MEDIUM VOLTAGE COMPENSATION SYSTEMS · MEDIUM VOLTAGE CAPACITORS 05 Medium voltage compensation...

M E D I U M V O LT A G E C O M P E N S A T I O N S Y S T E M S

CONDO D2131636

M IКA

MIКA powered by Condensator Dominit

WE DEVELOP, DESIGN AND MANUFACTURE OUR MIКA PRODUCTS IN GERMANY

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The MIКA product family of Condensator Dominit GmbH stands

for premium systems and sophisticated concepts for compen-

sation and filtering of medium voltage and high voltage grids.

Large industrial plants, renewable energy generators, distri-

bution networks and many other operators of medium voltage

systems face the challenge to insure that their grid connections

comply with all standards and requirements. To ensure such

compliance, a capacitive / inductive componet and/or an appli-

cation specific filter concept is often needed.

The products of the MIКA series provide the appropriate solu-

tion to any problem. We have been your Number One contact

for standard products as well as for customized overall concepts

and the related service ever since 1975. Reference systems in all

parts of the world and a large community of satisfied customers

testify to our high quality and reliability.

Make you grid safe now with MIКA!

MIКA MEDIUM VOLTAGE COMPENSATION SYSTEMS

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Medium voltage compensation systems

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POWER QUALITY ISSUES IN HIGH VOLTAGE GRIDS

Frequency converters

Control frequency

UPS systems

Renewable energy generators (wind farms/solar parks)

Motor heavy starting

Inductive loads

Power inverters (e.g. in photovoltaic systems)

Arc and induction furnaces

Welding systems

Cable capacitances

Switching operations by the utility company

Electrolytic processes

Water works / paper machinery

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DIRECT EFFECTSDeviance from norm

Voltage distortion

Resonance excitation

Voltage asymmetry

Grid load due to distortion reactive power (cos phi)

Transformer overheat

Distortion of the ripple control signal

Voltage fluctuation

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CONSEQUENCESLoss of warranty claims

Reduced life of plant and equipment

Higher noise emission by transformers and consumers

Temperature rise in transmission equipment

Violation of grid connection conditions

Denial of grid connection (by utility company)

Increased CO2 emission

Higher cost

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MEDIUM VOLTAGE CAPACITORS

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All-film technology

2 to 4 mounting brackets / indoor and outdoor application

1 to 24 kV

Stainless steel housing

Jarylec (PCB free)

Typical use as S01 (1 capacitor per phase)

All-film technology

Low-loss, approx. 0.2 W/kvar

Foldered foil

Faradol 600 / Jarylec (PCB free)

With or without internal fusing


1 to 20 kV each capacitor

Suitable for high performance applications > 1 Mvar

Typical use as E03 (3 pcs. with pressure switch), E06/G06 (6 pcs. with unbalance monitor)

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Single-phase capacitors – E &G series

All-film technology


Faradol 600 / Jarylec (PCB free)


Suitable for medium performance applications > 300 kvar to < 1 Mvar

Typical use as C03 (3 capacitors with unbalance monitor)

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Split-phase capacitors – C series

All-film technology


1 to 12 kV


Suitable for small performance applications < 800 kvar

Typical use as B01-B03 (1 to 3 capacitors with pressure switch)

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3-phase capacitors – B series

Surge capacitors – S-Series

Example: E/Go6 (YY with converter + unbalance monitor)

Example: C03 (YY with converter + unbalance monitor)

Example: B03

Example: S03

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CBANK

The CBANK product series is the basic

series of the MIКA family. Typical appli-

cations of capacitors without reac-

tors are, for example, transformer or

motor fixed compensation in grids

with negligible harmonic load. The

standard product range includes indi-

vidual capacitors as well as banks of

up to 12 capacitor units. Systems with

single-phase, 3-phase and split-pha-

se capacitors are available. For mo-

nitoring the capacitors units, pressu-

re switches (change over contact for

reporting internal defects) can be in-

tegrate in small power systems whe-

reas larger power systems come with

an unbalance monitor with current

transformer and relay. The mechani-

cally protection concept provides for

IP00 as basic version for installation

in closed electrical operating facili-

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MIКA-CBANK

FEATURES

Economic construction

Robust design

Optimum natural cooling

Low-loss all-film technology

PCB free

B-/C-/E-/G series

Small power system with pressure switch

High power system with unbalance

monitoring

Hot-dip galvanized and painted hoods

Optional inrush current limiting chokes

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ties, The IP54 version offers shock-

proofness and weather-protection, in

addition.


More interesting facts about choking: pages 24 to 27.

TECHNICAL SPECIFICATIONS – MIКA-CBANK

Operating voltage

Nominal frequency

Insulation level

Nominal power

Type series

Protection

Ambient temperature

Installation site

Altitude

Impregnating material

Commodity code

Optional

1 kV – 24 kV*

50 / 60 Hz

20 / 60 kV

28 / 75 kV

38 / 95 kV

50 / 125 kV

50 kvar - 9900 kvar*

B series (B01-B03)

(3-phase capacitors + pressure switch)

C series (C03)

(capacitors with 2 power sections) +

unbalance monitoring

E-/G series (E06, G06)

(single-phase capacitor +

unbalance monitoring)

IP00 / IP54*

– 25 °C to +40 °C*

Indoor or outdoor

< 1000 m above sea level

Faradol / Jarylec

85.32.10.00

Inrush current limiting reactors

Terminal box for pressure switch

IP54 housing

TAG number

C5-I finish

* Other versions available on request

Technical modifications and errors excepted

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LBANK

The LBANK product series of the MIКA

family builds on the CBANK basic versi-

on. Typical applications of reactor pro-

tected capacitor installations of type

LBANK are, for example, transformer or

motor fixed compensation in modern in-

dustrial grids with harmonic load (e.g.,

according to IEC 61000-2/4 class 2). The

LBANK climate concept provides for

the spatial separation of capacitors and

reactor. The reactor and the power

connections of the capacitors are located

within the 2 mm thick housing whereas

the temperature sensitive capacitors are

cooled naturally and are therefore placed

outside. Like CBANK, systems with 1 up

to 12 capacitor units are available. The

system is mounted in a hot dip galvani-

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MIКA-LBANK

FEATURES

Simply clever

Cooling by convection

Robust design


Polygap® choke with double

impregnation

PCB free

Ready to connect

One transport unit

IP34 D housing

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zed steel frame, which makes the system

easy to transport.


More interesting facts about choking: pages 24 to 27.

TECHNICAL SPECIFICATIONS – MIКA-LBANK

Operating voltage

Nominal frequency

Insulation level

Nominal power

Type series

Tuned frequency

Protection

Ambient temperature

Installation site

Altitude


Standard

Commodity code

Optional

1 kV - 15 kV*

50 / 60 Hz

20 / 60 kV

28 / 75 kV

38 / 95 kV

50 kvar - 5500 kvar*

B series (B01-B03)


C series (C03)

(capacitors with 2 splitted phases +


E-/G-series (G06, G06/G12)

(1-phase capacitors + unbalance

monitoring)

189 Hz (7 %)* or filter circuit

IP34D*

– 15 °C to +35 °C*

Indoor or outdoor


Faradol / Jarylec

IEC 60871-1 / IEC 60071 / IEC 60282-1 / VDE 101

85.37.20.91

Back-up fuse

Unbalanced circuit monitoring relay

Stainless steel terminal box

additional weather roof

and other optional features



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The MIКA RCOMP series is the system

of choice when large controlled power is

needed.

The rack design makes the RCOMP con-

cept compact and easy to transport. All

components (except the reactor) are

preassembled in the factory and only re-

quire correct positioning on site. Particu-

larly in high-power systems substantially

higher power per step is available than,

for example, from an enclosed system.

The system is installed in a separate lo-

cked electrical equipment room. A se-

parate cabinet (e.g. C-65-A) contains all

required monitoring and control units;

the control cabinet can optionally be

connected to an available process con-

MIКA-RCOMP

FEATURESCompact design

High power per step

Fuse monitoring

Polygap® reactors


Robust hot-dip galvanized steel rack

Flexible extension

Optional system visualization and

linkup with PLC

Touch panel in control cabinet

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trol system/centralized instrumentation

and control system.

RCOMP


More interesting facts about ventilation: pages 24 to 27.

TECHNICAL SPECIFICATIONS – MIКA-RCOMP

Operating voltage

Nominal frequency

Insulation level

Nominal power

Type series

Design versions

Tuned frequency

Protection

Ambient temperature

Installation site

Altitude


Norm

Optional

1 kV - 24 kV*

50 / 60 Hz

20 / 60 kV bis 50 / 150 kV

150 kvar - 20 000 kvar*

B./C-E- series

-F (fixed step)

-E (with contactor for external actuation)

-A (system with automatic control)

189 Hz (7 %)*

141 Hz (12,5 %)*

LINR inrush current limiting reactors

or filter application

IP00

– 15 °C to 40 °C*

Indoor


Faradol / Jarylec

IEC 60871-1 / IEC 60071 / IEC 60282-1 / VDE 101

Phase current transformer

Vacuum contactor or power circuit breaker

Discharge voltage transformer

Voltage transformer, definite-time overcurrent-

time protection, etc.

Control cabinet

Circuit breaker, grounding switch

Oil pan

Surge arrester



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ECOMP

The ECOMP product series is a metal-en-

closed, shockproof control cabinet sys-

tem for compensation and filter appli-

cations up to maximum grid nominal

voltage of 15 kV. Typical applications of

this type of system are in electrical ope-

rating facilities. Generally, the ECOMP

system is available in three versions:

ECOMP-F as fixed step with external ac-

tuation without own switching device,

ECOMP-E as externally controlled unit

with integrated contactor, and ECOMP-A

as automatically controlled system with

integrated control and monitoring func-

tions. In addition, the following standard

reactor versions are available with reac-

tors type: LINR inrush current limiting re-

actor), 7 % (189 Hz) or the application as

filter for several harmonics. In addition to

the standard solutions, the ECOMP sys-

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MIКA-ECOMP

DESIGN VERSIONS

ECOMP-F, equipped with:

HRC fuses, incl. fuse monitoring

1 set of LINR or filter circuit reactors

Position indicator for up-line

power circuit breaker / grounding

switch

Discharge time monitoring

Indicator light - system ready

Indicator light – discharge time running

Indicator light - Fault

Emergency stop switch

Mimic on the front

Door monitoring

Separate low voltage compartment

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tem is ideal for customized projects and

modifications.

ECOMP-E, same as ECOM-F:

+ Vacuum contactor

+ Switching monitoring

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ECOMP-A, same as ECOM-E:

+ Reactive power controller

+ Central control in the incoming feeder unit

+ Optional DMC controller

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More interesting facts about discharge time: pages 24 to 27.

TECHNICAL SPECIFICATIONS – MIКA-ECOMP

Operating voltageControl voltageNominal frequencyInsulation level

Nominal powerAs filter applicationCapacitor types

Design versions

Tuned frequency

ProtectionAmbient temperature Installation siteAltitudeImpregnating materialNormCommodity codeFinishDimensions (W x D x H)

Optional

1 kV - 15 kV*230 VAC / 220 VDC *50 / 60 Hz20 / 60 kV28 / 75 kV38 / 95 kV50 kvar – 2500 kvar* each stepup to max. 230 Arms each stepB series (B01-B03)(3-phase capacitors + pressure switch)C series (C03)(capacitors with 2 power sections +unbalance monitoring)E-/G series (E03, E06, G06)(single-phase capacitor + unbalance monitoring)-F (fixed step)-E (with contactor for external actuation)-A (system with automatic control)189 Hz (7 %)*Filter applicationLINR inrush current limiting reactorIP21 - IP4xD*0 °C to 35 °C*Indoor< 1000 m above sea levelFaradol / JarylecIEC 60871-1 / IEC 60071 / IEC 60282-1 / VDE 10185.37.20.91RAL 7035Capacitor unit: 1000 x 1200 x 2054 mmIncoming feeder /reactor unit: 800 x 1200 x 2054 mmBase 100 / 200 mm, door lock with discharge time monitoring, discharge voltage transformer, phase current transformer, heating, ventilation, grounding switch, power circuit breaker, definite-time overcur-rent-time protection, etc.



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SCOMP

Enclosed medium voltage systems are

frequently preferred solutions whe-

re the safety of the equipment and

of people is important. To provide a

higher level of safety for operators

when a fault (short-circuit/arc inside

the system) occurs, this system type

has strong double walls, door locks,

pressure relief flaps with monitoring,

a sophisticated ventilation concept,

arcing fault deviation plates, parti-

tions between the different units and

a number of other features. Like with

the ECOMP system, the SCOMP also

is available in three versions: -F / -E /

-A. Each of these versions can be im-

plemented both as pure power factor

correction and as filter application. Be

safe, take "Scomp".

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MIКA-SCOMP FEATURES

Tested for resistance to accidental

arcing 25 kA/15 acc. to IEC 60298

1990 IAC test

Max. grid voltage 12 kV

up to 6 compensation steps

(totally max. 12 Mvar)

Protection IP41D

2 mm thick double walls and doors

Indicator light - Fault

Temperature, unbalance, door and

pressure relief flap monitoring

Large variety of expansion and

enhancement options

Integrated grid analyzer with several

communication interfaces

Door lock

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More interesting facts about accidental arcing: pages 24 to 27.

TECHNICAL SPECIFICATIONS – MIКA-SCOMP

Operating voltage

Control voltage

Nominal frequency

Insulation level

Nominal power

Capacitor types

Design versions

Tuned frequency

Protection

Ambient temperature

Installation site

Altitude


Norm

Commodity code

Finish

Dimensions (W x D x H)

Optional

1 kV - 12 kV*

230 VAC / 220 VDC* (fused)

50 / 60 Hz

20 / 60 kV

28 / 75 kV

50 kvar – 2000 kvar* each step

C series (C03)

(capacitors with 2 power sections +


E-/G series (E03, E06, G06)

(single-phase capacitor +


-F (fixed step)



189 Hz (7 %)*

LINR inrush current limiting reactor

IP41D

0 °C to 35 °C*

Indoor

< 1000 m above sea level*

Faradol / Jarylec

IEC 60871-1 / IEC 60071 / IEC 60282-1 / VDE 101

85.37.20.91

RAL 7035

Capacitor unit: 1000 x 1200 x 2054 mm

Incoming feeder / reactor unit: 800 x 1200 x 2054 mm

Discharge voltage transformer, heating, ventila-

tion, voltage transformer, definite-time overcur-

rent-time protection, incoming feeder with

optional breaker / grounding switch, touch panel,

link-up with process control system, etc.



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WCOMP

The WCOMP compensation units are the

ideal choice when sensitive components

must be installed outdoors. Medium vol-

tage components and control are instal-

led in a stainless steel station building to

protect them from inclement weather.

This system type is often used as cent-

ral compensation, e.g., of wind farms,

as tele command blocking filter for grid

link-up or as harmonic filter. The housing

dimensions vary from 1.8 to 7 meters

in length and the maximum power is

approx. 7 Mvar (10 kV). As with the R-, E-,

and SCOMP series, the WCOMP also co-

mes in three versions: WCOMP-F as fixed

step with external actuation and without

own switching device, WCOMP-E as ex-

ternally controlled unit with integrated

contactor, and WCOMP-A as automati-

cally controlled system with integrated

control and monitoring functions. In ad-

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MIКA-WCOMP

dition, four standard reactors versions

are available for this series: LINR (inrush

current limiting reactor), 7 % (189 Hz),

tele command blocking filter applicati-

on or as filter for several harmonics. In

addition to the standard solutions, the

SCOMP system is ideal for customized

projects and modifications.

FEATURES

Patented labyrinth ventilation system

Ready-to-connect overall system

Robust design

Low-voltage section in separate

control cabinet

One transport unit

IP34D

Stainless-steel housing (painted)

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More interesting facts about IP protection flaps: pages 24 to 27.

TECHNICAL SPECIFICATIONS – MIКA-WCOMP

Operating voltage

Control voltage

Nominal frequency

Insulation level

Nominal power

Capacitor types

Design versions

Tuned frequency

Protection

Ambient temperature

Installation site

Altitude


Norm

Finish


Optional

1 kV - 20 kV*

230 VAC / 220 VDC (fused)*

50 / 60 Hz

20 / 60 kV

28 / 75 kV

38 / 95 kV

150 kvar bis 7000 kvar*

B series (B01 – B03)


C series (C03)

(capacitors with 2 power sections +


E-/G series (E06, G06)

(three-phase capacitors +


-F (fixed step)



189 Hz (7 %)*

210 Hz (5,67 %)*


IP34D*

– 20 °C to 40 °C*

Outdoor


Faradol / Jarylec

IEC 60871-1 / IEC 60071 / IEC 60282-1 / VDE 101

RAL 7032

on request

Discharge transformer, heating, lighting, voltage

transformer, definite-time overcurrent-time

protection, pressure relief flaps (roof), forced

ventilation, double locking system, cable grounding

electrode, incoming disconnector, etc.



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MIКA-BCOMP


BCOMP

If you need high compensation pow-

er but lack the necessary indoor space

and cannot provide a large fenced-in

area for space reasons, BCOMP is the

right system for you. The use of indoor

components (e.g., iron core reactors), a

full-fledged outdoor system with a very

high power/weight ratio can be confi-

gured. All versions of the BCOMP series

follow a 2-space concept. The power

section (medium voltage components)

is spatially separated from the control/

operating section. Thus, access to the

control section is possible at any time

whereas the power components are pro-

tected by door lock and emergency stop

function. BCOMP systems find frequent

application on wind farms/solar parks or

large industrial facilities. The BCOMP

system is marketed as fixed step (-F), ex-

ternally controlled (-E) or automatically

controlled (-A) version. In addition to

standard reactors, the BCOMP system

can also be designed as customized filter

circuit system.

FEATURES

Turn-key overall concept

Ideal for limited outdoor areas

High power/weight ratio

Can be designed as multi-step filter

concept

F-90 fire resistant walls

Insulated roof

Optional forced ventilation and

air-conditioning equipment

Separate medium voltage and

control spaces

Low noise emission

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More interesting facts about resistance to moisture condensation: pages 24 to 27.

TECHNICAL SPECIFICATIONS – MIКA-BCOMP

Operating voltage

Control voltage

Nominal frequency

Insulation level

Power per step

Type series

Design versions

Tuned frequency

Protection

Ambient temperature

Installation site

Altitude


Norm

Finish


Optional

1 kV - 36 kV*

230 VAC / 220 VDC (fused)*

50 / 60 Hz

20 / 60 kV bis 70 / 170 kV

250 kvar to 5000 kvar*

Depending on the voltage level,

capacitor banks of the C series or the

E-/G series are installed

-F (fixed step)



189 Hz (7%)*

LINR inrush current limiting reactors

on request

– 20 °C to 40 °C*

Outdoor


Faradol / Jarylec

IEC 60871-1 / IEC 60071 / IEC 60282-1 / VDE 101

on request

on request

Control cabinet with position indicator, door lock

with discharge time monitoring, discharge

transformer, heating, ventilation, lighting,

voltage transformer, definite-time overcur-

rent-time protection, pressure relief flaps,

visualization system, link-up with process control

system, air-conditioning equipment, etc.



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MIКA-FILT


FILT

The MIКA FILT series is specially con-

figured solution for projects requiring

high power indoors and outdoors.

Medium voltage components, particu-

larly at voltages > 20 kV, often have a

large footprint area, maybe because

of the mechanical dimensions or the

required iron-free areas or the pre-

scribed safety distances. Therefore,

the IP00 version often is the most cost

effective or technologically the most

appropriate solution. Outdoor appli-

cations exclusively use air-core reac-

tors. Indoor systems also come with

iron-core reactor. Filter circuits of type

FILT are always specifically tailored to

the requirements in the customer’s

grid and are highly effective in such

grids due to their exact rating. Spe-

cial applications such as tele command

blocking filter or inductive compensa-

tion can also be provided.

FEATURES

Up to 110 kV

Ideal for applications requiring

high power > 5 Mvar

IP00 for indoor and outdoor installation

Air-core or iron-core reactors

Unbalance monitoring

Optional damping resistor

Optional phase current transformer

Optional system visualization and

DMC controller

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More interesting facts about air & iron: pages 24 to 27.

TECHNICAL SPECIFICATIONS – MIКA-FILT

Operating voltage

Control voltage

Nominal frequency

Insulation level

Nominal power

Type series

Design versions

Tuned frequency

Protection

Ambient temperature

Installation site

Altitude


Norm


Optional

1 kV - 36 kV*

230 VAC / 400 VAC / 220 VDC (fused)*

50 / 60 Hz

20 / 60 kV to 70 / 170 kV

250 kvar to 70 000 kvar*

G-/F- series (single-phase capacitors

with unbalance monitoring

-F (fixed step)



189 Hz (7 %)*

Filter application


IP23D - IP34D*

– 25 °C to 40 °C*

Outdoor


Faradol / Jarylec

IEC 60871-1 / IEC 60071 / IEC 60282-1 / VDE 101

on request

Stainless steel terminal box, discharge transfor-

mer, voltage transformer, definite-time overcur-

rent-time protection, damping resistors, outdoor

power breaker, grounding switch / breaker, DMC

controller, etc.



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GRID ANALYSIS

An ideal system design is very often based on detailed and explicit measu-

ring reports and grid analyses of the grid section for which compensation

/ filtering is required. The quality of these reports is very important. Pro-

founded measurements provide the

information for grid calculation and

form the basis of an adequate ap-

plication. Therefore, have your grid

analyzed by professional analyzers

and be sure that your system is opti-

mized for the grid conditions and for

your production processes. We will

be glad to submit our offer for a pro-

fessional analysis.

MIКA SERVICE

ENGINEERING

On the basis of a qualified measuring report and/or of clear customer requirements

and a couple of important marginal items of information (e.g., installation site, am-

bient conditions, application), our team tailors your system exactly to your needs.

The components can either be picked from our wide standard product portfolio, mo-

dified if necessary or designed individual-

ly to your specifications. The overriding

aspects for design and dimensioning are

excellent quality and long service life as

well as cost efficiency and profitability of

the system, guided by the principle: as

much as necessary, as little as possible.

Your system must match you and your

grid and the investment be returned as

quickly as possible.

MIКA® powered by Condensator Dominit

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COMMISSIONING

The moment your system is connected to grid is always an exciting moment also

because the system contains an enormous amount of energy. So, any mistake or

error can be the cause of dramatic damage. Therefore, it is of particular importance

that everything is checked meticulously before the system is connected to the grid.

We are anxious to be part of these preparations and monitor all activities. It goes

without saying that our systems undergo detailed checks before shipment from

the factory. All checks are documented extensively. However, defects may develop

during transport or on site. To detect and repair such defects before the system is

connected to the grid is essential. The-

refore, have your system checked by an

experienced Condensator Dominit en-

gineer before it is connected to the grid.

We suggest that a comparative measu-

rement should be made on this occasion

to document the state before installation

and after connection to the grid.

MIКA SERVICE

MAINTENANCE

Medium and high voltage systems from the MIКA product family are generally

very robust and designed for a long service life. Despite that, the components

are exposed to ageing. Besides, the grids in which the systems are installed

change and along with it the stress to

which the systems are exposed. So, re-

gular maintenance is necessary to ensu-

re the constant system availability. Con-

densator Dominit therefore recommend

customers to have their systems ser-

viced once a year. We will be glad to dis-

cuss this with you.


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Unbalance monitoringTechnologically, unbalance monitoring provides the best possible protection of capacitor systems. For this, the capacitor bank is connected as a double star (YY) and the equalizing current measured between the start points.The capacitors are arranged in perfectly symmetrical manner. As a result of this, both star points have the

same potential irrespective of the grid situation. However, every modifi-cation of a component in the capacitor disturbs the balance and gives rise to an equalizing current. Protection systems can be implemented ideally when the equalizing current is measured.Fuses and circuit breakers reduce the damage by failsafe components; unba-lance monitoring already prevents failure.

Inrush current limiting reactorsInrush current limiting chokes limit the current that is flo-wing the moment the capacitor is energized on. This has several advantages:• Reduces the grid side voltage drop during turn-on• Facilitates the design of the up-line power breaker• Easier compliance with selectivity criteria• Unproblematic parallel connection of several capaci-

tor banks• Reduces the inrush current (Î) according to norm < 100 x IN (IEC 60871)

Optimum ventilationOrganic polymers are used as dielectric in capacitors. The service life of these polymers depends strongly on the heat load to which they are exposed and the available cooling.Generally, an open design of the capacitor bank ensures optimum cooling without forced ventilation. However, high power capacitor banks, in particular, generate large amounts of heat, which suggests IP00 as design solution. All Condensator Do-minit capacitors are designed for an expected service life of 15 years, on aver-age.

KNOWLEDGE -PRESS

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Reactor factorCapacitors without reactor, in combination with the transformer or other inductive components of the po-wer supply grid, rise to resonance, which affects the grid quality. To prevent undefined / impermissible grid resonance by the compensation system, choked com-pensation units should be installed in modern industry

grids. The series connection of a reactor and the capacitor generates a defined minimum impedance of the compensation system. The tuned frequency is the result of the reactor factor, which is usually expressed in per cent.

Typical tuning frequences of deturned filter:• 7 % (189 Hz)• 12,5 % (141 Hz)• 14 % (134 Hz)

All compensation systems of the MIКA series are also available as filter circuit design.

Discharge time of capacitorsCapacitors are excellent energy storage devices. When a compensation system is turned off, it must be assumed that the capacitors are still be dischar-ged. This can be a safety risk to persons and when the compensation system is turned on again while the capacitors are still charged, this affects the life of the capacitors and therefore is not recommen-ded.• Unless explicitly agreed otherwise in the purchase order, all medi-

um voltage capacitors delivered by Condensator Dominit are equip-ped with an internal discharge device which ensures norm compliant discharge of the capacitor.

• The standard for medium voltage capacitor systems requires a dischar-ge to 75 V residual voltage within 10 minutes.

• All system controllers from Condensator Dominit ensure that the banks are not switched until the end of a appropriate discharge time.

• Conventional AC voltage testers cannot measure the discharge of a ca-pacitor reliably – Caution: Direct voltage (use a DC voltage tester).

fres = 12 ∏ √LC

p [%] =fn

fres( (

2x 100 %


26

Internal Faults, ArcingThe energy content of an internal faults arc, particularly in a medium voltage system, can be substantial.Generally, the damage an internal fault cau-ses is the greater the higher the voltage, the higher the short circuit power of the grid and

the longer the arc stands. If in a compensation plant the accidental arc occurs down-line the anti-resonance reactor, the arc current is distinctly smaller. The advantage of this is that generally the risk of accidental arcing in a compensati-on system is smaller than in switchgear, but that must be considered when the settings of up-line circuit breakers, if installed, are made.The energy content of an accidental arc that occurs for 1 second at a voltage of the order of 20 kV is equal to the explosive power of about 1 kg T N T for every 10 kA shirt-circuit current!!

IP protection classesThe protection of persons against acciden-tally touching a medium voltage system installed outdoors and for protecting the system from weather and trespassers are very important aspects. In the nomencla-ture of the IP protection class, the first digit describes the dust protection, the second digit describes the protection against the entry of water and in some cases an additional letter provides information about personal protection. Frequently used protection classes have the following meanings:• IP00 – no shock hazard protection, no protection from weather impact, com-

pletely open. Systems of this type must be protected by a fence or installed inside a hall.

• IP21 – protection against solid foreign objects of > 12 mm diameter and water drops from above; systems of this type are suitable, in the first line, for instal-lation in closed indoor equipment rooms.

• IP42 - protection solid foreign object of > 1 mm diameter and water hitting the equipment obliquely; potential installation sites include factory halls with sprinkler systems or outdoor sites.

• IP34D - protection solid foreign object of > 2.5 mm diameter and splash water from any direction; “D” means increased personal protection. A wire or tool entering the system 100 mm will not reach any part live with electricity.

KNOWLEDGE -PRESS

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Resistance to moisture condensationElectrical equipment in closed buildings or sta-tions is protected from direct exposure to we-ather.However, optimum ventilation is essential to the service life of compensation systems instal-led in indoor environments, which means that the equipment is exposed to indirect weather conditions. To resolve this contradiction, the concrete stations of Condensator Dominit consist of two parts.The control electronic component, programmable logic assemblies and other susceptible components are installed in a separate air-conditioned ca-binet or an air-conditioned compartment of the station.These components produce very little heat and air-conditioning is not a pro-blem technically.The actual power components come with double impregnation and other similar treatment to make them insensitive to weather.

Air an iron Iron core reactor are compact, rarely have a strong field, are ideal for indoor environments and provide high inductivities on a small footprint area. Air

reactors need iron-free space around them to avoid magnetic interfe-rence, are ideal for outdoor sites and are suitable, in particular, for high power levels.Typically, air core reactors should be used for applications of 20 kV or more and powers per step of 2.5 Mvar and more. Iron core reactors are generally preferred for voltages below 20 kV or less than 2.5 Mvar po-wer per step.

Condensator Dominit GmbH

An der Bremecke 8

D-59929 Brilon

Phone +49 (0) 2961 782-0

Fax +49 (0) 2961 782-36

E-Mail [email protected]

Web www.condensator-dominit.de

MEDIUM VOLTAGE COMPENSATION SYSTEMS · MEDIUM VOLTAGE CAPACITORS 05 Medium voltage compensation...

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Transcript of MEDIUM VOLTAGE COMPENSATION SYSTEMS · MEDIUM VOLTAGE CAPACITORS 05 Medium voltage compensation...