Oil-immersed transformers have been widely used in various power distribution equipment. It is not difficult to observe in daily life that the most common and frequently used ones are oil-immersed transformers. They can be applied both indoors and outdoors and are relatively common power distribution components. Now, let's explore the composition of oil-immersed transformers from another perspective.
The core structure of an oil-immersed transformer consists of the transformer body, oil tank, cooling device, protective equipment, and outgoing line equipment. The transformer body includes the iron core, winding (coil), insulation, conductor, and tap changer; the oil tank includes the oil tank itself and oil tank accessories (oil drain valve, grounding screw, trolley, nameplate, etc.); the cooling device includes the radiator and cooling tower; the protective equipment includes the oil conservator, oil gauge, safety airway, moisture absorber, temperature measuring element, and gas relay; the outgoing line equipment includes high and low voltage bushings.
1. Iron core: The iron core is one of the most basic components of a transformer and constitutes the magnetic circuit part of the transformer. Both the primary and secondary windings of the transformer are wound on the iron core. To enhance the magnetic permeability of the magnetic circuit and reduce eddy current losses in the iron core, the iron core is typically made of 0.35mm silicon steel sheets with surface insulation. The iron core is divided into two parts: the iron core column and the iron yoke. The windings are arranged on the iron core column. The iron yoke connects to the iron core and functions to close the magnetic circuit. The iron core insulation of Minrong transformers is excellent, which goes without saying in factory evaluations and practical applications. This is related to the philosophy that Minrong Electric Group has always adhered to. It also focuses on Minrong Group's strong electrical technology and its conscientious approach to every process. The iron core of Minrong transformers serves as a high wall for electrical protection.
2. Winding (Coil): Winding is also one of the most basic components of a transformer. It is the circuit part of the transformer, generally made of copper or aluminum wire wrapped with insulating paper. The winding connected to the high-voltage grid is the high-voltage winding, and the winding connected to the low-voltage grid is the low-voltage winding. The role of the winding is to carry current, generate magnetic flux, and induce electromotive force. The winding is a key component of oil-immersed transformers, while Minrong transformers serve the industry with their high-quality, high-reputation windings, which has made Minrong Electric Group's position in the transformer industry increasingly solid.
3. Accessories: The accessories of a distribution transformer include an oil tank, an oil conservator, a tap changer, a safety vent, an insulating tube, etc. Their purpose is to ensure the safe and reliable operation of the transformer.
(1) Oil tank: The oil tank serves as the enclosure for the oil-immersed transformer. The transformer's iron core and windings are placed inside the oil tank, which is filled with transformer oil.
(2) Oil conservator (oil pillow): installed on the oil tank, providing protection for both the inside and outside of the tank.
(3) Safety vent (explosion-proof tube): installed on the top cover of the oil tank to protect the equipment and prevent damage to the oil tank due to malfunction. When a transformer malfunctions and produces a large amount of gas, the pressure inside the oil tank rises, and the gas and oil break through the explosion-proof membrane and spray outwards, preventing the oil tank from bursting.
(4) Gas relay (Buchholz relay): It is installed on the pipeline between the transformer oil tank and the oil conservator, serving as the main protective device. Inside, there is a float ball containing a mercury switch and a diaphragm used to activate the mercury switch. When a transformer experiences a fault, gas accumulates at the top of the gas relay, causing the oil level to decrease, the float to sink, and the mercury switch to be activated, sending a signal. In the event of a severe transformer fault, the oil flow breaks the diaphragm, causing it to deflect, which in turn activates a mechanism that opens another mercury switch, sending a signal and triggering a trip.
(5) Tap changer: In the power supply system, to maintain the transformer voltage within the permissible range, it is necessary to adjust the number of turns of the primary winding of the transformer within a certain range. Therefore, the primary winding generally has taps, which are called tap points. The switch can be connected to different connectors to change the number of turns of the original winding, achieving the effect of voltage regulation. Tap changers are divided into on-load tap changers and full-load tap changers.
Shenzhen Shentebian Electrical Equipment Co., Ltd. is a high-tech enterprise specializing in the research, development, and manufacturing of power transformers. Its main product line covers three categories: oil-immersed transformers, dry-type transformers, and prefabricated substations. As a professional manufacturer certified by the ISO9001 quality management system, the company produces various types of power transformation equipment that comply with IEC international standards and are widely used in urban and rural power grid construction, industrial power distribution systems, and new energy power generation fields.
