Method for setting electric vehicle on/off line of hybrid vehicle

Patent metadata

Field	Value
Publication number	US-10988046-B2
Application number	US-201715838872-A
Country	US
Kind code	B2
Filing date	Dec 12, 2017
Priority date	Oct 11, 2017
Publication date	Apr 27, 2021
Grant date	Apr 27, 2021

Abstract

A method for setting an electric vehicle (EV) on/off line of a hybrid vehicle considers a driving load of the vehicle by setting the EV on/off line based on a climbing angle and creep power. The method for setting the EV on/off line of the hybrid vehicle includes an operation of setting a region according to a state of charge (SOC), an EV online setting operation based on a climbing angle of the vehicle, and an EV offline setting operation based on creep power of the vehicle. The method provides a simple and intuitive EV line setting method to reduce a mapping time and substantially eliminate the possibility of human error, thus increasing logic reliability, so as to reduce use of a hybrid control unit (HCU) memory and provide cost-saving effects.

First claim

What is claimed is:

1. A method for setting an electric vehicle (EV) on/off line of a hybrid vehicle comprising:
performing, by a controller, an operation of setting a region according to a state of charge (SOC);
performing, by the controller, an EV online setting operation based on a climbing angle of the vehicle; and
performing, by the controller, an EV offline setting operation based on creep power of the vehicle,
wherein the EV online setting operation turns on an engine of the vehicle when driving power exceeding an EV online is required while the hybrid vehicle drives in an EV driving mode and the EV offline setting operation turns off the engine when the driving power that is equal to or less than an EV offline is required while the hybrid vehicle drives in an HEV driving mode,
wherein the EV offline setting operation sequentially performs a creep-power determination operation, a critical low EV offline determination operation, and an operation of determining an EV offline for an SOC region determined according to the predetermined factor based on the critical low EV offline, and
wherein the critical low EV offline determination operation determines a critical low EV offline a value obtained by adding margin to the creep power determined at the creep-power determination operation.

2. The method of claim 1 , wherein the operation of setting the region according to the SOC sets a whole region as seven stages, including a critical low stage, a low stage, a normal low stage, a normal stage, a normal high stage, a high stage, and a critical high stage in order of level of the SOC.

3. The method of claim 2 , wherein each of the normal low stage and the normal high stage is again subdivided into three stages.

4. The method of claim 1 , wherein the EV online setting operation comprises an operation of calculating a climbing angle that allows driving only with an engine, a weight-factor determination operation, a normal EV online reference determination operation considering a weight factor, and an EV online determination operation according to a SOC region, the operations being sequentially performed.

5. The method of claim 4 , wherein the step of calculating the climbing angle that allows driving only with the engine sequentially performs determination of an engine optimal operating line according to an engine speed, determination of a number of speed-changing operation for a vehicle speed according to the engine optimal operating line, determination of engine power, determination of driving resistance, calculation of the climbing angle, and setting of reference driving power of a SOC normal region.

6. The method of claim 5 , wherein the engine power is determined by the following equation:
engine power=engine optimal operating line×engine speed.

7. The method of claim 5 , wherein the driving resistance is determined by the following equation:
driving resistance= f 0 +f 1 v+f 2 v 2
where f 0 , f 1 and f 2 represent driving resistance coefficients, and v represents a vehicle speed (km/h).

8. The method of claim 5 , wherein the climbing angle is determined by the following equation:

climbing
⁢

⁢
angle
⁢

⁢

(
%
)

=

(

engine
⁢

⁢
power
×

transmission
⁢

⁢
efficiency
⁢

×

drivetrain
⁢

⁢
loss
×

v
3.6

-

driving
⁢

⁢
resistance

)

ℊ
×
m

×
100

where g represents gravitational acceleration (m/s 2 ), m represents a weight (kg), and v represents a vehicle speed (km/h).

9. The method of claim 4 , wherein, at the weight-factor determination operation, the weight factor (F m ) is determined by the following equation:

F
m

=

1
+

(

reference
⁢

⁢
weight

-
weight

)

reference
⁢

⁢
weight

×
α

where α represents a weight-factor coefficient.

10. A non-transitory computer readable medium containing program instructions executed by a processor, the computer readable medium comprising:
 program instructions that set an electric vehicle (EV) on/off line of a hybrid vehicle, comprising:
 program instructions that set a region according to a state of charge (SOC);
 progr

Assignees

• Hyundai Motor Co Ltd
• Kia Motors Corp

Inventors

• Huh Jee-Wook
• Park Seong-Ik
• Lee Chun-Hyuk
• Oh Kyoung-Cheol

Classifications

• Y02T10/62

  Hybrid vehicles · CPC title

• B60W2552/15

  Road slope, i.e. the inclination of a road segment in the longitudinal direction · CPC title

• B60W20/10 Primary

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

• B60W2710/0644

  Engine speed · CPC title

• B60W40/13

  Load or weight · CPC title