Abstract: A method and system to control engine shutdown in a hybrid electric vehicle (HEV) are provided. Tailpipe emissions are reduced during the many engine shutdowns and subsequent restarts during the course of an HEV drive cycle, and evaporative emissions are reduced during an HEV “soak” (inactive) period. The engine shutdown routine can ramp off fuel injectors, control engine torque (via electronic throttle control), control engine speed, stop spark delivery by disabling the ignition system, stop purge vapor flow by closing a vapor management valve (VMV), stop exhaust gas recirculation (EGR) flow by closing an EGR valve, and flush the intake manifold of residual fuel (vapor and puddles) into the combustion chamber to be combusted. The resulting exhaust gas byproducts are then converted in the catalytic converter.

Abstract: A hybrid electric vehicle 10 and a method for operating the hybrid electric vehicle 10 is provided. Combustion is made to occur within the internal combustion engine 24 only after the crankshaft 25 of the engine 24 has been rotated by an electric motor or generator 30 to a certain speed and according to a certain ramped or partially ramped profile 114, 112, thereby reducing the amount of emissions from the engine 24, allowing for a more efficient torque transfer to wheels 42, and allowing for a smoother operation of the vehicle 10. The fuel injectors 13, throttle plate 11, and spark plugs 15 are also controlled in order to allow emissions to be reduced during activation of the engine and to allow the catalytic converter 7 to be heated in order to allow these emissions to be further reduced as the engine 24 is operating.

Abstract: A method of operating a hybrid electric vehicle 10 to reduce emissions. The method utilizes the vehicle's electric motor/generator 12 to generate a negative torque during cold-start conditions, effective to increase the load on the internal combustion engine 16, thereby reducing the light-off time of the catalytic converter 28. The method also reduces emissions by utilizing the vehicle's motor/generator 12 to provide a supplemental torque to engine 16 during transient events, thereby reducing the generated mass flow and amount of untreated emissions.

Abstract: A method and system to control engine shutdown for a hybrid electric vehicle (HEV) is provided. Tailpipe emissions are reduced during the many engine shutdowns and subsequent restarts during the course of an HEV drive cycle, and evaporative emissions are reduced during an HEV “soak” (inactive) period. The engine shutdown routine can ramp off fuel injectors, control engine torque (via electronic throttle control), control engine speed, stop spark delivery by disabling the ignition system, stop purge vapor flow by closing a vapor management valve (VMV), stop exhaust gas recirculation (EGR) flow by closing an EGR valve, and flush the intake manifold of residual fuel (vapor and puddles) into the combustion chamber to be combusted chamber to be combusted. The resulting exhaust gas byproducts are then converted in the catalytic converter.

Abstract: A hybrid electric vehicle 10 and a method for operating the hybrid electric vehicle 10 is provided. Combustion is made to occur within the internal combustion engine 24 only after the crankshaft 25 of the engine 24 has been rotated by an electric motor or generator 30 to a certain speed and according to a certain ramped or partially ramped profile 114, 112, thereby reducing the amount of emissions from the engine 24, allowing for a more efficient torque transfer to wheels 42, and allowing for a smoother operation of the vehicle 10. The fuel injectors 13, throttle plate 11, and spark plugs 15 are also controlled in order to allow emissions to be reduced during activation of the engine and to allow the catalytic converter 7 to be heated in order to allow these emissions to be further reduced as the engine 24 is operating.

Abstract: A method of operating a hybrid electric vehicle 10 to reduce emissions. The method utilizes the vehicle's electric motor/generator 12 to generate a negative torque during cold-start conditions, effective to increase the load on the internal combustion engine 16, thereby reducing the light-off time of the catalytic converter 28. The method also reduces emissions by utilizing the vehicle's motor/generator 12 to provide a supplemental torque to engine 16 during transient events, thereby reducing the generated mass flow and amount of untreated emissions.

Abstract: A hybrid electric vehicle 10 and a method for operating the hybrid electric vehicle 10 in which combustion is made to occur within the internal combustion engine 24 only after the crankshaft 25 of the engine 24 has been rotated by an electric motor or generator 30 to a certain speed and according to a certain ramped or partially ramped profile 114, 112, thereby reducing the amount of emissions from the engine 24, allowing for a more efficient torque transfer to wheels 42, and allowing for a more smoother operation of the vehicle 10. The fuel injectors 13, throttle plate 11, and spark plugs 15 are also controlled in order to allow emissions to be reduced during activation of the engine and to allow the catalytic converter 7 to be heated in order to allow these emissions to be further reduced as the engine 24 is operating.

Abstract: A method of operating a hybrid electric vehicle 10 to reduce emissions. The method utilizes the vehicle's electric motor/generator 12 to generate a negative torque during cold-start conditions, effective to increase the load on the internal combustion engine 16, thereby reducing the light-off time of the catalytic converter 28. The method also reduces emissions by utilizing the vehicle's motor/generator 12 to provide a supplemental torque to engine 16 during transient events, thereby reducing the generated mass flow and amount of untreated emissions.

Abstract: This invention relates to a hybrid electric vehicle component coolant control system and method. The coolant system has an electric pump to move coolant through a closed system including engine and motor components. Such components to be cooled can include any electric motors, power electronics, engine, and transmission. The preferred embodiment controls coolant flow to the vehicle engine and motor in a single closed loop. Vehicle components have temperature sensors that send temperature signals to an electric coolant pump duty cycle control strategy. The control strategy makes a determination of a duty cycle of the electric coolant pump as a function of the temperatures of vehicle components and orders the duty cycle of the electric pump. In the preferred configuration, engine temperature sensors can acquire either engine coolant temperature or engine cylinder head temperature.

Abstract: A method of controlling an engine 12 during engine shutdown to reduce evaporative emissions is provided. The method includes a step 50 of shutting off a fuel pump 28 of the engine 12. The method also includes a step 52 of burning off the fuel from a fuel rail 24 in a cylinder 18 of the engine 12 after the fuel pump 28 is shut off. During the burning off of the fuel, a duty cycle of each fuel injector 22of engine 12 is controlled to allow the engine 12 to operate generally cyclically about a predetermined air/fuel ratio. The predetermined air/fuel ratio is preferably stoichiometric. By burning off the fuel in the fuel rail 24 after the fuel pump 28 is shut off, the fuel pressure in the fuel rail 24 is reduced. The reduced fuel pressure in the fuel rail 24results in reduced evaporative emissions from the engine 12.

Abstract: A hybrid electric vehicle 10 and a method for operating the hybrid electric vehicle 10 in which combustion is made to occur within the internal combustion engine 24 only after the crankshaft 25 of the engine 24 has been rotated by an electric motor or generator 30 to a certain speed and according to a certain ramped or partially ramped profile 114, 112, thereby reducing the amount of emissions from the engine 24, allowing for a more efficient torque transfer to wheels 42, and allowing for a more smoother operation of the vehicle 10. The fuel injectors 13, throttle plate 11, and spark plugs 15 are also controlled in order to allow emissions to be reduced during activation of the engine and to allow the catalytic converter 7 to be heated in order to allow these emissions to be further reduced as the engine 24 is operating.

Abstract: This invention is a method and system to control engine shutdown for a hybrid electric vehicle (HEV). The invention allows for reduced tailpipe emissions during the many engine shutdowns and subsequent restarts during the course of an HEV drive cycle and reduced evaporative emissions during an HEV “soak” (inactive) period. The engine shutdown routine can ramp off fuel injectors, control engine torque (via electronic throttle control), control engine speed, stop spark delivery by disabling the ignition system, stop purge vapor flow by closing a vapor management valve (VMV), stop exhaust gas recirculation (EGR) flow by closing an EGR valve, and flush the intake manifold of residual fuel (vapor and puddles) into the combustion chamber to be combusted. The resulting exhaust gas byproducts are then converted in the catalytic converter.

Abstract: This invention is a method and system to control engine shutdown in a hybrid electric vehicle (HEV). The invention allows for reduced tailpipe emissions during the many engine shutdowns and subsequent restarts during the course of an HEV drive cycle and reduced evaporative emissions during an HEV “soak” (inactive) period. The engine shutdown routine can ramp off fuel injectors, control engine torque (via electronic throttle control), control engine speed, stop spark delivery by disabling the ignition system, stop purge vapor flow by closing a vapor management valve (VMV), stop exhaust gas recirculation (EGR) flow by closing an EGR valve, and flush the intake manifold of residual fuel (vapor and puddles) into the combustion chamber to be combusted. The resulting exhaust gas byproducts are then converted in the catalytic converter.

Abstract: Periodic shutdown of the internal combustion engine (12) during operation of a hybrid electric vehicle (HEV) is achieved by shutdown of a vapor management valve (VMV) of the engine evaporative emission control system and an EGR valve (150) of the tailpipe emission control system at the time an engine shutdown command is provided to a controlled engine shutdown routine that, after closing of the VMV and EGR valves, then commands disabling of the engine fuel injectors (160) in a manner to stop engine operation.