Shaik, Abdul Gafoor

Power quality issues in weak grids with large impedance pose significant challenges that limit wind energy (WE) penetration levels and the performance efficiency of existing WE infrastructure. The presence of non-linear (NL) loads at the point of common coupling (PCC) further restricts these levels. This paper addresses these challenges by introducing an additional distributed static compensator (DSTATCOM) at the PCC, controlled by a higher-order Delayed Least Mean Fourth (DLMF) algorithm. The proposed DLMF control algorithm estimates the active and reactive components of the load current by updating their respective weights with appropriate delays, considering variations in loads, DC-link voltage, and wind energy generation. The MATLAB implementation of the proposed control is designed and validated through experimental investigations. These investigations involve varying short circuit ratios, wind speeds, and the presence of NL loads. The results demonstrate that the proposed method can enhance wind penetration levels in weak grids by up to 30%.

The synchronization of the Doubly-Fed Induction Generator (DFIG) into the weak AC grid is significantly affected due to the reactive power limitations associated with the built-in converter of the existing Wind Energy (WE) system. This is further restricted due to non-linear loads and Power Quality (PQ) deterioration. Therefore, there is a strong need for a system capable of managing reactive power without disturbing the existing infrastructure of WE sources. This paper proposes a novel reactive power-based solution for synchronizing the DFIG to the weak grid with high WE penetration by mitigating PQ disturbances and managing reactive power at the interconnection point using an additional Distribution-Static Compensator (DSTATCOM). A feed-forward second-order-based adaptive algorithm controls this reactive power compensator. The adaptive control extracts the active and reactive weights of load current to generate the reference signals by continuously tracking grid voltage, wind generation, and DC-link voltage. The proposed novel approach has been successfully implemented in MATLAB and validated with a laboratory-based experimental setup. The transient and steady-state analysis reveals the practical applicability of a proposed novel synchronization approach with a high WE penetration level.