Grid-connected renewable energy sources: Review of the recent integration requirements and control methods

The growing of renewable power generation and integration into the utility grid has started to touch on the security and stability of the power system operation. Hence, the grid integration requirements have become the major concern as renewable energy sources (RESs) such as wind and solar photovoltaic (PV) started to replace the conventional power plant slowly. In line with this, some of the new requirements and technical regulations have been established to ensure grid stability. This study aims to fill the gap and conduct an updating review of the recent integration requirements and compliance control methods regarding the penetration of renewable power plants to the power grid. The review is conducted by a comparing of the key requirements related to voltage stability, frequency stability, voltage ride-through (VRT), power quality, active and reactive power regulations towards grid stability. In order to fulfill these requirements, different control methods have been recently proposed. Accordingly, this paper compares and reviews the state-of-the-art solutions for compliance technology and control methods. Furthermore, a broad discussion on the global harmonization of the integration requirements, challenges, advantages and disadvantages is also highlighted. The rigorous review indicates that although the recent integration requirements can improve the grid operation, stability, security, and reliability, further improvements are still required with respect to protective regulations, global harmonization, and control optimization. Various recommendations for future research related to the integration and technical regulations of RESs are then presented. In sum, the insights provided by this review may aid the development of smooth and stable grid integration of RESs, help developers and researchers to develop the design and control strategies in the sense of current requirements. Additionally, assist power system operators in establishing or improving their own requirements in comparison with the remaining international requirements.