FREQUENCY CHANGER Russian patent published in 1997 - IPC

FIELD: electrical engineering. SUBSTANCE: frequency changer has transformer whose magnetic circuit has N=2k+1 cores, where k is 1,2,3..., made of same magnetic material with rectangular hysteresis loop, each core being wound with different number of turns of primary winding W_1k connected in series opposition, where k is core number according to expression ζ_kW_1k= ζ_k+1•W_1k+1, where ζ_k is cross-sectional area of k-th core; W_1k is number of primary turns wounds on k-th core; each core is wound with different number of turns of secondary winding W_2k connected in series accordance according to expression ζ_k•W_2k= ζ_k+1•W_2k+1; each core, except for last one, carries two isolating windings whose terminal leads are connected through base resistors to emitter-base junctions of isolating transistors and form bidirectional switch; transistors are interconnected so that emitter of each transistor is connected through anode-cathode to collector of other transistor, and collectors of both transistors are connected simultaneously to terminal leads of secondary winding of respective k+1 core. This makes it possible to sequentially reverse polarity of same-type cores of magnetic circuit in predetermined sequence and to shape voltage pulses in secondary windings equal in amplitude, opposite in polarity, and shifted through angle Φ_k+1= K•π/N apart, where N is total number of cores in magnetic circuit both under open-circuit and load conditions. EFFECT: improved design, enlarged functional capabilities. 4 dwg