Systems and methods for decreasing peak energy consumption of a power consumer using vehicle battery capacity

• US 9,509,159 B2
• Filed: 03/20/2014
• Issued: 11/29/2016
• Est. Priority Date: 03/20/2014
• Status: Expired due to Fees

• Current Assignee: Nissan Motor Co., Ltd.
• Original Assignee: Nissan North America Incorporated (Nissan Motor Co., Ltd.)
• Inventors: Yonetani, Shinsuke
• Primary Examiner(s): Grant, Robert
• Assistant Examiner(s): O'NEILL-BECERRIL, HARRY
• Application Number:
  US14/220,646
• Publication Number:
  US 20150268304A1
• Time in Patent Office: 985 Days
• Field of Search: 320/134
• US Class Current: 1/1
• CPC Class Codes: H02J 3/322 the battery being on-board an electric or hybrid vehicle, e.g. vehicle to grid arrangements [V2G], power aggregation, use of the battery for network load balancing, coordinated or cooperative battery charging

Abstract

Systems and methods of reducing peak energy consumption of a power consumer comprise preprogramming an actual consumption line based on expected power usage, and determining the battery'"'"'s connection time, required departure time, required departure energy and connection energy. A charge rate and a discharge rate are preselected, and a first charge energy level is calculated from the peak energy level less the discharge rate and the charge rate. A connection time of the battery when the battery is connected to the power consumer, a connection energy of the battery at the connection time, a required departure time of the battery, a required departure energy are determined. A power exchange curve is determined during a connection period between the connection time and the required departure time configured to minimize an expected peak energy level.

Claims

1. A method performed by a processor for decreasing peak energy consumption of a power consumer during power exchange with a battery of a vehicle, the method comprising:

preprogramming an actual consumption line based on expected power usage, the actual consumption line having a peak energy consumption;

determining a connection time of the battery when the battery is connected to the power consumer, a connection energy of the battery at the connection time, a required departure time of the battery, a required departure energy;

calculating a power exchange curve during a connection period between the connection time and the required departure time configured to minimize an expected peak energy consumption while securing the required departure energy by the required departure time, wherein calculating the power exchange curve comprises;

preselecting a charge rate and a discharge rate;

calculating a first charge energy level from the peak energy consumption less the discharge rate and the charge rate;

calculating a first charge period from the connection time and a first time the first charge energy line crosses the actual consumption line;

calculating a second charge period from the required departure time and a second time the first charge energy line crosses the actual consumption line;

calculating a first charge energy at an end of the first charge period using the charge rate;

calculating a second charge energy at a start of the second charge period using the charge rate;

if the first charge energy is greater than the second charge energy, calculating a discharge energy level from the peak energy consumption less the discharge rate; and

calculating a revised discharge rate and a discharge period corresponding to the discharge energy level;

charging the battery during the first charge period at the charge rate; and

charging the battery during the second charge period at the charge rate.

2. The method of claim 1, wherein calculating the revised discharge rate comprises:

calculating a discharge period between a first time and a second time the discharge energy level crosses the actual consumption line;

calculating the revised discharge rate from the discharge period and a difference between the first charge energy and the second charge energy.

3. The method of claim 2 further comprising:

discharging the battery during the discharge period at the revised discharge rate; and

idling power exchange during idle periods, idle periods occurring between the first charge period and the discharge period and between the discharge period and the second charge period.

4. The method of claim 1, wherein, if the first charge energy is less than the second charge energy:

calculating a second charge energy level from the peak energy consumption less the charge rate; and

calculating extended charge periods based on the second charge energy level.

5. The method of claim 4, wherein calculating extended charge periods comprises:

calculating a third charge period from the end of the first charge period to a first time the second charge energy level crosses the actual consumption line;

calculating a third charge energy from the charge rate and the third charge period;

calculating a fourth charge period from a second time the second charge energy level crosses the actual consumption line to a start of the second charge period; and

calculating a fourth charge energy from the charge rate and the fourth charge period.

6. The method of claim 5, wherein if the third charge energy is greater than the fourth charge energy, selecting an idle energy between the third charge energy the fourth charge energy;

calculating a fifth charge period from an end of the first charge period to a time when the idle energy is reached at the preselected charge rate;

calculating a sixth charge period;

setting an idle period between the fifth charge period and the sixth charge period; and

if the third charge energy is less than the fourth charge energy, minimizing the expected peak energy consumption.

7. The method of claim 6 further comprising:

charging the battery from the connection time through the fifth charge period at the charge rate;

idling the battery through the idle period; and

charging the battery through the sixth charge period to the required departure time at the charge rate.

8. The method of claim 6, wherein minimizing the expected peak energy consumption comprises:

calculating a revised charge rate to charge from the third charge energy to the fourth charge energy, and plotting a first charge curve;

determining an idle energy between the third charge energy and the fourth charge energy so that a peak energy consumption is minimized, determining a fifth charge period from the end of the third charge period until the idle energy is reached, determining a sixth charge period prior to the start fourth charge period based on the idle energy and plotting a second charge curve; and

selecting one of the first charge curve and the second charge curve that minimizes the expected peak energy consumption.

9. The method of claim 8, wherein if the first charge curve is selected, the method further comprises:

charging the battery at the charge rate from the connection time through the third charge period;

charging the battery at the revised charge rate from the third charge period to the fourth charge period; and

charging the battery at the charge rate through the fourth charge period to the required departure time.

10. The method of claim 8, wherein if the second charge curve is selected, the method further comprises:

charging the battery at the charge rate from the connection time through the fifth charge period;

idling the battery from the end of the fifth charge period to the start of the sixth charge period; and

charging the battery at the charge rate through the sixth charge period to the required departure time.

11. The method of claim 8, wherein the peak energy consumption during the fifth charge period equals a peak energy consumption during the sixth charge period.

12. The method of claim 1, wherein determining one or both of the required departure time and the required departure energy comprises receiving a user input.

13. The method of claim 1, wherein the required departure energy is a default departure energy.

14. A system for decreasing peak energy consumption of a power consumer comprising:

a system controller preprogramed with an actual consumption line based on expected power usage, the actual consumption line having an actual peak energy consumption; and

a vehicle charger in communication with the system controller to receive instructions on charging and discharging from the system controller, wherein the system controller is operable to;

determine a connection time of the battery when the battery is connected to the power consumer, a connection energy of the battery at the connection time, a required departure time of the battery, a required departure energy; and

calculate a power exchange curve during a connection period between the connection time and the required departure time configured to minimize an expected peak energy consumption while securing the required departure energy by the required departure time, wherein, when calculating the power exchange curve, the system controller is further operable to;

preselect a charge rate and a discharge rate;

calculate a first charge energy level from the peak energy consumption less the discharge rate and the charge rate;

calculate a first charge period from the connection time and a first time the first charge energy line crosses the actual consumption line;

calculate a second charge period from the required departure time and a second time the first charge energy line crosses the actual consumption line;

calculate a first charge energy at an end of the first charge period using the charge rate;

calculate a second charge energy at a start of the second charge period using the charge rate;

if the first charge energy is greater than the second charge energy, calculate a discharge energy level from the peak energy consumption less the discharge rate; and

calculate a revised discharge rate and a discharge period corresponding to the discharge energy level, wherein the vehicle charger discharges the battery at the revised discharge rate.

15. The system of claim 14, wherein, when calculating the revised discharge rate, the system controller is further operable to:

calculate a discharge period between a first time and a second time the discharge energy level crosses the actual consumption line;

calculate the revised discharge rate from the discharge period and a difference between the first charge energy and the second charge energy; and

provide instructions to;

charge the battery during the first charge period at the charge rate;

discharge the battery during the discharge period at the revised discharge rate;

charge the battery during the second charge period at the charge rate; and

idle power exchange during idle periods, idle periods occurring between the first charge period and the discharge period and between the discharge period and the second charge period.

16. The system of claim 14, wherein, if the first charge energy is less than the second charge energy, the system controller is further operable to:

calculate a second charge energy level from the peak energy consumption less the charge rate; and

calculate extended charge periods based on the second charge energy level by;

calculating a third charge period from the end of the first charge period to a first time the second charge energy level crosses the actual consumption line;

calculating a third charge energy from the charge rate and the third charge period;

calculating a fourth charge period from a second time the second charge energy level crosses the actual consumption line to a start of the second charge period; and

calculating a fourth charge energy from the charge rate and the fourth charge period.

17. The system of claim 16, wherein if the third charge energy is greater than the fourth charge energy, the system controller is further operable to select an idle energy between the third charge energy the fourth charge energy;

calculate a fifth charge period from an end of the first charge period to a time when the idle energy is reached at the preselected charge rate;

calculate a sixth charge period;

set an idle period between the fifth charge period and the sixth charge period; and

if the third charge energy is less than the fourth charge energy, minimize the expected peak energy consumption.

18. The system of claim 17, wherein, when minimizing the expected peak energy consumption, the system controller is further operable to:

calculate a revised charge rate to charge from the third charge energy to the fourth charge energy, and plot a first charge curve;

determine an idle energy between the third charge energy and the fourth charge energy so that a peak energy consumption is minimized, determine a fifth charge period from the end of the third charge period until the idle energy is reached, determine a sixth charge period prior to the start of the fourth charge period based on the idle energy and plotting a second charge curve; and

select one of the first charge curve and the second charge curve that minimizes the expected peak energy consumption.