Abstract
Engine, hydraulic converter and mechanical transmission are regarded as a whole system, a set of evaluation indexes for optimal matching of the powertrain of hydraulic drive vehicle is studied and put forward in this paper: the loss rate of driving power of vehicle is used as an evaluation index of the extent to which dynamic performance of vehicle develops, the loss rate for effective efficiency of engine is used as an evaluation index of the extent to which fuel economy of vehicle develops. A new optimum model for the transmission parameters of hydraulic drive vehicle is presented. An optimum example of the transmission parameters of 160 t all-road crane truck is given in this paper. .