Autonomous Load Shedding in a Nanogrid using DC Bus Signalling

Including load shedding in the system control strategy for a small standalone hybrid power system such as a nanogrid is beneficial since the peak generation requirement is reduced and the system is protected from a complete collapse under overload conditions. Autonomous load shedding can be implemented in a nanogrid that uses DC bus signalling for source scheduling by shedding loads when the DC bus voltage decreases to a level that signals an overload condition. This paper explains the control requirements for the system interface converters that is required to permit load shedding and explains a procedure for implementing a prioritized load shedding scheme in a practical system. Experimental results are included to illustrate the operation of this control strategy