Analytical Assessment Of The Impact Of Stator-series Passive Resistive Hardware (ssprh) On Transient Response And Fault Current Contribution In Dfig Based Wind Turbines

Analytical assessment of the impact of stator-series passive resistive hardware (SSPRH) on transient response and fault current contribution in DFIG based wind turbines.

Abstract:   

The use of stator-series passive resistive hardware (SSPRH) is an alternative, efficient and cost effective approach for the low voltage ride through (LVRT) capability improvement in DFIG based wind turbines (WTs). This paper first analytically examines the rotor dynamics with the SSPRH during the voltage dip. Then the paper expands analytical expressions for the resistance design in SSPRH and proposes a simple mathematical formula to determine the minimum required SSPRH resistance to meet the LVRT requirements. Next, the impact of the SSPRH on contribution of DFIG to the fault is studied analytically. At the end, transient performance of DFIG with the SSPRH approach is investigated and compared with the crowbar hardware. The investigations comprise the phase plane plots of the stator fluxes and rotor back-emf voltages, and time domain simulations of the rotor back-emf voltage, rotor current, stator current, and electromagnetic torque. It shown that by using the SSPRH, the peak values and oscillations of the DIG transient responses reduces significantly.