AC CURRENT CONTROL OF MOBILE BATTERY CHARGERS

• US 20120091953A1
• Filed: 10/13/2010
• Published: 04/19/2012
• Est. Priority Date: 10/13/2010
• Status: Active Grant

• Current Assignee: Tesla Inc.
• Original Assignee: Tesla Motors Incorporated (Tesla Inc.)
• Inventors: Paryani, Anil, Nergaard, Troy A., Baglino, Andrew
• Granted Patent: US 8,638,063 B2
• Time in Patent Office: Days
• US Class Current: 320/109
• CPC Class Codes: B60L 53/63 in response to network capacity
• CPC Class Codes: B60L 55/00 Arrangements for supplying energy stored within a vehicle to a power network, i.e. vehicle-to-grid [V2G] arrangements
• CPC Class Codes: H01M 10/44 Methods for charging or discharging circuits for charging H02J7/00
• CPC Class Codes: H01M 10/46 Accumulators structurally combined with charging apparatus circuits for charging H02J7/00
• CPC Class Codes: H01M 10/48 Accumulators combined with arrangements for measuring, testing or indicating the condition of cells, e.g. the level or density of the electrolyte constructional details of current conducting connections for detecting conditions inside cells or batteries, e.g. details of voltage sensing terminals, H01M50/569
• CPC Class Codes: H02J 7/007 Regulation of charging or discharging current or voltage
• CPC Class Codes: H02J 7/04 Regulation of charging current or voltage
• CPC Class Codes: Y02E 60/00 Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y02T 90/12 Electric charging stations
• CPC Class Codes: Y02T 90/14 Plug-in electric vehicles
• CPC Class Codes: Y02T 90/16 Information or communication technologies improving the operation of electric vehicles
• CPC Class Codes: Y04S 10/126 the energy generation units being or involving electric vehicles [EV] or hybrid vehicles [HEV], i.e. power aggregation of EV or HEV, vehicle to grid arrangements [V2G]

Abstract

A charging system and method that improves utilization of available AC power during onboard charging of energy storage systems of electric vehicles. An onboard charging method for an energy storage system of an electric vehicle, the method using an AC power source, includes a) establishing a maximum DC charging current for the energy storage system responsive to a control signal indicating real-time available current/power from the AC source; and b) controlling a charging system to provide an actual DC charging current, up to the maximum DC charging current, to the energy storage system.

Claims

1. An onboard charging method for an energy storage system of an electric vehicle, the method using an AC power source, the method comprising the steps of:

a) establishing a maximum DC charging current for the energy storage system responsive to a control signal indicating real-time available current; and

b) controlling a charging system to provide an actual DC charging current, up to said maximum DC charging current, to the energy storage system.

2. An onboard charging method for an energy storage system of an electric vehicle, the method using an AC power source, the method comprising the steps of:

a) evaluating a first process control loop to set a reference DC current responsive to a difference between a DC target voltage for the energy storage system and a voltage feedback for the energy storage system, said first process control loop setting said reference DC current at a value ranging between about a target discharging current and about a target charging current for the energy storage system; and

b) evaluating a second process control loop to set a control signal responsive to a difference between said reference DC current and a generated DC current provided to the energy storage system for charging, said second process control loop setting said control signal at a value ranging between a maximum DC discharging current and a maximum DC charging current derived from an available real-time AC current; and

c) controlling a charger onboard the electric vehicle responsive to said control signal to produce said generated DC current.

3. An electronic system for charging an energy storage system of an electric vehicle with charging using an AC power source, comprising:

an energy access system, coupled to the AC energy source, producing an input AC current;

a charger, coupled to said energy access system, for producing an actual DC charging current responsive to a control signal;

a controller configured to adjust said actual DC charging current based upon said input AC current and a difference between a target DC charging current and said actual DC charging current.

4. An electronic system for charging an energy storage system of an electric vehicle with charging using an AC power source, comprising:

an energy access system, coupled to the AC energy source, producing an input AC current;

a charger, coupled to said energy access system, for producing an actual DC charging current responsive to a control signal;

a voltage sensor that measures a voltage level of the energy storage system;

a current sensor that measures a magnitude of said actual DC charging current applied to charging the energy storage system; and

a controller, coupled to said current sensor, wherein said controller is configured to adjust said actual DC charging current based upon a maximum current for said input AC current, a difference between said voltage level and a preset maximum voltage level target of the energy storage system, and a difference between a target DC charging current and said actual DC charging current.

5. An onboard charging method for an energy storage system of an electric vehicle, the method using an AC power source, the method comprising the steps of:

a) establishing a maximum DC charging current for the energy storage system responsive to a control signal indicating real-time available power; and

b) controlling a charging system to provide an actual DC charging current, up to said maximum DC charging current, to the energy storage system.

6. An onboard charging method for an energy storage system of an electric vehicle, the method using an AC power source, the method comprising the steps of:

a) evaluating a first process control loop to set a reference DC current responsive to a difference between a DC target voltage for the energy storage system and a maximum DC voltage for the energy storage system, said first process control loop setting said reference DC current at a value ranging between about a target discharging current and about a target charging current for the energy storage system; and

b) evaluating a second process control loop to set a control signal responsive to a difference between said reference DC current and a generated DC current provided to the energy storage system for charging, said second process control loop setting said control signal at a value ranging between a maximum DC discharging current and a maximum DC charging current derived from an available real-time AC power; and

c) controlling a charger onboard the electric vehicle responsive to said control signal to produce said generated DC current.

7. An electronic system for charging an energy storage system of an electric vehicle with charging using an AC power source, comprising:

an energy access system, coupled to the AC energy source, producing an input AC power;

a charger, coupled to said energy access system, for producing an actual DC charging current responsive to a control signal from said input AC power;

a controller configured to adjust said actual DC charging current based upon a maximum for said input AC power and a difference between a target DC charging current and said actual DC charging current.

8. An electronic system for charging an energy storage system of an electric vehicle with charging using an AC power source, comprising:

an energy access system, coupled to the AC energy source, producing an input AC power;

a charger, coupled to said energy access system, for producing an actual DC charging current responsive to a control signal;

a voltage sensor that measures a voltage level of the energy storage system;

a current sensor that measures a magnitude of said actual DC charging current applied to charging the energy storage system; and

a controller, coupled to said current sensor, wherein said controller is configured to adjust said actual DC charging current based upon a maximum for said input AC power,

a difference between said voltage level and a preset maximum voltage level target of the energy storage system, and a difference between a target DC charging current and said actual DC charging current.