Voltage Dependent Demand Response with Dynamic Hysteresis Thresholds in DC Microgrids

DC renewable energy sources and dc loads are gaining attraction and they are preferably connected in dc microgrids. To increase the availability of dc microgrids, voltage dependent demand response should be used to switch off low priority loads in case of insufficient supply. This is possible even without communication with the loads. In this paper it is shown that using a voltage hysteresis with fixed thresholds to switch loads on and off, does not provide a general solution and oscillations can occur in specific cases. Dynamic hysteresis thresholds are introduced as a mean for devices to autonomously learn the present behavior of the grid to which they are connected.