THE APPLICATION OF POWER SYSTEM STABILIZERS IN A MULTIMACHINE GENERATING PLANT

Abstract

This thesis illustrates the effectiveness of speed input, conventional power system stabilizers in a multimachine system. The particular real power system concerned was comprised of six generating units and an infinite bus. This is a reduced order model of part of the Saskatchewan Power Corporation System. The oscillation of the system as a result of an infinite bus fault is shown to have several poorly damped frequency modes. These frequency modes were studied by using the eigen-value and eigen-vector method. The units which would give the maximum damping effects were determined using this method. Two stabilizer design methods are described in this thesis, the Root Locus Method(RLM) and the Phase Compensation Method(PCM). The RLM approach requires a system transfer function in factored form. A method of determiningthis from time-domain test data is described in detail in the thesis. The PCM approach, which is significantly simpler to apply than the RLM approach, is demonstrated also. This method is based on the approach of compensating the phase shift between the air gap flux deviation( AE' ) and the rotor speed deviation(AW) to achieve positkve damping torque to damp the system oscillation. This thesis shows that the Phase Compensation Method as compared with the Root Locus Method requires less computational work, has lower sensitivity to the precision of the models or the calculations and higher accuracy due to its use of actual system test data.