Evaluation of performance and efficiency and type approval of an electrically assisted bicycle drive

The diffusion of electrically assisted bicycles gives rise to the need of the evaluation of the performance and efficiency of the electric drive that supply it. In this paper, is presented a test bench for the estimation of the electric drive output torque under several speed and load conditions. Moreover, the test bench detects the electrical and mechanical parameters that allow to evaluate the electrical drive efficiencies. The test bench has been designed in agreement with the Directive 2002/24/EC of the European Parliament since it detects the maximum continuous rated power (that must be lower than 0.25 kW) and evaluates if the output is progressively reduced and finally cut off as the vehicle reaches a speed of 25 km/h, or sooner, if the cyclist stops pedaling. The test bench has been conceived also with the aim of releasing type-approval certification. With the test bench, an electric rickshaw prototype available in the University of Palermo SDES Laboratory has been tested. Test results are here presented and discussed.