On a 1000-MVA common base, a two-area system interconnected by a tie line has the following parameters:

The two areas are operating in parallel at the nominal frequency of \(60 \mathrm{~Hz}\). The areas are initially operating in steady state with each area supplying \(1000 \mathrm{MW}\) when a sudden load change of \(187.5 \mathrm{MW}\) occurs in area 1. Compute the new steady-state frequency and change in tie-line power flow (a) without LFC, and (b) with LFC.

Area Area Frequency Response Characteristic Frequency-Dependent Load Coefficient Base Power Governor Time Constant Turbine Time Constant B 0.05 per unit = D = 0.6 per unit 1000 MVA Tgl = 0.25 s = 0.5 s 2 B2 0.0625 per unit D2 0.9 per unit 1000 MVA Tg2 = 0.3 s T12 0.6 s