A new hybrid simulation integrating transient-state and steady-state models for the analysis of reversible DC traction power systems

Abstract

This paper presents a new hybrid simulation method for reversible traction power supply systems (RTPSSs) supplied by four-quadrant converters (4QC). RTPSSs overcome several drawbacks of conventional DC electrification systems, such as wasting of braking energy, output voltage fluctuation, and low power factor at light load conditions. The paper introduces the system topology of a RTPSS and illustrates its advantages over standard DC systems. A hybrid simulation method is proposed to study the performance of the RTPSS taking into account the dynamics of multiple trains. This hybrid simulation integrates train motion, steady-state and transient-state models, and is able to evaluate both the system-level steady-state performance (voltage, current, power and energy) and the equipment-level transient-state performance (harmonics, ripple, power factor and stability). Structure and signals flow of this hybrid simulation system have been introduced, and the methodology of modeling has been presented. The validity and applicability of the proposed hybrid simulation method have been proved by a case study of a 10 km railway line with 6 substations. To date, no other work has accomplished the steadystate and transient-state study using a single integrated simulation.

Non‐linear switched model for accurate voltage estimation and power flow analysis of DC railway systems

“…In such a case, on‐board ESS can offer off‐grid traction possibilities. More details about such technologies and other examples are in [5–16].…”

“…Nevertheless, simplifications leading to an equivalent catenary system for the two directions are often considered (Fig. 7 b ) [5–20]. This simplified model assumes that all the subsystems are supplied by a common catenary, thus reducing the number of nodes to consider.…”

“…[3, 4] and improving the infrastructure. Different solutions are, therefore, envisaged such as reversible traction power substations (TPSs) [5–8], energy storage systems (ESSs) [2, 8–16], or renewable energies [16]. Optimisation techniques are also often used to improve the operation of specific subsystems (i.e.…”

“…However, most simulation tools simplify this second phenomenon and only consider the increase in voltage due to the resistive part of the DCTN [19]. This problem is generally solved by considering reversible TPS or ESS [5–16], which contribute to improving receptivity. Other works aiming at estimating the energy consumption neglect this phenomenon because it occurs when all the TPSs are blocked, which do not lead to a significant error on global energy consumption [24].…”

Fuzzy Logic Optimization of Composite Brake Control Strategy for Load-Isolated Electric Bus

“…Regenerative braking, also known as braking energy recovery, is a new technology that is applied to new energy vehicles [1,2]. rough the regenerative braking technology, part of the kinetic energy of an electric vehicle can be converted into electric energy.…”