Modelling and control of multi-type grid-scale energy storage for power system frequency response

Abstract

As a result of the increasing integration of renewable energy sources, power system is changing to a low inertia system with intermittent power supply. Frequency stability is therefore difficult to be maintained. Rather than increasing the spinning reserve capacity from conventional fossilfuel generators, the use of Energy Storage System (ESS) for frequency response is considered as a technically viable lowcarbon solution. To facilitate the grid-level study which aggregates a number of widespread small-size ESS, simplified models of multi-type ESSs including batteries and flywheels were developed. A generalized frequency controller was developed and applied to the aforementioned types of ESS. The controller coordinates the response amongst a population of ESS based on the units' State of Charge indicator. An adaptive droop control is combined with the coordinated control to guarantee a linear frequency response provided by a smaller number of ESS units. The number of charging and discharging of each unit is therefore reduced which prolongs the lifetime of the ESS units. Case studies were carried out by connecting a number of multi-type ESSs to a simplified GB power system model. Results show that the grid-scale ESSs are able to provide frequency response similar to but faster than frequency-sensitive generators. Implementation of ESS is therefore technically feasible to support the grid frequency stability with the reduction in the spinning reserve capacity.

Research on Modeling and Hierarchical Scheduling of a Generalized Multi-Source Energy Storage System in an Integrated Energy Distribution System

“…By coordinating the available resources of conventional energy storage, multi-energy flow and demand response, GMSES is characterized by its advantage of combining high power density and high energy density [25]. Complementary potential can be found in the coordination of GMSES controllable resources, as it varies in time scales and operation characteristics, as shown in Figure 1.…”

“…Currently, some typical CESs (i.e., lead-acid battery, lithium-ion battery, etc.) have been widely utilized for EPS applications [25].…”

“…Operation performance of GMSES can be reflected via VSOC, and in this regard, GMSES overcharge or overdischarge can be prevented, which is vital for safe and stable operation. Considering the various characteristics of GMSES resources, the integrated GMSES VS is defined based on the power output and the integrated weight factor of each part of GMSES, as illustrated in Equations (25) and (26). represent the integrated weight factor and the consumed power of each kind of GMSES resources.…”

Offline Photovoltaic Maximum Power Point Tracking

“…In [5], flywheel energy storage system is shown to provide frequency support. Battery storage systems can also be used to provide frequency support as shown in [6]. This is because they are fast-acting and can increase active power supply in the time-scale of inertia response.…”

Impact of inertia emulation control of grid-scale BESS on power system frequency response

“…The influence of different ESS, specifically BESS and flywheels, on large power system frequency responses were studied by [2]. In another paper, [3] develops two control strategies, Coordinated Constant Droop Control (CCDC) and Coordinated Adoptive Droop Control (CADC), to emulate the grid inertial response with the aid of BESS and Flywheels.…”