Control of a population of battery energy storage systems for frequency response

Abstract

The control of multiple battery energy Storage systems (BESSs) to provide frequency response will be a challenge in future smart grids. This paper proposes a hierarchical control of BESSs with two decision layers: the aggregator layer and the BESS control layer. The aggregator layer receives the states of charge (SoC) of BESSs and sends a command signal to enable/disable the BESS control layer. The BESS controller was developed to enable the BESSs to respond from the highest to lowest SoC when the frequency drops, and from lowest to highest when it rises. Hence, the BESS's response is prioritised to reduce the impact on the power system and end-users during the service. The BESS controller works independently when a failure occurs in the communication with the aggregator. The dynamic behaviour of the population of the controllable BESSs was modelled based on a Markov chain. The model demonstrates the value of aggregation of BESSs for providing frequency response and evaluates the effective capacity of the service. The model was demonstrated on the 14-machine SouthEast Australian power system with a 14.5GW load. 254MW of responsive capacity of aggregated batteries was effective in reducing the system frequency deviation below 0.2 Hz following a sequence of disturbances.

A Novel and Optimal Battery Sizing Procedure Based on MG Frequency Security Criterion Using Coordinated Application of BESS, LED Lighting Loads, and Photovoltaic Systems

“…Therefore the battery with the size of 4.44 kW is sufficient to handle PFC without being damaged. It should be noted that if the battery sizing method presented in [7]- [10] was used, the power rating of the battery would be equal to the maximum injected/absorbed power, which is 33.86 kW. Hence using the overloading characteristics results in almost 87 % reduction of the required power rating of the battery for PFC.…”

“…The initial values of P LEDLLs and D MPP are 7.3 kW and 0.52, respectively. Based on the explanations given at the end of the section 2-D, the maximum limits of K Dut_Fre and K LEDLLs are set to 2.8 and 14600 using equations (10) and (4), respectively. The maximum limit of K BESS is set to 67750 which was determined in the previous section for maintaining the frequency within the allowable limits using only BESS.…”

“…The authors in [9] focused on the impact of the PFC provided by BESSs on the transient response of electric grids. In [10], a hierarchical control of BESSs for controlling multiple BESSs to provide frequency response is proposed. The studies in [7]- [10] mainly considered the nominal power of the batteries for PFC application.…”

“…In [10], a hierarchical control of BESSs for controlling multiple BESSs to provide frequency response is proposed. The studies in [7]- [10] mainly considered the nominal power of the batteries for PFC application. However, there are some batteries with overloading characteristics are capable of fast discharge/charge for a short period.…”

Coordination of Generators and Energy Storage to Smooth Power Fluctuations for Multi-Area Microgrid Clusters: A Robust Decentralized Approach

“…In [11], the sliding mode control (SMC) is proposed to design as the load frequency controllers. In addition, ESS can effectively provide frequency support in MG clusters and smooth the power fluctuations caused by the intermittent and stochastic output power of renewable generations [12], [13]. In [12], the battery and supercapacitor-based hybrid storage system effectively handles the uncertainty in both load side and generation side and provides better frequency response.…”