal output by another sampling pin is greater than a second difference threshold, or when the voltage signal output by another sampling pin is greater than a sixth preset voltage, the first transistor and the second transistor are controlled to disconnect.

9. The controller according to any one of claims 1 to 8, characterized in that, The third sub-circuit includes two comparators. The non-inverting inputs of the two comparators are connected to the input of the third sub-circuit, and the outputs of the two comparators are respectively connected to the two outputs of the third sub-circuit. The inverting input of one of the two comparators is used to connect to a first reference voltage, and the inverting input of the other comparator is used to connect to a second reference voltage. The first reference voltage corresponds to a current signal of a first pulse level, and the second reference voltage corresponds to a current signal of a second pulse level. The three pulse levels are, in descending order, the first pulse level, the second pulse level, and the third pulse level.

10. An electric vehicle, characterized in that, The electric vehicle includes wheels, wheel speed sensors, and a controller according to any one of claims 1 to 9, wherein the controller is used to connect to the wheel speed sensors, and the wheel speed sensors are used to detect the wheel speed of the wheels.

Images