Saudi Arabian Grid Code May 2024

System Restoration 4.7.5.1 To ensure that in the event of a Partial or Total Shutdown of the Transmission System, normal supply is restored to all Users as quickly and as safely as practicable, it is necessary to provide in the Grid Code a mechanism on how such Partial or Total Shutdown of the Transmission System is to be dealt with, and to ensure that the necessary procedures and facilities are in place to support rapid re-establishing of the Shutdown parts, and to restore Supply to Users. Chapter 4 - Operating Code The Saudi Arabian Grid Code Updated Version: May 2024 4.7.5.2 The Objectives of System Restoration are the following: (i) to provide a general System Restoration strategy which will be adopted by the TSP in the event of a Partial or Total Shutdown of the Transmission System; (ii) to establish the responsibility of the TSP to produce and maintain a comprehensive System Restoration Plan, covering both Partial and Total Shutdowns; (iii) to establish the responsibility of Users to co-operate with the TSP in the development and execution of the System Restoration Plan; and (iv) to ensure that the TSP and User staff who will be potentially involved with the System Restoration Plan, should be adequately trained and fully familiar with the relevant details of the Plan. 4.7.5.3 During restoration process of the Transmission System, the normal standards of voltage and frequency shall not apply. 4.7.5.4 The TSP shall conduct drills, at least once each year, to train the Users for Emergency preparedness. The date and time of execution of such drills shall be agreed by the TSP with Users in advance and the TSP shall issue a Red Alert for such a drill. The Users must cooperate with the TSP for conducting such drills/testing. 4.7.5.5 Restoration Plan (i) The TSP shall issue instructions for the Generators with Black Start Capability to initiate the Start-up. The Generator providing Black Start shall then inform the TSP that its Generating Unit is dispatchable within thirty (30) minutes. (ii) Upon receipt of the instruction from the TSP, Generating Unit providing Black Start shall Start-up immediately to Energize a part of the System and/or Synchronize with the System. (iii) The overall strategy in restoring of the System after a Partial or Total Shutdown shall, in general, include the following: (a) overlapping phases of restoration of islanded parts of the System; (b) step-by-step integration of the islanded parts of the System into larger sections; and (c) eventual restoration of the whole System. Chapter 4 - Operating Code The Saudi Arabian Grid Code Updated Version: May 2024 (iv) The TSP shall coordinate the providing of Backup Reserve by thermal Generating Units so that these can be put back to the Grid without going to the full restart procedure. (v) The TSP shall inform the Users, after completing the System Restoration procedure and the restoration of the System, that the Blackout no longer exists and that the System is back to the normal state. (vi) The TSP will coordinate with Generators to provide power, first to auxiliary load of NPPs, and then start up Power (not reserve) to steam Units/Plants. 4.7.5.6 Resynchronization of Islanded Parts of The Grid (i) When parts of the System are not Synchronized with each other, the TSP shall instruct Users to regulate Generation and/or Demand to re- Synchronize the islanded parts of the System. (ii) If a part of the System is not connected to the rest of the System, but there is no Blackout in that part, the TSP shall undertake the re- Synchronization/reconnection of that part to the rest of the System. Operational Testing