Introduction
Few inventions have shaped modern civilization as profoundly as the transformer. It enables electricity to travel hundreds of miles from power plants to homes and industries, making large-scale electrification possible. Yet the transformer’s journey from laboratory curiosity to grid essential spans more than a century and involves dozens of scientists across multiple continents. This article traces that remarkable history.
Part One: The Foundation—Faraday’s Discovery
The story begins in 1831 with Michael Faraday, a British scientist investigating the relationship between electricity and magnetism. On August 29 of that year, Faraday conducted a now-famous experiment: he wrapped two coils of insulated wire around opposite sides of an iron ring. When he connected one coil to a battery and observed the other with a galvanometer, he noticed a momentary current in the second coil each time he made or broke the connection .
This was the first demonstration of electromagnetic induction—the principle that a changing magnetic field can induce voltage in a nearby conductor. Faraday’s iron ring apparatus was, in essence, the world’s first transformer prototype . He reported his findings to the Royal Society on November 24, 1831, securing his place as the discoverer of electromagnetic induction and, by extension, the father of the transformer .
Interestingly, an American scientist named Joseph Henry had independently achieved similar results a year earlier, in 1830, at the Albany Academy. Henry’s experimental apparatus was actually closer to modern transformer designs. However, being a meticulous researcher, he delayed publication until 1832, by which time Faraday’s work was already public . The discovery thus bears Faraday’s name, though Henry’s contributions to electromagnetism remain significant .
Part Two: From Laboratory Curiosity to Practical Device
For decades after Faraday’s discovery, the “induction coil” remained primarily a laboratory instrument. German technician Heinrich Ruhmkorff improved the design significantly, producing high-performance induction coils and filing the first transformer patent in 1851 . His coils became the first transformers with practical utility, used for experiments and even medical treatments .
The true breakthrough came in the 1880s, when engineers began applying the principle to commercial power systems. In 1882, Frenchman Lucien Gaulard and Englishman John Dixon Gibbs filed a patent for an “induction coil” designed for electricity distribution, which they called a “secondary generator” . They demonstrated a 5 kVA unit at an exhibition in London in 1883 and, in 1884, transmitted 30 kW of power over 40 kilometers at the Turin International Exhibition in Italy .
Part Three: The Birth of the Modern Transformer
Gaulard and Gibbs’s design had limitations: it used an open iron core and connected the primary coils in series. Three young Hungarian engineers at the Ganz Works—Károly Zipernowsky, Miksa Déri, and Ottó Bláthy—recognized these shortcomings after visiting the Turin exhibition .
Working tirelessly, they developed a transformer with a closed iron core and parallel-connected primaries—fundamental features still used today . The Hungarian patent application was filed on August 7, 1884, describing this revolutionary closed-core design .
The world took notice on May 1, 1885, at the Budapest National Exhibition. A 150V, 70Hz single-phase alternator supplied power to 75 Ganz transformers (each 5 kVA), which stepped down the voltage to light 1,067 Edison lamps. The spectacular display demonstrated beyond doubt that alternating current, with efficient transformers, could rival and surpass direct current for distribution . This date is now celebrated as the birth of the practical, modern transformer .
It was also Bláthy who coined the term “transformer” in 1885, replacing earlier names like “induction coil” and “secondary generator”—a term so apt that it has been used universally ever since .
Part Four: The War of the Currents
The transformer’s emergence coincided with—and largely decided—the “War of the Currents” between Thomas Edison’s direct current (DC) system and George Westinghouse’s alternating current (AC) system, backed by Nikola Tesla’s inventions .
DC systems could not easily change voltage. Power plants had to be located every mile or so, and transmission losses were enormous. AC, with transformers, could step up to high voltages for long-distance transmission, then step down for safe use . Westinghouse, having purchased the American rights to the Gaulard-Gibbs transformer and Tesla’s AC motor, demonstrated the first AC transmission system in the United States on March 20, 1886, in Great Barrington, Massachusetts .
The transformer’s ability to efficiently change voltage gave AC the decisive advantage, establishing it as the global standard for electrical power distribution—a position it still holds today .
Part Five: The Chinese Transformer Industry
China’s transformer industry began in earnest after the founding of the People’s Republic. In 1952, the Shenyang Transformer Factory produced the country’s first domestically made large-capacity transformer—the “5000″—a 5,000 kVA unit that marked the end of China’s reliance on imported large transformers .
The 1980s saw another leap forward. Despite foreign skepticism, Chinese engineers developed 500 kV transformers, achieving breakthroughs that outperformed imported equivalents. One 360 MVA, 500 kV autotransformer for the Gezhouba Dam project entered service in 1986, while a competing Japanese unit later failed during testing .
In the new millennium, China reached the forefront of transformer technology. The 1,000 kV UHV AC pilot project, commissioned in January 2009, featured entirely domestically manufactured transformers—a milestone achieved by Shenbian and other Chinese manufacturers .
Conclusion
From Faraday’s simple iron ring to today’s 1,000 kV UHV giants, the transformer has evolved over nearly two centuries. It transformed electricity from a local curiosity into a global utility, settled the “War of the Currents,” and continues to enable the energy transition. The transformer’s history is, in many ways, the history of modern electrification itself.
Post time: Mar-23-2026