GB/T 42558.2-2024 in English

1. Standard Overview

GB/T 42558.2-2024 Earthquake-resistant Technology for Electrical Equipment of Converter Stations in Plateaus Part 2: Earthquake-resistant Design Code is a technical standard for the earthquake-resistant design of electrical equipment of converter stations in plateaus. This standard is applicable to converter stations with an altitude of 1000m to 5000m, a voltage level of ±400kV and above, and earthquake-prone areas with a fortification intensity of 6 to 9 degrees.

2. Core requirements and technical points

2.1 Basic requirements

• Scope of application:Altitude of 1000m to 5000m, voltage level of ±400kV and above.
• Fortification intensity:Earthquake-prone areas with a fortification intensity of 6 to 9 degrees.
• Seismic design objective: Ensure that the equipment is not damaged under earthquakes of the design intensity.

2.2 Seismic action and verification

The standard specifies the calculation method for seismic actions, including horizontal and vertical seismic actions. Specific requirements are as follows:

2.3 Equipment Classification and Anti-Seismic Measures

Equipment is divided into the following categories according to its anti-seismic performance:

• Pillar equipment:DC pillar insulators, bridge arm reactors, etc.
• Transformers and high-voltage shunt reactors:Converter transformers, flexible DC transformers, etc.
• Suspension equipment:Suspension converter valves, suspension insulators, etc.
• Long cantilever equipment:Wall bushings, converter transformer valve side bushings, etc.

3. Implementation suggestions and technical applications

3.1 Precautions in the design stage

• Seismic calculation:Use the vibration mode decomposition response spectrum method or time history analysis method.
• Power amplification factor:Depending on the voltage level, the value range is 1.2 to 2.0.
• Material selection:High damping and high strength materials are preferred.

3.2 Construction and installation requirements

• Foundation design:The foundation of the converter transformer should be pile foundation, and the concrete strength grade should not be lower than C25.
• Support selection:In areas with seismic fortification of 7 degrees or above, lattice steel supports are preferred.
• Soft conductor connection:Redundancy should be reserved for soft conductors between equipment, and the maximum pulling force should not exceed the bending bearing capacity.

3.3 Precautions during the operation and maintenance phase

• Regular inspection:Pay special attention to the connection parts of suspended equipment and pillar equipment.
• Monitoring system:Establish an earthquake monitoring system to monitor the equipment's operating status in real time.
• Maintenance records:Detailed records of the equipment's earthquake resistance performance and the impact of previous earthquakes.