Solar panel power management system and method

• US 8,269,374 B2
• Filed: 03/04/2011
• Issued: 09/18/2012
• Est. Priority Date: 03/04/2010
• Status: Active Grant

• Current Assignee: Damian D.E. Caires
• Original Assignee: Damian D.E. Caires
• Inventors: De Caires, Damian
• Primary Examiner(s): RUTLAND WALLIS, MICHAEL
• Application Number:
  US13/040,559
• Publication Number:
  US 20110273019A1
• Time in Patent Office: 564 Days
• Field of Search: 307/66, 307/64, 307/82
• US Class Current: 307/82
• CPC Class Codes: H02J 2300/24 of photovoltaic origin
• CPC Class Codes: H02J 3/381 Dispersed generators
• CPC Class Codes: H02J 3/46 Controlling of the sharing of output between the generators, converters, or transformers
• CPC Class Codes: H02J 7/35 with light sensitive cells
• CPC Class Codes: H02J 9/06 with automatic change-over , e.g. UPS systems
• CPC Class Codes: Y02B 10/70 Hybrid systems, e.g. uninterruptible or back-up power supplies integrating renewable energies
• CPC Class Codes: Y02E 10/56 Power conversion systems, e.g. maximum power point trackers

Abstract

A controlled switching arrangement from a first mode of power transfer, in which an ecological power source (EPS) directly charges a battery during times of a utility power outage to a second mode of power transfer in which the EPS output is fully delivered through a grid-interactive inverter so as to provide A.C. power to the grid power connection. A single switching operation switches between power transfer modes as a function of an availability of the utility power output over the grid power connection such that a percentage of utility power output is supplied directly to the battery in the second mode so as to maintain the battery in a charged condition for use during the times of the utility power outage, and an off-grid inverter converts charge stored in the battery into A.C. power when the controller is switched to the first mode of power transfer.

Claims

1. A method for balancing respective outputs of an ecological power source (“

EPS”

), a grid power connection, and a D.C. battery so as to minimize conversion losses, comprising;

providing a first mode of power transfer in which the EPS output directly charges the D.C. battery during times of a utility power outage;

providing a second mode of power transfer in which the EPS output is fully delivered through a grid-interactive inverter so as to provide A.C. power to the grid power connection;

controlling in a single switching operation the first and second modes of power transfer as a function of an availability of the utility power output over the grid power connection,

the single switching operation including the step of;

switching an interlocked arrangement of a grid-interactive inverter and an off-grid inverter so that when one of the grid-interactive and off-grid inverters is turned on the other is turned off, wherein the EPS is switched from a straight-to-A.C. inverter connection via the grid-interactive inverter while in the second mode of power transfer to a straight-to-D.C. connection to charge the battery while in the first mode of power transfer in order to maintain a one-step conversion in both the first and second modes of power transfer;

wherein a percentage of utility power output over the grid power connection is supplied directly to the battery when the controller is switched to the second mode of power transfer so as to utilize the output of the grid power connection as a source to maintain the battery in a charged condition for use during the times of the utility power outage, and

wherein an off-grid inverter converts charge stored in the battery into A.C. power when the controller is switched to the first mode of power transfer; and

trickle charging the battery through the grid power connection in the second mode of power transfer.

2. The method of claim 1, wherein a majority of the utility power output over the grid power connection is supplied to a load when the controller is switched to the second mode of power transfer.

3. The method of claim 1, wherein the off-grid inverter is configured with high-capacitance as compared to the grid-interactive inverter so as to accommodate surges in the load.

4. The method of claim 1, wherein the percentage of utility power output over the grid power connection that is being supplied directly to the battery when the controller is switched to the second mode of power transfer is variable.

5. The method of claim 4, wherein a remainder of the utility power output over the grid power connection is being supplied to one or more loads when the controller is switched to the second mode of power transfer.

6. The method of claim 5, wherein, in the second mode of power transfer, all of the output from the EPS is directed to the grid-interactive inverter for delivery to the grid power connection.

7. The method of claim 1, wherein the battery is charged by way of the grid power connection so long as there is utility power output over the grid power connection.

8. The method of claim 1, wherein the controlling step automatically switches between the first and second modes of power transfer in response to a detected interruption of the utility power output over the grid power connection.

9. The method of claim 1, wherein each of the power transfer modes has a one-step conversion of the output of the EPS into A.C. power such that:

energy from the EPS is transferred to the grid power connection after inversion by a grid-interactive inverter free of any battery storage when in the first mode of power transfer, and

energy from the EPS is transferred to a load after inversion by an off-grid inverter when in the second mode of power transfer.

10. The method of claim 1, wherein the EPS is a D.C. source.

11. The method of claim 1, wherein the EPS is a wind collector, a solar energy collector, or both.

12. The method of claim 1, wherein the EPS comprises an array of solar energy collectors, and wherein each collector in the array is controlled by the controlling step using a single switching operation.

13. The method of claim 1, wherein the trickle charging occurs only when an AC-to-DC charger monitors a loss in battery potential due to standby losses.