Method for controlling the operation of an engine system

An engine system of a vehicle, the engine system comprising and engine configured to operate in at least a two-stroke combustion mode and a four-stroke combustion mode, and an exhaust aftertreatment system (EATS) configured to reduce emissions from the engine exhausts, the EATS comprising a control unit configured to:

• determine predicted vehicle operational information comprising at least a predicted upcoming road event and a predicted engine operation associated with the upcoming road event,
• estimate or predict a temperature of the EATS;
• estimate or predict emissions out of the EATS, wherein the emissions out of the EATS are calculated emissions associated with the predicted engine operation;
• in response to the temperature of the EATS is below a predetermined temperature threshold, and that the emissions out of the EATS is above a predetermined emission threshold, instruct the engine system to perform a primary NOx emission reducing activity by operating the engine in a two-stroke combustion mode;
• subsequently to initiating the operation of the engine in a two-stroke combustion mode, and in response to the emissions out of the EATS is below the predetermined emission threshold, instructing the engine to change its engine operation from the two-stroke combustion mode to a four-stroke combustion mode.

A method for controlling the operation of an engine system in a vehicle, the engine system comprising an engine configured to operate in at least a two-stroke combustion mode and a four-stroke combustion mode, and an exhaust aftertreatment system, EATS configured to reduce emissions from the engine exhausts, the method comprising:

• estimating or predicting the temperature of the EATS;
• estimating or predicting the emissions out of the EATS;
• in response of that the temperature of the EATS is below a predetermined temperature threshold, and that the emissions out of the EATS is above a predetermined emission threshold, performing a primary NOx emission reducing activity by operating the engine in a two-stroke combustion mode, and deactivating at least one engine cylinder of the engine during the operation of the engine in a two-stroke combustion mode wherein the deactivated engine cylinder is controlled to perform engine compression brake, either as two-stroke or four stroke engine compression brake;
• subsequently to initiating the operation of the engine in a two-stroke combustion mode, and in response of that the emissions out of the EATS is below the predetermined emission threshold, changing engine operation from the two-stroke combustion mode to a four-stroke combustion mode.

An engine system of a vehicle, the engine system comprising and engine configured to operate in at least a two-stroke combustion mode and a four-stroke combustion mode, and an exhaust aftertreatment system, EATS configured to reduce emissions from the engine exhausts, the EATS comprising a control unit configured to:

• estimate or predict the temperature of the EATS;
• estimate or predict the emissions out of the EATS;
• in response of that the temperature of the EATS is below a predetermined temperature threshold, and that the emissions out of the EATS is above a predetermined emission threshold, instruct the engine system to perform a primary NOx emission reducing activity by operating the engine in a two-stroke combustion mode, and to deactivate at least one engine cylinder of the engine during the operation of the engine in a two-stroke combustion mode wherein the deactivated engine cylinder is controlled to perform engine compression brake, either as two-stroke or four stroke engine compression brake;
• subsequently to initiating the operation of the engine in a two-stroke combustion mode, and in response of that the emissions out of the EATS is below the predetermined emission threshold, instructing the engine to change its engine operation from the two-stroke combustion mode to a four-stroke combustion mode.