Control systems and methods for economical optimization of an electrical system including battery degradation
The present disclosure is directed to systems and methods for economically optimal control of an electrical system. Some embodiments employ generalized multivariable constrained continuous optimization techniques to determine an optimal control sequence over a future time domain in the presence of any number of costs, savings opportunities (value streams), and constraints. Some embodiments also include control methods that enable infrequent recalculation of the optimal setpoints. Some embodiments may include a battery degradation model that, working in conjunction with the economic optimizer, enables the most economical use of any type of battery. Some embodiments include techniques for load and generation learning and prediction. Some embodiments include consideration of external data, such as weather.
1. A controller of an electrical system that includes a battery, the controller comprising:
a communication interface to receive a current state of a battery of an electrical system; and
one or more processors to:
receive a set of configuration elements specifying a manner of calculating each of one or more cost elements associated with operation of the electrical system;
receive a set of process variables that include one or more measurements of a state of the electrical system, including the current state of charge of the battery;
determine battery degradation of the battery predicted to arise from operation of the electrical system for a future time period, based on the current state of the battery;
determine a battery degradation cost predicted to arise from the operation of the electrical system based on the determined battery degradation for the future time period; and
control the electrical system via the communication interface to optimize operation of the electrical system, based on one or more cost elements associated with operation of the electrical system, the one or more cost elements including an electricity cost and the determined battery degradation cost, wherein controlling the electrical system comprises determining values for a set of control variables to communicate to the electrical system to effectuate a change to the electrical system toward meeting a controller objective for economical optimization of the electrical system, in accordance with the configuration elements.
2. The controller of claim 1 , wherein the one or more processors control the electrical system during an upcoming time domain that includes the future time period.
3. The controller of claim 1 , wherein the current state of the battery comprises a state of charge of the battery.
4. The controller of claim 1 , wherein the one or more processors determine the battery degradation by:
determining a throughput component of the battery degradation for the future time period; and
determining an aging component of battery degradation for the future time period.
5. The controller of claim 4 , wherein the one or more processors determine the throughput component based on a rate of battery capacity loss versus a change in a state of charge of the battery.
6. The controller of claim 4 , wherein the one or more processors determine the aging component based on a rate of battery capacity loss versus time.
7. The controller of claim 1 , wherein the one or more processors determine the battery degradation as an integral of an integrand that comprises one or both of a throughput term and an aging term, wherein the throughput term includes a partial differential of a battery condition with respect to a state of charge and the aging term includes a partial differential of a battery condition with respect to time.
8. The controller of claim 7 , wherein the throughput term comprises a function of the rate of charge or discharge of the battery, the state of charge of the battery, and the temperature of the battery.
9. The controller of claim 7 , wherein the throughput term represents a rate of battery capacity loss versus a change in the state of charge of the battery.
10. The controller of claim 7 , wherein the aging term comprises a function of the battery state including the state of charge of the battery and a temperature of the battery.
11. The controller claim 7 , wherein the aging term represents a rate of battery capacity loss versus time.
12. The controller of claim 1 , wherein the one or more processors control the electrical system by determining a set of control values for a set of control variables to effectuate a change to the electrical system toward meeting a controller objective for economical optimization of the electrical system, wherein the set of control values are determined by the one or more processors in accordance with the one or more cost elements associated with operation of the electrical system.
13. The controller of claim 12 , wherein the one or more processors control the electrical system during an upcoming time domain including the future time period.
14. The controller of claim 12 , wherein the one or more processors determine the set of control values utilizing of an optimization algorithm.
15. The controller of claim 1 , wherein determining the battery degradation cost comprises multiplying the battery degradation of the battery for the future time period by a cost factor.
16. The controller of claim 15 , wherein the cost factor is based on a total cost of the battery.
17. The controller of claim 15 , wherein the cost factor is determined as a total cost of the battery divided by the amount of battery degradation resulting in end of life of the battery.
18. A method of a controller of an electrical system including a battery, the method comprising:
receiving from a sensor of an electrical system a current state of a battery of an electrical system;
receiving a set of configuration elements specifying a manner of calculating each of one or more cost elements associated with operation of the electrical system, the one or more cost elements including an electricity cost and a battery degradation cost;
receiving a set of process variables that include one or more measurements of a state of the electrical system, including the current state of charge of the battery;
determining a battery degradation of the battery predicted to arise from operation of the electrical system for a future time period of an upcoming time domain, based on the current state of the battery;
determining a battery degradation cost predicted to arise from the operation of the electrical system based on the determined battery degradation of the battery for the future time period; and
controlling the electrical system to optimize operation of the electrical system during the upcoming time domain, based on the determined battery degradation cost, wherein controlling the electrical system comprises determining values for a set of control variables to communicate to the electrical system to effectuate a change to the electrical system toward meeting a controller objective for economical optimization of the electrical system, in accordance with the configuration elements.
19. The method of claim 18 , wherein the set of configuration elements specify one or more constraints of the electrical system, and
wherein the determining values for the set of control variables includes utilization of a continuous optimization algorithm to find the set of values for the set of control variables according to the one or more cost elements and the one or more constraints.
20. The method of claim 18 , wherein controlling the electrical system comprises:
determining the values for the set of control variables for configuring the electrical system, wherein the values are determined based on the battery degradation cost; and
utilizing the values for the set of control variables to control the electrical system.
21. The method of claim 18 , wherein determining the battery degradation comprises:
determining a throughput component of degradation of the battery for the future time period;
determining an aging component of degradation of the battery for the future time period; and
summing the throughput component and the aging component to determine the battery degradation for the future time period.
22. The method of claim 21 , wherein determining the throughput component is based on a rate of battery capacity loss versus a change in the state of charge of the battery.
23. The method of claim 21 , wherein the throughput component comprises a function of the rate of charge or discharge of the battery, the state of charge of the battery, and the temperature of the battery.
24. The method of claim 21 , wherein determining the aging component is based on a rate of battery capacity loss versus time.
25. The method of claim 21 , wherein the aging component comprises a function of the battery state including the state of charge of the battery and a temperature of the battery.
26. The method of claim 18 , wherein determining the battery degradation cost comprises multiplying the battery degradation for the future time period by a cost factor.
27. The method of claim 18 , wherein the battery degradation is determined as an integral of an integrand that comprises one or both of a throughput term and an aging term, wherein the throughput term includes a partial differential of a battery condition with respect to a state of charge and the aging term includes a partial differential of a battery condition with respect to time.
28. The controller of claim 27 , wherein the throughput term comprises a function of the rate of charge or discharge of the battery, the state of charge of the battery, and the temperature of the battery.
29. The controller of claim 27 , wherein the throughput term represents a rate of battery capacity loss versus a change in the state of charge of the battery.
30. The controller of claim 27 , wherein the aging term comprises a function of the battery state including the state of charge of the battery and a temperature of the battery.
31. The controller of claim 27 , wherein the aging term represents a rate of battery capacity loss versus time.