Design and Realization of a Bidirectional Full Bridge Converter with Improved Modulation Strategies

In this paper a Full-Bridge Converter (FBC) for bidirectional power transfer is presented. The proposed FBC is an isolated DC-DC bidirectional converter, connected to a double voltage source—a voltage bus on one side and a Stack of Super-Capacitors (SOSC) on the other side. The control law aims at the regulation either of the bus current (when the load requires power) or of the SOSC current (when the stack requires a recharge). Analysis and design of the proposed FBC are discussed. A Phase Shift Modulation (PSM) scheme is proposed, along with an improved modulation variant for the efficiency optimization, through a proper reduction of the transformer power losses. The realized prototype, compliant with automotive applications, is presented and experimental results are highlighted. The target power level is 2 kW.

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KANTHAL 70

Alloy Digest ◽

10.31399/asm.ad.ni0270 ◽

1981 ◽

Vol 30 (9) ◽

Keyword(s):

Operating Temperature ◽

Heat Treating ◽

Positive Temperature Coefficient ◽

Pure Nickel ◽

Voltage Source ◽

Voltage Regulator ◽

Positive Temperature ◽

Automotive Applications ◽

Resistance Thermometers ◽

In Series

Abstract KANTHAL 70 alloy was designed to provide a high positive temperature coefficient to electrical resistance comparable with that of pure nickel; however, it has much higher electrical resistivity than pure nickel. This makes it useful as a voltage regulator when placed in series with another electrical device across a fluctuating voltage source. Kanthal 70 has a maximum recommended operating temperature of 600 C and is used widely in resistance thermometers and in various appliance and automotive applications. This datasheet provides information on composition, physical properties, and tensile properties. It also includes information on corrosion resistance as well as forming, heat treating, and joining. Filing Code: Ni-270. Producer or source: The Kanthal Corporation.

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A GaN-HEMT Compact Model Including Dynamic RDSon Effect for Power Electronics Converters

Energies ◽

10.3390/en14082092 ◽

2021 ◽

Vol 14 (8) ◽

pp. 2092

Author(s):

Ke Li ◽

Paul Leonard Evans ◽

Christopher Mark Johnson ◽

Arnaud Videt ◽

Nadir Idir

Keyword(s):

Power Electronics ◽

Physical Model ◽

Order Reduction ◽

Power Converter ◽

Compact Model ◽

Voltage Source ◽

Power Losses ◽

Gan Hemt ◽

Operation Conditions ◽

Power Electronics Converters

In order to model GaN-HEMT switching transients and determine power losses, a compact model including dynamic RDSon effect is proposed herein. The model includes mathematical equations to represent device static and capacitance-voltage characteristics, and a behavioural voltage source, which includes multiple RC units to represent different time constants for trapping and detrapping effect from 100 ns to 100 s range. All the required parameters in the model can be obtained by fitting method using a datasheet or experimental characterisation results. The model is then implemented into our developed virtual prototyping software, where the device compact model is co-simulated with a parasitic inductance physical model to obtain the switching waveform. As model order reduction is applied in our software to resolve physical model, the device switching current and voltage waveform can be obtained in the range of minutes. By comparison with experimental measurements, the model is validated to accurately represent device switching transients as well as their spectrum in frequency domain until 100 MHz. In terms of dynamic RDSon value, the mismatch between the model and experimental results is within 10% under different power converter operation conditions in terms of switching frequencies and duty cycles, so designers can use this model to accurately obtain GaN-HEMT power losses due to trapping and detrapping effects for power electronics converters.

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