Harmonic Emission Limits and Selecting PCC Location Based on the Type of Distribution System (original) (raw)
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A SOUTH AFRICAN REVIEW OF HARMONIC EMISSION LEVEL ASSESSMENT AS PER IEC61000-3-6
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A customer expects to receive a voltage supply at his installation that meets the requirements of standards like (national) grid codes, EN50160 standard etc. under normal operating conditions. On the other hand, the devices connected to a customer's installation should meet power quality (PQ) requirements as given in the IEC standards (and other relevant product standards). In contrast, present standards give very limited information about the PQ requirements at a customer's point of connection (POC). Modern household customers use many power electronic-based devices for their daily usage. Those devices inject harmonic currents and all together distort the network's voltage. It is noticed from surveys that harmonic-related inconveniences are increasing in the power system. Some field measurements (on harmonics) in the Dutch low-voltage (LV) network will be discussed in this paper. Also, harmonic simulation is done on a typical LV network that supplies electricity to several households. Both the field measurements and simulation results are compared with the limit values of the standards. Further, harmonic current emission limits at different customers' installations are derived. This information would be helpful for the customers to know their rights and responsibilities in the network. Additionally, a proposal is made about new planning level values of harmonic voltages in the network. Finally, a methodology is developed to assess harmonics-related responsibilities of each of the involved parties in the power system, and it is shown where these can be applied.
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Harmonic emission assessment in high-voltage networks with a number of renewable power plants (RPP) interconnected is challenging. A sound scientific methodology readily accessible to engineers is needed to validate the compliance to grid code requirement set by the distribution system operator. Harmonic phasors recorded coherently all over the network can cause an impractical volume of data. This study investigates the opportunity to improve existing methodologies by application of the prevailing angle in a harmonic phasor as an approach to significant reduction of data and then demonstrate the evaluation of grid compliance in a network with a number of RPP interconnected. It is shown that the unrelated dynamic nature of the different non-linear energy sources does compromise the practical application of the prevailing harmonic phase angle. It is then concluded that the dynamic nature of RPP necessitates continuous monitoring of grid code requirements on harmonic emission.
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CIRED - Open Access Proceedings Journal, 2017
Harmonic emission assessment in high voltage networks with a number of Renewable Power Plants interconnected is challenging. A sound scientific methodology readily accessible to engineers is needed to validate the compliance to grid code requirement set by the Distribution System Operator. Harmonic phasors recorded coherently all over the network can cause an impractical volume of data. This paper investigate the opportunity to improve existing methodologies by application of the prevailing angle in a harmonic phasor as an approach to significant reduction of data and then demonstrate the evaluation of grid compliance in a network with a number of Renewable Power Plants interconnected. It is shown that the unrelated dynamic nature of the different non-linear energy sources does compromise the practical application of the prevailing harmonic phase angle. It is then concluded that the dynamic nature of Renewable Energy Plants necessitates continuous monitoring of grid code requirements on harmonic emission.
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IEEE Std. 1459 power quantities ratio approaches for simplified harmonic emissions assessment
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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.
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This article investigates the feasibility of using a simplified approach, based on the measurement of power ratio parameters, for harmonic emissions assessment at the point of common coupling (PCC). The proposed approach comes from the common concept of power factor correction and the definitions of the IEEE Std. 1459-2010, where line utilization and harmonic pollution levels are evaluated by means of ratios between the power quantities of the apparent power decomposition. In addition to the IEEE Std. 1459-2010 indicators, in this article, the behavior is studied of additional parameters that are conceptually similar to those defined by the IEEE Std. 1459-2010. The suitability of such parameters is discussed, for both singleand three-phase balanced/unbalanced cases, taking into account both their behavior in different scenarios and their effectiveness when the measurement uncertainty is taken into account. The study is supported by some simulation results that have been obtained on an IEEE benchmark power system, which allows reproducing linear and nonlinear load conditions, balanced and unbalanced operating conditions, and the presence of capacitors for power factor correction.