Abstract Method and apparatus for dynamically braking a multiphase motor wherein, in a first embodiment, the stator windings of the motor are connected in a six winding delta configuration and direct braking current is applied between two center taps of the configuration. A damping diode is connected across two of the delta center taps to minimize voltage transients in the windings when the direct current is removed. In a second embodiment, the stator windings are connected in a twisted Y--Y configuration, the connections to the neutral points of the two Y's of one phase winding set being interchanged and direct braking current being introduced between the two neutral points. A damping diode is connected between the center points of each Y to minimize voltage transients in the windings when the direct current is removed.
Apparatus for dynamically braking a motor operable from a source of three-phase current comprising: a motor stator section whose windings are connected in a delta configuration, each side of the delta comprising at least two windings connected at a center tap, said three-phase current being applied to the delta terminal points, a source of d.c. current, and switch means for connecting said source of d.c. current between two of said center taps of said delta configuration when the three-phase current source is removed from the delta terminal points whereby said motor is dynamically braked.
Claim 2
Dependent Claim
94 words
Apparatus for dynamically braking a motor operable from a source of three-phase current comprising: a motor stator section whose windings are connected in a delta configuration, each side of the delta comprising at least two windings connected at a center tap, said three-phase current being applied to the delta terminal points, a source of d.c. current, and switch means for connecting said source of d.c. current between two of said center taps of said delta configuration when the three-phase current source is removed from the delta terminal points whereby said motor is dynamically braked.
Claim 3
Dependent Claim
36 words
The apparatus as defined in claim 1 further including means connected between said two center taps for minimizing voltage transients in the windings when said source of d.c. current is removed from said delta center taps.
Claim 4
Dependent Claim
14 words
The apparatus as defined in claim 2 wherein said minimizing means comprises a diode.
Claim 5
Dependent Claim
47 words
The apparatus as defined in claim 1 wherein said motor drives a shaft upon which a plurality of magnetic disk units are disposed in a space stacked arrangement for rotation in planes parallel to one another, said disks being secured on said shaft as a unitary assembly.