Most of the industrial loads are mainly controlled by power semiconductor devices. These devices make such loads more sensitive against power system disturbances. Thus, the power quality problems have gained more interest recently. This paper presents a review of some of the disturbances on the source side which may cause problems on the load side. Focus is given on problems associated with voltage dips. As voltage dips have been reported to be the most severe problems to industrial loads. Solutions towards such problems using power conditioning equipments are explored. Ideal sinusoidal voltage waveform is the prime electrical engineering (the IEC) does not yet use goal of electricity suppliers (called utilities) to the term power quality in any of its standard their customers. But it is not always possible documents. Instead of that, it uses the term because of normal system variations and some electromagnetic compatibility.
Keywords: Power Quality, Voltage Dips, Power Conditioning Equipments
[...] Equivalent circuit of a distribution feeder with SSC Thus, the instantaneous amplitude of uc(t) is controlled such as to eliminate any harmful effects of a system fault to the load voltage as long as the disturbance does not cause the circuit breaker to open CONCLUSION A literature review was carried out in order to explore some of the power quality problems and especially, voltage dips. To mitigate such problems, some power conditioning equipments have also been discussed. The reliability and power quality of industrial power systems can be significantly improved by optimal use of power electronics controllers REFERENCES IEEE standard dictionary of electrical and electronics terms, 6th edition, IEEE Std 1001996, IEEE, New York M.H.J. [...]
[...] Bollen, Understanding Power Quality Problems: Voltage Sags and Interruptions, New York, IEEE Press R.C. Dugan, M.F. McGranaghan, H.W. Beaty, Electrical Power Systems Quality, New York, McGraw-Hill European Standard EN 50160, “Voltage characteristics of electricity supplied by public distribution systems”. A. von Jouanne, B. Banerjee, “Assessment of voltage unbalance”, IEEE Transactions on Power Delivery, vol no October 2001, pp. 782-790. J. Lamoree, D. Mudler, P. Vinett, W. Jones and M. Samotyi, “Voltage Sags Analysis: Case Studies”, IEEE Transactions on Industry Applications, vol no July/August 1994, pp. [...]
[...] The outage costs associated with poor power quality are documented and serve as an argument to study the possible use of power conditioning equipments The effects of voltage dips, swells and flicker on end-users have been formulated in the literature such as 9]. Dips, depending on the severity and duration, can cause computer resets, memory loss, tripping of adjustable speed drives, loss of motor load, and this in turn leads to serious disruption of the production process. A. Causes and characterization of voltage dips The mean causes of voltage dips are short-circuit faults in transmission and distribution systems Large induction motors when starting and transformers when being energized can also cause voltage dips. [...]
[...] Voltage/current transients transient is that part of the change in a variable that appears during transmission from one steady state operating condition to another” Transients are of two types: impulsive and oscillatory Some equipment such as power electronic devices are very sensitive to voltage/current transients. They may be even destroyed because of transients. Impulsive transient impulsive transient is a very short duration (µs or ms) voltage or current that is unidirectional in polarity”. Impulsive transients are characterized by their peak, rise and decay times. [...]
[...] same quality issues and the solution of these problems but they have a strong overlap by using power electronic controllers in industrial distribution systems. Power quality related issues The prospective of the customer of electric are defined in Section 2. The focus on voltage dips power is to have an ideal voltage waveform. Thus, as the major problem for the industrial load is the customer's interest in power quality is mainly given in Section 3. Power conditioning equipments the voltage quality. [...]
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