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Two-frequency two-cascade converter for induction heater. RU patent 2405286.

FIELD: electrical engineering.

SUBSTANCE: proposed device comprises four controlled gates-thyristors, 1^st and 2^nd of which makes first cascade, and have their first outputs connected via 1^st input throttle with 1^st pole of constant voltage source, while 3^rd and 4^th controlled gates that make second cascade have their output connected via 2^nd input throttle with 2^nd pole of said power supply. Note here that inductor, an active inductive load, and 1^st switching capacitor are connected in parallel to second outputs of 1^st and 2^nd controlled gates. Besides 1^st and 2^nd tuned throttles have their outputs connected to extreme output of aforesaid inductor, second outputs of said throttles being connected to first outputs of 3^rd and 4^th controlled gates. Note here that 2^nd switching throttle is connected to the same points.

EFFECT: simultaneous generation of HF and LF electromagnetic fields, simplified circuitry.

5 dwg

IPC classes for russian patent Two-frequency two-cascade converter for induction heater. RU patent 2405286. (RU 2405286):

H05B6/04 - Sources of current

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Double-frequency two-step single- to three-phase converter for induction heating and fusion of metals / 2403688
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