A bench test of a hybrid engine with auxiliary power unit(APU) dynamic coordinated control strategy was carried out during the mode transition phase

and the dynamic characteristics of the engine during the transition phase

such as starting and variable speed and load were analyzed. The dynamic coordinated control strategy based on a torque model was designed to ensure that the engine runs along the optimal fuel consumption curve during the transition time in order to achieve the advantage of short transition time and low speed and torque overshoot. Results show that by increasing the engine idle speed

the warm-up process can be accelerated without causing the engine to start too slowly. Moreover

in the early stage of engine start-up

a proper fuel injection can achieve low fuel consumption without affecting engine starting performance.