Patent Application
20160102598
This application claims the benefit of priority to Korean Patent Application No. 10-2014-0136124 filed in the Korean Intellectual Property Office on Oct. 8, 2014, the entire contents of which are incorporated herein by reference.
The present invention relates to a method and system for controlling an electric water pump (EWP), and more particularly, to a method and system for controlling an electric water pump that may be effectively controlled by separating a control signal for operation of the electric water pump from a power signal and by using a digital signal outputted from an engine electronic control unit (ECU).
As is well-known to a person of an ordinary skill in the art, an EWP is a pump that is independently operated or driven by a motor without depending on power of an engine, while a mechanical water pump depends on power of an engine.
Since the EWP is independently controlled to supply a coolant flow rate suitable for a driving condition of an engine or a vehicle regardless of operation of the engine, the EWP has the following merits.
First, since it is not needed for the EWP to operate during an initial operating period of an engine, the engine can be rapidly warmed.
Second, a ratio of power of the EWP to power of a mechanical water pump may be about 60-70%.
Third, since the EWP is operated by power of a motor, a cooling system of a vehicle may be compacted.
However, according to the related art, since the EWP is controlled through only ignition (IG) power and a controller area network (CAN) signal outputted from an ECU, the EWP operates only in a limp-home mode when the CAN signal is unstable.
In other words, according to the conventional EWP control method, when the EWP operates abnormally, the EWP may not be effectively used.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.
(Patent Document 1) Patent Laid-Open Publication No. KR 10-2008-0035263 (Apr. 23, 2008)
(Patent Document 2) Patent Laid-Open Publication No. KR 10-2012-0140412 (Dec. 31, 2012)
Accordingly, the present disclosure has been made in an effort to provide a method and system for controlling an EWP that may effectively perform fail-safe control and driving control for the EWP by separating a control signal for operation of the EWP from a power signal and by using a digital signal outputted from an ECU.
For this purpose, an exemplary embodiment of the present invention provides a method of controlling an EWP through an EWP controller configured to communicate with an ECU on a controller area network (CAN). The method may include: receiving a CAN signal from the ECU to control the EWP through the CAN; receiving a fail-safe digital signal (FSDS) that is related to a fail-safe control function of an engine or the EWP from the ECU; and controlling the EWP based on the CAN signal and the fail-safe digital signal.
In certain embodiments, the EWP may include an auxiliary EWP which cools a heater, a turbocharger, and an inverter. In certain embodiments, the method may further include detecting battery power that is supplied to the EWP by a battery or ignition (IG) power that is supplied to the EWP by an IG power portion.
In certain embodiments, the method may further include receiving a rotation speed command for the EWP from the ECU through the CAN.
In certain embodiments, when the IG power is turned on and the CAN signal is normal, the EWP may be controlled based on commands from the ECU.
In certain embodiments, when the IG power is turned on and the FSDS is normally inputted to the EWP controller while the CAN signal is not inputted to the EWP controller, the EWP may be controlled in the limp-home mode.
In certain embodiments, when the IG power is turned on and the FSDS is not normally inputted to the EWP controller while the CAN signal is not inputted to the EWP controller, the EWP may be controlled in the wake-up mode.
In certain embodiments, when the IG power is turned off and the CAN signal is normally inputted to the EWP controller, the EWP may be controlled based on commands from the ECU, and when the IG power is turned off and the CAN signal is not normally inputted to the EWP controller, the EWP may be set to enter a sleep mode.
In certain embodiments, when the EWP is set to enter the sleep mode from the normal mode, the sleep mode may be performed after a predetermined time has passed.
Another embodiment of the present invention provides a system for controlling an EWP, including: an ECU configured to control an engine; an EWP configured to cool the engine; a battery configured to supply the EWP with battery power (B+); an ignition power portion configured to supply the EWP with ignition (IG) power. An EWP controller is configured to communicate with the ECU on a controller area network (CAN), receive a CAN signal from the ECU to control the EWP through the CAN, receive a fail-safe digital signal (FSDS) from the ECU, and control the EWP based on the CAN signal and the FSDS.
In certain embodiments, the EWP may include an auxiliary EWP which cools a heater, a turbocharger, and an inverter. In certain embodiments, the EWP controller may be further configured to detect the battery power that is supplied to the EWP by the battery or the IG power supplied by the IG power portion. In certain embodiments, the EWP controller may be further configured to receive a rotation speed command for the EWP from the ECU through the CAN.
Another embodiment provides a computer readable storage medium containing a computer program configured to cause an EWP controller to control an electric water pump (EWP) by the following method when read and processed by a computer system: receiving a controller area network (CAN) signal from an engine electronic control unit (ECU) to control the EWP through a controller area network (CAN); receiving a fail-safe digital signal (FSDS) that is related to a fail-safe control function of an engine or the EWP from the ECU; and controlling the EWP based on the CAN signal and the fail-safe digital signal.
As described above, according to an embodiment of the present invention, the method and system for controlling an EWP can be provided to effectively control the EWP by separating a control signal for the EWP from a power signal and by using a digital signal outputted from the ECU.
Embodiments of the present invention will be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments of the invention are shown. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention.
In addition, in the specification, unless explicitly described to the contrary, the word “comprise” and variations such as “comprises” or “comprising” will be understood to imply the inclusion of stated elements but not the exclusion of any other elements.
The system for controlling the EWP according to an exemplary embodiment of the present invention may control the EWP by separating a control signal for operation of the EWP from a power signal, and by using a digital signal outputted from the ECU.
A system for controlling the EWP according to an exemplary embodiment of the present invention includes: an ECU 100 configured to control an engine 1; an EWP 30 configured to cool the engine 1; a battery 10 configured to supply the EWP 30 with battery power (B+); an ignition power portion 20 configured to supply the EWP 30 with ignition (IG) power; and an EWP controller 200 configured to communicate with the ECU 100 on a controller area network
(CAN). The EWP controller may be configured to receive a CAN signal from the ECU to control the EWP through the CAN, receive a fail-safe digital signal (FSDS) from the ECU, and control the EWP based on the CAN signal and the FSDS. In certain embodiments, the EWP controller is further configured to perform a normal mode, a limp-home mode, a sleep mode, and a wake-up mode, to receive a fail-safe digital signal (FSDS) from the ECU 100, and to perform fail-safe control and driving control for the EWP 30. The EWP controller may also perform other control functions of the EWP. The EWP 30 may include an auxiliary EWP (not shown) which cools a heater, a turbocharger, and an inverter.
The battery power and the ignition (IG) power may be directly supplied to the EWP 30 from the battery 10 and the IG power portion 20 as powers for driving the EWP 30.
The battery power and the ignition (IG) power are supplied to the EWP controller 200, and the EWP controller 200 detects the powers that are supplied to the EWP 30 from the battery 10 and the IG power portion 20.
The EWP controller 200 may receive a command such as a rotation speed command for the EWP 30, and various kinds of commands through the CAN from the ECU 100.
In the exemplary embodiment of the present invention, the engine 1, the battery 10, the IG power portion 20, and the EWP 30 may be those typically applied in the related art, so the detailed descriptions thereof will be omitted in the present specification.
The EWP controller 200 may include one or more processors or microprocessors, and/or hardware operated by a predetermined program including a series of commands for executing a method of controlling the EWP according to an exemplary embodiment of the present invention, which will be described below.
Hereinafter, a method of controlling the EWP according to an exemplary embodiment of the present invention will be described in detail with reference to the accompanying drawings.
As shown in
In certain embodiments, when the IG power is turned on (S110) and the CAN signal is normal (S120), since the EWP controller 200 may control the EWP 30 regardless of the FSDS signal (S130), the EWP controller 200 normally controls the EWP 30 based on commands for operation of the EWP 30 outputted from the ECU 100 (S210).
In certain embodiments, when the CAN signal is abnormal as the CAN signal is interrupted at step S120 and the FSDS signal is normally inputted to the EWP controller 200 (S125), the EWP controller 200 controls the EWP 30 in the limp-home mode (S220). In other words, in this case, even though the EWP 30 can be operated, since no normal control signal exists due to an interruption of the CAN signal, the limp-home mode is performed.
In certain embodiments, when the FSDS signal is off at step S125, since this case is a condition such as no normal CAN signal exists due to, for example, cutting of a wire for the FSDS signal, the EWP controller 200 controls the EWP 30 in the wake-up mode (S230).
In certain embodiments, when the IG power is turned off at step S110 and the CAN signal is normally inputted to the EWP controller 200 (S150), this is a case of the CAN signal being normally received and transmitted to and from the EWP controller 200. Accordingly, regardless of the FSDS signal (S160), the EWP controller 200 controls the EWP 30 in the normal mode based on the commands from the ECU 100 (S240).
In certain embodiments, when the CAN signal is not normally inputted to the EWP controller 200 at step S150, this is a case of a control signal for controlling the EWP 30 not existing. Accordingly, regardless of the FSDS signal (S155), the EWP controller 200 controls the EWP 30 in the sleep mode (S250).
Referring to
Accordingly, accordingly to the exemplary embodiment of the present invention, the EWP may be effectively controlled by separating the control signal for operation of the EWP from the power signal and by using the digital signal outputted from the ECU.
While practical exemplary embodiments of this invention have been described above, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2014-0136124 | Oct 2014 | KR | national |
