Low voltage ride through of doubly-fed induction generator connected to the grid using sliding mode control strategy

• Published in: Renewable energy Vol. 80; pp. 583 - 594
• Main Authors: Saad, Naggar H., Sattar, Ahmed A., Mansour, Abd El-Aziz M.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.08.2015
• Subjects: Active AC-crowbar; DC-chopper; Doubly fed induction generator; Low voltage ride through; Sliding mode control; DC-chopper; Active AC-crowbar; Low voltage ride through; Sliding mode control; Doubly fed induction generator
• ISSN: 0960-1481; 1879-0682
• DOI: 10.1016/j.renene.2015.02.054

Wind Energy Conversion System (WECS) based on Doubly Fed Induction Generator (DFIG) connected to the grid is subjected to high transient currents at rotor side and rise in DC-link voltage during voltage sag at stator/grid side. To secure power system operation wind turbines have to meet grid requirements through the Low voltage ride through (LVRT) capability and contribute to grid voltage control during severe situations. This paper presents the modeling and control designs for WECS based on a real model of DFIG taking into account the effect of stator resistance. The non-linear control technique using sliding mode control (SMC) strategy is used to alter the dynamics of 1.5 MW wind turbine system connected to the grid under severe faults of grid voltage. The paper, also discusses the transient behavior and points out the performance limit for LVRT by using two protection circuits of an AC-crowbar and a DC-Chopper which follow a developed flowchart of system protection modes under fault which achieved LVRT requirements through results. The model has been implemented in MATLAB/SIMULINK for both rotor and grid side converters. •Stator resistance of DFIG is not neglected in order to provide a real model.•Sliding mode control is implemented for active and reactive power control.•Protection schemes using crowbar and DC-chopper circuit.•Achieve of LVRT requirements and grid code in Egypt.•Develop a flowchart of system protection modes under fault.