Saudi Arabian Grid Code May 2024

Voltage Withstand Capability Diagram 2.5.5.24 The Renewable Resource Generating Unit shall remain connected to the Network and continue stable operation if none of the phases exceeds 120% of nominal voltage for more than 1s. 2.5.5.25 Each Power Park Module which does not inherently provide short-circuit power and which has a Registered Capacity greater than twenty five (25) MW in aggregate, may be required by the TSP to provide dynamic voltage support during network disturbances. This dynamic voltage support is described by the following: i. The magnitude of the additional reactive current injection shall be determined as a linear function of the positive or negative voltage change (ΔU) with respect to the pre-disturbance value with total reactive current injection limited to 100% of rated current. ii. The dynamic voltage support shall not have priority over AVR and active power control of the generating units in the normal voltage range and in the 30-minutes range defined in (2.4.3). iii. The droop of this linear function shall be adjustable on request of the TSP from 0 additional reactive current injection (minimum droop) to an additional reactive current injection of 2% of the rated current per percent of the voltage drop (maximum droop). iv. If necessary, the active current shall be limited to enable dynamic voltage support. Time Voltage (p.u.) 1.3s 0.3s 30min SGU PPM Chapter 2 - Connection Code The Saudi Arabian Grid Code Updated Version: May 2024 v. In case of overvoltage, the additional reactive current shall have an inductive behavior and in case of undervoltage, the additional reactive current shall have a capacitive behavior. vi. The additional reactive current shall bring the total reactive current injection to at least 2/3 of the target value within 20ms (control response time) and this target value shall be reached with an accuracy of 10% within 60ms from the moment the voltage deviation occurs. vii. The dynamic voltage support shall be maintained for at least 400 ms after voltage recovery in the normal voltage range, or in the 30- minutes range defined in (2.4.3). viii. The transitions between dynamic voltage support and voltage control defined in 2.5.5.17 shall be smooth. ix. In case of unsymmetrical faults, the dynamic voltage support shall not escalate the overvoltages of the healthy phases above the maximum voltage defined in (2.4.3). 2.5.5.26 All Power Park Modules that remain synchronized to the network following a disturbance shall be able to recover Active Power output after fault clearance or after voltage regains levels specified in (2.4.3). The recovered Active Power output shall be higher than 90 % of the pre-fault value within 4 seconds after fault clearing unless prevented by the reduction of available active power. 2.5.5.27 Generating Units shall be capable of withstanding, without tripping, a negative phase sequence loading appropriate to their rated full load in accordance with the IEEE Standard C37.102-1995: IEEE Guide for AC Generator Protection. In addition they shall be required to withstand, without tripping, the negative phase sequence loading incurred by clearance of a close-up phase-to-phase Fault by backup Protection on the User System of which they are a part. 2.5.5.28 The higher voltage windings of the Generating Unit step-up transformer connecting the Generating Unit to the Transmission System must be star connected with the star point grounded in accordance with IEEE Standard C37.101-1993: IEEE Guide for Generator Ground Protection. If adjacent to a TSP Substation, it shall be connected to the Grounding System of that Substation. Chapter 2 - Connection Code The Saudi Arabian Grid Code Updated Version: May 2024 2.5.5.29 Generators will be responsible for protecting their Generating Units against the risk of any damage which might result from any frequency excursion outside the range 57.0 Hz to