Method for determining modeling value of pressure in air supply portion of e.g. diesel engine of motor system, involves determining modeling value of pressure by resolving difference equation with determined current physical quantities

摘要

The method involves determining current physical quantities of an air mass current flowing into an air supply portion (4), temperature of air before a butterfly valve (8), a volumetric flow into an internal combustion engine (2), and a position of the butterfly valve. A difference equation is discretized, where the difference equation results with help of an ideal gas equation and a choke equation for modeling the butterfly valve. A modeling value of pressure is determined by resolving the difference equation with the help of the determined current physical quantities. Independent claims are also included for the following: (1) a device for determining a modeling value of pressure in an air supply portion of a motor system (2) a motor system comprising an air supply portion for supplying air (3) a computer program product having a set of instructions for executing a method for determining a modeling value of pressure in an air supply portion of a motor system.