Experimental implementation of optimally tuned multifunctional RLMLS driven VSC tied to single phase voltage weak distribution grid

This work presents a nature-based optimization technique for optimal control and performance enhancement of a single-phase robust least mean logarithmic square driven (RLMLS) grid connected voltage source converter (VSC) in a distribution system with the aim of feeding continuous power to the grid. Water cycle algorithm (WCA) is employed to tune the proportional-integral (PI) controller parameters of VSC to regulate DC link voltage fluctuations owing to dynamic load conditions. This results in generation of accurate loss component of current ( I_loss ) to improve the performance of VSC. The VSC acts as an active power filter and counters various power quality (PQ) problems viz; poor power factor, grid-side harmonics and reactive power burden. The pulses for the VSC are acquired by employing RLMLS control, which ensures relatively superior convergence performance and reduced computational complexity owing to its simple architecture. The proposed control demonstrates the unique property of adaptability during disconnection and reconnection of load from the system. Significantly, this work depicts the system operation under abnormal conditions of the distribution network like load decrement and increment, load disconnection and reconnection, voltage sag and swell. The suggested system is corroborated with the help of a grid integrated laboratory prototype with a maximum operating rating of 2 kW at 230 V, 20A. The operating power level is 200W, 4A at 50 V (rms) with the transformer connected to the grid. Extensive simulation and experimental results obtained on a DSP dSPACE 1104 controller verify the effectiveness of the proposed control.