EPE Association: EPE 2021 - Wide Band Gap Power Converters

EPE 2021 - Wide Band Gap Power Converters
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 2021 ECCE Europe - Conference > EPE 2021 - Topic 02: Power Converter Topologies and Design > EPE 2021 - Wide Band Gap Power Converters

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   Analysis of Quasi-two-Level Modulation for Neutral-Point-Clamped Three-level Converter with 10 kV SiC MOSFETs
By Xiang LIN [View]
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Abstract: To increase the blocking voltage level of switching device to improve the voltage class of power converters, series-connection of power semiconductor devices is an attractive solution. But it suffers voltage unbalance problem leading to reliability concerns. To avoid the direct series-connection, this paper presents an alternative solution for two series-connected SiC MOSFETs: quasi-two-level(Q2L) modulation based on the neutral-point-clamped (NPC) three-level (3L) converter. The proposed solution is very attractive for the recent 10 kV SiC MOSFETs due to several reasons: 1) the blocking voltage could be increased to 20 kV, suitable for most medium voltage applications; 2) with NPC 3L structure, the voltage balancing of series-connected devices is avoided; 3) with Q2L modulation, the total loss on clamping diodes is significantly reduced so the clamping diodes don't significantly increase converter volume. In this paper, the basic modulation strategy and its impact on the voltage balancing of dc bus capacitors will be discussed. With Q2L modulation, series-connected 3.3 kV SiC diodes with much smaller volume are chosen as an example as the clamping diodes to showcase the benefit of Q2L modulation. Meanwhile, the detail comparison of Q2L modulation is presented between NPC 3L converter and flying capacitor (FC) 3L converter. Single-phase pump-back test is conducted to demonstrate the Q2L modulation and its impact on clamping diode loss.

   Auxiliary Resonant Commutated Pole Inverter (ARCPI) with SiC MOSFETs for efficient Vehicle-to-Grid (V2G) charging
By Matthias LUH [View]
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Abstract: The need for energy storages is growing with an increasing share of renewable energy sources in the electricity grid. The roll-out of electric vehicles into the mass market will bring huge battery storage capacities into the grid, which have remained largely unused so far but could be used to temporarily store energy. One key enabler for this is low-cost, efficient and compact power electronics, like the Auxiliary Resonant Commutated Pole Inverter (ARCPI), which is a promising topology for bidirectional AC/DC converters in battery chargers. In this paper, we present the principle of operation and a simulation of the ARCPI. In addition, we provide first results from an ARCPI prototype using SiC MOSFETs designed for a power of up 22 kW, DC link voltages of up to 920 V and peak efficiencies beyond 99 \%.

   Comparative Analysis of High Speed Drive Inverter Designs using different Wide-Band-Gap Power Devices
By Niklas LANGMAACK [View]
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Abstract: In this paper, a 15 kW drive inverter design with increased switching frequency demand for the high-speed drive of an automotive electrical turbo-compressor unit is described. After comprehensive simulation-based evaluations eight inverter prototypes using different wide-band-gap power semiconductor devices are built and operated. With the aggregated measurement results the simulation models are refined and the inverter design is optimised in terms of efficiency, power density and its thermal characteristics. Finally, a fully functional drive inverter prototype is built.

   Demonstration of Ultra Low Loop Inductance on a High Efficient GaN Converter Using PCB Embedded Capacitors
By Jesper NIELSEN [View]
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Abstract: This paper presents design and layout considerations for a high efficient GaN converter on two-layer cost-effective PCB. The fast switching capabilities of GaN FETs requires very low power loop inductance. The proposed method of embedding the input capacitors to minimize loop inductance is analyzed and tested on a non-isolated buck converter using GaN switches. Ultra low power loop inductance (418 pH) was achieved by placing the bypass capacitors vertically through the board. The proposed converter has reached a maximum measured conversion efficiency of 98.6 percentage in both buck and boost mode.

EPE 2021 - Wide Band Gap Power Converters
You are here: EPE Documents > 01 - EPE & EPE ECCE Conference Proceedings > EPE 2021 ECCE Europe - Conference > EPE 2021 - Topic 02: Power Converter Topologies and Design > EPE 2021 - Wide Band Gap Power Converters
	[return to parent folder]

	Analysis of Quasi-two-Level Modulation for Neutral-Point-Clamped Three-level Converter with 10 kV SiC MOSFETs By Xiang LIN	[View] [Download]
Abstract: To increase the blocking voltage level of switching device to improve the voltage class of power converters, series-connection of power semiconductor devices is an attractive solution. But it suffers voltage unbalance problem leading to reliability concerns. To avoid the direct series-connection, this paper presents an alternative solution for two series-connected SiC MOSFETs: quasi-two-level(Q2L) modulation based on the neutral-point-clamped (NPC) three-level (3L) converter. The proposed solution is very attractive for the recent 10 kV SiC MOSFETs due to several reasons: 1) the blocking voltage could be increased to 20 kV, suitable for most medium voltage applications; 2) with NPC 3L structure, the voltage balancing of series-connected devices is avoided; 3) with Q2L modulation, the total loss on clamping diodes is significantly reduced so the clamping diodes don't significantly increase converter volume. In this paper, the basic modulation strategy and its impact on the voltage balancing of dc bus capacitors will be discussed. With Q2L modulation, series-connected 3.3 kV SiC diodes with much smaller volume are chosen as an example as the clamping diodes to showcase the benefit of Q2L modulation. Meanwhile, the detail comparison of Q2L modulation is presented between NPC 3L converter and flying capacitor (FC) 3L converter. Single-phase pump-back test is conducted to demonstrate the Q2L modulation and its impact on clamping diode loss.

	Auxiliary Resonant Commutated Pole Inverter (ARCPI) with SiC MOSFETs for efficient Vehicle-to-Grid (V2G) charging By Matthias LUH	[View] [Download]
Abstract: The need for energy storages is growing with an increasing share of renewable energy sources in the electricity grid. The roll-out of electric vehicles into the mass market will bring huge battery storage capacities into the grid, which have remained largely unused so far but could be used to temporarily store energy. One key enabler for this is low-cost, efficient and compact power electronics, like the Auxiliary Resonant Commutated Pole Inverter (ARCPI), which is a promising topology for bidirectional AC/DC converters in battery chargers. In this paper, we present the principle of operation and a simulation of the ARCPI. In addition, we provide first results from an ARCPI prototype using SiC MOSFETs designed for a power of up 22 kW, DC link voltages of up to 920 V and peak efficiencies beyond 99 \%.

	Comparative Analysis of High Speed Drive Inverter Designs using different Wide-Band-Gap Power Devices By Niklas LANGMAACK	[View] [Download]
Abstract: In this paper, a 15 kW drive inverter design with increased switching frequency demand for the high-speed drive of an automotive electrical turbo-compressor unit is described. After comprehensive simulation-based evaluations eight inverter prototypes using different wide-band-gap power semiconductor devices are built and operated. With the aggregated measurement results the simulation models are refined and the inverter design is optimised in terms of efficiency, power density and its thermal characteristics. Finally, a fully functional drive inverter prototype is built.

	Demonstration of Ultra Low Loop Inductance on a High Efficient GaN Converter Using PCB Embedded Capacitors By Jesper NIELSEN	[View] [Download]
Abstract: This paper presents design and layout considerations for a high efficient GaN converter on two-layer cost-effective PCB. The fast switching capabilities of GaN FETs requires very low power loop inductance. The proposed method of embedding the input capacitors to minimize loop inductance is analyzed and tested on a non-isolated buck converter using GaN switches. Ultra low power loop inductance (418 pH) was achieved by placing the bypass capacitors vertically through the board. The proposed converter has reached a maximum measured conversion efficiency of 98.6 percentage in both buck and boost mode.