The increase of renewable power sources in today's energy production systems results in high non-deterministic fluctuations in energy distribution network. At the same time, the use of nonlinear switching power supplies is more and more widespread nowadays, that creates serious nonlinear distortion in the line. In addition, the insufficient energy storage capacity commonly available in public energy distribution networks makes it very difficult to operate it an efficient and balanced way. Therefore, a novel control method for combining small domestic power plants using renewable energy and electric vehicle battery chargers where the battery can be used as temporal energy storage is proposed in this paper. The method is not only capable of optimizing the working point of the plant, but also implements active power factor (PF) correction and lowers the extant harmonic distortion in the line. In addition, the proposed control method allows one to create systems that can absorb the peaks of power production, or can feed power back into the grid in fluctuating energy production. The novel element is the voltage level controller which independently optimizes the effective value of the voltage at the connection point. This controls the energy flow direction between the grid, the renewable power source and the EV batteries. The system is able to communicate with an external controller through a Smart Grid Interface to be an element of a larger grid control scheme as an executer part. The proposed controller has been verified by simulation in Matlab environment, and as a result, substantial improvement of the output voltage and current effective value and waveform could be achieved. Robustness of the method against nonlinear loads has also been tested.
ASJC Scopus subject areas
- Chemical Engineering(all)