Sensitivity Studies for AC Railway Networks Design
Résumé
AC Railway networks design is a particular application field which requires specific simulation tools. These networks include moving loads, different catenary types, and some connections between line conductors may exist, implying a specific research on line models. The results presented were obtained with a new simulation tool which was specifically build for railway networks design. This development was lead in parallel by CEGELY and SEMALY. This tool is composed of three modules: - Mechanical calculations. Speed, position and mechanical power vs. time are calculated, - Electrical calculations. Single or dual AT-feeding systems can be simulated. Contact wire to rail and rail to earth potential and currents in each conductor and at the pantograph of a train are calculated. Some other data such as power factor at the substation are also available. - Thermal calculations. The temperature of the contact wire is calculated. The work presented here deals with the electrical aspect and is divided into two parts. In the first part, three different line models are compared. The goal of this part is to quantify the error made on the calculated currents and voltages using one of the three models (Carson, Dubanton, Escane). In the second part, the influence of different parameters is studied in order to quantify the results sensitivity to input data variations. Parameters such as earth resistivity, rail to earth impedance value (along the line or at the substation) and rail to earth conductance are studied. These studies were made on the 1x25 KV single power supply system. A special attention is given to the rail to earth potential calculation, which must not exceed 50 Volts. This work has also been validated with dual power supply (2x25 Autotransformers system)