Alternative power source for network protector relay

Abstract

A relay for control of a network protector located on a low voltage side of a transformer with a set of three phases, the relay having at least one route for power to be provided to the relay from at least one of the set of three phases taken from a transformer side of the network protector so that the relay may have power and be functional before the network protector is closed to provide power into a dead network.

Claims

1. A relay for control of a network protector located on a low voltage side of a transformer with a set of three phases: the relay having a set of at least one input port to receive power from at least one of the set of three phases on a network side of the network protectors, wherein power provided from the network side of the network protector is available for operation of the relay; and the relay providing power to a communication device that communicates information about the transformer and the network protector to a remote location; wherein the improvement comprises: at least one route for power to be provided to the relay from at least one of the set of three phases taken from a power source side of the network protector so that the relay has power and is functional before the network protector is closed to provide power into a dead network; the at least one route for power including a voltage reduction unit to reduce a voltage of power received from the power source side of the network protector; wherein the voltage reduction unit is turned off by a network voltage detector upon detecting that at least one phase on the network side of the network protector is energized; and the communication device transmits information from the relay connected to the dead network before any network protector is closed.

2. The relay of claim 1 wherein power cannot flow from the at least one of the set of three phases taken from the power source side of the network protector to the at least one of the set of three phases on the network side of the network protector to bypass the network protector.

3. The relay of claim 1 wherein the communication device receives information from the remote location so that a command generated at the remote location, transmitted to the communication device, passed to the relay, is executed before any network protector is closed to allow power to energize the dead network.

4. The relay of claim 1 wherein the relay and the communication device are within one housing and the communication device uses power line carrier.

5. The relay of claim 1 wherein the relay and the communication device are within one housing and the communication device uses optical fiber.

6. The relay of claim 1 wherein the relay and the communication device are within one housing and the communication device uses telephone line.

7. The relay of claim 1 wherein the relay and the communication device are within one housing and the communication device uses wireless radio.

8. A process to de-energize and re-energize a local network, the local network fed by a set of at least one transformer connected to the local network through a network protector; the network protector selectively operating: in a closed state to pass power from the transformer to the local network; or in an open state when the transformer is isolated from the local network, the network protector receiving inputs from a relay that changes the network protector from the closed state to the open state; the network protector receiving inputs from the relay that changes the network protector from the open state to the closed state; the relay providing power to a communication device that communicates information received from the relay to a remote location; the relay having access to at least one source of power on a local network side of the network protector and to at least one source of power on a power source side of the network protector; the process comprising: stop providing power to the local network by stopping power to a last transformer providing power to the local network; as the local network ceases to have power, all relays for network protectors connected to the local network send a signal to the network protector to go from the closed state to the open state; provide power to a primary side of a first transformer feeding the local network, wherein the first transformer is not required to be the last transformer providing power to the local network before stopping provision of power to the local network; energize a first relay with power obtained between a secondary side of the first transformer and a first network protector connected to the first transformer, the first network protector in an open state; the power used to energize the first relay passing through a voltage reduction unit to reduce a voltage of power received from between the secondary side of the first transformer and the first network protector; close the first network protector after receipt of input to the first network protector from the first relay; turn off the voltage reduction unit after a network voltage detector detects that at least one phase on the local network side of the first network protector is energized; and energize any other relays connected to the local network with power from the local network.

9. The process of claim 8 wherein the input to the first network protector from the first relay is delayed while the first relay assesses appropriateness of closing the first network protector based upon a set of data from local instruments.

10. The process of claim 8 wherein the input to the first network protector from the first relay to close the first network protector conveys a command from the remote location received by a first communication device and provided to the first relay wherein the first communication device is provided power by the first relay and becomes energized before the local network is energized.

Description

BRIEF DESCRIPTION OF THE FIGURES

(1) The disclosure can be better understood with reference to the following figures. The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the disclosure. Moreover, in the figures, like reference numerals designate corresponding parts throughout the different views.

(2) FIG. 1 introduces the relevant components in a prior art electrical distribution network and the devices used to convey information about components to a remote monitoring station.

(3) FIG. 2 shows a portion of a prior art network including the relay that controls a network protector.

(4) FIG. 3 is a flow chart showing the prior art process of de-energizing and re-energizing a local network.

(5) FIG. 4 shows a portion of a network including an additional source of power for the relays that control the network protectors.

(6) FIG. 5 is a flow chart showing a process of de-energizing and re-energizing a local network where the relay is energized while the associated network protector is still open.

(7) FIG. 6 shows a transformer side power source for use by the relay.

(8) FIG. 7 shows a power connection to the transformer side of the network protector including a voltage reduction unit.

(9) FIG. 8 shows a power connection on the transformer side of then network protector with a network voltage detector that turns off the voltage reduction unit when power is available from the network side of the network protector.

DETAILED DESCRIPTION

(10) FIG. 4 shows the drawing from FIG. 2 but with an additional connection 312 for the relay 168 to obtain power from at least one phase on the secondary side 158 of the transformer 150 and before the network protector 166. The particular phase used to provide power via connection 312 is not central to this disclosure as any of the three phases may be used.

(11) In order to show the added connection 312, the diagram has been expanded in that section. One of skill in the art will appreciate that these diagrams used to illustrate relevant connections are not representative of the length of the connectors between components.

(12) The impact of this change means that the process of reviving a dead network now allows the relay 168 downstream of the one transformer 150 that is energized, to boot and make a decision on whether to close the network protector 166. The energized relay 168 and energized transmitter 216 may convey information to a remote location on various parameters known to the relay 168. The energized transmitter 216 may receive commands from a remote location and provide the commands to the energized relay 168. Thus, the network protector 166 may be closed by the relay 168 into a dead network by remote command.

(13) Revised Process to De-Energize and Re-Energize.

(14) Thus, the process of de-energizing and re-energizing a local network 116 may be implemented as shown in the flowchart in FIG. 5.

(15) Step 2104Stop flow of power to primary side 154 of last transformer 150 providing power to a local network 116. This may be done by opening the relevant transformer breaker 162 (FIG. 1).

(16) Step 2108As the relays 168 associated with each of the transformers 150 associated with a local network 116 lose power, send commands to open any closed network protectors 166 associated with the local network 116.

(17) Step 2112Provide power to the primary side 154 of at least one transformer 150 associated with the local network 116.

(18) Step 2116Power passes from the secondary side 158 of the at least one transformer 150 associated with the local network 116 to provide power to the relay 168 associated with network protector 166 for that transformer 150 while the network protector 166 remains open.

(19) Step 2120After the relay 168 associated with the energized transformer 150 becomes operational; an assessment is made on the appropriateness of closing the network protector 166 to energize the local network 116.

(20) Step 2124If appropriate, the network protector 166 is closed by the relay 168 to thus provide power from the energized transformer 150 to the local network 116.

(21) Step 2128Other relays 168 associated with network protectors 166 for other transformers 150 not yet energized, obtain power from the local network side 118 of the network protectors 166 and boot to become operational.

(22) Notice, that the relay 168 may communicate the reason for not closing the network protector 166 via the transmitter 216 which can communicate through the energized transformer 150. Alternatively, the relay 168 may communicate the reason for not closing the network protector 166 through some other communication path including fiber optic communication, and various wired and wireless communication options including telephone lines and wireless radio.

(23) Thus, a relay 168 may be operated to send an open command (also known as trip) to the associated network protector 166 whenever the relay 168 loses power. This allows the relay 168 to boot and make an informed decision before closing a network protector 166 once power is provided to the relevant transformer 150.

(24) Examples of Assessments Made Before Closing the Network Protector

(25) Respecting a BLOCK OPEN Command.

(26) With a relay 168 that boots up and before closing a network protector 166, the relay 168 can review stored information and adhere to a BLOCK OPEN command provided to the relay 168 to not close the network protector 166 until the BLOCK OPEN command is rescinded with an unblock command. The BLOCK OPEN command may be have provided because equipment needs maintenance or for some other reason. The relay 168 is attentive to other commands such as trip or Relax Open.

(27) Checking for Cross Phased Cables

(28) A booted and functional relay 168 can check the relative phase relationships of the energized cables on the transformer side of the network protector 166 to ensure that the phase relationship is consistent with the gross historical relationships. This will detect cables that were connected across phases when they were replaced during maintenance.

(29) By having the relay 168 booted and functional, a crossed phase set of cables on the network side 118 of the network protector 166 may be detected as soon as the network protector 166 closes and provides power to the local network 116. By providing power to the relay 168 before closing the network protector 166, the relay 168 can act to quickly open the network protector 166 until the phase issues can be corrected.

(30) Communications with Sub-Station.

(31) By powering up the relay 168 before closing the controlled network protector 166, the relay 168 may gather information which is relevant to assessing local conditions and convey that via power line carrier or some other communication channel to a control station at a sub-station or some other location. Conversely, applying power to the relay 168 and waiting for the relay 168 to become fully functional before closing the network protector 166 allows remote commands from power line carrier, wired, or fiber communication to interact with the relay 168.

(32) Connections for GE Power for 125 v/216 v Service.

(33) Those of skill in the art know that there is a longstanding split in conventions between Westinghouse type equipment and General Electric type equipment. Turning to FIG. 6, various components of interest are shown in limited detail. In the world of GE type equipment the connections between a relay and the network protector 166 typically had a trip connection, a close connection, and a common The common was actually connected to one of the three phases between the transformer 150 and the network protector 166. The connection was frequently to the A phase but any of the three phases will work for the purpose of providing power to the relay 168. Thus, this legacy connection that was not used to provide power to the relay 168 may be repurposed. Thus, the three phases on the network side 118 of the network protector 166 and the one phase on the transformer side of the network protector 166 can all be connected together as all four points have 125 v/216 v service. One of skill in the art knows that for three phase service, the voltage may be described by phase to ground (125 v) or phase to phase (216 v) or both to be absolutely clear.

(34) A set of diodes 1004 on the local network side and a diode 1016 on the transformer side may be used to limit power flow in one direction so that a bypass is not established around the network protector 166. Those of skill in the art will recognize that the single element diodes may be replaced by a set of components that serves to limit the flow of power in the desired direction. While it is likely that the three diodes 1004 are the same components, diode 1016 may be implemented differently than diodes 1004.

(35) Connections for GE Power for 277 v/480 v Service.

(36) For a local network that is operated at 277 v/480 v and using 125 v power for the relay 168, taking power from either side of the network protector 166 would be a problem unless there was a voltage reduction unit. As it was part of the prior art to provide power to relay 168 from the network side 118 of the network protector 166, the prior art already provides a voltage reduction unit 1012. Those of skill in the art will recognize that there are many known ways to reduce voltage including the use of transformers and various voltage regulators. It is not relevant for purposes of this present disclosure which is used.

(37) Those of skill in the art will recognize that for a relay that is operated with 277 volt inputs, the diagram for use of such a relay in a 277 v/480 v system may be implemented in a manner such as shown in FIG. 6 without voltage reduction from 277 volts to 125 volts.

(38) Voltage Reduction Unit.

(39) As shown in FIG. 7, to add the capacity to obtain power from the transformer side of the network protector 166, a voltage reduction unit 1008 is added. The type of voltage reduction unit 1008 used for voltage reduction unit 1008 may be the same type used in voltage reduction unit 1012 or may be a different type. The voltage reduction unit 1008 may be integrated into the housing of relay 168. Diode 1016 is on the inlet side of the voltage reduction unit 1008 and diode 1020 is on the outlet side of voltage reduction unit 1008 to prevent backfeed into the voltage reduction unit 1008. The power input to the relay 168 can be though any conventional port type such as a connector pin and socket combination.

(40) One of skill in the art will appreciate that if a relay 168 has an integrated voltage reduction unit 1008 and is placed in service with a 125 v/216 v system, then the voltage reduction unit will not have any reducing to do and the power will flow through the voltage reduction unit 1008 without substantial changes.

(41) Use of Network Voltage Detector and Shutoff

(42) The operation of the voltage reduction unit 1008 reducing voltage of power taken from the transformer side of the network protector 166 is not necessary if there is already power from the network side 118 of the network protector 166. As operation of a voltage reduction unit 1008 will give off heat, the components in FIG. 8 have added functionality to turn off this voltage reduction unit 1108 when the voltage reduction unit 1108 is not needed. As most of the time, the local network is not dead, most of the time, the voltage reduction unit 1008 is not needed.

(43) A network voltage detector 1118 can use any conventional measures to ascertain that at least one phase of the network on the network side 118 of the network protector 166 is energized. If at least one phase is energized, then the network voltage detector 1118 causes voltage reduction unit 1108 to shutoff. When all three phases of the network on the network side 118 of the network protector 166 are no longer energized, the network is dead and the network voltage detector 1118 ceases inhibition of the voltage reduction unit 1108 with shutoff Thus, whenever the network goes dead, the relay 168 receives power from the transformer side of the network protector 166, if power is available.

(44) Note the voltage detector 1118 inputs need to be connected on the local network side of the diodes 1004 so that the diodes 1004 isolate the voltage detector 1118 from the voltage that passed through diode 1020 after voltage reduction unit 1108.

(45) Diode 1020 keeps power that passes through diodes 1004 from feeding back into the circuitry of the voltage reduction unit 1108.

(46) The legal limitations of the scope of the claimed invention are set forth in the claims that follow and extend to cover their legal equivalents. Those unfamiliar with the legal tests for equivalency should consult a person registered to practice before the patent authority which granted this patent such as the United States Patent and Trademark Office or its counterpart.