On the Comparison Between the Protection Coordination and Digital Modular Protection for Grid-Connected Battery Storage Systems

This paper presents a comparison between the protection coordination (time-setting and zone selection interlocking (ZSI)) and digital modular protection for applications in grid-connected battery storage systems (BSSs). The comparison between the these methods is made in terms of their structures, functionalities, and response capabilities. These criteria are selected to demonstrate the possible impacts of the system configuration and mode of operating a grid-connected BSS on the generated protective responses. The comparison between the time-setting and ZSI coordination, and digital modular protection methods is conducted different grid-connected BSSs, when operated for various fault and non-fault events. Test results show that the protection coordination methods can offer a simple structure that is accompanied with a specific functionality (TRIP and RESTRAIN). Moreover, test results show that the digital modular protection can offer a diverse functionality (TRIP., RESTRAIN., and ACTIVATE) and that is accompanied with mandates for a digital implementation.