Connecting solar power plants (PV plants) to the Saudi electricity grid involves adhering to technical standards and requirements to ensure network stability and safety. Here’s a comprehensive overview of the essential requirements for integration, as per the Saudi network code:
1. Frequency and Voltage Standards
The Saudi electrical grid operates on a primary frequency of 60 Hz. Solar power plants must handle frequency fluctuations within the range of 59.9 to 60.1 Hz during normal conditions, while also being able to accommodate wider variations in exceptional circumstances.
Voltage levels must remain within ±5% of nominal values, with allowances for temporary deviations of up to ±10%.
2. Reactive Power Control Requirements
Solar power units (Power Park Modules) must maintain reactive power at the connection point within the range of Q=[-0.33, 0.33] of the rated active power when operating above 20%. This helps in stabilizing the grid amid voltage fluctuations.
For output levels below 20%, the required reactive power range narrows to Q=[-0.05, 0.05]. The Transmission Service Provider (TSP) may adjust these requirements based on the Connection Agreement.
3. Protection Equipment and Schemes
Solar energy systems should employ effective isolation equipment at the Point of Connection (POC) to address short-circuit currents and faults. Protection systems must comply with defined fault clearance times, such as 80 milliseconds for 380 kV systems.
4. Harmonics and Flicker Management
The total harmonic distortion (THD) must not exceed 1.5%. Additionally, flicker severity at connection points should not surpass Pst = 0.8 and Plt = 0.6 over a weekly interval to avoid adverse impacts on grid stability.
5. Grounding and Short Circuit Requirements
Effective grounding is mandatory for voltages exceeding 110 kV. The maximum short circuit ratio at the connection point must be no less than 3.0 to ensure system stability during emergency disturbances.
Conclusion
These requirements play a crucial role in ensuring that solar power plants are safely and efficiently integrated into the Saudi electricity grid. Adhering to these standards helps maintain network stability and ensures the quality and reliability of power supply.
For further details, refer to the relevant Saudi electrical grid codes and standards.
Sourcing:
The Saudi Arabian Grid Code – Solar Power Plants