Comparing the Performance of Protection Coordination and Digital Modular Protection for Grid-Connected Battery Storage Systems

This paper compares the performances of protection coordination [time setting and zone selection interlocking (ZSI)] and digital modular protection, when deployed for grid-connected battery storage systems (BSSs). The comparison between these protection management methods is made in terms of their structures, functionalities, and response capabilities. These criteria are selected to demonstrate possible impacts of the system configuration and mode of operating a grid-connected BSS on protection responses. The performance comparison among the time-setting coordination, the ZSI coordination, and the digital modular protection is conducted for different grid-connected BSSs, when operated for various fault and non-fault conditions. Performance results show that the protection coordination can offer a simple structure that is set to achieve specific response (TRIP and RESTRAIN). In addition, performance results show that the digital modular protection can offer diverse responses (TRIP, RESTRAIN, and ACTIVATE), which mandate for a digital implementation.