Power Hardware-in-the-Loop Test of a Low-Cost Synthetic Inertia Controller for Battery Energy Storage System

Abstract

In the last years, the overall system inertia is decreasing due to the growing amount of energy resources connected to the grid by means of power inverters. As a consequence, reduced levels of inertia can affect the power system stability since slight variations of power generation or load may cause wider frequency deviations and higher rate of change of frequency (RoCoF) values. To mitigate this trouble, end-user distributed energy resources (DERs) interfaced through grid-following inverters, if opportunely controlled, can provide additional inertia. This paper investigated the possibility of improving the control law implemented by a low-cost controller on remotely controllable legacy DERs to provide synthetic inertia (SI) contributions. With this aim, power hardware-in-the-loop simulations were carried out to test the capability of the proposed controller to autonomously measure frequency and RoCoF and provide SI actions by controlling an actual battery energy storage system.

Fast Frequency Support Through LED Street Lighting in Small Non-Synchronous Power Systems

“…Large geographical areas are therefore theoretically reachable by the same control system, although the easiest solution could be implementing local frequency measure and control at each lighting control box that usually manages few dozens of street lamps. An example of low-cost synthetic inertia local controller has been studied by the authors in [16].…”

“…A few papers investigated the possibility to provide SI or FFR by means of domestic thermal loads as refrigerators/boilers [12], [13] and variable speed heat pumps [14]. Other studies focused on providing such grid services through the advanced control of single phase electric vehicles [15] and Battery Energy Storage System (BESS) [16], [17], [18]. In [19], the fast primary frequency regulation of a dual-BESS scheme was investigated considering also the coordination with the ramping behaviour of conventional generators.…”

Isothermal Deep Ocean Compressed Air Energy Storage: An Affordable Solution for Seasonal Energy Storage

“…When the hull is filled with compressed air, the ship rises. (6) The multistage pump/turbine ternary unit is used both to pump water into the isothermal air compressor and to generate electricity by means of the isothermal decompression of the air. The multiple pump/turbine stages are connected to the same shaft and generator to reduce investment costs.…”

“…Pumped-hydro storage (PHS) and batteries are the two most used grid-scale energy storage technologies. The capital cost of batteries is rapidly decreasing [4] and might soon provide reasonably priced daily energy storage services [5][6][7]. However, batteries are not designed to store energy in seasonal cycles given the high energy storage cost (USD/kWh) [8] and self-discharge (lithium-ion batteries have low self-discharge, i.e., 1.5-5%/month, and some batteries have less than 0.5% after 400 days [9]).…”

FPGA-Based Real-Time Simulation of Dual-Port Submodule MMC–HVDC System

“…The control and protection system has an important function in the secure and reliable operation of the power grid. The hardware-in-loop (HIL) test based on real-time simulation is used to verify the correctness of the protection devices' action and the effectiveness of the control strategy in HVDC flexible transmission [4][5][6]. As the transmission voltage level increases, the switching element groups sometimes need to be used in parallel.…”