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Technical Data on powerPerfector and powerPerfector Plus

Commercial in confidence powerPerfector Technical Data Outline Contents

Contents

Section Title Page number

1 powerPerfector – Voltage Power Optimisation (VPO)® 1

1.1 Generic Specification 1

1.2 Schematic and Explanation 2

1.3 Reliability and Efficiency 4

1.4 powerPerfector Plus 5

1.5 Unit Sizes 6

1.6 Testing and verification 7

2 Secondary Benefits 9

2.1 Transient Protection 9

2.2 Reduction in reactive power (kVAr) / improved power factor 10

2.3 Lower harmonic distortion 11

2.4 Improved phase voltage balance 12

3 Further Benefits 13

3.1 Reduced maintenance burden 13

3.2 Business Continuity 13

3.3 Increased capacity on breakers and lower kVA charges 13

3.4 Improved HV transformer efficiency 14

powerPerfector Technical Data OutlineCommercial in confidence 1

1. powerPerfector - Voltage Power OptimisationpowerPerfector have created a unit that is specifically intended for integration into a building’s power supply at source. The amount of copper presented to the circuit is minimal, ensuring that efficiency is very high and the unwelcome effects of high impedance are avoided, while Voltage Power Optimisation (VPO) is carried out through magnetic interactions without recourse to active (mechanical or electronic) components, mitigating failure. The power quality improvements delivered by the unit are woven in to the design in a way that would not be possible had we designed the unit using a conventional transformer or an autotransformer as the platform technology. There is no requirement for constant online monitoring, a bypass or a heat sensor with a powerPerfector unit as it has been designed to become a permanent part of the supply infrastructure. The design, materials and build quality to achieve the robustness required of an installation at the crucial point in the circuit where it sits.

1.1. Generic Specification

Generic Name High-power voltage power optimiser with embedded condenser winding for harmonic mitigation, unreferenced secondary star point for passive phase voltage balancing.

Construction High purity cold-wound copper sheeting, low-inertia flaked silicon-steel core. Dry type.

Phases Three phase (3 wire); no neutral connection required

Input (Primary) Voltage 400V +/- 10% (UK statutory voltage range BS EN 50160:2007)

Input Frequency 50/60 Hz

Output Voltage powerPerfector Standard - bespoke optimisation settings for each unit to reach site’s optimal voltage of 220V single phase at the far point. Each unit has four optimisation settings as well as 0%.

Output Frequency As input

Peak Efficiency Up to 99.94%

Insulation Resistance IEC 726 Class H (180°C)

Display powerPerfector Standard - LCD display; (L-L) input / output voltage.

Typical energy savings 6 – 20%

Typical reduction in reactive power ~30%

Voltage Transient Protection Protection against most common transients

Phase voltage balancing Through differential compound interaction

Harmonic mitigation Passive low filtration from primary winding, plus tertiary delta winding to mitigate 3rd, 5th and 7th harmonics (No tuned circuits, active or electronic components, so no point of failure). Triplen harmonic reduction through phase balancing.

Overload Ability 110% for 3 hours

150% for 1 hour

Cooling Natural air flow

Size Bespoke and site specific

Failure rate ZERO

Maintenance requirement 5-yearly routine wiring checks. No other maintenance is necessary.


1.2. Schematic and ExplanationThe powerPerfector unit has been specifically designed to reduce energy consumption and improve power quality at the source of a supply to a building or site. We have used a unique combination of magnetic interactions to achieve efficient voltage optimisation and improvements in power quality that reduce energy use and improve the robustness of the power supply. Figure 1 below describes the technology in the form of a line diagram.

Figure 1 – powerPerfector Schematic Representation

Average energy saving 11% average savings from post installation analysis reports.

Testing and verification (Certificates and results can be provided on request)

• CE marked

• Complies with BS EN 60076-11:2004

• Power quality and electrical type testing (NaREC (UK))

• Japanese (CB) accreditation

• NATA (Australian and S.E. Asian) accreditation

• ASTA tested by a UKAS laboratory

• Short circuit withstand tested

Recyclability ~98% of the volume of the materials can be recycled

Warranty • powerPerfector – Voltage Power Optimiser – 15 Years

• powerPerfector Plus – Voltage Power Optimiser – 15 Years

• powerPerfector Plus – AVC control unit – 3 Years

Expected Lifecycle ~50 years

Primary windingfew turns of high purity copper

Secondary windingOptimisation settings

V out(220V)

Tertiary windingharmonic mitigation

Unreferenced star pointphase balancing

V in(240V)

L1

L2

L3

(i)

(ii)


Figure 2 – powerPerfector unit (unenclosed)

Figure 2 explains the electrical schematic presented in Figure 1 using a picture of the physical unit, pointing out all three windings on each phase and the connections between them. Labels A and B show the input and output terminals to the primary winding (Pr) respectively on one phase. These terminals connect the unit in series into the supply infrastructure. Label C shows the optimisation setting selection and connection of the Sstar winding mirrored in Figure 1 on the previous page. The fact that these cables are of lower rating than the overall unit visually demonstrates that the full load current only passes through the primary winding. The Sstar windings form their unreferenced star point (as described previously) at the rear of the unit. Label D (to the rear of unit, hidden from view) indicates the location of the terminals that connect the Sdelta to form a closed loop on each phase. All three windings per phase are all tightly wound around a flaked silicon steel core and insulated using cast resin.

Primary Winding

(‘Pr’)

This winding is in series with the site’s power supply and carries the load current on each phase. It is constructed from heavy-gauge copper sheets, with very few turns, meaning that the unit has very low impedance and very low losses. This winding acts to filter harmonics and protects the site from common transient events.

Secondary Winding

(‘Sstar’)

The interaction between the primary and secondary winding on each phase acts to reduce the voltage by a fixed percentage. For example, if Vin is around 240V, Vout will be 220.8V, assuming an 8% optimisation setting. Each powerPerfector unit has four optimisation settings as well as a 0% setting.

An example of a typical optimisation setting range is -5%, -6%, -7%, -8% and a 0%.

The connection between each phase has a current flowing that is in direct proportion to the difference between the three phase voltages. This connection forms an unreferenced star point (ii) on the secondary side. In this way, the powerPerfector is able to compensate for imbalanced phase voltages without recourse to active (electronic or mechanical) components.

Tertiary Winding

(‘Sdelta’)

These are connected as a closed ‘delta’ configuration. The purpose of the closed loop is to provide a path to circulate and dissipate harmonic currents present on the incoming supply, thus attenuating and preventing them from circulating into the downstream load. This winding has the same effect on harmonic currents that are generated downstream of the powerPerfector unit, preventing harmonic currents that are generated on site from circulating into the upstream load.

BA

C

D


1.3. Reliability and EfficiencyThe powerPerfector has been designed with no moving parts or electronics: voltage optimisation and power quality improvement is achieved through the interaction of magnetic fields only, and the unit is as reliable as the incoming power supply itself. Since 1993 over 180,000 powerPerfector units have been installed worldwide, without a single failure. The unit requires no maintenance and the anticipated life-time expectancy is 50 years.

The powerPerfector unit has been engineered to exacting Japanese standards and each unit is hand made in the UK. The insulation used is class H and if over current protective devices fail to operate, the powerPerfector technology can withstand a 50% overload for 1 hour. Both points further demonstrate the resilience of the technology.

The high efficiency of the design means there is negligible heat loss with no requirement for temperature sensing or forced cooling. As a result the unit sustains very little degradation over its lifetime and performance is not affected.

The efficiency of the powerPerfector is supported through the purity and processing of the copper windings. The primary winding is constructed from wide, cold rolled copper sheet rather than wire and the space around the coils is reduced as far as possible to minimise wasteful heat. Also essential to efficiency is the response of the core to an alternating magnetic field - the powerPerfector core is constructed from low inertia flaked silicon steel with a hysteresis loop close to 90°.

Innovations in the design and manufacturing processes have allowed the powerPerfector unit to achieve efficiencies of up to 99.94%.

High Conductivity Copper SheetA major innovation in the fabrication of powerPerfector units is the use of high purity cold-rolled copper sheet, rather than lower grade copper wire or strips used in conventional transformers, for example. This significantly reduces wasteful heat, improving efficiency.

In the manufacture of dry type inductive devices, efficiency comes from having a very ‘tight’ construction. Any gaps between windings, or between windings and core, can cause a build-up of heat in ‘hot spots’ that can become dangerous.

As the powerPerfector is designed for maximum efficiency and total reliability, minimisation of gaps is central to its design and manufacture throughout. Innovative winding techniques and unique cold-rolled copper sheeting are used in the manufacturing process, with each unit being hand-wound by a specialist winding engineer. Quality control is subject to exacting Japanese standards.

The low number of turns required in the design of the powerPerfector primary winding ensures that the amount of copper presented to the circuit is minimal, keeping the efficiency high and the impedance negligibly low. No one unit has an impedance of greater than 0.5%.

Flaked Silicon SteelThe use of flaked silicon steel allows the magnetic core to have low inertia which is crucial to the efficient operation of the device, and ensures that the powerPerfector unit can achieve an efficiency of 99.9%

Cast Resin Insulation (Class H)powerPerfector units use Insulation Class H (180 degrees C), which is above the UK standard class F (155 degrees C) for cast resin devices. This is in recognition of the critical point in the circuit that powerPerfector technology sits. A breakdown of the insulation on a device would lead to short circuits, which would mean operational failure and the possibility of a fire, and hence the quality of the materials and manufacturing are key.


The powerPerfector Plus unit is based on the standard powerPerfector technology, achieving the same benefits and reliability. At the same time, however, it also adds the benefits of dynamic voltage control. A thyristor based Automatic Voltage Controller (AVC) is connected in parallel and selects the optimisation settings on the powerPerfector unit in response to the incoming voltage, giving an output in a fixed band no lower than a user defined minimum (374 – 392V) when in automatic mode. This can be adjusted while the unit is online, and these settings can be selected both automatically and manually. An example of the powerPerfector Plus in operation is shown in Figure 4 – the red line gives the input voltage profile from the mains supply and the green line shows the output of the powerPerfector Plus.

Figure 4 – powerPerfector Plus example voltage profile

1.4. powerPerfector PlusThe powerPerfector Plus is a specialist technology that is recommended when the electrical supply is volatile and unstable and accounts for around 5-10% of our total sales.

Automatic Voltage Controller (AVC)

Voltage Power OptimiserpowerPerfector

21/04/09 22/04/09 24/04/09 26/04/0923/04/09 25/04/09 27/04/09200

210

220

230

240

250

260

Volts

Minimum supply voltage, 207V (BS EN 50160:2007)

Present Voltage

Optimised Voltage


The thyristor technology used in the powerPerfector Plus AVC is extremely reliable and customers can enjoy the benefits without any risk to the integrity of their supply. In the unlikely event of a failure there will be no interruption to power supply as the AVC is connected in parallel with the voltage optimiser itself, allowing it to be ‘hot swapped’. The module is disconnected, leaving the voltage at a 0% optimisation whilst allowing the site to benefit from all the other features of a powerPerfector Plus unit. The problem can then be corrected and the module replaced and brought back online without shutting down the power at any point. If a BMS terminal is available within the switch room the powerPerfector AVC can be connected and remotely register if there has been a failure in the module and it has reverted to 0% optimisation.

1.5. Unit SizespowerPerfector technology is available in a range of sizes that can be selected according to your site’s specific power demands. As the design uniquely affords consistently high efficiency across the load range there is no disadvantage in oversizing a unit to allow for future expansion.

Voltage Optimisation Settings

powerPerfectorAll powerPerfector units have four voltage optimisation setting options in 1% increments ranging between -3% and -12%, allowing accurate optimisation and flexibility should there be a change in local conditions. All units include an additional 0% setting.

powerPerfector PlusAll powerPerfector Plus units are equipped with five voltage optimisation settings available that are automatically selected by the Automatic Voltage Controller (AVC). Settings are in equal increments with three minus settings and one “boost” setting, able to raise the mains voltage if it drops below the optimum range.

*Bespoke unit sizes are available on request.

EnclosurespowerPerfector units are supplied with an IP31 rated enclosure for indoor use allowing natural ventilation of the unit. IP43 rated enclosures are available for outdoor use. Our panel manufacturers are able to design specialist shaped enclosures to fit tight areas and meet any specific colour requirements.

Both powerPerfector and powerPerfector Plus units are available in the sizes shown in the table overleaf, which also provides dimensions. It should also be noted that bespoke unit sizes can be manufactured on request.

+1.5, 0, -1.5, -3, -4.5% – Up to 2000kVA

+2, 0, -2, -4, -6% – Up to 1500kVA

+2.5, 0, -2.5, -5, -7.5% – Up to 1500kVA

+2.7, 0, -2.7, -5.4, -8.1% – Up to 1000kVA

+3, 0, -3, -6, -9% – Up to 1000kVA

+4, 0, -4, -8, -12% – Up to 1000kVA

Optimisation settings (%)-12-11-10-4 -9 -8-7-6-5-3-210+1+2+3+4


Table 1 – powerPerfector / powerPerfector Plus unit size range

1.6. Testing and verificationThe following lists the testing and verification of powerPerfector technology and full details are available upon request.

• NewandRenewableEnergyCentre(NaREC),UK • Type Testing • Power quality testing • Short circuit withstand testing

• UniversityofNottingham • Energy saving / performance testing (lab)

• EATechnology

• EEVSInsightLimited • Energysaving/performancetesting(field)

• SPI/NATA(Australia)typetesting

• JET(Japan)typetesting

• TÜVSÜD(Japan)typetesting

• Shortcircuitwithstandstesting

KeyStandard:BSEN60076-11:2004

Rating kVA/Amperes (powerPerfector)

Height (mm)

Width (mm)

Depth (mm)

Weight (approx kg)

pP70kVA / 100A 555 500 455 125pP110kVA / 160A 795 640 555 200pP175kVA / 250A 795 640 555 265pP220kVA / 315A 885 630 675 280pP280kVA / 400A 875 640 665 315pP440kVA / 630A 1115 660 705 500pP560kVA / 800A 1215 730 725 565pP690kVA / 1000A 1415 880 835 605pP830kVA / 1200A 1615 1060 905 760pP1000kVA / 1450A 1615 1060 905 875pP1250kVA / 1800A 1615 1110 990 1350pP1500kVA / 2150A 1615 1110 990 1100pP1750kVA / 2500A 2115 1860 1270 1250

pP2000kVA / 2900A 2115 1860 1270 1480

Rating kVA/Amperes (powerPerfector Plus)

Height (mm)

Width (mm)

Depth (mm)

Weight (approx kg)

PPP‐30kVA / 45A 1075 900 430 125PPP‐50kVA / 70A 1075 900 430 150PPP‐70kVA / 100A 1075 900 430 225PPP‐105kVA / 150A 1375 1200 600 295PPP‐150kVA / 220A 1375 1200 600 325PPP‐210kVA / 300A 1375 1200 600 392PPP‐280kVA / 400A 1375 1200 600 475PPP‐350kVA / 500A 1375 1300 650 530PPP‐420kVA / 600A 1375 1300 650 590PPP‐520kVA / 740A 1500 1400 750 590PPP‐560kVA / 800A 1500 1400 750 696PPP‐650kVA / 930A 1600 1500 750 696PPP‐740kVA / 1050A 1600 1500 750 802PPP‐830kVA / 1200A 1875 1750 850 920PPP‐1000kVA / 1450A 1875 1750 850 1003PPP‐1250kVA / 1800A 1875 1750 850 1170PPP‐1500kVA / 2150A 1875 1750 850 1270PPP‐1750kVA / 2500A 1975 1800 950 1420PPP‐2000kVA / 2900A 1975 1800 950 1570

powerPerfector Plus product rangepowerPerfector product range

Evaluated


1.6.1.NaRECThe power quality benefits of the powerPerfector were tested by NaREC in 2008/09. This provides independent confirmation that the powerPerfector has an intrinsic ability to reduce levels of harmonics, without the need for any bolt‐on components such as filters or zig‐zag transformers. The tests also demonstrated the unit’s ability to act as a soft‐start, and to reduce real and reactive power use in induction motors. The lead testing engineer can be contacted upon request as a reference. We would like to draw attention to the following extracts from the original reports, which prove that the powerPerfector is able to filter harmonics, and does not contribute any harmonics to the supply.

...“It can be concluded that the powerPerfector doesn’t contribute any additional harmonic content to the source.”

...“For all conditions as tested… the effect of monitoring harmonic distortion on the source & load sides, with a 30kVA powerPerfector unit in circuit was to decrease the amount of current harmonic distortion.”

1.6.2. EA TechnologyThe first powerPerfector unit in the UK was tested by EA Technology (the former R&D centre for the UK’s power industry) in 2000/2001 on behalf of powerPerfector Ltd. The unit was installed at a Tesco store in Cleveleys, and the testing engineer was Russell Benstead. The complete report can be made available upon request, but we would like to draw attention to the following extracts:

. . . “The powerPerfector provided very significant energy savings at the Cleveleys site.”

. . . “Whilst EA Technology have come across autotransformers for energy saving, the low losses and additional features make the powerPerfector unit unique, as far as we are aware.”

Certificates or reports for all testing and verification can be provided upon request.


2. Secondary BenefitsElectrical equipment that has a poor quality power supply will operate with reduced efficiency, causing energy to be wasted, and electricity bills to be higher than necessary. In the UK, the power quality parameters within which electricity must be supplied to a site are defined by BS EN 50160:2007, but it is widely accepted electricity supplied to commercial and industrial sites is of deteriorating quality and generally at a voltage that is higher than the ideal level for most electrical devices.

Significant energy savings can therefore be achieved by optimising the power supply at source to correct common power quality problems, allowing the entire electrical load to run at high efficiency. This means that a powerPerfector will deliver high energy savings and will additionally protect the site against harmful distortion of the power supply.

Over and above voltage optimisation the powerPerfector achieves the following power quality improvements:

• Protectionfromcommonvoltagetransients

• Reductionsinreactivepowerconsumption,typically30%

• Improvementsinpowerfactor,typically0.03-0.1

• Reductioninharmoniclevelswithinthesystem,typically15–30%

• Improvementsinthreephasevoltagebalance,typically10–15%

The powerPerfector is able to achieve all of these benefits through the three winding structure on each phase without recourse to any active (mechanical) or electronic components, or additional “bolt-on” plant or equipment. This has the combined benefits of keeping the design simple with lower risk of failure and a higher overall efficiency.

2.1. Transient Protection• ApowerPerfector makes an electrical supply more robust, and your site better protected. Common transient

events are eliminated by the powerPerfector and is able to prevent transients from causing catastrophic damage to equipment. It also prevents smaller, more common transient events that act to degrade equipment over time prolonging the expected life of electronic equipment.

• ThelevelofprotectionofferedbythepowerPerfector from transients has been fundamental for many of our clients, notably Land Registry, DFID, Orange, RBS and Tesco, to protect their electrical infrastructures.

powerPerfector achieve this benefit due to the primary winding of the powerPerfector sitting in series with the supply acting as a low pass filter, cutting out high frequency events such as voltage transients.

At Burger King’s flagship site a power quality analyser recorded an average of 3.5 transient events per day. Following installation of the powerPerfector the analyser was moved to the output of the unit. This demonstrated that the transient activity had been eliminated. The analyser was then reinstalled on the input to the powerPerfector to show that transient activity was still occurring on the grid.

Kim Pivett, Head of Building Services, Procurement and Building Services team at OFGEM:

. . .“The ability of powerPerfector technology to reduce energy (kWh) consumption at Millbank has been proven, but the technology has also provided OFGEM a range of other benefits. These all contribute to creating a more efficient, robust and reliable electrical supply for the site, and provide further financial benefits on top of the reduced energy costs.

“We were suffering from voltage spikes (transients) which on numerous occasions damaged the lift controls causing them to stop operating. The cost each time to repair the damage was substantial at £800, however in the 1.5 years following the powerPerfector installation there has been no repeat of the issue. We are told that spikes are on the increase due to more switching on the grid so this level of protection is extremely valuable.”


2.2. Reduction in reactive power (kVArh) / improved power factor

• powerPerfector is able to reduce the level of wasteful reactive power consumption in the electrical system typically by ~30%. Reducing reactive power improves power factor, and the powerPerfector typically improves power factor by 0.03-0.10.

• Powerfactorpenaltycharges–whicharenowuncappedintheUK–canbeavoidedifyourpowerfactorisabove0.95. These may appear on your bill as ‘reactive power charge’, ‘kVAr charge’, ‘use of system charge’ or ‘availability charge’. If your power factor is at around 0.9 at the moment, the powerPerfector could remove your exposure to these charges.

• Ingeneral,thestrainonyourelectricalinfrastructureisreducedifpowerfactorisgood.Ifyoursystemiscarrying a high proportion of reactive power, impedances and voltage-drop will be excessive, and overall efficiency will be low. The powerPerfector improves the electrical efficiency of your site.

• ThepowerPerfector yields many of the same benefits as Power Factor Correction, but does not use capacitors, which can be prone to failure. Instead, it helps correct the underlying cause of poor power factor, while saving energy. It is important to note that powerPerfector does not conflict with any power factor correction capacitors already installed.

powerPerfector achieve this benefit by optimising supply voltages to 220V using powerPerfector reduces the reactance of electrical equipment, as it prevents over-excitation of magnetic components. Illustrative example of a client that has seen these benefits are;

In the DEFRA example above a powerPerfector Plus unit was taken through a number of minimum output settings from 227V – 210V. Although the reactive power consumption was lowest at the 210V minimum output the corresponding real power consumption (kWh) was lowest at the 216V minimum output setting. The graph overleaf shows the corresponding improvement in power factor at DEFRA VLA Feeder during those tests.

01/03/08 26/03/08 15/05/08 04/07/0820/04/08 09/06/08 23/08/08 17/09/08 12/10/080

10

20

30

40

50

60

70

90

80

100

Hal

f hou

rly k

VArh

12.5 improvement in average power factor from 0.8 to 0.9

powerPerfector Plus switch settings and savings

F19.9%

E25%

D33.5%

C37.8%

Pre install

Post install

DEFRA–VLAFeederPillar(powerPerfector Plus) – Reactive Power


2.3.Lowerharmonicdistortion• ThepowerPerfector is able to filter harmonics on the mains incomer. Harmonic distortion is on the increase,

leading to apparently random failures of electronic equipment.

• Asthesiteisprotectedfrommains-borneharmonics,disruptionstotheoperationofsensitiveelectronicequipment that could otherwise result from intolerance to harmonic distortion are minimised.

• Thethreatfromdamagingresonanceeffectsisreducedasharmonicdistortionislower,asistheriskoffailure of Power Factor Correction capacitors.

• Theefficiencyofanyequipmentcontainingmagneticcomponentsisimproved–contributingtoenergysavings– as the heating effect of harmonics is reduced. This in turn extends operating life by postponing the breakdown of insulating materials.

• 3rd harmonic is the most severe contributor to high neutral currents – this is filtered by the powerPerfector.

• 5th and 7th harmonics (more generally 6n±1) are common in systems with Variable Speed Drives – these are also filtered by the powerPerfector’s Sdelta windings.

Passive harmonic filtration is achieved by the primary winding, which incorporates the fundamental principles of a line reactor. The magnetic field surrounding the windings are resistant to changes in the waveform characteristic and therefore incoming spikes or changes are broadened out, reducing the total harmonic distortion. The powerPerfector also features a tertiary winding on each phase, connected in delta configuration. It plays no part in the connections to the output circuit, but provides a low impedance path to dissipate harmonics.

The main effects are reduced voltage harmonics coming into a building, lower current harmonics leaving a site and a reduced accumulation of triplen harmonics due to the phase balancing effects of the unreferenced star point. As a result the powerPerfector will reduce 3rd, 5th and 7th order harmonics typically between 15 - 30%.

The design of the powerPerfector means that harmonics are attenuated with minimal change in unit temperature, so there is no cooling requirement.

No tuned filters or active components are used, maximising efficiency and eliminating the risk of unwanted resonance effects.

As part of the NaREC testing programme we established that; the powerPerfector unit does not contribute any harmonic distortion to an electrical system at any frequency; it reduced current harmonic distortion by up to 15.2% for the 3rd harmonic and up to 18.4% for the 5th harmonic; and reduced total harmonic (current) distortion was reduced by up to 12.3%.

01/05/08 17/05/08 20/06/08 23/07/0803/06/08 06/07/08 09/08/08 25/08/08 28/09/0811/09/080.75

0.8

0.85

0.9

0.95

1

Pow

er F

acto

r

Increasing Optimisation

0.88 0.91 0.92 0.93 0.94

Pre install

Post install

DEFRA–VLAFeederPillar(powerPerfector Plus) – 12A Power Factor


Illustrative example of a client that have seen these benefits are;

2.4. Improved phase voltage balance• Theoperationofthree-phaseequipment–particularlyinductionmotors–ismuchmoreefficientifthephase

voltages are closely balanced. A 6% voltage unbalance can cause a 50% increase in motor heating1 and an imbalance of just 1% could void the manufacturer’s warranty2.

• BybalancingthethreephasevoltagesthepowerPerfector helps to reduce the level of triplen harmonics on a site. This leads to reduced neutral currents and temperatures – even though the neutral cable does not pass through the powerPerfector – as triplen harmonics accumulate on the neutral. Lower neutral currents are always desirable, and with an increasing proportion of non-linear loads generating more harmonics than ever before, undersized neutrals are a potential risk on many sites.

The connection between each of the Sstar windings has a current flowing that is in direct proportion to the difference between the three phase voltages. This connection forms an unreferenced star point on the secondary side. In this way, the powerPerfector is able to improve phase voltage imbalance without recourse to active (electronic or mechanical) components.

Illustrative example of a client that have seen these benefits are;

21/12/09 15/01/10 06/03/10 26/04/1009/02/10 01/04/10 21/05/10 15/06/10 29/08/1004/08/1010/07/100

5

10

15

20

25

THD

(%)

27% improvement in THD on Phase 1Pre install

Post install

21/12/09 18/01/10 18/03/10 13/05/1018/02/10 15/04/10 10/06/10 08/07/10 02/09/1005/08/10

0.9

0.8

0.7

0.6

0.5

0.4

0.3

0.2

0.1

0

Volta

ge Im

bala

nce

(%)

14.1% improvement in Voltage Balance

Pre install

Post install

1 Elongo - Voltage Imbalance in Motors - www.elongo.com/pdfs/voltages.pdf2 US Department of Energy Industrial Technologies Program – Eliminate Voltage Unbalance - www1.eere.energy.gov/industry/bestpractices/pdfs/

eliminate_voltage_unbalanced_motor_systemts7.pdf

LondonOffice&DataCentre

LondonOffice&DataCentre


3. Further Benefits

3.1. Reduced maintenance burden• Voltageistypicallysuppliedatthehigherendofthepermittedtolerancerange–VoltagePowerOptimisationwill

correct this by bringing the voltage down to the lower end of this band. As well as reducing energy consumption, this reduces the strain on your equipment, extending its lifespan. For example, a lightly-loaded induction motor operating at an optimum 380V instead of a ‘raw’ 415V experiences less heating and vibration, reducing wear on bearings and prolonging its life.

• Mostequipmentbenefitsfromthelower‘pressure’whenvoltagesareoptimisedforexamplecapacitorbanksinPower Factor Correction systems.

• Whentheseeffectsareaggregated,thebenefittoyoursiteofextendedequipmentlifetimesandreducedreplacement costs will be substantial. The exact saving is difficult for powerPerfector to quantify, but we estimate it to give you a 10%+ reduction of your maintenance and capital replacement costs.

3.2. Business Continuity• ApowerPerfector will ensure that the entire site is protected from common transient events, and as a result will

benefit from a higher level of security of supply. Transients can cause premature failures of equipment which can lead to downtime, loss of earnings and potentially reputational damage.

Martin Illingworth, the Environment Manager at Land Registry says:

. . . “Whilst powerPerfector will enable us to reduce our electricity costs by 13%, the most significant benefit comes from protecting our electronic infrastructure and assets. Land Registry holds the world’s largest property database and guarantees ownership of £1,300 billion of property – data is our business and data protection is critical to our efficient operation.”

3.3. Increased capacity on circuit breakers and lower kVA charges

• ThemaximumdemandofasiteisexpressedinkVA(incorporatingbothrealandreactivepower).Soreducingreactive power reduces the maximum demand of a site, which will lead to reduced kVA demand charges, Agreed Service Capacity (ASC), and increase spare capacity for further growth. An example of reduction in peak, average and baseline consumption can be seen in the chart below, for Carmarthenshire County Council, with the green profile indicating the consumption following installation.

Monday Wednesday ThursdayTuesday Friday Saturday Sunday

30

25

20

15

10

5

0

Cons

umpt

ion

/ kW

h

16.1% reduction in consumption after the installation Pre install

Post install


3.4. Improved HV transformer efficiency• BypreventingharmonicsfromenteringthesecondarysideoftheHVsupplytransformer,thepowerPerfector

is able to improve the transformer’s efficiency and increase its effective capacity. Customers whose utility meter is on the HV side of their transformer may see higher savings as a result.

Contact us For further information on VPO options please contact powerPerfector on +44 (0) 845 601 4723, email [email protected] or visit our website at www.powerperfector.com

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