Characterization of the Overall Power Train on Driving Cycles

5 Characterization of the Overall Power Train on Driving Cycles 

The aim of the experimental tests performed on the overall power train is the evaluation of efficiency and the individuation of the basic energy management strategies necessary to assure proper vehicle operation. The experimental investigation is performed in dynamic conditions on two different urban driving cycles, the R47 and R40, considered by the European regulations on vehicle emission control. In Fig. 6.21a and b, the two cycles are reported in terms of motor speed versus time. 

In particular. the R47 cycle (Fig. 6.21a) is imposed by European legislation for exhaust emission measurements of mopeds powered by internal combustion engine, and here is used in absence of specific legislation regarding electrical mopeds. The R47 cycle requires the maximum power in the initial phase up to the maximum speed (6000 rpm), then a period of constant speed of 50 s at maximum speed, a fast deceleration up to 2400 rpm, a second period of constant speed, a final deceleration up to zero speed. The R40 cycle (Fig. 6.21b) comprises three phases, the first two characterized by acceleration, constant speed (1500 and 3200 rpm) and deceleration steps, while the last one presents two steps at constant speed (5000 and 3500 rpm), before returning to zero speed. 

The R40 cycle is required by the European legislation to evaluate the exhaust emissions of motorcycles and, after addition of a fourth phase at higher speed, also for passenger cars. It is used in this chapter to evaluate the performance of the fuel cell power train on a typical urban route, not strictly associated with the driving way assumed for a moped. The acceleration phases of the two cycles correspond to stack power increase rates of 100 W/s for R40 and 500 W/s for R47. 

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