Regenerative motor control having field and armature coordinating means

Claim 1

A regenerative motor control for regulating the operative condition of a direct current motor from a power source between the motoring and regenerative states in accordance with a bi-polarity operative condition error signal produced by a motor operative condition error signal source, said control comprising: input amplifier means having an input couplable to the error signal source and an output providing a bi-polarity output signal; field circuit means having an input coupled to said input amplifier and an output connectable to the field winding of the motor, said field circuit means being responsive to said output signal for providing current energization in either direction through the motor field winding and for reversing the current energization from a first direction through zero to a second direction during a transient period initiated by a reversal of the polarity of the error signal; signal means connected to said field circuit means for providing a signal proportional in magnitude to the magnitude of the motor field winding current energization and having a polarity indicative of the direction of said energization; limiting means having an input receiving the signal from said signal means and an output connected to said input amplifier for limiting the output signal of said amplifier in accordance with the magnitude and polarity of the signal from said signal means to restrict the magnitude of the output signal in the initial portion of the transient period and under weak field conditions; an armature circuit means having an output connectable to the armature winding of the motor for energizing the armature winding responsive to the magnitude of the controlling signal of a preselected polarity applied to an input thereof, the energization of the armature winding providing motoring operation to the motor for one direction of field winding current energization and providing regenerative operation to the motor, for the motoring direction of motor rotation, for the other direction of field winding current energization; and circuitry having an output connected to said armature circuit means and an input connected to said input amplifier for providing a controlling signal of the preselected polarity to the armature circuit means from the bipolarity signal of the input amplifier.