System and method for detecting distribution transformer overload
View Patent ↗A system, device, and method of detecting an overload condition of a distribution transformer that supplies power to one or more customer premises via a low voltage subnet is provided. In one embodiment, the method comprises determining the power output of the transformer; storing in a memory a threshold power value for the transformer; determining whether the power output exceeds the threshold power value; and, if the output power exceeds the threshold power value, providing a notification. Providing the notification may include wirelessly transmitting the notification and/or transmitting the notification over a medium voltage power line. The low voltage subnet may comprise a low voltage feeder that supplies power to a plurality of low voltage supply lines that extend to the customer premises in which case determining the output power may comprise measuring a voltage of the low voltage feeder and measuring a current traversing the low voltage feeder. The method may also comprise storing in the memory a plurality of threshold power values associated with a plurality of transformers, such as different models of transformers; receiving data of the power output of a multitude of transformers; and determining whether the power output of each of the multitude of transformers exceeds the threshold value associated with the transformer, which steps may be performed at a central computer system such as a power line server.
1. A method, implemented at least in part by a computer system, of detecting an overload condition of a distribution transformer supplying power to one or more customer premises via a low voltage subnet, comprising:
determining the power output of the distribution transformer;
storing in a memory a threshold power value for the distribution transformer;
determining whether the power output exceeds the threshold power value for a predetermined time period; and
if the output power exceeds the threshold power value for the predetermined time period, providing a notification.
2. The method of claim 1 , wherein said determining whether the output power exceeds the threshold power value comprises determining whether the output power exceeds a rating by a predetermined value for the predetermined time period.
3. The method of claim 1 , wherein the low voltage subnet comprises a low voltage feeder that supplies power to a plurality of low voltage supply lines and said determining the output power comprises:
measuring a voltage of the low voltage feeder; and
measuring a current traversing the low voltage feeder.
4. The method of claim 1 , wherein said determining the power output of the transformer comprises determining the power entering all of the one or more customer premises.
5. The method of claim 1 , wherein said determining the output power of the transformer comprises measuring the power supplied to the transformer.
6. The method of claim 5 , wherein said determining the output power further comprises computing the output power based on a turns ratio of the transformer.
7. The method of claim 6 , wherein said determining the output power further comprises computing the output power based on an efficiency of the transformer.
8. The method of claim 1 , wherein said providing a notification comprises transmitting the notification over a medium voltage power line.
9. The method of claim 1 , wherein said providing a notification comprises wirelessly transmitting the notification.
10. The method of claim 1 , wherein said providing a notification comprises transmitting information sufficient for determining a location of the transformer.
11. The method of claim 1 , wherein said determining the power output of the transformer comprises receiving power data from a meter associated with each of the one or more customer premises supplied power by the transformer.
12. The method of claim 11 , wherein said determining the power output of the transformer further comprises summing the received power data.
13. The method of claim 1 , further comprising transmitting data of the determined power output to a remote device.
14. The method of claim 13 , wherein said determining whether the power output exceeds the threshold power value is performed at the remote device.
15. The method of claim 13 , wherein the transformer comprises an underground residential distribution transformer.
16. The method of claim 13 , wherein the transformer is connected to a medium voltage power line via a tap conductor and said determining the power output comprises measuring the power traversing the medium voltage power line.
17. The method of claim 13 , wherein said determining the power output comprises measuring a current traversing a power line via a sensor device that includes a Rogowski coil.
18. The method of claim 1 , further comprising:
storing in the memory a plurality of threshold power values associated with a plurality of transformers;
receiving data of the power output of a multitude of transformers; and
determining whether the power output of each of the multitude of transformers exceeds the threshold value associated with the transformer.
19. A method of detecting an overload condition of a distribution transformer supplying power to one or more customer premises via a low voltage subnet, comprising:
measuring a voltage of the low voltage subnet over a time period;
measuring a current of the low voltage subnet over the time period;
computing a power output based on said measured voltage and said measured current;
storing in a memory a threshold power value for the distribution transformer;
determining whether the power output exceeds the threshold power value for a predetermined time period; and
if the output power exceeds the threshold power value for the predetermined time period, transmitting a notification.
20. The method of claim 19 , wherein the threshold power value comprises a percentage over a rating for the transformer.
21. The method of claim 19 , wherein said transmitting the notification comprises transmitting the notification over a medium voltage power line.
22. The method of claim 19 , wherein said transmitting the notification comprises wirelessly transmitting the notification.
23. The method of claim 19 , wherein said transmitting the notification comprises transmitting the notification via a fiber optic communication.
24. The method of claim 19 , further comprising transmitting data of the computed power output to a remote device.
25. The method of claim 24 , wherein said comparing the power output with the threshold power value is performed at the remote device.
26. The method of claim 24 , wherein the transformer comprises an underground residential distribution transformer.
27. The method of claim 24 , wherein said measuring a current comprises measuring a current traversing a power line via a sensor device that includes a Rogowski coil.
28. The method of claim 19 , wherein
said determining the power output comprises averaging the measured voltage and the measured current over the time period.
29. A method, implemented at least in part by a computer system, of detecting an overload condition of a distribution transformer supplying power to a plurality of customer premises via a low voltage subnet, wherein each of the plurality of customer premises includes an associated power meter, comprising:
a. receiving power data that comprises the power measured by the power meter associated with each of the plurality of customer premises;
b. combining the received power data to determine a combined power;
c. determining the power output of the transformer based on the combined power;
d. storing in a memory a threshold power value for the transformer;
e. determining whether the power output exceeds the threshold power value; and
f. if the output power exceeds the threshold power value, providing a notification.
30. The method of claim 29 , wherein said determining the power output of the transformer based on the combined power comprises averaging the combined power over time.
31. The method of claim 29 , wherein said determining the power output of the transformer based on the combined power comprises adding a low voltage power line loss value to the combined power.
32. The method of claim 29 , further comprising performing steps a-f with the computer system for a plurality of transformers.
33. The method of claim 29 wherein said providing a notification comprises transmitting the notification over a medium voltage power line.
34. The method of claim 29 wherein said providing a notification comprises wirelessly transmitting the notification.
35. The method of claim 29 , wherein said providing a notification comprises transmitting information of the sufficient for determining a location of the transformer.