System and method for controlling compressor of vehicle

Patent metadata

Field	Value
Publication number	US-2019389279-A1
Application number	US-201816159379-A
Country	US
Kind code	A1
Filing date	Oct 12, 2018
Priority date	Jun 24, 2018
Publication date	Dec 26, 2019
Grant date	—

Abstract

A system for controlling a compressor may include an engine controller controlling a fuel injection amount corresponding to an engine load and an opening amount of a throttle by reflecting a required torque required for an air conditioner, an operation information detector for detecting operation information according to driving state of the vehicle, a compressor generating pressure through a piston operation of a cylinder utilizing the power of the engine during operation of the air conditioner, and a controller determining an engine negative pressure of an intake manifold stored in the brake booster at a value, and when the negative pressure of intake manifold is below a first threshold value when the brake is operated, the engine enters a negative pressure recovery mode for predicting an insignificant negative pressure drop condition that falls below a second threshold value which is the A/C cut control condition and reduces the A/C duty.

First claim

What is claimed is:

1 . A system for controlling a compressor of a vehicle, comprising:
an engine controller (ECU) that controls a fuel injection amount corresponding to an engine load and an opening amount of a throttle according to a required torque required for an air conditioner (A/C); an operation information detector connected to the ECU and configured for detecting operation information according to driving state of the vehicle; a compressor that generates pressure through operation of a piston in a cylinder utilizing power of an engine during operation of the A/C; and a controller which is connected to the ECU and determines a negative pressure of an intake manifold stored in a brake booster at a value obtained by subtracting the negative pressure from atmospheric pressure detected by the operation information detector, wherein while the negative pressure of the intake manifold is below a first threshold value when a brake is operated, the engine enters a negative pressure recovery mode for predicting an insignificant negative pressure drop condition that falls below a second threshold value which is an A/C cut control condition and reduces an A/C duty of the compressor.

2 . The system for controlling the compressor of the vehicle of claim 1 , wherein the compressor includes a pressure regulator for regulating an operation rate of the piston by changing an angle of a swash plate in accordance with an A/C duty control signal applied from the controller.

3 . The system for controlling the compressor of the vehicle of claim 1 , further including:
a memory for storing an A/C duty control map for variable A/C duty control of the compressor and a required torque control map corresponding to the A/C duty control map in a case of insignificant negative pressure of the intake manifold.

4 . The system for controlling the compressor of the vehicle of claim 1 , wherein the operation information detector detects at least one operation information among air conditioner operation state, vehicle speed, atmospheric pressure, inflation pressure, accelerator pedal operation state, brake operation state, sea level, road inclination, and a timer.

5 . The system for controlling the compressor of the vehicle of claim 1 , wherein the controller enters the negative pressure recovery mode when the vehicle is running at a speed lower than a predetermined vehicle speed at which the vehicle is not completely stopped based on the detected operation information, the negative pressure of the intake manifold is lower than the first threshold value, an accelerator pedal is not operated, and a brake is operated.

6 . The system for controlling the compressor of the vehicle of claim 1 , wherein the controller reduces a basic A/C duty according to entry into the negative pressure recovery mode to a minimum A/C duty for a predetermined time period to reduce the engine load and then returns to the basic A/C duty.

7 . The system for controlling the compressor of the vehicle of claim 6 , wherein the controller controls a variation rate of a release slope returning to the basic A/C duty compared to a change rate of the entering slope which is reduced to a minimum A/C duty during a present time upon entering the negative pressure recovery mode.

8 . The system for controlling the compressor of the vehicle of claim 6 , wherein the controller prohibits re-entry into the negative pressure recovery mode within a predetermined re-entry prohibition time period after returning to the basic A/C duty.

9 . The system for controlling the compressor of the vehicle of claim 1 , wherein the controller performs a required torque control to determine a required torque reduction amount of the compressor with an A/C duty reduction control and send the determined required torque reduction amount to the ECU when entering the negative pressure recovery mode.

10 . The system for controlling the compressor of the vehicle of claim 9 , wherein the controller, by referring to a first required torque control table in which the required torque control amount which is reduced to a minimum output is quantitatively different in correspondence with an output value for each A/C duty before entering the negative pressure recovery mode, outputs a reduced torque demand to the ECU by subtracting a first required torque control amount from the output value.

11 . The system for controlling the compressor of the vehicle of claim 9 , wherein the controller, by referring to a second required torque control table in which the required torque control amount that is reduced to the minimum output is quantitatively different in correspondence with the output value for each A/C duty before entering the negative pressure recovery mode, outputs the reduced torque demand to the ECU by subtracting the second required torque control amount from the output value.

12 . The system for controlling the compressor of the vehicle of claim 10 , wherein the controller selects a large value among the first required torque control amount and the second required torque control amount, and transmits the reduced torque demand to the ECU.

13 . The system for controlling the compressor of the vehicle of claim 1 , wherein the controller restricts an entry into the negative pressure recovery mode when the vehicle is in a mounting state at a predetermined inclination or more or at a highland higher than a predetermined altitude.

14 . The system for controlling the compressor of the vehicle of claim 1 , wherein the controller shortens variable sets of the first threshold value to increase as an altitude at which the vehicle is located at a flatland below a predetermined altitude to shorten a point of entry of negative pressure recovery mode.

15 . A method for controlling a compressor of a vehicle according to a brake negative pressure condition of a vehicle compressor control system, comprising:
a) controlling, by a controller, the compressor with a set basic A/C duty when an air conditioner (A/C) of the vehicle is operated; b) determining, by the controller, a negative pressure of an intake manifold stored in a brake booster at a value obtained by collecting operation information according to a running state of the vehicle and subtracting an intake manifold pressure from an atmospheric pressure; c) entering, by the controller, a negative pressure recovery mode when braking operation is in a state where the negative pressure of the intake manifold is less than a first threshold value; and d) performing, by the controller, negative pressure recovery control for reducing an engine load by reducing the basic A/C duty according to an entry into the negative pressure recovery mode to a minimum A/C duty for a predetermined time period.

16 . The method for controlling the compressor of the vehicle of claim 15 , wherein the step c) includes:
entering the negative pressure recovery mode when the vehicle is running at a speed lower than a predetermined vehicle speed at which the vehicle is not completely stopped based on the collected operation information, an accelerator pedal is not operated, and a brake is operated.

17 . The method for controlling the compressor of the vehicle of claim 15 , wherein the step c) further includes:
entering the negative pressure recovery mode when a fluctuation rate of the negative pressure of the intake manifold detected during a predetermined time period is changed to be equal to or greater than a third threshold value when a condition in which the negative pressure of the intake manifold is not more than the first threshold is n

Assignees

• Hyundai Motor Co Ltd
• Kia Motors Corp

Inventors

• Jung Tae Hun
• Seo Jeong Sik
• Moon Jaeyeon

Classifications

• F02D2250/41

  Control to generate negative pressure in the intake manifold, e.g. for fuel vapor purging or brake booster · CPC title

• F02D2200/70

  said parameters being related to the vehicle exterior · CPC title

• F02D2200/0406

  Intake manifold pressure · CPC title

• F02D41/0005

  during deceleration · CPC title

• F02D41/0002 Primary

  Controlling intake air · CPC title