Enhancement of new rotor resistance unit for doubly fed induction generator-based wind turbines

•A new rotor resistance unit was developed for low voltage ride through capability in a doubly fed induction generator.•Stator and rotor dynamic modeling were developed against symmetrical and symmetrical faults.•Electromotive force models are developed in stator and rotor circuits.•A comparison was made of symmetrical and symmetrical faults with and without proposed model. It is very important to obtain smooth power and limit over-currents in grid-connected doubly fed induction generator (DFIG)-based wind turbines. Therefore, the rotor resistance unit can be used for power and over-currents control in DFIG. However, it may be insufficient to reduce oscillations in large power systems. This study aims to develop a new rotor resistance unit for low voltage ride through (LVRT) capability in DFIG. Moreover, electromotive-force (emf) models have been also developed in the stator and rotor circuit. The stator emf model of the simulation study was developed in the DFIG for accuracy and speed, while the rotor emf model was developed for over-current occurring in transient situations. In using the new rotor resistance unit and the stator-rotor emf, it was observed that the system stabilized in a short time, and the oscillations formed by the balanced and unbalanced faults on the grid side were damped.