A Case Study on the LVRT Capability of an Egyptian Electrical Grid Linked to the Al-Zafarana Wind Park using Series Resistor

Abstract

In wind farms, a doubly fed induction generator (DFIG) has proven to be the most successful wind power generator in recent years. DFIG features various speeds of operation and autonomous management of reactive and active powers. Nevertheless, the extreme DFIG sensibility to voltage dips brings a lot of defiance in terms of complying with grid code regulations set by the electrical utility operators. Now, these grid regulations impose tougher constraints, particularly for low-voltage ride-through (LVRT). Indeed, this disruption brought on by the stator circuit affects the generating system. Originally, when a failure occurred, generators had to be disconnected. In time, a disconnect could cause the entire system to fail. Recent grid codes require that in addition to meeting operating irregularities like the dc-link voltage and stator and rotor currents, the generators also remain connected. To increase the LVRT capacity for the Egyptian Electrical Grid linked to the Al-Zafarana Wind Park. This article introduces the design and modelling of a protection scheme employing a series resistor. The protection scheme ensures the safety of energy converters, rotor circuits, and dc-link capacitors while limiting rotor currents, dc-link voltages, and torque changes. The effectiveness of the protective scheme was also assessed for asymmetrical and symmetrical fault situations. Matlab/Simulink is used to produce the simulation findings. According to the simulation findings, the protection scheme demonstrated an effective solution for improving the LVRT feature, of the Egyptian Electrical Grid linked to the Al-Zafarana Wind Park.