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or provide power directly to the electric motors depending on vehicle’s mode. A planetary gear is used in order to split power among the engine, the generator and the differential. The nominal voltage of the battery pack is 201.6 V comprising 168 nickel-metal hydride (NiMh) cells, and its nominal capacity is 6.5 Ah. The battery pack voltage is raised by a boost converter leading to a 400 V dc-link voltage. Finally, each in-wheel motor is fed through a three-phase inverter (Figure 3) and is individually controlled using vector control method. For the assess- ment of the overall system performance, a HEV model, which is available in Matlab/Simulink version R2016a (Figure 4) has been modified properly in order to meet the specific problem requirements. This model permits the study of vehicle’s dynamic behaviour, as the aerody- namical and frictional phenomena are included. The vehicle’s and its component specifica- tions of the case study are presented in Table 1. Figure 4. Matlab/Simulink HEV’s model. Figure 3. Typical in-wheel motors drive topology. Hybrid Electric Vehicles134