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Flexible Urban Networks – Low Voltage Successful completion of design and planning for power electronics devices (SDRC 9.1)

FUN-LV SDRC 9.1

UK Power Networks (Operations) Limited. Registered in England and Wales. Registered No. 3870728. Registered Office: Newington House, 237 Southwark Bridge Road, London, SE1 6NP of 22

Contents

Executive Summary ............................................................................................................................ 4

1. Introduction ................................................................................................................................ 5

1.1 Background ..................................................................................................................... 5

1.2 Report Scope and Objective ........................................................................................... 5

2. Guidance document ................................................................................................................... 7

3. Key learning and planning considerations ................................................................................. 8

3.1 Key learning .................................................................................................................... 8

3.1.1 Network awareness ........................................................................................................ 8

3.1.2 Network records require site visits.................................................................................. 8

3.1.3 Physical characteristics .................................................................................................. 8

3.1.4 Transformer demand data .............................................................................................. 9

3.1.5 Asset data ....................................................................................................................... 9

3.1.6 Planning Tools ................................................................................................................ 9

3.1.7 Construction (Design and Management) Regulations 2007 (CDM) ............................. 10

3.1.8 Local authority contact .................................................................................................. 10

3.1.9 Physical connection arrangements............................................................................... 10

3.1.10 Method 1 developments from original concepts ........................................................... 11

3.1.11 Existing interconnected network issues ....................................................................... 11

3.1.12 Fault level contribution .................................................................................................. 12

3.1.13 Cable ratings ................................................................................................................. 12

3.1.14 Studies on LPN interconnected networks .................................................................... 13

3.1.15 DPlan modelling............................................................................................................ 13

3.2 Planning considerations ............................................................................................... 14

3.2.1 FUN-LV process ........................................................................................................... 14

3.2.2 FUN-LV Method limitations ........................................................................................... 15

4. Identified substations ............................................................................................................... 17

4.1 SPN selected sites........................................................................................................ 17

4.2 LPN Radial selected sites ............................................................................................. 18

4.3 LPN interconnected selected sites ............................................................................... 19

5. Sources of data ........................................................................................................................ 21

Appendix A – Guidance Document – Traditional Planning Considerations for Power

Electronics Devices .......................................................................................................................... 22

Appendix B – Selection Criteria and Approach ................................................................................ 22

Appendix C – DPlan: Support for site selection ............................................................................... 22

Table of figures

Figure 1 3D-Model of Method 3 PED ...................................................................................................... 8

Figure 2 Link box controller positioned above the LBSs ......................................................................... 9

Figure 3 Remote control circuit breakers .............................................................................................. 11

Figure 4 3D-Model of Method 2 PED .................................................................................................... 11

Figure 5 PowerLock system used for the multi-terminal PED ............................................................... 11

Figure 6 Earth fault ................................................................................................................................ 12

Figure 7 Open circuit fault ..................................................................................................................... 12

Figure 8 DNV customer type load profiles ............................................................................................. 14

Figure 9 DNV substation locations with profile type .............................................................................. 15

FUN-LV SDRC 9.1


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FUN-LV SDRC 9.1


Executive Summary The overarching aim of the Flexible Urban Networks at Low Voltage (FUN-LV) project is to explore the

use of power electronics devices to enable deferral of reinforcement and facilitate the connection of

low carbon technologies and distributed generation in urban areas, by meshing existing networks

which are not currently meshed, and by removing boundaries within existing meshed networks.

During 2014 UK Power Networks has sourced the power electronics devices ready for installation by

the end of Q2 2015. To be able to demonstrate the benefits, a site selection process has been

undertaken. A guidance document – Traditional Planning Considerations for Power Electronics

Devices has been produced using existing planning tools. The key learning confirms that the FUN-LV

project plan to improve the visibility of LV networks will be essential to identify the best situations in

which to deploy power electronics devices, and the effective increase in capacity sharing that can be

achieved.

This report details the necessary and sufficient evidence to complete Successful Delivery Reward

Criteria (SDRC) 9.1 “Successful completion of design and planning for power electronics devices”.

FUN-LV SDRC 9.1


1. Introduction

1.1 Background

Efforts to decarbonise energy generation and heat and transport will place increasing demands on

distribution networks, particularly so for the low voltage (LV) networks closest to our customers, where

DNOs have the obligation of supplying customers their electricity demand, within tightly defined

voltage limits which their devices have been designed to expect, and at a sufficient quality (harmonics,

sags, swells and flicker).

Interconnected networks offer one potential part of the answer. In interconnected networks, customers

are supplied by two or more different routes through the LV network, with the result that their demand

can be shared across substations. This reduces loading on transformers, tends to suppress voltage

fluctuations, reduce losses, and customers benefit from in-built resilience to high voltage (HV) network

faults. UK Power Networks has run some parts of its networks meshed for many years using LV air

circuit breakers and fuses. In urban and central business districts, both in UK Power Networks and

other DNOs, there is potential for further meshing.

The overarching aim of the FUN-LV project is to explore the use of power electronics devices (PED) to

enable deferral of reinforcement and facilitate the connection of low carbon technologies and

distributed generation in urban areas, by meshing existing networks which are not meshed, and by

removing boundaries within existing meshed networks. Power electronics allows both the reversion of

the network to two radial networks in the event of a fault and separately it can, in some cases, offer full

control over how much load is shared between substations.

The FUN-LV trials demonstrate three different Methods with increasing levels of capacity sharing

functionality. Method 1 uses remote control circuit breakers and link box switches developed by TE

Connectivity and supplied under licence by EA Technology Ltd. The link box switches (LBS) replace

the solid links in the link box. This equipment joins substations together providing uncontrolled levels

of current flow. Methods 2 and 3 use two or three back-to-back power inverters, respectively, with a

common DC busbar. The inverters are controlled by an autonomous control system that calculates

the level of power flow across the DC busbar. Each inverter is able to import or export, real and

reactive power between different AC LV networks and the DC busbar dependent on how the inverter

is switched. Methods 1 and 3 are installed within distribution substations whereas Method 2 is

installed as a piece of street furniture.

UK Power Networks’ distribution planners have been involved throughout the selection process, giving

insights into the challenges of connecting new customer connections without depleting the security of

supply enjoyed by existing customers. Planning studies have been carried out to demonstrate to the

distribution planners that the FUN-LV Methods do provide capacity sharing, voltage support, fault level

control and maintain the expected levels of the security of supply.

1.2 Report Scope and Objective

This report details the necessary and sufficient evidence to complete Successful Delivery Reward

Criteria (SDRC) 9.1 “Successful completion of design and planning for power electronics devices”:

FUN-LV has published a guidance document on planning considerations for selecting, designing and installing power electronics devices using the traditional planning systems and approaches currently used by UK Power Networks. This guidance document can be found in Appendix A.

FUN-LV has identified some key learning and planning considerations necessary to demonstrate the power electronics device functionality. The learning is described within this document and demonstrated through case studies contained in Appendix A.

FUN-LV SDRC 9.1


Using the approaches discussed above, FUN-LV has created a list of identified substations that will host the three different types of power electronics device trials, a document defining the selection criteria and a matrix listing the expected benefits in Appendix B.

The target audience for this report is other distribution network operators who may be looking to

understand the planning considerations necessary to deploy further examples of power electronics

devices.

FUN-LV SDRC 9.1


2. Guidance document

The guidance document “Traditional Planning Considerations for Power Electronic Devices” describes

the different distribution planning tools UK Power Networks currently has available to plan and design

LV distribution networks. It details how FUN-LV has used these traditional planning tools and the

recently developed Distribution Network Visibility (DNV) tool funded using the Low Carbon Networks

Fund to assist in the identification of candidate sites that could be used to demonstrate and realise the

benefits of the FUN-LV trials.

A copy of the guidance document can be found in Appendix A.

The guidance document describes the applications available to allow distribution planners to analyse a

section of LV distribution network. Transformer demand increases naturally as connected customers

increase their electricity usage. This increase has historically been 1% per annum. However step

changes in demand are triggered by connection requests. In LPN a connection request is referred to

the distribution planning team, for study using planning tools, if the connection request is greater than

140kW. This detailed analysis is required to ensure network resilience and particularly on existing

interconnected networks where unanalysed increases in demand could result in collapse of the

meshed LV networks supplying customers.

Other reasons that may require distribution planning analysis are voltage complaints. Traditionally the

supply quality team install monitoring equipment for a couple of weeks and then make a decision on

whether the complaint is justified. Justified complaints can be resolved using a number of

reconfiguration techniques. In some cases reinforcement is required.

Annual substation inspections have sometimes triggered the need for further investigations. One

example is when substation inspectors have reported that the substation ambient temperature is hot

and have recorded high maximum demands. In LPN over 54% of secondary substations have a

remote terminal unit (RTU) installed and transformer utilisation and substation ambient temperature

have been monitored for several years. The DNV tool has allowed distribution planners to quickly

assess the duration of a recorded maximum demand and whether reinforcement is required.

The “Business As Usual Comparison Case Studies” contained in section 3 of Appendix A have been written to compare the traditional reinforcement scenarios driven by a hypothetical customer connection request or natural load growth, with an equivalent FUN-LV proposed trial solution.

Once a distribution planner has proposed a solution and it is approved it is then passed to the Network

Operations directorate to deliver. Conventional solutions may take several months to deliver, unless

the developer is providing the land to accommodate a distribution substation.

http://innovation.ukpowernetworks.co.uk/innovation/en/Projects/tier-1-projects/distribution-network-visibility/

FUN-LV SDRC 9.1


3. Key learning and planning considerations

3.1 Key learning

3.1.1 Network awareness

The LV network has traditionally been a passive system where field staff inspect and maintain substations and repair equipment after a fault. With the advent of LV monitoring systems (see close down report on the LV sensor evaluation project) there has been activity on developing tools to manage the data being collected. Different areas have had different drivers for the installation of remote control equipment and RTUs. In London a major driver has been access to substations out of office hours. Once the RTU has been installed it has been able to collect a few parameters (utilisation, ambient temperature, demand and voltage) that greatly assist Asset Management processes. Within UK Power Networks these parameters are stored in PI (a time series database from OSIsoft).

3.1.2 Network records require site visits

Our network records department uses a Geographical Information System (GIS) from GE Digital Systems known as Smallworld (colloquially Netmap) to store linear records. In London the majority of records are still a raster based image. Time-consuming analysis of cable routes is required to follow a LV cable from one substation to another. Fortunately our LPN planning tool DINIS contains the necessary data to determine the capacity available. The records show the location of the secondary substation but not which level it is to be found e.g. a basement, ground level or elevated. In SPN the network records are vector based records having the size and length stored with the diagram image. This allows data to be collected more quickly.

The FUN-LV results are therefore relevant to DNOs with an underlying GIS system recording network records, in vector or raster form, and those with network records in-built and mastered in their planning tools.

3.1.3 Physical characteristics

When carrying out the feasibility of installing large pieces of equipment, e.g. the FUN-LV Method 3, site visits are required. The size and location of the substation can be estimated from a Netmap diagram. However details such as: access to substations (e.g. size of doors, up flight of stairs, down in a basement, etc.); space available to provide necessary clearance around the PED; ventilation and thermal characteristics are not normally recorded. This is a time consuming activity where a survey can take several hours. Taking notes and photographs are important in the selection process.

Most secondary substations rely on natural ventilation. The installation of power electronics devices introduces an additional heat source of approximately 30kW. Forced ventilation has been designed.

Figure 1 3D-Model of Method 3 PED

http://innovation.ukpowernetworks.co.uk/innovation/en/Projects/tier-1-projects/low-voltage-current-sensor-technology-evaluation/

FUN-LV SDRC 9.1


The heat extraction system needs to be positioned where it will not cause inconvenience in the form of noise. Low speed fans have been specified.

3.1.4 Transformer demand data

In most DNOs, RTUs provide basic remote control and automation functionality of the high voltage switchgear in secondary substations. The collection of basic parameters apart from in LPN was not deemed necessary when the RTUs were first installed. In SPN transformer demand profiles were not available. To select candidate trial sites alternative methods to generate profiles were required. PPA Energy has developed a wireless transformer temperature sensor and algorithm to convert a measured temperature profile into an equivalent demand profile calibrated using the transformer’s maximum demand indicator. These derived profiles have been used to select the sites in the Brighton area and London substations without a RTU.

3.1.5 Asset data

Each link box is given a six character unique identifier which is recorded on Netmap. The Method 1 LBSs have been designed to be used in the modern link box supplied by Prysmian (Figure 2). When data stored in our asset management database, Ellipse, is interrogated there is insufficient information on whether the box is of the correct type or has sufficient clearance to accommodate the LBS and controller under the pavement cover. Site visits have therefore been required.

Figure 2 Link box controller positioned above the LBSs

3.1.6 Planning Tools

As is described in the guidance document, the traditional planning tools are able to carry out traditional

LV distribution network analysis. Traditional network components are linear devices and can be

modelled to allow worse case analysis to be carried out. With the introduction of power electronics

devices, a non-linear device, “Matlab type” models need to be developed to allow the impact of these

new devices to be understood. There is no longer a simple linear equation converting the conditions

at the terminals to the current flow through the PED. The PED algorithm controls the current flow.

Typical LV planning tools do not accommodate this and therefore workarounds with approximate

linear models or multiple simulations need to be made. The case studies in Appendix A further

demonstrate the application of traditional tools and planning considerations for selection, installing and

designing power electronic devices.

In FUN-LV the project intends to use DPlan, a planning tool developed by IOA, Portugal. IOA will develop PED models for DPlan. Network data will be extracted from LPN DINIS and SPN Netmap.

FUN-LV SDRC 9.1


Load data will be extracted from the historian PI. DPlan has demonstrated that it can perform load flow studies on simple interconnected networks, where other LV planning tools may not converge. Allocating substation and customer demand data into LV network models to allow analysis to take place has taken considerable configuration and time. The availability and immaturity of tools that will be used as part of the project were not fully appreciated, and time was required to understand how the tools can be used to interpret the results and validate results.

3.1.7 Construction (Design and Management) Regulations 2007 (CDM)

The installation of the equipment could be considered individual projects. However, our CDM co-ordinators advised that FUN-LV should be considered as a programme of trials and as such Notifiable, since the programme exceeds 500 man-days or 30 working days threshold. The project has therefore appointed a CDM co-ordinator to ensure compliance.

3.1.8 Local authority contact

The FUN-LV Method 2 is designed to be a pavement installation similar to a feeder pillar. As these devices are different to the typical street furniture UK Power Networks installs and they provide capacity sharing between substations, it was decided to make contact with the local authority, explain our intentions and understand their concerns. The units are to be installed using utility’s permitted development rights. To aid the conversations with the local authorities 3D montages were developed to show the street location with a mock-up of the cabinet options.

3.1.9 Physical connection arrangements

All three FUN-LV Methods have connections that allow the Method installation to be removed and the network returned to its original configuration without introducing customer interruptions. It is expected that each Method will defer capital reinforcement for a number of years. Eventually, subject to continued demand growth, a Method will need to be removed to allow an alternative Method to be deployed or conventional reinforcement to take place. The FUN-LV Method 1 involves the remote control circuit breakers (RCCB) and LBS (Figure 3). The RCCB are a direct replacement for the fuse carriers on a distribution board. The LBS replace the solid links within a link box. All equipment involved in this Method can be removed and the network returned to its original configuration.

Method 2 (Figure 4) involves the installation of a cabinet on the pavement. If it is necessary to isolate the device, then the circuit breakers within the cabinet can be opened and solid links removed. If the cabinet is to be permanently removed then two pot-ends will need to be made.

The size of the Method 2 cabinets, access for maintenance and ventilation and proximity of suitable LV circuits, constrain where they can be economically placed.

FUN-LV SDRC 9.1


Figure 3 Remote control circuit breakers

Figure 4 3D-Model of Method 2 PED

Method 3 device is installed within a secondary substation. The preferred connection uses VEAM PowerLock connectors and modified fuse carriers connected directly to the distribution board (Figure 5). The connections can be removed and the network returned to its original configuration.

Figure 5 PowerLock system used for the multi-terminal PED

3.1.10 Method 1 developments from original concepts

Site selection for Method 1 installations has been a more complex task than originally anticipated. A wide range of technical issues concerning the specification, rating, operational timings of RCCBs and LBSs, and adaptive protection for various applications needed to be fully understood and integrated into site selection and asset guarding systems.

In the bid the project had proposed joining a number of substations together. During the site selection process a number of normal open points were identified on LV distribution boards. In addition to the proposed Method 1, an alternative method referred to as “1c” with only RCCBs at each end of the LV feeder without any LBSs is being involved. This method allows capacity sharing and rapidly returns to the original configuration if a fault occurs.

3.1.11 Existing interconnected network issues

In the bid the project recognised that existing interconnected networks already share capacity. During the site selection process a number of standalone substations were identified. These substations are

FUN-LV SDRC 9.1


equivalent to radial substations embedded within the interconnected network. They are generally lightly loaded substations that could not be integrated into the interconnected network as inclusion of the demand could cause the collapse of the group of substations. A method is being trialled where the spare capacity available in these radial embedded substations is utilised by adding a set of RCCBs at the normal open point (Method 1) or installing a dual terminal PED (Method 2). In the event of a fault affecting the interconnected group the radial embedded substation is rapidly removed and the original interconnected group is able to support itself until the network returns to normal.

3.1.12 Fault level contribution

The PEDs have been designed to restrict the fault level contribution from the donor side. The unit will

only deliver the current determined by the demand algorithm. If an earth fault should occur on the

spine circuit then the PED stops conducting almost immediately. The fuses on the faulty phases clear

the fault. Supplies can be restored once the fault has been repaired.

A spine circuit describes the circuit between two substations that is used for capacity sharing.

If an open circuit fault occurs on one half of the spine circuit, then customers between the fault and the

PED cannot be supplied until the network is reconfigured or the fault is repaired because the PED

cannot deliver the necessary fault level contribution to ensure customers’ protective devices operate

for a fault on their side of the meter.

3.1.13 Cable ratings

Transfer profiles may be similar or very different to load profiles. ENA Engineering Recommendation P17 – ‘Current Ratings for Distribution Cables’ ratings are based on cyclic load profiles. Depending on the shape of the transfer profile this will determine whether a lower continuous current cable rating needs to be used.

Figure 6 Earth fault

Figure 7 Open circuit fault

FUN-LV SDRC 9.1


3.1.14 Studies on LPN interconnected networks

The RCCB fault break rating presents significant constraint to its widespread use in LV automation

and the replacement of conventional fringe fuses on interconnected networks. However the RCCB

adaptive protection (programmable protection characteristics) provides significant opportunities that

enable the use of Method 1 equipment for selected valuable applications in interconnected networks

especially for the connection of Radial Embedded Substations (RES) and the remote reconfiguration

of networks under non-fault conditions.

Preliminary fault level studies undertaken in DPlan have confirmed the importance of clear

visualisation of fault current directions and modelling of Method 1 adaptive protection characteristics.

The LBS requires a power supply to operate. The supply can be derived from healthy phases of the

circuit. However, if a three phase fault occurs then the supply has to be derived from the healthy side

of a NOP across a four way link box. There are relatively few link boxes on many sections of LV

networks that meet this requirement and limits the scope for Method 1 automation.

Most Interconnected networks have relatively few customers (but with very large loads) so LV CI/CML

benefits associated with LV network automation are comparatively small in relation to the economic

benefits provided to the customers where it can be economically demonstrated.

3.1.15 DPlan modelling

Existing UK Power Networks modelling tools do not have the ability to enable these studies and DPlan is being used by FUN-LV to investigate load transfer profiles. As part of the project the selected sites will be modelled in DPlan. Previous LCNF projects (Low Carbon London and Smart Urban Low Voltage Networks) have created DPlan network models and the underlying demand data. Some of the proposed sites are within the current networks modelled in DPlan. The DPlan models have been created from existing UK Power Networks’ data sets. The DPlan networks include modelling down to each customer connection point. As the DPlan models bring together data from a number of different sources this has shown some inconsistency between these data sources. These inconsistencies are identified and corrected in the source systems. Some assumptions are made about customer connection points because of the limited data available and these assumptions will be checked when validating the networks. As part of the project there are additional functions being developed in DPlan to model the different Methods and to perform the supporting analysis. These functions are not available yet and therefore the DPlan modelling analysis is limited to the current DPlan functionality. This has presented a number of short term challenges especially for accurate load allocation in the LPN interconnected networks. Fault level studies for all Methods are critically important, e.g. Method 1 accounting for sub-transient RCCB clearance times, the probability of types of LV faults, their durations and impacts of arc voltage on fault currents over clearance time. Nodal fault level survey results have limited use for FUN-LV applications. Existing DPlan functionality provides both nodal fault levels and maximum branch fault currents. Fault Level and power flow studies have been performed using DPlan for the some of the proposed sites. A process has been created for modelling Soft Open Points (SOPs) using the current set of DPlan functionality.

FUN-LV SDRC 9.1


3.2 Planning considerations

3.2.1 FUN-LV process

The FUN-LV Methods are expected to deliver differing amounts of capacity sharing between

substations. If half-hourly data from neighbouring substations is available load profiles can be created

using visualisation tools (e.g. Excel).

The FUN-LV project has been able to use the DNV tool to identify sites with high demand profiles that

could be resolved using FUN-LV Methods. However, if the demand is too high, there will not be an

opportunity to defer conventional reinforcement.

DNV is able to access load profile data that has been stored in the historian PI. Different load profile

types have been defined and DNV is able to classify each substation profile against a customer profile

type e.g. different types of residential and commercial profiles.

DNV is a tool designed to display data with geographical background. This quickly allows the planner

to view the areas where different load profiles can be found. Capacity sharing benefits can be

realised if two neighbouring substations have different load profiles based on either different types

of customer or demand utilisation.

Figure 8 DNV customer type load profiles

http://innovation.ukpowernetworks.co.uk/innovation/en/Projects/tier-1-projects/distribution-network-visibility/Project-Documents/DNV+CDR+Version+3.0+270214.pdfhttp:/innovation.ukpowernetworks.co.uk/innovation/en/Projects/tier-1-projects/distribution-network-visibility/Project-Documents/DNV+CDR+Version+3.0+270214.pdf

FUN-LV SDRC 9.1


Each of the three Methods being trialled allows increasing amount of capacity sharing. In the case of

Method 1 the sharing is a function of the impedance of the LV circuits and is controlled by the HV

infeeds, sizes of transformers, length and type of cable as well as by the size and disposition of point

and distributed loads.

An algorithm is being developed by Imperial College for Methods 2 and 3 that will use the demand

data from the substations connected to the PED to control the capacity sharing. This demand data is

either measured or derived using a LV monitoring system. In addition the system will ensure that the

ratings of the spine circuits are not exceeded.

It is expected that the benefit of each capacity sharing Method will reduce as the demand continues to

grow. FUN-LV expects that once a Method 1 no longer provides benefit then it could be replaced with

either Method 2 or 3 solutions and finally replaced by conventional reinforcement.

One of the challenges of distribution planning is to have an understanding of how quickly the demand

will grow. UK Power Networks has modelled demand growth based on DECC’s four scenarios and an

adopted hybrid or “core” planning scenario. Each scenario describes different rates of demand

growth. If the rate of increase is quick then there may not be sufficient time to realise the benefits of

the FUN-LV Methods.

In addition to the scenarios, city plans and redevelopment strategies may give a view of the rate of

increase. Some redevelopment strategies are phased over a number of years, describing the types of

customer including generation but even with these plans there is significant uncertainty. The demand

growth and PED models built into DPlan will allow planners to be able to know that the PED will help

in the short term, but will have uncertainty around for how long.

3.2.2 FUN-LV Method limitations

Methods 1 and 3 are realised by installing equipment within secondary substations. Only Method 2

which consists of a large cabinet (Figure 4) is installed on the pavement. Part of the planning process

is to check that the proposed electrical connection can be accommodated in the urban environment.

The width of the pavement is an important consideration. Any street furniture must not cause a

hazard to pedestrians especially those with wide pushchairs. The project has met with local authority

street works managers regarding the siting of these Method 2 solutions.

Figure 9 DNV substation locations with profile type

FUN-LV SDRC 9.1


Only Methods 2 and 3 can connect substations across primary substation boundaries. Method 1 can

only be used if the two substations are connected to the same primary substation or busbar section. If

Method 1 tries to straddle a substation boundary excessive circulating current may flow beyond the

rating of the spine circuit.

Additional functionality is being developed in the Method 1 RCCBs to guard against excessive reverse

powerflow due to an HV fault and an intertrip system to avoid supplying a transformer fault from the LV

side. An automation scheme is also being developed to isolate the faulty side of the spine circuit

allowing the healthy side to be restored. Fault levels need to be assessed to ensure that the RCCB

does operate as expected. For fault currents in excess of 6kA, the RCCB is inhibited and the fault is

cleared by the in-line fuse. In the event that the fuse does operate, the fuse will need to be replaced

before customer supplies can be restored. Customers’ quality of supply has not been degraded as

this situation is no different to existing network operations.

Further details on planning considerations are mentioned the guidance document in Appendix A.

FUN-LV SDRC 9.1


4. Identified substations

The FUN-LV field trials have been selected to demonstrate:

• 12 solutions in Brighton (four each of Methods 1, 2 and 3),

• 12 solutions in radial London networks (four each of Methods 1, 2 and 3), and

• 12 solutions in interconnected London networks (comprising elements of Methods 1, 2 and 3).

Where the Methods are:

• Method 1a: Remote control circuit breakers and link box switches in one link box.

• Method 1c1: Remote control circuit breakers only

• Method 2: Dual-terminal PED

• Method 3: Multi-terminal PED

The proposed trial sites are listed in the tables below, presented by location/network type and Method.

Most substations have one transformer [T1] only, but some have two or more transformers. [T1] and

[T2] in the tables below indicate which transformer is involved in the trial. The selection criteria for

selecting these sites are discussed in Appendix B. Substations A, B and C below are the locations

where equipment is being installed to facilitate the capacity sharing. In Method 3 substation A is

where the PED is planned to be installed unless otherwise indicated.

4.1 SPN selected sites

Method 1:

ID S/S A S/S B

1a.1 523461 - Regent Hill [ T1 ] 523686 - M&S Regent Hill [ T1 ]

1a.2 523693 - M&S Dyke Road [ T1 ] 523686 - M&S Regent Hill [ T1 ]

1a.3 523446 - Frederick Street [ T1 ] 523646 - North Road [ T1 ]

1a.4 523297 - Powis Grove [ T1 ] 523654 - Royal Alexandra Hospital [T1]

Method 2:

ID S/S A S/S B

2.1 523338 - Duke Street [ T1 ] 523653 - Churchill Square East [ T2 ]

2.2 523446 - Frederick Street [ T1 ] 522075 - North Gardens [ T1 ]

2.3 523099 - West Hill Road [ T2 ] 524252 - Buckingham Street [ T1 ]

2.4 523547 - St. Margarets Place [ T2 ] 523623 - Cannon Place [T1]

1 Method 1b involved having a three phase LV circuit breaker at the link box position. Once the supply

of the single phase CBs was resolved this method was no longer required.

FUN-LV SDRC 9.1


Method 3:

ID S/S A and PED location S/S B S/S C

3.1 523637 - Prudential North

Street [ T1 ]

522941 - Vokins [ T1 ] 523230 - New Road [ T1 ]

3.2 522916 - Robert Street [ T1 ] 521244 - Marlborough Place

[ T1 ]

523193 - Gloucester Street

[ T1 ]

3.3 523036 - Church Street [ T2 ] 523259 - King Street [ T1 ] 523615 - Bond Street [ T1 ]

3.4 523025 - Kings Road [T1+T2] 523751 - West Street 77 [ T1] 523173 - Black Lion Street

[ T1 ]

4.2 LPN Radial selected sites

Method 1:

ID Method S/S A S/S B

1.1 1a/c 90813 - Acre Lane 75 (G) 90824 - Acre Lane R/O 88

1.2 1a 90008 - Albert Embankment Camelford

House North (G)

90009 - Albert Embankment Camelford

House South

1.3 1c 90271 - Milkwell Yard 90877 - Coldharbour Lane 39-45

1.6 1c 06586 Cavendish Road 06109 Devonshire Road

Method 2:

ID S/S A S/S B

2.1 90940 - Electric Ave R/O 37 90941 - Electric Lane Ex Supermarket

2.2 67059 - Sutherland Road Brodwick House 67052 - Roman Road R/O Dennis House

2.3 06287 - Morden Road West 06507 - Morden Rd 141

2.4 91045 - Loughborough Park GPO Depot 91043 - Loughborough Park Guinness

Method 3:

ID S/S A S/S B S/S C S/S PED

3.1 07141 - Felsham Rd

124

07863 - Bemish Rd

R/O 28

07132 - Biggs Row

(G)

3.2 30792 - Shirland Rd

Charfield Ct

30759 - Shirland Rd

41

30157 - Amberley Rd

Local

30123 - Ellwood Ct

Shirland Rd

(LV Only)

3.3 06194 - Bushey Rd

East (G)

06602 - The Chase

(G)

06627 - Whatley Ave

(G)

08070 - Bushey Rd

West (LV Only)

FUN-LV SDRC 9.1


3.4 90415 - Fiveways

Guinness Trust (G)

90272 - Minet Rd

Loughborough

School

90325 - Rupert

Gardens (N/A)

90260 -

Loughborough Rd

Newark House

(LV Only)

4.3 LPN interconnected selected sites

Introduction

The simple selection of sites for LPN interconnected system is more problematic as each LV spine

circuit is connected to two or three other substations, which in turn connect via other spine circuits to

more substations.

For simplicity of description for each Method 1 and 2 scheme, a single host substation A is selected

and only those sites that are directly connected by spine circuits from that substation are listed as

Affected Sites. For Method 3 the location of the PED is also given together with its immediate satellite

substations (A, B & C). Radial Embedded Substations (RES) are those not, at present, normally run

connected to interconnected networks. Methods 2 and 3 sites may also include elements of

equipment from Method 1 where RES site are involved.

Method 1:

ID Method S/S A Affected Sites

1.1i 1a 36643 - Pall Mall 80-82 (RES) 31511 - Pall Mall 46-47

34725 - Pall Mall 83 RAC

1.2i 1c 36572 - Portman Cl Opp 21 (RES) 34145 - George St 67-69

LV only (36061)

1.3i 1a/c 34317 - Edgware Rd 112-130 (RES) 30107 - Nutford Pl Holiday Inn

34314 - Edgware Rd 168-176

34300 - Forset St Coopers Stores

1.4i 1c 36714 - Edgware Rd 168-172

Brendon St (RES)

34313 - Edgware Rd 152-166 Brendon St

36026 - Crawford Pl 15-19

34301 - Shouldham St Marylebone Baths

Method 2:

ID S/S A Affected Sites

2.1i 31529 - Piccadilly Ritz Hotel 36300 - Berkeley St 40-50

31550 - Stratton St Stratton Hse

2.2i 36611 - Arlington St Arlington House No2

(RES)

31463 - Arlington St 20 Arlington Hse

31464 - Arlington St 9-10

2.3i 36041 - Duke Of York St 11-14 34673 - Jermyn St Princes Hse

31516 - Piccadilly 177 French Railways

31518 - Piccadilly 203 Simpsons

36540 - Piccadilly 200

34987 - Jermyn St 85-87

2.4i 36785 - Portman Close 26-34 (RES) 34123 - Portman Sq 14 Fitzhardinge Hse

34145 - George St 67-69

34665 - Baker St 18-20

FUN-LV SDRC 9.1


Method 3:

ID S/S A S/S B S/S C

3.1i 24410 - Shaftesbury Ave 125 24409 - Stacey St 31023 - Charing X Rd 82

3.2i 34179 - Bulstrode St Clifton

Ford Hotel

34146 - 9 Thayer St 34174 - Welbeck St 33-35

and

34172 - Westmoreland St

National Heart Hospital

3.3i 30107 - Nutford Place

Holiday Inn (G)

34300 - Forset St Coopers

Stores

34317 - Edgware Rd 112-130

3.4i 34725 - Pall Mall 83 RAC 31511 - Pall Mall 45-47 or

31511 - Pall Mall 100

or

36223 - Pall Mall 36

36643 - Pall Mall 80-82 and

31511 - Pall Mall 45-47

FUN-LV SDRC 9.1


5. Sources of data Pairs of substations and groups of three and their associated networks have been identified by PPA

Energy using:

FUN-LV SDRC 9.1


Appendix A – Guidance Document – Traditional Planning Considerations for Power Electronics Devices Please see the separate document for this appendix.

Appendix B – Selection Criteria and Approach Please see the separate document for this appendix.

Appendix C – DPlan: Support for site selection Please see the separate document for this appendix.