generators from the viewpoint of power system impacts and economic aspects. Moreover, generators should bear the opportunity cost of loss associated with this measure based on the degree of benefit they receive during normal operation. To this end, OCCTO is studying how to calculate the opportunity cost of production losses and a mechanism for settlement (Figure 3). Since there is a great demand from generation entities for early connection, the first step in the application of the N−1 intertrip scheme started in October 2018. In the first step, new generators seeking grid connection under the N−1 intertrip scheme were designated as generators subject to intertrip control, i.e., the target generator of intertrip and opportunity loss cost payer is the same entity. Substation 2L 1L Transmission Line Substation 2 Communication Device (Sending) 1 Substation Overload Detector 3 -1 Transmission Line Relay Point (If Needed) 3 -2 Generation Station Circuit Breaker Communication Route (Microwave, OP Wire) Signal for Trip or Output Decrease 5 G Communication Route (Microwave, OP Wire) G Controlling Device 4 Communication Device (Receiving) Generators 1 2 3 4 Overload Detector * Detect Overload in the Event of a N -1 Failure * Send a Trip or Output Decrease Signal According to the Amount of Overload Communication Device * Transfer Signal Generated by 1 Communication Route Communication Device * Receive Signal and Transfer to the Controlling Device (Owned by the Transmission and Distribution Utility Company) 5 Controlling Device * Conduct Operation Based on the Received Signal (Owned by the Generator Owner) * Precise Configuration Such as the Number of Communication Routes and the Way of Communication Should Be Decided Based on the Grid Condition Subject to the N -1 Intertrip Scheme figure 5. The system configuration of the N−1 intertrip scheme. OP: optical fiber. march/april 2021 ieee power & energy magazine 75