In recent years, the tremendous growth of converter-based renewable energy sources has led to the increased complexity of converter controls thus further complicating the management of energy production. Additionally, the reliability and sustainability of energy production are poised to gain more importance in modern power grids. This issue becomes more apparent when the grid encounters abnormal conditions such as faults and voltage drops. In this situation, the grid has set certain rules called grid codes. The grid codes don't permit renewable energies to disconnect from the grid in the grid fault conditions. The renewable energies should help the grid to improve the stability and remain connected to the grid to support the active power injection in the post-fault time. Since a considerable amount of renewable energies connect to the grid by converters, it is most important to improve or replace the converter's controller with effective controller strategies.

Although there are several fault ride-through (FRT) techniques, most of them need high investment and maintenance. Hence, improving the controllers of renewable energies' converters has recently been introduced to enhance FRT capability. This solution seems to be a more effective and affordable approach to comply with grid codes. There are several types of converter-based renewable energies. For instance, the permanent magnet synchronous generator may use full power back-to-back converter, the doubly-fed induction generator can consider partial power back-to-back converter, and photovoltaic panels may connect to the grid by one-stage or two-stage converters. In all of these types, a new or improved converter control technique can be used to enhance FRT capabilities. Examples range from changing the controller references or controller structure, to using the robust controller, or using predictive or intelligent controllers, or combining control methods, etc.

This Special Issue aims to solicit contributions to fundamental research on improving the controller of converter-based renewable energies to enhance FRT capability. Submissions discussing and introducing a new control algorithm and/or representing new structure of converters and controllers to enhance FRT capability are also welcome. We also seek studies on robust, artificial intelligence, model predictive controllers and also using deep learning methods applicable to converter-based renewable energies. Review articles discussing the current state of the art are also welcome.

Potential topics include but are not limited to the following:

• Low voltage ride-through
• High voltage ride-through
• Grid faults
• Implementation of grid code
• Robust control
• Deep learning and artificial intelligence
• Model predictive control
• Permanent magnet synchronous generator
• Doubly-fed induction generator
• Photovoltaic systems
• Grid integration of renewable energy