Communication-free charge controller for electric vehicles

Patent metadata

Field	Value
Publication number	US-11117487-B2
Application number	US-201916408005-A
Country	US
Kind code	B2
Filing date	May 9, 2019
Priority date	May 9, 2019
Publication date	Sep 14, 2021
Grant date	Sep 14, 2021

Abstract

An electric vehicle charge controller and charging method for controlling a charging rate for a battery of an electric vehicle is presented. The battery receives charge via a node connected to a power distribution source. The charge controller receiving a nodal voltage measurement for voltage at the node, receiving a value of electric power at the node, and determining a change in the electric power value based on a previous electric power value. When the change in electric power is greater than a load change threshold, the charge controller determines an estimate of voltage-to-load sensitivity. The charge controller determines the charging rate of the electric vehicle based on the nodal voltage, the determined voltage-to-load sensitivity, and a state of charge of the at least one battery, and controls the charging rate for the at least one battery in accordance with the determined charging rate.

First claim

The invention claimed is:

1. An autonomous charge controller for controlling a charging rate for at least one battery of an electric vehicle without communication with a power distribution grid, the at least one battery receiving charge via a node connected to the power distribution grid, the charge controller comprising:
circuitry configured to
receive a nodal voltage measurement for voltage at the node,
receive a value of electric power at the node,
determine a change in the electric power value based on a previous power value at a previous time,
when the change in electric power is greater than a load change threshold, determine an estimate of voltage-to-load sensitivity,
determine the charging rate of the electric vehicle based on the nodal voltage, the determined voltage-to-load sensitivity, and a state of charge of the at least one battery, and
control the charging rate for the at least one battery in accordance with the determined charging rate.

2. The charge controller of claim 1 , wherein the circuitry is configured to determine the estimate of the voltage-to-load sensitivity based on a complementary relationship between the nodal voltage and voltage sensitivity at the node.

3. The charge controller of claim 2 , wherein the complementary relationship used by the circuitry to determine the estimate of the voltage-to-load sensitivity is a ratio of a change in the nodal voltage and the change in electric power with respect to a previous periodic interval.

4. The charge controller of claim 1 , further comprising:
a voltage measurement device for measuring the nodal voltage;
a current measurement device for measuring the current; and
a state of charge measurement device for detecting the state of charge of the at least one battery.

5. The charge controller of claim 1 , wherein the load change threshold is 10% of the power value before the power change.

6. The charge controller of claim 1 , wherein the circuitry is further configured to
determine the charging rate of the electric vehicle based on the measured nodal voltage, the voltage-to-load sensitivity at the previous periodic interval, and the battery state of charge when the determined estimate of the voltage-to-load sensitivity is negative.

7. The charge controller of claim 1 , wherein the circuitry is further configured to
receive a battery capacity, the battery state of charge and departure time,
determine an uncharged battery capacity using the battery capacity and the battery state of charge, and
determine charging rate of the electric vehicle based on the uncharged battery capacity and the departure time.

8. The charge controller of claim 1 , wherein the circuitry is further configured to limit the charging rate to not to exceed a maximum charging rate.

9. The charge controller of claim 1 , wherein the circuitry is further configured to charge the electric vehicle at an increased rate based on an exponential function when the state of charge is below a predetermined level.

10. The charge controller of claim 1 , wherein the circuitry is configured to determine the charging rate of the electric vehicle EP(t) as follows

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Assignees

• Univ King Fahd Pet & Minerals

Inventors

• Al-Awami Ali Taleb T
• Shafiq Saifullah

Classifications

• G01R31/382

  Arrangements for monitoring battery or accumulator variables, e.g. SoC · CPC title

• Y02T90/12

  Electric charging stations · CPC title

• B60L53/665 Primary

  Methods related to measuring, billing or payment · CPC title

• B60L53/16

  Connectors, e.g. plugs or sockets, specially adapted for charging electric vehicles · CPC title

• Y02T10/70

  Energy storage systems for electromobility, e.g. batteries · CPC title