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1

Comparative study of SPWM and SVPWM techniques for the control of three-phase grid connected inverter

Jarjes Muhammed K., Hussein Taha A.

Przegląd Elektrotechniczny

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2023

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R. 99, nr 5

114--119

EN

The importance of three-phase grid connected inverters has increased due to the increasing use of renewable energy such as photovoltaic energy, wind energy, and others. This study presents a comparison between two methods of controlling the work of the inverter. The first method is SPWM technique, and the second method is SVPWM. The comparison is in terms of THD level in the output voltage and current, as well as comparing the controlling steps for both methods under the same working conditions. The value of the coils and capacitors required in the filter circuit connecting the inverter and the grid are calculated for a power of 200KVA. An active power is injected from the inverter to the network, and it was found that the angle between the grid voltage and the inverter current is zero degrees, as well as reactive power is injected, and it is found that the angle became 90 degrees as expected. The MATLAB program is used to build both techniques. The study provides an analysis of voltages and currents at different locations between the inverter and the grid, in addition to the frequency analysis of these variables.

PL

Znaczenie inwerterów podłączonych do sieci trójfazowej wzrosło ze względu na rosnące wykorzystanie energii odnawialnej, takiej jak energia fotowoltaiczna, energia wiatrowa i inne. W pracy przedstawiono porównanie dwóch metod sterowania pracą falownika. Pierwsza metoda to technika SPWM, a druga metoda to SVPWM. Porównanie dotyczy poziomu THD w napięciu wyjściowym i prądzie, a także porównanie kroków kontrolnych dla obu metod w tych samych warunkach pracy. Wartość cewek i kondensatorów wymaganych w obwodzie filtra łączącego falownik z siecią obliczono dla mocy 200KVA. Moc czynna jest wprowadzana z falownika do sieci i stwierdzono, że kąt między napięciem sieci a prądem falownika wynosi zero stopni, podobnie jak moc bierna jest wtryskiwana i stwierdzono, że kąt wynosi 90 stopni, ponieważ oczekiwany. Program MATLAB jest używany do budowy obu technik. Opracowanie zawiera analizę napięć i prądów w różnych miejscach między falownikiem a siecią, oprócz analizy częstotliwościowej tych zmiennych.

2

A single-phase photovoltaic Microinverter topology based on boost converter

Ternifi Touhami, Bachir Ghalem, Aillerie Michel

Przegląd Elektrotechniczny

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2019

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R. 95, nr 4

215--217

EN

This paper presents a novel grid-connected photovoltaic Microinverter topology and its control implementation. A very significant contribution is to propose an innovative conversion structure with the aim of achieving high efficiency, easy control, high reliability and low design cost. In a first part of this contribution, we describe the proposed configuration topology. In a second part, we present the simulation tests developed in order to verify the validity and performance of its operating principle. The last part is reserved for discussion of the simulation results.

PL

W artykule opisano topologię mikroprzekształtnika współpracującego z ogniwem fotowoltaicznym. Zaproponowano nową koncepcję konwersji dla osiągnięcia prostego sterowania I małego kosztu. W pierwszej części opisano układ, w drugiej części przedstawiono wyniki symulacji a w trzeciej dyskusję wyników.

3

Deliberations about three-phase PLL technologies applied to a grid control of the renewable power system

Liu L., Liu C.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2015

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Vol. 63, nr 1

261--267

EN

An efficient phase locked loop (PLL) method is very important to improve the grid-connected efficiency and the locked speed of frequency, phase, and voltage. However, most of literatures only introduce one PLL or one modified PLL method. There are many grid faults due to the grid connection to the renewable power generating system. A comparison and analysis is very important to select the most effective PLL technology for the grid-connected control of the renewable power system. Three PLL technologies are compared at different grid faults, such as single phase voltage drop, two phase voltage drop, frequency deviation, and voltage distortion. Simulation results indicated that different PLL methods have different locked performances at different grid faults.

4

Passive filter design for three-phase inverter interfacing in distributed generation

Ahmed K. H., Finney S. J., Williams B. W.

Electrical Power Quality and Utilisation. Journal

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2007

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Vol. 13, nr 2

49-58

EN

With the growing use of inverters in distributed generation, the problem of injected harmonics becomes critical. These harmonics require the connection of low pass filters between the inverter and the network. This paper presents a design method for the output LC filter in grid coupled applications in distributed generation systems. The design is according to the harmonics standards that determine the level of current harmonics injected into the grid network. Analytical expressions for the maximum inductor ripple current are derived. The filter capacitor design depends on the allowable level of switching components injected into the grid. Different passive filter damping techniques to suppress resonance affects are investigated and evaluated. Simulated results are included to verify the derived expressions.

5

1 kW grid-connected PV system after two years of monitoring

Pietruszko S. M., Gradzki M.

Opto-Electronics Review

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2004

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Vol. 12, No. 1

91--93

EN

The paper describes performance of the grid-connected 1-kW PV system installed on a grammar school in Warsaw after two years of operation. The system consists of twenty Millennia MST-50 MV modules and inverter Sunny Boy GCI 1200. The performance of the system is continuously monitored according to guidelines in IEC 61724. Energy production in the first year was about 740 kWh and it was slightly higher than expected with respect to the simulation done before installation. In the second year, the energy production was about 680 kWh. The measured efficiency of the PV modules is about 5%, efficiency of the inverter is about 92% and efficiency of the entire PV system exceeds 4%. The performance ratio is in the range from 0.5 to 0.8.