US 12,218,506 B2
Systems and methods for sliding mode control enabled hybrid energy storage
Ali Jafarian Abianeh, Lafayette, LA (US); and Farzad Ferdowsi, Lafayette, LA (US)
Assigned to University of Louisiana at Lafayette, Lafayette, LA (US)
Filed by University of Louisiana at Lafayette, Lafayette, LA (US)
Filed on Aug. 5, 2022, as Appl. No. 17/881,912.
Claims priority of provisional application 63/229,704, filed on Aug. 5, 2021.
Prior Publication US 2023/0047077 A1, Feb. 16, 2023
Int. Cl. H02J 3/38 (2006.01); H02J 3/00 (2006.01); H02J 7/00 (2006.01); H02J 7/34 (2006.01); H02J 7/35 (2006.01)
CPC H02J 3/381 (2013.01) [H02J 3/007 (2020.01); H02J 3/388 (2020.01); H02J 7/0063 (2013.01); H02J 7/00711 (2020.01); H02J 7/00712 (2020.01); H02J 7/345 (2013.01); H02J 7/35 (2013.01); H02J 2207/50 (2020.01); H02J 2300/26 (2020.01)] 4 Claims
OG exemplary drawing
 
1. A method for controlling an islanded direct current microgrid comprising:
connecting one or more loads to a voltage bus of the microgrid;
connecting a PV unit to the voltage bus, wherein the PV unit comprises a plurality of PV cells, a solar converter, a DC voltage bus, at least one battery pack, a hybrid energy storage system (HESS) unit, a supercapacitor module, and two or more loads;
integrating a hybrid energy storage system (HESS unit) into the microgrid, wherein such HESS unit comprises:
a current rate limiter;
connection to a battery;
connection to a supercapacitor module; and
connection to the voltage bus;
regulating a current of the battery;
regulating a current of the supercapacitor module, wherein a supercapacitor current provides excess power demand based on different loading conditions to an islanded direct current microgrid;
controlling the supercapacitor module, wherein the supercapacitor module is connected in parallel formation to a direct current bus voltage control loop;
detecting a voltage drop of the supercapacitor module to a value lower than a minimum threshold voltage for said supercapacitor module;
providing a current setpoint for the supercapacitor module, wherein said current setpoint is determined by offsetting a maximum setpoint current value from both an actual current value of the supercapacitor module and a setpoint current value of the battery; and
saturating a capacity of a reference hybrid energy storage system current, wherein the battery current reference always remains saturated during a charging process, and wherein the supercapacitor is charged with excess power generated by the battery as compared with a demanded load power.