Search results for "Power Quality"
showing 10 items of 67 documents
A new phase locked loop strategy for power quality instruments synchronisation
2006
Power quality instrumentation requires the accurate fundamental frequency estimation and the signal synchronization, even in presence of disturbances. In the paper the authors present an innovative synchronization technique, based on a single phase software PLL. To evaluate how the synchronization technique is adversely affected by the application of stationary and transient disturbing influences, appropriate testing conditions have been developed, taking into account the requirements of the in-force standards. In the paper the proposed technique is described and PLL performances in presence of stationary and transient disturbances are presented
Power Quality Savings with Controlled Fault-Tolerant Power Converters
2011
Power quality is simply the interaction of electrical power with electrical equipments. If electrical equipments operate correctly and reliably without being damaged or stressed, a suitable level of power quality is assured. On the other hand, if the electrical equipment malfunctions, is unreliable, or is damaged during normal usage, power quality is poor and probably the economical loss could be preeminent over the technical one. In the scenario of the Distributed generation power quality issues will be more- over important because an higher dissemination of power conditioning equip- ment will be requested and this obviously will increase the sources of vulnera- bility for the electrical s…
Electrical Safety of Resonant Grounding
2019
The resonant grounding is one of the possible methods of system neutral grounding for the medium-voltage distribution. IEEE standards do define this grounding configuration, but important advantages and drawbacks of the resonant grounding might not be fully known, due to its rather uncommon application in North America. On the other hand, resonant grounding in Europe is imposed by the increased requirements for power quality, especially for medium-voltage industrial users, and imposed to electric utilities by Regulatory Authorities, with the purpose to protect the interests of users and consumers. Level of the continuity of the service, magnitude and phase of ground-fault currents, magnitud…
An experimental analysis of power quality in presence of single phase grid connected photovoltaic systems
2004
In this paper, an experimental power quality analysis in presence of single phase grid connected PV systems is performed in a PV system installed at the Department of Electric Engineering of the University of Palermo through a measurement system set up by the Authors. In particular the analysis has been carried out focusing the attention on voltage and current distortion, as the solar radiation varies. The corresponding Total Harmonic Distortions in voltage and current terms are reported and compared with the standards limits. The presence of interharmonic components is also discussed.
Alimentazione della Tunnel Boring Machine “Barbara”: qualità della tensione e mitigazione dei disturbi
2017
Studio attraverso simulazioni supportate da verifiche sperimentali dell’impatto sulla rete della operatività della Tunnel Boring Machine (TBM) utilizzata per lo scavo della nuova galleria inserita all’in- terno dell’itinerario Agrigento-Caltanissetta-A19.
A single-point approach based on IEEE 1459-2000 for the identification of prevailing harmonic sources detection in distorted three phase power systems
2009
This paper deals with a novel single-point strategy for the detection of prevailing harmonic sources downstream or upstream the metering section in three-phase power systems. It is an enhancement of a previous strategy, already developed by the authors and it is based on the comparison of three non-active power quantities which are based on the IEEE Std. 1459-2000 approach. The method does not require any spectral analysis of voltages and currents because it is based only on the separation of the fundamental components from the harmonic content of voltage and current. In the paper, the effectiveness of the strategy is investigated by means of simulation tests which were carried out on a IEE…
A self-synchronizing instrument for harmonic sources detection in power systems
2004
The deregulation of energy markets holds out new prospects for contract between customers and utilities, in which the price of energy can depend on voltage quality and load characteristics, as well as on the responsibility for disturbances caused to supply voltage in power systems. In this context, harmonic sources detection is one of the main problems, because of equipment sensibility and the proliferation of loads which absorb non-sinusoidal currents. In this paper the authors present a new instrument based on a time domain method for the detection of harmonic active powers in three-phase systems, which can be usefully applied even in the presence of unbalance or asymmetry. The amplitude …
Metrological characterization and operating principle identification of static meters for reactive energy: an experimental approach under nonsinusoid…
2009
In this paper, an experimental approach is proposed for the metrological characterization of the static meters for reactive energy and for the individuation of their operating principle in nonsinusoidal conditions. The proposed approach was developed by starting from the only available accuracy test condition in the presence of the harmonics introduced by the standards for active static meters. In this paper, the proposed approach is described, and some experimental tests are presented, which were performed on some meters of different accuracy classes and with both known and unknown operating principles.
A novel approach based on nonactive powers for the identification of disturbing loads in power systems
2007
In this paper, a new approach is proposed for the detection of harmonic sources in polluted power systems. It is a single- point strategy, based on a comparison among different "nonactive" power quantities proposed in literature that, in the same working conditions, assume different values at the same metering section. Some simulations tests were carried out on a standard IEEE test system proposed by other authors as a benchmark system for the analysis of multipoint measurement techniques for harmonic pollution monitoring. The obtained results show that the proposed single-point approach is in agreement with other strategies already proposed in the literature and can provide useful indicati…
A time domain strategy for the measurement of IEEE Standard 1459-2000 power quantities in nonsinusoidal three-phase and single-phase systems
2008
This paper describes a time domain technique for the detection of fundamental and harmonic components of voltages and currents, which is able to evaluate all the quantities required by IEEE standard 1459-2000. The technique does not require any spectral analysis to separate the fundamental positive-sequence components from harmonic, negative-sequence and zero-sequence ones. In the paper the development of the proposed technique is presented for three-phase systems, both three-wires and four-wires, as well as for single-phase systems. The implementation of the proposed technique on a PC-based instrument is also described and experimental results are presented. Finally, accuracy specification…