Voltage considerations during generator synchronizing

When paralleling generators, it is necessary to match the characteristics of the two systems as closely as possible. This is accomplished by minimizing the phase-angle difference, slip frequency and voltage difference between the two systems. Using the voltage magnitude alone to calculate this difference may not provide the expected results. When the phase angle is taken into account, the vector difference of the voltages may lead to greater values than simply using the magnitude difference. This paper discusses the application of synchronizing and introduces the concept of utilizing the voltage vector difference to ensure proper synchronizing while minimizing stress to the system.