DEVICE FOR IMPROVING COMMUTATION OF DIRECT-CURRENT COMMUTATOR MACHINES Russian patent published in 2005 - IPC

FIELD: electrical engineering; improving commutation of dc commutator machines using any type of excitation.

SUBSTANCE: two radio signal sensors disposed near anode and cathode brush contacts respond to electromagnetic pulses caused by commutation processes and resonance-tuned circuits discriminate frequency band distinguished by highest correlation of these signals. Upon occurrence of arcing signals arrive at increment counter. Control unit functions to alternately connect outputs of radio signal sensors through analog multiplexer to insensitivity-threshold comparator whose output signal arrives at increment counter. Control unit reads out counter content in certain interval and clears it for new count implementing number-pulse conversion. The heavier the arcing, the greater number of pulses is accumulated by counter within preset time interval. Control unit reads out armature current through analog-to-digital converter thereby enabling computation of initial supply current through commutating poles. Then control unit computes averaged value of signals arriving from commutation sensors and current through commutating winding, its criterion being minimization of averaged values of signals coming from radio signal sensors. Commutating poles can be forced to improve dynamics in which case control unit checks up commutating pole current through analog-to-digital converter. In this way control system continuously computes supply current through commutating winding at which averaged feedback signal has minimal density and amplitude with respect to state of commutation from sensors.

EFFECT: enhance commutating ability of machine for different operating conditions and different condition of brush contact.

1 cl, 1 dwg