Control strategy for plug-in hybrid electric vehicle

摘要

A control method is provided for controlling a plug-in hybrid vehicle including an engine (12 see fig 1), a catalytic converter (38 see fig 1 and an electric propulsion system comprising an integrated motor generator (CIMG 10 see fig 1). The method comprises a step 68 of monitoring a state of charge SOC of a battery (22 see fig 1) when in a charge depletion mode and determining 70 a rate of depletion of the SOC. The duration of a depletion period until reaching a minimum SOC is estimated 72. A warming period of the catalytic converter is determined 78 and compared 80 with the depletion period. The engine (12) is activated 82 if the depletion period is less than or equal to the warming period. The invention is aimed at addressing potential issues with emissions when it can be anticipated that the engine will have to restart.