DEVELOPMENT OF A MATHEMATICAL MODEL FOR DETERMINING TRACTION AND ENERGY PERFORMANCE INDICATORS OF A MANEUVERING LOCOMOTIVE

Abstract

Fuel consumption for traction significantly depends on the locomotive's operating mode, and by selecting a rational mode during station maneuvers or transit, it is possible to reduce fuel consumption. Previous works on this topic do not provide sufficient analysis of locomotive motion with varying numbers of connected engines. To optimize energy resource consumption, a combination of methods for the rational use of the locomotive is necessary. The traction and energy performance indicators for the maneuvering work of the ČME3 locomotive are calculated by performing traction calculations. In this paper, a mathematical model has been developed to determine these indicators when operating with 4 and 2 parallel-connected traction electric motors. Graphs were constructed to illustrate the relationship between traction force and locomotive speed, the time required to cover a given distance, fuel consumption for a specified distance, and the temperature rise above ambient conditions concerning 6 parallel-connected traction electric motors for the 3rd, 4th, and 5th positions of the engineer's controller. The locomotives were compared while covering the same stretch of track with the same train weight, considering wheel-rail adhesion constraints.Analyzing the obtained dependencies allows the conclusion that using different configurations of connected engines can result in fuel savings of up to 15 % during maneuvering operations, depending on operational conditions. Furthermore, the engine temperature remains within acceptable limits for insulation class F, based on the results of approximating existing locomotive characteristics and deriving analytical expressions (6, 7, 8, 24). Mathematical models of the motion of the ЧМЕ3 locomotive were created for various engine connection scenarios using the obtained mathematical formulas (9, 10, 11, 13, 20, 21, 22, 23, 24).