METHOD FOR CONTROLLING AN ENERGY STORAGE SYSTEM TO INFLUENCE THE BALANCING OF THE SYSTEM
An energy storage system comprises an energy storage node that includes a plurality of battery storage elements and a control subsystem to receive battery data from the battery storage elements. The energy storage system further includes a power conversion system (PCS) and a control system coupled to the energy storage node and the PCS. The control system, the control subsystem, or both are configured to: receive or store battery charge and discharge characteristics of the battery storage elements during a plurality of operating conditions of the battery storage elements, the PCS, or both; and run the battery storage elements of the energy storage node at one or more selected operating conditions of the plurality of operating conditions based on the battery charge and discharge characteristics to reduce an imbalance in state of charge among the battery storage elements of the energy storage node.
1 . An energy storage system, comprising:
an energy storage node, including:
a plurality of battery storage elements, and
a control subsystem to receive battery data from the battery storage elements;
a power conversion system (PCS); and
a control system coupled to the energy storage node and the PCS;
wherein the control system, the control subsystem, or both are configured to:
receive or store battery charge and discharge characteristics of the battery storage elements during a plurality of operating conditions of the battery storage elements, the PCS, or both; and
run the battery storage elements of the energy storage node at one or more selected operating conditions of the plurality of operating conditions based on the battery charge and discharge characteristics to reduce an imbalance in state of charge among the battery storage elements of the energy storage node.
2 . The energy storage system of claim 1 , wherein the control system, the control subsystem, or both are configured to determine states of charge of each of the battery storage elements of the energy storage node from the battery data during the one or more selected operating conditions.
3 . The energy storage system of claim 2 , wherein the control system, the control subsystem, or both are configured to:
identify a first subset of battery storage elements at a different state of charge than a second subset of battery storage elements based on the determined states of charge.
4 . The energy storage system of claim 3 , wherein the running the battery storage elements of the energy storage node at the one or more selected operating conditions includes dispatching a required power flow across the first subset of battery storage elements and the second subset of battery storage elements of the energy storage node at the one or more selected operating conditions during a normal operation to reduce a mismatch in the states of charge between the first subset of battery storage elements and the second subset of battery storage elements.
5 . The energy storage system of claim 4 , wherein the one or more selected operating conditions include an operational bias during the normal operation.
6 . The energy storage system of claim 3 , wherein the running the battery storage elements of the energy storage node at the one or more selected operating conditions includes charging or discharging the first subset of battery storage elements and the second subset of battery storage elements of the energy storage node at the one or more selected operating conditions during a maintenance operation to reduce a mismatch in the states of charge between the first subset of battery storage elements and the second subset of battery storage elements.
7 . The energy storage system of claim 1 , wherein the plurality of operating conditions include a temperature, an electrical resistance, a current rate (C-rate), a current carrying capability, an eddy current, a conductance, a power pulse pattern during charging or discharging, other electrical characteristics, or a power command from the PCS.
8 . The energy storage system of claim 1 , wherein the running the battery storage elements of the energy storage node at the one or more selected operating conditions of the plurality of operating conditions based on the battery charge and discharge characteristics to reduce the imbalance in state of charge among the battery storage elements of the energy storage node includes:
selecting the one or more selected operating conditions of the plurality of operating conditions based on the battery charge and discharge characteristics to reduce the imbalance in the state of charge among the battery storage elements of the energy storage node; and
running the battery storage elements of the energy storage node at the one or more selected operating conditions.
9 . The energy storage system of claim 8 , wherein the selecting the one or more selected operating conditions of the plurality of operating conditions based on the battery charge and discharge characteristics to reduce the imbalance in the state of charge among the battery storage elements of the energy storage node includes:
applying one or more balancing models to the battery charge and discharge characteristics and the determined states of charge over one or more time periods; and
selecting the one or more selected operating conditions based on the applied one or more balancing models.
10 . The energy storage system of claim 9 , wherein the applying one or more balancing models to the battery charge and discharge characteristics and the determined states of charge over one or more time periods includes:
feeding the states of charge into one or more balancing models;
holding the states of charge over one or more time periods; and
matching the states of charge over the more time periods against operating condition patterns previously identified as being associated with reducing the imbalance in the determined states of charge.
11 . A non-transitory computer-readable medium, comprising node balancing programming, wherein execution of the node balancing programming by one or more processors configures one or more controllers to:
receive or store battery charge and discharge characteristics of a plurality of battery storage elements of an energy storage node during a plurality of operating conditions of the battery storage elements, a power conversion system (PCS), or both; and
run the battery storage elements of the energy storage node at one or more selected operating conditions of the plurality of operating conditions based on the battery charge and discharge characteristics to reduce an imbalance in state of charge among the battery storage elements of the energy storage node.
12 . The non-transitory computer-readable medium of claim 11 , wherein execution of the node balancing programming by one or more processors configures one or more controllers to:
determine states of charge of each of the battery storage elements of the energy storage node from battery data during the one or more selected operating conditions.
13 . The non-transitory computer-readable medium of claim 12 , wherein execution of the node balancing programming by one or more processors configures one or more controllers to:
identify a first subset of battery storage elements at a different state of charge than a second subset of battery storage elements based on the determined states of charge.
14 . The non-transitory computer-readable medium of claim 13 , wherein the running the battery storage elements of the energy storage node at the one or more selected operating conditions includes dispatching a required power flow across the first subset of battery storage elements and the second subset of battery storage elements of the energy storage node at the one or more selected operating conditions during a normal operation to reduce a mismatch in the states of charge between the first subset of battery storage elements and the second subset of battery storage elements.
15 . The non-transitory computer-readable medium of claim 14 , wherein the one or more selected operating conditions include an operational bias during the normal operation.
16 . A method, comprising:
receiving or storing battery charge and discharge characteristics of a plurality of battery storage elements of an energy storage node during a plurality of operating conditions of the battery storage elements, a power conversion system (PCS), or both; and
running the battery storage elements of the energy storage node at one or more selected operating conditions of the plurality of operating conditions based on the battery charge and discharge characteristics to reduce an imbalance in state of charge among the battery storage elements of the energy storage node.
17 . The method of claim 16 , further comprising:
determining states of charge of each of the battery storage elements of the energy storage node from battery data during the one or more selected operating conditions.
18 . The method of claim 17 , further comprising:
identifying a first subset of battery storage elements at a different state of charge than a second subset of battery storage elements based on the determined states of charge.
19 . The method of claim 18 , wherein the running the battery storage elements of the energy storage node at the one or more selected operating conditions includes dispatching a required power flow across the first subset of battery storage elements and the second subset of battery storage elements of the energy storage node at the one or more selected operating conditions during a normal operation to reduce a mismatch in the states of charge between the first subset of battery storage elements and the second subset of battery storage elements.
20 . The method of claim 19 , wherein the one or more selected operating conditions include an operational bias during the normal operation.