DIGITAL DIRECT-CURRENT DRIVE INCORPORATING DOUBLE PULSE-WIDTH MODULATION PROVISION Russian patent published in 1995 - IPC

FIELD: aerospace vehicles. SUBSTANCE: master device of drive is digital speed-setting unit 17 connected to first inputs of code commutator 20 and, through code converter 18, to second inputs of commutator 20. Digital code appears periodically across outputs of commutator 20 depending on voltage control pulses of low-frequency generator 19 arriving at output either from first or second inputs of commutator 20. Digital code picked off output of commutator 20 is applied to first inputs of control pulse shaper 25; control-pulse frequency is set by high-frequency generator 24. Control pulses arriving from forward and inverter outputs of shaper 25 go through logic unit shaping time delay to prevent throughput currents of transistor switches and reach bridge-type power amplifier. Motor 1 is controlled by high- and low- frequency pulses coming from generators 24 and 19, respectively, that is, it depends for its operation on double pulse-width modulation principle. EFFECT: provision for accurate and stepless control of direct-current motor. 10 dwg