Overall fuzzy logic control strategy of direct driven PMSG wind turbine connected to grid

The fuzzy logic strategies reported in the literature about the control of direct drive permanent magnet synchronous generator (PMSG) connected to grid are limited in terms of inclusiveness and efficiency. So an overall control based on fuzzy logic and anti-windup compensation is proposed in this paper. Aiming at the inadequate of hill climb search (HCS) MPPT with fixed step size, the fuzzy logic is introduced in the stage of "generating rotor speed reference" to overcome the oscillations and slowness in traditional method. PI controllers are replaced by anti-windup fuzzy logic controllers in the "machine side control" stage and in "grid side control" stage to pertinently regulate the reference parameters. Then comparison tests with classical methods are implemented under varying climatic conditions. The results obtained demonstrate that the developed control is superior to other methods in response time (less than 4.528E-04 s), precision (an overshoot about 0.41%) and quality of produced energy (efficiency is 91%). The study verifying the feasibility and effectiveness of this algorithm in PMSG wind turbine connected to grid

Smart municipal energy grid within electricity market

A smart municipal energy grid including electricity and heat production infrastructure and electricity demand response has been modeled in HOMER case study with the aim of decreasing total yearly community energy costs. The optimal configurations of used technologies (photovoltaic plants, combined heat and power plants, wind power plants) and sizing, with minimal costs, are presented and compared using three scenarios of average electricity market price 3.5 c€/kWh, 5 c€/kWh and 10 c€/kWh. Smart municipal energy grids will have an important role in future electricity markets, due to their flexibility to utilize excess electricity production from CHP and variable renewable energy sources through heat storage. This flexibility enables the levelized costs of energy within smart municipal energy grids to decrease below electricity market prices even in case of fuel price disturbances. With initial costs in the range 0- 3,931,882 €, it has been shown that economical and environmental benefits of smart municipal energy grids are: the internal rate of return in the range 6.87-15.3%, and CO2 emissions in the range from -4,885,203 to 5,165,780 kg/year. The resulting realistic number of hours of operation of combined heat and power plants obtained by simulations is in the range 2,410- 7,849 hours/year.This is the peer-reviewed version of the article: Batas-Bjelic, I., Rajakovic, N., Duic, N., 2017. Smart municipal energy grid within electricity market. Energy 137, 1277–1285. [https://doi.org/10.1016/j.energy.2017.06.177