Search results for " Harmonic Distortion"
showing 5 items of 65 documents
On the calibration of reactive energy meters under non sinusoidal conditions
2009
This paper is focused on the problems related to the calibration of the reactive energy meters on the place of installation of the electricity meter (on-site), using the load of the same electrical system. In the presence of harmonic distortion, the behaviour of the meters can go out of the limits imposed by the theoretical calibration curve depending on the metric used by both reference standard meters and meters under test.
IEEE Std. 1459 power quantities ratio approaches for simplified harmonic emissions assessment
2018
The paper investigates the suitability of using power ratio parameters for harmonic emissions assessment at the point of common coupling (PCC). The study is carried out starting from the IEEE Std. 1459-2010 apparent power decomposition, where power factors are defined for evaluating line utilization and harmonic pollution levels. In addition, the study investigates the behavior of new parameters, which are expressed in terms of ratio between IEEE Std. 1459-2010 power quantities. The study is carried out for both single-phase and three-phase case, also considering the presence of capacitors. ? 2018 IEEE.
Current transformers effects on the measurement of harmonic active power in LV and MV networks
2011
The harmonic active power is used to determine the location of polluting loads, the direction of harmonic power flow and to estimate how consequential a certain current harmonic source is. The highest uncertainties, when measuring harmonic active power, are introduced by the current and voltage transducers. This paper presents experimental results which show the impact of current transformers (CTs) on the accuracy of the harmonic power measurements. An expression for the evaluation of the power error in distorted conditions was developed which can be easily utilized in the case of linear current transducers. It is shown how CTs cannot be considered linear transducers and how the higher the …
Investigation about selective harmonic elimination in unbalanced multilevel inverters
2022
In this paper 5 and 7 levels cascaded H-bridges inverters are considered, feeding by unequal dc voltage sources. The effect of these unbalancing operation is examined concerning harmonic analysis and total harmonic distortion of the output voltages. The system of equations, obtained by the expansion in the Fourier series of phase output voltage, is solved by applying a method of graphic solution that allows obtaining the switching angles able to eliminate the lower order harmonics.
Harmonic sources detection in power systems via nonactive power measurements according to IEEE Std. 1459-2010: theoretical approach and experimental …
2010
In this paper an enhanced decision-making strategy is presented for the detection of harmonic sources in power systems able to detect also which is the prevailing nature of the disturbance (nonlinearity or unbalance). It makes use of some simple indices, which are evaluated by means of the measurements of some nonactive power quantities, proposed by the authors and derived from the approach of the IEEE Std. 1459-2010. The decision-making rules for the proposed strategy are presented and discussed by means of simulation and experimental tests. The results obtained are presented, showing the effectiveness of the proposed strategy for the detection of the dominant harmonic source upstream or d…