A method of reducing cold start emissions in a series mode hybrid electric vehicle, including an internal combustion engine with an exhaust duct having a catalyst and a downstream oxygen sensor, an output of the combustion engine being connected to an electric generator with a power output of at least 10 kW that is connected to an electric motor which is coupled to a drive shaft of two or more wheels. The method includes detecting a cold start condition, injecting fuel into the engine such that combustion at a lambda value, λ, is achieved for which λ>1, running the engine at a speed of 1000 rpm or higher, determining if the efficiency of the catalyst reaches a first level, setting λ to about 1 after the predetermined efficiency level of the catalyst has been reached, and reducing the speed to working conditions when the catalyst efficiency reaches a second level.

A method of providing a heating cycle for an after-treatment system is described. The method comprises initiating a pre-charge cycle of a DCDC converter and determining a temperature of the after-treatment system. In response to determining the temperature of the after-treatment system is below a threshold temperature and the pre-charge is complete, the method further comprises operating a solid-state switch to electrically connect a high voltage power source to a heating element to of the after-treatment system, and heating the after-treatment system with the heating element until the after-treatment system reaches the threshold temperature.

An apparatus of starting an engine for a hybrid vehicle may include an engine configured for generating power by combustion of a fuel; a starting motor configured for starting the engine; a hybrid starter-generator configured for starting the engine, selectively operating as a generator, and selectively operating as a torque auxiliary device of a drive motor; and a controller configured for selectively performing a first starting mode to start the engine using the hybrid starter-generator according to a coolant temperature, a second starting mode to start the engine using the starting motor, and a third starting mode to start the engine using the starting motor and the hybrid starter-generator according to the coolant temperature.

A hybrid power train structure for off-road vehicles (ATVs, UTVs and SSVs) uses an internal combustion engine (“ICE”) rotating a crankshaft through a continuously variable transmission (“CVT”) as a primary source of locomotion torque, but also includes a driving/generator motor which, in certain established conditions, can either provide an additional or alternative source of locomotion torque or can harvest electricity from the torque created by the internal combustion engine. The driving/generator motor is an axial flux motor of small size for its relative torque output, which can either be directly coupled to the CVT output shaft or, when additionally used as a starter motor for the ICE in an automatic ICE starting and stopping routine.

Aspects of the present invention relate to a method and to a control system for controlling an engine and an electric traction motor of a vehicle, the control system comprising one or more controllers, wherein the control system is configured to: receive an indication of engine speed during engine idling; and control the electric traction motor to reduce a difference between the engine speed and an engine idle speed target

An embodiment method for controlling a hybrid vehicle includes driving a motor that starts an engine of the hybrid vehicle and controlling the motor to generate an engine starting torque to prevent a vibration of the engine, wherein the engine starting torque is generated by a feedforward control method. An embodiment device for controlling a hybrid vehicle includes a motor configured to start an engine of the hybrid vehicle, and a controller configured to drive the motor and control the motor to generate an engine starting torque to prevent a vibration of the engine, wherein the engine starting torque is generated by a feedforward control method.

A military vehicle including an engine coupled to the chassis for providing mechanical power to the military vehicle, a motor/generator coupled to the engine, and an energy storage system including a battery electrically coupled to the motor/generator. The military vehicle is operable in a silent mobility mode with the engine inactive and the energy storage system providing power to the motor/generator to operate the military vehicle. The motor/generator and the battery are sized such that electrical power generation through engine drive of the motor/generator is greater than the power depletion through operation of the military vehicle in the silent mobility mode. The motor/generator can charge the energy storage system while the military vehicle is driving or stationary.

A hybrid drive system has two sources of driving power: a non-combustion drive system to provide mechanical torque and rotation to a driveshaft, and an opposed-piston, internal combustion engine configured to provide energy for the non-combustion drive system.

A method and system for operating a hybrid vehicle that includes an integrated starter/generator and a driveline disconnect clutch is described. In one example, the method determines whether or not to rotate an engine via an electric machine while propelling a vehicle via the electric machine according to vehicle efficiency.

When a vehicle is in a traveling state having a low necessity to quickly increase required traveling torque, high-rotational-speed engine starting unit that reduces an emission amount of particulate matter emitted during engine starting starts the engine. Since quick torque response is not required when the vehicle is in the traveling state having the low necessity to quickly increase the required traveling torque, the high-rotational-speed engine starting unit starts the engine, so that increase of the emission amount of particulate matter emitted during engine starting can be curbed.