Control device of vehicle

Abstract

To stabilize the output of AC voltage of a vehicle.SOLUTION: A high-voltage power supply line 21 of a vehicle 10 is connected to: a high-voltage battery 20; a power control unit 22 that controls power of a motor generator 25; and an AC inverter 23 that converts a DC voltage of the high-voltage power supply line 21 into an AC voltage and outputs the AC voltage. When the AC inverter 23 is outputting the AC voltage, the power control unit 22 prohibits the motor generator 25 from starting an engine 11.SELECTED DRAWING: Figure 1

Description

[Technical Field]

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

[0002] The vehicle described in Patent Document 1 is equipped with a power supply port for supplying power to external electrical devices. When the battery's charging rate is equal to or higher than a threshold, the vehicle supplies power stored in the battery to the external devices with the engine stopped. When the battery's charging rate is lower than the threshold, the vehicle operates the engine and supplies power generated by the engine to the external devices. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2022-67839 Summary of the Invention [Problem to be solved by the invention]

[0004] In some hybrid vehicles equipped with an engine and a motor generator, the engine is started by the motor generator. When the motor generator is driven to start the engine, the battery supply voltage drops significantly. Therefore, if the engine is started by the motor generator while power is being supplied to the power supply port, the power output by the inverter to the power supply port may become unstable. [Means for solving the problem]

[0005] A vehicle control device that solves the above problem is a vehicle control device that includes an engine, a battery, a power line connected to the battery, a motor generator connected to the power line via a power control unit and capable of starting the engine, and an AC inverter that converts the DC voltage of the power line into an AC voltage and outputs it, and is configured to perform MG start prohibition control that prohibits MG start, which starts the engine using the motor generator, when the AC inverter is outputting the AC voltage. [Effects of the Invention]

[0006] The vehicle control device has the effect of stabilizing the output of AC voltage. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a diagram illustrating a configuration of an embodiment of a vehicle control device; [Figure 2] 4 is a flowchart of a process executed by the control device. DETAILED DESCRIPTION OF THE INVENTION

[0008] An embodiment of a vehicle control device will be described in detail below with reference to FIGS. <Configuration of vehicle control device> First, the configuration of this embodiment will be described with reference to Fig. 1. A vehicle 10 shown in Fig. 1 is configured as a hybrid vehicle equipped with an engine 11 and a motor generator 25. The vehicle 10 is equipped with a high-voltage battery 20 and an auxiliary battery 30 having an output voltage lower than that of the high-voltage battery 20.

[0009] The auxiliary battery 30 is connected to a low-voltage power supply line 31. In addition to the auxiliary battery 30, a starter motor 32 is also connected to the low-voltage power supply line 31. Although not shown, low-voltage in-vehicle electrical equipment such as lighting of the vehicle 10 is also connected to the low-voltage power supply line 31. The starter motor 32 is drivingly connected to the engine 11 and serves to start the engine 11 by receiving power supplied from the low-voltage power supply line 31.

[0010] The high-voltage battery 20 is connected to a high-voltage power supply line 21. In addition to the high-voltage battery 20, a power control unit 22, an AC inverter 23, and a step-down circuit 24 are also connected to the high-voltage power supply line 21. A motor generator 25 is connected to the power control unit 22. The motor generator 25 functions as a generator that generates power by receiving power from an external source such as the engine 11. It also functions as a motor that generates power in response to power supplied from the high-voltage battery 20 via the high-voltage power supply line 21. The power control unit 22 controls the power exchanged between the high-voltage power supply line 21 and the motor generator 25. The motor generator 25 is drivingly connected to the engine 11 and is configured to be able to operate as a motor for starting the engine 11. The AC inverter 23 converts the DC voltage of the high-voltage power supply line 21 into AC voltage and outputs it to an AC outlet 26. The AC outlet 26 is an outlet for extracting AC voltage to external devices. The step-down circuit 24 steps down the DC voltage of the high-voltage power supply line 21 and outputs it to a low-voltage power supply line 31.

[0011] The vehicle 10 is further equipped with an electronic control unit 40 as a control device. The electronic control unit 40 includes an arithmetic processing unit 41 and a storage device 42. The storage device 42 stores programs and data for vehicle control. The electronic control unit 40 performs various controls of the vehicle 10 by having the arithmetic processing unit 41 execute programs read from the storage device 42. The control of the vehicle 10 performed by the electronic control unit 40 includes control of the engine 11, the power control unit 22, and the AC inverter 23. The electronic control unit 40 is connected to sensors and switches installed in various parts of the vehicle 10. These sensors and switches include a temperature sensor 43 and an AC switch 44. The temperature sensor 43 is a sensor that detects the battery temperature THB, which is the temperature of the high-voltage battery 20. The AC switch 44 is a switch that allows a passenger to manually turn on and off the output of AC voltage from the AC inverter 23 to the AC outlet 26. The electronic control unit 40 operates the AC inverter 23 in response to an ON operation of the AC switch 44, and stops the operation of the AC inverter 23 in response to an OFF operation of the AC switch 44.

[0012] The vehicle 10 configured as described above has two power supply systems: a high-voltage power supply system centered on the high-voltage battery 20 and the high-voltage power supply line 21, and a low-voltage power supply system centered on the auxiliary battery 30 and the low-voltage power supply line 31. The vehicle 10 also has two electric motors, a motor generator 25 and a starter motor 32, as electric motors capable of starting the engine 11.

[0013] <Regarding intermittent operation control of engine 11> As part of the control of vehicle 10, the electronic control unit 40 performs intermittent operation control of the engine 11. The intermittent operation control is a control that automatically stops and restarts the engine 11 according to the driving situation of the vehicle 10 and the charging status of the high-voltage battery 20. For example, the electronic control unit 40 stops the engine 11 while the vehicle 10 is stopped due to signal waiting or the like, and performs control to restart the engine 11 in response to the start of the vehicle 10 as the intermittent operation control. In the case of the vehicle 10 that switches between the electric driving mode and the hybrid driving mode, control to automatically stop and restart the engine 11 in response to the switching of the driving mode may be performed as the intermittent operation control. When automatically restarting during the intermittent operation control, the electronic control unit 40 restarts the engine 11 by the motor generator 25. In the following description, the start of the engine 11 by the motor generator 25 is described as MG start.

[0014] <Regarding the charge and discharge control of the high-voltage battery 20> During the running of the vehicle 10, the electronic control unit 40 performs charge and discharge control of the high-voltage battery 20. The electronic control unit 40 implements the charge and discharge control by controlling the power control unit 22 so that the charging rate of the high-voltage battery 20 becomes the target value. Specifically, when the charging rate of the high-voltage battery 20 is lower than the target value, the electronic control unit 40 controls the power control unit 22 so that the motor generator 25 generates electricity. Also, when the charging rate of the high-voltage battery 20 is higher than the target value, the electronic control unit 40 controls the power control unit 22 to adjust the power generation amount of the motor generator 25 so that the charging rate of the high-voltage battery 20 becomes the target value.

[0015] <Regarding the MG start inhibition control> Next, referring also to FIG. 2, the MG start inhibition control performed by the electronic control unit 40 will be described. FIG. 2 shows a flowchart of the process executed by the electronic control unit 40 for the MG start inhibition control. The electronic control unit 40 executes the process of FIG. 2 as a process repeatedly executed at every predetermined control cycle.

[0016] 2, the electronic control unit 40 first determines whether the AC switch 44 is on in step S100. If the electronic control unit 40 determines that the AC switch 44 is on (S100: YES), the electronic control unit 40 proceeds to step S110, and if the electronic control unit 40 determines that the AC switch 44 is not on, i.e., that the AC switch 44 is off (S100: NO), the electronic control unit 40 proceeds to step S180.

[0017] First, the processing of the electronic control unit 40 when it is determined in step S100 that the AC switch 44 is on (YES) and the process proceeds to step S110 will be described. In step S110, the electronic control unit 40 determines whether the AC switch 44 was off in the previous control cycle. That is, in step S110, the electronic control unit 40 determines whether the AC switch 44 was switched from off to on between the previous control cycle and the current control cycle. If the electronic control unit 40 determines that the AC switch 44 was off in the previous control cycle (S110: YES), the electronic control unit 40 proceeds to step S120. On the other hand, if the electronic control unit 40 determines that the AC switch 44 was not off in the previous control cycle (S110: NO), the electronic control unit 40 skips the processing of steps S120 to S140 and proceeds to step S150.

[0018] In step S120, the electronic control unit 40 determines whether the engine 11 is stopped. If the engine 11 is stopped (S120: YES), the electronic control unit 40 starts the engine 11 using the starter motor 32 in step S130, and then proceeds to step S140. On the other hand, if the engine 11 is not stopped (S120: NO), the electronic control unit 40 skips step S130 and proceeds to step S140. In step S140, the electronic control unit 40 stops the intermittent operation control of the engine 11, and then proceeds to step S150. When the intermittent operation control is stopped, MG start under intermittent operation control is prohibited.

[0019] When the process proceeds to step S150, the electronic control unit 40 determines whether the battery temperature THB is equal to or lower than a predetermined low temperature determination value in step S150. When the electronic control unit 40 determines that the battery temperature THB exceeds the low temperature determination value (S150: NO), the electronic control unit 40 proceeds to step S170. Then, in step S170, the electronic control unit 40 sets a normal target value as the target charging rate, which is the target value for the charging rate of the high-voltage battery 20 in charge / discharge control, and then ends the process of FIG. 2 for the current control cycle. On the other hand, when the electronic control unit 40 determines that the battery temperature THB is equal to or lower than the low temperature determination value (S150: YES), the electronic control unit 40 proceeds to step S160. Then, in step S160, the electronic control unit 40 sets a high target value higher than the normal target value as the target charging rate, and then ends the process of FIG. 2 for the current control cycle.

[0020] Next, the processing of the electronic control unit 40 when it is determined in step S100 that the AC switch 44 is off (NO) and the process proceeds to step S180 will be described. In step S180, the electronic control unit 40 determines whether the AC switch 44 was on in the previous control cycle. That is, in step S180, the electronic control unit 40 determines whether the AC switch 44 was switched from on to off between the previous control cycle and the current control cycle. If the electronic control unit 40 determines that the AC switch 44 was on in the previous control cycle (S180: YES), the electronic control unit 40 resumes intermittent operation control in step S190 and then proceeds to step S170. On the other hand, if it determines that the AC switch 44 was not on in the previous control cycle (S180: NO), the electronic control unit 40 skips step S190 and proceeds to step S170. Note that when the intermittent operation control is resumed, the prohibited MG start is permitted together with the prohibition of the intermittent operation control.

[0021] <Actions and Effects of the Embodiment> The operation and effects of this embodiment will be described. When the AC switch 44 in the vehicle 10 is switched from off to on, the AC inverter 23 operates and starts outputting AC voltage to the AC outlet 26. Meanwhile, in the intermittent operation control of the engine 11, the engine 11 is restarted by MG start. Both the AC inverter 23 and the motor generator 25 receive power through the high-voltage power supply line 21. Therefore, if MG start is performed while the AC inverter 23 is outputting AC voltage, the AC voltage output by the AC inverter 23 may become unstable.

[0022] In contrast, in this embodiment, the electronic control unit 40 prohibits the intermittent operation control when the AC switch 44 is switched from off to on and the AC inverter 23 starts outputting an AC voltage. This prohibits MG start through the restart control. Therefore, the AC voltage output by the AC inverter 23 does not become unstable due to MG start.

[0023] Furthermore, when MG start is prohibited, the electronic control unit 40 starts the engine 11 using the starter motor 32. The starter motor 32 and the AC inverter 23 are connected to different power supply lines. Therefore, even if the engine 11 is started by the starter motor 32, the AC voltage output by the AC inverter 23 is hardly affected.

[0024] The charge / discharge capacity of the high-voltage battery 20 decreases at low temperatures. Therefore, when the high-voltage battery 20 is at a low temperature, the power supplied from the high-voltage battery 20 to the AC inverter 23 may fall below the power required to output a stable AC voltage. In response to this, the electronic control unit 40 of this embodiment sets the target charging rate, which is the target value for the charging rate in charge / discharge control of the high-voltage battery 20, to a charging rate higher than normal when MG start is prohibited and the AC inverter 23 is outputting AC voltage. Therefore, even when the high-voltage battery 20 is at a low temperature, the power supplied to the AC inverter 23 is less likely to be insufficient.

[0025] According to the control device for the vehicle 10 of the present embodiment described above, the following effects can be achieved. (1) When the AC inverter 23 is outputting AC voltage, the electronic control unit 40 performs MG start prohibition control to prohibit MG start, which starts the engine 11 using the motor generator 25. Therefore, the AC voltage output by the AC inverter 23 does not become unstable due to the execution of MG start. Therefore, the control device for the vehicle 10 of this embodiment has the effect of stabilizing the output of AC voltage from the vehicle 10.

[0026] (2) When MG start is prohibited by the MG start prohibition control, the electronic control unit 40 starts the engine 11 using the starter motor 32 connected to the low-voltage power supply line 31, which is separate from the high-voltage power supply line 21. Therefore, the engine 11 can be started while the AC voltage output from the AC inverter 23 is kept stable.

[0027] (3) When MG start is prohibited, the electronic control unit 40 stops the intermittent operation control that automatically stops and restarts the engine 11 depending on the driving conditions of the vehicle 10. Stopping the intermittent operation control reduces the frequency of engine start, making it easier to prohibit MG start.

[0028] (4) When MG start is prohibited by the MG start prohibition control and the high-voltage battery 20 is in a low temperature state, the electronic control unit 40 sets the target value of the charging rate of the high-voltage battery 20 in the charge / discharge control to a charging rate higher than normal. Therefore, even when the charging / discharging capacity of the high-voltage battery 20 is reduced at low temperatures, the supply of power required to output a stable AC voltage to the AC inverter 23 is less likely to be insufficient.

[0029] <Correspondence> In the present embodiment described above, the high-voltage power supply line 21 corresponds to the power supply line to which the motor generator 25 is connected via the power control unit 22. The battery connected to the high-voltage power supply line 21 corresponds to the high-voltage battery 20. The electronic control unit 40 corresponds to the control device of the vehicle 10.

[0030] (Other embodiments) The above embodiment can be modified as follows: The above embodiment and the following modifications can be combined with each other within the scope of technical compatibility.

[0031] In the above embodiment, when MG start is prohibited by MG start prohibition control and the high-voltage battery 20 is in a low temperature state, the target value for the charge / discharge control of the high-voltage battery 20 is set to a higher charge rate than normal. When MG start is prohibited by MG braking prohibition control, the AC inverter 23 outputs AC voltage, which tends to increase power consumption in the high-voltage power supply system. Therefore, regardless of the temperature of the high-voltage battery 20, when MG start is prohibited by MG start prohibition control, the target value for the charge / discharge control may be set to a higher charge rate than normal to stabilize the power supply to the AC inverter 23.

[0032] In the above embodiment, the engine 11 is started by the starter motor 32 when MG start is prohibited. However, when MG start is prohibited, the engine may not be started. For example, the engine 11 may be started before the AC inverter 23 starts outputting AC voltage.

[0033] Even when MG start is prohibited, the engine 11 may be automatically restarted by the starter motor 32, so that intermittent operation control can be continued. [Explanation of symbols]

[0034] 10 vehicles 11 Engine 20 High-voltage battery 21 High voltage power line 22 Power Control Unit 23 AC inverter 24 Step-down circuit 25 Motor generator 26 AC outlets 30 Auxiliary battery 31 Low voltage power line 32 Starter motor 40 Electronic Control Unit 41 Processing unit 42 Storage device 43 Temperature Sensor 44 AC switch

Claims

1. A control device for a vehicle including an engine, a battery, a power supply line connected to the battery, a motor generator connected to the power supply line via a power control unit and capable of starting the engine, and an AC inverter that converts a DC voltage of the power supply line into an AC voltage and outputs the AC voltage, When the AC inverter is outputting the AC voltage, MG start prohibition control is performed to prohibit MG start, which starts the engine using the motor generator. Vehicle control device.

2. the vehicle includes a starter motor connected to a low-voltage power supply line separate from the power supply line, When the MG start is inhibited by the MG start inhibit control, the engine is started by the starter motor. The vehicle control device according to claim 1 .

3. An intermittent operation control is performed to automatically stop and restart the engine depending on the running conditions of the vehicle, When the MG start is prohibited by the MG start prohibition control, the intermittent operation control is stopped. The vehicle control device according to claim 1 .

4. 2. The vehicle control device according to claim 1, wherein charge / discharge control of the battery is performed so that the charging rate of the battery becomes a target value, and when the MG start prohibition control prohibits the MG start, a charging rate higher than that in the case of no phase is set as the target value.

5. 2. The vehicle control device according to claim 1, wherein charge / discharge control of the battery is performed to set the charging rate of the battery to a target value, and when MG start is prohibited by the MG start prohibition control and the battery is in a low temperature state, a charging rate higher than in other cases is set as the target value.

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