JP2019098805A - Hybrid vehicle - Google Patents

Abstract

To travel continuously in low temperatures.SOLUTION: A hybrid vehicle controls an engine and a drive device so as to travel in plural travel modes that includes a hybrid travel where the vehicle travel with the engine operated and a motor travel where the vehicle travels on motor power with the engine unoperated. In the vehicle, in a case where an outside temperature is equal to or lower than a given temperature that is higher, by 1°C, than a lower limit temperature within a guaranteed temperature range of the drive device while traveling in the motor travel mode, the engine and drive device are controlled so that the engine is started.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a hybrid vehicle, and more particularly to a hybrid vehicle including an engine, a motor, and a drive device.

  Conventionally, as a hybrid vehicle of this type, a hybrid vehicle has been proposed that includes an engine, a motor (first motor / generator), and a drive device (first inverter) (see, for example, Patent Document 1). The motor motorizes the engine. The drive device drives a motor. In this vehicle, when a request to start the engine is made, the motor is used to motorize the engine to start.

2017-166463 gazette

  In the above-described hybrid vehicle, when traveling in the motor travel mode in which the operation of the engine is stopped and the vehicle travels with power from the motor, if the temperature of the drive falls below a guaranteed temperature at which proper operation is guaranteed. The drive will not be able to drive the motor and the motor will not be able to motor the engine and start the engine. If the engine can not be started and traveling in the motor traveling mode continues, the storage amount of the battery for supplying electric power to the motor will be depleted, making it difficult to continue traveling.

  The hybrid vehicle of the present invention is mainly intended to continue traveling at low temperatures.

  The hybrid vehicle of the present invention adopts the following means in order to achieve the above-mentioned main object.

The hybrid vehicle of the present invention is
With the engine,
A motor for motoring the engine;
A drive device for driving the motor;
A plurality of travel modes including a hybrid travel mode in which the engine and the motor travel with power from the motor with the operation of the engine, and motor travel in which the operation of the engine is stopped and travels with the power from the motor A control device that controls the engine and the drive device to travel;
A hybrid vehicle comprising
The control device is configured to start the engine and the engine so as to start the engine when the outside air temperature is equal to or lower than a predetermined temperature higher by 1 ° C. than the lower limit temperature of the drive device during the traveling in the motor traveling mode. Control the drive and
Make it a gist.

  In the hybrid vehicle according to the present invention, the engine and the drive unit are configured to start the engine when the outside temperature is equal to or lower than a predetermined temperature higher by 1 ° C. than the lower limit temperature of the drive device. And control. As a result, the motor can start motoring the engine before the drive device becomes lower than or equal to the lower limit temperature of the guaranteed temperature range. Thus, it is possible to travel in the hybrid travel mode, and travel can be continued even at low temperatures.

  In the hybrid vehicle according to the present invention, the control device prohibits the transition from the hybrid travel mode to the motor travel mode when the outside temperature is lower than the predetermined temperature during traveling in the hybrid travel mode. The engine and the motor may be controlled to continue traveling in the hybrid traveling mode. In this way, it is possible to suppress transitioning from the hybrid travel mode to the motor travel mode and being unable to continue travel when the outside air temperature is equal to or lower than the predetermined temperature.

FIG. 1 is a configuration diagram schematically showing a configuration of a hybrid vehicle 20 as an embodiment of the present invention. 6 is a flowchart illustrating an example of an EV travel time processing routine executed by the CPU of the electronic control unit 70. 10 is a flowchart showing an example of an HV traveling process routine executed by the CPU of the electronic control unit 70;

  Next, modes for carrying out the present invention will be described using examples.

  FIG. 1 is a block diagram schematically showing the configuration of a hybrid vehicle 20 as an embodiment of the present invention. The hybrid vehicle 20 according to the embodiment includes an engine 22, a motor 30, an inverter 32, a clutch 36, a transmission 40, a battery 60, and an electronic control unit 70, as shown.

  The engine 22 is configured as an internal combustion engine that outputs power using gasoline or fuel as fuel.

  The motor 30 is configured, for example, as a synchronous generator motor.

  The inverter 32 includes a plurality of switching elements (for example, IGBTs), and is connected to the motor 30 and to the power line 61. The inverter 32 has a plurality of switching elements controlled by the electronic control unit 70. The motor 30 is rotationally driven by such switching control.

  The clutch 36 is configured, for example, as a hydraulically driven friction clutch, and performs connection and disconnection between the crankshaft 23 as an output shaft of the engine 22 and the rotation shaft of the motor 30.

  The transmission 40 is connected to an input shaft 41 and a drive shaft 46 connected to the rotation shaft of the motor 30, and has a plurality of planetary gears and a plurality of hydraulically driven friction engagement elements (clutch, brake) . The transmission 40 transmits power between the input shaft 41 and the drive shaft 46 by forming a forward gear and a reverse gear from the first gear to the sixth gear by engagement and disengagement of the plurality of frictional engagement elements. The drive shaft 46 is connected to the drive wheels 50 a and 50 b via an axle 56 and a differential gear 57.

  The battery 60 is configured, for example, as a lithium ion secondary battery, and is connected to the power line 61 together with the inverter 32.

  Although not shown, the electronic control unit 70 is configured as a microprocessor centering on a CPU, and includes a ROM for storing processing programs, a RAM for temporarily storing data, and an input / output port in addition to the CPU.

  Signals from various sensors are input to the electronic control unit 70 through input ports. As a signal input to the electronic control unit 70, for example, the crank angle θcr from the crank position sensor 23a that detects the rotational position of the crankshaft 23 of the engine 22, and the rotational position that detects the rotational position of the rotor of the motor 30 The rotational position θm of the rotor of the motor 30 from the detection sensor (for example, resolver) 30a can be mentioned. Also, the voltage Vb of the battery 60 from the voltage sensor attached between the terminals of the battery 60 and the current Ib of the battery 60 from the current sensor attached to the output terminal of the battery 60 can be mentioned. Further, the ignition signal from the ignition switch 80, the shift position SP from the shift position sensor 82 for detecting the operation position of the shift lever 81, and the accelerator opening Acc from the accelerator pedal position sensor 84 for detecting the depression amount of the accelerator pedal 83. The brake pedal position BP from the brake pedal position sensor 86 that detects the amount of depression of the brake pedal 85, the vehicle speed V from the vehicle speed sensor 88, and the outside temperature Tatm from the outside temperature sensor 90 that detects the outside temperature .

  Various control signals are outputted from the electronic control unit 70 through the output port. As a signal output from the electronic control unit 70, for example, a control signal to the engine 22 can be mentioned. Further, control signals to the inverter 32, control signals to the clutch 36, and control signals to the transmission 40 can also be mentioned. The electronic control unit 70 calculates the rotational speed Ne of the engine 22 based on the crank angle θcr of the engine 22 from the crank position sensor 23a, or based on the rotational position θm of the rotor of the motor 30 from the rotational position detection sensor 30a. The rotation speed Nm of the motor 30 (the rotation speed Natin of the input shaft 41 of the transmission 40) is calculated.

  In the hybrid vehicle 20 of the embodiment configured as described above, the motor travel (EV travel) mode in which the vehicle travels using power from the motor 30 with the clutch 36 off and the engine 22 and the motor 30 with the clutch 36 on. It travels in the hybrid travel (HV travel) mode where it travels using the power from.

  In the EV drive mode, control is basically performed as follows. First, the target gear position n * of the transmission 40 is set based on the shift line for the accelerator opening Acc and the vehicle speed V, and when the gear position (n) of the transmission 40 is the target gear position (n *) When the shift speed (n) is held and the shift speed (n) of the transmission 40 is not the target shift speed (n *), the shift speed (n) becomes the target shift speed (n) on condition that the shift is permitted. The transmission 40 is controlled to be *). Further, the required torque Tp * of the drive shaft 46 (the output shaft of the transmission 40) is set based on the accelerator opening Acc and the vehicle speed V, and the required torque Tp * of the drive shaft 46 and the gear position of the transmission 40 (n The required torque Tin * of the input shaft 41 of the transmission 40 is calculated based on the gear ratio ((n) of The gear ratio ((n) of the transmission gear position (n) of the transmission 40 can be set in advance. Then, the torque command Tm * of the motor 30 is set so that the required torque Tin * is output to the input shaft 41, and switching control of the plurality of switching elements of the inverter 32 is performed such that the motor 30 is driven by the torque command Tm *. Do. While traveling in the EV travel mode, the storage ratio of the battery 60 (the ratio of the stored capacity to the total capacity of the battery 60) SOC becomes less than a predetermined ratio SOC1 (for example, 15%, 20%, 25%, etc.) When the engine 22 is turned on, the engine 22 is started to shift to traveling in the HV traveling mode. The engine 22 is started by turning on the clutch 36 and motoring the engine 22 with the motor 30 to rotate the engine 22 at a rotational speed Ne (= the rotational speed Nm of the motor 30) to a predetermined rotational speed Nref (for example, 800 rpm, 1000 rpm, 2000 rpm, etc.) ), And when the rotation speed Ne of the engine 22 reaches a predetermined rotation speed Nref, fuel injection control or ignition control of the engine 22 is started.

  In the HV travel mode, control is basically performed as follows. The control of the transmission 40 is controlled in the same manner as in the EV travel mode. The control of the engine 22 and the motor 30 first calculates the required torque Tin * of the input shaft 41 similarly to the EV travel mode, and is based on the rotational speed Ne of the engine 22 (= the rotational speed Nm of the motor 30) and the fuel consumption operation line The target torque Te * of the engine 22 is set, and the torque command Tm * of the motor 30 is set so that the required torque Tin * is output to the input shaft 41. Here, the fuel consumption operation line of the engine 22 is a line that defines the relationship among the power Pe, the rotational speed Ne, and the torque Te of the engine 22 that can operate the engine 22 efficiently. Then, the engine 22 is controlled such that the engine 22 is operated at the target torque Te *, and switching control of a plurality of switching elements of the inverter 32 is performed such that the motor 30 is driven at the torque command Tm *. When the storage ratio SOC of the battery 60 is higher than the predetermined ratio SOC1 during traveling in the HV travel mode, the operation of the engine 22 is stopped when the predetermined ratio SOC2 (eg, 75%, 80%, 85%, etc.) is higher than the predetermined ratio SOC1. Then, the clutch 36 is turned off to shift to the travel in the EV travel mode.

  Next, the operation of the hybrid vehicle 20 of the embodiment configured as described above, in particular, the operation when traveling at a low temperature will be described. FIG. 2 is a flowchart showing an example of an EV travel time processing routine executed by the CPU of the electronic control unit 70. The EV travel time processing routine is repeatedly executed during travel in the EV travel mode. FIG. 3 is a flowchart showing an example of an HV traveling process routine executed by the CPU of the electronic control unit 70. The HV travel time processing routine is repeatedly executed during travel in the HV travel mode. The EV travel time processing routine will be described first, and then the HV travel time processing routine will be described.

  When the EV traveling process routine illustrated in FIG. 2 is executed, the CPU of the electronic control unit 70 executes a process of inputting the outside air temperature Tatm (step S100). As the outside air temperature Tatm, one detected by the outside air temperature sensor 90 is input.

  Subsequently, it is determined whether the input outside temperature Tatm is equal to or less than a predetermined temperature Tref (step S110). The predetermined temperature Tref is the lower limit (e.g., a guaranteed temperature range) of the temperature range that ensures that the operation of various components (e.g., IGBTs as switching elements) that configure the inverter 32 that drives the motor 30 is properly performed. (Eg, -34.degree. C., etc.).

  When the outside air temperature Tatm is higher than the predetermined temperature Tref in step S110, it is determined that the temperature of various parts constituting the inverter 32 for driving the motor 30 is unlikely to fall below the lower limit of the guaranteed temperature range, and the EV traveling processing routine Finish.

  When the outside air temperature Tatm is equal to or less than the predetermined temperature Tref in step S110, it is determined that the temperatures of various parts constituting the inverter 32 may fall below the lower limit of the guaranteed temperature range, and the engine 22 is started (step S120). ), And ends the EV running time processing routine. The start of the engine 22 is described above. By such processing, it is possible to shift from traveling in the EV traveling mode to traveling in the HV traveling mode before the temperatures of various parts constituting the inverter 32 for driving the motor 30 fall below the lower limit of the guaranteed temperature range. Thus, traveling can be continued at a low temperature where the outside air temperature Tatm is lower than or equal to the predetermined temperature Tref.

  Next, an HV traveling process routine exemplified in FIG. 3 will be described. When the HV traveling process routine is executed, the outside air temperature Tatm is input in the same process as step S100 in FIG. 2 (step S200), and the outside air temperature Tatm input in the process similar to step S110 in FIG. It is determined whether the temperature is equal to or less than a predetermined temperature Tref (step S210). When the outside air temperature Tatm is higher than the predetermined temperature Tref, it is determined that there is no problem in shifting to the EV travel mode since the possibility that the temperatures of various parts constituting the inverter 32 fall below the lower limit of the guaranteed temperature range is acceptable. The traveling in the mode is permitted (step S220), and the HV traveling process routine is ended. If traveling in the EV traveling mode is permitted, as described above, if the storage ratio SOC of the battery 60 becomes equal to or higher than the predetermined ratio SOC2 during traveling in the HV traveling mode, transition to traveling in the EV traveling mode is made.

  When the outside air temperature Tatm is equal to or less than the predetermined temperature Tref in step S210, there is a high possibility that the temperatures of various parts constituting the inverter 32 fall below the lower limit of the guaranteed temperature range. It is determined that the vehicle can not be continued, the shift to the EV travel mode is inhibited (step S230), and the HV travel time processing routine is ended. If the shift to the EV travel mode is prohibited, even if the storage ratio SOC of the battery 60 becomes a predetermined ratio SOC2 or more during travel in the HV travel mode, transition to travel in the EV travel mode is not performed in the HV travel mode. Continue running. Thus, traveling can be continued even when the outside temperature Tatm is a low temperature equal to or lower than the predetermined temperature Tref.

  In the hybrid vehicle 20 of the embodiment described above, the engine 22 is started when the outside temperature Tatm is lower than or equal to the predetermined temperature Tref which is 1 ° C. higher than the lower limit of the guaranteed temperature range of the inverter 32 during traveling in the EV traveling mode. By controlling the engine 22 and the inverter 32, traveling can be continued at low temperatures.

  In the hybrid vehicle 20 of the embodiment, the battery 60 is used as the power storage device, but instead of the battery 60, a capacitor may be used.

  Although the hybrid vehicle 20 of the embodiment includes the transmission 40, the transmission 40 may not be provided.

  The embodiment exemplifies the case where the present invention is applied to a hybrid vehicle 20 of the type in which the crankshaft 23 of the engine 22 and the rotational shaft of the motor 30 are connected via the clutch 36. The present invention is applicable to any type of hybrid vehicle including an engine, a motor for motoring the engine, and a drive device for driving the motor, such as a hybrid vehicle of a type in which the motor is connected via a planetary gear. It does not matter.

  In the embodiment, the present invention is described in the form of the hybrid vehicle 20, but it may be in the form of a control method of the hybrid vehicle 20.

  The correspondence between the main elements of the embodiment and the main elements of the invention described in the section of "Means for Solving the Problems" will be described. In the embodiment, the engine 22 corresponds to an "engine", the motor 30 corresponds to a "motor", the inverter 32 corresponds to a "drive device", and the electronic control unit 70 corresponds to a "control device".

  In addition, the correspondence of the main elements of the embodiment and the main elements of the invention described in the section of the means for solving the problem implements the invention described in the column of the means for solving the problem in the example. The present invention is not limited to the elements of the invention described in the section of “Means for Solving the Problems”, as it is an example for specifically explaining the mode for carrying out the invention. That is, the interpretation of the invention described in the section of the means for solving the problem should be made based on the description of the section, and the embodiment is an embodiment of the invention described in the section of the means for solving the problem. It is only a specific example.

  As mentioned above, although the form for implementing this invention was demonstrated using the Example, this invention is not limited at all by these Examples, In the range which does not deviate from the summary of this invention, it becomes various forms Of course it can be implemented.

  The present invention is applicable to the manufacturing industry of hybrid vehicles and the like.

 Reference Signs List 20 hybrid vehicle, 22 engine, 23 crankshaft, 23a crank position sensor, 30 motor, 30a rotational position detection sensor, 32 inverter, 36 clutch, 40 transmission, 41 input shaft, 46 drive shaft, 50a, 50b drive wheel, 56 Axle, 57 differential gear, 60 battery, 61 power line, 70 electronic control unit, 80 ignition switch, 81 shift lever, 82 shift position sensor, 83 accelerator pedal, 84 accelerator pedal position sensor, 85 brake pedal, 86 brake pedal position sensor , 88 Vehicle speed sensor, outside air temperature sensor 90.

Claims (1)

With the engine,
A motor for motoring the engine;
A drive device for driving the motor;
A plurality of travel modes including a hybrid travel mode in which the engine and the motor travel with power from the motor with the operation of the engine, and motor travel in which the operation of the engine is stopped and travels with the power from the motor A control device that controls the engine and the drive device to travel;
A hybrid vehicle comprising
The control device is configured to start the engine and the engine so as to start the engine when the outside air temperature is equal to or lower than a predetermined temperature higher by 1 ° C. than the lower limit temperature of the drive device during the traveling in the motor traveling mode. Control the drive and
Hybrid vehicles.

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