Analog input output linearization control

• US 9,369,041 B2
• Filed: 08/21/2014
• Issued: 06/14/2016
• Est. Priority Date: 06/18/2009
• Status: Active Grant

• Current Assignee: Cirasys, Inc., Board of Regents of the University of Texas System (University of Texas System)
• Original Assignee: Cirasys, Inc., Board of Regents of the University of Texas System (University of Texas System)
• Inventors: Paduvalli, Vikas V., Hunt, Louis R., Balsara, Poras T., Taylor, Robert J.
• Primary Examiner(s): Berhane, Adolf
• Assistant Examiner(s): LEE III, HENRY E
• Application Number:
  US14/465,260
• Publication Number:
  US 20140361754A1
• Time in Patent Office: 663 Days
• US Class Current: 1/1
• CPC Class Codes: H02M 3/156 with automatic control of output voltage or current, e.g. switching regulators
• CPC Class Codes: H02M 3/158 including plural semiconductor devices as final control devices for a single load
• CPC Class Codes: H03K 7/08 Duration or width modulation ; Duty cycle modulation

Abstract

A voltage converter for converting an input voltage to an output voltage is disclosed. The voltage converter includes a voltage converter circuit having a set of switches, a switch driver connected to the voltage converter circuit, a controller connected to the switch driver and the output voltage, a target output voltage connected to the controller, a control signal generated by the controller for the switch driver that includes a duty ratio based on the target output voltage and the output voltage. The switch driver is configured to apply the control signal to the set of switches and the voltage converter circuit generates the output voltage based on the duty ratio to match the target output voltage.

Claims

1. A voltage converter for converting an input voltage to an output voltage comprising:

a voltage converter circuit comprising a set of switches;

a switch driver connected to the voltage converter circuit;

a controller connected to the switch driver and the output voltage;

a target output voltage connected to the controller;

a control signal generated by the controller for the switch driver, comprising a duty ratio based on the target output voltage and the output voltage;

the switch driver configured to apply the control signal to the set of switches;

whereby the voltage converter circuit generates the output voltage based on the duty ratio to match the target output voltage;

the duty ratio given by;

2. The voltage converter of claim 1, wherein the controller is configured to generate the control signal based on input-output feedback linearization of a set of state variables with stable zero dynamics.

3. The voltage converter of claim 2, wherein the voltage converter circuit comprises a buck converter circuit.

4. The voltage converter of claim 2, wherein the voltage converter circuit comprises a boost converter circuit.

5. The voltage converter of claim 2, wherein the voltage converter circuit comprises a buck-boost converter circuit.

6. The voltage converter of claim 2, wherein the controller further comprises:

a summing block connected to the target output voltage and the output voltage;

a difference between the output voltage and the target output voltage, generated by the summing block;

a proportional gain block connected to the summing block, configured to produce a voltage signal from the difference;

an input impedance connected to the proportional gain block;

an operational amplifier connected to the input impedance;

a feedback impedance connected in parallel with the operational amplifier;

an inverting block connected to the operational amplifier;

a differentiator connected to the operational amplifier and the output voltage, configured to generate a differentiated output voltage from the output voltage;

the duty ratio formed by the inverting block.

7. The voltage converter of claim 2, wherein the input voltage is a fixed input voltage.

8. The voltage converter of claim 2, wherein the input voltage is a time-varying input voltage.

9. The voltage converter of claim 2, wherein the target output voltage is a fixed target output voltage and wherein the output voltage is a fixed target output voltage.

10. The voltage converter of claim 2, wherein the target output voltage is a time-varying target output voltage and wherein the output voltage is a time-varying output voltage.

11. A voltage converter for converting an input voltage to an output voltage comprising:

a voltage converter circuit comprising a set of switches;

a switch driver connected to the voltage converter circuit;

a controller connected to the switch driver and the output voltage;

a target output voltage connected to the controller;

a control signal generated by the controller for the switch driver, comprising a duty ratio based on the target output voltage and the output voltage;

the switch driver configured to apply the control signal to the set of switches;

whereby the voltage converter circuit generates the output voltage based on the duty ratio to match the target output voltage;

the duty ratio given by;

12. The voltage converter of claim 11, wherein the controller further comprises:

a summing block connected to the target output voltage and the output voltage;

a difference between the output voltage and the target output voltage, generated by the summing block;

a proportional gain block connected to the summing block, configured to produce a voltage signal from the difference;

an input impedance connected to the proportional gain block;

an operational amplifier connected to the input impedance;

a feedback capacitance connected in parallel with the operational amplifier to form an integrator;

an inverting block connected to the operational amplifier;

a differentiator connected to the operational amplifier and the output voltage, configured to generate a differentiated output voltage from the output voltage;

the duty ratio formed by the inverting block.

13. A voltage converter for converting an input voltage to an output voltage comprising:

a voltage converter circuit comprising a set of switches;

a switch driver connected to the voltage converter circuit;

a controller connected to the switch driver and the output voltage;

a target output voltage connected to the controller;

a control signal generated by the controller for the switch driver, comprising a duty ratio based on the target output voltage and the output voltage;

the switch driver configured to apply the control signal to the set of switches;

whereby the voltage converter circuit generates the output voltage based on the duty ratio to match the target output voltage;

wherein the target output voltage is a time-varying target output voltage and wherein the output voltage is a time-varying output voltage;

wherein the duty ratio is a time-varying control signal given by;

14. The voltage converter of claim 13, wherein the controller further comprises:

a first summing block connected to the time-varying target output voltage and the time-varying output voltage;

a difference between the time-varying output voltage and the time-varying target output voltage, generated by the first summing block;

a proportional gain block connected to the first summing block;

an intermediate voltage produced by the proportional gain block from the difference and a proportional gain;

a second summing block connected to the proportional gain block;

a time derivative input voltage connected to the second summing block;

a voltage signal produced by the second summing block from the intermediate voltage and the time derivative input voltage;

an input impedance connected to the second summing block;

an operational amplifier connected to the input impedance;

a feedback impedance connected in parallel with the operational amplifier;

an inverting block connected to the operational amplifier;

a differentiator connected to the operational amplifier and the time-varying output voltage, configured to generate a differentiated time-varying output voltage from the time-varying output voltage;

wherein the duty ratio is a time-varying control signal formed by the inverting block.

15. The voltage converter of claim 14, wherein the time-varying target output voltage is a known function of time.

16. The voltage converter of claim 14, wherein the differentiator is a second differentiator and the controller further comprises:

a first differentiator connected to the time-varying target output voltage and the second summing block;

the time derivative input voltage generated by the first differentiator.

17. The voltage converter of claim 16, wherein the time-varying input voltage is an arbitrary voltage input.

18. In a voltage converter comprising a voltage converter circuit comprising a set of switches, a switch driver connected to the voltage converter circuit, and a controller connected to the switch driver, a method for converting an input voltage to an output voltage comprising the steps of:

receiving a target output voltage;

receiving the input voltage;

generating a feedback output voltage;

sensing the feedback output voltage;

generating a control signal from the target output voltage and the feedback output voltage;

changing a set of switch states of the set of switches based on the control signal;

applying the set of switch states to the set of switches to generate the output voltage;

wherein the step of generating a control signal further comprises the step of calculating a duty ratio;

wherein the step of calculating a duty ratio further comprises the steps of;

implementing input-output linearization;

sampling a set of feedback output voltages;

calculating a time interval between each of the set of feedback output voltages; and

,

adjusting the duty ratio with an integrator delay and the time interval.

19. The method of claim 18, further comprising the steps of:

setting an initial gain for the controller;

setting a gain and a capacitance for the controller; and

,

determining an input impedance and a feedback impedance for the controller.

20. The method of claim 18, wherein the target output voltage is a time-varying target output voltage and the feedback output voltage is a time-varying feedback output voltage, and wherein the step of generating a control signal further comprises the steps of:

differentiating the time-varying target output voltage to create a differentiated time-varying target output voltage; and

,

calculating the duty ratio from the differentiated time-varying target output voltage and the time-varying feedback output voltage.

21. The method of claim 18, wherein the time-varying target output voltage is a known function of time, and wherein the step of calculating further comprises the step of calculating a time-varying duty ratio from the known function of time and the time-varying feedback output voltage.

22. The method of claim 18, wherein the time-varying target output voltage is an arbitrary voltage, and wherein the step of calculating further comprises the step of calculating a time-varying duty ratio from the arbitrary voltage and the time-varying feedback output voltage.