Field testing of a local and automatic control for flexible loads

New, intelligent infrastructure should enable network operators to control flexible loads, such as electrical storage heaters, beneficially for the distribution network. Depending on e.g. consumer type and location, the distribution network operator (DSO) has to generate a variety of different schedules. The approach of this research project was to implement the basic logic for generating timetables in a control box on site. It would be possible to adapt the schedule to the current, local grid status. In the case of high photovoltaic feed-in, the on-times of the loads would be shifted to the daytime hours, with low photovoltaic feed-in into the night-time hours. The schedule generation is exclusively based on local voltage measurement data and stored, statistical evaluated values of the last few days. Five prototypes with integrated voltage measurement, data processor for local timetable generation and control outputs were set up, installed and operated in private households. The schedule generation was found to work reliably and the adaption of load periods to the local network status is possible, without the need for an external communication. Furthermore, influence of input parameters on the generated timetable was investigated based on the existing measurement data and statistically evaluating the results.