Electricity: motive power systems – Induction motor systems – Primary circuit control
Patent
1994-09-27
1997-03-04
Cabeca, John W.
Electricity: motive power systems
Induction motor systems
Primary circuit control
318800, 318804, 318808, 318723, H02P 534
Patent
active
056083025
ABSTRACT:
An apparatus for driving an AC motor at variable speeds facilitates arbitrary setting or adjustment of equivalent primary resistance of an AC motor. In one embodiment of the present invention, a reference AC voltage generator outputs reference AC voltage values for each phase of the AC motor, and signals derived from the reference voltage values are in turn used by a power converter to supply the AC motor with variable voltage and frequency. In this embodiment, two or more phase currents are fed back to, and subtracted from, the reference voltage values via a regulator. In another embodiment, an angular-frequency/biaxial-reference-voltage value generator generates a reference primary angular frequency value and biaxial reference voltage values of the AC motor in a rotating orthogonal coordinate system. In this embodiment, two or more of the AC motor's phase currents are fed back to, and subtracted from, the biaxial reference voltage values via a vector transformer and a regulator. The present invention not only avoids power loss associated with using resistors, but it also obviates manual, apparatus-by-apparatus adjustment of reference AC voltage values used to drive a given AC motor.
REFERENCES:
patent: 4361791 (1982-11-01), Plunkett
patent: 4394610 (1983-07-01), Dolland
patent: 4399395 (1983-08-01), Espelage
patent: 4555755 (1985-11-01), Kurosawa et al.
patent: 4585983 (1986-04-01), Cooper et al.
patent: 4825132 (1989-04-01), Gritter
patent: 5254926 (1993-10-01), Miller et al.
patent: 5329217 (1994-07-01), Kerkman et al.
"An Effective Method for Rotor Resistance Identification for High-Performance Induction Motor Vector Control" by Chan et al.; IEEE Transactions on Industrial Electronics and Control, vol. 37, No. 6, Dec. 1990, pp. 477-482, XP179409.
Cabeca John W.
Fuji Electric & Co., Ltd.
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