What Are The Maintenance And Upkeep Procedures For Prefabricated Substations?

The maintenance and upkeep of prefabricated substations mainly includes four categories: daily inspections, periodic maintenance, preventative testing, and safety protection. These aim to ensure the long-term safe, stable, and efficient operation of the equipment and extend its service life.

 

Daily Inspections (Recommended at least once a month) This involves promptly identifying abnormalities through visual inspection, sound checks, and temperature measurements to ensure normal operating conditions.

Equipment Appearance Inspection: Check for deformation, rust, and aging of the sealing strips in the enclosure to prevent rainwater infiltration.

Operating Parameter Monitoring: Check if the voltage, current, power factor, and other instrument readings are normal.

Temperature Detection: Use an infrared thermometer to check high-voltage connectors, transformer casing, cable terminals, etc. Temperature rise should not exceed allowable values.

Sound and Odor Judgment: Listen for abnormal humming or discharge sounds from the transformer and smell for any burnt insulation odor.

Environmental Inspection: Confirm that there is no debris piled up around the area, ventilation openings are not blocked, and there are no signs of small animal activity.

 

Regular Maintenance (Performed on a Cycle-Based Approach)

Table: Maintenance Item | Cycle | Specific Content

Dust Removal & Cleaning: Once a year. Wipe the high and low voltage cabinets with a damp cloth. Clean the transformer room with air or a vacuum cleaner.

Terminal Tightening: Once a year. Due to thermal expansion and contraction, all terminal blocks need to be retightened (power off operation).

Lubrication & Maintenance: Once a year. Apply lithium-based grease to the switching mechanism and mechanical interlocking components to ensure smooth operation.

Silicone Replacement: Replace the silica gel desiccant in the breather as needed to prevent moisture from entering the transformer oil system.

Battery Inspection: Regularly check the voltage, internal resistance, and charge/discharge performance of the DC system batteries to ensure reliable power supply to the secondary system.

 

Preventive Testing and Professional Inspection

Insulation Resistance Testing: Regularly perform insulation tests on cables, surge arresters, and busbars to prevent leakage or breakdown.

Live Temperature Measurement: Use an infrared thermal imager to periodically measure the temperature of key contacts to identify potential overheating points.

Oil Sample Analysis: Take oil samples from operating transformers annually for chromatographic analysis to determine if there are internal partial discharge or overheating faults.

Protection Device Verification: Verify the relay protection... The protective device undergoes functional testing to ensure accurate and reliable operation.

 

Safety Protection and Precautions

Grounding System Inspection: The enclosure and grounding grid should have at least two reliable connections, with a grounding resistance of less than 4Ω.

Anti-Animal Measures: Seal cable inlets and outlets, install rodent barriers to prevent rodents and snakes from entering and causing short circuits.

Fire and Explosion Prevention Management: Equip with fire extinguishers; hot work is strictly prohibited near the transformer.

Operating Procedures: During maintenance, power must be turned off, voltage tested, and grounding wire installed. A "Do Not Close" warning sign must be displayed, and the "two-ticket, three-system" procedure must be strictly followed.