EPE Association: EPE 2023 - LS3c: Grid Connected Converters

EPE 2023 - LS3c: Grid Connected Converters
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 2023 ECCE Europe - Conference > EPE 2023 - Topic 02: Power Converter Topologies and Design > EPE 2023 - LS3c: Grid Connected Converters

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   A High Power Density Three-Phase Three-Level Hybrid IGBT/SiC Interleaved Active Neutral Point Clamped Voltage Source Converter
By Mohammad NAJJAR, Henning Roar NIELSEN, Lars Bech RASMUSSEN [View]
[Download]

Abstract: Increasing the power density and efficiency of power electronic converter plays an important role in the pursuit of reducing carbon footprint. This paper presents a solution to reach a higher power density and efficiency voltage source converter that can operate across a wide range of DC and AC voltages. To reach this, a modified interleaved three-level active-neutral-point-clamped (ANPC) topology is presented. A hybrid modulation technique is considered for the converter and consequently SiC switches are employed in the structure. A 350kW prototype is built and tested in both rectifier and inverter modes. In addition, the efficiency measurement is performed and the peak efficiency of 98.6\% is obtained

   Limitations and Comparisons of Small Signal Modelling Techniques in Converter Dominated Medium Voltage Networks
By Sophie COFFEY, Sam HARRISON, Agusti EGEA-ALVAREZ, Cornel BROZIO [View]
[Download]

Abstract: Grids are seeing changing SCRs, due to increased power converter penetration. This paper assesses several common small signal modelling techniques of varying computational complexity for their accuracy. Each model is tested for its accuracy limitations in response to a power disturbance for varying grid SCRs and X/R ratios and controller damping for distribution networks.

   Passivity Improvement of the Grid Connected VSI using Active Damping and Investigation of Inaccuracy of the Direct Discrete Plant Model
By Gyanendra Kumar SAH, Michael SCHÜTT, Hans-Günter ECKEL [View]
[Download]

Abstract: It is proved in this work that even the most accurate direct discrete-time plant model fails to exactly represent the PWM-based Voltage Source Inverter (VSI) connected to the grid via L-filter for all grid conditions due to the incapability to sample the present average voltage at the Point of Common Coupling (PCC). Thus, a state observer derived from the direct discrete-time plant model can not accurately estimate future signals to compensate for the unavoidable digital delays forall frequency ranges. Therefore, this compensation method does not provide passivityto the PWM-based converter. Active damping is a simple and straightforward solution to improvethe passivity of the converter by increasing the converter's positive resistance. But the activedamping in the discrete-time domain could deteriorate the passivity plot if not done correctlydue to delays in the system. An accurate way to realize the active damping is proposed to improvethe passivity of a PWM-based power converter.

EPE 2023 - LS3c: Grid Connected Converters
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 2023 ECCE Europe - Conference > EPE 2023 - Topic 02: Power Converter Topologies and Design > EPE 2023 - LS3c: Grid Connected Converters
	[return to parent folder]

	A High Power Density Three-Phase Three-Level Hybrid IGBT/SiC Interleaved Active Neutral Point Clamped Voltage Source Converter By Mohammad NAJJAR, Henning Roar NIELSEN, Lars Bech RASMUSSEN	[View] [Download]
Abstract: Increasing the power density and efficiency of power electronic converter plays an important role in the pursuit of reducing carbon footprint. This paper presents a solution to reach a higher power density and efficiency voltage source converter that can operate across a wide range of DC and AC voltages. To reach this, a modified interleaved three-level active-neutral-point-clamped (ANPC) topology is presented. A hybrid modulation technique is considered for the converter and consequently SiC switches are employed in the structure. A 350kW prototype is built and tested in both rectifier and inverter modes. In addition, the efficiency measurement is performed and the peak efficiency of 98.6\% is obtained

	Limitations and Comparisons of Small Signal Modelling Techniques in Converter Dominated Medium Voltage Networks By Sophie COFFEY, Sam HARRISON, Agusti EGEA-ALVAREZ, Cornel BROZIO	[View] [Download]
Abstract: Grids are seeing changing SCRs, due to increased power converter penetration. This paper assesses several common small signal modelling techniques of varying computational complexity for their accuracy. Each model is tested for its accuracy limitations in response to a power disturbance for varying grid SCRs and X/R ratios and controller damping for distribution networks.

	Passivity Improvement of the Grid Connected VSI using Active Damping and Investigation of Inaccuracy of the Direct Discrete Plant Model By Gyanendra Kumar SAH, Michael SCHÜTT, Hans-Günter ECKEL	[View] [Download]
Abstract: It is proved in this work that even the most accurate direct discrete-time plant model fails to exactly represent the PWM-based Voltage Source Inverter (VSI) connected to the grid via L-filter for all grid conditions due to the incapability to sample the present average voltage at the Point of Common Coupling (PCC). Thus, a state observer derived from the direct discrete-time plant model can not accurately estimate future signals to compensate for the unavoidable digital delays forall frequency ranges. Therefore, this compensation method does not provide passivityto the PWM-based converter. Active damping is a simple and straightforward solution to improvethe passivity of the converter by increasing the converter's positive resistance. But the activedamping in the discrete-time domain could deteriorate the passivity plot if not done correctlydue to delays in the system. An accurate way to realize the active damping is proposed to improvethe passivity of a PWM-based power converter.