Analysis of out of phase reclosing required for the protection of dispersed storage and generation units

One of the most important protection requirements of a dispersed storage and generation (DSG) unit is to provide protection against islanding and hence to prevent out of phase reclosing with the utility source which may occur following an undetected islanding condition. The possible effect of an out of phase reclosing to a power system containing a DSG unit has been analyzed in this work. In addition, the response of the DSG protection system to an out of phase reclosing created by a remote circuit breaker has also been evaluated. Computer simulation and test studies show that the rate of change of power protection algorithm, which is initially designed for islanding protection also shows a very good performance for reliable detection of out of phase reclosing conditions.