Synchronous Starting of Motor from Generator of Small Capacity

The results are presented of a computer study of the synchronous starting of a synchronous pumped storage generator motor from a generator having approximately 15 percent of the motor´s capacity. In synchronous starting both motor and generator are initially at rest with excitation applied. The effects of system parameters such as armature circuit resistance, generator saturation, relative excitation on the two machines, amortisseur characteristics, initial starting angle, motor friction torque, gate leakage torque, and rate of application of torque were studied. Some of the more important conclusions are: synchronous starting with a generator of 15 percent size is entirely feasible, the most important electrical parameter is the generator armature resistance, a good amortisseur is desirable on the motor, there is a maximum generator torque that can usefully be applied, and any higher torque may simply cause the generator to run away. Gate leakage torque can be a more serious limitation than friction torque.