Power System Small Signal Stability Analysis and Control

4.6 Effect of excitation system

In this section, the effect of excitation system on the small-signal stability performance of the SMIB system is examined in frequency domain [3]. For simplicity, let us assume that the exciter is simply a high constant gain K_A, i.e., T_A = 0.

Now from Equation (4.70), T_AΔE_fd = − ΔE_fd − K_AK₅Δδ − K_AK₆Δ$E_q^{\prime }$ + K_AΔV_ref with T_A = 0 and ΔV_ref = 0 gives

$0=-\mathrm{\Delta }{E}_{\mathrm{fd}}-K_{\mathrm{A}}{K}_5\mathrm{\Delta }\delta -K_{\mathrm{A}}{K}_6\mathrm{\Delta }{E}_q^{\prime }$

  (4.76)

$\therefore \mathrm{\Delta }{E}_{\mathrm{fd}}=-K_{\mathrm{A}}{K}_5\mathrm{\Delta }\delta -K_{\mathrm{A}}{K}_6\mathrm{\Delta }{E}_q^{\prime }$

  (4.77)

Again, from the ...