Design of a System Substituting Today’s Inherent Inertia in the European Continental Synchronous Area

Abstract

In alternating current (AC) power systems the power generated by power plants has to match the power drawn by consumers plus the system losses at any time. In the case of an imbalance between generation and consumption the frequency in the system deviates from its rated value. In order to avoid an unsuitable frequency, control power plants have to step in to level out this imbalance. Control power plants need time to adjust their power, which is why the inertial behaviour of today's AC systems is crucial for frequency control. In this paper it is discussed that the inertia in the European Continental Synchronous Area decreases due to the transition to renewable energy sources. This will become a problem for frequency control, which is why the provision of non-inherent inertia is proposed. This system consists of fast-responding energy storage. Its dimensions in terms of power and energy are determined. Since such non-inherent inertia requires investments a cost-efficient solution has to be found. Different technologies are compared in terms of the newly-introduced levelised cost of inertia. This paper concludes with the proposal that in future inertia should be traded and with the recommendation to use flywheels for this purpose, as these are the most cost-efficient solution for this task.

Virtual Inertia Control Application to Enhance Frequency Stability of Interconnected Power Systems with High Renewable Energy Penetration

“…Recently, considerable research has been proposed regarding virtual inertia control designs [5][6][7][8][9][10][11][12][13][14]. Reference [8] compared the dynamic characteristics of VSG and droop control methods to imitate inertia in the power system.…”

“…Reference [9] applied a droop control technique to perform synthetic inertia as an alternative inertia response in wind turbine systems for improving the dynamic stability. Reference [10] designed the control method to substitute today's inherent inertia in European power system. Reference [11] proposed the integration of DC microgrids as virtual synchronous machines into the power system/utility grid.…”

Virtual Inertia: Current Trends and Future Directions

“…Schemes to operate PV systems below their MPP with reserve for inertial response is also a possible option with the suitable market for such resources. A scheme to trade inertia is presented in [11]. Furthermore, the paper argues inertia should not be traded in terms of power or energy, but rather in terms of an inertia metric.…”

“…Similarly, the European Network of Transmission System Operators for Electricity (ENTSO-E) has reported increased frequency violations in the Nordic grid correlated with increased RES penetration [9]. As a consequence, inertial response from wind turbines is now mandatory in many countries [10,11] and the trend is extending towards PV plants as well. Accordingly, there is a strong practical relevance to research on virtual inertia systems which was of an academic nature in the past.…”

Impact of Distributed Generation Grid Code Requirements on Islanding Detection in LV Networks

“…Methodologies for the estimation of the energy storage system size to provide adequate inertia emulation, in addition to other stabilizing regulations, are presented in [39,40].…”