The ABB solution for active harmonic filtering

Power Quality FilterPQFA, PQFL

Harmonics caused by non-linear electrical loads such

as variable speed drives, rectifiers, UPS's, computers,

TV sets, … are a growing problem both for electricity

suppliers and users.

An example of a line current distortion due to a

variable speed drive is shown below.

The Power Quality Filter developed by ABB is an active

filter offering unprecedented ability to clean the

network from harmonics. The PQF eliminates

harmonics in a controlled way. It is easy to extend and

adapt to changes in the network.

The PQF monitors the line current in real time and

processes the measured harmonics as digital signals in

a high-power DSP (Digital Signal Processor). The output

of the DSP controls PWM (Pulse Width Modulated)

power modules that through line reactors inject

harmonic currents with exactly the opposite phase to

those that are to be filtered.

Harmonics can lead

to serious problems:

• overheating of cables, motors and transformers

• damage to sensitive equipment

• tripping of circuit breakers

• blowing of fuses

• premature ageing of the installation

Principle of operation

LOAD

Harmonics and Power Quality

The ABB Solution: PQF Power Quality Filter

Fundamental only

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Harmonicsonly

PQF

CT

Line current - Initial situation

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• May filter without generation of

reactive power

• May generate and control power factor

• Has programmable task priorities

• Does not require detailed network

analysis

• Does not require special CT's

• Is easy to extend on site

• Comes factory tested

• Filters up to 20 harmonics

simultaneously

• Filters up to the 50th harmonic

• Filters with closed loop control for best

accuracy

• Is not overloadable

• Has a programmable filtering strategy

and free choice of harmonics

As shown below, the net effect of the installation of a

PQF is an elimination of the harmonics and a clean

sine wave as seen by the feeding transformer.

The flexibility and accuracy of the PQF is due to a closed

loop control system incorporating additional

microprocessor capability in addition to the main DSP.

The overall performance and power of the concept

relies on optimally designed IGBT power modules used

to the particular needs of an active filter application.

The PQF is usually directly connected to the LV

network. Solutions for higher voltages are also

available.

Advantages of the PQF

PQF : The Ultimate Step in Filtering EfficiencyFIL

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Line current - Filter running

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PQFA

Digital Control (DSP)

• Programmable filtering

characteristics

• Perfect multi-tuning

to selected harmonics

• Not overloadable

• Programmable power

factor correction

• Zero-Q filtering capacity

• Programmable task

priorities

Power electronics

PWM converter

IGBT technology

Forced air cooling

Breaker & Auxiliaries

PQFL

Digital Control (DSP)

• Programmable filtering

characteristics

• Perfect multi-tuning

to selected harmonics

• Not overloadable

• Programmable power

factor correction

• Zero-Q filtering capacity

• Programmable task

priorities

Power electronics

PWM converter

IGBT technology

Forced air cooling

Contactor & fuses

Auxiliaries

PQFAThe PQFA consists of one controller and up to eight

power modules mounted in cubicles together with

auxiliary apparatus and wiring to form a factory

assembled and tested system.

The complete PQFA system consists of cubicle sections of

standard dimensions 800 x 2150 x 600 mm

(W x H x D). Large systems are usually mounted on a

base for a total height of 2350 mm.

Each cubicle section may contain:

A - One Controller and one power module (master unit)

B - One Controller and two power modules (master unit)

C - One power module (slave unit)

D - Two power modules (slave unit)

Each system consists of one master and up to three slave

sections. On site extensions are easily made by adding

cubicle sections to a maximum of 4 cubicles. Several PQFA

may operate together on the same network.

PQFLThe PQFL consists of one controller and one power

section mounted either in an IP23 cubicle or on a

common plate (plate execution IP00).

The cubicle version is factory assembled with auxiliary

apparatus and wiring. The plate execution is equipped

with a terminal for the connection of the wires to the

cubicle front door. All the accessories to be installed

on the front door are also supplied.

The standard dimensions of the cubicle are

600 x 600 x 2150 mm (W x D x H).

The standard dimensions of the mounting plate are

498 x 400 x 1896 mm (W x D x H).

The PQFL is extensible to a maximum of 4 power

sections of the same rating (1 master unit and 3 slave

units). Several PQFL may operate together on the same

network.

Description

Ratings and Capabilities

Power modules for the PQFA are available with voltage

ratings up to 600V for 50 or 60 Hz. The thermal rating

for one module is maximum 225 ARMS.

The PQFL is rated for 400V (415V) - 50Hz or 60Hz

networks. The thermal rating for one power section is

maximum 130 ARMS.

Solutions for other voltages are also available : PQFB for

voltages above 600V and PQFC for medium voltage

applications. Please consult us. The absolute harmonic filtering

capability depends on the content of higher harmonics with

the filtering capability following common load spectra.

Systems for 50 Hz may filter up to 20 harmonics

simultaneously up to the 50th harmonic. Systems for

60 Hz may filter up to 15 harmonics simultaneously

up to the 50th harmonic.

Individual harmonics may be chosen for filtering either

to zero or to a level defined in absolute or relative

terms.

Reactive power compensation may be chosen and

controlled to the desired power factor. The reactive

power compensation capacity per module is given by

the thermal rating.

The programming is made through an RS232 port using

standard PC equipment and software supplied with the

PQF. As an alternative, the programming may be

performed with the optional PQF-Manager or PQF-

Link.

CONTROL

POWERMODULE

AMaster

CONTROL

POWERMODULE

POWERMODULE

BMaster

POWERMODULE

POWERMODULE

DSlave

POWERMODULE

CSlave

CONTROL

POWERSECTION

Master

POWERSECTION

Slave

W

H

D

The PQF-Manager The PQF-Manager offers direct control, programming

and monitoring capability without using a

PC. It is located on the front panel of the filter

cubicle.

Optional accessories

Keyboard

160x80 pixelbacklit LCD

Indicator lights

RS-232 serial port(connection withcontrol rack)

Window selection

Access-key to the3-level menu

The PQF-Manager

Technical Specifications

Dimensions: 258 x 124 mm

Installation: As an option, on the front panel of the

filter cubicle.

Display: 160 x 80-pixel backlit LCD

MENUS

3 main menus are available

according to the priority level

of the user:

•Consulting level (default

level)

•Filter operation

•Hardware set-up

Consulting levelIn the consulting level, the

PQF-Manager displays the

following information:

- Filter status

• Percentage of filter capability

used (DC voltage, peak and

RMS currents)

• Error messages

- Network status

• Line voltages (L1-L2, L2-L3, L3-L1)

• Line currents (L1, L2, L3)

• Voltage THD (L1, L2, L3)

• Current THD (L1, L2, L3)

- Waveform

• Line voltages (L1-L2, L2-L3, L3-L1)

• Line currents (L1, L2, L3)

• Filter currents (L1, L2, L3)

- Spectrum

The spectrum of any of the

mentioned waveforms is available.

The values indicated may be

expressed in Amps or in Volts.

Filter operationMode

The basic operation is to filter

to a prescribed level. The

function Mode allows using the

additional capabilities of the

filter for maximum filtering

(harmonics close to zero) or for

generation of reactive power.

Reactive power

Reactive power compensation

functionality may be selected. If

fixed compensation is chosen,

then the output power needs to

be set. If dynamic compensation

is chosen, then the desired target

power factor needs to be set.

Harmonics

The frequency components to

actively filter may be freely

selectable. The degree of filtering

may be specified per component

in Amps or as a percentage of the

fundamental or total RMS current.

Hardware set-upThis level gives access to

hardware configuration

parameters: network

characteristics, filter sensors,

and filter hardware set-up.

ACCESSPROTECTIONFilter operation and hardware

set-up are password protected.

In order to increase safety, the

priority level automatically goes

down to the lowest level after

one minute of non-use of the

PQF-Manager.

The PQF-Link

The PQF-Link software offers direct control,

programming and monitoring capability from a PC

through the RS-232 serial port.

All the features of the PQF-Link are directly

accessible by clicking on the icons of the shortcut

menu.

According to the login level of the user, different

icons are displayed.

3 access levels are defined in the login procedure:

•Consulting level: default level – access to filter

and network status, to waveform and spectrum

display

•Filter operation: access to consulting level and

filter programming

•Hardware set-up: access to filter operation and

hardware set-up

Particular features include:

• Detailed information on filter status:

• % of filter capability used

• error history

• Advanced spectrum display: bar graph and

table of values in the same window:

• line voltages

• line currents

• filter currents

• Display of the filter and network waveforms

with a customised time base:

• Line voltages

• Line currents

• Filter currents

• Simultaneous waveform display for the 3

phases

• Continuous updating of displayed information

or snapshot display

• Remote control and programming of the PQF

• On/off

• Mode selection

• Reactive power control

• Harmonics and reactive power specifications

• Remote hardware set-up

• Network characteristics

• Filter sensors

• Filter hardware

• Display of several windows simultaneously

• Add/remove users and define their access level

The PQF-Link works under Windows NT®,

Windows 95® or Windows 98®.

A cable for PC connection is supplied with the PQF-Link.

Line current spectrum and

waveform (3 phases)

displayed simulteanously

Simultaneous display of

several windows

PQFL PQFARMS current per module

50 Hz - 400V (415V) 70A, 100A or 130A / power section 225A / power module- 525V - 165A / power module

60 Hz - 440V - 170A / power module- 480V - 155A / power module- 600V - 110A / power module

Other voltages and ratings on request Other voltages and ratings on requestModularity(*) up to 4 power sections / system up to 8 power modules / systemPhysical mounting 1 power section / cubicle up to 2 power modules / cubicleVoltage tolerance +/- 10% +/- 10%Harmonics to filter 50 Hz: up to 20, programmable up to the 50th harmonic up to 20, programmable up to the 50th harmonic

60 Hz: up to 15, programmable up to the 50th harmonic up to 15, programmable up to the 50th harmonicDegree of filtering Individually programmable per harmonic Individually programmable per harmonic

in relative or absolute terms in relative or absolute termsTypical filtering efficiency Better than 97% Better than 97%Reactive power Power factor programmable Power factor programmable

from 0.7 inductive to 0.7 capacitive from 0.7 inductive to 0.7 capacitiveCommunication RS232 port RS232 portProgramming Alt 1) Using PC (not provided) and software supplied with the equipment Using PC (not provided) and software supplied with the equipment

Alt 2) Using optional PQF-Manager Using optional PQF-ManagerAlt 3) Using PC (not provided) and optional PQF-Link software Using PC (not provided) and optional PQF-Link software

Response time 40 ms 40 msActive power less than 3 kW per module at full load less than 7 kW per module at full loadProtection IP23 (IP20 open door) - Plate execution IP00 IP23 (IP20 open door)Cubicle dimensions 600 x 600 x 2150 mm (W x D x H) 800 x 600 x 2150 mm (W x D x H)Plate dimensions 498 x 400 x 1896 mm (W x D x H) -Weight Appr. 250 kg (IP00 : appr. 200 kg) Appr. 600 kg (with two power modules)Colour RAL 7032 (Beige) RAL 7032 (Beige)

Installation PQFA & PQFL IP23: Floor fixation. Lifting lugs provided. Cable entry from the bottom.PQFL IP00: plate to be mounted in cubicle (not provided)

Environment Indoor installation in clean environment up to 1000m altitudeAmbient temperature -10°C/+40°C Humidity Maximum 95% RH; non-condensingOptions Socle (200 mm)

Current transformers (ratings and dimensions to specify)Voltage-free alarm contactPQF-ManagerPQF-Link

(*) A derating of 5% should be considered for systems with more than one power module / section.S

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Technical specifications

Connection diagram

X5.1 X5.2 X5.3 X5.4 X5.5 X5.6 L1 L2 L3

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CT x/5ACT x/5A

CT x/5A

P.E.

SUPPLY LOAD(S)

PQF

Active filter for connection between the three phases of a three-phase network with or without neutral for

filtering of non zero-sequence harmonics and optional reactive power compensation.

While all care has been taken to ensure that the information contained in this publication is correct,

no responsibility can be accepted for any inaccuracy. The Company reserves the right to alter or modify

the information contained herein at any time in the light of technical or other developments. Technical

specifications are valid under normal operating conditions only. The Company does not accept any

responsibility for any misuse of the product and cannot be held liable for indirect or consequential damages.