A state monitoring circuit for a vehicle steering sampling system

Abstract

The utility model relates to a kind of state monitoring circuit of vehicle steering sampling system, including first resistance, second resistance, current sampling module and control module;One end of first resistance is connected to power supply voltage, and the other end of first resistance is connected to the power supply end of the angle signal acquisition module of vehicle steering sampling system;The same phase input end of current sampling module is connected to one end of first resistance, and the opposite phase input end of current sampling module is connected to the other end of first resistance, one end of second resistance is connected to the output end of current sampling module, the other end of second resistance is connected to the signal input end of control module, and the signal output end of control module is connected to steering control system;The utility model judges whether the power supply current of angle signal acquisition module is abnormal, if abnormal, then through control module control steering control system, the electric power-assisted steering system of vehicle is turned off, and the mode of mechanical assistance is used, to avoid vehicle out of control.

Description

Technical Field

[0001] This utility model relates to the field of vehicle steering control technology, specifically to a status monitoring circuit for a vehicle steering sampling system. Background Technology

[0002] With the rapid development of electrification in the automotive industry, steering control is evolving towards steer-by-wire, placing increasingly higher demands on the power steering control unit (EPSECU). The working principle of EPS is to acquire torque and angle information from the steering wheel, driving a permanent magnet synchronous motor to output torque and thus providing mechanical power steering.

[0003] If the angle acquisition circuit experiences a short circuit or open circuit, the power steering system may not turn in the intended direction when the driver turns the steering wheel, causing the vehicle to lose control. Therefore, the existing technology does not monitor the working status of the angle acquisition system, which means that when the angle acquisition system malfunctions, it cannot shut down the electric power steering system in time and instead uses mechanical power steering to avoid losing vehicle control. Utility Model Content

[0004] In order to solve the technical problems in the prior art, such as the failure to monitor the working status of the angle acquisition system, which leads to the inability to shut down the electric steering system in time when the angle acquisition system malfunctions, this utility model provides a status monitoring circuit for a vehicle steering sampling system.

[0005] The technical solution of this utility model to solve the above-mentioned technical problems is as follows: A status monitoring circuit for a vehicle steering sampling system includes a first resistor, a second resistor, a current sampling module, and a control module. One end of the first resistor is connected to a power supply voltage, and the other end of the first resistor is connected to the power supply terminal of the angle signal acquisition module of the vehicle steering sampling system. The non-inverting input terminal of the current sampling module is connected to one end of the first resistor, and the inverting input terminal of the current sampling module is connected to the other end of the first resistor. One end of the second resistor is connected to the output terminal of the current sampling module, and the other end of the second resistor is connected to the signal input terminal of the control module. The signal output terminal of the control module is connected to the steering control system. The current sampling module is used to acquire the voltage signal across the first resistor and amplify the acquired voltage signal.

[0006] The beneficial effects of this invention are as follows: By using a first resistor connected in series between the power supply and the power supply terminal of the angle signal acquisition module, the operating current of the angle signal acquisition module is collected using the first resistor. Based on Ohm's law, the voltage across the first resistor is collected using a current sampling module, thereby sampling the power supply current of the angle signal acquisition module. The sampled signal is sent to the control module, which determines whether the power supply current of the angle signal acquisition module is abnormal based on the voltage signal output by the current sampling module. If abnormal, the control module controls the steering control system to shut off the electric power steering system and switch to mechanical power steering to avoid loss of vehicle control, thereby improving the safety of vehicle steering control.

[0007] Based on the above technical solution, the present invention can be further improved as follows.

[0008] Furthermore, it also includes a comparator, the inverting input of which is connected to the other end of the second resistor, the non-inverting input of which is connected to a reference voltage, and the output of which is connected to the signal input of the control module.

[0009] The beneficial effect of adopting the above-mentioned further solution is that by using a comparator to compare the output voltage of the current sampling module with a preset reference voltage, when the output voltage of the current sampling module is greater than the preset reference voltage, a high-level voltage signal is output. When the control module detects the high-level voltage signal, it determines that the power supply current of the angle signal acquisition module is abnormal.

[0010] Furthermore, the current sampling module includes a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, and a first operational amplifier; one end of the third resistor is connected to one end of the first resistor, and the other end of the third resistor is connected to the non-inverting input terminal of the first operational amplifier; one end of the fourth resistor is connected to the other end of the first resistor, and the other end of the fourth resistor is connected to the inverting input terminal of the first operational amplifier; one end of the fifth resistor is connected to the inverting input terminal of the first operational amplifier, and the other end of the fifth resistor is connected to the output terminal of the first operational amplifier; one end of the sixth resistor is connected to the non-inverting input terminal of the first operational amplifier, and the output terminal of the first operational amplifier is connected to one end of the second resistor.

[0011] Furthermore, the comparator includes a seventh resistor, an eighth resistor, and a second operational amplifier; one end of the seventh resistor is connected to a DC voltage, the other end of the seventh resistor is connected to one end of the eighth resistor, the other end of the eighth resistor is grounded, one end of the eighth resistor is connected to the non-inverting input of the second operational amplifier, the inverting input of the second operational amplifier is connected to the other end of the second resistor, and the output of the second operational amplifier is connected to the signal input of the control module.

[0012] Furthermore, the eighth resistor is a variable resistor.

[0013] The beneficial effect of adopting the above-mentioned further solution is that by setting the eighth resistor as a variable resistor, the magnitude of the reference voltage can be changed by changing the resistance value of the eighth resistor, thereby adjusting the abnormal threshold of the power supply current of the angle signal acquisition module.

[0014] Furthermore, it also includes a bidirectional Zener diode, one end of which is connected to the other end of the first resistor, and the other end of which is grounded.

[0015] The beneficial effect of adopting the above-mentioned further solution is that by setting a bidirectional Zener diode, the sampling stability of the voltage across the first resistor can be improved.

[0016] Furthermore, it also includes a first capacitor, one end of which is connected to the other end of the first resistor, and the other end of the first capacitor is grounded.

[0017] The beneficial effect of adopting the above-mentioned further solution is that by setting the first capacitor, the AC noise at the other end of the first resistor can be filtered out, thereby improving the sampling accuracy of the voltage across the first resistor.

[0018] Furthermore, it also includes a second capacitor, one end of which is connected to the other end of the second resistor, and the other end of the second capacitor is grounded.

[0019] The beneficial effect of adopting the above-mentioned further solution is that the second capacitor is used to filter out the AC noise at the other end of the second resistor, thereby improving the output stability and accuracy of the current sampling module.

[0020] Furthermore, it also includes a third capacitor, one end of which is connected to the power supply terminal of the current sampling module, and the other end of which is grounded.

[0021] The advantage of adopting the above-mentioned further solution is that it improves power supply stability by using a third capacitor to filter out AC noise at the power supply terminal of the current sampling module.

[0022] Furthermore, the control module is an MCU. Attached Figure Description

[0023] Figure 1 This is a circuit block diagram of the present invention; Figure 2 This is the circuit diagram of the current sampling module; Figure 3 This is the circuit diagram for a comparator.

[0024] The attached diagram lists the components represented by each number as follows: 1. Current sampling module, 2. Comparator, 3. Control module, 4. Steering control system, 5. Angle signal acquisition module. Detailed Implementation

[0025] The principles and features of this utility model are described below with reference to the accompanying drawings. The examples given are only for explaining this utility model and are not intended to limit the scope of this utility model.

[0026] like Figure 1 As shown, this embodiment provides a status monitoring circuit for a vehicle steering sampling system, including a first resistor R1, a second resistor R2, a current sampling module 1, a comparator 2, a bidirectional Zener diode D1, a first capacitor C1, a second capacitor C2, a third capacitor C3, and a control module 3. One end of the first resistor R1 is connected to the power supply voltage, and the other end of the first resistor R1 is connected to the power supply terminal of the angle signal acquisition module 5 of the vehicle steering sampling system. The non-inverting input terminal of the current sampling module 1 is connected to one end of the first resistor R1, and the inverting input terminal of the current sampling module 1 is connected to the other end of the first resistor R1. One end of the second resistor R2 is connected to the output terminal of the current sampling module 1, and the other end of the second resistor R2 is connected to the signal input terminal of the control module 3. The signal output terminal of the control module 3 is connected to the steering control system 4. The current sampling module 1 is used to collect the voltage signal across the first resistor R1 and amplify the collected voltage signal. The control module 3 is an MCU.

[0027] This embodiment of the invention utilizes a first resistor R1 connected in series between the power supply and the power supply terminal of the angle signal acquisition module 5. The first resistor R1 is used to collect the operating current of the angle signal acquisition module 5. Based on Ohm's law, the current sampling module 1 collects the voltage across the first resistor R1, thereby sampling the power supply current of the angle signal acquisition module 5. The sampled signal is sent to the control module 3. The control module 3 determines whether the power supply current of the angle signal acquisition module 5 is abnormal based on the voltage signal output by the current sampling module 1. If abnormal, the control module 3 controls the steering control system 4 to shut down the electric power steering system of the vehicle and adopt a mechanical power steering mode to avoid loss of vehicle control, thereby improving the safety of vehicle steering control.

[0028] One end of the bidirectional Zener diode D1 is connected to the other end of the first resistor R1, and the other end of the bidirectional Zener diode D1 is grounded. By setting the bidirectional Zener diode D1, the sampling stability of the voltage across the first resistor R1 can be improved.

[0029] One end of the first capacitor C1 is connected to the other end of the first resistor R1, and the other end of the first capacitor C1 is grounded. By setting the first capacitor C1, AC noise at the other end of the first resistor R1 can be filtered out, thereby improving the sampling accuracy of the voltage across the first resistor R1.

[0030] One end of the second capacitor C2 is connected to the other end of the second resistor R2, and the other end of the second capacitor C2 is grounded. The second capacitor C2 is used to filter out AC noise at the other end of the second resistor R2, thereby improving the output stability and accuracy of the current sampling module 1.

[0031] One end of the third capacitor C3 is connected to the power supply terminal of the current sampling module 1, and the other end of the third capacitor C3 is grounded. By using the third capacitor C3 to filter out AC noise at the power supply terminal of the current sampling module 1, the power supply stability is improved.

[0032] Figure 2 As shown, the inverting input of comparator 2 is connected to the other end of the second resistor R2, the non-inverting input of comparator 2 is connected to the reference voltage, and the output of comparator 2 is connected to the signal input of control module 3.

[0033] The current sampling module 1 includes a third resistor R3, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, and a first operational amplifier U1. One end of the third resistor R3 is connected to one end of the first resistor R1, and the other end of the third resistor R3 is connected to the non-inverting input of the first operational amplifier U1. One end of the fourth resistor R4 is connected to the other end of the first resistor R1, and the other end of the fourth resistor R4 is connected to the inverting input of the first operational amplifier U1. One end of the fifth resistor R5 is connected to the inverting input of the first operational amplifier U1, and the other end of the fifth resistor R5 is connected to the output of the first operational amplifier U1. One end of the sixth resistor R6 is connected to the non-inverting input of the first operational amplifier U1, and the output of the first operational amplifier U1 is connected to one end of a second resistor R2. The output voltage Vo of the current sampling module 1 is Vo = ViR6 / R3; where Vi represents the voltage across the first resistor R1, R6 represents the resistance value of the sixth resistor, and R3 represents the resistance value of the third resistor. The power supply voltage VCC is a 5V DC voltage.

[0034] The output voltage of the current sampling module 1 is compared with the preset reference voltage by the comparator 2. When the output voltage of the current sampling module 1 is greater than the preset reference voltage, a high-level voltage signal is output. When the control module 3 detects the high-level voltage signal, it determines that the power supply current of the angle signal acquisition module 5 is abnormal.

[0035] like Figure 3As shown, comparator 2 includes a seventh resistor R7, an eighth resistor R8, and a second operational amplifier U2. One end of the seventh resistor R7 is connected to a DC voltage, and the other end of the seventh resistor R7 is connected to one end of the eighth resistor R8. The other end of the eighth resistor R8 is grounded. One end of the eighth resistor R8 is connected to the non-inverting input of the second operational amplifier U2, and the inverting input of the second operational amplifier U2 is connected to the other end of the second resistor R2. The output of the second operational amplifier U2 is connected to the signal input of the control module 3. The eighth resistor R8 is a variable resistor. By making the eighth resistor R8 a variable resistor, the magnitude of the reference voltage can be changed by altering the resistance value of the eighth resistor R8, thereby adjusting the abnormal current threshold of the angle signal acquisition module 5. The DC voltage is 12V; the supply voltage of both the first operational amplifier U1 and the second operational amplifier U2 is 5V.

[0036] The principle of this embodiment is as follows: a current acquisition resistor is connected in series with the power supply terminal VCC of the angle signal acquisition module 5 to convert the current signal into a voltage signal. The current acquisition signal is then amplified by the current sampling module and sent to comparator 2. Comparator 2 compares the amplified voltage with the reference voltage. If the amplified voltage is less than or equal to the reference voltage, it outputs a low-level voltage signal; if the amplified voltage is greater than the reference voltage, it outputs a high-level voltage signal. The MCU collects the high and low level signals output by comparator 2 to determine whether the angle signal acquisition module 5 is working normally. If the MCU collects the signal output by comparator 2 as a high-level signal, then the MCU will determine that the angle signal acquisition module 5 is working abnormally, and will immediately shut down the electronic power steering system and switch to mechanical steering.

[0037] The above are merely preferred embodiments of the present utility model and are not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the concept and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A status monitoring circuit for a vehicle steering sampling system, characterized in that, The system includes a first resistor (R1), a second resistor (R2), a current sampling module (1), and a control module (3). One end of the first resistor (R1) is connected to the power supply voltage, and the other end of the first resistor (R1) is connected to the power supply terminal of the angle signal acquisition module (5) of the vehicle steering sampling system. The non-inverting input terminal of the current sampling module (1) is connected to one end of the first resistor (R1), and the inverting input terminal of the current sampling module (1) is connected to the other end of the first resistor (R1). One end of the second resistor (R2) is connected to the output terminal of the current sampling module (1), and the other end of the second resistor (R2) is connected to the signal input terminal of the control module (3). The signal output terminal of the control module (3) is connected to the steering control system (4). The current sampling module (1) is used to collect the voltage signal across the first resistor (R1) and amplify the collected voltage signal.

2. The status monitoring circuit of the vehicle steering sampling system according to claim 1, characterized in that, It also includes a comparator (2), the inverting input of which is connected to the other end of the second resistor (R2), the non-inverting input of which is connected to a reference voltage, and the output of which is connected to the signal input of the control module (3).

3. The status monitoring circuit of the vehicle steering sampling system according to claim 2, characterized in that, The current sampling module (1) includes a third resistor (R3), a fourth resistor (R4), a fifth resistor (R5), a sixth resistor (R6), and a first operational amplifier (U1). One end of the third resistor (R3) is connected to one end of the first resistor (R1), and the other end of the third resistor (R3) is connected to the non-inverting input terminal of the first operational amplifier (U1). One end of the fourth resistor (R4) is connected to the other end of the first resistor (R1), and the other end of the fourth resistor (R4) is connected to the inverting input terminal of the first operational amplifier (U1). One end of the fifth resistor (R5) is connected to the inverting input terminal of the first operational amplifier (U1), and the other end of the fifth resistor (R5) is connected to the output terminal of the first operational amplifier (U1). One end of the sixth resistor (R6) is connected to the non-inverting input terminal of the first operational amplifier (U1), and the output terminal of the first operational amplifier (U1) is connected to one end of the second resistor (R2).

4. The status monitoring circuit of the vehicle steering sampling system according to claim 3, characterized in that, The comparator (2) includes a seventh resistor (R7), an eighth resistor (R8), and a second operational amplifier (U2); one end of the seventh resistor (R7) is connected to a DC voltage, the other end of the seventh resistor (R7) is connected to one end of the eighth resistor (R8), the other end of the eighth resistor (R8) is grounded, one end of the eighth resistor (R8) is connected to the non-inverting input of the second operational amplifier (U2), the inverting input of the second operational amplifier (U2) is connected to the other end of the second resistor (R2), and the output of the second operational amplifier (U2) is connected to the signal input of the control module (3).

5. The status monitoring circuit of the vehicle steering sampling system according to claim 4, characterized in that, The eighth resistor (R8) is a variable resistor.

6. The status monitoring circuit of the vehicle steering sampling system according to claim 1, characterized in that, It also includes a bidirectional Zener diode (D1), one end of which is connected to the other end of the first resistor (R1), and the other end of which is grounded.

7. The status monitoring circuit of the vehicle steering sampling system according to claim 1, characterized in that, It also includes a first capacitor (C1), one end of which is connected to the other end of the first resistor (R1), and the other end of the first capacitor (C1) is grounded.

8. The status monitoring circuit of the vehicle steering sampling system according to claim 1, characterized in that, It also includes a second capacitor (C2), one end of which is connected to the other end of the second resistor (R2), and the other end of the second capacitor (C2) is grounded.

9. The status monitoring circuit of the vehicle steering sampling system according to claim 1, characterized in that, It also includes a third capacitor (C3), one end of which is connected to the power supply terminal of the current sampling module (1), and the other end of which is grounded.

10. The status monitoring circuit of the vehicle steering sampling system according to claim 1, characterized in that, The control module (3) is an MCU.

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