Vehicle control device

Abstract

To provide a vehicle control device capable of traveling using a motor while avoiding welding of an SMR by determining a drive / stop state of a DC-DC converter.SOLUTION: In a vehicle including an engine, a motor, a clutch that connects / disconnects the engine and the motor, a DC-DC converter, an auxiliary battery connected to the DC-DC converter, a controller, and a NODD connection that connects the controller and the DC-DC converter, when an abnormality occurs in the NODD connection, the controller starts the engine and connects the engine and the motor by the clutch to generate power by the motor, and determines a drive / stop state of the DC-DC converter based on the presence or absence of a rise in the voltage of the auxiliary battery at that time.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present disclosure relates to a vehicle control device. [Background technology]

[0002] Patent Document 1 discloses a technique for starting an engine by a starter while avoiding welding of the SMR when starting by the motor is not possible. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2022-092527 Summary of the Invention [Problem to be solved by the invention]

[0004] A known system (FR1M system) transmits engine output to a motor via a clutch, and the torque assisted by the motor drives the front wheels. In this system, the drive / stop of the DC-DC converter is controlled using a NODD connection that connects the HV-ECU and the DC-DC converter.

[0005] If an abnormality occurs in this NODD wiring, it is not possible to control the drive / stop of the DCDC converter, which may cause welding when connecting / disconnecting the SMR.As a result, if an abnormality occurs in the NODD wiring, it is not possible to connect the SMR and drive using the motor.

[0006] The present disclosure has been made in consideration of the above, and aims to provide a vehicle control device that can drive using a motor while avoiding welding of the SMR by determining the drive / stop state of a DC-DC converter. [Means for solving the problem]

[0007] The vehicle control device of the present disclosure is a vehicle that includes an engine, a motor, a clutch that connects / disconnects the engine and the motor, a DCDC converter, an auxiliary battery connected to the DCDC converter, a control unit, and a NODD connection that connects the control unit and the DCDC converter.When an abnormality occurs in the NODD connection, the control unit starts the engine and connects the engine and the motor with the clutch, thereby generating electricity using the motor, and determines the drive / stop state of the DCDC converter based on whether or not there is an increase in the voltage of the auxiliary battery at that time. [Effects of the Invention]

[0008] According to the present disclosure, when an abnormality occurs in the NODD wiring, by determining the drive / stop state of the DC-DC converter, it is possible to avoid welding of the SMR and continue driving using the motor. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a diagram showing a schematic configuration of a vehicle for realizing a vehicle control device according to an embodiment. [Figure 2] FIG. 2 is a diagram illustrating an example of detailed circuits of a DC-DC converter and an HV-ECU in the vehicle control device according to the embodiment. [Figure 3] FIG. 3 is a diagram illustrating an example of the operation of the circuit illustrated in FIG. [Figure 4] FIG. 4 is a flowchart showing an example of the flow of a vehicle control method executed by the vehicle control device according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] A vehicle control device according to an embodiment of the present disclosure will be described with reference to the drawings. Note that components in the following embodiments include those that are easily replaceable by those skilled in the art, or those that are substantially the same.

[0011] (Vehicle control device) The configuration of a vehicle control device according to an embodiment will be described with reference to Figures 1 to 3. Figure 1 shows a schematic configuration of a vehicle for realizing the vehicle control device according to the embodiment. This vehicle is a hybrid electric vehicle (HEV) equipped with a system (FR1M system) that transmits output from an engine to a motor via a clutch and drives the front wheels with torque assisted by the motor.

[0012] The vehicle 1 includes an engine 11, an alternator 12, a starter 13, an electronically controlled mechanical fan 14, a motor 15, a K0 clutch 16, a K0 clutch solenoid 17, a transmission 18, an EFI-ECU 19, and an auxiliary battery 20. The vehicle 1 also includes a temperature sensor 21, a relay box (R / B) 22, an HV-ECU 23, an electric air conditioner 24, an AC inverter 25, a NODD wiring 26, a PCU 27, a battery pack 28, and a cooling fan 29.

[0013] Here, FIG. 1 illustrates only the components necessary to realize the vehicle control device according to the embodiment from the actual configuration of the vehicle 1, and the other components are not illustrated.

[0014] The engine 11 is a driving source for the vehicle 1. An alternator 12 and a starter 13 are provided on the side of the engine 11. The starter 13 is connected to a start switch provided, for example, inside the vehicle compartment.

[0015] The motor 15 is configured, for example, by a three-phase AC motor. The motor 15 is connected to the engine 11 via a K0 clutch 16. The K0 clutch 16 is used to connect / disconnect the engine 11 and the motor 15. A K0 clutch solenoid 17 operates the K0 clutch 16 under the control of an EFI-ECU 19. The transmission 18 is connected, for example, to a shift lever provided inside the vehicle cabin.

[0016] The EFI (Electrical Fuel Injection)-ECU 19 is an electronic control unit (ECU) whose main components are a microcomputer including a CPU (Central Processing Unit), ROM (Read Only Memory), RAM (Random Access Memory), etc. The EFI-ECU 19 controls, for example, the amount of fuel injection required for ignition of the engine 11.

[0017] The auxiliary battery 20 supplies power to various auxiliary devices. The auxiliary battery 20 is connected to a DC-DC converter 273 via a relay box 22. A temperature sensor 21 detects the temperature of a cable (MG cable) connecting the motor 15 and the inverter 272, and outputs the temperature to the EFI-ECU 19. The relay box (R / B) 22 connects the alternator 12, the starter 13, the auxiliary battery 20, and the DC-DC converter 273.

[0018] The HV (Hybrid)-ECU 23 is an electronic control unit (ECU) whose main components are a microcomputer including a CPU, ROM, RAM, etc. The HV-ECU 23 controls, for example, the operation of the SMR 282. A NODD connection 26 is provided between the HV-ECU 23 and the DC-DC converter 273. The HV-ECU 23 uses this NODD connection 26 to control and monitor the drive / stop of the DC-DC converter 273 (see part A in FIG. 1). The HV-ECU 23 also monitors the voltage of the auxiliary battery 20 (see part B in FIG. 1).

[0019] For example, when an abnormality occurs in the NODD connection 26, the HV-ECU 23 starts the engine 11 and connects the engine 11 and the motor 15 by the K0 clutch 16, thereby generating electricity using the motor 15. Then, the HV-ECU 23 determines whether the DC-DC converter 273 is driven or stopped based on whether or not the voltage of the auxiliary battery 20 increases at that time.

[0020] When the motor 15 generates power and supplies a high voltage (for example, the maximum value of the input voltage (VH)) to the DCDC converter 273, the voltage of the auxiliary battery 20 rises if the DCDC converter 273 is operating. Therefore, if the voltage of the auxiliary battery 20 rises, the HV-ECU 23 determines that the DCDC converter 273 is operating. On the other hand, if the voltage of the auxiliary battery 20 does not rise, the HV-ECU 23 determines that the DCDC converter 273 is stopped.

[0021] The PCU (Power Control Unit) 27 includes an MG-ECU 271, an inverter 272, and a DC-DC converter 273. The MG (Motor Generator)-ECU 271 is an electronic control unit (ECU) whose main components are a microcomputer including a CPU, a ROM, a RAM, etc. The MG-ECU 271 controls the motor 15 via the inverter 272. The inverter 272 includes, for example, a plurality of switching elements, a capacitor, and a resistor. The DC-DC converter 273 converts, for example, power from a battery 281 to a low voltage (for example, 12 V) and supplies the converted power to the auxiliary battery 20, etc.

[0022] The battery pack 28 includes a battery 281, an SMR 282, and a monitoring unit 283. The battery 281 is a secondary battery such as a lithium-ion battery. The SMR (System Main Relay) 282 is a semiconductor relay whose opening and closing is controlled by the HV-ECU 23. The monitoring unit 283 is for monitoring the state of the cooling fan 29. The cooling fan 29 is for cooling the battery pack 28.

[0023] Fig. 2 shows an example of detailed circuits of the DC-DC converter 273 and the HV-ECU 23. Fig. 3 shows an example of the operation of the circuit shown in Fig. 2. The NODD connection 26 connecting the DC-DC converter 273 and the HV-ECU 23 has the following functions.

[0024] (1) A stop command is received from the HV-ECU 23. (2) The status (normal / abnormal) of the 12V charging system (for example, the DC-DC converter 273) is transmitted to the HV-ECU 23.

[0025] (Vehicle control method) The flow of a vehicle control method performed by the vehicle control device according to the embodiment will be described with reference to Fig. 4. Note that the processing described below is mainly performed by the HV-ECU 23, but other control units (such as the EFI-ECU 19 and the MG-ECU 271) may also be involved in the processing as necessary.

[0026] First, the HV-ECU 23 starts the system of the vehicle 1 and determines whether or not there is an abnormality in the NODD connection 26 (step S1). If it is determined in step S1 that there is an abnormality in the NODD connection 26 (Yes in step S1), the HV-ECU 23 starts the starter 13 and engages the K0 clutch 16 (step S2), and generates power with the motor 15 (step S3). At this time, the HV-ECU 23 generates power up to the maximum value of the input voltage of the DC-DC converter 273 (for example, VH=300V).

[0027] Next, the HV-ECU 23 determines whether the voltage of the auxiliary battery 20 is rising (step S4). If it is determined in step S4 that the voltage of the auxiliary battery 20 is rising (Yes in step S4), it can be determined that the DC-DC converter 273 is operating. In this case, the HV-ECU 23 does not connect the SMR 282 (step S5) and causes the vehicle 1 to run on the engine (step S6). At this time, only power generation is performed by the motor 15.

[0028] Here, in step S1, if it is determined that there is no abnormality in the NODD connection 26 (No in step S1), the HV-ECU 23 connects the SMR 282 (step S7) and causes the vehicle 1 to run normally (step S8). Note that "normal running" means that the vehicle 1 runs using torque assisted by the motor 15.

[0029] Furthermore, if it is determined in step S4 that the voltage of the auxiliary battery 20 has not increased (No in step S4), it can be determined that the DC-DC converter 273 is stopped. In this case, the HV-ECU 23 releases the K0 clutch 16 to stop the motor 15 (step S9). Next, the HV-ECU 23 connects the SMR 282 to engage the K0 clutch 16 (step S10), and causes the vehicle 1 to run normally (step S11). At this time, the alternator 12 generates electricity.

[0030] As described above, in the vehicle control method according to the embodiment, when an abnormality occurs in the NODD connection 26, the SMR 282 remains disconnected and the engine 11 is started by the starter 13. In addition, the K0 clutch 16 is engaged to generate electricity with the motor 15, thereby supplying a high voltage to the DC-DC converter 273. In this state, if the voltage of the auxiliary battery 20 increases, it can be determined that the DC-DC converter 273 is operating, and if the voltage does not increase, it can be determined that the DC-DC converter 273 is stopped.

[0031] Therefore, if it is determined that the DC-DC converter 273 is operating, the vehicle 1 is allowed to run normally without connecting the SMR 282. On the other hand, if it is determined that the DC-DC converter 273 is stopped, the K0 clutch 16 is opened to stop the motor 15, the SMR 282 is connected, and the vehicle 1 is allowed to run normally.

[0032] According to the vehicle control device of the embodiment described above, when an abnormality occurs in the NODD connection 26, the drive / stop state of the DC-DC converter 273 is determined based on the voltage of the auxiliary battery 20. This makes it possible to run the vehicle using the motor 15 while avoiding welding of the SMR 282.

[0033] Further advantages and modifications will readily occur to those skilled in the art. Thus, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described above. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents. [Explanation of symbols]

[0034] 1 vehicle 11 Engine 12 Alternator 13 Starter 14 Electric Mecha Fan 15 Motor 16 K0 clutch 17 K0 clutch solenoid 18 Transmission 19 EFI-ECU 20 Auxiliary battery 21 Temperature sensor 22 Relay box (R / B) 23 HV-ECU 24 Electric air conditioner 25 AC inverter 26 NODD wiring 27 PCU 271 MG-ECU 272 Inverter 273 DC-DC converter 28 Battery Pack 281 Battery 282 SMR 283 Surveillance Unit 29 Cooling fan

Claims

[Claim 1] A vehicle including an engine, a motor, a clutch for connecting / disconnecting the engine and the motor, a DC-DC converter, an auxiliary battery connected to the DC-DC converter, a control unit, and a NODD connection for connecting the control unit and the DC-DC converter, The control unit When an abnormality occurs in the NODD connection, the engine is started and the engine and the motor are connected by the clutch, thereby generating electricity by the motor; and determining whether the DC-DC converter is in an operating state or not based on whether or not the voltage of the auxiliary battery increases at that time. Vehicle control device.

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