THREE-PHASE TRANSFORMERLESS DIRECT FREQUENCY CONVERTER Russian patent published in 2021 - IPC H02M5/27 

FIELD: converter equipment.

SUBSTANCE: invention relates to converter equipment and can be used to power frequency-controlled alternate current (AC) electric drives. The converter contains three single-phase direct frequency converters (DFCs) having the same structure, each of which has twelve ADCs (1-12), twelve subtractors (13-24), eleven blocks for selecting the lowest voltage (BSLV) (25-35), thirteen logic elements AND (36-47, 102) a switch (48), a memory block (49), setting voltage amplitude (50) and frequency (51) registers, summing counters (52, 98, 99 and 100), a generator of stable pulses (53), logic elements OR (54 and 109), numerical comparators (55 and 101). BSLVs have the same structure, including a numerical comparator (56), n-bit electronic keys (57 and 58), short pulse shapers (59 and 60), a logic element OR (61), an RS trigger (62 and 103), a memory register (63). The switch (48) includes electronic keys (64-91), an RS-trigger (92), a pulse distributor (93). In addition, the converter contains the START bus (94), the output terminals of the converter (95 and 96). The common fragments (97) of the DFC circuits have differences in connection to the initial installation unit, which combines the second (98), third (99) and fourth (100) summing counters, a short pulse generator (104), a three-output pulse distributor (105), the bus (106) INSTALLATION. The pulse distributor (93) includes the logic elements AND (107 and 108) and OR (109).

EFFECT: expanding the functionality by increasing the number of controlled output information channels for supplying consumers with single-phase and three-phase current with specified parameters.

1 cl, 8 dwg