A transformer is a device used to convert AC voltage, current, and impedance. It operates based on the principle of electromagnetic induction and is a static electrical apparatus. Transformers come in many types, including pulse transformers, intermediate-frequency transformers, trigger transformers, shielding transformers, and more. Table of Contents Definition of a Transformer A transformer transfers electrical energy or signals from one circuit to another using the principle of electromagnetic induction. It is an essential component for electrical power conversion or signal transmission. A transformer consists of: Core (iron or magnetic core) Windings (two or more) The winding connected to the power supply is the primary winding, and the others are secondary windings. Working Principle of a Transformer A simple single-phase transformer consists of two conductive windings. When alternating current or pulsed DC flows through one winding, it generates a varying magnetic field, which induces a voltage in the second winding according to the principle of mutual induction. The voltage ratio between primary and secondary windings is proportional to their turns ratio: VsVp=NsNpfrac{V_s}{V_p} = frac{N_s}{N_p}Vp Vs =Np Ns Similarly, the current ratio is inversely proportional to the turns ratio. While transformers can step up or step down voltage, they do not amplify

With the rapid development of the global economy, dry-type transformers have experienced significant growth worldwide. In the field of distribution transformers in particular, the market share of dry-type units has been increasing year by year. In many countries, dry-type transformers now account for 40–50% of all distribution transformers. Table of Contents Structural Features of Dry-Type Transformers Safe, fire-resistant, and environmentally friendly, allowing installation and operation directly at load centers. Manufactured with advanced domestic technology, offering high mechanical strength, strong short-circuit resistance, low partial discharge, excellent thermal stability, high reliability, and long service life. Low loss, low noise, and significant energy-saving performance, with no need for maintenance. Excellent heat dissipation and strong overload capacity; capacity can be increased under forced-air cooling conditions. Superior moisture resistance, suitable for high-humidity or harsh environmental conditions. Can be equipped with a comprehensive temperature monitoring and protection system. The intelligent temperature control unit automatically detects and cyclically displays the operating temperature of each phase winding, and can automatically start/stop cooling fans while providing alarm and trip functions. Compact size, lightweight design, minimal footprint, and low installation cost. Structural Designs Open TypeA common structure where the transformer body is in direct contact with the atmosphere. Suitable for

Transformers are responsible for the efficient transmission and conversion of electrical energy, regulating voltage and minimizing power loss. Therefore, transformer design plays a critical role in ensuring system reliability and operational safety.This article provides a comprehensive explanation of transformer fundamentals — including basic structure, classifications, functions, selection criteria, design procedures, and typical applications. Table of Contents 1. What types of power transformers are there, and what are their main components? There are several types of power transformers, such as dry-type transformers, oil-immersed transformers, and pad-mounted distribution transformers.Their main components typically include: the core, windings, insulation system, tank (for oil-immersed types), cooling system, tap changer, bushings, and other protective accessories. 2.What Is Magnetizing Current (Excitation Current)? Magnetizing current is the excitation current needed to build magnetic flux inside the core.When a transformer is energized, a high inrush current may occur.If the residual flux has the same polarity as the applied voltage, the total flux can exceed core saturation, causing a surge up to 6–8 times the rated current.This transient current contains DC components and harmonics and decays over time, typically 5–10 seconds for large transformers and ~0.2 seconds for smaller units. 3.Why should a new transformer or an overhauled transformer receive