State-of-energy balancing control with cascaded H-bridge for second-life batteries

Abstract

Battery energy storage systems (BESS) are fre-quently utilized to support the power grid. Second-Life batteries (SLBs) are considered as a potential solution to reduce the cost of BESS in stationary applications. However, using SLBs has certain challenges due to the non-uniform State-of-Charge (SOC) and State-of-Health (SOH) among the battery modules. This study examines two control strategies for a cascaded H-bridge (CHB) topology used for BESS applications. The possibilities for flexible control of the BESS are enabled by employing a CHB topology. By utilizing the CHB topology, each battery module can be individually charged and discharged. Two battery energy management system (BEMS) techniques are proposed based on the batteries' State-of-Energy (SOE): 1) continuous and 2) discrete balancing techniques. The experimental tests demonstrate the advantages of the proposed solutions in terms of individual balancing control when being applied to SLB.

Battery energy storage systems (BESS) are fre-quently utilized to support the power grid. Second-Life batteries (SLBs) are considered as a potential solution to reduce the cost of BESS in stationary applications. However, using SLBs has certain challenges due to the non-uniform State-of-Charge (SOC) and State-of-Health (SOH) among the battery modules. This study examines two control strategies for a cascaded H-bridge (CHB) topology used for BESS applications. The possibilities for flexible control of the BESS are enabled by employing a CHB topology. By utilizing the CHB topology, each battery module can be individually charged and discharged. Two battery energy management system (BEMS) techniques are proposed based on the batteries' State-of-Energy (SOE): 1) continuous and 2) discrete balancing techniques. The experimental tests demonstrate the advantages of the proposed solutions in terms of individual balancing control when being applied to SLB.