Static Var Compensator (SVC), 3 Dynamic Power Factor ... the power factor in an arc furnace application or any other similar industrial application using an SVC minimizes the amount

© Festo Didactic 86370-00 75

When you have completed this exercise, you will be familiar with the reasoning behind the usage of power factor correction in industrial applications that absorb large amounts of reactive power from the ac power network. You will know the operating principles of SVCs when they are used for dynamic power factor correction (i.e., for dynamic reactive power compensation) in arc furnace applications and other industrial applications operating with large random peaks of reactive power demand. You will also know how an SVC controller designed for automatic reactive power control compensates the reactive power requirement of the industrial application to which it is connected.

The Discussion of this exercise covers the following points:

Power factor correction in industrial applications

Using SVCs for dynamic power factor correction

Automatic reactive power control

Power factor correction in industrial applications

In Exercise 2, you learned that SVCs are commonly used for voltage compensation in ac transmission lines since they allow tight, fast, and effective control of the voltage at the receiver end of the line (and along the line when used in transmission substations). SVCs achieve this by supplying the exact amount of reactive power required to maintain the voltage at the receiver end (or at any substation) of the transmission line at the desired value.

Just like ac transmission lines, various industrial applications absorb large amounts of reactive power during normal operation. Nowadays, most electrical power providers charge extra costs to industrial customers that have a low power factor (i.e., industrial applications that have a high reactive power requirement in comparison to their active power requirement). This is due to the fact that, even though reactive power does not produce any work, it still needs to flow in the wires of the ac power network and, thus, reduces the amount of active power that can be supplied by the network. Because of this, most large industrial customers, in order to lower energy costs, use certain means to minimize their reactive power demand. The more an industrial application can supply its own reactive power (through the use of capacitors, for example), the less reactive power the ac power network has to supply and, therefore, the higher the power factor of the application. This can lead to important savings in energy costs. Correcting (increasing) the power factor of an industrial application in such a way is called power factor correction.

In large industrial applications with a reactive power demand that varies little or varies slowly over time, power factor correction is achieved using banks of capacitors that can be switched in or out as required. This allows the amount of reactive power supplied by the capacitors to be increased or decreased in order

Dynamic Power Factor Correction Using an SVC

Exercise 3

EXERCISE OBJECTIVE

DISCUSSION OUTLINE

DISCUSSION

Exercise 3 – Dynamic Power Factor Correction Using an SVC Discussion

76 © Festo Didactic 86370-00

to meet the exact reactive power requirement of the application and keep the power factor as close to unity as possible.

On the other hand, the reactive power demand in certain large industrial applications varies greatly and suddenly over time. This is the case with arc furnace applications, as well as with several other industrial applications as diverse as rolling mills, traction systems (e.g., railroad networks), large resistance welders, and harbor cranes. These fluctuations in the reactive power demand of an industrial application can be significant and can greatly increase the amount of reactive power that the ac power network must supply, since they cannot be rapidly and effectively compensated using capacitor banks. This, in turn, lowers the power factor of the application and increases the energy cost (because of the extra costs charged by the electricity provider).

Another important effect of the large random peaks of reactive power demand produced in arc furnace applications and other similar industrial applications is that the voltage at the ac power input of the application fluctuates greatly with the reactive power demand. The higher the reactive power demand of the industrial application, the more important the voltage drop at the ac power input. These voltage fluctuations, in turn, cause a number of undesirable effects in the application, most notably light flicker (quick, repeated change in light intensity). In industrial applications requiring a particularly high amount of reactive power, these undesirable effects (voltage fluctuations, light flicker) are not only limited to the industrial application site, but can affect surrounding electrical power consumers in the ac power network. In most modern ac power networks, this cannot be tolerated.

Figure 46. SVCs are often installed nearby large harbor cranes for power factor correction of the crane power system.

Finally, in some industrial applications that stay in constant or near-constant operation (such as arc furnace applications) the voltage drops caused by the

Arc furnace in operation.



peaks of reactive power demand lead to a significant decrease in the average value of the voltage at the ac power input of the application and, thus, in the amount of active power that the ac power network supplies to the application. This reduces the productivity and therefore decreases revenues.

Figure 47. SVCs can be used in railroad networks for power factor correction of the railroad power system.

Using SVCs for dynamic power factor correction

The undesirable effects caused by the random peaks of reactive power demand generated in arc furnace applications and other similar industrial applications can be eliminated or minimized by the installation of an SVC at the ac power input of the application. When used in such a way, an SVC greatly reduces the reactive power demand of the industrial application as well as the fluctuations in this reactive power demand. The SVC achieves this by continually monitoring the reactive power demand of the industrial application and compensating for it by supplying the required amount of reactive power to the application, thereby maintaining the power factor of the application as close as possible to unity. This process is called dynamic power factor correction (or dynamic reactive power compensation).

Correcting the power factor in an arc furnace application or any other similar industrial application using an SVC minimizes the amount of reactive power that the ac power network must supply to the application and, consequently, minimizes the energy costs. It also ensures that the voltage at the ac power input of the application is maintained as close as possible to the nominal value of the ac power network voltage, and that no undesirable effect (voltage drops, light flicker) is experienced by surrounding electrical power consumers in the ac power network. Because of these effects, the installation costs of an SVC, although significant, can generally be recouped within a few years of the SVC installation.



Figure 48 illustrates the effects of adding an SVC to an arc furnace application on the voltage measured at the ac power input of the application.

Figure 48. Typical voltage fluctuations observed at the ac power input of an arc furnace application, with and without an SVC.

As Figure 48 shows, the voltage measured at the ac power input of the arc furnace application fluctuates greatly over time when it operates without an SVC due to the peaks in reactive power demand. When an SVC is added to the application for dynamic power factor correction, the voltage measured at the ac power input of the application still fluctuates slightly, but does not present any large variation as when the application operates without an SVC. The graph also shows that the average voltage at the ac power input of the application is higher when the application operates with an SVC than when it operates without. As a result, the active power supplied to the industrial application is also higher when the application operates with an SVC. Since arc furnace applications stay in constant or near-constant operation, such an increase in the average voltage at the ac power input of the application results in a higher amount of active power supplied to the application and, consequently, a higher productivity and higher revenues.

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n (

V)

Time (min)

With an SVC

Without an SVC

Gain due to the SVC



Figure 49. SVCs are often used for compensating the large random peaks of reactive power demand of industrial plants using electric arc furnaces.

Automatic reactive power control

When an SVC is used for dynamic power factor correction (i.e., for automatic reactive power compensation) in an industrial application operating with large random peaks of reactive power demand, the reactive power which the application exchanges with the ac power network is controlled so that it remains equal to 0 var. The SVC achieves this by monitoring the reactive component ( )

of the line currents flowing between the ac power network and the ac power input of the application to which the SVC is connected. The SVC uses the reactive component of the measured line currents to determine the number of TSCs to

be switched in, as well as the TCR firing angle that is required, in order to fully compensate the reactive power demand of the application (i.e., to zero the reactive power exchanged between the ac power network and the application). The block diagram of an SVC designed for dynamic power factor correction (i.e., automatic reactive power control) is shown in Figure 50. The industrial application is represented in the block diagram by a resistive inductive load.



Figure 50. Block diagram of an SVC designed for dynamic power factor correction (i.e., automatic reactive power control).

As the figure shows, two current sensors measure line currents and flowing between the ac power network and the industrial application, then send these currents to the SVC controller (which is set for automatic reactive power control). The SVC controller determines the reactive component of the

measured line currents. It compares the reactive component of the measured

line currents to the industry reactive current command (0 A) of the

SVC to determine the error in the reactive component of the line currents flowing between the ac power network and the industrial application. Using this error, the SVC controller switches TSCs in and out, and adjusts the TCR firing angle, so that the amount of reactive power which the SVC exchanges with the application zeroes the reactive component in the line currents flowing between the ac power network and the application. This ensures that the amount of reactive power which the industrial application exchanges with the ac power network is maintained as close as possible to 0 var. Note that a voltage sensor also

measures line voltage to properly synchronize the firing of the thyristors in the TCR, as well as to provide the phase angle ( ) information required to perform mathematical calculations in the controller. The operation of an SVC controller designed for automatic reactive power control is covered in further detail in Appendix D.

In automatic reactive power

control, the controlled pa-

rameter is the reactive cur-rent flowing between the

ac power network and the

ac power input of the indus-

trial application, and not the

reactive power which the

application exchanges with

the ac power network.

However, ensuring that

reactive current is equal

to 0 A causes the reactive

power which the application

exchanges with the

ac power network to be

equal to 0 var.

AC Transmission Line

Load

TCR TSC 1 TSC 2

SVC Controller (Automatic

Reactive Power Control)

Reactive Current Command

( )



Figure 51. SVC used for dynamic reactive power compensation at the Antamina mine complex, in Peru. The SVC significantly increases the amount of active power that can be supplied to the mine complex (photo courtesy of ABB).

Exercise 3 – Dynamic Power Factor Correction Using an SVC Procedure Outline


The Procedure is divided into the following sections:

Set up and connections

Operation without dynamic power factor correction

Operation with dynamic power factor correction

High voltages are present in this laboratory exercise. Do not make or modify any

banana jack connections with the power on unless otherwise specified.

Set up and connections

In this section, you will set up a circuit representing a three-phase ac transmission line supplying power to an industrial application operating with large random peaks of reactive power demand (such as an arc furnace) that is equipped with an SVC. You will then set up the measuring equipment required to study the operation of the SVC when it is used for dynamic reactive power compensation.

1. Refer to the Equipment Utilization Chart in Appendix A to obtain the list of equipment required to perform this exercise.

Install the required equipment in the Workstation.

2. Make sure the ac and dc power switches on the Power Supply are set to the O (off) position, then connect the Power Supply to a three-phase ac power outlet.

Connect the Power Input of the Data Acquisition and Control Interface to a 24 V ac power supply.

Connect the Low Power Input of the Power Thyristors module to the Power Input of the Data Acquisition and Control Interface. Turn the 24 V ac power supply on.

3. Connect the USB port of the Data Acquisition and Control Interface to a USB port of the host computer.

4. Turn the host computer on, then start the LVDAC-EMS software.

In the LVDAC-EMS Start-Up window, make sure the Data Acquisition and Control Interface is detected. Make sure the Computer-Based Instrumentation and SVC Control functions for the Data Acquisition and Control Interface are available. Also, select the network voltage and frequency that correspond to the voltage and frequency of your local ac power network, then click the OK button to close the LVDAC-EMS Start-Up window.

PROCEDURE OUTLINE

PROCEDURE

Exercise 3 – Dynamic Power Factor Correction Using an SVC Procedure


5. Connect the equipment as shown in Figure 52 and Figure 53. Use the reactors and thyristor switched capacitors in the SVC Reactors/Thyristor Switched Capacitors module to implement the TCR and the TSCs, respectively. Note that points A1, A2, A3, and A4 in Figure 52 are connected to the corresponding points in Figure 53.

Before connecting the TCR, make sure that switch S1 on the Power Thyristors module is set to the O (open) position, then set switch S2 to

the I (closed) position. Doing so connects thyristor in series with thyristor , thyristor in series with thyristor , and thyristor in series with thyristor . This reduces the number of leads required to implement the TCR.

When connecting TSC 1, make sure to close the open branch by short-circuiting the terminals linked by a dotted line.

This circuit represents an ac transmission line supplying power to an industrial application operating with large random peaks of reactive power demand. The industrial application is represented by the resistive and inductive loads. By adjusting the resistance of the resistive load and the reactance of the inductive load, it is thus possible to vary the active power and reactive power demand of the application. An SVC is shunt-connected between the receiver end of the ac transmission line and the industrial application (resistive and inductive load) for dynamic power factor correction (i.e., for dynamic reactive power compensation).



Local ac power network Line inductive

reactance

( )

Load resistors

, ,

( )

Load inductors

, ,

( )

Voltage

(V)

Frequency

(Hz)

120 60 60

220 50 200

240 50 200

220 60 200

Figure 52. Circuit for studying the operation of an SVC used for dynamic power factor correction (i.e., for dynamic reactive power compensation) in an industrial application operating with large random peaks of reactive power demand.

Three-Phase Transmission Line module

L1

L2

L3

N

Resistive load

A1 A2 A3

To SVC

A4

Inductive load

AC power network, transmission line, and resistive and inductive loads



Figure 53. Circuit for studying the operation of an SVC used for dynamic power factor correction (i.e., for dynamic reactive power compensation) in an industrial application operating with large random peaks of reactive power demand.

TSC 1 TSC 2

TCR

A1

A2

A3

A4

Three-Phase Transformer Bank module

Static var compensator

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1 2

6 7

11 12

15

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L1

L2

L3

L1

L2

L3



a In the circuit of Figure 52 and Figure 53, inputs E4, I3, and I4 of the Data Acquisition and Control Interface are used to measure the circuit parameters necessary for automatic reactive power control at the receiver end of the ac transmission line. Because of this, inputs E4, I3, and I4 cannot be used for parameter measurement using the LVDAC-EMS instrumentation.

6. Make sure the I/O toggle switch on the Three-Phase Transmission Line is set to the I position.

On the Three-Phase Transmission Line, set the inductive reactance selector to the value indicated in the table of Figure 52 corresponding to your local ac power network voltage and frequency.

Make the necessary switch settings on the Resistive Load and on the Inductive Load so that the resistance of the three-phase resistive load and the reactance of the three-phase inductive load are infinite.

7. Connect the Digital Outputs of the Data Acquisition and Control Interface to the Firing Control Inputs of the Power Thyristors module using the provided cable with DB9 connectors.

Connect Digital Output 1 and Digital Output 2 of the Data Acquisition and Control Interface to the TSC 1 Switching Control Input and TSC 2 Switching Control Input, respectively, on the SVC Reactors/Thyristor Switched Capacitors module using miniature banana plug leads.

Connect a common (white) terminal of the Digital Outputs on the Data Acquisition and Control Interface to the common terminal of the TSC Switching Control Inputs on the SVC Reactors/Thyristor Switched Capacitors module using a miniature banana plug lead.

8. In LVDAC-EMS, open the Metering window. In the Option menu of the Metering window, select Acquisition Settings to open the corresponding dialog box. Set the Sampling Window to 8 cycles, then click OK to close the dialog box. This enables a better accuracy when measuring the different parameters (e, g., reactive power) of the SVC and is necessary to measure the harmonic components produced by the SVC.

In the Metering window, make the required settings in order to measure the

rms values (ac) of the voltage (input E1) at the sender end of the ac transmission line, and the voltage (input E2) at the industrial application. Set two other meters to measure the three-phase active power and reactive power used by the industrial application [metering function PQS2 (E2, I2) 3~]. Set another meter to measure the amount of energy supplied to the industrial application [metering function W (E2, I2) 3~]. Also, set a meter to measure the numerical integral of the reactive power used by the application [metering function Q (E2, I2) 3~]. Finally, set two meters to measure the three-phase power factor of the industrial application [PF (E2, I2) 3~]. On one of these two meters, modify the type of measured power factor from True to Disp in order to measure the displacement power factor of the industrial application. These meter settings are explained in more detail below.



The three-phase reactive power represents the amount of reactive power that the industrial application absorbs from the ac transmission line. This value should remain as close as possible to 0 var when the SVC operates properly.

The reactive power does not represent the reactive power demand of the industrial application, which will be set to a value other than zero and made to vary randomly in this exercise, just as in real-life industrial applications, such as arc furnaces.

The energy supplied to the industrial application represents the total amount of watt-hours (i.e., the active power integral) supplied to the application,

while the numerical integral of the reactive power represents the total amount of var·hours exchanged between the ac power network and the industrial

application. In other words, the numerical integral of the reactive power

is the equivalent of the energy related to the active power .

Modifying the setting of one of the two power factor meters from True to Disp

causes this meter to measure the displacement power factor of the industrial application instead of the power factor . The displacement power factor, as opposed to the power factor, only takes into account the fundamental component of the measured parameters (all harmonic components are discarded).

Operation without dynamic power factor correction

In this section, you will study the operation of the industrial application without dynamic power factor correction (i.e., without dynamic reactive power compensation by the SVC). You will vary the resistance of the resistive load, as well as the reactance of the inductive load representing the industrial application, and let the application operate for 1 minute at each load setting. While doing so, you will record the sender voltage, the voltage at the industrial application, the active power supplied to the application, the reactive power absorbed by the application, the power factor of the application, and the displacement power factor of the application. Finally, you will record the amount of energy supplied to the industrial application (expressed in watt-hours), as well as the numerical integral of the reactive power absorbed by the industrial application (expressed in var·hours) when operating without power factor correction.

9. In LVDAC-EMS, open the Data Table window. Set the timer to make 900 records with an interval of 1 second between each record. This corresponds to a 15 minute period.

Set the Data Table to record the sender voltage , the voltage at the industrial application, the active power supplied to the application, the

reactive power absorbed by the application, the power factor of the application, and the displacement power factor of the application. Also, set the Data Table to record the time associated with each record.

10. Turn the three-phase ac power source in the Power Supply on.

In the Data Table window, start the timer to begin recording data.



11. Make the necessary switch settings on the Resistive Load and on the Inductive Load in order to obtain the combinations of resistance values (for resistors , , and ) and reactance values (for inductors , ,

and ) indicated in Table 6 (1st to 10

th values) corresponding to your local

ac power network voltage and frequency. For each resistance and reactance combination, wait for 1 minute, then proceed to the next combination.

a For optimal results, modify the switch settings simultaneously on the three legs of the Resistive Load and Inductive Load in order to avoid operation with an unbalanced load as much as possible.

Table 5. Combinations of resistance values (for resistors , , and ) and reactance

values (for inductors , , and ) to be used in the circuit of Figure 52 and Figure 53.

Local ac power network

Resistance values of , , and , and reactance values of , , and

Voltage

(V)

Frequency

(Hz) 1

st 2

nd 3

rd 4

th 5

th 6

th 7

th 8

th 9

th 10

th

120 60 600 600 600 400 400 1200 1200 1200 1200 400

1200 400 600 600 400 400 1200 400 1200 1200

220 50 2200 2200 2200 1467 1467 4400 4400 4400 4400 1467

4400 1467 2200 2200 1467 1467 4400 1467 4400 4400

240 50 2400 2400 2400 1600 1600 4800 4800 4800 4800 1600

4800 1600 2400 2400 1600 1600 4800 1600 4800 4800

220 60 2200 2200 2200 1467 1467 4400 4400 4400 4400 1467

4400 1467 2200 2200 1467 1467 4400 1467 4400 4400

12. Turn the three-phase ac power source in the Power Supply off.

13. In the Data Table window, stop the timer, then save the recorded data.

Clear all recorded data without modifying the record and timer settings.

14. In the Metering window, measure the amount of energy supplied to the industrial application, as well as the numerical integral of the reactive power used by the application when the application operates without dynamic power factor correction. Record both values below.

Energy W·h

Numerical integral var·h

When the values are recorded, reset both meters (i.e., the meter measuring the energy supplied to the industrial application and the meter measuring the numerical integral of the reactive power used by the industrial application).



Operation with dynamic power factor correction

In this section, you will study the operation of the industrial application with dynamic power factor correction (i.e., with dynamic reactive power compensation by the SVC). You will set the SVC for automatic reactive power compensation. You will then vary the resistance of the resistive load, as well as the reactance of the inductive load representing the industrial application, and let the application operate for 1 minute at each load setting. While doing so, you will record the sender voltage, the voltage at the industrial application, the active power supplied to the application, the reactive power absorbed by the application, the power factor of the application, and the displacement power factor of the application. You will plot on a graph the different parameters of the industrial application as a function of time, compare the curves obtained with dynamic power factor correction to those obtained without dynamic power factor correction, and analyze the results. Finally, you will record the amount of energy supplied to the industrial application (in watt-hours) as well as the numerical integral of the reactive power used by the industrial application (in var·hours) when operating with dynamic power factor correction. You will compare the values obtained with power factor correction to those obtained without dynamic power factor correction, and analyze the results.

15. Make the necessary switch settings on the Resistive Load and on the Inductive Load so that the resistance of the three-phase resistive load and the reactance of the three-phase inductive load are infinite.

16. In LVDAC-EMS, open the SVC Control window and make the following settings:

Make sure the Function parameter is set to Static Var Compensator.

Set the Control Mode parameter to Automatic Reactive Power Control. This control mode allows the amount of reactive power used by the application connected to the SVC to be automatically controlled and maintained as close as possible to 0 var. This ensures that the power factor of the application connected to the SVC is maintained at unity. In order to implement this control mode, the Data Acquisition and Control Interface requires inputs E4, I3, and I4 to be connected as shown in the circuit of Figure 52 and Figure 53.

Make sure the Controller Proportional Gain Kp is set to 0.5.

Make sure the Controller Integral Gain Ki is set to 6.

Start the Static Var Compensator function by clicking the Start/Stop button or by setting the Status parameter to Started.

17. Turn the three-phase ac power source in the Power Supply on.

In the Data Table window, start the timer to begin recording data.



18. Make the necessary switch settings on the Resistive Load and on the Inductive Load in order to obtain the combinations of resistance values (for resistors , , and ) and reactance values (for inductors , ,

and ) indicated in Table 6 (1st to 10

th values) corresponding to your local

ac power network voltage and frequency. For each resistance and reactance combination, wait for 1 minute, then proceed to the next combination.

a For optimal results, modify the switch settings simultaneously on the three legs of the Resistive Load and Inductive Load in order to avoid operation with an unbalanced load as much as possible.

19. Turn the three-phase ac power source in the Power Supply off.

In the SVC Control window, stop the Static Var Compensator function by clicking the Start/Stop button or by setting the Status parameter to Stopped.

20. In the Data Table window, stop the timer, then save the recorded data.

21. Using the data you recorded, plot on the same graph the reactive

power used by the industrial application, with and without dynamic power factor correction, as a function of the recording time.

Compare the curves of the reactive power used by the industrial application obtained with and without dynamic power factor correction. What do you observe? Explain briefly.

22. Using the data you recorded, plot on the same graph the power factor and the displacement power factor of the industrial application, obtained with and without dynamic power factor correction, as a function of the recording time.



Compare the curves of the power factor of the industrial application obtained with and without dynamic power factor correction. What do you observe? Explain briefly.

Compare the curve of the power factor of the industrial application to that of the displacement power factor of the application, obtained with dynamic power factor correction. What can you conclude? Explain briefly.

23. Using the data you recorded, plot on the same graph the sender voltage

and the voltage at the industrial application, obtained with and without dynamic power factor correction, as a function of the recording time.

Is the sender voltage obtained with dynamic power factor correction approximately equal to the sender voltage obtained without dynamic power factor correction, thus indicating that power factor correction has no effect on the sender voltage (i.e., on the ac power network line voltage)?

Yes No



Compare the curves of the voltage at the industrial application obtained with and without dynamic power factor correction. What do you observe? Explain briefly.

24. Using the data you recorded, plot on the same graph the active power supplied to the industrial application, obtained with and without dynamic power factor correction, as a function of the recording time.

Compare the curves of the active power supplied to the industrial application obtained with and without dynamic power factor correction. What do you observe? Explain briefly.

25. In the Metering window, measure the amount of energy supplied to the industrial application, as well as the numerical integral of the reactive power used by the application when the application operates with dynamic power factor correction. Record both values below.

Energy W·h

Numerical integral var·h

Exercise 3 – Dynamic Power Factor Correction Using an SVC Conclusion


26. Compare the amount of energy and the value of the numerical integral of the reactive power you measured in the previous step when the industrial application operates with dynamic power factor correction to those you measured in step 14 when the industrial application operates without dynamic power factor correction. What can you conclude? Explain briefly how these values affect the productivity and energy costs of the industrial application.

27. Do your observations in this exercise confirm that an SVC can be used to effectively correct the power factor (through reactive power compensation) of an industrial application generating large random peaks of reactive power demand?

Yes No

28. Close LVDAC-EMS, then turn off all the equipment. Disconnect all leads and return them to their storage location.

In this section, you familiarized yourself with the reasons behind power factor correction in industrial applications that absorb large amounts or reactive power from the ac power network. You learned the operating principles of SVCs when they are used for dynamic power factor correction (i.e., dynamic reactive power compensation) in arc furnace applications and other industrial applications generating large random peaks of reactive power demand. You also learned how an SVC controller designed for automatic reactive power control compensates the reactive power requirement of the industrial application to which it is connected.

CONCLUSION

Exercise 3 – Dynamic Power Factor Correction Using an SVC Review Questions


1. What is the primary reason for large industrial consumers to use some means to compensate for their reactive power demand? Explain briefly.

2. Why is it impossible to correct the power factor in industrial applications operating with large random peaks of reactive power demand using the same means as those used in industrial applications operating with a reactive power demand that does not vary or varies slowly over time? Explain briefly.

REVIEW QUESTIONS

Exercise 3 – Dynamic Power Factor Correction Using an SVC Review Questions


3. What is the effect of the large random peaks of reactive power demand generated in arc furnace applications and other similar industrial applications on the voltage at the ac power input of the application and the voltage at the ac power input of the power network electrical power consumers? Explain briefly.

4. Explain briefly how SVCs can be used to minimize the undesirable effects caused by the large random peaks of reactive power demand in arc furnace applications and other similar industrial applications.

5. Explain briefly why the installation costs of an SVC used for dynamic power factor correction in an arc furnace application or any similar industrial application can generally be recouped within a few years of the installation of the SVC.

Documents

Static Var Compensator (SVC), 3 Dynamic Power Factor ... the power factor in an arc furnace application or any other similar industrial application using an SVC minimizes the amount