Design of a dual-layered tilt fuzzy control structure for interconnected power system integrated with DFIG

Abstract

The doubly fed induction generators based wind power plant is extensively used as a renewable energy source; however, their integration with interconnected power systems may cause equal challenges as well. Since such WPPs are decoupled from the grid frequency to operate at maximum power point tracking, hence they cannot participate in effective load frequency control and cause severe deterioration in the frequency regulation of the nonlinear IPS. To address these issues, this article proposes a novel dual-layered tilt fuzzy control structure (DLTFCS), which comprises of a fuzzy tilt integral derivative with a filter as the first layer working in coherence with a fractional order proportional derivative controller as the second layer, together with an inertial frequency support scheme for WPP. The DLTFCS is developed with an intention of efficient handling of nonlinearity and parametric uncertainty of considered IPS in the presence of WPP. Further, a curated hybrid objective function is also proposed, which consists of a weighted combination of integral of time-weighted absolute error and oscillatory measure with the help of an analytical hierarchy process and is optimized by a recently devised salp swarm algorithm. The control performance of the proposed controller has been validated by extensive simulation studies under various scenarios ranging from system parametric variations, uncertainties in generation rate constraint, and governor deadband to significant variations in wind penetration levels. Extensive comparative studies suggested that the proposed control structure provides superior performance over fractional order proportional integral derivative (FOPID) and Fuzzy FOPID controller.