Inverters are usually programmed using mathematical functions and equations with certain coefficients. In the centralized power systems, the grid parameters are unchangeable, so it is enough to calculate the coefficients once. This task is more complicated for the distributed generation systems, where, due to the presence of many independent power suppliers, the grid parameters constantly change, which requires regular recalculation of coefficients. This, in turn, complicates the quality control of power from various sources, including solar panels and diesel generators used for remote areas supply.
The Skoltech scientists tried to solve this problem by developing a collector algorithm that automatically recalculates coefficients and unifies power quality of the electricity entering the grid. The algorithm allows analyzing data from the sources available in the grid and generating a control signal which provides 50 Hz AC frequency at the output, which is common for Russia and most European countries.
“During the research, we created a network model and a more detailed model of the inverter. Thanks to them, we are able to check different controller algorithms, their stability, and efficiency. Then we validated the results with experimental data: we connected a real inverter to the grid, modeling the situation when there is a local load and part of the energy goes into the grid. In the lab, we mainly work with low-power inverters suitable for home use. We have excellent equipment for a detailed real-time simulation. It can be used to simulate any grid with any number of inverters and any parameters,” Skoltech quotes Ilya Veretennikov, a Smart Grid Laboratory engineer.
The authors of the study plan to fully automate the algorithm, so that integration of the isolated sources in a common grid would be as simple as connecting various devices to a personal computer.
