Adaptive charge control for transport climate control applications

1 . A method for operating a power system that is powering a load while the power system is connected to an external power source, the method comprising:

determining a charger of the power system is connected to the external power source and the charger is enabled;

monitoring a rechargeable energy storage source (RESS) state of charge (SoC) of a RESS of the power system;

monitoring a RESS current;

a RESS management system (RMS) modulating a charger current from the charger to the RMS, wherein the RMS includes a high voltage power distribution unit configured to distribute electrical power passing through the RMS;

the RMS modulating RESS current, the RESS current being either (i) provided by the RMS to the RESS and configured to charge the RESS of the power system, or (ii) being supplied by the RESS to the RMS and configured to power the load; and

the RMS modulating a load current supplied to the load from the RMS via the charger or the RESS.

2 . The method of claim 1 , further comprising:

determining the RESS SoC is greater than or equal to the desired RESS SoC threshold; and

modulating the charger current from the charger to the RMS to supply approximately 0 A for charging the RESS upon determining the RESS SoC is greater than or equal to the desired RESS SoC threshold.

3 . The method of claim 1 , further comprising:

the RESS current discharging while the RESS SoC is below the desired RESS SoC threshold; and

upon the RESS current discharging while the RESS SoC is below the desired RESS SoC threshold, instructing the charger to increase the charger current output to the RMS.

4 . The method of claim 1 , further comprising instructing the charger to decrease the charger current from the charger to the RMS upon the charger current exceeding a charger threshold.

5 . The method of claim 1 , further comprising instructing the charger to decrease the charger current upon the RESS current exceeding a RESS current threshold.

6 . The method of claim 1 , wherein the RESS comprises a lithium-ion battery.

7 . The method of claim 1 , wherein modulating the charger current includes increasing or decreasing the charger current output by a predetermined interval.

8 . A power system for powering a load while being connected to an external power source, the power system comprising:

a charger configured to connect the external power source to a rechargeable energy storage source management system (RMS);

the RMS: a) configured to modulate a charger current from the charger to the RMS, the charger current being configured to provide electrical power to the power system; b) configured to modulate a rechargeable energy storage source (RESS) current configured to charge or discharge a RESS, the RESS current being either (i) provided by the RMS to the RESS and configured to charge the RESS of the power system, or (ii) being supplied by the RESS to the RMS and configured to power the load; and c) configured to modulate a load current supplied to the load from the RMS via the charger or the RESS;

the RESS configured to provide power to the load; and

a controller configured to:

determine that the charger is connected to the external power source and configured to determine that the charger is enabled; and

monitor a RESS state of charge (SoC) of a RESS;

the RMS configured to

monitor the RESS current,

wherein the RMS includes a high voltage power distribution unit configured to distribute electrical power passing through the RMS.

9 . The power system of claim 8 , wherein the controller is configured to:

determine the RESS SoC is greater than or equal to the desired RESS SoC threshold; and

modulate the charger current from the charger to the RMS to supply approximately 0 A for charging the RESS upon determining the RESS SoC is greater than or equal to the desired RESS SoC threshold.

10 . The power system of claim 8 , wherein the controller is configured to determine that the RESS SoC is below the desired RESS SoC threshold, and

wherein the controller is configured to, upon the RESS current discharging while the RESS SoC is below the desired RESS SoC threshold, instruct the charger to increase the charger current output to the RMS.

11 . The power system of claim 8 , wherein the controller is configured to instruct the charger to decrease the charger current from the charger to the RMS upon the charger current exceeding a charger current threshold.

12 . The power system of claim 8 , wherein the controller is configured to instruct the charger to decrease the charger current upon the RESS current exceeding a RESS current threshold.

13 . The power system of claim 8 , wherein the RESS comprises a lithium-ion battery.

14 . The power system of claim 8 , wherein the controller is configured to modulate the charger current by increasing or decreasing the charger current output by a calculated amount.

15 . The power system of claim 8 , wherein the load is a transport climate control system.

16 . The method of claim 1 , wherein modulating the charger current, the RESS current, and the load current includes:

determining that the charger current from the charger to the RMS is not below a charger current threshold;

upon determining that the charger current is not below the charger current threshold:

decreasing a charger current output when a) a current flowing from the charger to a RESS is greater than a RESS threshold, and b) when the RESS SoC is greater than or equal to a desired RESS SoC, and

maintaining the charger current output when either a) the RESS is not greater than the RESS threshold, or b) the RESS SoC is less than the desired RESS SoC.

17 . The method of claim 1 , wherein modulating the charger current, the RESS current, and the load current includes:

determining that the charger current is below the charger current threshold;

upon determining that the charger current is below the charger current threshold:

decreasing the charger current when either a) (i) the RESS is not discharging and (ii) the current flowing from the charger to the RESS is less than a charging current threshold, or b) (i) the RESS is not discharging, (ii) the current flowing from the charger to the RESS is less than the charging current threshold, and (iii) the RESS SoC is greater than or equal to the desired RESS SoC,

maintaining the charger current output when a) the RESS is discharging, and b) the RESS SoC is greater than or equal to the desired RESS SoC, and

increasing the charger current when either a) (i) the RESS is discharging and (ii) the RESS SoC is greater than or equal to the desired RESS SoC, or b) (i) the RESS is not discharging, (ii) the current flowing from the charger to the RESS is less than the charging current threshold, and (iii) the RESS SoC is greater than or equal to the desired RESS SoC.

18 . The power system of claim 8 , wherein the controller is configured to:

determine that a charger current from the charger to the RMS is not below a charger current threshold; and

upon determining that the charger current is not below the charger current threshold:

instruct the charger to decrease a charger current output when a) a current flowing from the charger to a RESS is greater than a RESS threshold, and b) when the RESS SoC is greater than or equal to a desired RESS SoC, and

instruct the charger to maintain the charger current output when either a) the RESS is not greater than the RESS threshold, or b) the RESS SoC is less than the desired RESS SoC.

19 . The power system of claim 8 , wherein the controller is configured to:

determine that the charger current from the charger to the RMS is below a charger current threshold; and

upon determining that the charger current is below the charger current threshold:

instructing the charger to decrease the charger current when either a) (i) the RESS is not discharging and (ii) the current flowing from the charger to the RESS is less than a charging current threshold, or b) (i) the RESS is not discharging, (ii) the current flowing from the charger to the RESS is less than the charging current threshold, and (iii) the RESS SoC is greater than or equal to the desired RESS SoC,

instructing the charger to maintain the charger current output when a) the RESS is discharging, and b) the RESS SoC is greater than or equal to the desired RESS SoC, and

instructing the charger to increase the charger current when either a) (i) the RESS is discharging and (ii) the RESS SoC is greater than or equal to the desired RESS SoC, or b) (i) the RESS is not discharging, (ii) the current flowing from the charger to the RESS is less than the charging current threshold, and (iii) the RESS SoC is greater than or equal to the desired RESS SoC.