RZA LLC has successfully installed the Transformer Depressurization System (TDS) developed by SERGI Ltd. on ten 220/35 kV power transformers at the Oyu Tolgoi mining site.

This system is designed to protect high-voltage power equipment from transformer explosions and significantly enhances operational safety, contributing to the reliable performance of mining operations.

Overview of the System

The Transformer Depressurization System (TDS) is a safety solution designed to mitigate the risk of transformer explosions and fire caused by sudden internal pressure build-up.

In cases such as internal short circuits or insulation failures, transformer oil may rapidly overheat, causing a sudden pressure increase that can lead to tank rupture or explosion. The TDS system detects this process within milliseconds and safely releases pressure to prevent catastrophic failure.

Operating Principle

• Overpressure detection:

  Sensors are activated when internal pressure rises rapidly above approximately 0.2–0.5 bar

• Response time:

  The system initiates operation within approximately 2–10 milliseconds

• Pressure relief mechanism:

  A fast-acting valve opens to safely discharge the oil and gas mixture

• Fire prevention:

  In some cases, oil is directed into a dedicated oil segregation tank to prevent contact with air and reduce fire risk