Method for Operating a Spark Ignition Internal Combustion Engine with an Exhaust Gas Turbocharger

摘要

A method is provided for operating a spark ignition internal combustion engine with an ignition angle adjustment by a control unit and with an exhaust gas turbocharger with a turbine and a compressor and, wherein a throttle valve is provided in an intake air manifold between the compressor and the internal combustion engine. A compressed air device is provided for introducing compressed air into the intake air manifold, including at least one pressure tank and an air injection valve that can be opened by the control unit and is connected to provide gas to the pressure tank for introducing compressed air into the intake air manifold between the throttle valve and the internal combustion engine. A first gas pressure is measured in the intake air manifold between the compressor and the throttle butterfly and a second gas pressure is measured between the throttle valve and the internal combustion engine. The throttle valve can be controlled or regulated by the control unit.

主权项

1. A method for operating a spark ignition internal-combustion engine with an ignition angle adjustment via an electronic control unit and having an exhaust gas turbocharger with a turbine, arranged in an exhaust gas section for an exhaust gas of the internal-combustion engine, and a compressor, arranged in an intake air section for intake air for the internal-combustion engine, a throttle valve being provided in a flow direction of the intake air downstream of the compressor and upstream of the internal-combustion engine, as well as having a compressed-air injection device including at least one pressure tank and an air injection valve connected in a gas-carrying manner with the pressure tank and being openable and closable by the electronic control unit, for introducing compressed air into the intake air section between the throttle valve and the internal-combustion engine, wherein, within the intake air section, a first gas pressure p1 between the compressor and the throttle valve and a second gas pressure p2 between the throttle valve and the internal-combustion engine are measured, the throttle valve being controllable or automatically controllable by the control unit, the method comprising the acts of:
a) increasing a torque demand on the internal-combustion engine; b) opening the air injection valve and constantly measuring the first and second gas pressure p1, p2 by the electronic control unit; c) closing the throttle valve by the electronic control unit at the earliest with the opening of the air injection valve or as soon as the second pressure p2 exceeds the first pressure p1; d) calculating a first gas mass flow, which is delivered into the internal-combustion engine, and calculating a second gas mass flow, which corresponds to the increased torque, by the electronic control unit; e) as soon as the first gas mass flow is greater than the second gas mass flow, displacing an ignition angle to late; f) as soon as the first gas mass flow multiplied by a factor ezw,min is equal to the second gas mass flow, slowly closing the air injection valve; g) as soon as the exhaust gas turbocharger reaches a defined rotational speed, completely closing the air injection valve; h) as soon as the first gas pressure p1 equals the second gas pressure p2, opening of the throttle valve by the control unit; and i) conventionally operating the internal-combustion engine, whereby a reaction time to a increased torque of the internal-combustion engine is minimized, while the compressed-air consumption is minimal.