Saudi Arabian Grid Code May 2024

Voltage Control 4.4.4.1 To maintain Transmission System Security and integrity, to avoid damage to the Transmission System and to User Plant, and to maintain voltages at User Connection Points within the limits specified in Chapter 2: Connection Code, the TSP shall exercise control of the Transmission System voltages. 4.4.4.2 The TSP shall strive to maintain sufficient availability of dynamic and static Reactive Power capability in order to maintain Transmission System voltages at Connection Points within the levels specified in (2.4.3) of Chapter 2: Connection Code, at all times by means of one or more of the following measures: (i) the charging capacitance of the Transmission System; (ii) User Mvar Demand; (iii) Transmission System Mvar losses; (iv) Generating Unit Mvar production or absorption; (v) through on-load tap changing of Generating Unit step-up transformer; (vi) Voltage Control facilities, such as capacitor banks and reactors; and (vii) dynamic voltage support. 4.4.4.3 Voltage Control Policy The TSP shall control System voltage to minimize system losses and cost of System Services. The TSP shall determine and modify, as appropriate, general procedures for use in controlling voltage on the Transmission System. These procedures shall be formulated with due regard to minimizing cost of the Transmission System operation and optimizing System Safety and Chapter 4 - Operating Code The Saudi Arabian Grid Code Updated Version: May 2024 Reliability. In particular, the Voltage Control shall take cognizance of the daily, weekly and seasonal factors, and the TSP shall determine: (i) suitable target voltages in order to limit/control the effect of Transmission capacitance; (ii) best utilization of dedicated Voltage Control facilities; and (iii) Mvar dynamic reserve requirements. 4.4.4.4 Voltage Control Methods (i) The TSP shall continuously monitor the Transmission System voltages. Appropriate voltage monitoring points shall be determined by the TSP, taking account of the Voltage Control policy and in particular of the Transmission System conditions pertaining at the time of operation. (ii) The TSP shall adjust Transmission System voltages, using control facilities that are available so as to achieve the Mvar Capacity necessary in order to operate the Transmission System voltages at Connection Points within the levels specified in (2.4.3) and retain a dynamic Mvar capability to deal with changing System conditions which result from changes in Demand or changes in Transmission or Generation configuration, whether as a result of Control Actions or Faults. (iii) The Excitation System of each Synchronous Generating Unit shall be operated under the control of a continuously acting Automatic Voltage Regulator (AVR), which shall be set so as to maintain a constant terminal voltage. The Generator may not disable or restrict the operation of the AVR except in accordance with (iv) below, in which event the Generator shall notify the TSP immediately. The Automatic Voltage and Reactive Power Regulator System of each Power Park Module shall be operated under the control mode and with the set point agreed with the TSP (according to Ch. 2). The Generator may not disable or restrict the operation of the Automatic Voltage and Reactive Power Regulator Systems except in accordance with (iv) below, in which event the Generator shall notify the TSP immediately. (iv) The Generator may only disable or restrict the AVR action where: