CONTROL APPARATUS FOR HYBRID VEHICLE

摘要

The control apparatus of the present invention is applied to a hybrid vehicle that, as power sources for propulsion, includes an internal combustion engine that can change over between lean combustion and stoichiometric combustion, and motor-generators. The control apparatus performs the noise suppression control in which the operating points of the internal combustion engine are limited so as to suppress noise generated by a power transmission mechanism, and changes over the operational mode of the internal combustion engine if the thermal efficiency when performing the noise suppression control by changing over the operational mode of the internal combustion engine is higher than the thermal efficiency when performing the noise suppression control by keeping the operational mode of the internal combustion engine the same.

主权项

1. A control apparatus applied to a hybrid vehicle that comprises, as power sources for propulsion, an internal combustion engine that is capable of changing over to lean combustion and to stoichiometric combustion and an electric motor, and in which engine torque of the internal combustion engine and motor torque of the electric motor are outputted to a drive wheel via a power transmission mechanism that includes a gear group, comprising:
a combustion changeover device configured to change over an operational mode of the internal combustion engine between the lean combustion and the stoichiometric combustion by changing the air/fuel ratio of the internal combustion engine; a noise suppression control device configured to, during each of the lean combustion and the stoichiometric combustion, execute noise suppression control in which an operating point of the internal combustion engine as defined by engine rotational speed and engine torque is limited so that noise generated by the power transmission mechanism is suppressed; and a thermal efficiency calculation device configured to calculate a thermal efficiency of the internal combustion engine, both when the noise suppression control is being executed with the lean combustion, and also when the noise suppression control is being executed with the stoichiometric combustion; wherein the combustion changeover device changes over the operational mode of the internal combustion engine if the thermal efficiency calculated by the thermal efficiency calculation device will be higher if the noise suppression control is executed with the operational mode of the internal combustion engine being changed over, than if the noise suppression control is executed with the operational mode of the internal combustion engine being kept the same.