schede asset management services

Load Flow Optimal Power Flow Technical Assessment Financial Assessment Feasibility Studies

BenefitsPrysmian’s cable systems’ know-how provides a globalapproach to the optimisation of a network and to thechoice of the optimal technological solution. UsingPrysmian’s resources and skills from the very beginningequals to relying on a highly qualified professionalteam, capable of proposing the most appropriatesolutions for an optimal network’s exploitation.The feasibility studies feature incorporates thesynthesis of an extensive selection activity of cabletechnologies and types - plus relevant accessories -installation methodologies and - where necessary -monitoring systems. Its main goal is to propose themost appropriate solution for an optimal asset’sexploitation.

ApplicationsOur customers are actual or potential electricalnetworks’ owners/managers, who need optimalsolutions to widen and exploit their existing gridsor to develop new links. The real evolution of the demand for power does notalways match predictions; therefore, some transmission and distribution network’s portionsmay not be exploited properly.The Network Engineering activity provides supportfor a better understanding of a network’s potential.Is a new link really necessary? Which are thebottlenecks? Which are the realistic dispatchingscenarios? What will the medium term networkperformance be?Networks owners and managers frequently need tofind a satisfactory answer to these questions andmore, and the synergy between their networkknowledge and our qualified cable systems experienceprovides the most reliable responses.

Transient in overhead line after generator tripping and following circuit closing

Transient in XLPE cable aftergenerator tripping and following circuit closing

Circuit opening

0.1/MACHINE: PTOV71GG VARIABLE: OMEGA

PU

(1.000, .000)

1.00

1.04

1.06

1.08

.5 1.0 1.5 2.0 2.5 3.0

1.02

0.1/MACHINE: PTOV71GG VARIABLE: OMEGA2/MACHINE: PTOV71GG VARIABLE: OMEGA

PU

(1.000, .000)(1.000, .000)

.99

1.00

1.01

1.02

10. 20. 30. 40. 50.

Z eq1

Z eq3

Z eq27.8 km12.2 km 22.8 km MORATA

4.4 km

41.2 km12.4 km 26.3 km2.5 km

NETWORKEngineering

ASSET MANAGEMENT SERVICES

Network Engineering | Condition Assessment | Monitoring | Emergency

Benefits: > Optimal Solution> Optimal Exploitation

Load Flow Optimal Power Flow Technical Assessment Financial Assessment Feasibility Studies

ReferencesPrysmian guarantees privacy on its customer's strategicactivities, therefore no customer name will be shown inthis area.

ServicesThe Network Engineering activity consists of twophases.First of all, the check of the technical and financialadequacy for the network to meet current and futureneeds. Generally, the network managers themselvescarry out this type of activity.The second phase involves the assessment of the loadconditions and utilization of each single link. Thisknowledge is essential for the optimal exploitation ofa network’s resources and for the development of optimalsolutions.Network analyses, multi-scenario technical studiessupported by dedicated software applications, togetherwith an in-depth knowledge of cable technology arecrucial to fully assess the results and provide tailor-made optimal solutions.Steady-state, short circuit and transient stabilityanalyses carried out by means of PTI - Load Flow® andEM transient analyses - opening/closing, lightning - bymeans of ATP - EMTP® represent load and power flowstudies application examples.The technical and financial assessment phases are -instead - developed, through probabilistic risk analysisapproaches.

Transient recovery voltage aftercircuit opening

0.306 0.308 0.310 0.312 0.314 0.316 0.318 0.320 0.322[s]-400

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NETWORKEngineering



Benefits: > Optimal Solution> Optimal Exploitation

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Prysmian Cavi e Sistemi Energia srlViale Sarca 222, 20126 Milano, Italy - tel. +39 02 6449 1, fax +39 02 6449 2931www.prysmian.com - [email protected]

After-Installation TestsPeriodical ChecksInspections on Ancillary SystemsDefects-Related RiskSample TestsSystem Inventory

BenefitsThe execution of this type of tests, especially ifcombined with Partial Discharges measurements (seedatasheet), provides three main benefits: optimal linkexploitation, higher reliability of the tested system andreduced number of unplanned interruptions.A successful outcome of these tests is a guarantee forthe correct execution of the laying and installationoperations, as well as for the absence of damages dueto the transport and handling of cables and accessories.Additional and more accurate information can beobtained by carrying out these tests alongside withPartial Discharges measurements (for more details seethe related datasheet).

ApplicationsThe Condition Assessment services include all ofthose activities aimed at defining the conditions ofall the components of a link before it is put inservice and during its interruptions, be themplanned or unplanned.More specifically, After-Installation Tests consistof mandatory checks thoroughly regulated byinternational standards such as, for instance IEC60502, 60840 and 62067, respectively for MV,HV and EHV, and apply to new installations. Inpractice, these tests are requested by linksowners/managers also after repair interventions tocheck the correct execution of the interventionitself.With the development of new methodologies andtechnologies, Partial Discharges tests are nowcoming alongside with the tests prescribed and/orsuggested by the standards.

For more details see the related Monitoring: PartialDischarges datasheet.

Mobile test-set ready for operation 440 kV Mobile Unit

CONDITIONAssessment



Benefits: > Optimal Exploitation> Increased Reliability> Reduced Unplanned Outages Time

150 kV Mobile Units

ReferencesCORUS The Netherlands DELTA The Netherlands Deltius The Netherlands DOW The Netherlands East Midlands Electricity UKEndesa Spain ENECO The NetherlandsENEL ItalyIberdrola Spain Jersey Electric Company U.K.National Grid Transco U.K.NUON The NetherlandsScottish Power UKScottish & Southern Energy UKSHELL The Netherlands Thermophos International The Netherlands TZH The Netherlands Union Fenosa SpainWPD UK

ServicesAs already mentioned, After-Installation Tests arethoroughly disciplined by international standards, aswell as their execution procedures. As for the tests on the insulating layers, theowner/manager of the link is generally left the choiceof choosing between an AC and a DC test, even thoughthe DC test is strongly discouraged.The tests are carried out by applying a voltage to therelevant link. The applied voltage depends on thecable’s class and on the applicable standard.Generally, both for technical and for security reasonsthe voltage is applied to the link by means of mobilegenerators. Prysmian owns the largest fleet of mobile variablefrequency voltage generators, and is capable of testing400 kV cable systems over a length of approximately14 km.

The Test-Set Fleet Capability

Max Voltage(kV)

Max Load(F)

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CONDITIONAssessment





55 kV Mobile Unit

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BenefitsA program of periodical checks ensures a thorough andup-to-date knowledge of a system’s conditions.The early identification of possible deviations from thestandard conditions allows the planning of correctioninterventions aimed at increasing the system’s reliabilityand, therefore, at reducing - if not eliminating - extra costdue to restoring interventions under emergency conditions.Furthermore, the ability of associating risks to possibledeviations from the standard - based, mostly, on anextensive experience related to cable systems - canoffer, among other things, two main benefits: a morein-depth focus of the maintenance program and therapid elimination of the problem itself.Should partial discharges be detected within the system,for example, the possibility of tracking a discharge’sprimary cause, starting from the discharge itself (seePD datasheet) allows to assess whether an immediateintervention is necessary or actions can be delayed, forinstance, by operating a circuit at a reduced load.Final decisions, including possible and unplannedinterruptions of the service, are, of course, up to thecustomer. Similar circumstances may occur also in thecase of inspections to oil pumping stations or othercomponents other than cables and accessories.

ApplicationsEven though most of the power transmission anddistribution cable links can be considered as freeof maintenance, periodical checks of the multifariouscomponents of a system ensure an enhancedreliability of the system itself, as a whole.Regardless of a link’s technology, a detailedprogram of periodical checks of both cables andaccessories and systems’ components - as, forinstance, oil pumping stations - can always beplanned.The identification of possible deviations from thelink’s design conditions can naturally lead to theassessment and analysis of the risk, if any, associatedto the deviation itself.Such analysis can prove to be an effective support forthe planning of the subsequent maintenance activities.

I.R. Investigation

CONDITIONAssessment



Benefits: > Increased Reliability> Reduced Unplanned Outages Time

Mobile unit for on-site oil analysis


ServicesPrysmian suggests to its customers a tailor-made program of periodical checks of the various componentsof a system, on the basis of the type of asset theyown/manage.Checks can either be electrical - e.g.: oversheathintegrity check, partial discharges measurement, etc. -or visual/mechanical, such as, for instance, oil-filledterminations pressure gauges functioning, surgevoltage limiters integrity or any other necessary checkfor the correct operation of a system.Basically, it is a set of tailor-made control programsbased on the activities described in the variousMonitoring and Condition Assessment data sheets.Upon completion of the control activities, the risks (ifany) associated to the deviations from the standardconditions are assessed and the results can betranslated into a system’s classification, which rangesfrom “Excellent Conditions” to “End of Service Life”.The customer, with the support provided by Pirelli, willthen assess whether to integrate the maintenanceplanning activity with the collected information toguarantee an acceptable level of reliability of thesystem and, at the same time, minimise the costgenerated by maintenance/restoring activities.


CONDITIONAssessment



Test set-up for oil analysis

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BenefitsA complete and detailed inventory of a networkrepresents the starting point of an effective andappropriate management of a system.The availability and traceability of the informationrelated to the building of and interventions on anetwork’s circuits are an essential assumption for anefficient maintenance planning process and an effectivepolicy of minimisation of the restoring timeframesafter unplanned events.The execution of a system’s inventory allows a quickidentification of the cables and accessories types aswell as an emergencies’ cross-reference and anassured knowledge of the cable’s history (installation,tests, emergencies, etc.).The sample tests carried out on cables’ sample lengthscoming from interventions on the network (e.g.diversions) provide, instead, useful information aboutthe conditions of the origin circuit and, sometimes, ofcircuits alike by composition, environmental andoperating conditions.The main advantage comes from the possibility ofcollecting information by submitting the cables to tests- destructive tests, in some cases - which could not becarried out on operating cables, to fine-tune a cable’sperformance prediction.

ApplicationsThe Condition Assessment services include all ofthose activities aimed at defining the conditions ofall the components of a link before it is put inservice, and during its interruptions, be themplanned or unplanned.More specifically, the activities described in thisdatasheet can be applied to existing installationsand are aimed at collecting information for a morein-depth knowledge of the network’s structureand conditions, and to reduce, accordingly, theinterventions’ timeframes in the case of serviceinterruptions.The System Inventory activity allows reorganisingthe knowledge possessed about a network, whichmay be “dispersed” among the constructor, theinstaller and the owner.The collected information will prove highly valuablemainly in the case of maintenance or emergencyinterventions planning.Sample Tests include checks which can be carriedout on operating circuits “sample lengths” comingfrom rerouting or dismissal works.

Laboratory for electrical tests

CONDITIONAssessment






ServicesThe execution of a network’s inventory requires astrong interaction with the customer.Its main sources are Prysmian’s design and installationarchives together with the network owner’s.The information is gathered and organised into adatabase for an optimised and faster data browsing.Regardless of the underlying reason, in the case ofmissing data, network’s inspections can be carried outto bridge as much as possible any lack of informationfollowing an accidental event. There is no standard sample test procedure, since theylargely depend on the sample lengths’ dimensions andconditions.In general, cables’ sample lengths should be preferablysubject to all electrical, mechanical, chemical andphysical tests, which may provide information regardingperformance expectations.Appropriate devices can extrapolate the informationcollected, as for operating circuits alike, which, forobvious reasons, cannot undergo intrusive tests.


CONDITIONAssessment


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Partial DischargesPower FactorCable TemperatureLoadWater Penetration

BenefitsThe Power Factor and PD Monitoring services representthe best existing tool for the almost continuous analysisof HV and EHV cables’ insulation conditions.This type of measurements allows to carry out - bothgenerally and locally - an almost real-time assessmentof a cable’s conditions, and provides the network’sowner/manager with a reliable feedback regardingpossible changes in such conditions, so as to reschedule,if necessary, ordinary maintenance programmes, loadplans and any other element, which may speed up theevolution of specific ageing processes.The monitoring of these phenomena or their periodicallyrecurrent measurement increases the reliability of thelink undergoing the test and provides a well-definedstatus of its conditions. It also allows taking into account the opportunity ofoperating the link with reduced loads, instead ofexcluding it before its time from the network forpreventative maintenance interventions that couldinstead be delayed, thus minimising costs.

ApplicationsPower Factor (tand) and Partial Discharges (PD)are - apart from the voltage withstand test, whichcould be destructive - among the most reliableindicators of a cable’s conditions. They can beapplied to all cable technologies. The Power Factor measurement provides clearindications about the trend of the link’s insulatinglayer average conditions; the PD measurementallows locating, identifying and, in the case inpoint, classifying the localised fault.Even though PD measurements on installed cablesystems (be them old or new installations) are notyet disciplined by any national or internationalstandardisation body, the importance of this typeof test - carried out either after the installationtest operations or with assessment purposes or,still, for a system’s life conditions monitoring - iswidely acknowledged.The above-mentioned characteristics together withthe possibility of providing PD’s risk estimatesmake this test an essential tool for the optimalexploitation of a system, for the planning of maintenance interventions and, accordingly, for anincreased reliability of the link undergoing the test.

Termination Test Setup

MONITORINGASSET MANAGEMENT SERVICES



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Wide range Sensors

ReferencesCLP Hong Kong DELTA The Netherlands EdF France Endesa Spain EPTE BrazilMEAG GermanyNational Grid Transco UKR.E.E. SpainScottish Power UK

ServicesThe Partial Discharges measurement can be carried outboth on-line and off-line.The hardware and the software used by Prysmiancapture the PD signal through suitable sensors and bymeans of a dedicated acquisition system.The signal is then analysed with a fuzzy-logic-basedsoftware, which allows locating the PDs, identifyingtheir origin and, in case, classifying them.A database is continuously updated and referred to,for the classification of the different discharge signals.The use of PD sensor pre-equipped accessories ishighly recommended for HV and EHV links, so as toallow on-line monitoring with a considerable reductionin the measurement timing.The offered system is capable of separating - notFILTERING - noise and disturbances from the signalitself, thus increasing the measurement’s reliability andexcluding the risk of filtering possible dischargeslocated in the noise or in the disturbances’ band.Prysmian can supply a wide range of configurations,which allow performing Partial Discharges measurementson practically any type of link, in any operating conditions(in service, during maintenance periods, etc.), alsothanks to the support of an impressive fleet of mobileresonant generators at variable frequency rangingfrom 20 to 300 Hz (see After-Installation Testsdatasheet) and achieving outcomes, which in somecases - given the purity of the signal - can be compared to laboratory measurements.

MONITORING

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PD pattern relevant to acquisition in a MV cable with an artificial defect, before (A) andafter (B) electrical tree inception. Test voltage 18 kV, room temperature.

8.00E-1

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PD Pattern and Classification

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BenefitsThe main benefits deriving from the use of this RealTime Thermal Rating (also RTTR) system known asOPTOPOWER® can be summarised as follows:

> transfer of the maximum transmittable power withno cable’s thermal overload;

> hot spots location;identification of the soil’s thermal characteristicsduring service operations;

> prediction of the temperature profile in the case ofpower overload;

> power overload under controlled conditions (e.g.emergency conditions).

OPTOPOWER® provides also a better understanding ofthe entire system’s load and of the real operating con-ditions, to improve the system’s reliability and financialreturn. It also provides useful information for futurecable systems’ specifications.



Benefits: > Optimal Exploitation> Increased Reliability

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Example of screenshot

ApplicationsThe real environmental operating conditions of acable are generally less critical than those providedfor in its design. Therefore, when in service, a cablecan have operating margins, which may vary over time.These margins depend on the power load the cableis subject to, on the mutable environmental conditions(e.g. soil humidity and thermal conductivity), on thevariation of its surroundings - new installations, etc...The possibility of precisely and safely knowing,and, therefore, exploiting such operating marginsrepresents, in deed, a valid tool to optimise asystem’s economy - by fully leveraging, forinstance, its transmission capabilities yet operatingunder safe conditions - and to increase its reliability- by locating possible hot spots and, for example,operating under controlled overload conditions.The proposed system can be applied to both newlyinstalled and existing circuits.In the case of new circuits, cables and accessoriescan either be equipped with a built-in optical sensoror with a pre-installed small pipe in which the sensoris “blown” after the installation (this solution is notapplicable to all cable types); else, the sensor canbe placed close to the circuit. This latter can be, asan example, an applicable solution to retrofitexisting circuits.

CENTRAL CONTROL UNIT

FIELD UNITS AND SENSORS ON THE CIRCUITS

REMOTE CONNECTIONS

Extruded cable with embedded Distributed Temperature Sensor;System Architecture.


ServicesThe system is based both on the continuous measurementof temperature and loads, and on subsystems such ason-board databases and dedicated mathematical models.The temperature is measured by means of commerciallyavailable systems, either by means of an optical fibreas distributed sensor or with quasi distributed orpunctual sensors. The sensors can be either built-inwithin the cable or placed close to the assets to be managed.The current is measured independently or obtained inreal time through the customer’s interface, by meansof hardware, which is commonly available in manytransmission plants.The mathematical model’s calculations are based on IEC60853 and IEC 62087 standards, additionally improved tofully exploit in real time the measurements scope and, in general, to enable the thorough management of the cable’ssystem, with an ideal and safe thermal load of the cable itself.As a rule, the possible overload of a link at a certainpoint in time depends on the current conditions and is,then, given as constant over a certain period of time.OPTOPOWER® can instead evaluate the admissibleoverloads, which are continuously calculated takinginto account not only the current conditions but alsothe ongoing thermal transients of the link and thethermo-dynamical characteristics of the link’s elements. In the same way, the environmental thermal characteristicsvariations (e.g. soil drying rate) are continuously revaluatedand their effects on the ampacity capabilities are takeninto account to update, modify and correct in real timethe system’s forecasts. The system, therefore, can calculatein real time: conductor’s temperature, permitted currentin stable conditions, possible power overloads (both inthe short and in the long term), evolution of the thermaltransient and heat dissipation and future overheatingof a link’s elements.

MONITORING

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Benefits: > Optimal Exploitation> Increased Reliability




BenefitsWith a reduced financial investment a cable can beequipped with the WPM device.One of the main advantages of this equipment is theability of continuously monitoring the possible penetrationof water through the metallic sheath, also - and aboveall - when the cable is operating.The monitoring activities, therefore, do not requireservice interruptions.This represents a benefit for the end users and a savingopportunity for the link’s owner/manager.Thanks to this system, which can detect the possiblepenetration of even small quantities of water in a veryshort time, the cable’s outer sheath routine tests (HVtests) are no longer necessary.The sensors’ sensitivity and the data capturing systemensure a highly precise location of the fault.This system allows detecting also possible damagescaused to the outer sheath by an external event (e.g.civil works) as the event itself is still going on, thusmaking the identification of possible responsibilities easier.




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High accuracy in water penetration location

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Accuracy of fault location

Water Monitoring of XLPE HV Cables

ApplicationsThis monitoring system provides maximum reliabilityif applied to cables with welded metallic sheath.In the long run, water can damage the insulatinglayer; therefore, there must be no trace of moistureinside the cable.In addition, it is not infrequent that externalevents could damage the cable’s outer sheath, andbecause of these potential risks, the various links’owners/managers periodically carry out HV teststo check the outer sheath’s integrity.The use of a monitoring system such as WPM forthe relevant class of cables allows both increasingthe cable’s reliability and reducing the number ofroutine interventions on the cable itself (HV outersheath routine tests, in the case in point).

Extruded cable with embedded WPM sensor

Water Penetration fast detection and location

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ServicesThe WPM device is usually made of two sensors (oneoperating and one spare) for each cable, lapped ontothe cable itself over its entire length in-between thescreen wires, and of a monitoring piece of equipmentthat measures uninterruptedly the sensors’ resistance.The penetration of water through the welded metallicsheath determines the sensors’ resistance variation.The monitoring system detects this variation and,consequently, activates the warning signal and thepossible interventions agreed upon with the customer, if any.Meanwhile, the equipment provides also the location ofthe damage and displays its position on the screen ofthe data capturing tool.

MONITORING

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Partial DischargesPower FactorCable TemperatureLoadWater Penetration Benefits: > Increased Reliability

> Reduced Unplanned Outages Time

Cont

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Measuringdevice

Linkbox

LinkboxHV cable system

water sensor

cable screen

System architecture Example of link-box for WPM



24h/7d AvailabilityFault LocationRepairEmergency CapsSpare Parts Stock

BenefitsAn unexpected or, in any case, an unplanned eventsuch as a fault on a transmission or on a distributionline can have a strong economic impact.Suffice it to think that in some cases in Europe a link’sfailure could reach an average cost of approximately0,50 € per V.This means that the estimated cost of a failure on a150 kV line could be approximately 75.000,00 €.In addition, also the losses due to the unsold powerand the cost of users’ refunds must be taken intoaccount.The emergency service includes, among other things,the optimal storage of spare parts (accessories, cablelengths...).The agreement of such a service ensures, therefore,the minimisation of costs due to unplanned serviceinterruptions.

EMERGENCYASSET MANAGEMENT SERVICES


Benefits: > Reduced Unplanned Outages Time

ApplicationsAll circuits, be them for transmission or fordistribution purposes, can be subject to unplannedservice interruptions.Generally, the origin lies in civil works carried outin proximity to the circuit itself (for example,excavations near buried circuits) or in regularactivities, which sporadically “invade” the circuit’sprotected area (submarine cables damaged byanchors).These and all of the other cases of unexpectedservice interruption require a rapid and professionalintervention to minimise the economic damages toboth the circuit’s owner/manager and the community.This service allows relying on a team ready tointervene on any type of circuit (either terrestrialor submarine) at any voltage.The intervention’s procedure and timing are agreedupon directly with the customer and may varyaccording to the various circuits’ position, yet theyalways ensure an excellent contingency management.

Emergency splice

ReferencesAquila UKCORUS The Netherlands DELTA The NetherlandsDOW The NetherlandsEast Midlands Electricity UKEDF Energy UKEndesa SpainENECO The Netherlandse.ON The NetherlandsESSENT The NetherlandsHydro Agri The NetherlandsIberdrola SpainJersey Electric Company UKNational Grid Transco UKNEDL UKNorthern Ireland Electricity U.K.NUON The NetherlandsScottish Power UKScottish & Southern Energy UKThermophos International The NetherlandsTZH The NetherlandsUnion Fenosa SpainUnited Utilities UKWPD UK

ServicesPrysmian can guarantee a global assistance service tothose customers who stipulate an emergency servicecontract.Thanks to an extensive presence on the territory,maximum intervention times in the case of failure and24-hour availability can be guaranteed.The service includes fault location, first emergencyinterventions such as oil discharge control and finalrepair interventions.An increased quality of the service quality is alsoensured by the possibility of storing in a controlledenvironment of spare parts such as terminations,joints and/or cable lengths.This solution, highly recommended for particularlycritical links, allows repair interventions in an extremelyshort time.Before the link it is put back in service after itsrestoration, the execution of a tests’ set is highlyrecommended (see After Installation Tests; PartialDischarges datasheets).

EMERGENCY


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Mobile Unit for Emergency Interventions


24h/7d AvailabilityFault LocationRepairEmergency CapsSpare Parts Stock


Benefits: > Reduced Unplanned Outages Time

schede asset management services

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optimal networks exploitation

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