This paper analyses the synchronization problem of a generator onto power system without satisfying synchronization condition. The main focus of the paper is on the impact of the dc component of the current in the high voltage circuit breaker during its close-open operating cycle. Using real time measurements of currents/voltages and angles during the close-opening cycle of high voltage generator circuit breaker and the impact of the dc component of current in context of interrupting large magnitude of current from the circuit breaker. In addition, the paper describes a study case model and the results of simulations performed using the software EMTP-ATP of an actual incident that occurred during the inadvertent synchronization of a large 339 MW, 24 kV generator to the grid.
 KOSTT, “Electrical Equipment Code,” 2nd Edition, KOSTT, Kosovo, 2009. www.kostt.com
 KOSTT, “Grid Code,” 2nd Edition, KOSTT, Kosovo, 2010. www.kostt.com