Engine management
2 Assignments
0 Petitions
Accused Products
Abstract
An in-cylinder pressure sensor obtains a high resolution pressure curve for each cylinder cycle allowing the various data to be derived for improved monitoring and control of operation of the engine. A more accurate measure of work done by the engine is obtained allowing more accurate estimation of the vehicle torque and hence real torque control. In addition engine losses can be more accurately calculated and the estimates corrected yet further by obtaining an accurate top dead centre position for the engine cylinders.
66 Citations
54 Claims
-
1-29. -29. (canceled)
-
30. A method of deriving vehicle torque comprising;
-
measuring cylinder pressure during a cylinder cycle;
constructing a pressure variation function;
obtaining work done by the engine therefrom and deriving vehicle torque from the work done. - View Dependent Claims (31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42)
-
- 43. A method of deriving engine cylinder top dead centre comprising measuring cylinder pressure during a cylinder cycle, constructing a pressure variation function and deriving top dead centre therefrom.
- 49. A method of obtaining the indicated mean effective pressure IMEP for a vehicle engine cylinder comprising measuring the cylinder pressure during a cylinder cycle, obtaining corresponding values of cylinder volume during the cycle, deriving top dead centre during the cycle, correcting the volume values based on the derived value of top dead centre, and integrating pressure against volume to obtain the IMEP.
-
54. A method of diagnosing engine conditions in an engine with two or more cylinders comprising the steps of skip firing individual cylinders, deriving a measure of engine friction loss and comparing the derived loss to diagnose a respective cylinder condition.
Specification