Wyniki wyszukiwania - BazTech

1

Zastosowanie metody SHE do kształtowania składowych harmonicznych prądu zasilania i momentu w układzie napędowym z trójpoziomowym falownikiem NPC

Chudzik Piotr, Steczek Marcin, Tatar Karol

Przegląd Elektrotechniczny

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2023

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R. 99, nr 5

220--224

PL

W artykule przedstawiono wyniki badań symulacyjnych oraz laboratoryjnych zastosowania metody SHE w celu kształtowania widma prądu obwodu pośredniczącego i momentu w układzie napędowym z trójpoziomowym falownikiem NPC. W rozdziale teoretycznym przedstawiono zarys zjawiska powstawania harmonicznych prądu obwodu pośredniczącego i momentu w układach napędowych zasilanych z falowników. Rozdziały opisujące badania symulacyjne i laboratoryjne prezentują wyniki świadczące o użyteczności metody SHE.

EN

The article presents the simulation and laboratory test results for applying the SHE method to shape the current spectrum of the DC-link circuit and torque in a drive system with a three-level NPC inverter. The theoretical chapter outlines the phenomenon of the formation of DC-link circuit current and torque harmonics in drive systems powered by inverters. The chapters describing the simulation and laboratory tests present the results proving the usefulness of the SHE method in the discussed problem.

2

CHB inverter with DC-link capacitor balancing and total harmonic minimization

Armi F., Manai L., Besbes M.

Archives of Electrical Engineering

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2018

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Vol. 67, nr 1

81--93

EN

A cascaded H-bridge (CHB) multilevel inverter generally requires several DC sources. An alternative option is to replace the separate DC source feeding an H-bridge cell with a capacitor, while maintaining the other H-bridge cell with a real DC voltage source. In this paper a 7-level cascaded H-bridge inverter with a single DC-source is presented. This paper focuses mainly to achieve effective capacitor voltage balancing and selective harmonic elimination (SHE) based on the Newton Raphson algorithm (N–R). It shows hope to reduce the voltage ripple of the capacitors, which leads to higher power conversion efficiency with equal power distribution, reduces the initial cost, and complexity hence it is apt for industrial applications. Simulation results support the proposed control technique.

3

A study on applicability of a selective harmonic reduction method for a full operating range of a traction inverter

Szeląg M., Szeląg A.

TTS Technika Transportu Szynowego

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2015

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R. 22, nr 10

147--153, CD

EN

The article presents the problem of application of a traction inverter control strategy consisting in selective elimination of harmonics (Selective Harmonic Elimination – SHE) for shaping the spectrum of traction current. The objective of this method is to reduce the conducted disturbances generated by a traction vehicle to the level below admissible values. The selection of the order of harmonics being eliminated from a voltage spectrum influences the values of the remaining voltage harmonics, hence the harmonics spectrum of current consumed from a DC network. The presented study aimed at developing the SHE method to the extent enabling its implementation to the real drive system. The article describes the results compared with limits existing in PKP (Polskie Koleje Państwowe – eng. Polish State Railways), however the presented methodology can be successfully employed for any applicable limits in DC electric traction systems.

4

WTHD minimisation in hybrid multilevel inverter using biogeographical based optimisation

Kavitha R., Thottungal R.

Archives of Electrical Engineering

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2014

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Vol. 63, nr 2

187--196

EN

Harmonic minimisation in hybrid cascaded multilevel inverter involves complex nonlinear transcendental equation with multiple solutions. Hybrid cascaded multilevel can be implemented using reduced switch count when compared to traditional cascaded multilevel inverter topology. In this paper Biogeographical Based Optimisation (BBO) technique is applied to Hybrid multilevel inverter to determine the optimum switching angles with weighted total harmonic distortion (WTHD) as the objective function. Optimisation based on WTHD combines the advantage of both OMTHD (Optimal Minimisation of Total Harmonic Distortion) and SHE (Selective Harmonic Elimination) PWM. WTHD optimisation has the benefit of eliminating the specific lower order harmonics as in SHEPWM and minimisation of THD as in OMTHD. The simulation and experimental results for a 7 level multilevel inverter were presented. The results indicate that WTHD optimization provides both elimination of lower order harmonics and minimisation of Total Harmonic Distortion when compared to conventional OMTHD and SHE PWM. Experimental prototype of a seven level hybrid cascaded multilevel inverter is implemented to verify the simulation results.

5

Wprowadzenie do praktyki Protokołu z Kioto w latach 2005-2007

Środa B.

Materiały Ceramiczne

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2005

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R. 57, nr 1

42-44

PL

Z dniem 1 stycznia 2005 r. rozpoczął funkcjonowanie europejski System Handlu Emisjami (SHE). System ten stanowi dla 25 państw członkowskich Unii Europejskiej narzędzie do realizacji zobowiązań zawartych w Protokole z Kioto. W ramach Protokołu z Kioto Polska zobowiązała się do redukcji emisji gazów cieplarnianych w latach 2008-2012 o 6% w stosunku do poziomu z roku 1988, tj. w przypadku CO2 do limitu 448 mln ton rocznie. Obecnie, Polska dysponuje rezerwą około 130 mln ton CO2 w stosunku do zobowiązań podjętych w 1997 roku w Kioto, gdyż od roku 1988 zredukowała emisję CO2 o ponad 30%. Jak będzie funkcjonował ten system w przypadku przedsiębiorstw, uczestniczących w SHE? Czy system będzie kontynuowany po roku 2012?

EN

The European Emission Trading Scheme (ETS) began on 1 January 2005. This Scheme is adopted as a tool for implementation of the Kyoto Protocol targets set for 25 EU Member States. Poland as one of signatories is obliged to meet an 6 percent reduction target in greenhouse gas emissions (in case of CO2 the limit is 448 mln tons per year) from 1988 levels between 2008-2012. Poland has now a substantial reserve of about 130 mln tons of CO2 of the cap set in the Kyoto Protocol - the CO2 emissions decreased by over 30% compared with the emissions in 1988. How this System will work in case of Polish enterprises covered by the EU ETS? What happens after Kyoto expires?