Bi-directional optimizers for battery storage systems with galvanic isolation
AssigneeAlencon Acquisition Co., LLC.
InventorsOleg S. Fishman, Zekeriya Dereli, David Luksenberg, Hanan Fishman
Life of this patent
Estimating the term…
Abstract
Equalization of the state of health of multiple serial strings of battery cells connected in parallel to a common direct current bus in an energy storage system utilized with a utility-sized renewable energy system or other system where optimum operational battery health is a requirement, and in particular is provided by a separate bi-directional DC-to-DC converter in each serial string that controls the charge and discharge of the multiple serial strings of battery cells to maximize efficiency of the stored energy and also provides galvanic isolation between the direct current bus and the multiple serial strings of battery cells.
Claims20
An optimized battery state of health sustaining system for an electrical energy storage intermittently receiving a DC power from an alternative DC energy source having a rated output of at least 100 kilowatts and supplying a controlled DC power to an alternating current output of a DC-to-AC inverter and a transformation network via a common DC bus to an electrical grid, the optimized battery state of health sustaining system comprising:
- a plurality of bi-directional galvanically isolated current optimizers, each one of the plurality of bi-directional galvanically isolated current optimizers having a pair of bus terminals connected to the common DC bus and a pair of battery terminals connected to one of a plurality of series connected strings of battery cells, each one of the plurality of series connected strings of battery cells contained in a separate battery rack whereby each one of the plurality of series connected strings of battery cells is galvanically isolated from the common DC bus;
- and
- an energy storage system controller further comprising an optimizer controller, in communication with each one of the plurality of bi-directional galvanically isolated current optimizers for an independent charging control or an independent discharging control of a battery current in each one of the plurality of series connected strings of battery cells.
A method of sustaining the optimized battery state of health for an electrical energy storage intermittently receiving a DC power from an alternative DC energy source having a rated output of at least 100 kilowatts and supplying a controlled DC power to an alternating current output of a DC-to-AC inverter and a transformation network via a common DC bus to an electrical grid, the method comprising:
- providing a dedicated one of a plurality of bi-directionally galvanically isolated current optimizers between the common DC bus and each one of a plurality of series connected strings of battery cells, each one of the plurality of series connected strings of battery cells contained in a separate battery rack to galvanically isolate each one of the plurality of series connected strings of the battery cells from the common DC bus;
- and
- independently controlling a battery charge current or a battery discharging current for each one of the plurality of series connected strings of battery cells.
An optimized battery state of health sustaining system for an electrical energy storage intermittently receiving a DC power from an alternative DC energy source having a rated output of at least 100 kilowatts and supplying a controlled DC power to an alternating current output of a DC-to-AC inverter and a transformation network via a common DC bus to an electrical grid, the optimized battery state of health sustaining system comprising:
- a plurality of bi-directional galvanically isolated current optimizers, each one of the plurality of bi-directional galvanically isolated current optimizers comprising at least one galvanically isolated DC-to-DC converter and having a pair of bus terminals connected to the common DC bus and a pair of battery terminals connected to one of a plurality of series connected strings of battery cells, each one of the plurality of series connected strings of battery cells contained in a separate battery rack comprising a plurality of battery modules for a distributed containment of each one of the plurality of series connected strings of battery cells whereby each one of the plurality of series connected strings of battery cells is galvanically isolated from the common DC bus;
- a separate charge optimizer processor integrated in each one of the plurality of bi-directional galvanically isolated current optimizers, the separate charge optimizer processor in communication with an energy storage system controller and a battery management system;
- and
- the energy storage system controller further comprising an optimizer controller, the optimizer controller in communication with each one of the plurality of bi-directional galvanically isolated current optimizers for an independent charging control or an independent discharging control of a battery current in each one of the plurality of series connected strings of battery cells.
Dependencies are inferred from the claim text.