A MV-LV (Medium Voltage – Low Voltage) transformer is constructed with several key components. The main parts include the core, windings and insulation. The core is usually made of silicon-laminated steel sheets, which helps reduce energy losses due to eddy currents. The windings are made of copper or aluminum wire and are divided into high voltage (HV) and low voltage (LV) sections. The HV windings are placed on the inner part of the core, while the LV windings are on the outer part.
The assembly is then housed in a sturdy metal tank containing insulating oil, which contributes to cooling and insulation. The transformer is built to specific standards to ensure safety and efficiency of power distribution.
Transformers are mainly made from several materials. The core is usually made of laminated silicon steel to reduce eddy current losses. The windings are made of high-purity copper or aluminum wire, which conducts electricity efficiently.
Insulating materials such as paper, oil, or synthetic compounds are used to electrically insulate the windings and core from each other and from the tank. The outer casing of the transformer is usually made of steel or aluminum to protect the internal components and ensure structural integrity.
A MV-LV cabin is designed to house medium voltage (MV) and low voltage (LV) transformers in a secure and controlled environment. The construction of the cabin involves several stages. The cabin is usually made from sturdy materials such as steel or concrete to ensure durability and safety.
It includes compartments for transformers, switchgear and control equipment. The cabin is equipped with ventilation systems to ensure good cooling of the transformers and maintain optimal operating conditions. It also features safety measures such as fire protection systems, grounding and access controls to protect personnel and equipment.
To increase the secondary voltage of an MV-LV transformer, adjustments are usually made by changing the tap settings on the transformer tap changer.
The tap changer is a device that allows the number of turns in the windings to be varied, thereby adjusting the output voltage. This can be done manually or automatically, depending on the design of the transformer. It is crucial to ensure that the transformer and its associated equipment can handle the new voltage settings to avoid any damage or operational issues.
Resin transformers are made using a process called resin casting. The core and windings are first assembled in a mold.
Once assembled, the entire unit is wrapped in a resin material, which is usually a blend of epoxy or polyester resins. The resin is poured into the mold and allowed to harden, solidifying into a protective, insulating shell. This process provides excellent electrical insulation and protection against environmental factors such as humidity, dust and corrosive elements. The resulting transformer is compact, has high dielectric strength and is suitable for applications where space is limited or environmental conditions are harsh.