可再生能源的电网整合技术简介（英文版）_34页_998kb

Renewable Energy Integration in Power Grids Summary

Core Content

The integration of renewable energy (RE) into power grids is becoming increasingly critical as the share of renewables in power generation continues to rise globally. This transition requires rethinking the design, operation, and planning of power systems to accommodate the unique characteristics of variable renewable energy (VRE), such as wind and solar power. These technologies are non-dispatchable, meaning their electricity output depends on environmental conditions and time of day, which introduces variability, uncertainty, location-specific properties, and low marginal costs.

Main Views and Key Information

1. Renewable Energy Classification

• Dispatchable Renewables: Hydro, geothermal, biomass, and others that can be controlled and are available on demand.
• Variable Renewable Energy (VRE): Wind and solar PV, which are intermittent and depend on meteorological conditions.

2. Challenges of VRE Integration

• Variability and Uncertainty: Require flexible grid management and reserve capacity.
• Location-Specific Properties: Need grid infrastructure tailored to the geographical distribution of resources.
• Low Marginal Costs: Present economic opportunities but also require careful cost assessment.

3. Technological Options for Integration

• Smart Grid Technologies: Enable bi-directional energy flow, improve grid reliability, and support real-time monitoring and control.
• Flexible Generation: Adjust the energy mix to optimize dispatchable and VRE sources.
• Energy Storage: Addresses short- and long-term variability through technologies like batteries, pumped-storage hydro, and hydrogen conversion.
• Grid Extension and Interconnection: Facilitates regional and international energy sharing, improving system flexibility and stability.

4. Economic and Regulatory Considerations

• Integration Costs: Include grid infrastructure and system operation costs, with the latter being the most significant (up to 30–40% of total costs).
• Policy and Market Design: Should support new business models, ancillary services, and price signals to incentivize VRE integration.

5. Case Studies and Applications

• Jeju Island, South Korea: A successful example of integrating VRE and smart grid technologies.
• Small Islands: Have demonstrated high VRE integration (up to 50%) due to limited grid flexibility and high costs of fossil fuel-based generation.

Key Benefits of VRE Integration

• Environmental and Social Benefits: Include reduced greenhouse gas emissions and improved energy security.
• System Efficiency: Through demand-side management and smart grid technologies, peak loads can be reduced, and grid losses minimized.
• Economic Opportunities: Especially in markets with high generation costs, VRE and storage technologies offer cost-effective solutions.

Technical Considerations

• Voltage Stability: VRE integration can cause voltage fluctuations, requiring advanced control mechanisms and reactive power management.
• Fault Ride-Through (FRT): Generation plants must remain connected during short-term grid disturbances to maintain stability.
• Protection Systems: Need to be adapted to account for distributed generation, including new relay designs and directional protection algorithms.

Communication and Standards

• ICT Integration: Essential for smart grids to enable real-time monitoring and control.
• IEC 61850 Standard: Facilitates interoperability between different grid systems and devices, though it does not cover market operations.

Energy Storage Technologies

• Pumped-Storage Hydro: The only commercial option for large-scale storage, though limited by geographical constraints.
• Battery Storage: Includes lead-acid, lithium-based, and flow batteries, with increasing applications in residential and off-grid systems.
• Other Options: Compressed air, flywheels, superconducting magnets, and chemical storage (e.g., hydrogen) are also under development.

Grid Interconnection

• Regional and International Interconnection: Enhances flexibility, reduces reserve requirements, and improves congestion management.
• HVDC Transmission Lines: Efficient for long-distance power transfer but require significant investment and time to implement.

Conclusion

Renewable energy integration into power grids is a complex process requiring technical, economic, and regulatory adaptations. Smart grid technologies, energy storage, and improved interconnection are key enablers for this transition. Policy makers must develop long-term frameworks that encourage innovation, ensure grid flexibility, and quantify both economic and non-economic benefits to support a sustainable and resilient power system.