Photovoltaic management and module-level power electronics
A photovoltaic (PV) system includes module-level power electronic (MLPE) devices that produce energy. The PV system includes a gateway to receive and send data to MLPE devices. The gateway also connects the PV system with a network, such as a local area network, that allows access to the Internet. The gateway provides functionality within the PV system to perform various processes to improve operation of MLPE devices.
1. A method of managing a photovoltaic system with photovoltaic module-level power electronics (MLPE), the method comprising:
one of installing or updating a digital encryption standard (DES) key used by a gateway to one of enable or disable power production at one or more MLPE devices;
generating a message including the DES key and transmitting the message from the gateway to the one or more MLPE devices;
receiving a response to the message at the gateway from the one or more MLPE devices; and
one of enabling or disabling power production at the one or more MLPE devices based on the response to the message.
2. The method of claim 1 , further comprising encrypting the message using a one-time pad cipher received at the gateway from a utility vendor.
3. The method of claim 2 , further comprising packaging the one-time pad cipher into a power line communication (PLC) message.
4. The method of claim 2 , wherein the one-time pad cipher comprises 32 56-bit DES keys, a 32-bit one-time pad cipher identifier, and a 32-bit previous one-time pad cipher identifier.
5. The method of claim 4 , wherein each of the 32-bit one-time pad cipher identifier and the 32-bit previous one-time pad cipher identifier are two random 32-bit numbers R1 and R2, respectively, and wherein R1 now >R1 previous and R2 now <R2 previous.
6. The method of claim 4 , further comprising decrypting the message at the one or more MLPE devices using 3-DES keys.
7. The method of claim 1 , further comprising determining whether a poll cycle for the message is a last poll cycle, wherein the poll cycle comprises generating the message including the DES key and receiving the response to the message.
8. The method of claim 7 , wherein the DES key is valid for one hundred and twenty-eight (128) poll cycles, and further comprising updating the DES key to a new DES key after the 128 poll cycles.
9. The method of claim 1 , wherein the one of the enabling or disabling power production at the one or more MLPE devices is based on the message including a determination that the DES key is correct or incorrect, respectively.
10. The method of claim 9 , wherein prior to disabling power production at the one or more MLPE devices if the DES key is incorrect, sending an alert to the gateway from the one or more MLPE devices, determining whether the alert is cleared by the one or more MLPE devices, and if the alert is cleared by the one or more MLPE devices, generating a new message including the DES key and transmitting the new message from the gateway to the one or more MLPE devices.
11. A photovoltaic (PV) system with photovoltaic module-level power electronics (MLPE), comprising:
one or more MLPE devices; and
a gateway communicatively connected to the one or more MLPE devices and programmed to one of install or update a digital encryption standard (DES) key to one of enable or disable power production at one or more MLPE devices, generate a message including the DES key and transmit the message to the one or more MLPE devices, receive a response to the message from the one or more MLPE devices, and one of enable or disable power production at the one or more MLPE devices based on the response to the message.
12. The PV system of claim 11 , wherein the gateway is communicatively connected to a utility vendor and programmed to encrypt the message using a one-time pad cipher received from the utility vendor.
13. The PV system of claim 12 , wherein the gateway is further programmed to package the one-time pad cipher into a power line communication (PLC) message.
14. The PV system of claim 12 , wherein the one-time pad cipher comprises 32 56-bit DES keys, a 32-bit one-time pad cipher identifier, and a 32-bit previous one-time pad cipher identifier.
15. The PV system of claim 14 , wherein each of the 32-bit one-time pad cipher identifier and the 32-bit previous one-time pad cipher identifier are two random 32-bit numbers R1 and R2, respectively, and wherein R1 now >R1 previous and R2 now <R2 previous.
16. The PV system of claim 14 , wherein the one or more MLPE devices are programmed to decrypt the message using 3-DES keys.
17. The PV system of claim 11 , wherein the gateway is further programmed to determine whether a poll cycle for the message is a last poll cycle, and wherein the poll cycle comprises generating the message including the DES keys and receiving the response to the message.
18. The PV system of claim 17 , wherein the DES key is valid for one hundred and twenty-eight (128) poll cycles, and wherein the gateway is further programmed to update the DES key to a new DES key after the 128 poll cycles.
19. The PV system of claim 11 , wherein the gateway is further programmed to one of enable or disable power production at the one or more MLPE devices based on the message including a determination that the DES key is correct or incorrect, respectively.
20. The PV system of claim 19 , wherein prior to the gateway disabling power production at the one or more MLPE devices if the DES key is incorrect, the gateway is further programmed to receive an alert from the one or more MLPE devices, determine whether the alert is cleared by the one or more MLPE devices, and if the alert is cleared by the one or more MLPE devices, generate a new message including the DES key and transmitting the new message to the one or more MLPE devices.