Assembly and commissioning of a 300 MVA, 18 kV / 400 kV step-up power transformer · Simón Bolívar Hydroelectric Plant (Guri)

• Scope of Service: Transformer assembly, bushing installation, radiator installation and high-vacuum dielectric oil treatment, together with diagnostic electrical test protocols, protection system functional testing and the final tests for start-up.

1. Executive Summary

Key Impact: Assured operational continuity of a critical 300 MVA asset responsible for transmitting power from the country's main hydroelectric source into the National Interconnected System, meeting the strictest international standards for insulation and conduction.

2. Technical Challenge (The Problem)

• Critical Context: The equipment serviced is a 300 MVA (18/400 kV) Efacec power transformer, a nerve centre for the stability of the National Electrical System (SEN). Any prolonged unavailability of this equipment compromises the power supply of a large part of the country.
• The Operational Challenge: Given the strategic importance of the equipment, the client required the work to be completed in record time (three weeks). This called for complex logistics to coordinate multiple work fronts running 24 hours a day, simultaneously and with no margin for error.

3. Comprehensive Solution (Engineering by CA Mantenimiento Eléctrico Costel)

CAMEC deployed a highly precise technical methodology to meet the manufacturer's standards:

• Specialized Diagnostics: Collection of baseline samples.
• Fluid Treatment: High-vacuum dielectric oil filling process, guaranteeing degassing and dehydration of the oil to prevent hot spots or insulation failure.
• Field Electrical Test Protocol:
• Megger (Insulation Resistance): Verification of the integrity of the solid insulation.
• TTR (Turns Ratio): Validation of winding polarity and turns ratio.
• Power Factor: Measurement of dielectric losses to confirm the purity of the insulation system.
• High-Performance Management: Deployment of 3 simultaneous work crews operating under coordinated planning to maximize hourly productivity.

4. Results and Value Metrics

• Immediate Availability: After completing the test protocols, the equipment was energized and commissioned with 100% success, operating entirely normally under load.
• Schedule Efficiency: The schedule was met within the timeframe the client wanted, minimizing the period of unavailability of the transformation unit.
• SEN Reliability: Stable power transmission from the Guri plant to the rest of the country was assured, mitigating the risk of catastrophic failure from faulty assembly and installation.

5. Asset Technical Data