Hysteresis compensator for control systems

Claim 2

In a control in which a control signal for a controlled device is produced in response to changes in an input signal, a time lag occurring in the response of said controlled device to changes in said input signal due to hysteresis in said control system, the improvement comprising: an integrator, said input signal being connected to the input of said integrator, the output of said integrator changing in a direction determined by the polarity of said input signal; a first source of a fixed bias signal having a first polarity and a second source of a fixed bias signal having a polarity opposite to said first polarity; summing means having a pair of inputs and providing an output signal as a function of the summation of signals applied to its inputs, one of said inputs being connected to the output of said integrator; and selector means connected to said input signal and responsive to the polarity thereof for connecting a corresponding one of said bias signal sources to the other input of said summing means, whereby the output of said summing means will be increased in value over the output of said integrator by the magnitude of said bias signals in response to a positive input signal and the output of said summing means will be decreased below the value of the output of said integrator by the magnitude of said bias signals in response to a negative input signal.

Claim 3

In a control in which a control signal for a controlled device is produced in response to changes in an input signal, a time lag occurring in the response of said controlled device to changes in said input signal due to hysteresis in said control system, the improvement comprising: a delay unit connected to said input signal and providing an output signal delayed therefrom; a first summing means having a positive input thereto connected to said input signal and having a negative input thereto connected to the delayed output signal of said delay unit, the output of said first summing means providing a signal the polarity of which is a function of the direction of change of said input signal; and a first source of a fixed bias signal having a first polarity and a second source of a fixed bias signal having a polarity opposite to said first polarity; second summing means having a pair of inputs and providing an output signal as a function of the summation of signals applied to its inputs, one of said inputs being connected to said input signal; and selector means connected to the output of said first summing means and responsive to the polarity thereof for connecting a corresponding one of said bias signal sources to the other input of said second summing means, whereby the output of said second summing means will be increased in value over said input signal by the magnitude of said bias signals in response to a positive input signal and the output of said second summing means will be decreased from the value of said input signal by the magnitude of said bias signals in response to a negative input signal.

Claim 4

In a control in which a control signal for a controlled device is produced in response to changes in an input signal, a time lag occurring in the response of said controlled device to changes in said input signal due to hysteresis in said control system, the improvement comprising: a delay unit connected to said input signal and providing an output signal delayed therefrom; a first summing means having a positive input thereto connected to said input signal and having a negative input thereto connected to the delayed output signal of said delay unit, the output of said first summing means providing a signal the polarity of which is a function of the direction of change of said input signal; and a first source of a fixed bias signal having a first polarity and a second source of a fixed bias signal having a polarity opposite to said first polarity; second summing means having a pair of inputs and providing an output signal as a function of the summation of signals applied to its inputs, one of said inputs being connected to said input signal; and selector means connected to the output of said first summing means and responsive to the polarity thereof for connecting a corresponding one of said bias signal sources to the other input of said second summing means, whereby the output of said second summing means will be increased in value over said input signal by the magnitude of said bias signals in response to a positive input signal and the output of said second summing means will be decreased from the value of said input signal by the magnitude of said bias signals in response to a negative input signal.

Claim 5

In a control in which a control signal for a controlled device is produced in an integrator in response to changes in an input signal, a time lag occurring in the response of said controlled device to changes in the integral of said input signal due to hysteresis in said control system, the method comprising: providing a first fixed bias signal having a first polarity and a second fixed bias signal having a polarity opposite to said first polarity; selecting one of said bias signals in response to the polarity of said input signal; and summing the output of said integrator with the selected bias signal to provide said control signal, whereby said control signal will be increased in value over the output of said integrator by the magnitude of said bias signals in response to a positive input signal and said control signal will be decreased from the value of the output of said integrator by the value of said bias signals in response to a negative input signal.

Claim 6

In a control in which a control signal for a controlled device is produced in an integrator in response to changes in an input signal, a time lag occurring in the response of said controlled device to changes in the integral of said input signal due to hysteresis in said control system, the method comprising: providing a first fixed bias signal having a first polarity and a second fixed bias signal having a polarity opposite to said first polarity; selecting one of said bias signals in response to the polarity of said input signal; and summing the output of said integrator with the selected bias signal to provide said control signal, whereby said control signal will be increased in value over the output of said integrator by the magnitude of said bias signals in response to a positive input signal and said control signal will be decreased from the value of the output of said integrator by the value of said bias signals in response to a negative input signal.

Claim 7

In a control in which a control signal for a controlled device is produced in response to changes in an input signal, a time lag occurring in the response of said controlled device to changes in said input signal due to hysteresis in said control system, the method comprising: delaying said input signal and providing an output signal delayed therefrom; combining said input signal and said delayed signal in a summing means to provide a signal the polarity of which is indicative of the direction of change of said input signal; providing a first fixed bias signal having a first polarity and a second fixed bias signal having a polarity opposite to said first polarity; and summing said input signal with one of said bias signals in dependence on the polarity of the signal output of said summing means to provide said control signal, whereby said control signal will be increased in value over the output of said integrator by the magnitude of said bias signals in response to a positive input signal and said control signal will be decreased from the value of the output of said integrator by the value of said bias signals in response to a negative input signal.

Claim 8

In a control in which a control signal for a controlled device is produced in response to changes in an input signal, a time lag occurring in the response of said controlled device to changes in said input signal due to hysteresis in said control system, the method comprising: delaying said input signal and providing an output signal delayed therefrom; combining said input signal and said delayed signal in a summing means to provide a signal the polarity of which is indicative of the direction of change of said input signal; providing a first fixed bias signal having a first polarity and a second fixed bias signal having a polarity opposite to said first polarity; and summing said input signal with one of said bias signals in dependence on the polarity of the signal output of said summing means to provide said control signal, whereby said control signal will be increased in value over the output of said integrator by the magnitude of said bias signals in response to a positive input signal and said control signal will be decreased from the value of the output of said integrator by the value of said bias signals in response to a negative input signal.