Voltage Regulator

WALCHER GmbH & Co.KG Kraftwerks-, Automatisierungstechnik, Energiemanagement,TransformatorenbauZum Lingeshof 3 D 36124 Eichenzell Tel. +49 (0) 6659 98794-0 Fax. +49 (0) 6659 98794-44

[email protected] http://www.walcher.com

Aggravation with voltage?At photovoltaic plants, long linesor increasing energy consumption?

...then the voltage regulator can help

Regulation of each single phase

Higher capacities on request

Quick regulation from 300-700 ms

34 till 300 kVA

F:/P

rosp

ekt

e/N

etz

regle

r/englis

ch/2

011

Voltage Regulator



8V

230V

8V

230V

8V

230V

8V

230V

8V

230V

8V

230V

Input Output

L

N

230 5V

0,3 0,5 1 1,5 2 3 km

70

60

50

40

30

20

10

kW Three-phase four-wire system 400/231V

50mm

²35mm

²25mm

²16mm

²

Please request our materials,we will gladly assist you.

The Voltage Regulator measures and regulates the three phases individually, quickly and independent of one another.

When idle or with an unloaded Voltage Regulator, the transformer stages that are not needed are bypassed. If the output voltage of the Voltage Regulator sinks below 225 volts due to load in the power supply lines, the required number of transformer stages in the affected phase are calculated and activated via the switch protectors. The bypass of the transformer stages to be switched is cancelled and the 230 volt winding is switched to the regulated line voltage.

With excessive input voltage, which can occur due to starpoint shifts especially under load, the Voltage Regulator can regulate the voltage upwards by polarizing the windings, whereby a symmetrical output voltage between 235 and 225 V / phase is always guaranteed.

This diagram depicts four common copper cross sections. The intersection with the km line provides the greatest possible performance for a range of +- 36V / phase, with which a complete regulation of the line voltage still occurs.

Example: for voltage regulator +- 36V/ Phase

Copper cross section q = 25mm²

Line length l = 1 kmIntersection produces P = 31kW



20

kV

0,4

kV

240m NAYY 4*120mm² 180m NAYY 4*120mm² 1230m NAYY 4*185mm²

line voltageregulator

Imax 100A

150A

30A

20A

100A

180V250 500 750 1500

200V

190V

m

210V

240V

230V

220V

voltage characteristics without line voltage regulator

voltage characteristics with line voltage regulator

line voltage regulator control range +- 5 V

Adjustment of a spur linevia a 69 kVA line voltage regulator

Application of a line voltage regulator (blue curve).The voltage shape without line voltage regulator is shown in the red curve.Due to the voltage increase after the line voltage regulator, the current before the line voltage regulator has to be higher, according to the power balance chart before and after the line voltage regulator (P = constant = U*I), which results in a slight additional voltage drop in the line.

3 p

hase

measu

rem

ent befo

re the v

olta

ge r

egula

tor:

measu

rem

ent in

5 m

in.

ave

rage v

alu

es

Regula

ted v

olta

ge a

fter

the

volta

ge r

egula

tor:

measu

rem

ent in

5 m

in a

vera

ge v

alu

es

U a

vera

ge L

1 [V

]U

ave

rage L

2 [V

]U

ave

rage L

3 [V

]

tim

e

Reco

rdin

g o

f th

e m

in. u. m

ax.

valu

es,

10 m

s sa

mplin

g

Befo

re the v

olta

ge r

egula

tor

After

the v

olta

ge r

egula

tor

Volta

ge d

rops

smalle

r 200 m

s ca

n n

ot

be r

egula

ted b

y th

e v

olta

ge r

egula

tor

U m

in L

1[V

]U

max

L1[ V

]U

min

L2 [V

]U

max

L2 [V

]U

min

L3 [V

]U

max

L3 [V

]

tim

e



180V250 500 750 1500

200V

190V

m

210V

240V

230V

220V

voltage characteristicswith 950V - transformers

voltage characteristicswith line voltage regulator

line voltage regulator control range +- 5 V

20kV

20kV

0,4

kV0,4

kV

240m NAYY 4*120mm² 1230m NAYY 4*120mm²

line voltageregulator

Imax 100 A

Imax 100 A42 A

120 A170 A

150 A

400 V

400 V

950 V

950 V

A

A

B

B

Voltage shape with a tail

with a line voltage regulator or 950 V transformers

As can clearly be seen from the comparison of the two variations A and B, the voltage support with two 950V transformers only offers a conditional solution, as the voltage drop is only reduced by 58%.

The solution via line voltage regulators, in contrast, enables a complete adjustment of the respective phase.



In the above diagram the transmission losses of the conventional networks for spur lines were compared with each other.

To serve as an example, a 1500m NAYY line of 150 mm² as taken as a basis for the calculations. The curves for the solution ”20kV transformer” take on the shape of scissor blades, as the 400V line length after the transformer considerably influences the transmission losses.

Result: In general, the line voltage regulator is the most profitable transmission type for spur lines up to approx. 900 - 1000 hours of use.

In comparison with the occasionally used 950 V version, the crossing of the two systems only appears after a service period of approx. 1800 hours which clearly is beneficial to the line voltage regulator.

Profitability

2000

0

5000

1000

6000

7000

8000

9000

4000

hours of use

10000

11000kWh

3000

200400

1400600

1600800

18001000

20002200

12002400 h

950V conduction

68 k

VA line

volta

ge re

gulato

r

20kV transformer

0,4

KV

lin

e length

20kV transform

er



The diagram shows the load possibilities of spur lines NAYY via the use of a line voltage regulator with a control range of 6 x 6V steps (36V/ phase) .

For the calculation it was assumed that at the end of the line, i.e. behind the line voltage regulator, an output voltage of 230 / 400V was adjusted as well. The calculation is based on cos-phi of about 0.9.

The transmissible power can be further increased by the application of line voltage regulators with pre-stages and/or 8V steps, which could result in control ranges of + 48V or also + 64V / phase.

See diagrams + 48V and +64V

Diagram NAYY + 36V



The diagram shows the load possibilities of spur lines NAYY via the use of a line voltage regulator with a control range of 6 x 8 V steps (48V/ phase) .For the calculation it was assumed that at the end of the line, i.e. behind the line voltage regulator, an output voltage of 230 / 400V was adjusted as well.

The calculation is based on cos-phi of about 0.9.

The transmissible power can be further increased by the application of line voltage regulators with pre-stages , which could result in control ranges of + 64V / phase.

See diagrams +64V

Diagram NAYY + 48V



The diagram shows the load possibilities of spur lines NAYY via the use of a line voltage regulator with a control range of 6 x 8V steps and a pre - stage of 16 V (64V/ phase) .For the calculation it was assumed that at the end of the line, i.e. behind the line regulator, an output voltage of 230 / 400V was adjusted as well.

The calculation is based on cos-phi of about 0.9.

The transmissible power can be further increased by the application of line voltage regulators with additionel pre-stages.

Diagram NAYY + 64V



Design and mode of operation

The intention is to offset the voltage loss or the excessive voltages in the low-voltage networks (tail cabling!) through the automatic regulation. For this purpose, the line-voltage regulator is developed, which is created for installation outdoors as a result of its weatherproof design.

The most common models are built for continuity currents of 50 to 200 A. The control range usually amounts to ± 36 V and/or ± 48 V in stages of 6 x 6 and/or 6 x 8 V in each phase. Greater voltage pulses up to 12 V per stage are possible. In particular cases the whole control range can be fundamentally extended again by preselector stages. Contact us about system problems, we would be happy to advise you.

Design of the regulator

Every three-phase current network regulator consists of three regulated transformer cascades independent of each other. A stored-program controller for rough climatic conditions computes the required number of the transformer stages to be actuated, and in the event of voltage fluctuations, switches these on or off as required, within a range of 300 500 ms.

All the contactors are located in a collective casing, including the three reversing starter groups, which facilitate the input voltages to be regulated upwards or downwards with the same transformers.

Each of the 6 x 6 V (8 V) stage transformers possess a primary coil of 230 V and a secondary coil of 6 or 8 V, by which the secondary coil, depending on the size of the system, is rated for 50 - 300 A (greater currents upon request).

The contactors short-circuit the 230 V coils in the switched-off state. As a result, the individual transformer has no magnetisation losses at all in the no-load running. If required, the 230 V coil is connected to the voltage, by which the 6 V and/or 8 V coil is activated and this voltage is added to the incoming mains voltage (and/or subtracted from it).

The excess voltages occasionally occurring with the activation of the transformers are shunted via switch arcs. Through damping resistors, which are housed in a separate box, the arc is lowered to an amperage harmless for the contactors.



The line- voltage regulator for the foundation installation is embedded in a double deep cable junction cabinet, suitable for the mounting on a normal base. Above left is the opened master control unit with the stored-program controller and guard casing. A measuring transducer activated before the stored-program controller converts the effective values of the 3 regulated voltages into a direct voltage suitable for the stored-program controller.Above right is the power section, comprising 6 stage transformers for each phase. Below are the NH fuse blocks for the fitting of the cable for a maximum of 95mm²...

On the left the line -voltage regulator is being prepared for dispatching. It is delivered mounted on wooden planks. This enables the line -voltage regulator to be easily transported with a fork-lift truck.

To assemble on-site the roof can be unscrewed, so that you can access the transport eyes.

The cabinet is accessible from two sides and therefore fitted with 4 doors for the integration of altogether 2 standard profile half cylinders.

Line- voltage regulator Details



Design features:

Offsetting of the voltage losses up to 25%, with the use of a preselector stage over 40%. Because of this, a multiplication of the cable load capacity is attained with adherence to the constant voltage.

The high control rate, ca. 300 500 ms, for the whole control range. The start sequence with the heavy-running motors is normalised and/or once again possible.

Symmetrical balancing of the phase voltages with the asymmetric load by the individual activation of each phase.

Throughput rating: 34, 68, 136, 200 und 300 kVA.Control rate: 300 - 500ms.

Individual activation of each phase: Because of this the asymmetries, the neutral displacements and voltage increases, determined by the uneven loads in the three phases, are balanced.

Low-loss regulation: The efficiency factor lies at 98%. In the no-load running with all quantities the losses lie below 30 VA.

Weatherproof design: The line- voltage regulators for the pole installation (sheet steel) are equipped with pole straps. The polyester design is suitable only for mounting on a foundation base.

Maintenance-free operation: We recommend an inspection of the line -voltage regulator in intervals of one or two years.

Module principle: Easy replacement possibility of all structural components.

Economic efficiency:

The line -voltage regulators have been in use for over 40 years. They have become reliable components of the system construction. It has been proven that the line- voltage regulator is not only suitable for temporary application, but also often durable as a final solution because of the high total efficiency.



line voltage regulator type NRF

line voltage regulator type NRM



Line- voltage regulator in short-circuitZeroing condition

In the event of short-circuits behind the line -voltage regulator (K) the inherent resistance of the unit exerts only a low influence on the level of the short-circuit current.

Picture: Equivalent network diagram Line- voltage regulator

Through measurements on the various line -voltage regulators and in different systems with good approximation the intrinsic impedance of the 6-stage transformer series was measured with

Z = 0,06 bis 0,08 Ohms.

The ohmic resistance lies between the values R = 0.036 and 0.040 Ohms.

The reactive impedance lies between the values X = 0.05 and 0.07 Ohms.

Picture: Transformer series (switched-off)

Measurement results:

Depending on the momentary closed-circuit condition of the line-voltage regulator, before the occurrence of the short circuit, the impedance of the loop fluctuates between 0.08 and 1.22 Ohms. After the decrease in the transformer contactors, as a result of the breakdowns of the voltage, the final resistance of approximately 0.08 Ohm is set within 10 to 20 ms.

R

L1

N

R( K )

RR

X X

X

line-voltage-regulators



Connecting the line- voltage regulatorL1

Input

L1 O

utp

ut

L2 Input

L2 O

utp

ut

L3 Input

L3 O

utp

ut

Clamps to bridge the line- voltage regulator

N N

Note: If the line- voltage regulator is put out of operation, the NH fuse blocks andmeters are to be pulled. The jumpers can then be employed, with which theline- voltage regulator is galvanically decoupled from the mains network. If the power supply is not interrupted, all the automatic circuit breakers must beswitched off. No more stage transformers may be switched on.

This only works, if no voltage difference can be measured between the input and output.Check the measurements again!!

Bag with jumper

Base

730

GFK1

GFK2



1130 630

1260

Base Base

Line voltage regulator cabinetwith 4 swivel doors

Glass fiber reinforced polyesterInternational protection: IP44

Prepared for the accomodationof 2 safety locks with asingle-profile cylinder

The base is not included in the standard (it can besupplied as an option)

* measurement for socket-fitting





1300

560

780

1100

Cabinet M1 for mast-fitting

The cabinet is planned for fitting on wooden-pole or girder-mast.

We deliver two clamps as componente parts which provide easy and fast construction on the mast. It is useful to save the clamps respectively the cabinet on the mast with corresponding screws against wringing or slipping.



Technical Data

General Data for all voltage regulators

Temperature Range: -25°C +45°CNominal voltage 3x230/400 V 50-60 HzRegulation: 3 x one phaseRegulation rate/ phase: typically 0,3 s max. 0,7 sMeasuring system: root mean square (voltage)Regulation process: tap-change operation, system WALCHERLocking system: locks with a single-profile cylinder, safety lockEngineer standards: DIN EN 60204, DIN EN 60439-1, DIN VDE 0100,EMV guidelines: DIN EN 50081-1, DIN EN 50082-1

WA-NRH-x34 (+-36V)

WA-NRH-x69 (+-36V)

WA-NRH-x92 (+-36V)

WA-NRH-xV34 (+48-24V)

WA-NRH-xV69 (+48-24V)

WA-NRH-xV92 (+48-24V)

WA-NRH-x34 (+-48V)

WA-NRH-x69 (+-48V)

WA-NRH-x92 (+-48V)

WA-NRH-xV34 (-48+24V)

WA-NRH-xV69 (-48+24V)

WA-NRH-xV92 (-48+24V)

WA-NRH-x34 (+-60V)

WA-NRH-x69 (+-60V)

WA-NRH-x92 (+-60V)

WA-NRH-xV34 (+64-32V)

WA-NRH-xV69 (+64-32V)

WA-NRH-xV92 (+64-32V)

WA-NRH-xV34 (-64+32V)

WA-NRH-xV69 (-64+32V)

WA-NRH-xV92 (-64+32V)

34kVA

69kVA

92kVA

34kVA

69kVA

92kVA

34kVA

69kVA

92kVA

34kVA

69kVA

92kVA

34kVA

69kVA

92kVA

34kVA

69kVA

92kVA

34kVA

69kVA

92kVA

5,4kVA

10,8kVA

14,4kVA

7,2kVA

14,4kVA

19,2kVA

189-277V

189-277V

189-277V

177-259V

177-259V

177-259V

230+-5V

230+-5V

230+-5V

230+-5V

230+-5V

230+-5V

ca. 20W

ca. 20W

ca. 20W

ca. 80W

ca. 140W

ca. 240W

ca. 20W

ca. 20W

ca. 20W

ca.130W

ca.180W

ca.240W

ca.130W

ca.180W

ca.240W

ca. 20W

ca. 20W

ca. 20W

ca. 80W

ca. 140W

ca.240W

580W

960W

1150W

740W

1300W

1500W

Nominalpower

Typepower

Inputvoltage

Outputvoltage

Power losses no- load

Power losses nominal load

Weightkg

Nominal load

98,3%

98,6%

98,7%

97,7%

98,2%

98,4%

250

350

410

280

410

490

7,2kVA

14,4kVA

18kVA

7,2kVA

14,4kVA

19,2kVA

9,0kVA

18kVA

24kVA

9,6kVA

19,2kVA

24kVA

9,6kVA

19,2kVA

24kVA

177-288V

177-288V

177-288V

201-283V

201-283V

201-283V

165-295V

165-295V

165-295V

161-267V

161-267V

161-267V

230+-6V

230+-6V

230+-6V

230+-5V

230+-5V

230+-5V

230+-8V

230+-8V

230+-8V

230+-6V

230+-6V

230+-6V

230+-6V

230+-6V

230+-6V

760W

1100W

1200W

740W

1300W

1500W

97,8%

98,4%

98,6%

97,7%

98,2%

98,4%

890W

1300W

1300W

1010W

1460W

1600W

1010W

1460W

1600W

97,4%

98,4%

98,6%

97,1%

97,9%

98,3%

97,1%

97,9%

98,3%

285

410

410

280

490

490

320

410

560

360

490

490

360

490

490

193-299V

193-299V

193-299V

Voltage regulator 34 kVA





WA-NRH-F150 (+-36V)

WA-NRH-F207 (+-36V)

WA-NRH-F300 (+-36V)

WA-NRH-FV150 (+48-24V)

WA-NRH-FV207 (+48-24V)

WA-NRH-FV300 (+48-24V)

WA-NRH-F150 (+-48V)

WA-NRH-F207 (+-48V)

WA-NRH-F300 (+-48V)

WA-NRH-FV150 (-48+24V)

WA-NRH-FV207 (-48+24V)

WA-NRH-FV300 (-48+24V)

WA-NRH-F150 (+-60V)

WA-NRH-F207 (+-60V)

WA-NRH-F300 (+-60V)

WA-NRH-FV150 (+64-32V)

WA-NRH-FV207 (+64-32V)

WA-NRH-FV300 (+64-32V)

WA-NRH-FV150 (-64+32V)

WA-NRH-FV207 (-64+32V)

WA-NRH-FV300 (-64+32V)

150kVA

207kVA

300kVA

150kVA

207kVA

300kVA

150kVA

207kVA

300kVA

150kVA

207kVA

300kVA

150kVA

207kVA

300kVA

150kVA

207kVA

300kVA

150kVA

207kVA

300kVA

23,4kVA

32,4kVA

47kVA

31,2kVA

43,2kVA

62,5kVA

189-277V

189-277V

189-277V

177-259V

177-259V

177-259V

230+-5V

230+-5V

230+-5V

230+-5V

230+-5V

230+-5V

ca. 40W

ca. 50W

ca. 60W

ca. 220W

ca. 300W

ca. 240W

ca. 40W

ca. 50W

ca. 60W

ca.250W

ca.300W

ca. 240W

ca.250W

ca.300W

ca. 240W

ca. 40W

ca. 50W

ca. 60W

ca. 220W

ca. 300W

ca. 240W

1600W

1900W

2500W

1700W

2500W

3300W

98,9%

99,0%

99,1%

98,8%

98,8%

98,9%

540

715

735

640

865

903

31,1kVA

43,2kVA

62,5kVA

31,2kVA

43,2kVA

62,5kVA

39,6kVA

54kVA

78,2kVA

42kVA

57,6kVA

83,3kVA

42kVA

57,6kVA

83,3kVA

177-288V

177-288V

177-288V

201-283V

201-283V

201-283V

165-295V

165-295V

165-295V

161-267V

161-267V

161-267V

230+-6V

230+-6V

230+-6V

230+-5V

230+-5V

230+-5V

230+-8V

230+-8V

230+-8V

230+-6V

230+-6V

230+-6V

230+-6V

230+-6V

230+-6V

2050W

2250W

4100W

1700W

2500W

3300W

98,6%

98,9%

98,6%

98,8%

98,8%

98,9%

2150W

2800W

5500W

2700W

3000W

5400W

2700W

3000W

5400W

98,5%

98,6%

98,2%

98,2%

98,6%

98,2%

98,2%

98,6%

98,2%

570

770

860

640

865

903

610

770

1040

750

883

1070

750

883

1070

193-299V

193-299V

193-299V




Temperature Range: -25°C +45°CNominal voltage 3x230/400 V 50-60 HzRegulation: 3 x one phaseRegulation rate/ phase: typically 0,3 s max. 0,7 sMeasuring system: root mean square (voltage)Regulation process: tap-change operation, system WALCHERLocking system: locks with a single-profile cylinder, safety lockEngineer standards: DIN EN 60204, DIN EN 60439-1, DIN VDE 0100,EMV guidelines: DIN EN 50081-1, DIN EN 50082-1

Technical Data

General Data for all voltage regulators

Nominalpower

Typepower

Inputvoltage

Outputvoltage

Power losses no- load

Power losses nominal load

Weightkg

Nominal load



Production programme

Switchgearandcontrol systems

Power planttechnology

Fast(300-700ms)voltage regulators34-200 kVAfor long lowvoltage lines

Energy manage-ment

Maximumdemandmonitors

Dataloggersfor harmonicsand netanalysis

Datalogging

Alarm messageand measurementdevices

Transformers

custom-made products

Electronics assembly workand development

We adapt ourself to the requirements of our customers. Address us !

Documents

Voltage Regulator