Forced Oil Circulation Air Cooler for Transformer

Forced Oil Circulation Air-Cooled Transformer Oil Cooler

The ODWF system primarily consists of four key components that work together to complete the heat dissipation cycle:

Cooler Body: Contains multiple finned tube heat exchangers, serving as the core area for oil-to-air heat exchange. The fin design significantly increases the air contact surface area.

Forced Oil Pump: Installed within the oil circulation pipeline, it actively pumps heated oil from the bottom of the transformer tank into the cooler body, replacing natural convection to accelerate oil flow velocity.

Forced Air Blower: Uniformly arranged on both sides or the top of the cooler body, it generates a strong airflow that blows over the finned tubes, rapidly dissipating the heat transferred from the hot oil within the tubes to the fins.

Control System: Continuously monitors transformer oil temperature, oil flow velocity, and fan/pump status. Automatically activates or deactivates fans/pumps based on oil temperature (e.g., activates one set at ≥65°C, two sets at ≥75°C), enabling demand-based cooling.

The complete operational workflow comprises three steps:

Step 1: Hot Oil Delivery. The oil pump pressurizes high-temperature oil—which has absorbed heat from the core and windings—from the tank and feeds it into the heat exchange tubes of the cooler.

Step 2: Heat Exchange. As the high-temperature oil flows through the tubes, it transfers heat to the exterior via the tube walls and fins. Simultaneously, the powerful airflow generated by the fan blows transversely across the fins, rapidly dissipating heat and lowering the oil temperature within the tubes.

Step 3: Cold Oil Return. The cooled oil exits the other end of the cooler and returns to the transformer tank via the return oil line, where it reabsorbs heat, completing one cycle.

Core Advantages and Applicable Scenarios

Advantage 1: Exceptionally High Heat Exchange Efficiency: Compared to natural cooling (ONAN), heat exchange efficiency increases by 3-5 times; compared to single forced oil circulation (ODAF), efficiency further improves by 40%-60% due to the addition of forced airflow.

Advantage 2: Adaptability to High Loads and Harsh Environments: Even during prolonged full-load operation or installation in high-temperature (e.g., outdoor summer) or high-altitude (thin air) conditions, oil temperature remains stably controlled within safe limits (typically ≤85°C).

Advantage 3: Flexible and Controllable Operation: Supports parallel connection of multiple cooler sets (e.g., 6 or 8 sets), automatically adjusting the number of active sets based on load and oil temperature to balance heat dissipation needs with energy efficiency.

Typical application scenarios include:

Large power transformers with capacity ≥63,000 kVA (e.g., main transformers in 110kV, 220kV substations).

Industrial transformers operating at full load for extended periods (e.g., large production transformers in steel and chemical industries).

Outdoor transformers installed in high-temperature, high-humidity, or dusty environments.