KR20230127405A - Hybrid vehicle and method of controlling charging amount - Google Patents

Abstract

An engine torque control method of a hybrid vehicle according to an embodiment of the present invention includes determining whether to enter a sports mode; comparing a current state of charge (SOC) of a battery with a set reference SOC, if it is determined that the sport mode is determined as a result of the determination; generating a first SOC (ΔSOC) based on a target SOC that is a state of charge (SOC) of a target battery and the current SOC when the current SOC is greater than the reference SOC; determining a compensation factor value based on the generated first SOC (ΔSOC); generating a compensation engine target torque by applying the determined compensation factor value to a reference engine target torque; and setting a limit value in consideration of engine torque change based on the generated compensation engine target torque.

Description

Hybrid vehicle and engine torque control method therefor {HYBRID VEHICLE AND METHOD OF CONTROLLING CHARGING AMOUNT}

The present invention relates to a hybrid vehicle capable of controlling a variation of an engine target torque while compensating in consideration of an engine target torque when determining an engine target torque so as to maintain an appropriate SOC control range in a sport mode driving situation, and an engine torque control method therefor.

As interest in the environment has recently increased, many developments have been made for hybrid electric vehicles (HEVs) and electric vehicles (EVs) using electric motors as a driving source.

A hybrid electric vehicle (HEV) generally refers to a car that uses two power sources together, and the two power sources are mainly an engine and an electric motor. Such a hybrid vehicle has been recently developed because it has excellent fuel efficiency and power performance compared to a vehicle equipped with only an internal combustion engine and is advantageous in reducing exhaust gas. In particular, a hybrid vehicle capable of charging a battery through a plug with external power rather than engine power or regenerative braking is referred to as a plug-in hybrid vehicle (PHEV). In the case of an electric vehicle (EV), unlike a hybrid vehicle, since it cannot generate power on its own except for regenerative braking, charging using external power is essential.

Among the driver selection modes of the above-mentioned hybrid vehicle, the sports mode is a mode that prioritizes power performance. There are characteristics you want to keep.

While driving in this sport mode, the target torque of the engine is output at the OOL level in consideration of efficiency, so the battery is charged as much as the surplus torque during low-load driving, and the SOC continues to rise.

However, if the proper level of SOC is not controlled, the capacity of the high-voltage battery is limited, so the charging limit situation is eventually reached. In that case, since there is almost no discharge through entering the EV mode, the role of the motor is reduced, and the engine outputs only as much torque as the driver's required torque, losing the hybrid function, and the vehicle behaves like a conventional ICE vehicle. do.

The present invention is to provide a hybrid vehicle capable of controlling a variation of an engine target torque while compensating in consideration of the SOC when determining an engine target torque so as to maintain an appropriate SOC control range in a sport mode driving situation, and an engine torque control method therefor. will be.

The technical problems to be achieved in the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art from the description below. You will be able to.

In order to solve the above technical problem, a method for controlling engine torque of a hybrid vehicle according to an embodiment of the present invention includes determining whether to enter a sports mode; comparing a current state of charge (SOC) of a battery with a set reference SOC, if it is determined that the sport mode is determined as a result of the determination; generating a first SOC (ΔSOC) based on a target SOC that is a state of charge (SOC) of a target battery and the current SOC when the current SOC is greater than the reference SOC; determining a compensation factor value based on the generated first SOC (ΔSOC); generating a compensation engine target torque by applying the determined compensation factor value to a reference engine target torque; and setting a limit value considering a change in engine torque based on the generated compensation engine target torque.

In addition, a hybrid vehicle according to an embodiment of the present invention includes a controller, and the controller includes: a mode determining unit that determines whether to enter a sports mode; As a result of the determination, if it is the sports mode, the current SOC, which is the current state of charge (SOC) of the battery, is compared with a set reference SOC, and if the current SOC is greater than the reference SOC, the target battery's state of charge (SOC) ), a generator for generating a first SOC (ΔSOC) based on the target SOC and the current SOC; A compensation factor value is determined based on the generated first SOC (ΔSOC), a compensation engine target torque is generated by applying the determined compensation factor value to a reference engine target torque, and based on the generated compensation engine target torque and a setting unit for setting a limit value considering engine torque change.

The present invention configured as described above not only can compensate by considering the SOC when determining the target engine torque so that an appropriate SOC control range can be maintained in a sport mode driving situation, but also controls the variation of the target engine torque to improve exhaust and fuel efficiency. There is an effect that can be improved.

The present invention compensates the engine target torque according to the SOC in order to maintain an appropriate SOC range during sports mode driving and minimizes sudden engine torque fluctuations, thereby stabilizing exhaust performance and preventing deterioration of the regenerative braking energy recovery rate due to battery charging limit situations. There is an effect.

The effects obtainable in the present invention are not limited to the effects mentioned above, and other effects not mentioned can be clearly understood by those skilled in the art from the description below. will be.

1 shows an example of a configuration of a hybrid vehicle that can be applied to embodiments of the present invention.
2 is a block diagram showing an example of a control system of a hybrid vehicle that can be applied to embodiments of the present invention.
3 shows an example of a structure of a controller for controlling an optimum engine torque according to an embodiment of the present invention.
4 is a flowchart illustrating a method for controlling engine torque of a hybrid vehicle according to an embodiment of the present invention.
5 is a flowchart illustrating a method for controlling engine torque of a hybrid vehicle according to another embodiment of the present invention.
6 is a diagram illustrating a torque variation range for a set period according to an embodiment of the present invention.
7 shows engine torque and driver's requested torque when the battery is charged to the critical high level in SOC.
8 shows the variation of the ignition angle according to the variation of the engine torque.
FIG. 9 is an enlarged view illustrating a change in ignition angle of FIG. 8 .
10 is a diagram illustrating an engine control stability securing region.

Hereinafter, with reference to the accompanying drawings, embodiments of the present invention will be described in detail so that those skilled in the art can easily carry out the present invention. However, the present invention may be implemented in many different forms and is not limited to the embodiments described herein. And in order to clearly explain the present invention in the drawings, parts irrelevant to the description are omitted, and similar reference numerals are attached to similar parts throughout the specification.

Throughout the specification, when a certain component is said to "include", it means that it may further include other components without excluding other components unless otherwise stated. Also, parts denoted with the same reference numerals throughout the specification mean the same components.

In addition, a unit or control unit included in the name of a hybrid controller (HCU: Hybrid Control Unit) is just a term widely used for naming a controller that controls vehicle-specific functions, It does not mean a generic function unit. For example, each controller is a communication device that communicates with other controllers or sensors to control the function in charge, a memory that stores operating system or logic commands and input/output information, and a controller that performs judgment, calculation, and decision necessary for controlling the function in charge. It may include more than one processor.

Prior to describing an engine torque control method according to an embodiment of the present invention, a structure and a control system of a hybrid vehicle applicable to the embodiments will be first described with reference to FIGS. 1 and 2 . It is apparent to those skilled in the art that the vehicle structure described below with reference to FIGS. 1 and 2 can be similarly applied to an electric vehicle (EV), except for parts related to an internal combustion engine.

1 shows an example of a configuration of a hybrid vehicle that can be applied to embodiments of the present invention.

Referring to FIG. 1 , a hybrid vehicle according to an embodiment includes an electric motor (or driving motor, 140) and an engine clutch (EC: Engine Clutch, 130) between an internal combustion engine (ICE, 110) and a transmission 150. A parallel type (Parallel Type or TMED: Transmission Mounted Electric Drive) hybrid powertrain equipped with may be provided.

In such a vehicle, generally, when a driver steps on an accelerator after starting, the motor 140 (or driving motor) is first driven by using power from a battery (not shown) while the engine clutch 130 is open, and the motor 140 ) The power of the transmission 150 and the final reducer (FD: Final Drive, 160) moves the wheels (ie, EV mode). When the vehicle is gradually accelerated and gradually greater driving force is required, the start-up motor 120 may operate to drive the engine 110 .

Accordingly, when the rotation speed of the engine 110 and the motor 140 are substantially the same, the engine clutch 130 is engaged so that the engine 110 and the motor 140 together or the engine 110 drives the vehicle. (i.e. transition from EV mode to HEV mode). When a preset engine-off condition, such as a vehicle deceleration, is satisfied, the engine clutch 130 is opened and the engine 110 is stopped (ie, a transition from the HEV mode to the EV mode). In addition, in a hybrid vehicle, driving force of a wheel is converted into electric energy during braking to charge a battery (not shown), which is referred to as braking energy regeneration or regenerative braking.

The starting generator motor 120 serves as a starter motor when the engine 110 is started, and operates as a generator when the rotational energy of the engine 110 is recovered after the engine is started or when the engine 110 is turned off. Generator (HSG: Hybrid Starter Generator)", and in some cases, it may be referred to as "auxiliary motor".

2 is a block diagram showing an example of a control system of a hybrid vehicle that can be applied to embodiments of the present invention. The control system shown in FIG. 2 may be applied to a vehicle to which the power train described above with reference to FIG. 1 is applied.

Referring to FIG. 2 , in a hybrid vehicle to which embodiments of the present invention can be applied, an internal combustion engine 110 is controlled by an engine controller 210, and an engine controller 210 and a starter motor 120 and a drive motor 140 are controlled by a motor controller (MCU). : Torque can be controlled by the motor control unit 220, and the engine clutch 130 can be controlled by the clutch controller 230, respectively. Here, the engine controller 210 may also be referred to as an engine management system (EMS). In addition, the transmission controller 250 controls the transmission 150. In some cases, a controller for the start-up motor 120 and a controller for each of the drive motors 140 may be provided separately.

Each controller, as its upper controller, is connected to a hybrid controller (HCU: Hybrid Controller Unit, 240) that controls the entire mode conversion process, and changes the driving mode under the control of the hybrid controller 240 and controls the engine clutch during gear shifting. Information and/or information required for engine stop control may be provided to the hybrid controller 240 or an operation may be performed according to a control signal.

For example, the hybrid controller 240 may perform overall power train control in vehicle operation. For example, the hybrid controller 240 may determine an open time of the engine clutch 130 . In addition, the hybrid controller 240 may determine the state (Lock-up, Slip, Open, etc.) of the engine clutch 130 and control the fuel injection stop timing of the engine 110 . In addition, the hybrid controller 240 may control the recovery of engine rotational energy by transmitting a torque command for controlling the torque of the start-up motor 120 to the motor controller 220 for engine stop control.

In addition, the hybrid controller 240 determines whether to enter the sports mode, and as a result of the determination, if it is the sports mode, compares the current state of charge (SOC) of the battery with a set reference SOC, When the current SOC is greater than the reference SOC, a target SOC that is a state of charge (SOC) of a target battery and a first SOC (ΔSOC) are generated based on the current SOC, and based on the generated first SOC (ΔSOC) A compensation factor value is determined, a compensation engine target torque is generated by applying the determined compensation factor value to a reference engine target torque, and whether the generated first SOC (ΔSOC) is included in a preset reference range (Cal.A). control to set a target engine torque limit value by determining whether or not, setting a torque variation range differently according to the determination result, and applying the torque variation range set to the compensating engine target torque.

Of course, it is obvious to those skilled in the art that the above-described connection relationship between controllers and functions/divisions of each controller are exemplary and are not limited to their names. For example, the hybrid controller 240 may be implemented such that a corresponding function is replaced and provided in any one of the other controllers other than the hybrid controller 240, or a corresponding function may be distributed and provided in two or more of the other controllers.

Hereinafter, based on the above-described vehicle structure, a more efficient engine torque control method according to an embodiment of the present invention and a vehicle structure therefor will be described.

3 shows an example of a structure of a controller for controlling an optimum engine torque according to an embodiment of the present invention.

In the drawings and descriptions below including FIG. 3 , it is assumed that the controller controlling the engine torque is the hybrid controller 240 . However, this is illustrative and is not necessarily limited thereto.

The controller structure shown in FIG. 3 can be applied to an EV mode or a charge depleting (CD) mode of a hybrid vehicle or an electric vehicle. Referring to FIG. 3 , the hybrid controller 240 may include a mode determination unit 241 , a generation unit 242 , a setting unit 243 and a determination unit 244 .

The mode determining unit 241 may determine whether to enter a sports mode. When a drive mode is selected by a driver or a user, the mode determining unit 241 may detect the selected mode and determine a mode for this. The drive mode may include a normal mode, an eco mode, or a sport mode.

The mode determination unit 241 may determine a normal mode, an eco mode, or a sports mode in the drive mode in consideration of a relationship such as torque, RPM, and gear shift of the vehicle. The eco mode may be a mode for driving at a lower RPM by shifting gears faster than the normal mode, and the sport mode may be a mode driving at a higher RPM by shifting slower than the normal mode.

As a result of the determination, if the driving mode is a sports mode, the generator 242 may compare the current state of charge (SOC) of the battery with a set reference SOC. The reference SOC of the battery may be divided into a plurality of stages according to the range of the SOC, such as critical high, high, normal, low, and critical low.

For example, the hybrid controller 240 may control charging of the battery to be limited when the SOC is charged up to the critical high level in a situation where the SOC charge/discharge control is not possible during driving in the sports mode. At this time, since the output torque of the engine is determined according to the driver's requested torque, smooth torque leveling is not possible and the torque fluctuation between the engine torque and the driver's requested torque increases. To prevent this, the generating unit 242 may set a reference SOC corresponding to the sports mode when driving in the sports mode under the control of the hybrid controller 240 .

Under the control of the hybrid controller 240, the generation unit 242 considers the vehicle state information, distance information to the destination, weather information, temperature information, mode information determined by the mode determination unit 241, and the like, and the reference SOC can be set. For example, the generator 242 may set the reference SOC to High in the case of the eco mode, set the reference SOC to Normal in the case of the normal mode, and set it to Low in the case of the sports mode. This is only an example, and is not necessarily limited thereto.

When the current SOC is greater than the reference SOC as a result of comparison, the generation unit 242 may generate the first SOC (ΔSOC) based on the target SOC of the battery and the current SOC. That is, when it is determined that the current SOC is greater than the set reference SOC, the generation unit 242 may generate the first SOC (ΔSOC) by removing as much as the current SOC from the target SOC of the battery. For example, the first SOC (ΔSOC) may be a difference value between a target SOC of the battery and a current SOC.

The setting unit 243 determines a compensation factor value based on the generated first SOC (ΔSOC), generates a compensation engine target torque by applying the determined compensation factor value to a reference engine target torque, and generates a compensation engine target torque. It is possible to set a limit value considering the change in engine torque based on .

In addition, the setting unit 243 determines a compensation factor value based on the generated first SOC (ΔSOC), generates a compensation engine target torque by applying the determined compensation factor value to a reference engine target torque, and generates a first compensation engine target torque. It may be determined whether SOC (ΔSOC) is included in a predetermined reference range (Cal.A). In this case, the first SOC (ΔSOC) may be an absolute value of ΔSOC.

The setting unit 243 sets the generated first SOC (ΔSOC) as the first period (α) when it is within the preset reference range (Cal.A), and sets the generated first SOC (ΔSOC) to the preset reference range. If it is out of the range (Cal.A), it can be set as a second period (β) different from the first period (α). In this case, the second period β may have a wider range than the first period α.

The setting unit 243 sets the torque variation range differently according to the determination result, but sets the engine target torque limit value by applying the torque variation range set to the compensation engine target torque.

As a result of the determination, when the generated first SOC (ΔSOC) includes the preset reference range (Cal.A), the setting unit 243 sets the torque variation range for the set first period (α) as a first calibration factor ( CAL1) and the third calibration factor CAL3. That is, the torque variation range for the first period (α) may limit the rate of rise or fall per unit time based on the first calibration factor (CAL1) and the third calibration factor (CAL3), but this is only an example, Not limited to this.

Accordingly, when the first SOC (ΔSOC) generated under the control of the hybrid controller 240 satisfies the preset reference range (Cal.A), the setting unit 243 controls the engine torque fluctuation within the control stability securing region. can

In addition, as a result of the determination, when the generated first SOC (ΔSOC) is out of the preset reference range (Cal.A), the setting unit 243 sets the torque variation range for the second period (β) as a second calibration factor. It can be set based on (CAL2) and the fourth calibration factor (CAL4). That is, the torque variation range for the second period β may limit the rate of rise or fall per unit time based on the second calibration factor CAL2 and the fourth calibration factor CAL4, but this is only an example, Not limited to this.

The above-described first calibration factor CAL1 to fourth calibration factor CAL4 are data about the driving state of the vehicle, engine torque of the vehicle, ignition angle, compensation engine target torque, torque variation range, etc. under the control of the hybrid controller 240 It may be learned based on at least one of the above, and may be set in consideration of the learned result value. It is not limited thereto, and may be set through a compensation factor map or table according to the generated first SOC (ΔSOC).

Also, the first calibration factor CAL1 may have a smaller or lower factor value than the second calibration factor CAL2 . The third calibration factor CAL3 may have a smaller or lower factor value than the fourth calibration factor CAL4 . That is, the range of variation between the first calibration factor CAL1 and the third calibration factor CAL3 may be smaller than the range of variation between the second calibration factor CAL2 and the fourth calibration factor CAL4 .

The setting unit 243 may receive and compare the generated first SOC (ΔSOC), and set an upper limit torque and a lower limit torque based on the result of the comparison and analysis.

In addition, the setting unit 243 compares and analyzes the first calibration factor CAL1, the second calibration factor CAL2, the third calibration factor CAL3, and the fourth calibration factor CAL4, and compares and analyzes the result Based on the value, upper limit torque and lower limit torque can be set. For example, each of the set upper limit torque and lower limit torque may be applied to the first period (α) or the second period (β).

The setting unit 243 may set the partial load as the maximum torque when the criterion for the upper limit torque is set as a partial load smaller than the standard load of the reference engine. That is, the setting unit 243 may set the partial load as the maximum torque in consideration of the brake specific fuel consumption (BSFC) of the reference engine as the lower limit torque in order to minimize the reduction in efficiency.

The determiner 244 may determine an engine output torque command based on at least one of a set limit value, an upper limit torque, a lower limit torque, and a compensated engine target torque.

4 is a flowchart illustrating a method for controlling engine torque of a hybrid vehicle according to an embodiment of the present invention.

Referring to FIG. 4 , a method for controlling engine torque of a hybrid vehicle according to an embodiment of the present invention is as follows.

First, it is a step of determining whether to enter a sports mode (S111). According to the present invention, when a sport mode is selected among drive modes, it is possible to enter the sport mode. The present invention may end when an eco mode or a normal mode, not a sports mode, is selected among the drive modes (No in S111).

As a result of the determination, if it is a sports mode, this is a step of comparing the current SOC, which is the state of charge (SOC) of the battery, with a set reference SOC (S112). The reference SOC of the battery may be divided into a plurality of stages according to the range of the SOC, such as critical high, high, normal, low, and critical low. The hybrid controller 240 controls the generation unit 242 to take into consideration the vehicle state information, distance information to the destination, weather information, temperature information, and the mode information determined by the mode determination unit 241 to consider the reference SOC. can be set.

If it is determined that the current SOC is smaller than the set reference SOC, the hybrid controller 240 may continuously compare the current SOC with the set reference SOC (No in S112).

Thereafter, when the current SOC is greater than the reference SOC, generating a first SOC (ΔSOC) based on the current SOC and the target SOC, which is the state of charge (SOC) of the target battery (S113). If it is determined that the current SOC is greater than the set reference SOC, the hybrid controller 240 may generate a first SOC (ΔSOC) by removing as much as the current SOC from the target SOC of the battery (S213). For example, the first SOC (ΔSOC) may be a difference value between a target SOC of the battery and a current SOC.

Subsequently, a compensation factor value is determined based on the generated first SOC (ΔSOC) (S114).

When the compensation factor value is determined, a step of generating the compensation engine target torque by applying the determined compensation factor value to the reference engine target torque (S115). Here, the reference engine target torque may be extracted or calculated based on a predetermined engine target torque reference map or engine target torque reference table.

In addition, it is a step of determining an engine target torque limit value based on the generated first SOC (ΔSOC) (S116). For example, the hybrid controller 240 may receive and compare the generated first SOC (ΔSOC), and set an upper limit torque and a lower limit torque based on the result of the comparison and analysis.

The hybrid controller 240 sets the upper limit torque based on a partial load smaller than the reference load of the reference engine, but may set the partial load as the maximum torque.

In addition, the hybrid controller 240 may set the lower limit torque in consideration of the brake specific fuel consumption (BSFC) of the reference engine.

This is a step of determining an engine output torque command based on the set upper limit torque, the set lower limit torque, and the generated compensation engine target torque (S217). The hybrid controller 240 may determine an engine output torque command based on the set upper limit torque, the set lower limit torque, and the generated compensation engine target torque, and transmit the determined engine output torque command to the engine controller (S118).

The engine controller may control the internal combustion engine based on the transmitted engine output torque command (S119).

As described above, the present invention not only can compensate by considering the SOC when determining the engine target torque so that an appropriate SOC control range can be maintained in a sport mode driving situation under the control of the hybrid controller 240, but also can compensate for the variation of the engine target torque. By controlling it, emission and fuel efficiency performance can be improved.

5 is a flowchart illustrating a method for controlling engine torque of a hybrid vehicle according to another embodiment of the present invention. 6 is a diagram illustrating a torque variation range for a set period according to an embodiment of the present invention.

Referring to FIG. 5 , a method for controlling engine torque of a hybrid vehicle according to another embodiment of the present invention is as follows.

First, it is a step of determining whether to enter a sports mode (S211). According to the present invention, when a sport mode is selected among drive modes, it is possible to enter the sport mode. The present invention may end when an eco mode or a normal mode, not a sports mode, is selected among the drive modes (No in S211).

As a result of the determination, if it is a sports mode, this is a step of comparing the current SOC, which is the state of charge (SOC) of the battery, with a set reference SOC (S212). The reference SOC of the battery may be divided into a plurality of stages according to the range of the SOC, such as critical high, high, normal, low, and critical low. The hybrid controller 240 controls the generation unit 242 to take into consideration the vehicle state information, distance information to the destination, weather information, temperature information, and the mode information determined by the mode determination unit 241 to consider the reference SOC. can be set.

The hybrid controller 240 may be terminated when it is determined that the current SOC is smaller than the set reference SOC (No in S212).

Thereafter, when the current SOC is greater than the reference SOC, generating a first SOC (ΔSOC) based on the current SOC and the target SOC, which is the state of charge (SOC) of the target battery (S213). If it is determined that the current SOC is greater than the set reference SOC, the hybrid controller 240 may generate a first SOC (ΔSOC) by removing as much as the current SOC from the target SOC of the battery (S213). For example, the first SOC (ΔSOC) may be a difference value between a target SOC of the battery and a current SOC.

Subsequently, a compensation factor value is determined based on the generated first SOC (ΔSOC) (S214).

When the compensation factor value is determined, a step of generating the compensation engine target torque by applying the determined compensation factor value to the reference engine target torque (S215). Here, the reference engine target torque may be extracted or calculated based on a predetermined engine target torque reference map or engine target torque reference table.

This is a step of determining whether the generated first SOC (ΔSOC) is included in a preset reference range (Cal.A) (S216).

This is a step of setting the torque variation range differently according to the determination result (S217, S218). The hybrid controller 240 may control the engine torque to be stably implemented by setting a torque variation range differently in response to the determination result.

Referring to FIG. 6 , the hybrid controller 240 determines, as a result of the determination, when the generated first SOC (ΔSOC) includes the preset reference range (Cal.A), the set torque variation range for the first period (α). may be set as the first calibration factor CAL1 and the third calibration factor CAL3 (S117). Here, the torque variation range for the first period (α) may limit the rise or fall rate per unit time based on the first calibration factor (CAL1) and the third calibration factor (CAL3), but this is only an example and is limited thereto It doesn't work.

In addition, as a result of the determination, when the generated first SOC (ΔSOC) is out of the preset reference range (Cal.A), the hybrid controller 240 sets the torque variation range for the second period (β) as a second calibration factor. (CAL2) and the fourth calibration factor (CAL4) can be set (S218). Here, the torque variation range for the second period β may limit the rate of rise or fall per unit time based on the second calibration factor CAL2 and the fourth calibration factor CAL4, but this is only an example and is limited thereto It doesn't work.

The above-described first calibration factor CAL1 to fourth calibration factor CAL4 are data about the driving state of the vehicle, engine torque of the vehicle, ignition angle, compensation engine target torque, torque variation range, etc. under the control of the hybrid controller 240 It may be learned based on at least one of the above, and may be set in consideration of the learned result value. It is not limited thereto, and may be set through a compensation factor map or table according to the generated first SOC (ΔSOC).

Each of the set first calibration factors CAL1 to fourth calibration factors CAL4 may have a predetermined factor. For example, the first calibration factor CAL1 may have a factor smaller than the second calibration factor CAL2, and the third calibration factor CAL3 may have a factor smaller than the fourth calibration factor CAL4. That is, the range of variation between the first calibration factor CAL1 and the third calibration factor CAL3 may be smaller than the range of variation between the second calibration factor CAL2 and the fourth calibration factor CAL4 .

This is a step of setting an engine target torque limit value by applying the set torque variation range to the compensated engine target torque (S219). In the setting step ( S219 ), a limit value may be set in consideration of engine torque change based on the compensation engine target torque. For example, the hybrid controller 240 receives the first calibration factor CAL1, the second calibration factor CAL2, the third calibration factor CAL3, and the fourth calibration factor CAL4, compares and analyzes them, and compares and analyzes the result values An upper limit torque and a lower limit torque can be set based on.

The hybrid controller 240 sets the upper limit torque based on a partial load smaller than the reference load of the reference engine, but may set the partial load as the maximum torque.

In addition, the hybrid controller 240 may set the lower limit torque in consideration of the brake specific fuel consumption (BSFC) of the reference engine.

This is a step of determining an engine output torque command based on the set upper limit torque and the set lower limit torque (S220). The hybrid controller 240 may determine an engine output torque command based on the set upper limit torque and the set lower limit torque, and transmit the determined engine output torque command to the engine controller (S221).

The engine controller may control the internal combustion engine based on the transmitted engine output torque command (S222).

As described above, the present invention not only can compensate by considering the SOC when determining the engine target torque so that an appropriate SOC control range can be maintained in a sport mode driving situation under the control of the hybrid controller 240, but also can compensate for the variation of the engine target torque. By controlling it, emission and fuel efficiency performance can be improved.

7 shows engine torque and driver's requested torque when the battery is charged to the critical high level in SOC. 8 shows the variation of the ignition angle according to the variation of the engine torque. FIG. 9 is an enlarged view illustrating a change in ignition angle of FIG. 8 . 10 is a diagram illustrating an engine control stability securing region.

Referring to FIG. 7 , the hybrid controller 240 may control charging of the battery to be limited when the SOC is charged up to the critical high level in a situation where SOC charge/discharge control is not possible during driving in sports mode. In the graph shown in FIG. 7 , a horizontal direction may represent time, and a vertical direction may represent torque intensity.

At this time, since the output torque of the engine is determined according to the driver's requested torque, smooth torque leveling is not possible and the torque fluctuation between the engine torque and the driver's requested torque increases.

8 and 9, the horizontal direction represents time, and the vertical direction represents engine torque variation and ignition angle variation. The engine torque variation (Δengine torque) may be a difference in engine torque before and after a unit time, and the ignition angle variation (Δignition angle) may be a difference between an engine ignition angle before and after a unit time.

That is, the ignition angle control fluctuation of the engine also increases to cope with the increased torque fluctuation.

In addition, since regenerative braking energy recovery is not possible due to battery charging restrictions, the SOC control range cannot be controlled to an appropriate level, such as deterioration in fuel efficiency. As a result, various performance degradation phenomena mentioned above may occur. To prevent this, the generating unit 242 may set a reference SOC corresponding to the sports mode when driving in the sports mode under the control of the hybrid controller 240 .

Referring to FIG. 10 , the horizontal direction represents engine torque and the vertical direction represents it.

As shown in FIGS. 8 to 10 , the hybrid controller 240 of the present invention provides a first calibration factor CAL1, The second calibration factor CAL2, the third calibration factor CAL3, and the fourth calibration factor CAL4 are provided and compared and analyzed, and the upper limit torque and the lower limit torque may be set based on the result of the comparative analysis.

That is, the hybrid controller may set an upper limit torque and a lower limit torque in consideration of an engine control safety securing region according to engine torque.

As described above, the present invention not only can compensate by considering the SOC when determining the engine target torque so that an appropriate SOC control range can be maintained in the sport mode driving situation, but also controls the variation of the engine target torque, thereby reducing emissions and fuel efficiency. performance can be improved.

The above-described present invention can be implemented as computer readable code on a medium on which a program is recorded. The computer-readable medium includes all types of recording devices in which data that can be read by a computer system is stored. Examples of computer-readable media include Hard Disk Drive (HDD), Solid State Disk (SSD), Silicon Disk Drive (SDD), ROM, RAM, CD-ROM, magnetic tape, floppy disk, optical data storage device, etc. there is

Accordingly, the above detailed description should not be construed as limiting in all respects and should be considered illustrative. The scope of the present invention should be determined by reasonable interpretation of the appended claims, and all changes within the equivalent scope of the present invention are included in the scope of the present invention.

Claims (19)

determining whether to enter a sports mode;
comparing a current state of charge (SOC) of a battery with a set reference SOC, if it is determined that the sport mode is determined as a result of the determination;
generating a first SOC (ΔSOC) based on a target SOC that is a state of charge (SOC) of a target battery and the current SOC when the current SOC is greater than the reference SOC;
determining a compensation factor value based on the generated first SOC (ΔSOC);
generating a compensation engine target torque by applying the determined compensation factor value to a reference engine target torque; and
setting a limit value considering a change in engine torque based on the generated target engine compensation torque;
A method for controlling engine torque of a hybrid vehicle comprising: According to claim 1,
A method for controlling engine torque of a hybrid vehicle, comprising receiving the generated first SOC (ΔSOC), comparing and analyzing the generated first SOC (ΔSOC), and setting an upper limit torque and a lower limit torque based on the result of the comparison and analysis. According to claim 2,
In the setting step,
The upper limit torque is set based on a partial load smaller than the reference load of the reference engine, and the partial load is set as a maximum torque,
An engine torque control method for a hybrid vehicle in which the lower limit torque is set in consideration of a brake specific fuel consumption (BSFC) of a reference engine. According to claim 3,
and determining an engine output torque command based on at least one of the set limit value, the upper limit torque, the lower limit torque, and the compensated engine target torque. According to claim 1,
In the setting step,
When the generated first SOC (ΔSOC) is within a preset reference range (Cal.A), a first period is set;
and setting a second period different from the first period when the generated first SOC (ΔSOC) is out of a preset reference range (Cal.A). According to claim 5,
In the setting step, when the generated first SOC (ΔSOC) includes the preset reference range (Cal.A), the set torque variation range for the first period is divided from the first calibration factor (CAL1). 3 Set the calibration factor (CAL3), or
When the generated first SOC (ΔSOC) is out of the preset reference range (Cal.A), the set torque variation range for the second period is defined as a second calibration factor (CAL2) and a fourth calibration factor (CAL4). A method for controlling engine torque of a hybrid vehicle. According to claim 6,
The first calibration factor CAL1 has a factor smaller than the second calibration factor CAL2, or
The method of controlling engine torque of a hybrid vehicle, wherein the third calibration factor (CAL3) has a factor smaller than the fourth calibration factor (CAL4). According to claim 6,
In the setting step,
The first calibration factor (CAL1), the second calibration factor (CAL2), the third calibration factor (CAL3) and the fourth calibration factor (CAL4) are received and compared and analyzed, and based on the result of the comparative analysis A method for controlling engine torque of a hybrid vehicle by setting an upper limit torque and a lower limit torque. According to claim 8,
The upper limit torque is,
Based on a partial load smaller than the reference load of the reference engine, setting the partial load as a maximum torque or controlling engine torque of a hybrid vehicle.
The lower limit torque is,
An engine torque control method for a hybrid vehicle, which is set in consideration of a brake specific fuel consumption (BSFC) of the reference engine. A computer readable recording medium recording a program for executing the method for controlling engine torque of a hybrid vehicle according to any one of claims 1 to 9. In a hybrid vehicle having a controller,
The controller,
a mode determination unit determining whether to enter a sports mode;
As a result of the determination, if it is the sports mode, the current SOC, which is the current state of charge (SOC) of the battery, is compared with a set reference SOC, and if the current SOC is greater than the reference SOC, the target battery's state of charge (SOC) ), a generator for generating a first SOC (ΔSOC) based on the target SOC and the current SOC;
A compensation factor value is determined based on the generated first SOC (ΔSOC), a compensation engine target torque is generated by applying the determined compensation factor value to a reference engine target torque, and based on the generated compensation engine target torque a setting unit for setting a limit value considering engine torque change;
Including, a hybrid vehicle. According to claim 11,
The setting unit,
The hybrid vehicle receives the generated first SOC (ΔSOC), compares and analyzes it, and sets an upper limit torque and a lower limit torque based on the result of the comparison and analysis. According to claim 12,
The setting unit,
The upper limit torque is set based on a partial load smaller than the reference load of the reference engine, and the partial load is set as a maximum torque,
A hybrid vehicle in which the lower limit torque is set in consideration of the brake specific fuel consumption (BSFC) of the reference engine. According to claim 13,
The controller,
and a determination unit that determines an engine output torque command based on at least one of the set limit value, the upper limit torque, the lower limit torque, and the compensation engine target torque. According to claim 11,
The setting unit,
When the generated first SOC (ΔSOC) is within the preset reference range (Cal.A), the first period is set, and the generated first SOC (ΔSOC) falls within the preset reference range (Cal.A). If it deviates, the hybrid vehicle sets a second period different from the first period. According to claim 15,
The setting unit,
When the generated first SOC (ΔSOC) includes a preset reference range (Cal.A), the set torque variation range for the first period is determined by a first calibration factor (CAL1) and a third calibration factor (CAL3) , or when the generated first SOC (ΔSOC) is out of the preset reference range (Cal.A), the set torque variation range for the second period is set by the second calibration factor (CAL2) and the fourth calibration factor (CAL4), hybrid car. According to claim 16,
The first calibration factor CAL1 has a factor smaller than the second calibration factor CAL2, or
The hybrid vehicle, wherein the third calibration factor (CAL3) has a factor smaller than the fourth calibration factor (CAL4). According to claim 13,
The setting unit,
The first calibration factor (CAL1), the second calibration factor (CAL2), the third calibration factor (CAL3) and the fourth calibration factor (CAL4) are received and compared and analyzed, and based on the result of the comparative analysis A hybrid vehicle in which upper limit torque and lower limit torque are set. According to claim 17,
The setting unit,
Set the upper limit torque as a maximum torque based on a partial load smaller than the reference load of the reference engine,
The hybrid vehicle, wherein the lower limit torque is set in consideration of a Brake Specific Fuel Consumption (BSFC) of the reference engine.