Locomotive control system having thermal management

A method of operating a machine having an engine, a first alternator, a second alternator, and an aftertreatment system, the method comprising:

• directing exhaust away from the engine through the aftertreatment system;
• determining a temperature of the exhaust;
• determining an available power output of the first alternator;
• determining an engine load increase needed to raise the temperature of the exhaust to an operating temperature of the aftertreatment system;
• selectively connecting the first alternator to a power consumer to achieve the engine load increase when the available power output of the first alternator is greater than the engine load increase;
• and
• selectively connecting the second alternator to the power consumer to achieve the engine load increase when the available power output of the first alternator is less than the engine load increase.

A locomotive, comprising:

• an engine;
• a first alternator driven by the engine;
• a second alternator driven by the engine;
• an aftertreatment system connected to receive exhaust from the engine;
• a sensor associated with the aftertreatment system and configured to determine a temperature of exhaust passing through the aftertreatment system;
• a throttle selector movable from an idle position through a range to a maximum position to affect a speed of the engine;
• one or more power consumers connectable to at least one of the first and second alternators;
• an auxiliary power source connectable to the one or more power consumers;
• and
• a controller in communication with the sensor and connectable to the first and second alternators, the controller being configured to:
• determine an available power output of the first alternator;
• determine an available power output of the second alternator;
• determine a load increase of the engine needed to raise the temperature of the exhaust to a threshold temperature;
• selectively connect the first alternator to at least one of the one or more power consumers to achieve the load increase when the available power output of the first alternator is greater than the load increase;
• and
• selectively connect the second alternator to the at least one of the one or more power consumers to achieve the load increase when the available power output of the first alternator is less than the load increase and the available power output of the second alternator is greater than the load increase;
• track a time elapsed when the throttle selector is moved to the idle position;
• determine a load generated by one or more power consumers;
• and
• selectively shut down the engine and activate the auxiliary power source only when the load generated by the one or more power consumers is less than an output capacity of the auxiliary power source and the temperature of the exhaust passing through the aftertreatment system is below a threshold temperature for limiting a temperature the aftertreatment system.