Dc motor speed control with motor voltage and current sensing means

Claim 2

A motor control circuit for energizing of a motor having an armature to maintain a regulated motor output, comprising command means to establish a command voltage signal proportional to a desired motor output signal forming means having means coupled to the motor to establish a first signal related to the actual motor output and the desired output to define an error signal and current sensing means to establish a second signal proportional to armature current, control means for controlling the input power connection of said motor to an incoming power supply, and actuating means for said control means connected to said signal forming means and having a first input means connected to receive said first signal and a second input connected to receive said second signal to produce a net signal equal to the sum of the error signal and the signal proportional to the counterelectromotive force and connected to said control means and actuating said control means in accordance with the summation of said first and second signals, said second signal being of a polarity corresponding to the armature voltage for establishing essentially zero power input to said motor with said actual motor output corresponding to said desired output and providing a continuous positive tracking of the counterelectromotive force of the armature.

Claim 3

A motor control circuit for energizing of a motor having an armature to maintain a regulated motor output, comprising command means to establish a command voltage signal proportional to a desired motor output signal forming means having means coupled to the motor to establish a first signal related to the actual motor output and the desired output to define an error signal and current sensing means to establish a second signal proportional to armature current, control means for controlling the input power connection of said motor to an incoming power supply, and actuating means for said control means connected to said signal forming means and having a first input means connected to receive said first signal and a second input connected to receive said second signal to produce a net signal equal to the sum of the error signal and the signal proportional to the counterelectromotive force and connected to said control means and actuating said control means in accordance with the summation of said first and second signals, said second signal being of a polarity corresponding to the armature voltage for establishing essentially zero power input to said motor with said actual motor output corresponding to said desired output and providing a continuous positive tracking of the counterelectromotive force of the armature.

Claim 4

A motor control circuit for energizing of a motor having an armature to maintain a regulated motor output, comprising command means to establish a command voltage signal proportional to a desired motor output signal forming means having means coupled to the motor to establish a first signal related to the actual motor output and the desired output to define an error signal and current sensing means to establish a second signal proportional to armature current, control means for controlling the input power connection of said motor to an incoming power supply, and actuating means for said control means connected to said signal forming means and having a first input means connected to receive said first signal and a second input connected to receive said second signal to produce a net signal equal to the sum of the error signal and the signal proportional to the counterelectromotive force and connected to said control means and actuating said control means in accordance with the summation of said first and second signals, said second signal being of a polarity corresponding to the armature voltage for establishing essentially zero power input to said motor with said actual motor output corresponding to said desired output and providing a continuous positive tracking of the counterelectromotive force of the armature.

Claim 5

In a motor control circuit for controlling the energization of a motor having an armature with an armature current varying with the motor load in accordance with a feedback signal, comprising means to supply current to the armature, a first feedback signal means providing a signal proportional to the actual motor output, a command signal unit, a first comparing means having a pair of input means connected to the first feedback signal means and to the command signal unit and establishing an error signal output proportional to the algebraic summation thereof, a second feedback signal means providing a corresponding current signal proportional to the motor armature current for all modes of motor operation and the related resistance armature voltage drop of the motor and a voltage signal proportional to the motor armature voltage, and a second comparing means having input means connected to said first comparing means and to the second feedback signal means and providing a summated error signal equal to the difference of the current signal and the voltage signal algebraically added to the error signal with the current signal polarity corresponding to the polarity of the first feedback signal means and connected to the means to supply current for controlling the current supply to the armature of said motor within the rating of the motor.

Claim 6

In a motor control circuit for controlling the energization of a motor having an armature with an armature current varying with the motor load in accordance with a feedback signal, comprising means to supply current to the armature, a first feedback signal means providing a signal proportional to the actual motor output, a command signal unit, a first comparing means having a pair of input means connected to the first feedback signal means and to the command signal unit and establishing an error signal output proportional to the algebraic summation thereof, a second feedback signal means providing a corresponding current signal proportional to the motor armature current for all modes of motor operation and the related resistance armature voltage drop of the motor and a voltage signal proportional to the motor armature voltage, and a second comparing means having input means connected to said first comparing means and to the second feedback signal means and providing a summated error signal equal to the difference of the current signal and the voltage signal algebraically added to the error signal with the current signal polarity corresponding to the polarity of the first feedback signal means and connected to the means to supply current for controlling the current supply to the armature of said motor within the rating of the motor.

Claim 7

In a motor control circuit for controlling the energization of a motor having an armature with an armature current varying with the motor load in accordance with a feedback signal, comprising a voltage source for energizing of said armature, a first voltage feedback signal means providing an armature voltage signal proportional to the armature voltage, a command signal unit establishing a voltage proportional to a desired armature voltage, a first comparing means having a pair of input means connected to the first voltage feedback signal means and to the command signal unit and establishing an error signal output proportional to the algebraic summation thereof, a second feedback signal means providing a corresponding current signal proportional to the motor armature current for all modes of motor operation and the related resistance armature voltage drop of the motor and establish an IR drop voltage signal proportional to the motor armature voltage drop, and a second comparing means having input means connected to the first and second feedback signal means and with the IR drop voltage signal subtracted from the armature voltage signal to provide a tracking signal proportional to the counterelectromotive force and connected to said first comparing means to add the error signal to the tracking signal and provide a summated error signal to the voltage source for continuously controlling the current supply to the armature of said motor within the rating of the motor.

Claim 8

In a motor control circuit for controlling the energization of a motor having an armature with an armature current varying with the motor load in accordance with a feedback signal, comprising a voltage source for energizing of said armature, a first voltage feedback signal means providing an armature voltage signal proportional to the armature voltage, a command signal unit establishing a voltage proportional to a desired armature voltage, a first comparing means having a pair of input means connected to the first voltage feedback signal means and to the command signal unit and establishing an error signal output proportional to the algebraic summation thereof, a second feedback signal means providing a corresponding current signal proportional to the motor armature current for all modes of motor operation and the related resistance armature voltage drop of the motor and establish an IR drop voltage signal proportional to the motor armature voltage drop, and a second comparing means having input means connected to the first and second feedback signal means and with the IR drop voltage signal subtracted from the armature voltage signal to provide a tracking signal proportional to the counterelectromotive force and connected to said first comparing means to add the error signal to the tracking signal and provide a summated error signal to the voltage source for continuously controlling the current supply to the armature of said motor within the rating of the motor.

Claim 9

The motor control circuit of claim 3 for controlling a reversible motor, having a pair of parallel connected gated rectifying networks connected to energize said motor, said second comparing means connected to said rectifying networks and said summated error signal controlling gating of said networks, said first comparing means establishing a direct current error signal output related to the relative polarities of the input and proportional to the algebraic summation thereof, and a selection means connected to first comparing means and said rectifying networks to enable one network in response to a given polarity of the error signal and the other network in response to an opposite polarity of the error signal.

Claim 10

The motor control circuit of claim 3 having an alternating current input means and a pair of gated networks connecting said alternating current input means to said motor, and a gating regulator connected to said second comparing means and to said gated networks and establishing a phased gating of said networks during each half cycle of the alternating current in accordance with said summated error signal.

Claim 11

The motor control circuit of claim 3 for controlling the power supplied to the armature of a direct current motor, having an alternating current input means and a pair of parallel rectifying gated networks connected in parallel to said input means and said motor armature and a gating regulator connected to said second comparing means and to both of said gated networks to simultaneously generate phase gate signals during each half cycle of the alternating current, and selection means responsive to said first named error signal and connected to said regulator to operatively inhibit one of said gate signals.

Claim 12

The motor control circuit of claim 3 having a polyphase alternating current input means, and a pair of gated networks each including a plurality of gate controlled rectifiers connected in phase related pairs, said networks being conneCted in parallel and polarized to conduct opposite load currents and connected between said input means and said motor, a gating regulator connected to said second comparing means and having a plurality of output means connected to said paired controlled rectifiers to control the firing thereof during each corresponding half cycle of the applied alternating current, said first comparing means establishing a direct current error signal output related to the relative polarities of the input and proportional to the algebraic summation thereof, and a selection means connected to first comparing means and said rectifying networks to enable one network in response to a given polarity of the error signal and the other network in response to an opposite polarity of the error signal.

Claim 13

The motor control circuit of claim 3 having an alternating current input means and a pair of gated unidirectional conductive networks connecting said input means to said motor, and a solid state logic circuit having an alternating current input phase related to the alternating current input to said gated network and having means to establish a series of time spaced pulses for gating said gated network at a given time in each half cycle, and circuit means connected to said logic circuit and to said second means to vary said given time and establish a zero current network output under all motor operation wherein said error signal is zero.

Claim 14

The motor control circuit of claim 3 having an alternating current input means, a pair of gated rectifier networks connecting said input means to said motor, and a solid state logic circuit having an alternating current input phase related to the alternating current input to said gated rectifier networks and having a pair of pulse generating channels including a common input to said second comparing means and each establishing a series of time spaced pulse trains for gating a corresponding network at a given time in each half cycle, and having corresponding pulses in said trains being spaced by 180* with respect to said input means, and circuit means connected to said logic circuit and to said second means to vary said given time and establish a zero network current under all motor operation wherein said error signal is zero.

Claim 15

The motor control circuit of claim 3 having an alternating current input means and a pair of gated networks connecting said input means to said motor, and a solid state logic circuit having an alternating current input phase related to the alternating current input to said gated networks and having means to establish a series of time spaced pulses for gating said networks in at a given time in each half cycle, and circuit means connected to said logic circuit and to said second means to vary said given time and establish a zero current under all motor operation wherein said error signal is zero.

Claim 16

The motor control circuit of claim 3 having an alternating current input means and a gated rectifying network connecting said input means to said motor, and a gating regulator having a binary logic output whereby a pulse is generated by successive timed changes in the output between two magnitudes, said gating regulator having a reference alternating current input having zero crossover points phase shifted 30* to lead the alternating current input to the gated network and constructed to generate a first edge of a pulse at each zero crossover point, a reference alternating current phase shifted to lag said alternating current input to said network by 60* and connected in said gating regulator to form the second edge of said pulse and to limit the firing during each half cycle to a given maximum output point, and a direct current bias signal source adapted to be connected to said gating regulator to establish an effective zero crossover point in phase with the zero crossover point of the alternating current input to the gated network in the absence of a summated error signal, and circuit means to connect The bias signal source and said second means to said gating regulator to establish a signal intercept with said reference alternating current input and thereby establish said first edge of the pulse in accordance with said bias signal and said summated signal.

Claim 17

The motor control circuit of claim 3 having a polyphase alternating current input means, a pair of similar gated rectifier networks connected in parallel to said input means and to said motor, and each having a pair of gated devices for each phase of said input means, and a gating regulator having a binary logic output channel for controlling a pair of gated devices for one phase of each network, each channel of said gating regulator having a zero detector and a first intercept detector for one network and a second intercept detector for the second network, a first reference alternating current input connected to said intercept detector and having zero crossover points phase shifted 30* to lead the alternating current input to the related pair of gated devices of said networks and constructed to generate a change in the logic level of the intercept detectors at each zero crossover point, a second reference alternating current phase shifted to lag said alternating current input to said network by 60* and connected to said zero detector to change the logic level to the zero detector at each zero crossover point, to limit the firing during each half cycle to a given maximum output point, and a direct current bias source connected to said intercept detectors to establish an effective zero crossover point in phase with the zero crossover point of the alternating current input to the gated network in the absence of a summated error, and circuit means to connect said second comparing means to said intercept detectors to establish a signal intercept with said reference alternating current input and thereby establish said change in logic level in accordance with said bias signal and said summated signal, first pulse means to control the first network and connected to said first intercept detector and said zero detector to establish a pulse signal during the positive half cycle of the second reference signal, second pulse means to control the second network and connected to said second intercept detector and said zero detector to establish a pulse signal during the negative half cycle of the second reference signal.

Claim 18

The motor control circuit of claim 12, having a gate means connecting said first pulse means to said first network and a second gate connecting said second pulse means to said second network, said first comparing means establishing a direct current output having a polarity related to the relative polarities and magnitudes of the inputs thereto, a polarity detection means connected to the output of the first comparing means and to said gate means to selectively enable one of said gate means in response to a first polarity and the other in response to the second polarity.

Claim 19

The motor control circuit of claim 12, wherein said intercept detectors include a load detector amplifier having an input means, said first reference alternating current being applied to said input means and biasing said amplifier to a first signal logic level during the positive half cycle and a second signal logic level during the negative half cycle, said direct current bias source being connected to said input means and biasing said amplifier to increase the period of one of said signal levels and decrease the period of the other of said signal levels, and said second comparing means being connected to said input means to vary the direct current bias to said input and thereby vary the intercept with said first reference alternating current to control the phase at which said signal logic level changes.

Claim 20

In a motor control circuit for a motor having an armature connected in an armature circuit to an alternating current supply, command means to establish a command voltage signal proportional to a desirEd motor operation, first voltage feedback means to establish a feedback signal proportional to the armature voltage, first summating means connected to said command means and to said feedback means to provide an error voltage signal, second feedback means having a first current sensing unit coupled to the armature circuit to establish a corresponding feedback signal for all modes of motor operation proportional to the armature current voltage drop of the motor armature and a voltage signal proportional to the armature voltage, a second summating means connected to said first summating means and to said second feedback means to provide a summated control signal proportional to the algebraic sum of said signal and including the difference of said armature voltage and said armature current voltage drop added to said error signal to establish continuous tracking of the counterelectromotive voltage of such armature, gated means connected in said armature circuit and having an alternating current input and a periodic output, and means connecting the gated means to said second summating means and having an alternating current reference voltage signal and gating said gating means to conduct in accordance with the control signal intercept with said voltage signal to control the motor for all modes of motor operation.

Claim 21

In a motor control circuit for a motor having an armature connected in an armature circuit to an alternating current supply, command means to establish a command voltage signal proportional to a desirEd motor operation, first voltage feedback means to establish a feedback signal proportional to the armature voltage, first summating means connected to said command means and to said feedback means to provide an error voltage signal, second feedback means having a first current sensing unit coupled to the armature circuit to establish a corresponding feedback signal for all modes of motor operation proportional to the armature current voltage drop of the motor armature and a voltage signal proportional to the armature voltage, a second summating means connected to said first summating means and to said second feedback means to provide a summated control signal proportional to the algebraic sum of said signal and including the difference of said armature voltage and said armature current voltage drop added to said error signal to establish continuous tracking of the counterelectromotive voltage of such armature, gated means connected in said armature circuit and having an alternating current input and a periodic output, and means connecting the gated means to said second summating means and having an alternating current reference voltage signal and gating said gating means to conduct in accordance with the control signal intercept with said voltage signal to control the motor for all modes of motor operation.