Power amplifier having source of different power capabilities for energizing a servo motor

Claim 2

A control system for a motor drive wherein the motor drives a load to a desired state under the control of an error signal having a magnitude which is a function of the difference between the desired state of the load and the present state of the load, comprising electrical drive means for driving said motor, said electrical drive means comprising means for providing a maximum power in response to an error signal and dissipating power to provide less than the maximum power to the load in response to said error signal, the maximum power which said drive means is capable of supplying to said load in response to an error signal being determined by the magnitude of the supply voltage for said drive means, and means for changing the magnitude of the supply voltage of said drive means as a direct function of the magnitude of the error signal so that said maximum power tracks said error signal, and increases when said error signal increases and decreases when said error signal decreases.

Claim 3

A control system as defined in claim 1 wherein the span of magnitudes of said error signal comprises a plurality of ranges of magnitudes, and said means for changing the magnitude of the supply voltage comprises a plurality of voltage supplies, and a plurality of energizable switching means each for closing a circuit path from a voltage supply of the plurality of voltage supplies to said drive means in order to couple a predetermined supply voltage to said drive means, each of said switching means being energized in accordance with a predetermined one of said ranges of said error signal.

Claim 4

A control system for a motor drive wherein the motor drives a load to a desired state under the control of an error signal having a magnitude which is a function of the difference between the desired state of thE load and the present state of the load, comprising electrical drive means for driving said motor, the maximum power which said drive means is capable of supplying to said load in response to an error signal being limited by the magnitude of the supply voltage for said drive means, and means for changing the magnitude of the supply voltage of said drive means as a direct function of the magnitude of the error signal, wherein the control system further comprises a plurality of voltage supplies, a plurality of energizable switching means each for closing a circuit path from a voltage supply of the plurality of voltage supplies to said drive means in order to couple a predetermined supply voltage to said drive means, each of said switching means being energized in accordance with a predetermined magnitude level of said error signal, wherein the error signal is an analog error signal and an analog-to-digital converter produces a plurality of digital control signals each of which is representative of a predetermined range of magnitudes of the analog error signal for controlling said means for changing the supply voltage to said drive means.

Claim 5

A control system for a motor drive wherein the motor drives a load to a desired state under the control of an error signal having a magnitude which is a function of the difference between the desired state of thE load and the present state of the load, comprising electrical drive means for driving said motor, the maximum power which said drive means is capable of supplying to said load in response to an error signal being limited by the magnitude of the supply voltage for said drive means, and means for changing the magnitude of the supply voltage of said drive means as a direct function of the magnitude of the error signal, wherein the control system further comprises a plurality of voltage supplies, a plurality of energizable switching means each for closing a circuit path from a voltage supply of the plurality of voltage supplies to said drive means in order to couple a predetermined supply voltage to said drive means, each of said switching means being energized in accordance with a predetermined magnitude level of said error signal, wherein the error signal is an analog error signal and an analog-to-digital converter produces a plurality of digital control signals each of which is representative of a predetermined range of magnitudes of the analog error signal for controlling said means for changing the supply voltage to said drive means.

Claim 6

A control system as defined in claim 3 wherein said means for changing the supply voltage to said drive means comprises a plurality of diodes and a plurality of transistors, each transistor having its collector-emitter path coupled in series with a diode between one terminal of an associated voltage supply and a supply terminal of said drive means, and each diode is reverse biased when a transistor associated with a higher magnitude supply voltage is energized.

Claim 7

A control system as defined in claim 3 wherein said means for changing the supply voltage to said drive means comprises a plurality of controlled-rectifiers each of which has its anode-cathode path coupled between one terminal of an associated voltage supply and a supply terminal of said drive means particular controlled rectifiers of the plurality of controlled rectifiers being reverse biased when any controlled-rectifier associated with a higher magnitude supply voltage is energized.

Claim 8

A control system as defined in claim 5 further comprising means constructed to produce an output signal when the difference between a signal representing the voltage which is being supplied to said drive means and a signal representing the error signal exceeds a predetermined magnitude and means responsive to the output signal for interrupting the anode-cathode current path of conducting controlled-rectifiers.

Claim 9

A control system for a motor drive wherein the motor drives a load to a desired state under the control of an error signal indicating a difference between the desired state and the present state of the load comprising electrical drive means for driving said motor, said electrical drive means comprising power supply means and error signal responsive means energized by said power supply means for supplying power in dependency on said error signal and limited by the voltage of said power supply means, and means for changing the magnitude of the supply voltage of said drive means as a function of the magnitude of the error signal, said error signal being an analog error signal, and an analog to digital converter for providing a plurality of digital control signals each of which is representative of a predetermined range of magnitudes of the analog error signal for controlling said means for changing the supply voltage to said drive means.

Claim 10

A control system for a motor drive wherein the motor drives a load to a desired state under the control of an error signal indicating a difference between the desired state and the present state of the load comprising electrical drive means for driving said motor, said electrical drive means comprising power supply means and error signal responsive means energized by said power supply means for supplying power in dependency on said error signal and limited by the voltage of said power supply means, and means for changing the magnitude of the supply voltage of said drive means as a function of the magnitude of the error signal, said error signal being an analog error signal, and an analog to digital converter for providing a plurality of digital control signals each of which is representative of a predetermined range of magnitudes of the analog error signal for controlling said means for changing the supply voltage to said drive means.

Claim 11

A control system for a load supply in which current is supplied to the load in response to the input signal comprising a voltage supply, electrical supply means energized by said voltage supply for supplying said current to said load which is limited by the magnitude of the supply voltage of said electrical supply means, means for changing the magnitude of the supply voltage of said supply means as a function of the magnitude of the input signal, said input signal being an analog driving signal, and an analog to digital converter providing a pluRality of digital control signals, each of which is representative of a predetermined range of the magnitudes of the analog driving signal for controlling said means for changing the supply voltage to said electrical supply means.

Claim 12

A control system for a load supply in which current is supplied to the load in response to the input signal comprising a voltage supply, electrical supply means energized by said voltage supply for supplying said current to said load which is limited by the magnitude of the supply voltage of said electrical supply means, means for changing the magnitude of the supply voltage of said supply means as a function of the magnitude of the input signal, said input signal being an analog driving signal, and an analog to digital converter providing a pluRality of digital control signals, each of which is representative of a predetermined range of the magnitudes of the analog driving signal for controlling said means for changing the supply voltage to said electrical supply means.

Claim 13

A control system as defined in claim 8 wherein said means for changing the supply voltage to said supply means comprises a plurality of diodes, and a plurality of transistors each transistor having its collector-emitter path coupled in series with a diode between one terminal of an associated voltage supply and a supply terminal of said supply means, and each diode is reverse biased when a transistor associated with a higher magnitude supply voltage is energized.

Claim 14

A control system as defined in claim 8 wherein said means for changing the supply voltage to said supply means comprises a plurality of controlled-rectifiers, each of which has its anode-cathode path coupled between one terminal of an associated voltage supply and a supply terminal of said supply means, particular controlled-rectifiers of the plurality of controlled rectifiers being reverse biased when any controlled-rectifier associated with a higher magnitude supply voltage is energized.

Claim 15

A control system as defined in claim 10 further comprising means constructed to produce an output signal when the difference between a signal representing the voltage which is being supplied to said supply means and a signal representing the input signal exceeds a predetermined magnitude and means responsive to the output signal for interrupting the anode-cathode current path of conducting controlled-rectifiers.

Claim 16

A control system for a load supply in which current is supplied to the load in response to the input signal comprising a voltage supply, electrical supply means energized by said voltage supply for supplying said current to said load which is limited by the magnitude of the supply voltage of said electrical supply means, means for changing the magnitude of the supply voltage of said supply means as a function of the magnitude of the input signal, a plurality of voltage supplies, a plurality of energizable switching means each for closing a circuit path from a voltage supply of the plurality of voltage supplies to the electrical supply means in order to couple a predetermined supply voltage to said supply means, each of said switching means being energized in accordance with a predetermined magnitude level of said input signal, said input signal being an analog signal and an analog-to-digital converter produces a plurality of digital control signals each of which is representative of a predetermined range of magnitudes of the analog input signal for controlling said means for changing the supply voltage to said supply means.

Claim 17

A control system for a load supply in which current is supplied to the load in response to the input signal comprising a voltage supply, electrical supply means energized by said voltage supply for supplying said current to said load which is limited by the magnitude of the supply voltage of said electrical supply means, means for changing the magnitude of the supply voltage of said supply means as a function of the magnitude of the input signal, a plurality of voltage supplies, a plurality of energizable switching means each for closing a circuit path from a voltage supply of the plurality of voltage supplies to the electrical supply means in order to couple a predetermined supply voltage to said supply means, each of said switching means being energized in accordance with a predetermined magnitude level of said input signal, said input signal being an analog signal and an analog-to-digital converter produces a plurality of digital control signals each of which is representative of a predetermined range of magnitudes of the analog input signal for controlling said means for changing the supply voltage to said supply means.

Claim 18

In a servo motor system, a motor to be energized in accordance with the magnitude of an error signal including electrical circuit means for energizing said motor in response to said error signal to vary the speed thereof in accordance with the magnitude of said signal, said electrical circuit means including power control means for determining the maximum power which said electrical circuit means is capable of delivering and dissipating power to provide less than the maximum power to the load in response to an error signal, and means for actuating said power control means in response to the magnitude of said error signal to change the maximum power capability of said electrical circuit means as a direct function of said error signal.

Claim 19

In a servo motor system, a motor to be energized in accordance with the magnitude of an error signal including electrical circuit means for energizing said motor in response to said error signal to vary the speed thereof in accordance with the magnitude of said signal, said electrical circuit means including power control means for determining the maximum power which said electrical circuit means is capable of delivering and dissipating power to provide less than the maximum power to the load in response to an error signal, and means for actuating said power control means in response to the magnitude of said error signal to change the maximum power capability of said electrical circuit means as a direct function of said error signal.

Claim 20

A servo system as defined in claim 13 wherein said electrical circuit means is a power amplifier and said power control means comprises a power supply for said amplifier and means for changing the magnitude of the power supply for said amplifier.

Claim 21

A servo system as defined in claim 14 wherein said motor is a direct current motor and said direct current amplifier supplies armature current to said motor.

Claim 22

A control system for a load in which electrical power is to be supplied to the load in accordAnce with the magnitude of a variable input signal comprising a direct current power amplifier for supplying current to said load in response to an error signal and limited by the magnitude of the power capability of said amplifier and dissipating power to provide less than the maximum power to the load in response to said error signal, and means for switching the magnitude of the power capability of said amplifier as a direct function of the magnitude of the input signal.

Claim 23

A control system for a load in which electrical power is to be supplied to the load in accordAnce with the magnitude of a variable input signal comprising a direct current power amplifier for supplying current to said load in response to an error signal and limited by the magnitude of the power capability of said amplifier and dissipating power to provide less than the maximum power to the load in response to said error signal, and means for switching the magnitude of the power capability of said amplifier as a direct function of the magnitude of the input signal.

Claim 24

In a control system, a power supply having output terminals, and comprising power control means actuatable to different states to control the power available at said output terminals, a load, dissipative circuit means of variable conductivity, means connecting said load and circuit means in series across said terminals to energize said load in dependency on the conductivity of said circuit means, said circuit means comprising means responsive to a control signal for varying the conductivity of said circuit means for controlling the energization of the load, and additional means responsive to said control signal to actuate said power control means to change the power available at said terminals in direct dependence on the magnitude of said control signal.

Claim 25

In a control system, a power supply having output terminals, and comprising power control means actuatable to different states to control the power available at said output terminals, a load, dissipative circuit means of variable conductivity, means connecting said load and circuit means in series across said terminals to energize said load in dependency on the conductivity of said circuit means, said circuit means comprising means responsive to a control signal for varying the conductivity of said circuit means for controlling the energization of the load, and additional means responsive to said control signal to actuate said power control means to change the power available at said terminals in direct dependence on the magnitude of said control signal.

Claim 26

A control system as defined in claim 17 wherein said power supply comprises a plurality of voltage supplies for supplying different voltages, and said power control means comprises switching means for connecting said voltage supplies to selectively provide different voltages at said output terminals.

Claim 27

In a control system, a power supply having output terminals, and comprising power control means actuatable to different states to control the power available at said output terminals, a load, circuit means of variable conductivity, means connecting said load and circuit means in series across said terminals to energize said load in dependency on the conductivity of said circuit means, said circuit means comprising means responsive to a control signal for varying the conductivity of said circuit means for controlling the energization of the load, and additional means responsive to said control signal to actuate said power control means to change the power available at said terminals in direct dependence on the magnitude of said control signal, said power supply comprising a plurality of voltage supplies for supplying different voltages, and said power control means comprising switching means for connecting said voltage supplies to selectively provide different voltages at said output terminals, said additional means comprising an analog-to-digital converter for providing digital signals representing ranges of magnitude of said input signal for actuating said switching means.

Claim 28

In a control system, a power supply having output terminals, and comprising power control means actuatable to different states to control the power available at said output terminals, a load, circuit means of variable conductivity, means connecting said load and circuit means in series across said terminals to energize said load in dependency on the conductivity of said circuit means, said circuit means comprising means responsive to a control signal for varying the conductivity of said circuit means for controlling the energization of the load, and additional means responsive to said control signal to actuate said power control means to change the power available at said terminals in direct dependence on the magnitude of said control signal, said power supply comprising a plurality of voltage supplies for supplying different voltages, and said power control means comprising switching means for connecting said voltage supplies to selectively provide different voltages at said output terminals, said additional means comprising an analog-to-digital converter for providing digital signals representing ranges of magnitude of said input signal for actuating said switching means.

Claim 29

A control system for a motor drive wherein the motor drives a load to a desired condition under the control of an error signal having a magnitude which is a function of the difference between the desired condition of the load and the present condition of the load, comprising electrical drive means for driving said motor, said electrical drive means having a plurality of states and a maximum available power in each state with said maximum available power being different for different states, said electrical drive means including means responsive to said error signal for delivering a portion of said maximum available power in a given state to said load as a function of the magnitude of said error signal, state-switching means for switching said drive means between said states, and switch control means responsive to the range of magnitude of said error signal to switch said drive means between said states to increase maximum power available to said load as said error signal changes ranges by reaching predetermined magnitudes.

Claim 30

A control system for a motor drive wherein the motor drives a load to a desired condition under the control of an error signal having a magnitude which is a function of the difference between the desired condition of the load and the present condition of the load, comprising electrical drive means for driving said motor, said electrical drive means having a plurality of states and a maximum available power in each state with said maximum available power being different for different states, said electrical drive means including means responsive to said error signal for delivering a portion of said maximum available power in a given state to said load as a function of the magnitude of said error signal, state-switching means for switching said drive means between said states, and switch control means responsive to the range of magnitude of said error signal to switch said drive means between said states to increase maximum power available to said load as said error signal changes ranges by reaching predetermined magnitudes.