**12. References**


According to the above results obtained from this study, THD at point 2 (29 %) of building 14 does not guarantee with IEEE 519 standers (< 20%) this well cause to reduce the life time

[1] J. Arrillaga, D. A. Bradley, and P. S. Bodger, "Power System Harmonics", John Wiley &

[2] "Recommended Practices and Requirements for Harmonic Control in Electric Power

[3] G. T. Heydt, Electric Power Quality, Stars in Circle Publications, West LaFayette, IN,

[4] R. C. Dugan, "Simulation of Arc Furnace power systems", IEEE Trans. on Industry

[5] M. F. McGranaghan, R. C. Dugan, and H. W. Beaty. "Electrical Power Systems Quality",

[6] Task force on Harmonics Modeling and Simulation, "The modeling and simulation of

[7] Victor A. Ramos JR, "Treating Harmonics In Electrical Distribution system" Technical Consultant Computer Power &Consulting Corporation, January 25, 1999. [8] M. H. Shwehdi, et Al," Power Factor Essential and causations," IEEE-PES summer

[9] Klaus Timm, Hamburg, basic Principals of electric furnaces, Edited by E. Plockinger and

[10] Hirofumi Akagi, "New Trends in Active Filters for Power Conditioning", IEEE Trans. on

[11] Antonio Silva, "Steel Plant Performance, Power Supply System Design and Power

[12] Joseph S. Subjak, Jr. and John S. Mcquilkin, "Harmonics-Causes, Effects, Measurements

[13] W.R.A, Ryckaert, J.A.L Ghijselen, J.J.M Desmet, J.A.A. Melkebeek, J. Driesen"The

[14] H. Akagi, "New trends in active filters for power conditioning," IEEE Trans. Ind. Appl.,

[15] A. Esfandiari, M. Parniani, and H. Mokhtari, "A new control strategy of shunt active

[16] IEEE recommended practices and requirements for harmonic control of electrical

and Analysis- Update" IEEE Transactions on industry applications, vol. 3, 1989, pp

influence on Harmonic Propagation of a resistive shunt harmonic impedance location along a distribution feeder and the influence of distributed capacitors",

filters for power quality improvement of highly and randomly varying loads," in

O. Etterich, John Wiley and Sons, Ltd, 1985, pp 127- 160.

Quality Aspects", 54th Electric Furnace Conference - Dec. 96.

Industry Application, Nov/Dec 1996, pp. 1312-1322.

propagation of harmonics in electric power networks Part I: Concepts, models and simulation techniques," IEEE Transactions on power Delivery, Vol. 11, NO.1,

Systems", IEEE Standard 519-1992, IEEE, New York, 1993.

Application, Nov/Dec 1980, pp. 813-818.

New York: McGraw-Hill, 1996.

Meeting Singapore, July, 2000

ICHPQ2004 Lake Placid, NewYork.

Vol. 32, No. 6, pp. 1312~1322, Nov./Dec. 1996.

Proc. ISIE2004, pp. 1297~1302, France, 2004.

power systems, IEEE Std. 519-1992, 1993

January 1996, pp.

of the transformers and cables in building 14 .

Sons, New York, 1985.

**12. References** 

1991.

55-66.


**10** 

Angela Iagăr

*Romania* 

*Politechnica University Timişoara* 

**Power Quality Problems Generated by** 

**Line Frequency Coreless Induction Furnaces** 

The increased problems in power networks impose to identify the sources of power quality deterioration. The most important parameters which affect power quality are harmonics, voltage instability and reactive power burden (Arrillaga et al., 2000). They cause low system efficiency, poor power factor, cause disturbance to other consumers and interference in the

In induction melting is noticed mainly the efficiency, high heating rate and the reduced oxidation level of the processed material, the improved work conditions and the possibility

Induction heating equipments do not introduce dust and noise emissions in operation, but

Induction-melt furnaces supplies by medium frequency converters generate fixed and variable frequency harmonics. Both current and voltage-fed inverters generate harmonics

Harmonics flowing in the network causing additional losses and decreasing the equipments lifetime. Also, the harmonics can interfere with control, communication or protection

In addition to the harmonics that are normally expected from different pulse rectifiers, large furnaces operating at a few hundred hertz can generate interharmonics (EPRI, 1999). Interharmonics can overload power system capacitors, introduce noise into transformers,

High-frequency systems, which operate at greater than 3 kHz are relatively small and limited to special applications. Electromagnetic pollution produced by the operation of these

The induction furnaces supplied at line frequency (50 Hz) are of high capacity and represent

Being single-phase loads, these furnaces introduce unbalances that lead to the increasing of power and active energy losses in the network. In case of channel furnaces it was found the presence of harmonics in the current absorbed from the power supply network. These harmonics can be determined by the non-sinusoidal supply voltages or the load's

This chapter presents a study about power quality problems introduced by the operation of line frequency coreless induction furnaces. The specialty literature does not offer detailed

nearly communication networks (Lattarulo, 2007; De la Rosa, 2006; Muzi, 2008).

of an accurate control of the technological processes (Rudnev et al., 2002).

back into power lines in the process of rectifying AC to DC (EPRI, 1999).

equipments (Arrillaga et al., 2000; George & Agarwal, 2008).

cause power quality problems in the electric power system (Nuns et al., 1993).

cause lights to flicker, instigate UPS alarms, and trip adjustable-speed drives.

nonlinearity, owed to the saturation of the magnetic circuit (Nuns et al., 1993).

information regarding the harmonic distortion in the case of these furnaces.

**1. Introduction** 

equipments is small.

great power consumers.

