Voltage sensorless based virtual flux control of three level NPC back-to-back converter dfigunder grid fault

In this paper, a harmonic elimination of grid and stator currents of doubly fed induction generator (DFIG) in case of grid fault without line voltage sensors is proposed . This can be achieved by compensating power based on virtual flux voltage sensorless technique. Direct power control with space vector modulation (DPC-SVM) is used to control both grid-side (GSC)and rotor-side converters (RSC). To achieve the control objective, compensated active and reactive powers are calculated based on virtual flux technique with balanced and harmonic free current as a control target. A theoretical analysis of active and reactive powers under unbalanced voltage source is clearly demonstrated and the effect of grid fault on the performance of DFIG is profoundly discussed. Simulation results verified the effectiveness of the modified control strategy.

• doubly fed induction generator
• grid faults
• voltage sensorless control
• three-level NPC converter
• back-to-back converter
• direct power control
• space vector modulation
• harmonic elimination
• voltage unbalance
• active and reactive power compensation
• rotor side converter
• grid-side converter

• 7 — Affordable and clean energy
• 9 — Industry, innovation and infrastructure

• Wind Turbine Control Systems
• Sensorless Control of Electric Motors
• Multilevel Inverters and Converters
• doubly fed induction generator
• grid faults
• voltage sensorless control
• three-level NPC converter
• back-to-back converter
• direct power control
• space vector modulation
• harmonic elimination
• Electrical and Electronic Engineering
• Engineering