Experimental validation of a mathematical model for sizing end-of-production-line test benches for electric motors of electric vehicle

A mathematical model has been developed to optimize the design of an end-of-production-line (EOL) for testing and validating the performance and the functionality of newly manufactured electric motors/axles for electric vehicles. The model has been developed to predict the behaviour of EOL test benches and electric motors/axles under various boundary conditions, eliminating the need for extensive physical testing and reducing the corresponding power consumption. The proposed model can be applied to different electric motor/axle types and it is fully scalable in the case of different electric motor/axle power ratings. The maximum performance to be guaranteed by the electric machines (EMs) according to the car maker specifications are taken as inputs in the model. Then, the required performance of each main EOL test bench component is calculated and the corresponding products available in the market are selected based on manufacturers’ catalogues. In this study, an EOL test bench has been designed according to the proposed model outputs for testing a low-power (about 22 kW) electric axle. The performance of the designed EOL test bench have been measured and used to validate the proposed model and assess both the consistency of the constraints as well as the accuracy of predictions in terms of electric demands. The comparison between experimental and predicted data exhibited a reasonable agreement, allowing to demonstrate that, despite some discrepancies, the model gives an accurate representation of the EOL test benches performance.