Design & Development of a fresh approach for controlling speed of Synchronous Machine

Abstract

This paper presents use of the simplified alternator for a load shedding test on a 2000 kVA, 600 V. A three-phase, four-wire alternator rated 2000 kVA, 1600 kW, 0.8 power factor, 600 V, 1800 rpm has been connected to a 1600 kW, 400 kvar inductive load. The stator neutral point is grounded. The internal impedance of the generator (Zg = 0.0036 + j*0.16 pu) represents the armature winding resistance Ra and direct axis transient reactance X'd. The total inertia constant of the generator and prime mover is H = 0.6 s, corresponding to J = 67.5 kg.m^2. Speed regulation is modeled with Simulink® blocks implementing a PI regulator. The machine is excited with a constant voltage. A three-phase breaker is used to switch out a 800 kW resistive load. The breaker is initially closed and it is opened at t = 0.2 s, resulting in a 50% load shedding. In this paper, the machine is initialized in order to start simulation in steady state and the machine dynamics with and without speed regulation has been observed.

Key Words: alternator; inductive load; stator neutral point; Synchronous Machine; speed regulation