Non-uniform displacement engine control system with different control modes based on state of charge of battery and method for controlling non-uniform displacement engine with different control modes based on state of charge of battery

Patent metadata

Field	Value
Publication number	US-10041423-B2
Application number	US-201615266680-A
Country	US
Kind code	B2
Filing date	Sep 15, 2016
Priority date	Sep 17, 2015
Publication date	Aug 7, 2018
Grant date	Aug 7, 2018

Abstract

A non-uniform displacement engine control system with different control modes based on a state of charge (SOC) of a battery, the system includes a non-uniform displacement engine including a plurality of cylinders, the cylinders comprising at least two sizes of cylinders having different displacements, a motor connected to a driving shaft of the engine, a battery for supplying electrical energy to the motor, and a motor control device for controlling the motor, wherein the motor control device controls the motor to compensate for a difference in torque due to different displacements of the cylinders such that a sum of engine torque and motor torque in explosion stroke of each cylinder is uniform, and the motor control device has a charge intention mode or a discharge intention mode based on the SOC of the battery.

First claim

What is claimed is:

1. A non-uniform displacement engine control system with different control modes based on a state of charge (SOC) of a battery, the system comprising:
a non-uniform displacement engine including a plurality of cylinders, the cylinders comprising at least two sizes of cylinders having different displacements;
a motor connected to a driving shaft of the engine;
a battery for supplying electrical energy to the motor; and
a motor control device for controlling the motor, wherein
the motor control device controls the motor to compensate for a difference in torque due to different displacements of the cylinders such that a sum of engine torque and motor torque in explosion stroke of each cylinder is uniform, and
the motor control device has a charge intention mode or a discharge intention mode based on the SOC of the battery, and
the motor control device having at least two control modes, the respective control modes configured to have different total driving torques by adjusting a motor assist torque and a motor regenerative torque in accordance with the engine torque such that the driving torque is varied by changing the control mode,
wherein the motor assist torque and the motor regenerative torque are predetermined to compensate the torque difference due to different displacements of the cylinders and the control modes are stored in the motor control device,
wherein each of the control modes has a predetermined target displacement being different from each other and the motor assist torque and the motor regenerative torque are predetermined based on the target displacement,
wherein a variable displacement control is performed by changing the control mode.

2. The system of claim 1 , wherein the motor control device performs control to reduce a discharge amount due to driving of the motor based on the SOC of the battery in the charge intention mode and to reduce a charge amount due to energy regeneration in the discharge intention mode.

3. The system of claim 1 , wherein the charge intention mode or the discharge intention mode is temporarily applied until the SOC of the battery reaches a predetermined reference value.

4. The system of claim 1 , wherein the motor control device applies a compensation coefficient (α<1) for motor driving torque in the charge intention mode and a compensation coefficient (β<1) for regenerative torque in the discharge intention mode.

5. The system of claim 4 , wherein the compensation coefficients are fixed values or values preset so as to vary based on the SOC of the battery.

6. The system of claim 1 , wherein the motor control device controls the motor based on the discharge intention mode when the SOC of the battery is equal to or greater than a predetermined upper limit value and controls the motor based on the charge intention mode when the SOC of the battery is equal to or less than a predetermined lower limit value.

7. The system of claim 6 , wherein the motor control device performs controls to terminate the discharge intention mode when the SOC of the battery reaches a predetermined reference value in the discharge intention mode and to terminate the charge intention mode when the SOC of the battery reaches the predetermined reference value in the charge intention mode, and controls the motor such that the sum of the engine torque and the motor torque is uniform when the discharge intention mode or the charge intention mode is terminated.

8. The system of claim 1 , wherein the non-uniform displacement engine comprises two sets of cylinders, each set of cylinders comprising at least two cylinders having the same displacement.

9. The system of claim 1 , wherein the non-uniform displacement engine is configured such that first and fourth cylinders have a higher displacement than second and third cylinders, and each set of cylinders alternately performs an explosion stroke.

10. The system of claim 1 , wherein
the non-uniform displacement engine comprises two sizes of cylinders having different displacements, and
the motor control device comprises a mode for controlling the motor such that energy recuperation is achieved in explosion strokes of high displacement cylinders and controlling the motor such that power assistance is achieved by the motor torque in explosion strokes of low displacement cylinders such that the sum of the engine torque and the motor torque in the explosion stroke of each cylinder is uniform.

11. A control method of a system comprising a non-uniform displacement engine including a plurality of cylinders, the cylinders including at least two sizes of cylinders having different displacements, and a motor connected to a driving shaft of the engine, the method comprising:
driving the non-uniform displacement engine;
determining motor torque based on engine torque; and
controlling the motor based on the determined motor torque,
wherein the determining step includes compensating for a difference in torque due to the cylinders having different displacements to control the motor such that a sum of the engine torque and the motor torque in explosion strokes of each cylinder is uniform and having a charge intention mode or a discharge intention mode based on an SOC of a battery, and
wherein the motor is controlled by a motor control device which has at least two control modes, and the motor torque is determined by the control modes; and
the respective control modes are configured to have different total driving torques by adjusting a motor assist torque and a motor regenerative torque in accordance with the engine torque such that the driving torque is varied by changing the control mode,
wherein the motor assist torque and the motor regenerative torque are predetermined to compensate the torque difference due to different displacements of the cylinders and the control modes are stored in the motor control device,
wherein each of the control modes has a predetermined target displacement being different from each other and the motor assist torque and the motor regenerative torque are predetermined based on the target displacement,
wherein a variable displacement control is performed by changing the control mode.

12. The method of claim 11 , wherein control is performed to reduce a discharge amount due to driving of the motor based on the SOC of the battery in the charge intention mode and to reduce a charge amount due to energy regeneration in the discharge intention mode.

13. The method of claim 11 , wherein the charge intention mode or the discharge intention mode is temporarily applied until the SOC of the battery reaches a predetermined reference value.

14. The method of claim 11 , wherein a compensation coefficient (α<1) for motor driving torque is applied in the charge intention mode, and a compensation coefficient (β<1) for regenerative torque is applied in the discharge intention mode.

15. The method of claim 14 , wherein the compensation coefficients are fixed values or values preset so as to vary based on the SOC of the battery.

16. The method of claim 11 , wherein the determining step includes controlling the motor based on the discharge intention mode when the SOC of the battery is equal to or greater than a predetermined upper limit value and controlling the motor based on the charge intention mode when the SOC of the battery is equal to or less than a predetermined lower limit value.

17. The method of claim 16 , wherein control is performed to terminate the discharge intention mode when the SOC of the battery reaches a predetermined reference value in the discharge intention mode and to

Assignees

• Hyundai Motor Co Ltd

Inventors

• Eo Jeong Soo
• Kim Yeon Bok
• Jung Youn Kwang
• Kim Sung Jae
• Chang Young Joon

Classifications

• F02N2200/061

  Battery state of charge [SOC] · CPC title

• B60W10/08

  including control of electric propulsion units, e.g. motors or generators · CPC title

• F02D2250/28

  Control for reducing torsional vibrations, e.g. at acceleration · CPC title

• B60W2030/206

  related or induced by the engine · CPC title

• B60W20/10 Primary

  Controlling the power contribution of each of the prime movers to meet required power demand · CPC title