Efficient Battery Tester

• US 20190250217A1
• Filed: 04/23/2019
• Published: 08/15/2019
• Est. Priority Date: 06/09/2015
• Status: Active Grant

• Current Assignee: Premier Technologies Pty. Ltd.
• Original Assignee: Premier Technologies Pty. Ltd.
• Inventors: Cheng, Chun Sing, Lau, Wing Hong, Chung, Shu Hung Henry
• Granted Patent: US 10,866,285 B2
• Time in Patent Office: Days
• CPC Class Codes: G01R 31/3647 for determining the ability of a battery to perform a critical function, e.g. cranking
• CPC Class Codes: G01R 31/3648 comprising digital calculation means, e.g. for performing an algorithm
• CPC Class Codes: G01R 31/385 Arrangements for measuring battery or accumulator variables for monitoring G01R31/382
• CPC Class Codes: G01R 31/389 Measuring internal impedance, internal conductance or related variables
• CPC Class Codes: G01R 31/392 Determining battery ageing or deterioration, e.g. state of health

Abstract

A battery tester for efficiently extracting intrinsic characteristics of a battery. The battery tester comprises a sensing unit, a controller, a bi-directional power converter, and an energy storage unit so that energy discharged from a battery during testing is stored in the energy storage unit and recycled back to the battery. The battery tester uses a high current pulse test and a switching excitation test with a modified particle swarm optimization algorithm to analyze precise model parameters that can be used to describe the health conditions of a battery.

Claims

1. An object tester for evaluating intrinsic characteristics of an object that is configured to accept bi-directional power flow, comprising:

a. at least one sensor for sensing voltage and current;

b. an energy storage unit for temporarily storing power from the object;

c. a bi-directional power converter for facilitating energy transfer between the object and the energy storage unit;

d. a controller for controlling the bi-directional power converter, the controller comprising a processor, a non-transitory computer readable storage medium, and instructions stored in the non-transitory computer readable storage medium, which when executed by the processor cause the processor to perform an object test method, wherein the object test method comprises transferring energy from the object to the energy storage unit and transferring energy from the energy storage unit to the object using the bi-directional power converter; and

e. a display, wherein a user interface on the display provides controls operable for selecting the object test method;

f. a power supply, whereby the power supply supplies energy to the object tester in order to test a deeply discharged object.

g. wherein the object test method is selected from a first test mode for quick evaluation of the object or a second test mode for precise evaluation of the object, wherein the first test mode comprises a high current pulse test and the second test mode comprises the high current pulse test and a switching excitation test;

h. wherein the high current pulse test comprises drawing a high current from the object to the energy storage unit over a short period of time, returning energy from the energy storage unit to the object, and measuring voltage and current changes using the at least one sensor;

i. wherein the switching excitation test comprises transferring energy from the object to the energy storage unit and transferring energy from the energy storage unit to the object at a fixed frequency, and measuring voltage and current using the at least one sensor;

j. wherein the first test mode determines object internal resistance, cold cranking ampere (“

CCA”

), and state of charge (“

SOC”

), wherein object internal resistance is determined by evaluating

2. The object tester of claim 1, wherein the recursive algorithm comprises:

a. initializing a set of particles representative of voltage and current of the object, wherein each particle has a velocity and a position;

b. updating the set of particles for a number of iterations, wherein updating the set of particles comprises;

i. determining an inaccuracy value of each particle using an inaccuracy function, wherein the inaccuracy function measures a difference between actual object voltage-current characteristics and an electrical model with estimated intrinsic parameters for a period of time, wherein a particle with a lowest inaccuracy value is considered a best particle of the set of particles, and wherein a particle with a highest inaccuracy value is considered a worst particle of the set of particles, wherein an inaccuracy value of each particle is determined by evaluating function

3. The object tester of claim 1, wherein the object tester is installed in an automobile to perform an analysis of an automobile object.

4. The object tester of claim 1, wherein the object tester is a standalone device operable to connect with a standalone object and display test results of the standalone object.

5. An object tester for evaluating intrinsic characteristics of an object that is configured to accept bi-directional power flow, comprising:

a. at least one sensor for sensing voltage and current;

b. an energy storage unit for temporarily storing power from the object, wherein the energy storage unit comprises a supercapacitor;

c. a bi-directional power converter for facilitating energy transfer between the object and the energy storage unit;

d. a controller for controlling the bi-directional power converter, the controller comprising;

i. a processor, a non-transitory computer readable storage medium, and instructions stored in the non-transitory computer readable storage medium, which when executed by the processor cause the processor to perform at least one object test method, wherein the at least one object test method comprises transferring energy from the object to the energy storage unit and transferring energy from the energy storage unit to the object using the bi-directional power converter.

ii. wherein the at least one object test method further comprises conducting a switching excitation test, wherein the switching excitation test comprises transferring energy from the object to the energy storage unit and transferring energy from the energy storage unit to the object at a fixed frequency, and measuring voltage and current using the at least one sensor.

6. The object tester of claim 5 further comprising a user interface on a display, wherein the user interface comprises controls for selecting the at least one object test method.

7. The object tester of claim 5, wherein the at least one object test method comprises conducting a high current pulse test, wherein the high current pulse test comprises drawing a high current from the object to the energy storage unit over a short period of time, returning energy from the energy storage unit to the object, and measuring voltage and current changes using the at least one sensor.

8. The object tester of claim 5, further comprising determining the intrinsic characteristics of the object by using a recursive algorithm to increase accuracy of an electrical model of the object, wherein the recursive algorithm comprises:

a. initializing a set of particles representative of voltage and current of the object, wherein each particle has a velocity and a position;

b. updating the set of particles for a number of iterations, wherein updating the set of particles comprises;

i. determining an inaccuracy value of each particle using an inaccuracy function, wherein the inaccuracy function measures a difference between actual object voltage-current characteristics and an electrical model with estimated intrinsic parameters for a period of time, wherein a particle with a lowest inaccuracy value is considered a best particle of the set of particles, and wherein a particle with a highest inaccuracy value is considered a worst particle of the set of particles;

ii. generating a replacement particle by generating and injecting a perturbation into the best particle;

iii. evaluating an inaccuracy value of the replacement particle using the inaccuracy function;

iv. if the replacement particle has a lower inaccuracy value than the best particle, replacing the best particle with the replacement particle in the set of particles, or else replacing the worst particle with the replacement particle in the set of particles; and

v. updating the velocity and position of each particle in the set of particles; and

c. determining state of charge, cold cranking ampere, and internal resistance of the electrical model of the object based on the set of particles.

9. The object tester of claim 5, wherein determining an inaccuracy value of each particle is determined by evaluating function

10. The object tester of claim 5, wherein state of charge (“

SOC”

) at time t is determined by evaluating

11. An object tester for evaluating intrinsic characteristics of an object that is configured to accept bi-directional power flow, comprising:

a. at least one sensor for sensing voltage and current;

b. an energy storage unit for temporarily storing power from the object, wherein the energy storage unit comprises a supercapacitor;

c. a bi-directional power converter for facilitating energy transfer between the object and the energy storage unit;

d. a controller for controlling the bi-directional power converter, the controller comprising;

i. a processor, a non-transitory computer readable storage medium, and instructions stored in the non-transitory computer readable storage medium, which when executed by the processor cause the processor to perform at least one object test method, wherein the at least one object test method comprises transferring energy from the object to the energy storage unit and transferring energy from the energy storage unit to the object using the bi-directional power converter;

e. wherein the object characteristics determined are object internal resistance, cold cranking ampere (“

CCA”

), and state of charge (“

SOC”

), wherein object internal resistance is determined by evaluating

12. A method of testing objects for intrinsic characteristics, the method comprising:

at a circuit having a controller, a bi-directional power converter, an energy storage unit, and at least one sensor, wherein the energy storage unit comprises a supercapacitor;

a. performing an object test method, wherein the object test method comprises;

i. recording a voltage and current of an object;

ii. directing the controller to transfer energy from the object to the energy storage unit using the bi-directional power converter;

iii. directing the controller to transfer energy from the energy storage unit to the object using the bi-directional power converter; and

iv. measuring voltage and current of the circuit using the at least one sensor; and

b. determining intrinsic characteristics of the object based on measured voltage and current of the circuit.

13. The method for testing objects of claim 12, further comprising providing a user interface on a display, wherein the user interface provides a selection of object test methods to perform on the object.

14. The method for testing objects of claim 13, wherein the selection of object test methods comprises a first object test method to simulate a high current pulse, wherein the step of directing the controller to transfer energy from the object to the energy storage unit using the bi-directional power converter is conducted over a short period of time.

15. The method for testing objects of claim 12, wherein the intrinsic characteristics comprise object internal resistance, cold cranking ampere (“

CCA”

), and state of charge (“

SOC”

), wherein object internal resistance is determined by evaluating

16. The method for testing objects of claim 13, wherein the selection of object test methods comprises a second object test method to simulate switching excitation, wherein the steps of directing the controller to transfer energy from the object to the energy storage unit and from the energy storage unit to the object are performed at a fixed frequency.

17. The method for testing objects of claim 12, wherein determining intrinsic characteristics of the object comprises using a recursive algorithm to increase accuracy of an electrical model of the object, wherein the recursive algorithm comprises:

a. initializing a set of particles representative of voltage and current of the object, wherein each particle has a velocity and a position;

b. updating the set of particles for a number of iterations, wherein updating the set of particles comprises;

i. determining an inaccuracy value of each particle using an inaccuracy function, wherein the inaccuracy function measures a difference between actual object voltage-current characteristics and an electrical model with estimated intrinsic parameters for a period of time, wherein a particle with a lowest inaccuracy value is considered a best particle of the set of particles, and wherein a particle with a highest inaccuracy value is considered a worst particle of the set of particles;

ii. generating a replacement particle by generating and injecting a perturbation into the best particle;

iii. evaluating an inaccuracy value of the replacement particle using the inaccuracy function;

iv. if the replacement particle has a lower inaccuracy value than the best particle, replacing the best particle with the replacement particle in the set of particles, or else replacing the worst particle with the replacement particle in the set of particles; and

v. updating the velocity and position of each particle in the set of particles; and

c. determining state of charge, cold cranking ampere, and internal resistance of the electrical model of the object based on the set of particles.

18. The method for testing objects of claim 12, wherein determining an inaccuracy value of each particle is determined by evaluating function

19. The method for testing objects of claim 12, wherein state of charge (“

SOC”

) at time t is determined by evaluating