| 1. |
- Andersson, Marcus, et al.
(författare)
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Interfering signals and attenuation : potential problems with communication via the power grid
- 2006
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Ingår i: Proceedings of Nordic Distribution and Asset Management Conference.
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Konferensbidrag (refereegranskat)abstract
- This paper will give a general overview of the potential problems associated with remote-meter reading via the power grid and describe some of the technologies available. A comparison will be made between the power grid as a communication channel and other, dedicated and shared, channels. Examples will be given of practical cases in which the communication channel does not function in the intended way.
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| 2. |
- Bollen, Math, et al.
(författare)
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Limits for voltage distortion in the frequency range 2 to 9 kHz
- 2008
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Ingår i: IEEE Transactions on Power Delivery. - 0885-8977 .- 1937-4208. ; 23:3, s. 1481-1487
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Tidskriftsartikel (refereegranskat)abstract
- This paper addresses voltage distortion in the frequency range 2 to 9 kHz, above what is normally considered in harmonic studies. By extrapolating the voltage-distortion limits that exist in international standards for distortion up to 2 kHz, it is concluded that 0.5% of nominal voltage per 200-Hz band is a safe limit. This limit is next used to estimate the number of small generator units (1-10 kW) that can be connected to a low-voltage grid. It is concluded that in some cases the connection of one or just a few units already leads to a distortion level above the limit.
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| 3. |
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| 4. |
- Larsson, Anders, et al.
(författare)
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Distortion of fluorescent lamps in the frequency range 2-150 kHz
- 2006
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Konferensbidrag (refereegranskat)abstract
- This paper presents measurements of voltages and currents taken by fluorescent lamps with high-frequency ballast. The results are discussed in time domain, in frequency domain and in time-frequency domain. A number of different high-frequency components are present: recurrent transients, narrow-band time-invariant signals, and time-dependent signals. The increase in distortion with increasing number of lamps is studied as well. The distortion increases about linear with the number of lamps in the frequency range 2-9 kHz but shows only a minor increase or no increase at all in the frequency range 9-150 kHz.
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| 5. |
- Larsson, Anders, et al.
(författare)
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Emission and immunity of equipment in the frequency range 2 to 150 kHz
- 2009
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Ingår i: 2009 IEEE Bucharest PowerTech Proceedings. - Piscataway, N.J. : IEEE Communications Society. - 9781424422357 ; , s. 2325-2329
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Konferensbidrag (refereegranskat)abstract
- This paper gives an overview of emission and immunity standards in the frequency range from 2 to 150 kHz. Based on existing standardization a complete set of limits is proposed by the authors. A distinction is thereby made between narrowband emission, broadband emission and recurrent oscillations. The measuring technique is vital to the results. In this frequency range, there are two different sets of standards covering measurement equipment. Due to fact of development of time-domain based instrument we propose to only use this type of instruments for the whole frequency range.
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| 6. |
- Larsson, Anders, et al.
(författare)
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Evolution of the harmonic distortion from state-of-the-art computers : 2002 to 2008
- 2009
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Ingår i: CIRED 20th International Conference on Electricity Distribution. - Red Hook, NY : Curran Associates, Inc.. - 9781615675227 ; , s. 164-167
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Konferensbidrag (refereegranskat)abstract
- This paper shows trends in harmonic emission by large groups of modern computers over a 7-year period. The measurements were obtained at computer tournaments where almost exclusively the newest types of computers are used. The measurements clearly show that the harmonic distortion is decreasing significantly while the power consumption per computer does not change significantly.
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| 7. |
- Larsson, Anders, et al.
(författare)
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Measurement and analysis of high-frequency conducted disturbances
- 2007
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Ingår i: Conference proceedings. - Liege : AIM.
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Konferensbidrag (refereegranskat)abstract
- The frequency range above the "traditional" harmonic range up to about 2 to 3 kHz has been under investigation for a while but less attention has been paid to the frequency range slightly above. This paper presents measurements both in laboratory environment and in the field on different types of equipment and general long- term measurement on site in the low voltage network. The general aim of this paper is to increase the knowledge about voltage and current distortion in the frequency range above 2 kHz.
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| 8. |
- Larsson, Anders, et al.
(författare)
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Measurement of current taken by fluorescent lights in the frequency range 2-150 kHz
- 2006
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Ingår i: IEEE Power Engineering Society general meeting, 2006. - Piscataway, NJ : IEEE Communications Society. - 1424404932
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Konferensbidrag (refereegranskat)abstract
- This paper discusses measurements taken on fluorescent lights in the frequency range between 2 and 150 kHz. The presentation of the measurement results form an important part of the paper. The measurement results are presented in time-domain, in the frequency domain and in the time-frequency domain (by means of a "spectrogram"). The latter allows the study of sub-cycle changes in the current spectrum. The current taken by one lamp is compared with the current taken by two, three and four lamps. The relative high-frequency distortion reduced for frequencies above 15 kHz.
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| 9. |
- Larsson, Anders, et al.
(författare)
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Some consequences for the power grid of high densities of electronic equipment
- 2005
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Ingår i: First International Conference on Lifestyle, Health and Technology. - Luleå : Luleå tekniska universitet.
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Konferensbidrag (refereegranskat)abstract
- This paper will highlight some problems that can arrise when many different power supplies are densley connected to the electric mains. Measurements have been made on sites where numerous electronic devices are connected. The results of these measurements are presented and some of the consequences are discussed.
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| 10. |
- Larsson, Anders, et al.
(författare)
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Waveform distortion at computer festivals : 2002 to 2008
- 2008
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Ingår i: 2008 13th International Conference on Harmonics and Quality of Power. - Piscataway, NJ : IEEE Communications Society. - 9781424417704
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Konferensbidrag (refereegranskat)abstract
- This paper shows measurements of the harmonic emission by large groups of state-of-the-art computers measured at five different occasions from 2002 to 2008. The emission was measured during LAN-festivals where the participants use mainly the newest models of computer. This allows insight in the change in emission of computers during the last 6 years. The results from these measurements show that the distortion level generated by computers is decreasing while the power consumption does not show any significant change.
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