Aftertreatment heat up strategies in vehicles with hybrid powertrains

A control system comprising a processor and memory, the memory storing instructions that when executed by the processor, direct the control system to:

• detect a temperature of a selective catalytic reduction (SCR) device of an aftertreatment system of a vehicle with a hybrid powertrain comprising an electrical drivetrain and an internal combustion engine;
• determine whether or not the detected temperature is within an effective temperature range for the SCR device, wherein a cold start is identified when the detected temperature is determined to be below the effective temperature range;
• and
• operate in the cold start by:
• directing the electrical drivetrain to fulfil a vehicle drive load of the vehicle;
• and
• while directing the electrical drivetrain to fulfil the vehicle drive load,
• operating the internal combustion engine in idle to spin the internal combustion engine to generate airflow for transport of heat through an aftertreatment system;
• and
• after initiating operation of the internal combustion engine, directing an electric heater to raise a temperature for the heat transported by the airflow from the internal combustion engine through a selective catalytic reduction (SCR) device of the aftertreatment system,
• wherein all cylinders of the internal combustion engine are fueled while the electrical drivetrain is fulfilling the vehicle drive load and the internal combustion engine is operating to generate airflow to transport the heat, including by the temperature of the electric heater into the aftertreatment system.