Power Quality Issues in Grid Connected Solar Power System

Abstract

newline The fast depletion of fossil fuels and the adverse effects of burning of the fossil fuels have triggered the international scientific communities and governments to lookout for renewable clean energy sources. The solar photo voltaic energy conversion system is more power efficient. and can be used for both standalone loads and also as grid integrated sources. newlineThe major issues of concern in regard to the grid integration of solar photo voltaic source are, the MPP tracking, the reduction of ripple in the dc link current and dc link voltage, the reactive power support to the load, the reduction of harmonics and THD in the current being injected to the grid. In this research the grid integration of solar photo voltaic energy has been demonstrated using three different strategies and observed the following. newlineThe ANN based controller is found to outperform the PI and the Fuzzy Logic controllers in the management of the DSTATCOM based grid integration of solar energy. As for the THD of the source current the ANN based controller offers 4.96% as against the FLC that exhibits 5.03% and the PI controller exhibits 8.24%. Similarly, the source side power factor is maintained at 0.97 by the ANN where 0.95 and 0.93 by the FLC and the PI controllers respectively, when the load power factor is as low as 0.707. The sliding mode controller based MPPT done at the interfacing Super Lift Luo Converter is simple to be implemented and it requires only one parameter, i.e., the terminal voltage of the PV panel whereas other methods of MPPT requires the measurement of the PV voltage as well as current. A novel six phase modular multilevel converter with capacitor balancing in place of the conventional three phase converter for the DSTATCOM has been proposed and observed that the six-phase converter produces a reduced ripple of 18V peak to peak with improved ripple frequency of 600 Hz and the DC link capacitor has been reduced from 4700µF to 2200µF. The use of Hopfield Neural Network for the estimation of the switching angles for the SHE- PWM based step modulated has been found to be performing better for modulation indices 0.6, 0.7, 0.8 and 0.9 and requires minimal passive filters while exhibiting reduced switching losses. A single phase nine level inverter with reduced switches and three phase three level is simulated using MATLAB and verified experimentally. newline