Smart electrical bushing with integrated sensor
Electrical bushing for medium and high voltage, the bushing including a fluid filled insulation volume; a sensor unit in contact with the fluid in the fluid filled insulation volume; wherein the sensor unit is configured to measure a breakdown voltage of the fluid.
1 . Electrical bushing for medium and high voltage, the bushing comprising:
a fluid filled insulation volume; and
a sensor unit in contact with the fluid in the fluid filled insulation volume, the sensor unit configured to measure a breakdown voltage of the fluid,
wherein the sensor unit is mounted in a radial protrusion that extends from a body of the electrical bushing and is in contact with the fluid, wherein the radial protrusion is formed by and extends from the body of the electrical bushing, the radial protrusion defining a portion of the fluid filled insulation volume of the electrical bushing.
2 . The electrical bushing according to claim 1 , wherein the bushing has a top portion and a bottom portion, wherein the bottom portion is adapted for being connected to a transformer.
3 . The electrical bushing according to claim 1 , wherein the radial protrusion is sealed relative to the bushing body and forms a pressure-tight extension of the fluid filled insulation volume.
4 . The electrical bushing according to claim 2 , wherein the radial protrusion is located in the bottom portion of the electrical bushing.
5 . The electrical bushing according to claim 1 , wherein the sensor unit is wirelessly connected to a controller for transmitting the measured breakdown voltage to the controller.
6 . The electrical bushing according to claim 5 , wherein the controller is connected to network through a network interface for connecting the controller to a data network, wherein the controller is operatively connected to the network interface for at least one of carrying out a command received from the data network and sending status information of the electrical bushing to the data network;
wherein the controller optionally comprises a processing unit for converting a measured breakdown voltage into a digital signal.
7 . The electrical bushing according to claim 1 , wherein the sensor unit is further configured to measure at least one of a pressure, a temperature, a moisture level of moisture content in the fluid and a density of the fluid in the electrical bushing.
8 . The electrical bushing according to claim 2 , wherein the bottom portion is adapted for being inserted into an opening of a transformer housing.
9 . The electrical bushing according to claim 2 , wherein the sensor unit is installed in the bottom portion of the electrical bushing to be inserted into an opening of a transformer housing.
10 . A transformer assembly for medium and high voltage, the assembly comprising:
a transformer having a transformer housing; and
an electrical bushing comprising:
a fluid filled insulation volume; and
a sensor unit in contact with the fluid in the fluid filled insulation volume, the sensor unit configured to measure a breakdown voltage of the fluid,
wherein the sensor unit is mounted in a radial protrusion that extends from a body of the electrical bushing and is in contact with the fluid, wherein the radial protrusion is formed by and extends from the body of the electrical bushing, the radial protrusion defining a portion of the fluid filled insulation volume of the electrical bushing.
11 . The transformer assembly according to claim 10 , wherein the sensor unit is located on a portion of the bushing that is located within an opening of the transformer housing.
12 . The transformer assembly of according to claim 10 , wherein the bushing comprises a shielding structure for shielding a sensor of the sensor unit from electromagnetic influences of the transformer.
13 . The transformer assembly of according to claim 10 , wherein the bushing comprises a seal that keeps a transformer fluid in the transformer from contacting the sensor of the sensor unit.
14 . The transformer assembly according to claim 10 , wherein the bushing has a top portion and a bottom portion, wherein the bottom portion is inserted into an opening of the transformer housing.
15 . The transformer assembly according to claim 14 , wherein the radial protrusion is located in the bottom portion of the electrical bushing.
16 . The transformer assembly according to claim 10 , wherein the radial protrusion is located on a side of the bushing.
17 . The transformer assembly according to claim 10 , wherein the sensor unit is wirelessly connected to a controller for transmitting the measured breakdown voltage to the controller.
18 . A method for detecting a breakdown flag indicative of a failing medium or high voltage bushing having a fluid filled insulation volume, the method comprising
acquiring sensor data by a sensor unit of the bushing, the sensor unit being in contact with a fluid in the fluid filled insulation volume, the sensor data describing a breakdown voltage of the fluid, wherein the sensor unit is mounted in a radial protrusion that extends from a body of the electrical bushing and is in contact with the fluid, wherein the radial protrusion is formed by and extends from the body of the electrical bushing, the radial protrusion defining a portion of the fluid filled insulation volume of the electrical bushing;
determining a breakdown flag, the breakdown flag describing whether the sensor data has passed a threshold for the breakdown voltage of the fluid in the bushing; and
issuing a control signal based on the breakdown flag.
19 . The method according to claim 18 , the method comprising
acquiring transformer data, the transformer data describing a state of the transformer,
determining a service flag, the service flag describing whether the transformer has passed a servicing threshold based on the state of the transformer data and the breakdown flag.
20 . The method according to claim 18 , wherein the method comprises servicing the bushing based on the control signal and/or the service flag.