Contribution of the thermal inertia of trains to the primary frequency control of electric power systems

Use of the Thermal Inertia of Trains for Contributing to Primary Frequency Control and Inertia of Electric Power Systems

“…Similarly, railway systems, depending on the traction technology and the electrification configuration, can be modeled with different approaches [17], [18], [19], [20], [21], [22], [23], which will depend on the nature of the study (dynamic, mechanical, electrical, electronical, etc.). In this work, the same modeling approach the authors presented in [9] is used (Fig. 1).…”

“…These studies are aimed at evaluating the thermal comfort and/or the thermodynamics of trains, internally and externally. According to the scope of this work, the model in [9] is used, which uses some approximations made in [31]. Equations ( 7) and ( 8) are used to represent the thermodynamics of trains by a second order system with one-dimensional heat flow.…”

“…In a previous work [9], the authors reviewed some of the recent trends in frequency control based on demand management. In addition, the participation of railways in primary frequency control tasks is studied, based on the variation of the power consumption of the air conditioning system of trains, without affecting the thermal comfort of passengers.…”

“…However, it is significant the little amount of research related to how the railway sector could provide inertia to electrical power systems. In [9], the authors observed the absence of studies on the contribution to primary frequency control. For the present work, only two papers related to virtual inertia provision were found: Hao and Chen [14] proposed an improved algorithm for the emulation of inertia by a bidirectional converter in the catenary of a direct current railway, in which voltage fluctuations were reduced by means of a virtual capacitor; and Yu et al [15] proposed a novel control, based on virtual inertia, to mitigate lowfrequency oscillations usually present in high-speed AC railways, where a virtual capacitor is also emulated to mitigate voltage fluctuations in the DC link on board the train, which also reduces low-frequency oscillations in the catenary.…”

Survey of Real-World Grid Incidents–Opportunities, Arising Challenges and Lessons Learned for the Future Converter Dominated Power System

“…inertia, damping and short-circuit current, such desired behavior must be enforced by control and automation design, thus putting a new importance on this domain. This is reflected in recent developments in the field of grid service provision tailored to grids with high ratios of renewable generation, such as virtual inertia [13]- [16], fast frequency response (FFR) [17], [18] or voltage regulation [19]. Moreover, the topology of the power grid is severely altered, the number and diversity of grid participants is vastly increased and well understood devices are being substituted.…”