Sensitivity and transient stability analysis of fixed speed wind generator with series dynamic braking resistor

This chapter investigates the sensitivity and transient stability of fixed speed wind turbine (FSWT)-driven induction generator (IG) including series dynamic braking resistor (SDBR). The effects of the system parameters and operating conditions on the transient characteristics of the system with and without SDBR are also studied. The IG is coupled to the grid via a step-up transformer and double-circuit transmission line, where SDBR is utilized to enhance the transient stability for short time in the course of network disturbance. The role of SDBR is to mitigate the destabilizing depression of electrical torque; thus it improves the stability of the wind generator during fault condition. Eigenvalue analysis is accomplished to present the power system small signal stability analysis. The relations between the system modes and the state variables are analyzed in light of modal and sensitivity analyses. Moreover, the dynamics of the system are analyzed under voltage dip conditions as well as demonstrating the effect of system parameter variation in transient conditions with and without SDBR. SDBR control scheme is engaged to improve IG transient response and mitigate the oscillations of electrical torque, terminal voltage, and generator speed. The results of the theoretical analyses are verified using a time-domain simulation model built in MATLAB/SIMULINK.