Simulation modeling of parallel operation of wind power plants

At present, despite the rapid development of wind energy, insufficient attention is paid to the issue of the impact of parallel operation of wind power plants with semiconductor converters on the quality of generated electrical energy. Thus, studies aimed at analyzing harmonic distortions of voltage and current in the power supply system with several wind generators that lead to significant additional losses of electrical energy, are relevant and necessary to improve the energy efficiency of wind energy systems. The study has been conducted using a simulation model of parallel operation of network wind power plants with a three-phase synchronous generator with permanent magnets developed in the Matlab/Simulink software. The object of the research is a power supply system consisting of six wind power plants connected to the grid using a transformer substation. The subject of the research is the energy efficiency of parallel operation of wind power plants of a wind energy system. The authors have obtained the results of modeling three synchronous generators with 4Q-converters to study the parallel operation of wind power plants as part of a wind energy system introduced into the network in maximum power mode. It is established that under unequal operating conditions of the plants due to different wind speeds (from 12 to 15 m/s) active powers equal to 1,39, 1,46 and 1,5 MW are generated respectively. The total generated active power of three generators on the 690 V bus is 4,35 MW, and the reactive power is 250 kvar. Additional losses of active power of higher harmonics amount to 10,48 % of the main losses in the elements of the power supply system. The values of the coefficients of harmonic component of voltage at a voltage of 690 V exceed the established standards. The developed model is adequate and provides reliable modeling of wind energy system modes during parallel operation of wind power plants with synchronous generators with permanent magnets. Based on the results of modeling and calculation of capacities, the coefficients of higher harmonics and losses of electric power, it has been proved that parallel operation of generators increases the negative impact of powerful nonlinear devices on the electric grid.