Pole-mountable electricity supply apparatus

Abstract

A pole-mountable electricity supply apparatus 20 comprises an input 22 for receiving an electricity supply 12 from a pole-mounted electricity distribution transformer 16 and an output 24 for providing the electricity supply 18 to consumers’ premises. The apparatus 20 further comprises remotely controlled disconnect circuitry 26 which, in response to a disconnect command received from a remote location, disconnects the output 24 from the input 22. This can allow overhead cables between the transformer 16 and consumers’ premises to be remotely disconnected from the distribution network.

Description

The present invention relates to a pole-mountable electricity supply apparatus. The invention also relates to utility poles and electricity distribution networks which incorporate pole-mounted electricity supply apparatus. The invention also relates to methods of operating electricity distribution networks which make use of pole-mounted electricity supply apparatus. In the UK, Distribution Network Operators (DNOs) are publicly licenced operators responsible for interfacing between the National Grid and consumers’ premises. Consumers’ premises are typically supplied with electricity at a nominal phase voltage of 230V (-6%+10%). This may either be provided as a three phase supply with a nominal line voltage of 400V (-6%+10%) or as a single phase supply. The electricity supply is often distributed overhead using utility poles, typically as a high voltage (HV) three phase supply with a nominal line voltage of 11kV (-6+6%), or 6.6kV in some legacy distribution networks. This high voltage electricity supply is then converted to a low voltage (LV) electricity supply at a pole-mounted transformer near consumers’ premises. The low voltage electricity supply may then be provided to the consumers’ premises via overhead cables. The high voltage distribution network contains numerous apparatus for disconnecting parts of the network, for example when there are faults, emergency disconnections or when planned outages are required. However, using such apparatus on the high voltage distribution network can cause wide network outage. It is therefore desired to provide improvements relating to the supply of electricity. 31 01 24 According to an aspect of the present invention, there is provided a utility pole having mounted thereon an electricity distribution transformer and an electricity supply apparatus, the apparatus comprising: an input configured to receive an electricity supply from the pole-mounted electricity distribution 5 transformer; an output configured to provide the electricity supply to one or more consumers’ premises; a receiver configured to receive a disconnect command from a remote location; and remotely controlled disconnect circuitry configured to, in response to the disconnect command, disconnect the output from the input. As will be appreciated, embodiments of the present invention can allow 10 one or more overhead cables between a pole-mounted transformer and one or more consumers’ premises to be remotely disconnected from the distribution network. This in turn provides a quick and efficient way to mitigate a potentially dangerous incident on the low voltage electricity supply without the need to switch off sections of the high voltage distribution network. 15         In embodiments, the apparatus may comprise a pole-mountable enclosure having components of the apparatus housed therein. The enclosure may comprise an openable cover to allow access to the components of the apparatus housed therein. The enclosure may be mountable to a utility pole using mechanical fixings, such as screws, bolts and / or clamps. For example, the 20 enclosure may have apertures for receiving mechanical fixings therethrough. In embodiments, the electricity supply may be a “low voltage” or “LV” electricity supply as defined by the International Electrotechnical Commission (IEC). The nominal phase voltage of the electricity supply may be < 1kV, for example 230V (-6%+10%). The electricity supply may be a three phase supply. 31 01 24 The nominal line voltage of the electricity supply may be 400V (-6%+10%). Alternatively, the electricity supply may be a single phase supply. As discussed above, the remotely controlled disconnect circuitry is configured to, in response to the disconnect command, disconnect the output 5 from the input. In embodiments, disconnecting the output from the input may comprise disconnecting all phases of the output respectively from all phases of the input. Disconnecting the output from the input may also comprise disconnecting a neutral of the output from a neutral of the input. These embodiments can allow full disconnection of the output from the input. 10         In embodiments, the remotely controlled disconnect circuitry may comprise a circuit breaker, such as an air circuit breaker (ACB) or a moulded case circuit breaker (MCCB). The remotely controlled disconnect circuitry may be operated remotely by a motor and / or relay. These embodiments can provide reliable remote operation of the disconnect circuitry. The disconnect circuitry may 15 also be operated by a trip coil under trip conditions. In embodiments, the receiver may be further configured to receive a reconnect command from a remote location. The remotely controlled disconnect circuitry may be configured to, in response to the reconnect command, reconnect the input to the output. Again, reconnecting the input to the output may comprise 20 reconnecting all phases of the input respectively to all phases of the output. Reconnecting the input to the output may also comprise reconnecting a neutral of the input to a neutral of the output. In embodiments, the (disconnect and / or reconnect) command(s) may be received wirelessly. Thus, the receiver may comprise a wireless receiver. The 31 01 24 receiver may use any desired and suitable wireless protocol, such as a mobile communications protocol (e.g., 3G, 4G, 5G, etc.). In embodiments, the apparatus may further comprise detector circuitry for detecting the status of the electricity supply, for example on the output side of the 5 apparatus (e.g. on the output side of the remotely controlled disconnect circuitry). Detecting the status may comprise detecting one or more phase faults in the electricity supply. The detector circuitry may comprise one or more voltage monitoring relays. For example, the detector circuitry may comprise a voltage monitoring relay for each phase of the electricity supply. The apparatus may 10 further comprise a transmitter for transmitting the status to a remote location. The status may be transmitted wirelessly. Thus, the transmitter may comprise a wireless transmitter (e.g. a transceiver which also acts as the receiver). Again, the transmitter may use any desired and suitable wireless protocol, such as a mobile communications protocol (e.g., 3G, 4G, 5G, etc.). 15         The above embodiments can help to ensure safe disconnection by confirming that the electricity supply on the output side of the apparatus is at substantially zero volts following the command to disconnect the output from the input. These embodiments can also assist in fault finding in other sections of the distribution network, for example by identifying one or more phase faults / loss in 20 the apparatus despite the input being connected to the output. In any of the above embodiments, components (e.g. receiver, transmitter, controller, etc.) of the apparatus may be powered from the electricity supply, for example from the input side of the apparatus (e.g. from the input side of the remotely controlled disconnect circuitry). The apparatus may accordingly be 31 01 24 powered from the electricity supply even when the output is disconnected from the input. The apparatus may comprise one or more power supply units for converting the electricity supply to a power supply for the apparatus. For example, each phase of the electricity supply may drive a respective power supply unit for 5 the apparatus. The power supply units may be connected to a common power bus for the apparatus. This can help to maintain the power supply for the apparatus even if only one of the phases of the electricity supply is available. Each power supply unit may comprise an AC-DC converter, for example comprising a transformer (to step down the AC voltage) and / or a rectifier (to 10 convert from AC to DC). The nominal voltage of the power supply for the apparatus may be an “extra low voltage” or “ELV” as defined by the International Electrotechnical Commission (IEC). The nominal voltage of the power supply for the apparatus may be < 120V DC, for example 24V DC. In embodiments, the apparatus may comprise a controller for controlling 15 the operation of the apparatus. The controller may receive one or more commands from the receiver and instruct the disconnect circuitry to disconnect or reconnect accordingly. The controller may receive one or more status from the detector circuitry and instruct the transmitter to transmit the one or more status accordingly. The controller may comprise a programmable logic controller (PLC). 20 The remote location may be a control centre of a Distribution Network Operator (DNO). According to another aspect of the present invention, there is provided a pole-mountable electricity supply apparatus for mounting on a utility pole as described herein in any aspect or embodiment, the apparatus comprising: an 31 01 24 input configured to receive an electricity supply from a pole-mounted electricity distribution transformer; an output configured to provide the electricity supply to one or more consumers’ premises; a receiver configured to receive a disconnect command from a remote location; and remotely controlled disconnect circuitry 5 configured to, in response to the disconnect command, disconnect the output from the input. According to another aspect of the present invention, there is provided an electricity distribution network comprising plural electricity supply apparatus as described herein in any aspect or embodiment, each apparatus being mounted 10 on a respective utility pole of the network. According to another aspect of the present invention, there is provided an electricity distribution network comprising plural utility poles as described herein in any aspect or embodiment. In embodiments, the electricity distribution transformer may be configured 15 to receive a high voltage electricity supply, convert the high voltage electricity supply to a low voltage electricity supply, and provide the low voltage electricity supply to the input of the apparatus. As will be appreciated, the terms “high voltage” and “low voltage” used herein are relative to one another. The terms “high voltage” and “low voltage” are also terms defined by the International 20 Electrotechnical Commission (IEC), where “high voltage” or “HV” is defined as > 1 kV AC and “low voltage” or “LV" is defined as < 1 kV AC. In embodiments, the electricity distribution transformer may be configured to receive a three phase high voltage electricity supply. The nominal line voltage of the high voltage electricity supply may be > 1 kV, for example at least 6.6kV (- 31 01 24 6%+6%), for example at least 11 kV (-6%+6%). The nominal phase voltage of the low voltage electricity supply may be < 1kV, for example 230V (-6%+10%). The electricity distribution transformer may be configured to provide a three phase low voltage electricity supply. The nominal line voltage of the low voltage electricity 5 supply may be < 1kV, for example 400V (-6%+10%). Alternatively, the electricity distribution transformer may be configured to receive, convert and / or provide a single phase electricity supply. According to another aspect of the present invention, there is provided a method of electricity distribution using an electricity supply apparatus as 10 described herein in any aspect or embodiment or using a utility pole as described herein in any aspect or embodiment. In embodiments, the method may comprise transmitting, to a receiver of the apparatus, a command to disconnect the output from the input. The method may comprise receiving, from the apparatus, a status of the electricity supply. 15 The method may further comprise repairing an electricity supply to one or more consumers’ premises, for example whilst the output is (e.g. confirmed as being) disconnected from the input. The method may further comprise transmitting, to the receiver of the apparatus, a command to reconnect the input to the output, for example after the repair has been completed. 20         By way of example only, embodiments of the invention will now be described in detail with reference being made to the accompanying drawings in which: Figure 1 shows a section of a typical electricity distribution network; 31 01 24 Figure 2 shows a section of an electricity distribution network comprising an electricity supply apparatus according to an embodiment of the present invention; Figure 3 is a perspective view of the electricity supply apparatus; 5          Figure 4 is a perspective view of the electricity supply apparatus with its cover removed; Figure 5 is a front view of the electricity supply apparatus with its cover removed; Figure 6 is a simplified circuit diagram of the electricity supply apparatus; 10 and Figure 7 illustrates various electricity supply apparatus being used to locate a fault. Figure 1 shows a section of a typical electricity distribution network 2. The network 2 comprises a three phase electricity supply 3 having a nominal line 15 voltage of 11kV (-6%+6%). The network 2 also comprises plural utility poles 4 each having an electricity distribution transformer 5 mounted thereon. Although only one pole and transformer are referenced in the drawings, plural similar poles and transformers are shown. The transformer 5 converts the 11kV electricity supply to a three phase electricity supply 6 having a nominal line voltage of 400V 20   (-6%+10%) and a nominal phase voltage of 230V (-6%+10%), which is to be provided to one or more consumers’ premises. In this case, there is a fault on the low voltage electricity supply 6 (indicated with the lightning bolt). For example, a cable of the low voltage electricity supply 6 may have broken and may be in contact with the ground. To make the low voltage electricity supply 6 safe, and to 31 01 24 allow the fault to be disconnected and later repaired, a high voltage switch 7 on the high voltage electricity supply 3 is opened to disconnect power from the low voltage electricity supply 6 in question. However, in doing this, the entire section of the network 2 shown in Figure 1 is switched off, causing disruption to a much 5 greater number of consumers’ premises than that which is directly affected by the low voltage incident. Figure 2 shows a section of an electricity distribution network 10 according to an embodiment of the present invention. The network 10 again comprises a three phase electricity supply 12 having a nominal line voltage of 11kV (-6%+6%). 10 The network 10 also comprises plural utility poles 14 each having an electricity distribution transformer 16 mounted thereon. Again, although only one pole and transformer are referenced in the drawings, plural similar poles and transformers are shown. The transformer 16 again converts the 11kV electricity supply to a three phase electricity supply 18 having a nominal line voltage of 400V (- 15  6%+10%) and a nominal phase voltage of 230V (-6%+10%), which is to be provided to one or more consumers’ premises. Again, there is a fault on the low voltage electricity supply 18 (indicated with the lightning bolt). However, in this embodiment, to make the low voltage electricity supply 18 safe, and to allow the fault to be disconnected and later repaired, a pole-mounted electricity supply 20 apparatus 20 is provided. The apparatus 20 comprises a three phase input 22 that receives the low voltage electricity supply from the transformer 16 and a three phase output 24 that provides the low voltage electricity supply 18 to the one or more consumers’ premises. The apparatus 20 also comprises a transceiver 25 that receives a disconnect command from a remote location, for example from 31 01 24 the Distribution Network Operator (DNO) responsible for the network 10 in question. The apparatus 20 also comprises remotely controlled disconnect circuitry 26 which, in response to the disconnect command, disconnects the output 24 from the input 22 to disconnect power from the low voltage electricity 5 supply 18. In this way, only the part of the network 10 which is directly affected by the fault is switched off. Once the fault is repaired, the remotely controlled disconnect circuitry 26 reconnects the input 22 to the output 24 in response to a reconnect command received from the remote location. Although only one apparatus 20 is shown in the drawings, similar apparatus may be provided on 10 each utility pole. Figure 3 is a perspective view of the pole-mountable electricity supply apparatus 20. As is shown, the apparatus 20 comprises an enclosure 28 having an openable hinged cover 30 to allow access to the components of the apparatus 20 contained therein. Figures 4 and 5 show the apparatus 20 with the cover 30 15 removed. As is shown, the enclosure 28 comprises apertures 32, which allow the enclosure 28 to be mounted to the utility pole using screws. Referring now to Figures 5 and 6, as discussed above, the apparatus 20 comprises a three phase input 22 that receives the low voltage electricity supply from the transformer 16 and a three phase output 24 that, under normal operating 20 conditions, provides the low voltage electricity supply 18 to the one or more consumers’ premises. The apparatus 20 also comprises remotely controlled disconnect circuitry 26 in the form of a moulded case circuit breaker (MCCB), although other forms of disconnect circuitry may be used. The disconnect circuitry 26 is configured to disconnect all phases and the neutral of the electricity supply. 31 01 24 The control components of the apparatus 20 are powered by power supply units 34 connected to a common power bus 35. The power supply units 34 transform and then rectify the AC electricity supply so as to produce a 24V DC power supply. A power supply unit is provided for each phase, such that the 24V DC 5 power supply can be maintained even if only one of the phases is available. Operation of the apparatus 20 is controlled by a controller 36, which in this embodiment is a programmable logic controller (PLC). The controller 36 receives commands from the transceiver 25 via an ethernet cable (not shown) and instructs the disconnect circuitry 26 to disconnect or reconnect accordingly. In 10 this embodiment, the disconnect circuitry 26 is operated using a motor relay 38, which in turn operates an MCCB motor 40 that forms part of the disconnect circuitry 26. The disconnect circuitry 26 also has the ability to emergency trip via an extra low voltage (ELV) or 24v DC shunt trip coil in the MCCB in the event of a phase loss that reduces or eliminates the ability to use the disconnect function 15 via the MCCB motor 40. The apparatus 20 also comprises detector circuitry 42 in the form of voltage monitoring relays, which confirm the connected / disconnected status of the electricity supply on the output side of the remotely controlled disconnect circuitry 26 by detecting the presence / absence of a substantially nonzero voltage in the electricity supply on the output side of the disconnect circuitry 20   26. The controller 36 receives the status from detector circuitry 42 and instructs the transceiver 25 to transmit the status to the remote location accordingly to allow for remote monitoring. The apparatus 20 also comprises protection circuitry, in this case in the form of a surge arrestor 44 to protect against transient spikes (e.g. caused by lightning or switching). The surge arrestor 44 is shown as 31 01 24 semiconductor in nature, but metal oxide varistors (MOVs) may be used in practice. The apparatus also comprises further protection circuitry in the form of fuses 46, a miniature circuit breaker (MCB) 48 for the power supply unit 34, a miniature circuit breaker (MCB) 50 for the surge arrestor 44, and isolation diodes 5   51 for the power supply units 34. Figure 7 illustrates plural pole-mounted electricity supply apparatus 20a-c being used to locate a fault in a section of an electricity distribution network 52. The apparatus 20a-c are all operating in a connected state and thus, under no fault conditions, there should be no phase faults / loss. However, in this 10 embodiment, a fault lies between a first part 12a of the high voltage electricity supply 12 and a second part 12b of the high voltage electricity supply 12. To locate that fault, high voltage switches 17a and 17b remain closed and high voltage switch 17c remains open. Under these circumstances, apparatus 20a provides status information indicating no phase faults / loss on any of its output 15 lines, whereas apparatus 20b and 20c each indicate a phase fault / loss on output line L1. This indicates that there is a likely phase fault / loss on the L1 line of the high voltage electricity supply 12 somewhere between the first part 12a of the high voltage electricity supply 12 (i.e. which supplies apparatus 20a) and the second part 12b of the high voltage electricity supply 12 (i.e. which supplies 20 apparatus 20b and 20c). The fault on the high voltage electricity supply 12 can therefore be rapidly located and repaired based on the transmitted status information.

Claims

1. A utility pole having mounted thereon an electricity distribution transformer and an electricity supply apparatus, the apparatus comprising: an input 5 configured to receive an electricity supply from the pole-mounted electricity distribution transformer; an output configured to provide the electricity supply to one or more consumers’ premises; a receiver configured to receive a disconnect command from a remote location; and remotely controlled disconnect circuitry configured to, in response to the disconnect command, disconnect the output 10 from the input.

2. A utility pole as claimed in claim 1, wherein the apparatus comprises a pole-mountable enclosure having components of the apparatus housed therein.

3. A utility pole as claimed in claim 2, wherein the enclosure comprises an openable cover to allow access to the components of the apparatus housed 15 therein.

4. A utility pole as claimed in claim 1, 2 or 3, wherein the nominal phase voltage of the electricity supply is < 1 kV.

5. A utility pole as claimed in any one of the preceding claims, wherein the electricity supply is a three phase supply.20   6. A utility pole as claimed in any one of the preceding claims, wherein thenominal line voltage of the electricity supply is < 1 kV.

7. A utility pole as claimed in any one of the preceding claims, wherein disconnecting the output from the input comprises disconnecting all phases of the output respectively from all phases of the input.31 01 248. A utility pole as claimed in any one of the preceding claims, wherein disconnecting the output from the input comprises disconnecting a neutral of the output from a neutral of the input.

9. A utility pole as claimed in any one of the preceding claims, wherein the 5 remotely controlled disconnect circuitry comprises a circuit breaker.

10. A utility pole as claimed in any one of the preceding claims, wherein the remotely controlled disconnect circuitry comprises an air circuit breaker (ACB) or a moulded case circuit breaker (MCCB).

11. A utility pole as claimed in any one of the preceding claims, wherein the 10 receiver is further configured to receive a reconnect command from a remote location and the remotely controlled disconnect circuitry is configured to, in response to the reconnect command, reconnect the input to the output.

12. A utility pole as claimed in claim 11, wherein reconnecting the input to the output comprises reconnecting all phases of the input respectively to all phases 15 of the output.

13. A utility pole as claimed in claim 11 or 12, wherein reconnecting the input to the output comprises reconnecting a neutral of the input to a neutral of the output.

14. A utility pole as claimed in any one of the preceding claims, wherein the 20 disconnect command is received wirelessly.

15. A utility pole as claimed in any one of the preceding claims, the apparatus further comprising detector circuitry for detecting the status of the electricity supply on the output side of the apparatus.31 01 2416. A utility pole as claimed in claim 15, wherein detecting the status comprises detecting one or more phase faults in the electricity supply.

17. A utility pole as claimed in claim 15 or 16, wherein the detector circuitry comprises one or more voltage monitoring relays.5   18. A utility pole as claimed in claim 15, 16 or 17, the apparatus furthercomprising a transmitter for transmitting the status to a remote location.

19. A utility pole as claimed in any one of the preceding claims, wherein components of the apparatus are powered from the input side of the electricity supply.10   20. A utility pole as claimed in any one of the preceding claims, wherein eachphase of the electricity supply drives a respective power supply unit for the apparatus.

21. A pole-mountable electricity supply apparatus for mounting on a utility pole as claimed in any one of claims 1-20, the apparatus comprising: an input 15 configured to receive an electricity supply from a pole-mounted electricity distribution transformer; an output configured to provide the electricity supply to one or more consumers’ premises; a receiver configured to receive a disconnect command from a remote location; and remotely controlled disconnect circuitry configured to, in response to the disconnect command, disconnect the output 20 from the input.

22. An electricity distribution network comprising plural electricity supply apparatus as claimed in claim 21, each apparatus being mounted on a respective utility pole of the network.

23. An electricity distribution network comprising plural utility poles as claimed in any one of claims 1 -20.

24. A method of electricity distribution using an electricity supply apparatus as claimed in claim 21 or using a utility pole as claimed in any one of claims 1-20.31 01 24

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