Energy of starting up to speed of DC train

In the last 20 ... 25 years the volume of recuperated electric energy is less than 2% of the consumed by traction, while it is possible to return about 10 ... 15%. The main reason is unsatisfactory and inefficient usage of recuperated and transmitted energy to the power supply system. The paper proposes to solve this problem and induce the efficiency and the degree of recuperated energy of DC multiple unit trains by the usage of on-board supercapacitive storage system. The methods of the electric traction theory and the theory of pulse electrical engineering are used for the problem solving. The developed methodology allows to calculate the energy, which is required to starting up the multiple unit train EPL2T to some speed 10 ... 80 km/h after its stopping. Furthermore, the capacity of the on-board storage is calculated in two cases of storing recuperated energy. The novelty of the paper is the new method for estimating energy, which is required to starting up (after the stopping) the train to a certain speed. The analytical expression of the capacity of the on-board storage system was achieved and calculated for the previously estimated energy. For the first time it was found that the energy, which was saved by the on-board supercapacitive storage system, is sufficient to start up the train to some speed and reach the characteristic of full field of the traction motors. The proposed autonomous mode of recuperative braking allows, at first, to increase significantly the efficiency of energy recovery, and secondly, to reduce the weight and size parameters of on-board storage supercapacitors.