How to design the power transmission network to ensure that the system can still operate normally when a single point failure occurs?

Designing the power transmission network to ensure that the system can still operate normally when a single point failure occurs is the key to ensuring the stability and reliability of the power system. Here are some methods and strategies to help the power system maintain normal operation when a single point failure occurs:

1. Ring network and mesh design
Ring network: Design the power transmission line into a ring structure to ensure that each node has a bidirectional power supply path. When a certain line or equipment fails, power can continue to be supplied through the reverse path.

Mesh design (Mesh Network): A grid is formed by multiple interconnected transmission lines, so that each node has multiple paths to choose from, further improving the redundancy and flexibility of the system.

2. Dual power supply
Dual power supply design: Critical loads (such as hospitals, data centers, etc.) use dual power supply from different substations or lines to ensure that when one line fails, the other line can continue to supply power.

3. Use backup substations and transformers
Backup substations: Set up backup substations at important nodes so that they can be switched when the main substation fails.

Redundant transformers: Backup transformers are configured in substations to support rapid switching and replacement of faulty transformers.

4. Automated protection and control systems
Automated protection devices: Automated relay protection devices are configured to quickly detect and isolate fault areas to prevent fault expansion.

SCADA system: Supervisory control and data acquisition system (SCADA) is used to monitor and control the power system in real time and respond to faults quickly.

5. Dynamic line capacity increase and intelligent switching
Dynamic line capacity increase (Dynamic Line Rating): Dynamically adjust the load capacity of the line according to real-time environmental conditions (such as temperature and wind speed) to improve transmission efficiency and response capabilities.

Intelligent switching technology: Using intelligent switching devices, the current path can be intelligently adjusted according to real-time load and fault status.

6. Distributed energy and microgrids
Distributed energy: Integrate distributed energy (such as solar energy and wind energy) into the power grid to provide support in the event of local faults.

Microgrid: Design and deploy small power grids that can operate independently. When a large power grid fails, it can be decoupled from the main grid and operate independently to ensure power supply in local areas.

7. Regular maintenance and monitoring
Line monitoring: Use sensors and monitoring equipment to monitor transmission lines in real time and identify potential faults in advance.

Regular maintenance: Regularly inspect and maintain transmission facilities to ensure that equipment is in optimal operating condition and reduce the probability of failure.

Through the above methods, the power transmission network can be designed to maximize its reliability and fault resistance. This design can not only effectively deal with single point failures, but also improve the overall efficiency and safety of the power system. Using modern technologies such as smart grids and automation systems, the resilience and adaptability of the power transmission network can be significantly enhanced.