Analysis of power flow control strategies in heterogeneous battery energy storage systems

This paper provides a method for the systematic analysis of several power flow control strategies (PFCS) in a heterogeneous multiple battery energy storage system (BESS). Due to the difficulty of comparing different PFCS in different scenarios and system configurations, in total five static and dynamic PFCS are investigated in two distinct application-oriented scenarios and are assessed by two target indicators, namely performance and efficiency. A simulation model based on a heterogeneous multiple BESS with a hierarchical control scheme is set up, the components of the model are validated and a real test bench verifies the functionality of the PFCS. Simulations in MATLAB/Simulink are carried out to analyze the performance and the efficiency of the applied PFCS in an energy-and a load-related application scenario. This approach allows a systematic comparison of PFCS in consideration of varying system parameters and different scenarios. The results suggest that depending on the objective to be achieved and the applied application scenario, the choice of the right PFCS is crucial. Thus, this paper provides a workflow to analyze the selection of proper PFCS. Furthermore, heterogeneity plays a decisive role in analyzing different PFCS, since operating limits of the BESS become more significant.