This session is part of the Clean Energy Regulators Initiative Webinar Programme. Theme 2 - Pressure Points Module 2: Voltage Quality Regulation Voltage quality, sometimes called power quality or technical quality, covers a variety of disturbances in an electrical power system. It is mainly determined by the quality of the voltage waveform and it is an important aspect of the electricity service. Customers are becoming increasingly sensitive to disturbances in voltage quality. This issue is particularly important taking into account the new regulatory frameworks which put strong emphasis on cost reduction, thereby potentially jeopardizing quality. When setting up a quality regulation framework, there are a number of basic issues that need to be considered first. This understanding is crucial in order to make the right choices in order to arrive at an effective voltage quality regulatory system. It is important to clearly define voltage quality and develop suitable indicators. This presentation assesses the issue of what regulators need to consider whenever establishing a voltage quality regulatory framework for distribution networks (i.e. up to 35 kV). It presents a general set of guidelines that regulators could consider in introducing and developing voltage quality regulation. Regulation of five important voltage quality dimensions is considered: short-interruptions, voltage dips, flicker, supply voltage variation and harmonic distortion.

1. Voltage Quality Regulation
Clean Energy Regulators Initiative
Roman Targosz
Walter Hulshorst
13 February 2014

2. Agenda
Introduction
Voltage Quality aspects
Roman Targosz
Copperalliance
Costs of poor voltage quality
Mitigation Measures
General guidelines for Voltage Quality Regulation
Conclusions
| VQ regulation, 2014
Walter Hulshorst
DNV GL

3. Introduction
Why voltage quality is important?
Difference between reliability and VQ.
| Presentation title and date

4. Power Quality; reasons to address
•
Energy sector undergoes market transformation. The liberalization of electricity
market has brought a risk that quality of electricity supply may deteriorate.
Energy regulators have a role to guard this quality.
•
People in private life but also economy rely on continuous supply of electricity.
More renewables or severe weather increase a risk of power blackout. Once the
continuous supply is in place there is a concern about quality of this supply. End
user equipment has certain immunity to voltage disturbances. This immunity and
the performance of supply should create an overlap referred to as compatibility.
•
The immunity of equipment can be increased as well. The crucial role here would
be to define precisely the level of quality which will separate the responsibility.
This concept is known as responsibility sharing. The increase in level of detail in
IEC 61000 series standard or EN 50160 standard helps.
•
When the responsibility for end user power quality problems lays a charge on
suppliers, the crucial thing will be to solve the equation of how much investment
is needed to compensate PQ cost to society. Technical measures are available
but the knowledge on level of PQ impact is not satisfatory to move to the
optimum societal cost balance point.

5. QOS COMPONENTS
CEER identifies three aspects of Quality of Supply:
• Continuity of supply (availability)engineering issue, a function
of network design, state of maintenance and investment Partially
regulated
• Voltage Quality engineering issue, function of network
impedance, load distribution and planning Standardised, not
regulated
• Commercial Quality service response, customer relations,
dispute resolution performance, price Regulated

6. SERVICE QUALITY REGULATION MEANS
MULTIDIMENSIONAL OUTPUT REGULATION
CONTINUITY
OF SUPPLY
VOLTAGE
QUALITY
• UNPLANNED
SUPPLY INTERRUPTIONS
(LONG AND SHORT)
• PLANNED (NOTIFIED)
SUPPLY INTERRUPTIONS
• VOLTAGE INVESTIGATIONS
• VOLTAGE VARIATIONS
• VOLTAGE DIPS / SWELLS
• RAPID VOLTAGE CHANGES
• FLICKER
• HARMONICS
• UNBALANCE
6
GENERATION,
TRANSMISSION AND
DISTRIBUTION
ELECTRICITY
SERVICE
SUPPLY
COMMERCIAL
QUALITY
• CALL CENTERS
• BILLING
• APPOINTMENTS
• RECONNECTIONS AFTER
NON-PAYMENT
DISCONNECTIONS
• READING
• COMPLAINTS
• NEW SUPPLY ESTIMATES
• CONNECTIONS TO
NETWORK
• PROVIDING SUPPLY
• METER INVESTIGATIONS

7. OBJECTIVES OF
SERVICE QUALITY REGULATION
REGULATION
OF QUALITY
MAKE
INFORMATION
AVAILABLE
• SET RELIABLE
MEASUREMENT
RULES FOR
QUALITY
FACTORS
• PUBLISH
ACTUAL
QUALITY
LEVELS
PREREQUISITE
PROTECT
WORSTSERVED
CUSTOMERS
• SET AND
MAINTAIN
GUARANTEED
QUALITY
STANDARDS
• DETERMINE
INDIVIDUAL
COMPENSATIONS
FOR STANDARD
MISMATCHING
PROMOTE
QUALITY
IMPROVEMENT
FAVOUR AND
TEST MARKET
MECHANISMS
• SET AND
MAINTAIN
OVERALL
QUALITY
STANDARDS
• LINK QUALITY
AND REVENUES
(TARIFFS)
• PREFER
CUSTOMER
CHOICE
WHENEVER
POSSIBLE
AND SAFE
INCENTIVE QUALITY REGULATION (P.B.R.)
7
COMPETITION

8. CoS / VQ - changes
Continuity of Supply
Voltage Quality
•
Customer is affected by every
interruption
•
•
Lack of relibility means costs for •
all customers
•
Power interruptions are mainly
caused in the network
•
Customer is not affected until
certain VQ level
Different effects for different
customers
Voltage quality is largely
influenced by (other) customers

9. Reliability / VQ damage functions

10. Interruption vs. dip
UT(r.m.s.)
UT(r.m.s.)
100%
100%
40%
0%
tf
ts
tr
Illustration of a supply interruption
tf – the period of voltage drop;
ts – the period with reduced voltage;
tr – the period with building up voltage
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0%
t
tf
ts
tr
t
llustration of voltage dip; run r.m.s. values
of voltage by 40% voltage dip; explanation
of symbols like in Figure beside

11. Voltage Quality aspects
Technical aspects as defined in EN 50160
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12. EN 50160 – Actors
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13. | VQ regulation 2014
up to few
secods
from 1 µs up to
few seconds
Transient overvoltages
URMS<5%
Overvoltages with
network frequency
Long supply
interruption
URMS > 5% and < 90 %
Plt <= 1
during 95% a week
<= 3 min
5%
> 3 min
Short supply
interruption
Voltage dip
Flicker severity
< ± 5 %, and several times
during a day < ± 10 %
< ± 10 %
during 95% of a week
-10%
Rapid voltage
changes
Supply voltage
variations
The nominal voltage
(declared)
The supply voltage URMS
Power Quality disturbances
up to the value
line-to-line voltage
up to 6 kV
+10%
100%

14. EN 50160 Terms
Definitions concerning the normal (regular) state of the network operation
Network operator – party responsible for operating, ensuring the maintenance of, and if necessary developing, the supply network in a
given area and responsible for ensuring the long term ability of the network to meet reasonable demands for electricity supply.
Network user – party being supplied by or supplying to an electricity supply network.
Nominal voltage Un – is the voltage by which a supply network is designated or identified and to which certain operating characteristics
are referred.
Supply terminal – point in a public supply network designed as such and contractually fixed, at which electrical energy is exchanged
between contractual partners.
This point may differ from, for example, the electricity metering point or the point of common coupling.
Point of common coupling [PCC abbreviation] – the point on a public power supply network, electrically nearest to a particular load, at
which other loads are, or could be, connected.
Supply voltage – is the r.m.s. value of the voltage at a given time at supply terminal, measured over a given interval.
Declared supply voltage Uc – is the supply voltage Uc agreed by the network operator and the network user. Generally declared supply
voltage Uc is the nominal voltage Un but it may be different according to the agreement between network operator and the network user.
Reference voltage (for interruptions voltage dips and voltage swells evaluation) – a value specified as the base on which residual voltage,
thresholds and other values are expressed in per unit or percentage terms. For the purpose of this standard, the reference voltage is the
nominal or declared voltage of the supply system.
Frequency of the supply voltage – repetition rate of the fundamental wave of the supply voltage measured over a given interval of time.
Nominal frequency – is the nominal value of the frequency of the supply voltage.
| Presentation title and date

15. Normal operating conditions
Levels of voltage have been divided as follows:
High voltage – voltage whose nominal r.m.s. value is 36 kV<Un<150 kV,
Medium voltage – voltage whose nominal r.m.s. value is 1 kV<Un≤36 kV,
Low voltage – voltage whose nominal r.m.s. value is Un≤ 1 kV.
Because of existing network structures, in some countries the limit between MV and HV can be different.
Normal operating condition – operating condition for an electricity network, where load and generation demands
are met, system switching operations are made and faults are cleared by an automatic protection system, in the
absence of exceptional circumstances, i.e.:
• temporary supply arrangement;
• in the case of non-compliance of a network user’s installation or equipment with relevant standards or with the
technical requirements for connection;
• exceptional situations, such as:
•
exceptional weather conditions and other natural disasters;
•
third party interference;
•
acts by public authorities;
•
industrial actions (subject to legal requirements);
•
force majeure;
•
power shortages resulting from external events.
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16. Compatibility
network operator
probability density of immunity
of equpment on disturbances
(classes of electomagnetic
environment 1, 2, 3)
immunity level
%?
e.g. (EN 50160)
capital costs
in a supply network
| Presentation title and date
(e.g. EN 61000-3-x,
characteristic CBEMA)
costs of production
of equipment
probability density
probability density
planning
level
compatibility level
and a risk of damage of
equipment
probability density to adhere
the supply parameters
network user,
manufacturer of equipment

17. Viaduct – Vehicle Analogy
Planning level
Compatibility level
Equipment immunity level
17

18. EN 50160
For systems with no synchronous
connection to an interconnected system
(e.g. supply system on certain islands)
For systems with
synchronous connection to
an interconnected system
Duration
Duration
Parameter
50 Hz ± 1 %
during
50 Hz ± 2 %
during
(i.e. 49,5 Hz ÷ 50,5 Hz)
99,5%
(i.e. 49 Hz ÷ 51 Hz)
95%
50 Hz + 4% / -6%
of a year
during
50 Hz ± 15 %
of a week
during
(i.e. 47 Hz ÷ 52 Hz)
100 %
(i.e. 42,5 Hz ÷ 57,5 Hz)
100 %
Power frequency
voltage
Under normal operating
conditions excluding the
periods with interruptions
•
Un ± 10 %
Supply
•
| Presentation title and date
of the time
during each period of
one week 95 % of the
10 min mean r.m.s.
value;
all 10 min mean r.m.s.
values of the supply
voltage shall be within
the range of Un +10%
/ -15%
also for special remote network users
•
Un + 10% / -15%.
Network users should be informed of the
conditions.
In accordance with relevant product and
installation standards, network users’
typically designed to tolerate supply
voltages of ±10% of Un.
•
of the time
during each period of
one week 95 % of the 10
min mean r.m.s. value
±10% of Un;
all 10 min mean r.m.s.
values of the supply
voltage shall be within
the range of Un +10% / 15% 1)

19. 95 percentile – philosophy of EN 50160
Odered diagram of long term flicker severity Plt
1,60
1,40
1,20
Plt
1,00
∆ Plt
0,80
0,60
0,40
0,20
0,00
0
100
200
95%
| Presentation title and date
300
400
500
600
700
number 10 min measurement over a week
800
900
1000

20. EN 50160 voltage dips
Residual voltage
Duration
U%
ms
10 ≤ t ≤ 200
200< t ≤500
500< t ≤1000
1000< t≤5000
5000<t ≤60000
90 > u ≥ 80
CELL A1
CELL A2
CELL A3
CELL A4
CELL A5
80 > u ≥ 70
CELL B1
CELL B2
CELL B3
CELL B4
CELL B5
70 > u ≥ 40
CELL C1
CELL C2
CELL C3
CELL C4
CELL C5
40 > u ≥ 5
CELL D1
CELL D2
CELL D3
CELL D4
CELL D5
5>u
CELL X1
CELL X2
CELL X3
CELL X4
CELL X5
| Presentation title and date

21. Voltage dips immunity
Type II
Type I
Type III
375
300
Immunity limit
on the overvoltages
100
0
Range of tolerated
voltage
disturbances
% Un
200
100 µs
20 ms
10 ms
| Presentation title and date
Immunity limit on the voltage dips
and short supply interruption
1 ms
1 µs
t
1s
1min
1hr 1day

22. EN 50160 – harmonic limits
during each period of one week, 95% of
the 10 min mean r.m.s. values
Odd harmonics
Not multiples of 3
Order
Relative
amplitude
Even harmonics
Multiples of 3
Order
Relative
amplitude
h
h
Order
h
uh
uh
Relative
amplitude
uh
5
6,0 %
3
5,0 %
2
2,0 %
7
5,0 %
9
1,5 %
4
1,0 %
11
3,5 %
15
0,5 %
6 … 24
0,5 %
13
3,0 %
21
0,5 %
17
2,0 %
19
1,5 %
23
1,5 %
25
1,5 %
| Presentation title and date

23. Unbalance
Under normal operation conditions, during each period of one week, 95% of the 10 min mean r.m.s. values of the negative phase sequence
component (fundamental) of the supply voltage shall be within the range 0% to 2% of the positive phase sequence component (fundamental).
In this European Standard only values for the negative sequence component are given because this component is the relevant one for the
possible interference of appliances connected to the system.
In some areas with partly single phase or two phase connected network users’ installations, unbalances up to about 3% at three-phase supply
terminal occur.
| Presentation title and date

24. Measurement
CLASSES OF MEASUREMENT METHODS ACCORDING TO EN 61000-4-30:2009. Electromagnetic compatibility (EMC), Part 430: Testing and measurement techniques – Power quality measurement methods.
For each parameter measured, three classes (A, S and B) are defined. For each class, measurement methods and
appropriate performance requirements are included.
• Class A
• This class is used where precise measurements are necessary, for example for contractual applications, that
may require resolving disputes, verifying compliance with standards etc.
• Any measurements of a parameter carried out with two different instruments complying with the requirements
of class A, when measuring the same signals, well produce matching results within the specified uncertainty
for that parameter.
• Class S
• This class is used for statistical applications such as surveys or power quality assessment, possibly with a
limited subset of parameters. Although it uses equivalent intervals of measurement as class A, class S
processing requirements are lower.
• Class B
• This class is defined in order to avoid making many existing instruments designs obsolete.
• Class B methods are not recommended for new designs.
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25. Costs of poor voltage quality
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26. PQ cost summary
Dips_and_short_interruptions
100
70
Long_interruptions
Labor
63,6
20,97%
Harmonics
Surges_and_transients
85
28,0%
86,5
28,5%
Flicker_unbalance_earthing_and_EMC
Process_slowdown
Equipment
60
Other_cost
Dips 52,5 € bln
Short inter. 34 €bln
80
64
21,1%
WIP
PQ cost in EU >150 bln €
50
PQ cost bln €
PQ cost bln €
44,6
14,69%
60
53,4
17,6%
51,2
16,89%
41,3
13,62%
40
37,9
12,5%
36
11,85%
30
40
20
20
10
4,6
1,51%
0
0,2
0,06%
Industry
4,1
1,36%
1,5 1,8 1,1 2,1
0,5% 0,6% 0,35% 0,71% 0
0,02%
Services
Sector
6,4
2,11%
1,3
0,41%
4,2
1,38%
2,9
0,94%
1,4
0,45%
0
Total
Industry
3,3
2
0,9 1,08%
0,4 0,1
0,65%
0,28%
0,13%
0,04%
Services
Sector
3
0,98%
2,2
0,73%
Total

27. PQ cost conclusion from LPQI survey
•
To arrive at a statistically significant and acceptable model the survey sample was divided
into two sub-samples - “Industry” and “Services”.
•
The cost of wastage caused by poor PQ for EU-25 according to this analysis exceeds
€150bn. “Industry” accounts for over 90% of this wastage.
•
Industry is hardest hit
•
Dips, short interruptions, surges and transients account for 80-90% of the €150bn
financial costs/ wastage
•
Equipment damage and operational waste (unrecoverable work in progress &
underperformance) account for similar proportions of the totals identified
•
For the most sensitive industrial sectors representing €3,63 trillion (or 20% of EU25 overall
turnover) PQ costs amounts about 4% of their turnover.
•
The apparently insignificant contribution of “Services” to total PQ costs (0,142% of
turnover) may result from certain cost underestimation as this sector often experience
problems in an office environment where correctly distinguishing between a PQ cause
and other root cause may be difficult.

28. The Cost of PQ and Reliability to the U.S.
Economy
$Billion
120
100
Total Annual Cost of Power
Outages and PQ Disturbances
by Business Sector
$66.6-135.6
80
60
PQ Disturbance
Power Outage
$34.9
40
20
Cost of:
TOTAL
$119 - $188 Billion
$14.3
$6.2
0
Digital
Economy
Continuous
Process
Mfg.
40% GDP
EPRI IntelliGrid
Fabrication
& Essential
Services
Other US
Industry
60% GDP
Source: Primen
Study: The Cost
of Power
Disturbances to
Industrial &
Digital Economy
Companies

29. Costs from Unmitigated PQ Phenomena
EPRI IntelliGrid Study – Average Costs Across All Businesses

30. Italian Study (2007) about impact of voltage dips on
industry
•
Politecnico di Milano (400 kW - 31 MW): mediana and (mean)
•
10.7 €/kW (61.7 €/kW)
•
•
full sample:
excl. „0” direct cost:
21.3 €/kW (74.6 €/kW)
CESI Ricerca, 2004 (20 kW - 160 MW): mean of PQ disturbances
together: 6 €/kW

31. PQ cost – historical examples (1)
T. Andersson and D. Nilsson, in "Test and evaluation of voltage dip immunity," STRI AB and Vatenfall
AB 27 Novenber 2002,
Sensitivity of different industries to voltage dips expressed in estimated dips cost per industry. The
highest position in this ranking is occupied by semiconductor industry which, according to some other
sources, experience the highest level of voltage dips cost compared to electricity bill or company
turnover of any sector.
Different types of industries
Textile industry
Plastics industry
Glass industry
Paper industry
Steel industry
Semiconductor industry
€1 000
€10 000
€100 000
€1 000 000
cost [€]
€10 000 000

32. PQ cost – historical examples (3)
Voltage dips cost per event based on study carried
out in the University of Manchester former UMIST by
J. V. Milanovic and N. Jenkins, "Power quality cost
for manufacturing industries," presented on EdF
workshop in Paris, 2003.
Financial losses caused by voltage sags taken from
D.Chapman, "The cost of poor power quality," Copper
Development Association November 2001
Industry
Industry
Duration
Cost/sag
UK steel work
30%
For 3.5 cycles
£250k
US glass plant
Less than 1 s
$200k
US
computer
centre
2 second
$600k
US car plant
Annual
exposure
$10M
South Africa
Annual
exposure
$3B
Typical financial
loss per event (€)
Semiconductor
production
3,800,000
Financial trading
6,000,000
Computer centre
750,000
Telecommunications
30,000
Steel works
350,000
Glass industry
250,000
per hour
per
minute

33. The reasons for investigating the cost of poor PQ
•
Building awareness of the potential magnitude of PQ costs which may largely affect
the productivity of the company
•
While statistics and indicatory values are helpful, no two companies, even when
operating in the same sector, will be equally vulnerable to PQ disturbances. Individual
surveys are needed
•
As PQ becomes more and more the subject to contract between a user and a supplier,
the cost of PQ needs to be quantified to establish a measure of a value of improved PQ
for which the user is going to pay a premium price or receive compensation if PQ is
inadequate
•
In case of failure caused by a PQ event for which the supplier is contractually liable,
the amount of compensation will need to be determined. PQ survey will allow a
prompt and accurate determination of the amount of PQ loss.
•
Awareness of the cost of PQ will help to minimise it. Once the PQ cost is known many
small and simple incremental improvements are easily justified and possible.
•
Finally PQ cost knowledge is a tool for regulators to set incentives for suppliers. The
benefit should retain for the whole society

34. Leonardo ENERGY

35. Leonardo Academy
http://www.leonardo-academy.org/

36. Thank you
roman.targosz@copperalliane.pl
| Presentation title and date

37. ENERGY
REGULATORY GUIDELINES IN SETTING
UP A VOLTAGE QUALITY MONITORING
FRAMEWORK
W. Hulshorst
13 feb 2014
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SAFER, SMARTER, GREENER

38. Agenda
 Introduction
 Voltage Quality aspects
 Costs of poor voltage quality
 Mitigation Measures
 General guidelines for Voltage Quality Regulation
 Conclusions
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39. Mitigation measures (technical)
Since most of the power quality problems are cost related this justifies the investments in
mitigation technologies by the power company or the customer.
A wide range of technology is available to make this possible. In general, technical solutions
that increase voltage quality can be at 4 levels:
The choice for a mitigation method depends on:
 The nature of the disturbance generated and / or to be prevented,
 The required level of performance,
 The financial consequences of malfunction,
 The time required for a return on the investment,
 Practices, regulation and limits on disturbance set at the grid operator.
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40. Mitigation measures
 Premium contracts:
– The availability of sophisticated and
sensitive net technologies has led
customers to demand higher levels
of power quality. To meet these
needs, some utility companies have
set up premium power quality
contracts for their customers
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 Labelling:
– In most countries Minimum
Standards are defined for voltage
quality. This anticipates the issue
that if a minimum level of quality is
met, the customer is not interested
in better quality. Some customers
need higher quality than the
minimum standards.

41. Guidelines for voltage quality regulation
 When setting up a voltage quality regulation framework, there are a number of
basic issues that need to be considered first. This understanding is crucial in order
to make the right choices in order to arrive at an effective voltage quality
regulatory system.
 The main issues to be considered during this process are identified:
1. develop a good understanding of what voltage quality is and how it can be
measured.
2. clearly defining the objective one would like to pursue with respect to the
voltage quality and
3. choosing the appropriate quality control in order to achieve the defined
objectives
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42. Measuring of voltage quality
 The ability to measure voltage quality clearly is a precondition for setting up an
effective voltage quality regulatory framework.
 But before measuring, of even more importance is the need to clearly define
“voltage quality” and develop suitable indicators. Quality measurement is the
fundament for any quality regulation system. It is of utmost importance that the
data that feeds into the quality control is accurate. These data forms the input of
the regulatory process. Clearly, if the underlying data is wrong, so will be the
outcome.
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43. CEER conclusions on voltage quality monitoring (1)
 Voltage quality monitoring are use full tools for regulation:
There are sufficient applications with advantages that in the end fall to
the network user to justify having a voltage-quality monitoring program.
A monitoring program can be fully under the control of the regulator, or,
installed and operated by the network operator with the regulator getting
access to the data.
 Diversification of indices and methods is to be avoided:
A number of voltage quality monitoring programs are already in place in
different countries. There are large differences between these programs – this
makes it difficult to compare the results and exchange knowledge and
experience – harmonisation is needed! (choice of monitor locations, types of
disturbances monitored, characteristics recorded, indices calculated)
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44. CEER conclusions on voltage quality monitoring (2)
 Voltage quality monitoring programs should be funded through network tariffs:
The most common way of funding such a program is through the
network tariffs. This can however vary between countries based on the
local tariff structure and regulation.
 Making results available is important:
Publication of the results (including compliance with voltage quality
regulation and important trends) and making data available in other
ways are important parts of a voltage-quality monitoring program.
 Keep other applications in mind
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45. CEER conclusions on voltage quality monitoring (3)
 Keep other applications in mind:
When setting up a voltage quality monitoring program, it is important to
consider all possible applications. Even if the purpose of a program is
initially limited, small changes to the set-up of a program or to the kind
of parameters recorded or calculated, can allow future applications at
no or very small extra effort (setting up of such a program should be
done in close cooperation between NRAs and network operators).
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46. Define the objective
 Once a clear measure of voltage quality has been defined and the relevant
indicator to be measured has been identified, the next step is to establish what
the quality objective is:
1. the existing level of performance should be quantified and possibly, compared
with respect to of international best practice.
2. the quality level that one ideally would like to achieve needs to be defined.
Network Costs
Interruption Costs
Total Social Costs
Optimum
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Quality

47. Appropriate quality control to achieve the objectives
 Once the regulator has identified the appropriate quality indicator, is able to
measure it, and has an idea about what performance level should be achieved,
the next step is to choose a suitable regulatory control to help achieve that
objective.
 There is however a second criteria that also need to be taken into account namely
whether the quality control can actually be implemented or not. Generally
speaking, three types of quality controls can be distinguished:
1. under performance monitoring, the regulator monitors the performance of the
network company and where applicable makes this information available to
the public.
2. the regulator can apply a minimum standard. Here, a minimum level of
performance is prescribed; not meeting this standard leads to a penalty.
3. under a quality incentive scheme, a more continuous relationship between
quality performance and financial outcome can be imposed.
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48. 1 Performance monitoring
 Performance monitoring is relatively simple to implement and requires limited
regulatory involvement. The basic idea is to require the network company to
report on its voltage quality performance to the regulator.
 The regulator can then decide to make this information available to the public
 Performance monitoring is the weakest form of quality control as it only provides
indirect incentives to the utility. However, it is also the simplest to implement as it
requires relatively little effort by the regulator.
 Also, in terms of data requirements, performance monitoring can be limited to a
number of strategic locations within the network thus eliminating the need for
measuring extensively throughout the network or, in the extreme case, at each
individual customer connection point.
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49. 2 minimum standards
 Minimum standards dictate a minimum level to be achieved for a certain
performance aspect. In case of not meeting this standard, the utility can be
penalized financially or otherwise.
 In the case that the regulator aims at increasing performance, minimum
standards provide clear guidelines about what quality network operators should
aim at.
 They set quantitative targets for the companies to achieve. If combined with
financial incentives for not meeting the standards, minimum standards can be
very effective quality controls.
 The minimum standard can be derived directly from standards which are already
adopted and used within the power sector industry. For example, in Europe, the
European Standard EN 50160 has been generally considered as a reasonable
starting point to establish voltage quality regulation systems
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50. 3 Incentive scheme
 An incentive scheme can be considered as an extended minimum standard. Under
a minimum standard, the utility pays a penalty in case it does not meet a certain
prescribed level. Under an incentive scheme, a more continuous relation is
imposed between price and quality. Each performance level results in a financial
incentive, which varies with the gap between actual performance level and the
target level.
 An incentive scheme extends the minimum standards and makes the financial
incentive (being a penalty or a reward) a direct function of actual performance..
 Incentive schemes are useful if one is aiming at maintaining existing levels of
performance or improve the performance.
 But even though theoretically superior, incentive schemes have serious practical
limitations:
–
–
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it is difficult to exactly measure customer costs due to lack of quality.
the collection of adequate and high-quality data.
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51. Conclusions
 It is crucial that the objectives of quality regulation are clearly defined. This helps
to increase the effectiveness of the regulatory system and reduce the risks of
adverse effects
 The definition of the voltage quality objective follows logically from the perceived
difference between current and desired levels of voltage quality. Socio-economic
analysis identified the optimal quality level as being a desirable objective.
 Three types of quality controls can be distinguished:
– Performance monitoring
– A minimum standard
– An incentive scheme
 Typically, the European Standard EN 50160 is used as the basis for setting
minimum standards. Where needed, regulators may choose to go beyond the
minimum limits imposed by the EN 50160
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52. Thanks
More information needed?
Walter.hulshorst@dnvgl.com
+3126 356 24 32
www.dnvgl.com
SAFER, SMARTER, GREENER
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