Method for torque control of an internal combustion engine, and internal combustion engine

Patent metadata

Field	Value
Publication number	US-9617934-B2
Application number	US-201514683751-A
Country	US
Kind code	B2
Filing date	Apr 10, 2015
Priority date	Oct 10, 2012
Publication date	Apr 11, 2017
Grant date	Apr 11, 2017

Abstract

A method for torque control of an internal combustion engine includes a pressure sensor that is associated with at least one, but at the most two cylinders of the internal combustion engine, whereby an cylinder internal pressure for the cylinder associated with the pressure sensor is detected. The method carries out an adjustment of injection characteristics for the injectors allocated to the individual cylinders of the internal combustion engine by way of a method which is independent from the detected cylinder pressure. A torque control for the internal combustion engine is performed based on the detected cylinder pressure.

First claim

What is claimed is:

1. An internal combustion engine having a plurality of cylinders, wherein:
at least one pressure sensor is assigned to between one and two of said plurality of cylinders;
said internal combustion engine having an engine control unit, said engine control unit implementing a series of steps, said series of steps comprising:
detecting an internal cylinder pressure for said between one and two cylinders of said internal combustion engine using said at least one pressure sensor;
adjusting a number of injectors assigned to a number of said plurality of cylinders of said internal combustion engine to be equal in regard to their injection behavior independently from said detected internal cylinder pressure; and
performing a torque control of said internal combustion engine on the basis of said detected internal cylinder pressure.

2. The internal combustion engine according to claim 1 , wherein:
said internal combustion engine is designed as a V-engine, having two V-shaped cylinder banks arranged at an angle relative to each other, each cylinder bank including precisely one cylinder to which a pressure sensor is assigned.

3. The internal combustion engine according to claim 1 , wherein:
a pressure sensor is assigned to precisely one cylinder of said internal combustion engine.

4. A method for torque control of an internal combustion engine, including the steps of:
assigning at least one pressure sensor to between one and two cylinders of said internal combustion engine;
detecting an internal cylinder pressure for said between one and two cylinders of said internal combustion engine using said at least one pressure sensor;
adjusting a number of injectors assigned to a number of cylinders of said internal combustion engine to be equal in regard to their injection behavior independently from said detected internal cylinder pressure; and
performing a torque control of said internal combustion engine on the basis of said detected internal cylinder pressure.

5. The method according to claim 4 , wherein:
said internal combustion engine being a V-engine, said V-engine having two cylinder banks arranged at an angle relative to each other, each of said cylinder banks having exactly one cylinder to which one pressure sensor is assigned.

6. The method according to claim 4 , wherein:
exactly one pressure sensor is used.

7. The method according to claim 4 , wherein:
said step of adjusting a number of injectors assigned to a number of cylinders of said internal combustion engine to be equal in regard to their injection behavior further comprises the sub-steps of:
turning off one of said number of injectors;
capturing a crank angle signal from said internal combustion engine;
converting said crank angle signal into a frequency range using a discrete Fourier transformation;
capturing and storing an amount of a harmonic of the 0.5th order of said Fourier transformation of said crank angle signal;
assigning said amount to said turned off injector;
turning on said turned off injector;
performing each previous sub-step in a sequential manner for each injector of said internal combustion engine;
creating a mean value of said stored amounts over all of said injectors; and
correcting a control of said injectors based on a deviation of said amount from said mean value assigned to an injector that is to be corrected.

8. The method according to claim 4 , further comprising the steps of:
calculating for each said injector a differential amount as a difference from an amount assigned to each said injector which is detected and stored when all of said injectors are turned on and an amount when said injector is turned off; and
using said differential amounts assigned to each said injector as basis for creating a mean value and also for a correction.

9. The method according to claim 4 , wherein:
control of said number of injectors is corrected, in that an energizing duration for each of said number of injectors is adjusted.

10. The method according to claim 9 , wherein:
said energizing duration for each of said number of injectors is adjusted such that an energizing duration differential is added onto a current energizing duration, said energizing duration differential being calculated according to the following formula:
Δ BD[i ]=( MW −Δamount[ i ])* K , wherein:

ΔBD[i] signifies said energizing duration differential for an injector [i];
MW signifies a mean value calculated from differential amounts between amounts of a harmonic of the 0.5th order that are assigned to each of said number of injectors;
Δamount[i] is a determined differential amount for injector [i]; and
K is a constant;
said formula being used under condition ΣΔBD[i]=0.

Assignees

• Mtu Friedrichshafen Gmbh

Inventors

• Remele Jörg
• Toth Aron

Classifications

• F02D41/1486

  with correction for particular operating conditions · CPC title

• F02D2200/101

  Engine speed · CPC title

• F02D35/023

  by determining the cylinder pressure · CPC title

• F02D41/3094

  the fuel injection being effected by at least two different injectors, e.g. one in the intake manifold and one in the cylinder · CPC title

• F02D2250/18

  Control of the engine output torque · CPC title