Application of a coordinated design method for under-excitation limiters in a multi-machine power system

The design of the under-excitation limiters (UEL) in the multi-machine Singapore power system is considered. Based on the technique described by the authors previously (see IEEE Trans. Power Syst., vol.14, no.4, p.1279-84, 1999), the frequency response method has been extended to include the interactions between generators in the power system such that the design of the UEL can be carried out in a systematic manner. By coordinating the reactive power compensation scheme with the generator reactive power absorption capability, a more effective utilization of the network resources can be achieved.