Evaluation of a Decentral Grid-Oriented Demand Side Management Algorithm for Low Voltage Grids in Special Grid Situations

Abstract:
Increase in decentral volatile power generation on the one hand and power demand like charging stations for electric vehicles and heat pumps for homes on the other leads to a higher strain on the German distribution grid. One possible solution is demand side management of flexible loads with the decentral flair algorithm in low voltage grids. This study examines the behavior of the flair algorithm in the two special grid situations of grid restoration after a power outage and island grid operation with a limited power source. The special grid situations are modelled by modifying the voltage of the medium voltage grid on the high voltage side of the transformer. For grid restoration, the time and the length of the power outage are varied. For island grid operations scenarios with different power supply voltages are evaluated. According to the simulations in this study the usage of the flair algorithm has a benefit regarding network systems utilization and postponing flexible loads to less critical grid situations. In general, the parameters of the algorithm should be set to aid in special grid situations, either by overwriting them by the grid operator or by detecting a special grid operation and acting accordingly. At grid restoration, a lower recovery mains voltage can postpone flexible demand and separate it from unflexible backlog demand. At island grid operations, coordination between the power source and the flair algorithm is essential. Setting the power supply voltage to be dependent on the utilization can decrease power demand without a good demand forecast.