OLTC Oil Immersed Power Transformer

As a professional high quality JUCEG OLTC Oil Immersed Power Transformer manufacturer,we will offer you the best after-sale service.OLTC enables the transformer to change the tap position while under load, thereby adjusting the output voltage. This is particularly important in situations requiring a stable voltage supply, such as areas with significant voltage fluctuations in the power grid or industrial scenarios with frequent load changes. OLTC Oil Immersed Power Transformer uses transformer oil as the insulating medium, which has high insulation strength and can effectively isolate the voltages between windings and between windings and the grounded iron core/oil tank, preventing short-circuit discharge. Transformer oil not only serves as an insulating medium but also plays a role in heat dissipation. It absorbs the heat generated during the operation of the transformer, transfers the heat through convection to the oil tank wall, and then dissipates it to the air through the oil tank wall, ensuring that the temperature of the transformer remains within the allowable range. The iron core is usually made of silicon steel sheets stacked together to reduce eddy current losses and magnetic hysteresis losses; the windings are made of copper or aluminum wires wound, divided into high-voltage windings and low-voltage windings, and convert the input electrical energy into different voltage levels of output electrical energy through electromagnetic induction.

How OLTC Transformers Work in Practice

Principle of Operation

An OLTC works by switching between tappings connected to different points on the transformer winding.

During each tap change:

1. The load current is temporarily transferred through transition resistors or reactors.

2. Arcing is controlled within an insulated switching chamber.

3. The output voltage is adjusted without interrupting supply.

This controlled process ensures stable voltage regulation even during heavy load changes.

Typical Voltage Control Range

Most OLTC transformers offer:

· ±10% voltage regulation

· Step sizes of 1.25% or 1.5%

· 17 to 33 tap positions depending on transformer design

OLTC Oil Immersed Power Transformer’These parameters are selected based on network planning studies and expected voltage drop along transmission or distribution lines.

OLTC in High Voltage and Electric Power Networks

OLTC transformers are widely deployed in:

· Transmission substations (110kV–765kV)

· Interconnection points between generation and load centers

· Industrial plants with fluctuating demand

· Grid tie transformers for renewable energy

In these electrical systems, OLTC Oil Immersed Power Transformer help stabilize voltage, reduce technical losses, and ensure compliance with utility voltage limits.

Application scenario

In the transmission and distribution networks, OLTC oil-immersed power transformers are used to regulate voltage and ensure the quality of electrical energy. Especially in long-distance power transmission or areas with significant voltage fluctuations in the power grid, their voltage regulation function is particularly important. They are suitable for industrial manufacturing sites that require stable voltage supply, such as the steel, chemical, and paper industries. The equipment in these industries has high requirements for voltage stability, and OLTC oil-immersed power transformers can meet their needs. In renewable energy systems such as solar and wind energy, OLTC Oil Immersed Power Transformer is used to synchronize the unstable power output with the power grid. It can help manage the unstable power output and ensure the interconnection of renewable energy systems with traditional power systems.