Born Oct. 27, 1854, in the village of Bács, Hungary ; died Mar. 3, 1938, in Merano, Italy. Hungarian electrical engineer. Graduated from the Vienna Polytechnic Institute in 1877.
In 1883, Déri built a single-phase generator with self-excitation from a mechanical rectifier on the generator shaft. In 1885, together with K. Zipernovsky, he proposed a circuit for the distribution of alternating current by means of parallel connection of the primary windings of induction devices. In 1904 he invented a collector repulsion electric motor, which was named after him.