Hybrid electric vehicle quick start capability using integrated starter-generator

Three different strategies based on a theoretical model were used to simulate engine start process respectively, start in constant speed without compensation, start in constant speed with compensation, normal start. Predication results are presented here. Bench tests were also carried out, which are related to the three control strategies. It is found that the start in constant speed with compensation, which can make the engine start powerfully and smoothly, is better than the other two strategies. Using the speed and the torque control of the integrated starter-generator (ISG) at the engine start stage can reduce fuel consumption and emission.