METHOD FOR SMOOTH CONTROL OF ELECTRICAL INDUCTION MACHINE Russian patent published in 2002 - IPC

FIELD: induction-machine drives for various industries. SUBSTANCE: capacitive reactance is inserted in circuit incorporating induction machine connected to antiparallel semiconductor components controlled by applying control pulses to gate electrodes and their movement in vicinity of positive voltage half-waves across each of semiconductor components; control pulses are set in motion by semiconductor components within range extended towards advance through angle , where x_ecr and R_er are, respectively, inserted equivalent capacitive reactance and equivalent resistance of electrical machine. During machine starting control pulses are moved in direction causing reduction of turn-on angles of connection of semiconductor components and during its stopping control pulses are moved towards increasing these angles. Proposed circuit arrangement provides for correction of reactive power consumed by induction machine from supply mains, enhanced throughput active power of power supply system, and improved power characteristics of supply circuit during machine starting, full-load running, and stopping. EFFECT: enhanced efficiency and reduced power loss of machine. 6 cl, 5 dwg