Method for controlling an injector in a common rail system
AssigneeVitesco Technologies GmbH
InventorsEdouard Gambier, Johann Ratinaud, Quentin Dussardier
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Abstract
The invention relates to a method for controlling an injector in a common rail system, comprising the following steps: detecting (E2) an increase between an observed static flow rate and a reference static flow rate and determining (E3) a corrected rail-pressure setpoint (Pcor) guaranteeing the same quantity of fluid injected with the observed static flow rate as that injected with a reference pressure (Pref) and the reference static flow rate. The invention thus advantageously makes it possible to maintain the same duration of injection.
Claims13
A method implemented by a controller that controls a common rail system for an internal combustion engine, comprising:
- injecting a predetermined quantity of fluid through an injector of the common rail system, the predetermined quantity of fluid being injected at a reference rail pressure and having a predetermined mass, and being injected for a predetermined duration of time;
- determining an instant static flow rate, as an observed static flow rate, of the predetermined mass of fluid injected through the injector;
- determining whether the observed static flow rate is greater than a reference static flow rate for the injector;
- and
- when the observed static flow rate is determined to be greater than the reference static flow rate,
- determining a corrected rail pressure for causing the rail system to inject said predetermined mass of the fluid through the injector with the observed static flow rate and with said predetermined duration of time, and
- controlling the rail system to inject another quantity of the fluid, having a mass equal to the predetermined mass, through the injector at the corrected rail pressure, the injector controlled to be open for injecting the fluid for a duration equal to the predetermined duration of time,
- where the corrected rail pressure is determined by computing a difference between the reference pressure and a predetermined pressure value that corresponds to the observed static flow rate for the injector, and adding said difference to the reference value.
A method implemented by a controller that controls a common rail system for an internal combustion engine, comprising:
- injecting a predetermined quantity of fluid through an injector of the common rail system, the predetermined quantity of fluid being injected at a reference rail pressure and having a predetermined mass, and being injected for a predetermined duration of time;
- determining an instant static flow rate, as an observed static flow rate, of the predetermined mass of fluid injected through the injector;
- determining whether the observed static flow rate is greater than a reference static flow rate for the injector;
- and
- when the observed static flow rate is determined to be greater than the reference static flow rate,
- determining a corrected rail pressure for causing the rail system to inject said predetermined mass of the fluid through the injector with the observed static flow rate and with said predetermined duration of time, and
- controlling the rail system to inject another quantity of the fluid, having a mass equal to the predetermined mass, through the injector at the corrected rail pressure, the injector controlled to be open for injecting the fluid for a duration equal to the predetermined duration of time,
- where the corrected pressure is determined according to
- Pcor
- =
- ρ
-
- (
- P
-
- ref
- ,
- T
- )
- ·
- (
- Pref
- -
- Pcyl
- )
- ρ
-
- (
- P
-
- cor
- ,
- T
- )
- ·
- R
- 2
- +
- P
-
- c
-
- y
-
- l
- where Pcor is the corrected rail pressure, ρ is a density of the injected fluid, Pref is the reference pressure, T is a temperature of the injected fluid, Pcyl is a pressure in the cylinder, and R is a ratio of the observed static flow rate to the reference static flow rate.
Dependencies are inferred from the claim text.