A system and method for controlling the speed of a turbine engine, the turbine engine being operative to provide power to a primary load. When a decrease in the power requirement of the primary load is detected, at least a portion of the power generated by the turbine engine is redirected to a secondary load, thereby maintaining the speed of the turbine engine below a rated maximum speed. In the example of a turbine-powered train in which the turbine engine provides power to electric traction motors driving the wheels of the train, when a wheel spin is detected, at least a portion of the power generated by the turbine engine is diverted from the respective electric traction motor to rheostats for conversion to heat.