EFFECTS OF LOAD MODELS ON THE OPERATION OF THE EXISTING CONTROLLERS IN AC/DC SYSTEMS

This paper investigates the effects of load models on dynamic performance of the AC/DC systems. In general electric loads can be classified as static and dynamic loads. Static load is modeled as a nonlinear function of the load bus voltage and dynamic load is modeled by an equivalent induction motor. In this paper DC power modulation, AC power modulation and power system stabilizer (PSS) have been considered as controllers. The dynamic model of the AC/DC system is derived using component connection model (CCM) technique. In this technique the eigenvalue sensitivities can be easily calculated. Eigenvalue sensitivities and simulation results show that static and dynamic load characteristics can have a considerable effect on the system dynamic performances.