Electricity: motive power systems – Motor-reversing – Armature or primary circuit control
Patent
1974-12-20
1977-02-01
Scott, James R.
Electricity: motive power systems
Motor-reversing
Armature or primary circuit control
318230, 318231, 318341, 318599, H02P 540
Patent
active
040063917
ABSTRACT:
A typical alternating current two phase servomotor has two windings displaced 90.degree.; these windings are normally identified as the reference winding and the control winding. Rotational direction and speed of the motor may be controlled by applying AC voltages of the proper waveform amplitude and phase relationship to these windings. When controlling the direction of rotation and speed of such alternating current servomotors in accordance with a DC error signal, pulse width modulation is utilized. The DC error signal is compared with a periodic varying function and its inverse to generate a series of pulses that are logically combined with a square wave and its complement during an enable period to generate a first and second series of pulses each having a width related to the magnitude of the error signal and coupled to energize the control winding of the alternating current servomotor. Similarly, a second periodic signal and its inverse are used to generate pulses for the reference winding. The second periodic signal is displaced 180.degree. in phase from the first periodic signal used for the control winding above. The DC error signal is compared with the second periodic function and its inverse to generate a second series of pulses each having a width related to the magnitude of the error signal. The second series of pulses is logically combined with a square wave and its complement during an enable period to produce output pulses to the reference winding. The motor energizing signals control a power switching amplifier connected to the respective windings of the motor to be controlled and responsive to the appropriate pulse width modulated signals.
REFERENCES:
patent: 3079539 (1963-02-01), Guerth
patent: 3181046 (1965-04-01), Sutton
patent: 3260912 (1966-07-01), Gregory
patent: 3278750 (1966-10-01), Eissfeldt
patent: 3286192 (1966-11-01), Collings et al.
patent: 3343055 (1967-09-01), Havlicek et al.
patent: 3396347 (1968-08-01), Richman et al.
patent: 3458789 (1969-07-01), Gray et al.
patent: 3538458 (1970-11-01), Lawson
patent: 3560829 (1971-02-01), Brennan
patent: 3700987 (1972-10-01), Deering
patent: 3717822 (1973-02-01), West
patent: 3760248 (1973-09-01), Nola et al.
patent: 3783408 (1974-01-01), Bird
patent: 3849709 (1974-11-01), Berman
Deering Charles S.
Redmond William G.
E-Systems Inc.
Feldhaus John J.
Scott James R.
Wilder Robert V.
LandOfFree
Linearized pulse width modulator does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Linearized pulse width modulator, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Linearized pulse width modulator will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1093258