Starting control apparatus for internal combustion engine

Abstract

When a first motor MG cranks and starts an engine that is in the cold, the revolving speed of the engine does not increase quickly . It is accordingly required to control the first motor MG , in order to prevent electric power stored in a battery from being wasted. A starting control apparatus does not cause the first motor MG to output a torque corresponding to a difference between a target revolving speed N* and an actual revolving speed Ne of the engine , but gradually increases a target torque STG by the open-loop control and restricts the magnitude of the target torque STG to a preset maximum torque STGMAX, which depends upon a cooling water temperature Tw of the engine . When the engine is in the cold, the high viscosity of lubricant causes the revolving speed of the engine not to quickly increase in response to the high target torque set to the first motor MG . In this case, the maximum of the target torque is restricted to a smaller value, so as to prevent the electric power stored in the battery from being wasted. The injection allowable revolving speed, at which the fuel injection to the engine is allowed to start, is also set equal to a small value. This causes the engine to start self driving at an earlier timing, thereby saving the electric power consumed by the first motor MG