What is the Right Way to Model Traction Power Distribution in Complex Heavy Haul Locomotive Models?

Abstract

The modeling of a heavy haul locomotive is a quite challenging task because it requires introducing multidisciplinary knowledge in the final model design. Common methods of modeling heavy haul locomotives are well described in recent publications. However, design and modeling approaches for both bogie traction control and independent wheelset traction control design architectures should not be applied for a situation when the locomotive is not limited by adhesion. In both those approaches the traction power is equally distributed between two traction inverters in the case of bogie traction control design architecture or between six traction inverters in the case of independent wheelset traction control design architecture. This means that an unreasonable limitation of traction power exists in those modeling approaches. To resolve this issue, the right way to model the traction power system is to introduce a supplementary control mechanism that adjusts the torque reference at each inverter of the locomotive based on a physical state estimation of the traction power condition of the locomotive during each time step of a simulation process. This paper discusses the right ways of modeling this scenario and how the proposed improvement affects the traction performance in locomotive adhesion studies.