Braking reliability detection device and test method for college student electric formula racing car

Abstract

The present invention belongs to the technical field of electric vehicle braking reliability detection devices, and relates to a braking reliability detection device and a test method for a college student electric formula racing car. The braking reliability detection device includes a braking system pressure sensor, a Hall current sensor, a threshold judgment circuit, a system key signal protection circuit, a logic judgment circuit, a 500ms delay circuit, a fault latch circuit, a safety circuit control circuit, a 10s delay reset circuit, and a power supply voltage stabilization circuit. The braking reliability detection device for a college student electric formula racing car provided by the present invention can disconnect the safety circuit and the high voltage when emergency braking and current output conflict, and protect the motor. At the same time, the device can reset itself after 10s of disconnection, and the driver can power on again to avoid affecting the normal driving of the racing car due to the triggering of the detection device.

Description

Technical Field

[0001] The invention belongs to the technical field of electric vehicle braking reliability detection devices, and relates to a braking reliability detection device and a testing method for a college student electric formula racing car. Background Art

[0002] The existing brake reliability detection device for college student electric formula racing requires the high voltage system to be powered off and the safety circuit must be disconnected until the main switch of the low voltage system is powered on again when emergency braking occurs and the power transmitted to the motor is greater than or equal to a specific threshold. However, during the race, since the driver cannot power on the main switch of the low voltage system by himself, there will be a problem. If the detection device is not effective due to unreliable signal interference of the system or driver's operating error, the safety circuit is disconnected and the high voltage system is powered off, if the car fails to start within a period of time, the race will be forced to end, thus affecting the race results. Therefore, a device is needed to automatically reset the low voltage system when emergency braking and the power transmitted to the motor are greater than or equal to the threshold, that is, when the fault disappears, so that the car can be restarted. Summary of the invention

[0003] The present invention provides a brake reliability detection device for a college student electric formula racing car with a ten-second self-reset function, which solves the problem that the existing device is triggered by mistake, thereby causing the racing car to be unable to start again by itself.

[0004] The technical solution of the present invention to solve the above problem is: a brake reliability detection device for college student electric formula racing car with ten-second self-reset, which is special in that:

[0005] Including brake system pressure sensor, Hall current sensor, threshold judgment circuit, system key signal protection circuit, logic judgment circuit, 500ms delay circuit, fault latch circuit, safety loop control circuit, 10s delay reset circuit, power supply voltage stabilization circuit;

[0006] The brake system pressure sensor and the Hall current sensor are respectively connected to the threshold judgment circuit, which compares and judges the voltage signals transmitted by the brake system pressure sensor and the Hall current sensor with the reference voltage. The threshold judgment circuit and the system key signal protection circuit are respectively connected to the logic judgment circuit, and the logic judgment circuit is connected to the 500ms delay circuit, and the 500ms delay circuit is connected to the fault latch circuit. The 10s delay reset circuit is connected to the fault latch circuit, and the fault latch circuit feeds back the signal to the 10s delay reset circuit. The fault latch circuit is connected to the safety circuit control circuit, and the safety circuit control circuit controls the on and off of the safety circuit to achieve the purpose of controlling the on and off of the high-voltage circuit. The power supply stabilizing circuit supplies power to the threshold judgment circuit, the system key signal protection circuit, the logic judgment circuit, the 500ms delay circuit, the fault latch circuit, the safety circuit control circuit and the 10s delay reset circuit.

[0007] Furthermore, the above-mentioned threshold judgment circuit includes an LM393 voltage comparator and related voltage-dividing resistors and potentiometers. The Hall current sensor voltage signal or the brake pressure sensor voltage signal is input from the same-phase end of the voltage comparator, and the threshold voltage signal after voltage division by the resistor and the potentiometer is input from the inverting end of the voltage comparator. When the Hall current sensor voltage signal or the brake pressure sensor voltage signal is greater than the threshold voltage signal, the comparator outputs a high level; when the Hall current sensor voltage signal or the brake pressure sensor voltage signal is less than the threshold voltage signal, the comparator outputs a low level.

[0008] Furthermore, the above-mentioned system key signal protection circuit utilizes the LM393 dual-channel voltage comparator to form a dual-threshold voltage comparator, and realizes the upper and lower threshold voltage settings through the voltage division principle. When the input Hall current sensor voltage signal or the brake pressure sensor voltage signal is higher than the upper threshold voltage or lower than the lower threshold voltage, the dual-limit voltage comparator outputs a high level. When the input Hall current sensor voltage signal or the brake pressure sensor voltage signal is within the normal voltage range, the dual-limit voltage comparator outputs a low level.

[0009] Furthermore, the above-mentioned logic judgment circuit is composed of logic chips such as CD4069, CD4081, CD4071, etc. The logic level signals output by the system key signal protection circuit and the threshold judgment circuit are subjected to AND, OR, and NOT logic operations, and then a fault signal is output to the fault latch circuit and the 500ms delay circuit. When there is a sensor failure or emergency braking occurs and the power transmitted to the motor is greater than or equal to a specific threshold, the fault signal is high level, and it is low level under normal circumstances.

[0010] Further, the above-mentioned 500ms delay circuit includes a CD4081 AND gate logic chip and related capacitors and resistors. When the output signal of the logic judgment circuit is at a high level, AND gate 1 in this circuit outputs a high level and charges the capacitor. When the capacitor reaches 500ms, the capacitor voltage is at a high level, and AND gate 2 outputs a high level; otherwise, it is at a low level.

[0011] Further, the above-mentioned 10s delay reset circuit includes a CD4081 AND gate logic chip, an LM393 voltage comparator, and related PMOS driver transistors, resistors, and capacitors. When the output fault signal of the logic judgment circuit changes from a high level to a low level, the corresponding PMOS driver transistor conducts to charge the capacitor. When the capacitor voltage reaches the threshold voltage set by the LM393, a high-level reset signal is output; otherwise, a low level is output.

[0012] Further, the above-mentioned fault latching circuit includes a CD4043 RS latch chip. The S port of the CD4043 latch inputs the output signal of the logic judgment circuit, and the R port inputs the output signal of the 10s delay reset circuit. When the S port is at a high level and the R port is at a low level, the latch outputs a high level and continues to output a high level after the S port becomes a low level until the 10s delay reset time ends.

[0013] Further, the above-mentioned safety loop control circuit includes a CD4069 inverter logic chip, an SS8050 transistor, a relay, a switching diode 1N4148, and related resistors. When the fault latching circuit outputs a normal signal (low-level signal), the transistor conducts to drive the load end of the relay to close, and the safety loop is turned on. When the fault latching circuit outputs a fault signal (high-level signal), the transistor cuts off and the load end of the relay disconnects, and the safety loop is turned off.

[0014] Further, the above-mentioned power supply voltage stabilization circuit is composed of an LM317 linear voltage regulator and its peripheral circuit to form a power supply voltage stabilization circuit. The output voltage is used to supply power to the remaining modules. At the same time, a potentiometer RP is used to flexibly adjust the output voltage. The output voltage of the voltage stabilization circuit of this product is 5V.

[0015] The present invention also proposes a detection method for a braking reliability detection device of a college student electric formula racing car with ten-second self-reset based on the above, including the following steps:

[0016] Step 1: Obtain the pressure value of the braking oil circuit through a braking pressure sensor, and obtain the DC bus current value of the drive system through a Hall current sensor;

[0017] Step 2, the brake pressure sensor signal and the Hall current sensor signal are input into two threshold judgment circuits through the wiring terminals, and the current signal voltage is compared with the threshold voltage to output two logic signals. At the same time, the brake pressure sensor signal and the Hall current sensor signal are input into two dual-limit voltage comparison circuits, and the current signal voltage is compared with the upper and lower threshold voltages to output two logic signals;

[0018] Step 3, input the four logic signals output in step 2 into a logic judgment circuit composed of an AND gate, an OR gate, and a NOT gate for logic judgment and output a logic judgment signal, and the signal is processed by a 500ms delay circuit to obtain the braking reliability state at this time;

[0019] Step 4: Input the logic judgment signal output by the logic judgment circuit in step 3 into the 10s delay reset circuit to obtain a reset signal, input the reset signal and the logic judgment signal into the fault latch circuit, and the CD4043 chip outputs a control signal corresponding to the safety circuit according to the two signals;

[0020] Step 5: Output the safety loop control signal in step 4 to the safety loop control circuit, and control the open or closed state of the safety loop at this time according to the input signal.

[0021] In addition, the present invention also proposes a brake reliability detection device based on the above-mentioned Formula E racing car, which is special in that it includes the above-mentioned Formula E racing car with ten-second self-reset function.

[0022] The braking reliability detection device is arranged in the cockpit of the racing car. The Hall current sensor and the brake pressure sensor are arranged in the high-voltage bus and the brake oil circuit respectively. The normally open end of the relay on the circuit board of the braking reliability detection device is connected to the safety circuit. The device compares the input Hall current sensor analog voltage signal and the brake pressure sensor analog voltage signal with their corresponding threshold voltages respectively to output logic level signals under different working conditions. The logic circuit of the circuit board determines the current driving state of the racing car and then controls the opening and closing states of the safety circuit switch.

[0023] Advantages of the present invention:

[0024] The brake reliability detection device for a college student electric formula racing car provided by the present invention can disconnect the safety circuit and the high voltage to protect the motor when emergency braking and current output conflict. At the same time, the device can reset itself 10 seconds after disconnection, and the driver can power on again to avoid affecting the normal running of the racing car due to the triggering of the detection device. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a functional module diagram of the present invention;

[0026] Figure 2 It is the overall schematic diagram of the circuit principle of the present invention.

[0027] 1. Braking system pressure sensor, 2. Hall current sensor, 3. System key signal protection circuit, 4. Threshold judgment circuit, 5. Logic judgment circuit, 6. 500ms delay circuit, 7. Fault latch circuit, 8. Safety loop control circuit, 9. 10s delay reset circuit, 10. Power supply voltage stabilization circuit. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention.

[0029] See also Figure 1 The present invention proposes a brake reliability detection device for a college student electric formula racing car with a ten-second self-reset function, comprising a brake system pressure sensor 1, a Hall current sensor 2, a threshold judgment circuit 4, a system key signal protection circuit 3, a logic judgment circuit 5, a 500ms delay circuit 6, a fault latch circuit 7, a safety loop control circuit 8, a 10s delay reset circuit 9, and a power supply voltage stabilization circuit 10.

[0030] The brake system pressure sensor 1 and the Hall current sensor 2 are respectively connected to the threshold judgment circuit 4, which compares and judges the voltage signals transmitted by the brake system pressure sensor 1 and the Hall current sensor 2 with the reference voltage. The threshold judgment circuit 4 and the system key signal protection circuit 3 are respectively connected to the logic judgment circuit 5, and the logic judgment circuit 5 is connected to the 500ms delay circuit 6, and the 500ms delay circuit 6 is connected to the fault latch circuit 7. The 10s delay reset circuit 9 is connected to the fault latch circuit 7, and the fault latch circuit 7 feeds back the signal to the 10s delay reset circuit 9. The fault latch circuit 7 is connected to the safety circuit control circuit 8, and the safety circuit control circuit 8 controls the on and off of the safety circuit to achieve the purpose of controlling the on and off of the high-voltage circuit. The power supply voltage stabilizing circuit 10 supplies power to the threshold judgment circuit 4, the system key signal protection circuit 3, the logic judgment circuit 5, the 500ms delay circuit 6, the fault latch circuit 7, the safety circuit control circuit 8 and the 10s delay reset circuit 9.

[0031] As a preferred embodiment of the present invention, when the voltage signal of the Hall current sensor 2 or the voltage signal of the brake pressure sensor is greater than the threshold voltage signal, the comparator of the threshold judgment circuit 4 outputs a high level; when the voltage signal of the Hall current sensor 2 or the voltage signal of the brake pressure sensor is less than the threshold voltage signal, the comparator of the threshold judgment circuit 4 outputs a low level.

[0032] As a preferred embodiment of the present invention, when the voltage signal of the input Hall current sensor 2 or the voltage signal of the brake pressure sensor is higher than the upper threshold voltage or lower than the lower threshold voltage, the dual-limit voltage comparator of the system key signal protection circuit 3 outputs a high level, and when the voltage signal of the input Hall current sensor 2 or the voltage signal of the brake pressure sensor is within the normal voltage range, the dual-limit voltage comparator outputs a low level.

[0033] As a preferred embodiment of the present invention, the logic judgment circuit 5 performs logic operations on the logic level signals output by the system key signal protection circuit 3 and the threshold judgment circuit 4, and then outputs a fault signal to the fault latch circuit 7 and the 500ms delay circuit. When there is a sensor failure or emergency braking occurs and the power transmitted to the motor is greater than or equal to a specific threshold, the fault signal is a high level, and it is a low level under normal circumstances.

[0034] As a preferred embodiment of the present invention, the 500ms delay circuit 6 includes a CD4081 AND gate logic chip, a capacitor, and a resistor. When the logic judgment circuit 5 outputs a high level signal, the AND gate 1 in the 500ms delay circuit outputs a high level and charges the capacitor. When the capacitor time reaches 500ms, the capacitor voltage is a high level, and the AND gate 2 outputs a high level. Otherwise, it is a low level.

[0035] As a preferred embodiment of the present invention, the 10s delay reset circuit 9 includes a CD4081 AND gate logic chip, an LM393 voltage comparator, a PMOS driver tube, a resistor, and a capacitor; when the fault signal output by the logic judgment circuit 5 changes from a high level to a low level, the PMOS driver tube is turned on to charge the capacitor, and when the capacitor voltage reaches the threshold voltage set by the LM393, a high level reset signal is output, otherwise a low level is output.

[0036] As a preferred embodiment of the present invention, the fault latch circuit 7 includes a CD4043RS latch chip, the S port of the CD4043 latch inputs the output signal of the logic judgment circuit 5, and the R port inputs the output signal of the 10s delay reset circuit 9. When the S port is high and the R port is low, the latch outputs a high level and continues to output a high level after the S port becomes a low level until the 10s delay reset time ends.

[0037] As a preferred embodiment of the present invention, the safety circuit control circuit 8 includes a CD4069 inverter logic chip, an SS8050 transistor, and a relay. When the fault latch circuit 7 outputs a normal signal, the transistor is turned on to drive the load end of the relay to close, and the safety circuit is turned on. When the fault latch circuit 7 outputs a fault signal, the transistor is turned off to disconnect the load end of the relay, and the safety circuit is disconnected.

[0038] As a preferred embodiment of the present invention, the power supply voltage stabilization circuit 10 includes an LM317 linear voltage stabilizer, a potentiometer RP and its peripheral circuits. The output voltage supplies power to other modules, and the potentiometer RP is used to achieve flexible adjustment of the output voltage.

[0039] Example

[0040] A brake reliability detection device for college student electric formula racing car with ten-second self-reset, refer to the functional module diagram of the present invention Figure 1 And circuit schematic diagram Figure 2 As shown, the braking reliability detection device includes a braking system pressure sensor 1, a Hall current sensor 2, a threshold judgment circuit 4, a system key signal protection circuit 3, a logic judgment circuit 5, a 500ms delay circuit 6, a fault latch circuit 7, a safety loop control circuit 8, a 10s delay reset circuit 9, and a power supply voltage stabilization circuit 10.

[0041] The brake system pressure sensor 1 and the Hall current sensor 2 are respectively connected to the threshold judgment circuit 4, and the threshold judgment circuit 4 compares and judges the voltage signals transmitted by the brake system pressure sensor 1 and the Hall current sensor 2 with the reference voltage. The threshold judgment circuit 4 and the system key signal protection circuit 3 are respectively connected to the logic judgment circuit 5, and the logic judgment circuit 5 is connected to the 500ms delay circuit 6, and the 500ms delay circuit 6 is connected to the fault latch circuit 7, and the 10s delay reset circuit 9 is connected to the fault latch circuit 7. At the same time, the fault latch circuit 7 will also have a signal fed back to the 10s delay reset circuit 9, and the fault latch circuit 7 is connected to the safety circuit control circuit 8. The safety circuit control circuit 8 is equivalent to a switch that controls the on and off of the safety circuit to achieve the purpose of controlling the on and off of the high-voltage circuit. The power supply voltage stabilizing circuit 10 is electrically connected to the above-mentioned threshold judgment circuit 4, the system key signal protection circuit 3, the logic judgment circuit 5, the 500ms delay circuit 6, the fault latch circuit 7, the safety circuit control circuit 8 and the 10s delay reset circuit 9 to supply power to them.

[0042] The system key signal protection circuit 3 uses LM393 comparator.

[0043] The threshold judgment circuit 4 uses the LM393 comparator.

[0044] The logic judgment circuit 5 uses the 4081 AND gate chip, the 4069 inverter and the 4071 OR gate chip.

[0045] The fault latch circuit 7 uses a 4043RS latch.

[0046] In this embodiment, the power supply voltage stabilization circuit 10 uses the LM317 linear voltage regulator, which can reduce the external input 12V voltage to 5V for other circuits. The 10s delay reset circuit 9 uses the CD4081 AND gate logic chip, the LM393 voltage comparator chip, and the AO3401 power PMOS tube to realize the AND gate output signal control AO3401 to charge the capacitor for 10s and output a reset high level signal through the LM393 voltage comparator chip.

[0047] The Hall current sensor detects the sensor voltage output corresponding to the trigger current when the transmission power is greater than 5kW. Figure 2 In the schematic diagram, the Hall current sensor signal is input from port 1 of port JP2. The pressure sensor detects the change in the oil pressure of the brake oil circuit during emergency braking and then obtains the brake signal. Figure 2 In the figure, the pressure sensor is input from port 2 of port JP2. The safety circuit enters from port 1 of port JP3 and outputs from port 2. The circuit board power is provided by port JP1. The above are all necessary signal accesses for BSPD. After the Hall current sensor signal and the pressure sensor signal enter the BSPD, they enter IC2A and IC2BLM393 voltage comparators respectively to compare with the reference voltage. The reference voltage of the Hall current sensor and the reference voltage of the pressure sensor are adjusted by potentiometers RP1 and RP2 respectively. When the output voltage of the Hall current sensor is greater than the reference voltage, the IC2A voltage comparator outputs a high level. Similarly, when the output voltage of the brake signal is greater than the reference voltage, the IC2B voltage comparator also outputs a high level. The outputs of the two comparators are judged by the AND gate U1B to output the fault judgment signal, and the delay of 500ms is completed through the resistor R2, the capacitor C1 and the AND gate U1D. Under normal circumstances, the fault signal C output by the AND gate U1B is a low level. When a fault occurs or the conflict signal exceeds 500ms, the OR gate U3A outputs a fault signal F as a high level and enters the S1 end of the U4CD4043RS latch chip. When S1 is high and R1 is low, the Q1 end outputs a high level, driving the relay JK1 to close, causing contacts 3 and 4 to disconnect, that is, the safety circuit is disconnected, and the vehicle enters a safe state. If the fault disappears afterwards, the fault signal F becomes a low level again, but due to the action of the RS latch, when S1 is low and R1 is low, the Q1 end still maintains the previous state, that is, a high level, and the safety circuit is still in a disconnected state. The fault is eliminated after the low-voltage main switch is reclosed, and the safety circuit can be reclosed.

[0048] The Hall current sensor and brake pressure sensor used in the present invention have an output voltage range of 1 to 5V under normal circumstances. When the signal harness is lost and short-circuited to the ground, the output voltage is 0V. When the signal is short-circuited to the power supply, the output signal is 12V, which is different from the normal situation. Figure 2 The lower left corner is the SCS protection circuit. Taking the brake pressure sensor as an example, the two LM393 voltage comparators IC3A and IC3B form a dual threshold voltage comparator with an upper limit voltage of 5V and a lower limit voltage of 1V. Under normal circumstances, the output voltage of the brake pressure sensor is within this range, and the comparator outputs a high level. When the signal line is lost, the signal is short-circuited to the ground, or the power supply is short-circuited, the output is a low level. The same is true for the Hall current sensor signal protection. The two dual-threshold voltage comparators are judged by the AND gate U1A and the NOT gate U2B to obtain the protection signal. Under normal circumstances, the protection signal is low. When any sensor fails, the protection signal is high. At this time, the output fault signal F is high after being judged by the OR gate U3B and enters the S1 end of the U4CD4043RS latch chip. When S1 is high and R1 is low, the Q1 end outputs a high level and drives the relay JK1 to close, causing the 3 and 4 contacts to be disconnected, that is, the safety circuit is disconnected, and the whole vehicle enters a safe state. It is also necessary to reclose the low-voltage main switch or the safety circuit can be reclosed 10s after the fault disappears.

[0049] The device of the present invention realizes the system self-reset function after the fault is cleared for 10 seconds, the Q1 end of the CD4043 latch chip is connected to the 2 port of the CD4081U5A, the 10 port of the CD4081U2C is connected to the 1 port of the CD4069U2A, the 1 port of the LM393 voltage comparator is connected to the R1 reset port of the CD4043, when the fault disappears, the 6 port of the CD4069U2C outputs a low level, the MOS tube AO3401 is turned on to charge the capacitor, and when the capacitor voltage reaches the threshold voltage obtained by the voltage division of the resistor R26 and the potentiometer RP3, the time is exactly 10 seconds, and the LM393 voltage comparator outputs a high level to realize reset.

[0050] A detection method of the above-mentioned college student electric formula racing car braking reliability detection device with ten-second self-reset comprises the following steps:

[0051] Step 1: According to the layout of the brake oil circuit of the whole vehicle and the parameters of the battery box, a brake pressure sensor is used to detect the pressure of the brake oil circuit, and a Hall current sensor is used to detect the DC bus current of the drive system.

[0052] Step 2. In the braking reliability detection device, the brake pressure sensor signal and the Hall current sensor signal are input into two threshold judgment circuits through wiring terminals to compare the current signal voltage with the threshold voltage and output two logic signals. At the same time, the brake pressure sensor signal and the Hall current sensor signal are input into two dual-limit voltage comparison circuits to compare the current signal voltage with the upper and lower threshold voltages and output two logic signals.

[0053] Step 3: Input the four logic signals output in step 2 into the logic judgment circuit composed of AND gate, OR gate and NOT gate for logic judgment and output logic judgment signal. The signal is processed by 500ms delay circuit to obtain the braking reliability status at this time.

[0054] Step 4: Input the logic judgment signal output by the logic judgment circuit in step 3 into the 10s delay reset circuit to obtain a reset signal, input the reset signal and the logic judgment signal into the fault latch circuit, and the CD4043 chip outputs the control signal corresponding to the safety circuit according to the two signals.

[0055] Step 5: Output the safety loop control signal in step 4 to the safety loop control circuit, and control the open or closed state of the safety loop at this time according to the input signal.

[0056] The present invention also provides a college student electric formula racing car, comprising the above-mentioned college student electric formula racing car braking reliability detection device with ten-second self-reset function.

[0057] The braking reliability detection device is arranged in the cockpit of the racing car. The Hall current sensor and the brake pressure sensor are arranged in the high-voltage bus and the brake oil circuit respectively. The normally open end of the relay on the circuit board of the braking reliability detection device is connected to the safety circuit. The device compares the input Hall current sensor analog voltage signal and the brake pressure sensor analog voltage signal with their corresponding threshold voltages respectively to output logic level signals under different working conditions. The logic circuit of the circuit board determines the current driving state of the racing car and then controls the opening and closing states of the safety circuit switch.

[0058] The above descriptions are merely embodiments of the present invention and are not intended to limit the protection scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related system fields, are also included in the protection scope of the present invention.

Claims

1. A brake reliability detection device for college student electric formula racing car with ten-second self-reset, Features: It includes a brake system pressure sensor (1), a Hall current sensor (2), a threshold judgment circuit (4), a system key signal protection circuit (3), a logic judgment circuit (5), a 500ms delay circuit (6), a fault latch circuit (7), a safety circuit control circuit (8), a 10s delay reset circuit (9), and a power supply voltage stabilization circuit (10); The brake system pressure sensor (1) and the Hall current sensor (2) are respectively connected to a threshold judgment circuit (4), the threshold judgment circuit (4) compares and judges the voltage signals transmitted by the brake system pressure sensor (1) and the Hall current sensor (2) with a reference voltage, the threshold judgment circuit (4) and the system key signal protection circuit (3) are respectively connected to a logic judgment circuit (5), the logic judgment circuit (5) is connected to a 500ms delay circuit (6), the 500ms delay circuit (6) is connected to a fault latch circuit (7), and the 10s delay reset circuit (9) is connected to a fault reset circuit (9). The fault latch circuit (7) feeds back a signal to the 10 s time delay reset circuit (9). The fault latch circuit (7) is connected to the safety circuit control circuit (8). The safety circuit control circuit (8) controls the on / off of the safety circuit, thereby achieving the purpose of controlling the on / off of the high-voltage circuit. The power supply voltage stabilizing circuit (10) supplies power to the threshold judgment circuit (4), the system key signal protection circuit (3), the logic judgment circuit (5), the 500 ms time delay circuit (6), the fault latch circuit (7), the safety circuit control circuit (8) and the 10 s time delay reset circuit (9).

2. A brake reliability detection device for a college student electric formula racing car with a ten-second self-reset function according to claim 1, Features: When the voltage signal of the Hall current sensor (2) or the voltage signal of the brake pressure sensor is greater than the threshold voltage signal, the comparator of the threshold judgment circuit (4) outputs a high level; when the voltage signal of the Hall current sensor (2) or the voltage signal of the brake pressure sensor is less than the threshold voltage signal, the comparator of the threshold judgment circuit (4) outputs a low level.

3. A brake reliability detection device for a college student electric formula racing car with a ten-second self-reset according to claim 2, Features: When the voltage signal of the input Hall current sensor (2) or the voltage signal of the brake pressure sensor is higher than the upper threshold voltage or lower than the lower threshold voltage, the dual-limit voltage comparator of the system key signal protection circuit (3) outputs a high level; when the voltage signal of the input Hall current sensor (2) or the voltage signal of the brake pressure sensor is within a normal voltage range, the dual-limit voltage comparator outputs a low level.

4. A brake reliability detection device for a college student electric formula racing car with a ten-second self-reset according to claim 3, Features: The logic judgment circuit (5) performs a logic operation on the logic level signals output by the system key signal protection circuit (3) and the threshold judgment circuit (4), and then outputs a fault signal to the fault latching circuit (7) and the 500 ms delay circuit. When there is a sensor fault or an emergency brake occurs and the power transmitted to the motor is greater than or equal to a specific threshold, the fault signal is at a high level, and in normal situations, it is at a low level.

5. A braking reliability detection device for a Formula SAE car with a ten-second self-reset according to claim 4, characterized in that: The 500 ms delay circuit (6) includes a CD4081 AND gate logic chip, a capacitor, and a resistor. When the signal output by the logic judgment circuit (5) is at a high level, AND gate 1 in the 500 ms delay circuit outputs a high level and charges the capacitor. When the capacitor time reaches 500 ms, the capacitor voltage is at a high level, and AND gate 2 outputs a high level; otherwise, it is at a low level.

6. A braking reliability detection device for a Formula SAE car with a ten-second self-reset according to claim 5, characterized in that: The 10 s delay reset circuit (9) includes a CD4081 AND gate logic chip, an LM393 voltage comparator, a PMOS driver transistor, resistors, and capacitors; When the fault signal output by the logic judgment circuit (5) changes from a high level to a low level, the PMOS driver transistor conducts to charge the capacitor. When the capacitor voltage reaches the threshold voltage set by the LM393, a high-level reset signal is output; otherwise, a low level is output.

7. A braking reliability detection device for a Formula SAE car with a ten-second self-reset according to claim 6, characterized in that: The fault latching circuit (7) includes a CD4043 RS latch chip. The output signal of the logic judgment circuit (5) is input to the S port of the CD4043 latch, and the output signal of the 10 s delay reset circuit (9) is input to the R port. When the S port is at a high level and the R port is at a low level, the latch outputs a high level, and continues to output a high level after the S port becomes a low level until the 10 s delay reset time ends.

8. A braking reliability detection device for a Formula SAE car with a ten-second self-reset according to claim 7, characterized in that: The safety loop control circuit (8) includes a CD4069 inverter logic chip, an SS8050 triode, and a relay. When the fault latching circuit (7) outputs a normal signal, the triode conducts to drive the load end of the relay to close, and the safety loop is turned on. When the fault latching circuit (7) outputs a fault signal, the triode is cut off and the load end of the relay is disconnected, and the safety loop is turned off; The power supply voltage regulation circuit (10) includes an LM317 linear voltage regulator, a potentiometer RP, and its peripheral circuits, outputs a voltage to supply power to the remaining modules, and at the same time uses the potentiometer RP to flexibly adjust the output voltage.

9. A Formula SAE car, characterized in that: It includes the braking reliability detection device for a Formula SAE car with a ten-second self-reset according to any one of claims 1-8.

10. A detection method for a brake reliability detection device for a college student electric formula racing car with a ten-second self-reset, based on the brake reliability detection device for a college student electric formula racing car with a ten-second self-reset according to any one of claims 1 to 8, It is characterized in that The following steps are involved: Step 1: Obtain the pressure value of the brake oil circuit through the brake pressure sensor, and obtain the DC bus current value of the drive system through the Hall current sensor; Step 2, the brake pressure sensor signal and the Hall current sensor signal are input into two threshold judgment circuits through the wiring terminals, and the current signal voltage is compared with the threshold voltage to output two logic signals. At the same time, the brake pressure sensor signal and the Hall current sensor signal are input into two dual-limit voltage comparison circuits, and the current signal voltage is compared with the upper and lower threshold voltages to output two logic signals; Step 3, input the four logic signals output in step 2 into a logic judgment circuit composed of an AND gate, an OR gate, and a NOT gate for logic judgment and output a logic judgment signal, and the signal is processed by a 500ms delay circuit to obtain the braking reliability state at this time; Step 4: Input the logic judgment signal output by the logic judgment circuit in step 3 into the 10s delay reset circuit to obtain a reset signal, input the reset signal and the logic judgment signal into the fault latch circuit, and the CD4043 chip outputs a control signal corresponding to the safety circuit according to the two signals; Step 5: Output the safety loop control signal in step 4 to the safety loop control circuit, and control the open or closed state of the safety loop at this time according to the input signal.

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