A switching control system for a vehicle relay

Abstract

The present application belongs to the technical field of relay control, and particularly relates to a switching control system of a vehicle relay, comprising: a control module, a power supply module and a latch module; the control module is used for generating a corresponding control signal according to a starting signal; the power supply module is used for ensuring power supply of the control module and the latch module in a normal working mode or a limping mode of the vehicle; the power supply module is further used for monitoring an operating state of the control module and outputting a state signal according to the operating state; the latch module is used for generating a corresponding driving signal according to the starting signal, the control signal and the state signal; and when the starting signal is valid, the driving signal drives the relay to be closed; when the starting signal is invalid, the driving signal drives the relay to be opened. Compared with the traditional technology, the switching control system of the vehicle relay has low hardware cost, simple and easy-to-implement software strategy and higher reliability.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of relay control, and particularly relates to a switching control system of a vehicle relay. BACKGROUND

[0002] The control of an ignition switch relay is an important unit in a vehicle body electronic control system. In a normal driving process, even if an MCU (microcontroller) fails to normally control output, the output state of the relay needs to be maintained to ensure that the basic function unit of the vehicle body is normally powered, and the Limp-home mode needs to be prevented when the ignition input signal IGN is invalid, so as to ensure the safety of the power supply of the whole vehicle.

[0003] To realize the above functions and safety requirements, a common technical solution currently adopts double MCU control. A main MCU serves as normal logic control of a vehicle body controller to control a power supply relay, and an auxiliary MCU serves as safety redundant backup control. When the main MCU fails, the auxiliary MCU can still normally control the output of the power supply relay.

[0004] Although the traditional technical solution improves the safety of starting power control, it also increases the system cost and the complexity of logic control development. Therefore, the ignition switch control circuit of the vehicle body controller needs to find an optimized Limp-home control circuit to reduce the cost, provide system reliability, and reduce the development complexity. SUMMARY

[0005] In view of the above-mentioned defects of the prior art, the purpose of the present application is to provide a switching control system of a vehicle relay to ensure that even if the main control MCU fails, the relay can be controlled to be turned on or off, and the normal power supply of the whole vehicle is ensured, thereby ensuring the driving safety of the vehicle.

[0006] To realize the above-mentioned purpose and other related purposes, the present application provides a switching control system of a vehicle relay, which comprises a control module, a power supply module and a latch module. The control module is used to generate a corresponding control signal according to a starting signal. The power supply module is used to ensure the power supply of the control module and the latch module in a normal working mode or a Limp-home mode of the vehicle. The power supply module is also used to monitor the running state of the control module and output a state signal according to the running state. The latch module is used to generate a corresponding driving signal according to the starting signal, the control signal and the state signal. When the starting signal is valid, the driving signal drives the relay to be closed. When the starting signal is invalid, the driving signal drives the relay to be disconnected.

[0007] According to an embodiment of the present application, the power supply module comprises a power supply unit and a redundant power supply unit, and the power supply unit and the redundant power supply unit are connected in parallel; an input end of the power supply unit is connected to an external power source, and power supply output ends are connected to the control module and the latch module respectively; and the power supply unit is further configured to monitor the running state of the control module and output the state signal through a signal output end; a first input end of the redundant power supply unit is connected to the external power source, a second input end is connected to an output end of the control module, a third input end is connected to an output end of the latch module, and a power supply output end is connected to the latch module; wherein, in the normal working mode, the power supply unit supplies power to the control module and the latch module; and in the limp mode, the redundant power supply unit supplies power to the latch module.

[0008] According to an embodiment of the present application, the power supply unit further outputs the state signal according to its own running state.

[0009] According to an embodiment of the present application, when the power supply unit monitors that the control module is running abnormally or the power supply unit itself is abnormal, the signal output end of the power supply unit outputs an abnormal state signal, and the vehicle enters the limp mode.

[0010] According to an embodiment of the present application, the power supply unit comprises a first diode, and a negative electrode of the first diode is used as the power supply output end of the power supply unit.

[0011] According to an embodiment of the present application, the redundant power supply unit controls its power supply to the latch module in the limp mode according to the running state of the power supply unit, and the control signal of the control module and / or the driving signal of the latch module.

[0012] According to an embodiment of the present application, the redundant power supply unit comprises: a first PNP-type triode, an emitter of which is connected to an external power source; a first NPN-type triode, a collector of which is connected to a base and a collector of the first PNP-type triode respectively; a second NPN-type triode, a collector of which is connected to a base of the first PNP-type triode, and an emitter of which is grounded; a second diode, a positive electrode of which is connected to a first output end of the latch module, and a negative electrode of which is connected to a base of the second NPN-type triode; a third diode, a positive electrode of which is connected to an output end of the control module, and a negative electrode of which is connected to a base of the second NPN-type triode; a fourth diode, a positive electrode of which is grounded, and a negative electrode of which is connected to the base and the collector of the first NPN-type triode respectively; and a fifth diode, a positive electrode of which is connected to an emitter of the first NPN-type triode, and a negative electrode of which is used as an output end of the redundant power supply unit.

[0013] According to an embodiment of the present application, when the power supply unit is normal, the first diode is turned on and the fifth diode is turned off, and the redundant power supply unit is in a closed state; when the power supply unit is abnormal, and the control module outputs a high-level control signal or the latch module outputs a high-level driving signal, the redundant power supply unit is in a starting state and supplies power to the latch module.

[0014] According to an embodiment of the present application, the control module comprises a first input end and a second input end, the first input end is used for receiving the starting signal, and the second input end is connected with an output end of the latch module; wherein the control signal comprises a first sub-signal, a second sub-signal and a clock signal, the first sub-signal is output to the power supply module and the latch module respectively, and the second sub-signal and the clock signal are output to the latch module.

[0015] According to an embodiment of the present application, the latch module comprises: a signal processing unit, used for receiving the starting signal, the first sub-signal, the clock signal, the state signal and the driving signal and outputting after conversion; a D flip-flop, an SD pin of which is connected with an output end of the power supply module, a D pin of which is used for receiving the second sub-signal, and a CP pin and an RD pin of which are connected with output ends of the signal processing unit; an output end of the D flip-flop comprises a first pin and a second pin, the first pin is used for outputting the driving signal, the second pin is connected with the second input end of the control module and outputs an electrical signal opposite to the driving signal; wherein when the starting signal is valid: in the normal working mode, a CP pin of the D flip-flop triggers a rising edge, SD pin, RD pin and D pin are all set high, and the first pin outputs a high-level driving signal; in the limping mode, the CP pin of the D flip-flop triggers a falling edge, the SD pin and the RD pin are set high, and the first pin still outputs a high-level driving signal; when the starting signal is invalid: in the normal working mode, the CP pin of the D flip-flop triggers a rising edge, the SD pin and the RD pin are set high, the D pin is set low, and the first pin outputs a low-level driving signal; in the limping mode, the SD pin is set high, the RD pin is set low, and the first pin outputs a low-level driving signal.

[0016] According to a specific embodiment of the present application, the signal processing unit comprises: a second PNP triode, whose emitter is connected to the output end of the power supply module; a third NPN triode, whose base is connected to the collector of the second PNP triode, whose collector is respectively used for receiving the clock signal and connected to the CP pin of the D flip-flop, and whose emitter is grounded; a fourth NPN triode, whose collector is connected to the base of the second PNP triode, whose emitter is respectively used for receiving the state signal and connected to the output end of the power supply module, and whose base is connected to the first pin of the D flip-flop; a sixth diode, whose anode is used for receiving the first sub-signal, and whose cathode is connected to the RD pin of the D flip-flop; a seventh diode, whose anode is used for receiving the driving signal, and whose cathode is connected to the RD pin of the D flip-flop; an eighth diode, whose anode is used for receiving the starting signal, and whose cathode is grounded; a ninth diode, whose cathode is connected to the cathode of the eighth diode; a third PNP triode, whose base is connected to the anode of the ninth diode, whose emitter is respectively connected to the collector of the second PNP triode and the base of the third NPN triode, and whose collector is grounded; and a fifth NPN triode, whose base is connected to the collector of the third PNP triode, and whose collector is respectively connected to the cathode of the sixth diode, the cathode of the seventh diode, and the RD pin of the D flip-flop.

[0017] According to a specific embodiment of the present application, the D flip-flop adopts a 74HC74D chip.

[0018] According to a specific embodiment of the present application, the system further comprises a driving module, whose input end is connected to the output end of the latch module, and which is used for controlling the relay to be closed or opened according to the driving signal.

[0019] The present application provides a switching control system for vehicle relays, which can keep the ignition switch relay in a closed state according to the starting signal of the vehicle even if the vehicle enters a limp-home mode after starting, so as to maintain the power supply circuit of the vehicle and avoid safety accidents during the driving of the vehicle. Meanwhile, the ignition switch relay can be opened according to the starting signal of the vehicle in the limp-home mode, so as to make the vehicle stop running, thereby effectively ensuring the safety of the vehicle and personnel. In addition, the switching control system for vehicle relays of the present application is provided with a redundant power supply unit, which can ensure the output of the driving signal for controlling the on-off of the relay even if the power supply unit is abnormal, so as to make the control system have higher reliability.

[0020] Compared with the prior art, the switching control system for vehicle relays of the present application uses a flip-flop to realize the control function and safety requirements, has low cost, simple software strategy, low development complexity, and higher reliability. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 A structure diagram of a specific embodiment of a switch control system of a vehicle relay provided by the present application;

[0022] Figure 2 A circuit topology diagram of a specific embodiment of a power supply module in a switch control system of a vehicle relay provided by the present application;

[0023] Figure 3 A circuit topology diagram of a specific embodiment of a latch module in a switch control system of a vehicle relay provided by the present application;

[0024] Figure 4 A structure diagram of a control system of a conventional vehicle relay provided by the present application. DETAILED DESCRIPTION

[0025] The above and other advantages and effects of the present application will become readily apparent to those of ordinary skill in the art from the following description in conjunction with the accompanying drawings. The present application can be applied to various embodiments without departing from the spirit and scope of the present application. Therefore, the following embodiments and features thereof can be combined with each other without conflict in the case of not departing from the spirit and scope of the present application.

[0026] It should be noted that the diagrams provided in the following embodiments only schematically illustrate the basic concept of the present application, and thus only the components related to the present application are shown in the diagrams, not the number, shape and size of the components when actually implemented. The shape, number and ratio of the components when actually implemented can be arbitrarily changed, and the layout of the components can be more complex.

[0027] First of all, it should be noted that the prior art is briefly described in order to enable those skilled in the art to better understand the present application.

[0028] Please refer to Figure 4 As shown in the figure, the control system of the conventional vehicle relay uses two MCU chips. MCU1 is used as a normal logic controller of a vehicle body controller to control the working state of a power relay K1. MCU2 is used as a safety redundant backup controller to control the closing or opening of the power relay K1 according to a vehicle start signal IGN when MCU1 fails. In the figure, an SBC chip is used as a power supply circuit of the system and is in communication connection with the MCU chip. A power conversion circuit is used as a redundant power supply circuit of the system to supply power to the MCU when the SBC chip fails. An HSD chip is used as a driving module to drive the power relay K1 to close or open.

[0029] The traditional technical solution ensures the driving safety of the vehicle when the MCU fails, but increases the hardware cost of the system and the complexity of the logical control development.

[0030] Therefore, the application designs an optimized limp control circuit for the ignition relay switch control circuit to reduce the cost, provide system reliability, and reduce the development complexity.

[0031] Please refer to Figures 1-3 The control system includes a control module 10, a power supply module 20, and a latch module 30. The control module 10 is used to receive the start signal of the vehicle and output the corresponding control signal to wake up the control system and start working. The power supply module 20 is connected to the power supply of the vehicle and supplies power to the system. Specifically, the power supply module 20 is configured to ensure normal power supply to the control module 10 and the latch module 20 in the normal working mode or the limp mode of the vehicle, to ensure the normal working of the control system and maintain the continuous control of the vehicle relay. In addition, the power supply module 20 can monitor the running state of the control module 10 in real time and output the running state through a state signal to enable the latch module 30 to respond in time. The latch module 30 identifies the start signal of the vehicle, the control signal of the control module 10, and the state signal of the power supply module 20, and outputs the corresponding driving signal to control the working state of the vehicle ignition switch relay.

[0032] Specifically, in application, when the start signal is valid, it indicates that the vehicle ignition starts to drive, and the driving signal output by the latch module 30 drives the ignition switch relay to close, maintaining the normal power supply of the vehicle. When the start signal is invalid, it indicates that the vehicle is parked and the ignition is turned off, and the driving signal output by the latch module 30 drives the ignition switch relay to open, cutting off the power supply circuit of the vehicle. Compared with the traditional control circuit of double MCU chips, the control system in the embodiment has low cost, low development complexity, is simple and efficient, and effectively ensures that the relay is not affected by the MCU failure.

[0033] In the embodiment, the power supply module 20 comprises a power supply unit 21 and a redundant power supply unit 22, and the power supply unit 21 and the redundant power supply unit 22 are connected in parallel. Among them, normally, the control system is powered by the power supply unit 21, and when the power supply unit 21 is abnormal, the redundant power supply unit 22 starts to supply power, that is, in the normal working mode of the vehicle, the power supply unit 21 supplies power to the control module 10 and the latch module 30; in the limp-home mode of the vehicle, the redundant power supply unit 22 supplies power to the latch module 30, and maintains the normal operation of the control system.

[0034] Specifically, in application, the input of the power supply unit 21 is connected to the power supply of the vehicle to obtain electric energy, and the power supply output end is respectively connected to the control module 10 and the latch module 30 to form a power supply loop. And the power supply unit is used to monitor the running state of the control module 10, and outputs the state signal through the signal output end. In the embodiment, the power supply unit can monitor the running state of the control module 10 through the watchdog mechanism, and the control module 10 can be connected through SPI communication. When the control module 10 is abnormal, the power supply unit outputs a low-level state signal. The specific circuit implementation can be, for example: the signal output end of the power supply unit is connected to the ground through a switch, when the control module 10 is abnormal, the control switch is closed, the signal output end is grounded, and the low-level state signal is output; when the control module 10 is normal, the control switch is opened, and the signal output end has no signal output. Further, the power supply unit 21 also outputs a state signal according to its own running state, and when the power supply unit 21 is abnormal, the signal output end outputs a low-level state signal accordingly.

[0035] The first input end of the redundant power supply unit 22 is also connected to the power supply of the vehicle to obtain electric energy, and the second input end and the third input end are respectively connected to the output end of the control module 10 and the output end of the latch module 30, for judging whether it is necessary to intervene in work to maintain the continuous control of the relay according to the control signal of the control module 10 and / or the driving signal of the latch module when the power supply unit 21 is abnormal.

[0036] In a specific embodiment, the power supply unit 21 uses an SBC chip to build a power supply circuit, and a first diode is connected in series on the output side, and the negative electrode of the first diode is used as the power supply output end of the power supply unit 21. The circuit of the redundant power supply unit 22 is as follows Figure 2The shown, including: the second diode D2, the third diode D3, the fourth diode D4, the fifth diode D5, the first PNP type triode T1, the first NPN type triode T2, and the second NPN type triode T3. Among them, the emitter of the first PNP type triode T1 is connected to the power supply of the vehicle, the base is connected with the collector of the second NPN type triode T3, and the collector is connected with the collector of the first NPN type triode T2. The base of the first NPN type triode T2 is connected with the negative electrode of the fourth diode D4, the emitter is connected with the positive electrode of the fifth diode D5, and the base and the collector are also connected in parallel with the resistor R1. The emitter of the second NPN type triode T3 is grounded, and the base is connected with the negative electrode of the second diode D2 and the negative electrode of the third diode D3, respectively. The positive electrode of the second diode D2 is connected with the first output end of the latch module 30, and the positive electrode of the third diode D3 is connected with the output end of the control module 10 to receive the first sub-signal of the control signal. The negative electrode of the fourth diode D4 is grounded, and the negative electrode of the fifth diode D5 is grounded through the resistor R2 and also serves as the output end of the redundant power supply unit 22 to output the working voltage.

[0037] Specifically, in actual application, before the start signal is valid, the vehicle body has been in the wake-up state, for example, triggered by brake, key insertion, door lock and other wake-up sources. At this time, the power supply unit 21 starts normal work, and outputs 4.4V working voltage to the control module 10 and the latch module 30 through the first diode D1 and the resistor R2 of the parallel redundant power supply unit 22. At the same time, since the first diode D1 is turned on at this time, the fifth diode D5 in the redundant power supply unit 22 is cut off, and the control system is powered by the power supply unit 21.

[0038] When the start signal is valid, the control module 10 recognizes the start signal and outputs the first sub-signal to high, the third diode D3 is turned on, causing the second diode D2 to be cut off, and the redundant power supply unit 22 is controlled by the first sub-signal. At the same time, the first sub-signal triggers the second NPN type triode T3 to be turned on through the third diode D3, at this time the base of the first PNP type triode T1 is grounded to meet the conduction condition to trigger the conduction, since the emitter of the first PNP type triode T1 is connected to the power supply of the vehicle, after being turned on, the base of the first NPN type triode T2 is set to high through the resistor R1 and the fourth diode D4, and then the first NPN type triode T2 and the redundant power supply unit 22 complete the power-on. But since the fifth diode D5 is cut off in the normal state of the power supply unit 21, the control system is actually powered by the power supply unit 21.

[0039] However, when the power supply unit 21 is abnormal, the vehicle enters limp mode, at this time the power output end of the power supply unit 21 has no voltage output, therefore, the first diode D1 is cut off, and the redundant power supply unit 22 has completed power-on, at this time the fifth diode D5 is turned on, and a working voltage of 4.4V is output through the resistor R2, and the redundant power supply unit 22 starts to supply power to the latch module.

[0040] Further, when the control module 10 is abnormal, the vehicle enters limp mode, and since the control system has completed power-on, the latch module 30 outputs a high drive signal, the third diode D3 is cut off, and the second diode D2 is turned on. As described above, the redundant power supply unit 22 can be controlled by the drive signal. If the power supply unit 21 is normal, the first diode D1 is turned on, and the fifth diode D5 is cut off, and the power supply unit 21 normally supplies power. If the power supply unit 21 is abnormal, the first diode D1 is cut off, and the fifth diode D5 is turned on, and the redundant power supply unit 22 can still supply power to the latch module 30 according to the drive signal.

[0041] Therefore, the power supply module 20 in the embodiment can complete the power supply output to the control system when the start signal is valid, whether the vehicle is in normal working mode or limp mode, and has high reliability.

[0042] In the embodiment, the control module 20 comprises a first input end for receiving the starting signal and a second input end connected with the output end of the latch module 30 and capable of outputting a corresponding control signal according to the starting signal and / or the driving signal. The control signal comprises a first sub-signal, a second sub-signal and a clock signal, the first sub-signal is output to the power supply module 20 and the latch module 30 respectively, and the second sub-signal and the clock signal are output to the latch module 30. The latch module 30 comprises a signal processing unit 31 and a D flip-flop 32, the signal processing unit 31 outputs after conversion according to the starting signal, the first sub-signal, the clock signal and the state signal and the driving signal. The D flip-flop 32 has a SD pin connected with the output end of the power supply module 20, a D pin for receiving the second sub-signal, a CP pin and a RD pin connected with the output end of the signal processing unit 31. The output end of the D flip-flop 32 comprises a first pin Q and a second pin Q*, the first pin Q is used for outputting the driving signal, and the second pin Q* is connected with the second input end of the control module 10 and outputs an electrical signal opposite to the driving signal. In addition, the VCC pin of the D flip-flop 32 is connected with the output end of the power supply module 20, and the GND pin is grounded. The D flip-flop 32 triggers different working states according to the electrical signals of the CP pin, the SD pin, the RD pin and the D pin to output the corresponding driving signal. Specifically, in actual application, when the starting signal is valid: even if the vehicle is in the normal working mode or the limping mode, the first pin of the D flip-flop can output a high-level driving signal. When the starting signal is invalid: even if the vehicle is in the normal working mode or the limping mode, the first pin of the D flip-flop can output a low-level driving signal, thereby driving the closing and opening of the vehicle ignition switch relay and ensuring the driving safety of the vehicle.

[0043] In a specific embodiment, as shown in Figure 3 the D flip-flop 32 adopts a 74HC74D chip, and the truth table is as follows:

[0044] Table 1, 74HC74D logic function truth table

[0045]

[0046] Among them, H represents high level, L represents low level, X represents any state, ↑ represents low level to high level, that is, rising edge, ↓ represents high level to low level, that is, falling edge, Q n represents repeating the previous state.

[0047] The signal processing unit comprises a second PNP type transistor T4, a third NPN type transistor T5, a fourth NPN type transistor T6, a third PNP type transistor T7, a fifth NPN type transistor T8, and a sixth diode D6, a seventh diode D7, an eighth diode D8, and a ninth diode D9. The second PNP type transistor T4 has its emitter connected to the output of the power supply module 20, its collector connected to the base of the third NPN type transistor T5, and its base connected to the collector of the fourth NPN type transistor T6. The collector of the third NPN type transistor T5 is connected to receive the clock signal through the resistor R3, and is connected to the CP pin of the D flip-flop 32, and its emitter is grounded. The emitter of the fourth NPN type transistor T6 is used to receive the state signal, and is connected to the output of the power supply module 20 through the resistor R4, and its base is connected to the first pin Q of the D flip-flop 32 through the resistor R5. The anode of the sixth diode D6 is used to receive the first sub-signal, the anode of the seventh diode D7 is used to receive the driving signal, and the cathodes of the sixth diode D6 and the seventh diode D7 are connected in parallel to the collector of the fifth NPN type transistor T8, and are connected to the RD pin of the D flip-flop 32 through the resistor R9. In addition, the RD pin of the D flip-flop 32 is also grounded through the resistor R10. The anode of the eighth diode D8 is used to receive the start signal, the anode of the ninth diode D9 is connected to the base of the third PNP type transistor T7, and the cathodes of the eighth diode D8 and the ninth diode D9 are connected in parallel and grounded through the resistor R6. The emitter of the third PNP type transistor T7 is connected to the collector of the second PNP type transistor T4 and the base of the third NPN type transistor T5, and its collector is connected to the base of the fifth NPN type transistor T8 through the resistor R7. The base of the fifth NPN type transistor T8 is also grounded through the resistor R8, its collector is also connected to the RD pin of the D flip-flop 32 through the resistor R8, and its emitter is grounded.

[0048] In addition, the D pin of the D flip-flop 32 receives the second sub-signal through the resistor R13, the second pin Q is connected to the second input of the control module 10 through the resistor R9, and the first pin Q outputs the driving signal through the resistor R12.

[0049] Specifically, in the application, when the start signal is valid, the control system starts to power on, the first sub-signal and the second sub-signal output by the control module 10 are both high, at this time, the second sub-signal is high through the resistance R13 to the D foot of the D flip-flop 32, and the first sub-signal is high through the sixth diode D6, the resistance R9 and the resistance R10, and then to the RD foot of the D flip-flop 32. And because the control system just starts to power on, the D flip-flop has not output the corresponding driving signal, so the first pin Q is low, and the seventh diode D7 and the fifth NPN transistor T8 circuit are not turned on. The SD foot of the D flip-flop is connected to the output end of the power supply module 20 to receive the working voltage of 4.4V, that is, the high-level electrical signal.

[0050] At this time, the D flip-flop 32 meets SD=H, RD=H, D=H, and CP is converted from low level to high level, triggering the rising edge, and according to the logic function truth table in Table 1, the first pin Q of the D flip-flop 32 outputs a high-level driving signal.

[0051] When the control module 10 and / or the power supply unit 21 is abnormal, that is, the vehicle enters the limp mode, the signal output end of the power supply unit 21 outputs a low-level state signal. At the same time, because the control system has completed the power-on, the first pin Q of the D flip-flop 32 is outputting a high-level driving signal, and the driving signal makes the fourth NPN transistor T6 conduct through the resistance R4, so that the base of the second PNP transistor T4 is pulled down to low. Therefore, the second PNP transistor T4 is turned on, and under the working voltage of 4.4V of the power supply module 20, the base of the third NPN transistor T5 is pulled up to high, the third NPN transistor T5 is turned on, and the CP foot of the D flip-flop 32 is grounded to low. When the control module 10 and / or the power supply unit 21 is normal, the signal output end of the power supply unit 21 has no state signal output, and the base of the second PNP transistor T4 is in an open state through the working voltage of 4.4V of the power supply module 20.

[0052] In addition, the high-level driving signal output by the first pin Q makes the seventh diode D7 conduct, and because the start signal is valid and high, the eighth diode D8 conducts and the ninth diode D9 is cut off, so that the third PNP transistor T7 and the fifth NPN transistor T8 cannot be turned on. The driving signal is still high through the seventh diode D7, the resistance R9 and the resistance R10 to the RD foot of the D flip-flop 32, and the working voltage output of 4.4V of the power supply module 20 is still high to the SD foot of the D flip-flop 32.

[0053] Therefore, the D flip-flop 32 meets SD = H, RD = H, D = X, and CP is converted from high level to low level, triggering the falling edge. According to the logic function truth table of Table 1, the first pin Q of the D flip-flop 32 keeps the output of the previous state of the driving signal, still outputs the high level driving signal, and realizes the latching of the driving signal.

[0054] When the vehicle is in the normal working mode, the second sub-signal and the clock signal output by the control module 10 are low when the starting signal is invalid, and the second PNP type transistor T4 is in the off state. At this time, since the starting signal is invalid, the base of the third PNP type transistor T7 is grounded through the ninth diode D9, the third PNP type transistor T7 is turned on, the base of the fifth NPN type transistor T8 is grounded, and the fifth NPN type transistor T8 is turned off. At the same time, the D flip-flop 32 still outputs the high level driving signal, and the RD pin is high level through the seventh diode D7. The control module 10 sets the clock signal high again after one clock cycle, thereby triggering the rising edge of the CP pin of the D flip-flop 32.

[0055] At this time, the D flip-flop 32 meets SD = H, D = L, RD = H, and CP is converted from low level to high level, triggering the rising edge. According to the logic function truth table of Table 1, the first pin Q of the D flip-flop 32 outputs the low level driving signal, thereby controlling the ignition switch relay of the vehicle to be turned off.

[0056] At the same time, the second pin Q* of the D flip-flop 32 feeds back the high level electrical signal to the second input end of the control module 10, and the control module 10 sets the first sub-signal and the clock signal low after receiving the feedback signal, thereby completing the power down of the control system.

[0057] When the vehicle is in the limp mode, the base of the third PNP type transistor T7 is grounded through the ninth diode D9 when the starting signal is invalid, the third PNP type transistor T7 is turned off, and the fifth NPN type transistor T8 is also turned off. The signal output end of the power supply unit 21 outputs the low level state signal, the fourth NPN type transistor T6 is turned on through the high level driving signal, the second PNP type transistor T4 is turned on, the 4.4V working voltage output by the power supply module 20 is divided through resistors R7 and R8, the fifth NPN type transistor T8 is turned on, and then the driving signal output by the D flip-flop is led to the ground, and the RD pin of the D flip-flop 32 is also set low.

[0058] At this time, the D flip-flop 32 meets SD = H, RD = L, D = X, and CP = X. According to the logic function truth table of Table 1, the first pin Q of the D flip-flop 32 can output the low level driving signal, and the ignition switch relay of the vehicle can still be turned off.

[0059] Therefore, the switching control system of the vehicle relay in the embodiment can control the relay to keep closed according to the starting signal of the vehicle in the normal mode or the limp-home mode, thereby ensuring the driving safety of the vehicle, and can also control the relay to be opened according to the starting signal of the vehicle, thereby making the vehicle stop running.

[0060] It should be noted that, after the control system is powered on, if the control module 10 or the power supply unit 21 is abnormal, that is, the vehicle enters the limp-home mode, the latch module 30 can keep the state of the ignition switch relay of the vehicle unaffected, thereby avoiding that the relay is opened during the driving of the vehicle, causing abnormal power supply of the vehicle and causing a safety accident. If the control module 10 or the power supply unit 21 is abnormal before the control system is powered on, the control system is directly detected and maintained, and the fault is eliminated.

[0061] Further, in the embodiment, the control system further comprises a driving module 40, which controls the relay to be closed or opened according to the driving signal of the latch module 30, and no more requirements are made.

[0062] In summary, the switching control system of the vehicle relay is provided to ensure that the working state of the ignition switch relay of the vehicle during driving is not affected by the fault of the control module, even if the vehicle enters the limp-home mode after starting, the ignition switch relay can be kept in the closed state according to the starting signal of the vehicle, so as to maintain the power supply loop of the vehicle and avoid safety accidents during driving of the vehicle. Meanwhile, the ignition switch relay can be opened according to the starting signal of the vehicle in the limp-home mode, so as to make the vehicle stop running, thereby effectively ensuring the safety of the vehicle and personnel. In addition, the switching control system of the vehicle relay of the application further comprises a redundant power supply unit, even if the power supply unit is abnormal, the output of the driving signal for controlling the relay can be ensured, so that the control system has higher reliability.

[0063] Compared with the prior art, the switching control system of the vehicle relay of the application uses a flip-flop to realize the control function and safety requirements, has low cost, simple software strategy and low development complexity, and has higher reliability.

[0064] The above embodiments only exemplarily illustrate the principles and effects of the application, and are not used to limit the application. Any person skilled in the art can modify or change the above embodiments without departing from the spirit and category of the application. Therefore, all equivalent modifications or changes completed by those skilled in the art without departing from the spirit and technical thought of the application should be covered by the claims of the application.

[0065] In the description, numerous specific details are provided, such as examples of components and / or methods, to provide a thorough understanding of embodiments of the present application. Applicants have provided this description along with the example to illustrate embodiments of the present application and to enable others skilled in the art to make and use the application. Persons skilled in the art will understand, however, that the application can be practiced without many of the specific details described herein, that work or elements can take different forms, dimensions, or positions, and that individual features can be absent from the example. In some instances, well-known structures have not been described in detail in order to avoid obscuring the concepts of the present application.

[0066] References throughout this specification to "one embodiment," "an embodiment," or "the embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the application, and can not necessarily be present in all embodiments. Thus, the appearances of the phrases "in one embodiment," "in an embodiment," or "in some embodiments" in various places throughout this specification are not necessarily referring to the same embodiment. Furthermore, the particular features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. It will be appreciated that, for clarity and understanding, the application is described and illustrated in terms of specific embodiments and in connection with the figures.

[0067] It will also be appreciated that one or more of the elements, components, modules, and / or modules illustrated in the drawings can also be implemented in a more integrated or a more separated manner, or even removed and provided as a standalone device, even if not specifically mentioned herein.

[0068] In addition, unless explicitly stated otherwise, any directional or positional adjectives, such as "front," "back," "up," "down," "top," "bottom," "side," etc., are used with reference to the orientation of the figure being described. In addition, unless specifically stated otherwise, the use of the term "or" in the context of this document is used as the inclusive or, i.e., the term "A or B" means "A, B, or both." Further, the use of the term "a" or "an" are open ended, meaning one or more of the referenced item is present with the understanding that the use of the terms "a" or "an" indicate the presence of at least one of the item and redundancy is excluded by the disclosure of one or more of the items with an "or" between. The disclosure of the item in the exemplary configuration with "one of X, Y and Z" does not mean that there is one X, one Y and one Z, or that the item can only be one of X, Y or Z. It means there can be "one of X, or there can be one of Y; or there can be one of Z; or any combination thereof.

[0069] As used in the description of the application and throughout the claims that follow, unless otherwise indicated, the phrase "one," "an," and "the" include plural references. Also, as used in the description of the application and throughout the claims that follow, unless otherwise indicated, the phrase "in" means "in" and "on."

[0070] The above description of the illustrated embodiments of the application (including what is described in the abstract) is not intended to be exhaustive or to limit the application to the precise forms disclosed. While specific embodiments of, and examples for, the application are described herein for illustrative purposes, various equivalent modifications are possible within the spirit and scope of the application, as those skilled in the relevant art will recognize and appreciate. As indicated, these modifications can be made to the above-described embodiments and yet the application will remain within the scope of the application. Accordingly, while the application is susceptible to various modifications and alternative forms, specific embodiments and examples thereof have been shown and described in detail herein. It should be understood, however, that the application is not to be limited to the particular embodiments or examples disclosed, but to include all possible embodiments which would be within the scope of the above description.

[0071] The systems and methods have been described generally herein as facilitating an understanding of the details of the application. Moreover, various specific details have been given in order to provide a thorough understanding. It will be appreciated, however, that one of ordinary skill in the relevant art will recognize and appreciate that embodiments of the application can be practiced without one or more of the specific details, or with other devices, systems, assemblies, methods, components, materials, parts, and the like. In other instances, well-known structures, materials, and / or operations have not been shown or described in detail in order to avoid obscuring aspects of embodiments of the application.

[0072] Accordingly, although the application has been described in reference to the therefore, many modifications can be made to adapt a particular situation or material to the essential scope and spirit of the present application. The application is not intended to be limited to the particular forms shown, but this application is to cover all modifications, equivalents, and alternatives falling within the scope of the application as defined by the following claims.

Claims

1. A switching control system for a vehicle relay, characterized by, The application relates to a power supply module for a vehicle, which comprises a control module, a power supply module and a latch module. The control module is used for generating corresponding control signals according to start signals. The power supply module is used for ensuring power supply of the control module and the latch module in a normal working mode or a limp mode of the vehicle, and is further used for monitoring the running state of the control module and outputting a state signal according to the running state. The latch module is used for generating corresponding driving signals according to the start signals, the control signals and the state signal, and driving a relay to be closed when the start signals are valid, and driving the relay to be disconnected when the start signals are invalid. The power supply module comprises a power supply unit and a redundant power supply unit, and the power supply unit and the redundant power supply unit are connected in parallel. The input end of the power supply unit is connected with an external power supply, the power supply output end is connected with the control module and the latch module respectively, and the power supply unit is further used for monitoring the running state of the control module and outputting the state signal through a signal output end. The first input end of the redundant power supply unit is connected with the external power supply, the second input end is connected with the output end of the control module, the third input end is connected with the output end of the latch module, and the power supply output end is connected with the latch module. In the normal working mode, the power supply unit supplies power to the control module and the latch module, and in the limp mode, the redundant power supply unit supplies power to the latch module. The control module comprises a first input end and a second input end, the first input end is used for receiving the start signals, and the second input end is connected with the output end of the latch module. The control signals comprise a first sub-signal, a second sub-signal and a clock signal, the first sub-signal is output to the power supply module and the latch module respectively, and the second sub-signal and the clock signal are output to the latch module. The latch module comprises: A signal processing unit is used for receiving the start signals, the first sub-signal, the clock signal, the state signal and the driving signal, and outputting after conversion. A D flip-flop is connected with the output end of the power supply module through an SD pin, a D pin is used for receiving the second sub-signal, a CP pin and an RD pin are connected with the output end of the signal processing unit, the output end of the D flip-flop comprises a first pin and a second pin, the first pin is used for outputting the driving signal, the second pin is connected with the second input end of the control module and outputs an electrical signal opposite to the driving signal. The power supply unit further outputs the state signal according to the running state of the power supply unit.

2. The switching control system of a vehicle relay according to claim 1, characterized by, When the control module runs abnormally or the power supply unit itself supplies power abnormally, the signal output end of the power supply unit outputs an abnormal state signal, and the vehicle enters the limp mode.

3. The switching control system of a vehicle relay according to claim 2, characterized by, The power supply unit comprises a first diode, and the negative electrode of the first diode is used as the power supply output end of the power supply unit.

4. The switching control system of a vehicle relay according to claim 1, characterized by, ​ 5. The switching control system of a vehicle relay according to claim 4, characterized by The redundant power supply unit supplies power to the latch module in the limp mode according to the operating state of the power supply unit and the control signal of the control module and / or the driving signal of the latch module.

6. The switching control system of a vehicle relay according to claim 5, wherein The redundant power supply unit comprises: a first PNP triode, whose emitter is connected to an external power supply; a first NPN triode, whose collector is connected to the base of the first NPN triode and the collector of the first PNP triode; a second NPN triode, whose collector is connected to the base of the first PNP triode and whose emitter is grounded; a second diode, whose anode is connected to the first output terminal of the latch module and whose cathode is connected to the base of the second NPN triode; a third diode, whose anode is connected to the output terminal of the control module and whose cathode is connected to the base of the second NPN triode; a fourth diode, whose anode is grounded and whose cathode is connected to the base and collector of the first NPN triode; a fifth diode, whose anode is connected to the emitter of the first NPN triode and whose cathode is used as the output terminal of the redundant power supply unit.

7. The switching control system of a vehicle relay according to claim 6, characterized by When the power supply unit is normal, the first diode is turned on, causing the fifth diode to be turned off, and the redundant power supply unit is in the off state; when the power supply unit is abnormal, and the control module outputs a high-level control signal or the latch module outputs a high-level driving signal, the redundant power supply unit is in the start state and supplies power to the latch module.

8. The switching control system of a vehicle relay according to claim 1, characterized by, When the start signal is valid: in the normal working mode, the CP pin of the D flip-flop triggers a rising edge, the SD pin, the RD pin and the D pin are all set high, and the first pin outputs a high-level driving signal; in the limp mode, the CP pin of the D flip-flop triggers a falling edge, the SD pin and the RD pin are set high, and the first pin still outputs a high-level driving signal. When the start signal is invalid: in the normal working mode, the CP pin of the D flip-flop triggers a rising edge, the SD pin and the RD pin are set high, the D pin is set low, and the first pin outputs a low-level driving signal; in the limp mode, the SD pin is set high, the RD pin is set low, and the first pin outputs a low-level driving signal. The signal processing unit comprises:

9. The switching control system of a vehicle relay according to claim 8, characterized by, a second PNP triode, whose emitter is connected to the output terminal of the power supply module; a third NPN triode, whose base is connected to the collector of the second PNP triode, whose collector is used to receive the clock signal and is connected to the CP pin of the D flip-flop, and whose emitter is grounded; a fourth NPN triode, whose collector is connected to the base of the second PNP triode, whose emitter is used to receive the state signal and is connected to the output terminal of the power supply module, and whose base is connected to the first pin of the D flip-flop; a sixth diode, whose anode is used to receive the first sub-signal and whose cathode is connected to the RD pin of the D flip-flop; a seventh diode, whose anode is used to receive the driving signal and whose cathode is connected to the RD pin of the D flip-flop; an eighth diode, whose anode is used to receive the start signal and whose cathode is grounded; a ninth diode, whose cathode is connected to the cathode of the eighth diode. ​ A third PNP type triode, the base thereof is connected with the anode of the ninth diode, the emitter thereof is connected with the collector of the second PNP type triode and the base of the third NPN type triode respectively, and the collector thereof is connected with the ground treatment; A fifth NPN type triode, the base thereof is connected with the collector of the third PNP type triode, the collector thereof is connected with the negative electrode of the sixth diode, the negative electrode of the seventh diode and the RD pin of the D flip-flop respectively.

10. The switching control system of a vehicle relay according to claim 9, wherein The D flip-flop adopts a 74HC74D chip.

11. The switching control system of a vehicle relay according to claim 1, characterized by, Further comprising: A driving module, the input end of which is connected with the output end of the latch module, for controlling the relay to be closed or opened according to the driving signal.

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