Article 3 : The journey of the first Transformer

We all know, The transformer works on the principle of Faraday’s law of electromagnetic induction. But, how many of us know that it took 54 years to invent first transformer after the invention of Faraday’s law of electromagnetic induction. Let me share the information I have about that journey in brief.

Faraday's first experimental demonstration of electromagnetic induction was on August 29th, 1831. It contained two independent coils and a closed iron core i.e. all basic elements of transformers But after the long time in 1885 three young Hungarian engineers of the Ganz factory in Budapest, Karoly Zipernowsky, Miksa Deri, and Otto Blathy constructed the first transformer. Let’s see how the development occurred.

Faraday’s apparatus was designed to study whether a direct current (dc) and the magnetic field that was produced by a dc coil induced voltage in another coil. the apparatus was fed by a dc galvanic battery, since no other power source was available at that time.

In 1832, Joseph Henry noticed that due the rapid flux changes several hundred volts voltage is induced in the coil, while the interruption of current. And thus self-inductance was invented.

In 1836, Callan made an inductor with iron core of ductile iron bar in which he led the intermittent current of the battery into a primary coil with low number of turns, while the secondary coil was made from thin wire, with high number of turns. In 1838, Page from America, and, in 1842, Masson from France were able to generate several kV with similar devices; voltage could spark over an air gap of several millimetres between the poles of the secondary coil. These were the first spark inductors.

When battery turned on, long time but low-amplitude half-wave is induced; when breaking it, short time, but high-peak voltage is induced. The first inductors only provided sparks that were a few millimetres long, but, in 1853, Daniel Ruhmkorff increased the spark length first to 200 mm then to 450 mm by improving the vibrator and the insulation.

Apps from England was able to produce 1,070 mm long sparks in 1876. The biggest inductor was constructed by Klingelfuss from Switzerland, his inductor that was presented at the World Exhibition in Paris in 1900 produced 1,500 mm long sparks.

Remember, at that time even flame-arc lamp was considered as the area of curiosity and those lamps were work on DC. In the 1870s, Jablochkoff made flame-arc lamp which worked on AC supply only.

As arc lamps spread, the need emerged that a generator should not only feed one lamp but all the lamps along an avenue. Because of the voltage drop of the lines, the distance between the generator and the flame-arc lamps cannot exceed 100-200 m in a parallel system. Supply voltage of 1,000-1,500 V can operate 20-30 lamps in a series connection, the line of lamps may be several km long.

Jablochkoff was the first who realized in Paris in 1877 that instead of their direct connection into the serial main line, lamps should be fed through a two-coil induction device. on the same line of theory?Lucien Gaulard and John Dixon Gibbs made secondary generator.They thought that the load change of the lamps fed by secondary generator, would not affect the current of the primary generator.Then they came to know that they were wrong.

Many people consider the secondary generator as the first version of the transformer. The major difference is that it had open iron core as Ruhmkorff inductor.The electric system that Edison built in New York in 1882 proved that wide-range public power supply can only be realized with permanent voltage network and the parallel arrangement of the consuming equipment. In 1885, Karoly Zipernowsky, Miksa Deri, and Otto Blathy introduce first transformer.

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The crucial step was taken in March 1885.

1.??????Rejecting series connection and connecting transformers that supply the consuming equipment groups in parallel to the main line

2.??????Applying high-ratio transformers, separating high-voltage (1400-2000 V) wide supply network from low-voltage (100 V) consumer networks

3.??????Developing a transformer with closed iron core, for low losses.

The invention of Zipernowsky and his colleagues is not the transformer or its connection alone, but the system as a whole. At the same time, they elaborated the shell-type and the core-type construction as well. The name transformer (“transzformator” in Hungarian) was also given by them.

The Ganz factory immediately started the series production of transformers. The thousands piece was manufactured in 1889, and the ten thousandth one in 1899. Since then, transformer has been the inevitable element of power system.?