The present invention discloses a network based distributed generation and coordination of a transition operation mode when the integrated protection method DG capacity increase, thus increasing the short-circuit current level, DG properties from the original "pure load" is converted to "small power" Nature existing protection and switch breakpoint has been unable to meet the needs of transition situations. In the present embodiment and the conventional protective switch break condition, and by a continuous operation mode matching, continuous optimization scheme, and the state quantity information continuous exchange, and a control interface to form a protective system adapted to achieve the system security operation and continuous supply of dual purpose. Determining a range of fault isolation switch off the new boundaries need to collect the points determined, and also considering whether the consequent upon determining the boundary point and splitting system islanding operation mode stable operation.