ABB PQFA User manual

Instructions Manual PQFA

Power Quality Filter

ABB Jumet

PQFA Instructions Manual

__________________________________________________________________________

Asea Brown Boveri Jumet S.A.

2

Table of contents

1. SAFETY INSTRUCTIONS...................................................................................................................5

2. UPON RECEPTION ............................................................................................................................6

2.1. DELIVERY INSPECTION........................................................................................................................6

2.2. IDENTIFICATION TAG...........................................................................................................................6

2.3. STORAGE..........................................................................................................................................6

2.4. LONG STORAGE PERIOD AND REFORMING .............................................................................................6

3. PQFA PRINCIPLE AND CHARACTERISTICS....................................................................................7

3.1. REASONS FOR LIMITING HARMONICS .................................................................................................... 7

3.2. GENERAL PRINCIPLE OF ACTIVE FILTERING............................................................................................8

3.3. THE ABB ACTIVE FILTER: THE PQFA. .................................................................................................9

3.4. THE PQFA: PERFORMANCES............................................................................................................11

3.4.1. Filtering.................................................................................................................................11

3.4.2. Reactive power......................................................................................................................12

3.4.3. EMC......................................................................................................................................12

4. COMPONENTS DESCRIPTION AND IDENTIFICATION...................................................................13

4.1. COMPONENTS DESCRIPTION .............................................................................................................13

4.1.1. PQF current generator...........................................................................................................13

4.1.2. The control............................................................................................................................14

4.2. COMPONENTS IDENTIFICATION ..........................................................................................................15

5. MECHANICAL INSTALLATION........................................................................................................26

6. ELECTRICAL INSTALLATION .........................................................................................................29

6.1. OVERVOLTAGE ................................................................................................................................29

6.2. POWER CABLES AND EXTERNAL PROTECTION......................................................................................29

6.3. CURRENT TRANSFORMERS/CONTROL CABLES SELECTION.....................................................................32

6.4. CURRENT TRANSFORMERS INSTALLATION...........................................................................................34

6.4.1. CT’s connection to the PQFA.................................................................................................34

6.4.2. CT’s connection topology: cases............................................................................................36

6.4.2.1. Case 1: Global compensation – one feeding transformer........................................................................36

6.4.2.2. Case 2: Individual compensation – one feeding transformer...................................................................37

6.4.2.3. Case 3: global compensation – transformer busbar not accessible........................................................38

6.4.2.4. Case 4: two independent feeding transformers........................................................................................40

6.4.2.5. Case 5: back up generator.........................................................................................................................42

6.5. PRECAUTIONS WITH CAPACITORS ......................................................................................................43

7. CUBICLES INTERCONNECTIONS...................................................................................................44

7.1. INTRODUCTION ................................................................................................................................44

7.2. MECHANICAL INSTALLATION ..............................................................................................................44

7.3. ELECTRICAL CONNECTIONS...............................................................................................................45

7.3.1. Connections between cubicles...............................................................................................45

7.3.1.1. Power connection........................................................................................................................................45

7.3.1.2. Control connection......................................................................................................................................46

7.3.1.3. Domino boards connection.........................................................................................................................47

7.3.1.4. Earth connection.........................................................................................................................................48

7.3.2. Connections to the supply......................................................................................................48

7.3.2.1. Power connection........................................................................................................................................48

7.3.2.2. Protective earth...........................................................................................................................................48

8. PQF-PROG INSTALLATION AND PC CONNECTION ......................................................................50

8.1. SYSTEM REQUIREMENTS...................................................................................................................50

8.2. INSTALLING PQF-PROG ON YOUR PC................................................................................................50

PQFA Instructions Manual

__________________________________________________________________________

Asea Brown Boveri Jumet S.A.

3

HARDWARE CONNECTION..............................................................................................................................50

9. COMMISSIONING.............................................................................................................................51

9.1. STEP 1...........................................................................................................................................51

9.2. STEP 2...........................................................................................................................................51

9.3. STEP 3...........................................................................................................................................52

9.3.1. PQF connection diagram.......................................................................................................52

9.3.2. Material needed & hypotheses for correct measurements......................................................53

9.3.3. Checking the correct connection of the CTs with a two channel scopemeter...........................53

9.3.3.1. Measurement of CT in phase L1................................................................................................................53

9.3.3.2. Measurement of CT in phase L2 and L3...................................................................................................55

9.3.4. Checking the correct connection of the CTs with two current probes......................................56

9.3.5. Checking the correct connection of the CTs with a Fluke 41B.................................................56

9.4. STEP 4...........................................................................................................................................57

9.4.1. With PQF-Prog......................................................................................................................57

9.4.2. With the PQF-Manager..........................................................................................................58

9.5. STEP 5...........................................................................................................................................59

9.6. STEP 6...........................................................................................................................................59

9.7. STEP 7...........................................................................................................................................59

9.8. STEP 8...........................................................................................................................................59

10. OPERATION.....................................................................................................................................61

10.1. NORMAL WORKING SEQUENCE ..........................................................................................................61

10.2. OPERATION WITH CAPACITORS..........................................................................................................66

10.3. BEHAVIOR IN CASE OF POWER OUTAGE ..............................................................................................66

10.4. BUTTONS, LIGHTS AND LED’S SIGNIFICATION......................................................................................67

10.4.1. Master cubicle.......................................................................................................................67

10.4.2. Slave cubicle.........................................................................................................................67

10.4.3. PQF-Manager........................................................................................................................68

10.4.4. Control rack...........................................................................................................................69

10.5. PROGRAMMING WITH PQF-PROG......................................................................................................70

10.5.1. Filter operation principle.........................................................................................................70

10.5.2. Starting..................................................................................................................................71

10.5.3. Programming the filter............................................................................................................73

10.6. PROGRAMMING WITH PQF-MANAGER................................................................................................75

10.6.1. Filter operation principle.........................................................................................................75

Keys identification..............................................................................................................................76

10.6.3. Programming the filter............................................................................................................77

10.7. PQFA AND NETWORK MONITORING WITH THE PQF-MANAGER..............................................................81

10.7.1. Filter status............................................................................................................................81

10.7.2. Network status.......................................................................................................................82

10.7.3. Waveform..............................................................................................................................83

10.7.4. Spectrum...............................................................................................................................84

10.8. REMOTE CONTROL AND ALARM CONTACT............................................................................................85

10.8.1. Remote control......................................................................................................................85

10.8.2. Alarm contact.........................................................................................................................86

10.9. PROTECTIONS .................................................................................................................................86

11. FAULT HANDLING AND TROUBLESHOOTING ..............................................................................88

11.1. FAULT HANDLING .............................................................................................................................88

11.1.1. Type of faults.........................................................................................................................88

11.1.2. Fault handling and fault clearance procedure.........................................................................88

11.2. TROUBLESHOOTING .........................................................................................................................91

11.2.1. Frequent problems occurring at commissioning stage............................................................91

11.2.2. Error codes meaning..............................................................................................................91

11.2.3. Faults not related to error codes.............................................................................................95

11.2.4. Restarting the filter after fault correction.................................................................................95

PQFA Instructions Manual

__________________________________________________________________________

Asea Brown Boveri Jumet S.A.

4

12. MAINTENANCE................................................................................................................................96

12.1. MAINTENANCE FREQUENCY...............................................................................................................96

12.2. MAINTENANCE PROCEDURE ..............................................................................................................96

12.3. FAN................................................................................................................................................97

12.4. CAPACITORS REFORMING .................................................................................................................97

PQFA Instructions Manual

Asea Brown Boveri Jumet S.A.

5

1. Safety instructions

These safety instructions are intended for all work on the PQFA.

Neglecting these instructions can cause physical injury and death.

All electrical installation and maintenance work on the PQFA should be

carried out by qualified electricians.

Do not attempt to work on a powered PQFA.

After switching off the mains, always wait at least 5 minutes before

working on the unit in order to allow the discharge of DC capacitors

through the discharge resistors.

DC capacitors might be charged to more than 1000V.

Before manipulating current transformers, make sure that the secondary

is short-circuited. Never open the secondary of a loaded current

transformer.

You must always wear isolating gloves and eye-protection when

working on electrical installation. Also make sure that all local safety

regulations are fulfilled.

PQFA Instructions Manual

Asea Brown Boveri Jumet S.A.

6

2. Upon reception

2.1. Delivery inspection

Each PQFA is delivered in a sealed package designed to protect adequately

the equipment during shipment.

Upon receipt of the equipment, make sure that the packing is in good

condition.

After removal of the packing, check visually the exterior and interior of your

filter. Any loss or damage should be notified immediately.

Care should be taken to ensure that correct handling facilities are used.

2.2. Identification tag

Each PQFA is fitted with a nameplate for identification purposes. The

nameplate includes the type of filter, nominal frequency, voltage and current

as well as a serial number and an ABB internal article code.

This information should always remain readable to ensure proper identification

during the whole life of the filter.

2.3. Storage

PQFA packing is made for a storage period of maximum six months (transport

time included from delivery date EXW ABB Jumet factory). Packing for longer

storage period can be done on request.

If your PQFA is not installed once unpacked, it should be stored in a clean

indoor, dry, dust free and non-corrosive environment. The storage

temperature must be between –15°C and 70°C with a maximum relative

humidity of 95%, non-condensing.

Before installing and operating your PQFA, you should read very carefully this

instructions manual and you should make sure that the information given on

the nameplate corresponds to your network.

2.4. Long storage period and reforming

If your PQFA is non-operational or stored for more than one year, the DC

capacitors need to be reformed (re-aged). Without reforming, capacitors may

be damaged when the filter starts to operate.

The reforming methods are described in chapter 12 (maintenance).

PQFA Instructions Manual

Asea Brown Boveri Jumet S.A.

7

3. PQFA principle and characteristics

3.1. Reasons for limiting harmonics

Power electronics based equipment is the main source of the harmonic

pollution in electric networks. Examples of such equipment include drives (AC

or DC), UPS’s, welders, PCs, printers etc.

In general, the semiconductor switches in this equipment conduct only during

a fraction of the fundamental period. This is how such equipment can obtain

their main properties regarding energy saving, dynamic performance and

flexibility of control. However, as a result a discontinuous current containing a

considerable amount of distortion is drawn from the supply.

Harmonic pollution causes a number of problems. A first effect is the increase

of the RMS-value and the peak-value of the distorted waveform. This is

illustrated in figure 3.1. that shows the increase of these values as more

harmonic components are added to an initially undistorted waveform. The

RMS-value and the peak-value of the undistorted waveform are defined as

100 %. The peaks of the fundamental component and the distortion

components are assumed to be aligned. It may be seen that the distorted

waveform, which contains harmonics up to the 25th harmonic, has a peak

value that is twice the value of the undistorted waveform and a RMS-value

that is 10 % higher.

Peak: 100 % 133 % 168 % 204 %

RMS: 100 % 105 % 108 % 110 %

Figure 3.1. Evolution of the increase in peak-value and the RMS-value of

a waveform as more harmonic components are added

The increase in RMS-value leads to increased heating of the electrical

equipment. Furthermore, circuit breakers may trip due to higher thermal or

instantaneous levels. Also, fuses may blow and capacitors may be damaged.

kWh meters may give faulty readings. The winding and iron losses of motors

increase and they may experience perturbing torques on the shaft. Sensitive

electronic equipment may be damaged. Equipment, which uses the supply

voltage as a reference may not be able to synchronise properly and either

applies wrong firing, pulses to switching elements or switch off. Interference

with electronic communications equipment may occur.

100 % H1

+ 33 % H3

+ 20 % H5

… + 4 %

H25

PQFA Instructions Manual

Asea Brown Boveri Jumet S.A.

8

Distorted networks may also cause generators malfunctions.

Overall it may be concluded that an excessive amount of harmonics leads to a

premature ageing of the electrical installation. This is an important motivation

for taking action against harmonics.

3.2. General principle of active filtering

The active filter measures the harmonic currents and generates actively a

harmonic current spectrum in opposite phase to the measured distorting

harmonic current. The original harmonics are thereby cancelled. The principle

is shown in figure 3.2.

Figure 3.2. Principle of active filtering

The control of the active filter in combination with the active generation of the

compensating current allows for a concept that may not be overloaded.

Harmonic currents exceeding the capacity of the active filter will remain on the

network, but the filter will operate and eliminate all harmonic currents up to its

capacity.

The principle of active filter showing currents and spectra is clarified in Figure

3.3.

PQFA

Supply

Load

Fundamental only

-1.3

1.3

0 360

-1.3

1.3

0 360

-1.3

1.3

0 360

i

distortion

i

compensation

PQFA Instructions Manual

Asea Brown Boveri Jumet S.A.

9

Figure 3.3. Active filter principle illustrated in time and frequency

domains

3.3. The ABB Active filter: the PQFA.

As we have just seen, the active filter is basically a compensating current

generator. The most important parts are then the current generator and the

control system.

The compensating current is in a first step created by a three-phase Insulated

Gate Bipolar Transistors (IGBT) inverter bridge that is able to generate any

given voltage waveform with PWM (Pulse Width Modulation) technology. The

IGBT bridge uses a DC voltage source realised in the form of a DC capacitor.

The inverter bridge is in fact the same technology than in AC drives.

The generated voltage is coupled to the network via reactors and a small filter

circuit. The desired current generator is thereby achieved.

The DC capacitors are loaded actively through the inverter bridge and there is

no need of external power source. Obviously, the DC voltage level must

always be higher than the peak value of the network voltage in order to be

able to inject currents to the network.

To control the active filter the choice stands between open loop and closed

loop current control. Under open loop current control, the harmonics currents

are measured on the load side of the active filter that computes the required

compensating current and injects it into the network.

Closed loop current control as performed by the PQFA is shown in Figure 3.4.

In this topology the resulting current to the network is measured and the

active filter operates by injecting a compensating current minimising this

resulting current. In this configuration, the filter directly controls its effect on

the filtration.

+=

Load

current

1 5 7 11 13 17 19

-20

0

20

40

1 5 7 11 13 17 19

Active Filter

current

1 5 7 11 13 17 19

-20

0

20

40

1 5 7 11 13 17 19

Clean

feeder

current

1 5 7 11 13 17 19

-20

0

20

40

1 5 7 11 13 17 19

WaveformsHarmonics

-1.3

1.3

0 360

-1.3

1.3

0 360

-1.3

1.3

0 360

PQFA Instructions Manual

Asea Brown Boveri Jumet S.A.

10

Figure 3.4. Closed loop control

In addition to being more precise, the closed loop control system also allows

for a direct control of the degree of filtering. Furthermore, the closed loop

control system ensures that measurement errors do not result in a higher

distortion.

To fully exploit the potential of an active filter we need a digital measurement

and control system that is fast enough to operate in true real time. We need to

be able to track the individual harmonics and control the compensating

current according to the requirements of the plant and this with full control at

every instant in time. To achieve this, we need advanced Digital Signal

Processors, DSP’s.

Among the physical signals needed by the PQFA, the three line currents have

obviously to be measured. Standard CTs with 5A secondary are usually

sufficient. Those analogue signals must first be acquired, levelled and

antialias-filtered before digitalisation. Fast and high precision analogue-to-

digital converters are used to create a digital representation of the analogue

signals. The digitised signals are then sent to the powerful DSP that controls

all measurements and calculations in real time, and builds the PWM

references for the inverter. It is another processor, a microcontroller, which

handles all digital input/output (including the command of the PWM inverter).

More dedicated to control than to calculations, this microcontroller ensures for

instance the closing of the relays and contactors.

One control is needed per PQFA system and can handle more than one

power module simultaneously.

Control

AF

Target

Measurement Feedback

Output

PQFA Instructions Manual

Asea Brown Boveri Jumet S.A.

11

3.4. The PQFA: performances

3.4.1. Filtering

The main requirement for an active filter installed in an industrial installation is

to attenuate the harmonics produced by the non-linear loads of the

installation.

The ideal active filter should allow the user to choose freely which harmonic

components to filter and should offer an adjustable degree of filtering.

It is also worth noting that the total harmonic voltage distortion at the point of

common coupling (PCC) is often calculated up to the 40

th

[1] or the 50

th

[2]

harmonic. Furthermore, the total number of harmonics that can be filtered

determines directly the quality of the resulting current. This is illustrated in

figure 3.5., which shows the filtered waveforms obtained by filtering up to

different harmonic levels.

(a) Filtering up to the 13

th

harmonic.

(b) Filtering up to the 25

th

harmonic.

(c) Filtering up to the 50

th

harmonic.

Figure 3.5. Waveforms obtained by eliminating the harmonic

components of a rectangular periodic signal up to the (a) 13

th

harmonic,

(b) the 25

th

harmonic and (c) the 50

th

harmonic

This figure highlights the need for an active filter that can operate up to

sufficiently high harmonic frequencies.

The PQFA can filter simultaneously 20 (15) independent harmonics up to the

50

th

for 50Hz (60Hz) based networks. The number of harmonics to be filtered

as well as their frequencies is completely programmable by the user.

PQFA Instructions Manual

Asea Brown Boveri Jumet S.A.

12

Besides the harmonic selection functionality, the user has also the possibility

to specify a filtration level for each selected harmonic. The PQFA will filter the

selected harmonics until

by the user and may be different for each selected harmonic. This

functionality is especially useful when the objective is to fulfil the requirements

of a standard and results in a better use of the available compensation power.

It also allows the installation of active filters on networks already fitted with a

fixed passive filter.

We can see that we are very close to the ideal filter: the choice of which

harmonic components to filter is free and the degree of filtering is adjustable

according to the wishes of the user.

Moreover, all typical harmonics generated by three-phase non-linear loads

may be filtered simultaneously.

3.4.2. Reactive power

Besides the filtering functionality, reactive power compensation is also

possible with the active filter. Compared to traditional capacitor banks, the

reactive compensation of the PQFA is continuous (‘stepless’), fast and

smooth (no transients at switching). The compensation can be either

capacitive or inductive.

Two types of compensation are available: automatic compensation where a

target power factor has to be set, and fixed compensation based on a

predefined amount of kvar.

3.4.3. EMC

The PQFA has been verified for compliance with EU (European Union)

directives for EMC (electromagnetic compatibility) for operation at 50 Hz and

bears the CE-mark to this effect.

When an apparatus is used in a system, EU directives may require that the

system is verified for EMC compliance.

PQFA Instructions Manual

Asea Brown Boveri Jumet S.A.

13

4. Components description and identification

4.1. Components description

As already explained, the active filter is basically composed of two parts: the

current generator and the control system.

4.1.1. PQF current generator.

The power circuit of the ABB active filter PQF is represented hereafter.

Output

Filter

PWM inverter

Main Breaker

Power

Lines

+

-

PWM Reactors

Preload

The main components are:

- PWM inverter

- PWM reactors

- Output filer

- Preloading circuit

The current generator is physically organised in power modules, each

including a PWM inverter, three PWM reactors and the output filter.

Each PQFA cubicle may contain one or two power modules. There is one

breaker and one preloading circuit per cubicle.

Non-linear load(s)

(three-

phase or

single-phase)

PQF Digital

Control

Compensation

current

Current

measurement

PQF current

generator

PQFA Instructions Manual

Asea Brown Boveri Jumet S.A.

14

The PWM inverter is composed of DC capacitors and an IGBT inverter bridge.

This system is able to generate any voltage waveform with PWM technology.

The physical layout of a PWM inverter module is shown hereafter. Each PWM

inverter is fitted with a local electronic control called the domino board. The

domino board is controlled by the central DSP. The domino board is fitted with

jumpers noted JP100, JP101, JP102, JP103, JP104, JP105, JP106, JP109

and JP110 (JP107 and JP108 are off). In case of several power modules, only

the domino board of the last slave is fitted with jumpers.

The PWM reactors convert the voltage created by the PWM inverter into

currents that will be injected in the network.

The output filter consists in line reactors and an RC shunt circuit.

The function of the preloading circuit is to avoid at start-up high inrush

currents that could damage the power electronics or create transients in the

network.

4.1.2. The control

For best performances, the control of the PQFA is Digital Signal Processor

(DSP) based.

The three lines currents are measured by external CT. Those analogue

signals must first be acquired, levelled and antialias-filtered before

digitalisation. Fast and high precision anlogue-to-digital converters are used to

create a digital representation of the analogue signals. The digitised signals

are then sent to the powerful DSP that controls all measurements and

DC capacitors

Low inductance

DC bus bar

Inverter

Heatsink

PQFA Instructions Manual

Asea Brown Boveri Jumet S.A.

15

calculation in real time, and builds the PWM references for the inverter. It is

another processor, a microcontroller, which handles all digital input/output

(including the command of the PWM inverter). More dedicated to control than

to calculations, this microcontroller ensures for instance the closing of relays

and contactors.

One control unit may command up to 8 power modules.

4.2. Components identification

Control

PWM

inverter

module 2

PWM

inverter

module 1

Domino

board

Circuit

breaker

Fan

Output

filter

capacitor

Auxiliary

voltage

transformer

PQF

Manager

PQFA Instructions Manual

Asea Brown Boveri Jumet S.A.

16

A more detailed identification is given in the following pages.

The identification hereafter is related to the drawings of the following pages.

Internal views indicate the position of identified components but fixation

details are not included. Although visible on the drawings, some components

may actually be hidden in the real structure.

Mains power breaker

Q11: power breaker

L1, L2, L3: power cables connection

K102: contactor closing MCB

K103: contactor opening MCB

X8: terminal Sace wiring

Fan

M101: fan motor

K101: fan contactor

X9: terminal block motor connection wiring

F101: motor overload protection

Auxiliaries

Q101: breaker for auxiliaries

T101: auxiliary voltage transformer

PWM inverter

U11: module 1

U21: module 2

A117: module 1 domino board

A118: module 2 domino board

Output filter

C11_12_13A/B Module 1 output filter capacitor

C21_22_23A/B Module 2 output filter capacitor

X14 Terminal block capacitors module 1 wiring

X15 Terminal block capacitors module 2 wiring

R11/12/13 Module 1 output filter resistor

R21/22/23 Module 2 output filter resistor

L11/12/13 Module 1 line reactors

L21/22/23 Module 2 line reactors

PWM reactors

L14/15/16 Module 1 PWM reactors

L24/25/26 Module 2 PWM reactors

PQFA Instructions Manual

Asea Brown Boveri Jumet S.A.

17

Preloading circuit

K11 Preload contactor

R14/15 Preload resistor

U1 Preload bridge

Control rack

A111 Digital I/O board

A112 Interface board – IGBT’s and DSP

A113 Digital Signal Processor

A119 Interface PQF Manager board

A114 Current input board

A115 Analog input board

A116 +24V power supply board

U100 Power supply ? 15V

U109 Power supply + 5V

X1 Terminal block digital I/O wiring

X4 Terminal block current input wiring

X2 Terminal block analog input wiring

X10 Terminal power supply wiring

X6 Terminal current input wiring

A67 AC voltage board

Door components

S102 RESET push button

S101 RUN push button

S104 Remote local switch

H101 White lamp: controller connected to supply (auxiliary

breaker closed)

H102 Red lamp: MCB closed

H103 Green lamp: MCB open

A120 PQF-Manager

Other components

B101/102/103 Internal current sensors

K104 Alarm contactor

K12 Remote contactor

X5 Terminal block backplane wiring (external CT connection)

PQFA Instructions Manual

Asea Brown Boveri Jumet S.A.

18

X10 Terminal power supply wiring

X11 Terminal DC bus wiring

X12 Terminal signaling wiring

X13 Terminal inter cubicles wiring

A104 DC voltage convertor

PQFA Instructions Manual

Asea Brown Boveri Jumet S.A.

19

Master cubicle view

Zoom on next page

PQFA Instructions Manual

Asea Brown Boveri Jumet S.A.

20

Page is loading ...

ABB PQFA User manual

Related papers

Other documents