Systems and methods for integrating distributed energy resources
The present invention is an apparatus and method for using aggregated loads from a plurality of distributed energy resources to perform a function at a power distribution feeder. The invention includes a plurality of distributed energy resources, wherein at least one distributed energy resource includes a renewable energy resource, a communication network, a control device, a power distribution feeder coupled to the control device, and an energy storage system coupled to the power distribution feeder. The control device sends a signal to the plurality of distributed energy resources via the communication network. The signal is a request to switch a status of one or more of the distributed energy resources if one or more distributed energy resources is within a predetermined condition. Loads from the one or more of the distributed energy resources that switched status are aggregated to perform a function at the power distribution feeder.
1. A smart control unit for a thermostatically controlled load, comprising:
a smart control unit adapted to switch status of the thermostatically controlled load;
wherein the smart control unit is adapted to receive a probability signal via a communication network, and wherein:
the probability signal is calculated at a power distribution feeder for a plurality of thermostatically controlled loads that draw electrical power from said power distribution feeder, wherein the probability signal includes a status switch probability to be applied independently by multiple of the plurality of thermostatically controlled loads so that each of the multiple thermostatically controlled loads has a probability of switching status which is controlled by the probability signal, and so that the aggregated multiple thermostatically controlled loads thereby present an aggregate load at the power distribution feeder which is controlled by the probability signal; and
wherein the smart control unit is adapted to apply said probability signal in connection with control of the thermostatically controlled load, by applying a function having the status switch probability of switching status of the thermostatically controlled load.
2. A smart control unit according to claim 1 , wherein the function generates a random number from a uniform distribution density function and compares the random number to the status switch probability included in the probability signal.
3. A smart control unit according to claim 1 , wherein the thermostatically controlled loads includes a thermal storage unit.
4. A smart control unit according to claim 1 , wherein the smart control unit comprises a smart thermostat, and wherein switching status of the thermostatically controlled load comprises activating or deactivating a heating or cooling system.
5. A smart control unit according to claim 1 , wherein the smart control unit is adapted to receive the probability signal via the communication network about once per second.
6. A smart control unit according to claim 1 , wherein the smart control unit is adapted to apply the status switch probability of the probability signal when a predetermined condition is met, and wherein the predetermined condition is a temperature at the thermostatically controlled load which is measured to be within a predetermined temperature range.
7. A smart control unit according to claim 1 , wherein the smart control unit is furthermore adapted to apply a switching dead-time after switching status of the thermostatically controlled load.
8. A method to control a thermostatically controlled load, comprising:
receiving, at a smart control unit adapted to switch status of the thermostatically controlled load, a probability signal via a communication network, wherein:
the probability signal is calculated at a power distribution feeder for a plurality of thermostatically controlled loads that draw electrical power from said power distribution feeder, wherein the probability signal includes a status switch probability to be applied independently by multiple of the plurality of thermostatically controlled loads so that each of the multiple thermostatically controlled loads has a probability of switching status which is controlled by the probability signal, and so that the aggregated multiple thermostatically controlled loads thereby present an aggregate load at the power distribution feeder which is controlled by the probability signal; and
applying, by the smart control unit, said probability signal in connection with control of the thermostatically controlled load, by applying a function having the status switch probability of switching status of the thermostatically controlled load.
9. A method according to claim 8 , wherein the function generates a random number from a uniform distribution density function and compares the random number to the status switch probability included in the probability signal.
10. A method according to claim 8 , wherein the thermostatically controlled loads includes a thermal storage unit.
11. A method according to claim 8 , wherein the smart control unit comprises a smart thermostat, and wherein switching status of the thermostatically controlled load comprises activating or deactivating a heating or cooling system.
12. A method according to claim 8 , wherein the smart control unit receives the probability signal via the communication network about once per second.
13. A method according to claim 8 , further comprising applying, by the smart control unit, the status switch probability of the probability signal when a predetermined condition is met, wherein the predetermined condition is a temperature at the thermostatically controlled load which is measured to be within a predetermined temperature range.
14. A method according to claim 8 , further comprising applying, by the smart control unit, a switching dead-time after switching status of the thermostatically controlled load.
15. A method to control an aggregate load at a power distribution feeder, comprising:
calculating a probability signal for a plurality of thermostatically controlled loads that draw electrical power from said power distribution feeder, wherein the probability signal includes a status switch probability to be applied independently by multiple of the plurality of thermostatically controlled loads so that each of the multiple thermostatically controlled loads has a probability of switching status which is controlled by the probability signal, and so that the aggregated multiple thermostatically controlled loads thereby present an aggregate load at the power distribution feeder which is controlled by the probability signal; and
sending the probability signal to the plurality of thermostatically controlled loads via a communication network.
16. A method according to claim 15 , further comprising adjusting the probability signal to accommodate intermittent renewable energy generation.
17. A method according to claim 15 , further comprising adjusting the probability signal in order to reduce peak load at the power distribution feeder.
18. A method according to claim 15 , further comprising adjusting the probability signal in order to shift power distribution feeder loads to off-peak periods.
19. A method according to claim 15 , further comprising adjusting the probability signal in order to control a ramp rate of power at the power distribution feeder.
20. A method according to claim 15 , wherein the plurality of thermostatically controlled loads include thermal storage units or smart thermostats.