Adaptive Control of DC Link Voltage in a DFIG-Based Hybrid Grid-Interactive System Using Gaussian Kernel Least Mean Sixth Adaptive Filter

The interoperability of wind and solar energy is a potential alternative to improve reliability and reduce the probability of an energy supply crisis. Due to the stochastic nature of both the sources, maintaining high quality performance in grid-intertie hybrid energy systems, particularly for nonlinear loads, is essential for efficient use of energy. This article presents a novel Gaussian kernel least mean sixth (GKLMSi) grid interactive algorithm for the hybrid renewable energy system along with adaptively controlled dc link voltage. GKLMSi adaptive control effectively tracks various time varying power quality events such as, voltage fluctuations, load disturbances, reactive power variations, and harmonic parameters that are of high-order nonlinearities. The adaptive dc link voltage control reduces the stress on the converters during voltage fluctuations and generates sufficient dc link voltage reference for the converter current control. This minimizes switching losses and enhances the reliability and effectiveness of the system especially during the abnormal voltage operations.