MODELING OF ELECTRICAL POWER STABILIZATION IN TRAIN TRACTION AND CONTROL

Abstract

The productivity of the Standard Gauge Railway (SGR)-Project Lot I project can be increased by increasing the efficiency of the traction power supply of 2 x 27.5 kV AC from the grid supply for train traction and railway systems. The main elements of traction power supply for railway systems are traction power substations (TPS), overhead contact systems (category systems), electric-electric locomotives, auto-transformer substations (ATS), and double autotransformer substations (DATS). The main focus of this thesis is the study of the modelling of electrical power stabilization in train traction and control. Firstly, I have designed the power flow scheme of the traction power supply without OLTC of a single phase two-winding traction power transformer (TWCTTPT) 20 MVA, 220kV/2x27.5 kV AC, positive feeder, negative feeder, neutral, auxiliary transformer (27.5 kV/230 V AC for LV supply), and electric multiple units by using the MATLABSimulink software with simulation results. Secondly, I have designed the rectifier circuit, a single- to three-phase IGBT/diode inverter, for driving traction motors with simulation results. Thirdly, I have designed the modelling of an OLTC incorporating LDC by using proposed formulas to make up a mathematical analysis of the voltage stabilization of feeders (2 x 27.5 kV AC). Fourthly, I have designed the power flow analysis of OLTC/voltage regulation of a single-phase TWCTTPT incorporating LDC using ETAP software. Finally, I have designed the modelling of ATS and DATS with their simulations for analyzing voltage stabilization with simulation results. The thesis study will be conducted successfully by modelling electrical power stabilization methods according to the analysis of collected technical data from the site for the entire traction power supply scheme and important components of the electric-electric locomotive, including step-down transformers, rectifier circuits, single- to three-phase IGBT/diode inverters, and three-phase traction motors for driving traction loads with better efficiency for the case study of the Standard Gauge Railway (SGR) Lot I project from Dar es Salaam city to Morogoro region in Tanzania.