A simulation model of traction power supply system to determine energy indicators in conditions of energy storage system operation
The article deals with the issues of simulation of the operation of DC traction power supply systems with the use of power storage systems. The development of simulation modeling allows us to study the influence of one or several factors on the performance of the traction power supply system. These factors include weight, technical speed, axle load, regenerative braking, features of the schedule for cargo traffic, etc. Modeling allows one to assess the degree of influence of one or a group of factors on performance indicators such as: current collector voltage, load capacity of power equipment, heating temperature of wires and cables, traction power consumption, energy recovery volume, technical losses, etc. Currently, simulation allows performing a series of calculations to obtain a statistical assessment of the influence of factors on indicators (of performance of the traction power supply system) and also an analytical representation of the obtained dependencies necessary for solving the problems of analysis and forecasting changes in the performance indicators of the traction power supply system. The article presents diagrams of multivariate calculations performed to assess the impact of infrastructure parameters, rolling stock and traffic organization on the performance of traction power supply systems. The addition of equivalent circuits currently used for calculations of traction power supply systems makes it possible to perform most calculations to assess the impact of performance of electric power storage systems on energy indicators and assess their operating conditions. The peculiarity of calculation of the equivalent circuits for traction power supply systems containing electricity storage devices using known methods, in particular, the method of nodal potentials, is the need to take into account their on and off state, determined by power and energy consumption restrictions, the voltage level in the contact overhead system. It is proposed to supplement the existing calculation methods with a calculation algorithm that takes into account the operating conditions of the storage system. The calculation method allows us to evaluate the operating conditions of storage systems with electric traction load, the requirements for their main parameters and the impact on the performance of the traction power supply system.