JP6884985B2 - Hybrid vehicle start acceleration control system, hybrid vehicle and hybrid vehicle start acceleration control method - Google Patents

Description

The present invention relates to a start acceleration control system for a hybrid vehicle including an engine and a motor generator which are power sources for vehicle traveling and a control device, and a start acceleration control method for the hybrid vehicle and the hybrid vehicle. More specifically, the present invention relates to a hybrid vehicle start acceleration control system capable of suppressing vibration caused by a suspension or damper system generated during vehicle start acceleration, and a hybrid vehicle and a hybrid vehicle start acceleration control method.

In recent years, from the viewpoint of improving fuel efficiency and environmental measures, a hybrid vehicle (hereinafter referred to as "HEV") equipped with a hybrid system having an engine and a motor generator that are controlled in a complex manner according to the driving state of the vehicle has attracted attention. There is. In this HEV, the driving force is assisted by the motor generator when the vehicle is accelerating or starting, while regenerative power generation is performed by the motor generator during inertial running or starting (see, for example, Patent Document 1).

In this HEV as well, the suspension and damper (shock absorber) provided in the vehicle vibrate according to the behavior of the vehicle when the vehicle starts and accelerates, as in the case of a vehicle in which only the engine is used as the power source for traveling the vehicle. Surge behavior occurs. Since this surge behavior causes discomfort to the driver of the vehicle, conventionally, it is a torque required to increase or decrease the fuel injection amount of the engine to suppress the surge behavior torque. Suppressed surge behavior by generating surge behavior suppression torque that is in opposite phase.

However, if the fuel injection amount of the engine is increased or decreased in order to suppress the surge behavior, the boost pressure of the turbocharger system and the flow rate of EGR gas of the EGR system will also change due to a sudden change in the fuel injection amount. There was a concern that the exhaust gas performance would deteriorate and the fuel efficiency would deteriorate, such as an increase in the amount of NOx and PM in the exhaust gas.

In addition, although it is not controlled when the vehicle starts and accelerates, two motors are used: an internal combustion engine, a first motor for controlling the rotation speed of the internal combustion engine, and a second motor that regenerates the inertial energy of the vehicle to generate power. A hybrid vehicle equipped with vibration control that suppresses spring vibration of the vehicle by at least one of the two motors, and is one of the electric power generated by the second motor due to the inertial energy of the vehicle. In the regenerative state where the unit is supplied to the first motor and the internal combustion engine is forcibly rotated by the first motor, the limit value of the vibration damping torque that suppresses the spring vibration is reduced, and the fluctuation amount of the vibration damping torque A regenerative control device for a hybrid vehicle has been proposed (see, for example, Patent Document 2).

However, in the above-mentioned regenerative control device for a hybrid vehicle, the control is based on the configuration of a hybrid vehicle equipped with an internal combustion engine and two motors, so that the control content becomes complicated and the responsiveness of the control deteriorates. There is.

JP-A-2002-238105 Japanese Unexamined Patent Publication No. 2010-89619

An object of the present invention is a hybrid vehicle start acceleration control system capable of quickly and surely suppressing surge behavior generated in a hybrid vehicle while preventing deterioration of exhaust gas performance and fuel efficiency when the hybrid vehicle starts and accelerates. , A hybrid vehicle and a method for controlling the start acceleration of the hybrid vehicle.

The hybrid vehicle start acceleration control system of the present invention that achieves the above object is a hybrid vehicle start acceleration control system including a hybrid system having an engine and a motor generator, which are power sources for vehicle traveling, and a control device. In the control system, the control device outputs a basic torque from the motor generator when the hybrid vehicle starts and accelerates, and is based on the vehicle speed, the engine speed, the gear stage of the transmission connected to the engine, and the accelerator opening. It is generated in the hybrid vehicle when the increase / decrease value of the fuel injection amount of the engine is estimated and calculated, and when the charge amount of the battery connected to the motor generator via the inverter is equal to or more than a preset set threshold value. This estimation is calculated by estimating and calculating the surge behavior suppression torque, which is the torque opposite to the surge behavior torque and is the torque for suppressing the surge behavior torque, based on the estimated increase / decrease value of the fuel injection amount. When the surge behavior suppression torque is generated by switching between the assist of the motor generator and the power generation, the basic torque is controlled to increase or decrease by the surge behavior suppression torque, and the charge amount of the battery is less than the set threshold value. Is configured to control to generate the surge behavior suppression torque by increasing or decreasing the fuel injection amount of the engine by the increase / decrease value of the estimated calculated fuel injection amount.

Here, the surge behavior torque is the torque (unit: Nm) generated by the surge behavior, which is a phenomenon in which the suspension and damper (shock absorber) provided in the vehicle vibrate with the behavior of the vehicle when the vehicle starts and accelerates. Is.

Further, the time of starting and accelerating the vehicle is the time of starting and accelerating the vehicle. More specifically, when the vehicle starts, it is when the vehicle speed starts to increase, and when the vehicle accelerates, it is when the vehicle speed increases.

Further, the hybrid vehicle of the present invention that achieves the above object is configured to include the above-mentioned hybrid vehicle start acceleration control system , suspension and damper .

Further, the method for controlling the start acceleration of a hybrid vehicle of the present invention, which achieves the above object, is a method for controlling the start acceleration of a hybrid vehicle provided with a hybrid system having an engine and a motor generator as a power source for vehicle traveling. When the hybrid vehicle starts and accelerates, the basic torque is output from the motor generator , and the increase / decrease value of the fuel injection amount of the engine is based on the vehicle speed, the engine speed, the gear stage of the transmission connected to the engine, and the accelerator opening. Is estimated and calculated, and when the charge amount of the battery connected to the motor generator via the inverter is equal to or more than a preset set threshold value, the torque is opposite to the surge behavior torque generated in the hybrid vehicle. Then, the surge behavior suppression torque, which is the torque for suppressing the surge behavior torque, is estimated and calculated based on the estimated increase / decrease value of the fuel injection amount, and the estimated calculated surge behavior suppression torque is calculated by the motor generator. It is generated by switching between assist and power generation, and control is performed to increase or decrease the basic torque by the surge behavior suppression torque. When the charge amount of the battery is less than the set threshold value, the estimated calculated fuel injection is performed. This method is characterized in that the surge behavior suppression torque is generated by increasing or decreasing the fuel injection amount of the engine by the increase or decrease value of the amount.

According to the start acceleration control system of the hybrid vehicle and the start acceleration control method of the hybrid vehicle and the hybrid vehicle of the present invention, the surge behavior suppression for suppressing the surge behavior torque generated in the hybrid vehicle during the start acceleration of the hybrid vehicle is suppressed. The torque is generated by increasing or decreasing the torque of the motor generator (switching between assist and power generation) instead of increasing or decreasing the fuel injection amount of the engine and generating it by the output torque of the engine as in the conventional technology. It is possible to prevent the deterioration of the exhaust gas performance and the fuel consumption performance without causing problems such as deterioration of the exhaust gas performance and deterioration of the fuel consumption due to the increase / decrease of the fuel injection amount.

Further, since the surge behavior torque is suppressed by increasing or decreasing the torque of the motor generator, the responsiveness of the control is good, and the surge behavior generated in the hybrid vehicle can be quickly suppressed.

In addition, the surge behavior torque generated in the hybrid vehicle when the hybrid vehicle starts and accelerates is either increased or decreased in the fuel injection amount of the engine or the torque of the motor generator is increased or decreased based on the charge amount of the battery for the motor generator. If it is performed by one side, the surge behavior generated in the hybrid vehicle can be surely suppressed.

It is a block diagram of the hybrid vehicle provided with the start acceleration control system of the hybrid vehicle which concerns on embodiment of this invention. It is a figure which shows the control flow of the control method at the time of start acceleration of the hybrid vehicle which concerns on embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a hybrid vehicle provided with a start acceleration control system for the hybrid vehicle according to the embodiment of the present invention.

This hybrid vehicle (hereinafter referred to as "HEV") is a vehicle that includes not only ordinary passenger cars but also buses and trucks, and has an engine 10 and a motor generator 31 that are complexly controlled according to the operating state of the vehicle. It is equipped with a hybrid system 30.

In the engine 10, the crankshaft 13 is rotationally driven by heat energy generated by combustion of fuel in a plurality of (four in this example) cylinders 12 formed in the engine body 11. A diesel engine or a gasoline engine is used for the engine 10. The rotational power of the crankshaft 13 is transmitted to the transmission 20 through a clutch 14 (for example, a wet multi-plate clutch) connected to one end of the crankshaft 13.

The rotational power shifted by the transmission 20 is transmitted as driving force to each pair of driving wheels (not shown).

The hybrid system 30 includes a motor generator 31, an inverter 35 that is electrically connected to the motor generator 31 in this order, a high-voltage battery 32, a DC / DC converter 33, and a low-voltage battery 34.

As the high voltage battery 32, a lithium ion battery, a nickel hydrogen battery, and the like are preferably exemplified. A lead battery is used as the low voltage battery 34.

The motor generator 31 is endlessly hung between the first pulley 15 attached to the rotating shaft 37 and the second pulley 16 attached to the other end of the crankshaft 13 which is the output shaft of the engine body 11. Power is transmitted to and from the engine 10 via the belt-shaped member 17. It is also possible to transmit power by using a gearbox or the like instead of the two pulleys 15 and 16 and the belt-shaped member 17. Further, the output shaft of the engine body 11 connected to the motor generator 31 is not limited to the crankshaft 13, and may be, for example, a transmission shaft between the engine body 11 and the transmission 20.

The motor generator 31 has a function of performing cranking.

The engine 10 and the hybrid system 30 are controlled by the control device 80. Specifically, when the HEV is started or accelerated, the hybrid system 30 assists at least a part of the driving force by the motor generator 31 supplied with power from the high voltage battery 32, while during inertial running or deceleration. Performs regenerative power generation by the motor generator 31 and converts excess kinetic energy into electric power to charge the high-voltage battery 32.

The start acceleration control system for a hybrid vehicle of the present invention is a system including a hybrid system 30 including an engine 10 and a motor generator 31 which are power sources for traveling the vehicle, and a control device 80.

Then, the control device 80 sets the surge behavior suppression torque ΔT, which is the torque for suppressing the surge behavior torque, which is the torque opposite to the surge behavior torque generated in the hybrid vehicle when the hybrid vehicle starts and accelerates. It is estimated and calculated based on the engine speed, the gear stage of the transmission 20 connected to the engine 10, and the accelerator opening.

More specifically, a control type or a control type in which an increase / decrease value of the fuel injection amount of the engine 10 for suppressing surge behavior is set based on four parameters of vehicle speed, engine speed, transmission gear stage, and accelerator opening. A control map is created in advance by an experiment or the like and stored in the control device 80. This control formula or control map is similarly created even when the surge behavior is suppressed by the output torque of the engine of the prior art. Then, when the hybrid vehicle starts and accelerates, the increase / decrease value ΔF of the fuel injection amount of the engine 10 is estimated and calculated from the above control formula or control map stored in the control device 80 based on the detection values of the above four parameters. .. In the prior art, the surge behavior of the hybrid vehicle is suppressed by increasing or decreasing the fuel injection amount of the engine 10 by the estimated increase / decrease value ΔF of the fuel injection amount of the engine 10.

On the other hand, in the present invention, the surge behavior suppression torque ΔT, which is the torque to be generated by the motor generator 31 in order to suppress the surge behavior, is estimated and calculated based on the estimated calculation of the increase / decrease value ΔF of the fuel injection amount of the engine 10. To do. Then, the motor generator 31 controls to generate the estimated and calculated surge behavior suppression torque ΔT. This control is performed for about 2 to 3 seconds. More specifically, the surge behavior torque and the surge behavior suppression torque ΔT are opposite to the basic torque T set as the start acceleration torque generated by the motor generator 31 when the hybrid vehicle starts and accelerates. , The torque of this surge behavior suppression torque ΔT is increased or decreased (T + ΔT or T−ΔT).

The surge behavior torque refers to the suspension (not shown) and damper (shock absorber) (not shown) provided in the vehicle when the vehicle starts and accelerates. It is a phenomenon that vibrates until the state of the elastic body stabilizes after shifting to the running state. The torque generated by the vibration generated during this transition period is the surge behavior torque (unit: Nm).

Further, the time of starting and accelerating the vehicle is the time of starting and accelerating the vehicle. More specifically, when the vehicle starts, it is when the vehicle speed starts to increase, and when the vehicle accelerates, it is when the vehicle speed increases.

The vehicle speed is detected by a vehicle speed sensor (not shown) provided on the hybrid vehicle. The engine speed is detected by an engine speed sensor (not shown) provided on the engine 10. The gear stage of the transmission 20 is determined by a transmission controller (not shown), and a gear stage received by the control device 80 by communication is used. The accelerator opening is detected by an accelerator opening sensor (not shown) provided in the driver's seat of the hybrid vehicle.

Regarding the estimation calculation of the surge behavior suppression torque ΔT, for example, a control formula or a control map in which the surge behavior suppression torque ΔT is set based on four parameters of vehicle speed, engine speed, transmission gear stage, and accelerator opening. Is created in advance by an experiment or the like and stored in the control device 80. Then, when the hybrid vehicle starts and accelerates, the surge behavior suppression torque ΔT is estimated and calculated from the control formula or control map stored in the control device 80 based on the detected values of the above four parameters.

Further, in the above-mentioned control system for accelerating the start of the hybrid vehicle, the charge amount S of the high-voltage battery 32 connected to the motor generator 31 via the inverter 35 when the control device 80 accelerates the start of the hybrid vehicle is determined by experiments or the like. When the preset threshold value S1 or more is set, the motor generator 31 controls to generate the estimated and calculated surge behavior suppression torque ΔT (control to increase or decrease the torque of the motor generator 31 by the surge behavior suppression torque ΔT). When the charge amount S of the high-voltage battery 32 is less than the set threshold value S1, the control to generate the estimated calculated surge behavior suppression torque ΔT by the engine 10 (increase / decrease the fuel injection amount of the engine 10 by the increase / decrease value ΔF). It may be configured to perform control).

Next, the start acceleration control method of the hybrid vehicle of the present invention based on the start acceleration control system of the hybrid vehicle will be described with reference to the control flow of FIG. The control flow of FIG. 2 is shown as a control flow that is called and implemented from the higher-level control flow when the vehicle starts and accelerates, and then returns to the higher-level control flow after the execution.

The control flow of FIG. 2 will be described. When the control flow of FIG. 2 starts, in step S10, fuel injection of the engine 10 for suppressing surge behavior is performed based on four parameters of vehicle speed, engine speed, gear stage of transmission 20, and accelerator opening. Estimate and calculate the increase / decrease value ΔF of the amount. After performing the control in step S10, the process proceeds to step S20.

In step S20, it is calculated whether or not the charge amount S of the high-voltage battery 32 is equal to or greater than the preset threshold value S1. When the charge amount S is equal to or higher than the set threshold value S1 (YES), the process proceeds to step S30, and in step S30, the surge behavior suppression torque is based on the increase / decrease value ΔF of the fuel injection amount of the engine 10 estimated and calculated in step S10. Estimate and calculate ΔT. Then, after performing the control in step S30, the process proceeds to step S40, and in step S40, the surge behavior suppression torque ΔT estimated and calculated in step S30 is controlled by the motor generator 31 to suppress the surge behavior of the hybrid vehicle. To do. After performing the control in step S40, the process proceeds to return, the present control flow is terminated, and the process returns to the advanced control flow.

On the other hand, if the charge amount S of the high-voltage battery 32 is less than the set threshold value S1 in step S20 (NO), the process proceeds to step S50, and in step S50, the fuel injection amount of the engine 10 estimated and calculated in step S10. The surge behavior of the hybrid vehicle is suppressed by controlling the increase / decrease of the fuel injection amount of the engine 10 by the increase / decrease value ΔF of. After performing the control in step S50, the process proceeds to return, the present control flow is terminated, and the process returns to the advanced control flow.

As described above, the method for controlling the start acceleration of the hybrid vehicle of the present invention based on the above-mentioned control system for start acceleration of the hybrid vehicle is a hybrid having an engine 10 and a motor generator 31 as a power source for running the vehicle. In the start acceleration control method of a hybrid vehicle equipped with the system 30, the surge has a torque opposite to the surge behavior torque generated in the hybrid vehicle when the hybrid vehicle starts and accelerates, and is a torque for suppressing the surge behavior torque. The behavior suppression torque ΔT is estimated and calculated based on the vehicle speed, the engine speed, the gear stage of the transmission 20 connected to the engine 10, and the accelerator opening, and the estimated surge behavior suppression torque ΔT is generated by the motor generator 31. It is a method characterized by performing control to make the torque.

Further, in the above-mentioned control method for starting acceleration of a hybrid vehicle, the charge amount S of the battery 32 connected to the motor generator 31 via the inverter 35 at the time of starting acceleration of the hybrid vehicle is equal to or higher than a preset setting threshold value S1. In this case, the motor generator 31 controls to generate the estimated and calculated surge behavior suppression torque ΔT, and when the charge amount S of the battery 32 is less than the set threshold value S1, the estimated and calculated surge behavior suppression torque ΔT is performed. Is a method characterized by performing control to generate the above.

According to the start acceleration control system of the hybrid vehicle and the start acceleration control method of the hybrid vehicle and the hybrid vehicle of the present invention, surge behavior suppression for suppressing the surge behavior torque generated in the hybrid vehicle during the start acceleration of the hybrid vehicle is suppressed. The torque ΔT is not generated by increasing or decreasing the fuel injection amount of the engine 10, but is generated by increasing or decreasing the torque of the motor generator 31 (switching between assist and power generation). It is possible to prevent the deterioration of the exhaust gas performance and the fuel consumption performance without causing problems such as deterioration of the exhaust gas performance and deterioration of the fuel consumption due to the increase / decrease.

Further, since the surge behavior torque is suppressed by increasing or decreasing the torque of the motor generator 31, the responsiveness of the control is good, and the surge behavior generated in the hybrid vehicle can be quickly suppressed.

Further, the surge behavior torque generated in the hybrid vehicle when the hybrid vehicle starts and accelerates is increased or decreased by the fuel injection amount of the engine 10 or the torque of the motor generator 31 based on the charge amount S of the battery 32 for the motor generator 31. If it is performed by either increasing or decreasing, the surge behavior generated in the hybrid vehicle can be reliably suppressed regardless of the charge amount S of the battery 32.

10 Engine 11 Engine body 30 Hybrid system 31 Motor generator 32 High voltage battery (battery)
35 Inverter 80 Controller ΔT Surge behavior suppression torque S Battery charge S1 Battery charge setting threshold

Claims (4)

In a start acceleration control system of a hybrid vehicle including a hybrid system having an engine and a motor generator which are power sources for vehicle running and a control device.
The control device
When the hybrid vehicle starts and accelerates, the motor generator outputs a basic torque , and the increase / decrease value of the fuel injection amount of the engine is based on the vehicle speed, the engine speed, the gear stage of the transmission connected to the engine, and the accelerator opening. Is estimated and calculated, and
When the charge amount of the battery connected to the motor generator via the inverter is equal to or higher than a preset threshold value, the surge behavior torque is a torque opposite to the surge behavior torque generated in the hybrid vehicle. The surge behavior suppression torque, which is the torque for suppressing the above, is estimated and calculated based on the estimated increase / decrease value of the fuel injection amount, and the estimated calculated surge behavior suppression torque is switched between the assist of the motor generator and the power generation. By doing so, control is performed to increase or decrease the basic torque by the amount of the surge behavior suppression torque.
When the charge amount of the battery is less than the set threshold value, the surge behavior suppression torque is controlled by increasing or decreasing the fuel injection amount of the engine by the increase / decrease value of the estimated calculated fuel injection amount. A control system for starting acceleration of a hybrid vehicle configured in this way. The hybrid vehicle provided with the start acceleration control system, suspension and damper of the hybrid vehicle according to claim 1. The hybrid vehicle according to claim 2 , wherein the surge behavior torque is a torque generated by vibration of the suspension and the damper accompanying the behavior of the hybrid vehicle. In the start acceleration control method of a hybrid vehicle equipped with a hybrid system having an engine and a motor generator which are power sources for vehicle running.
When the hybrid vehicle starts and accelerates, the motor generator outputs a basic torque , and the increase / decrease value of the fuel injection amount of the engine is based on the vehicle speed, the engine speed, the gear stage of the transmission connected to the engine, and the accelerator opening. Is estimated and calculated, and
When the charge amount of the battery connected to the motor generator via the inverter is equal to or higher than a preset threshold value, the surge behavior torque is a torque opposite to the surge behavior torque generated in the hybrid vehicle. The surge behavior suppression torque, which is the torque for suppressing the above, is estimated and calculated based on the estimated increase / decrease value of the fuel injection amount, and the estimated calculated surge behavior suppression torque is switched between the assist of the motor generator and the power generation. By doing so, control is performed to increase or decrease the basic torque by the amount of the surge behavior suppression torque.
When the charge amount of the battery is less than the set threshold value, the surge behavior suppression torque is controlled by increasing or decreasing the fuel injection amount of the engine by the increase / decrease value of the estimated calculated fuel injection amount. A control method for starting and accelerating a hybrid vehicle.

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