GaN field-effect transistors(FET)have low conduction and switching losses in high-frequency(>MHz)resonant wireless power transfer systems.Nevertheless,such systems impose a unique stress on GaN FETs owing to their ...GaN field-effect transistors(FET)have low conduction and switching losses in high-frequency(>MHz)resonant wireless power transfer systems.Nevertheless,such systems impose a unique stress on GaN FETs owing to their non-ideal voltage waveforms.In this work,we report the observed non-ideal behavior in a 6.78 MHz magnetic resonant wireless transfer system that employs class-D GaN power amplifiers.The non-ideal waveform phenomenon existing at the output of the power amplifier is explained.The study analyzes the causes of this phenomenon,including the coupling coefficient k of the coil,the DC input voltage of the amplifier,and the load on the receiver.Each parameter is simulated and analyzed using LTspice.The influence of the phenomenon on the on-state resistance of the GaN device is proved in an experimental measurement,and the cause of the phenomenon is explained.The study combines a theoretical simulation and an experimental test to discuss the effect of this phenomenon on GaN power devices and proposes the corresponding solutions,which include the limitation of voltage,current,and power of the system,thermal management,and other protection measures.展开更多
Gallium nitride(GaN)field-effect transistors have low ON resistance and switching losses in high-frequency(>MHz)resonant wireless power transfer systems.Nevertheless,their performance in the system is determined by...Gallium nitride(GaN)field-effect transistors have low ON resistance and switching losses in high-frequency(>MHz)resonant wireless power transfer systems.Nevertheless,their performance in the system is determined by their characteristics and operation mode.A particular operating mode in a 6.78-MHz magnetic resonant wireless transfer system that employs class-D GaN power amplifiers in the zero-voltage switching mode is studied.Two operation modes,the forward mode and the reverse mode,are investigated.The nonideal effect under the device-level dynamic resistance and thermal effect are also analyzed.The dynamic resistance under different operation modes is demonstrated to have different generation mechanisms.Finally,the device characteristics with system operating conditions are combined,and the effects of temperature and dynamic resistance under different operating conditions are evaluated.展开更多
基金Supported by Shenzhen Innovator Special Fund(GRCK2017081715551149)。
文摘GaN field-effect transistors(FET)have low conduction and switching losses in high-frequency(>MHz)resonant wireless power transfer systems.Nevertheless,such systems impose a unique stress on GaN FETs owing to their non-ideal voltage waveforms.In this work,we report the observed non-ideal behavior in a 6.78 MHz magnetic resonant wireless transfer system that employs class-D GaN power amplifiers.The non-ideal waveform phenomenon existing at the output of the power amplifier is explained.The study analyzes the causes of this phenomenon,including the coupling coefficient k of the coil,the DC input voltage of the amplifier,and the load on the receiver.Each parameter is simulated and analyzed using LTspice.The influence of the phenomenon on the on-state resistance of the GaN device is proved in an experimental measurement,and the cause of the phenomenon is explained.The study combines a theoretical simulation and an experimental test to discuss the effect of this phenomenon on GaN power devices and proposes the corresponding solutions,which include the limitation of voltage,current,and power of the system,thermal management,and other protection measures.
基金Supported by the TSV 3D Integrate Micro/Nanosystem Lab(ZDSYS201802061805105)the Natural Science Foundation of Shenzhen(JCYJ20190808155007550)Shenzhen Science Plan(JSGG20180504170016884).
文摘Gallium nitride(GaN)field-effect transistors have low ON resistance and switching losses in high-frequency(>MHz)resonant wireless power transfer systems.Nevertheless,their performance in the system is determined by their characteristics and operation mode.A particular operating mode in a 6.78-MHz magnetic resonant wireless transfer system that employs class-D GaN power amplifiers in the zero-voltage switching mode is studied.Two operation modes,the forward mode and the reverse mode,are investigated.The nonideal effect under the device-level dynamic resistance and thermal effect are also analyzed.The dynamic resistance under different operation modes is demonstrated to have different generation mechanisms.Finally,the device characteristics with system operating conditions are combined,and the effects of temperature and dynamic resistance under different operating conditions are evaluated.
