This paper reviews the high-frequency inverters for WPT systems, summarizes the derived topologies based on power amplifiers and H-bridge inverters, investigates the main factors restricting the development of high-frequency inverters, and analyzes the research directions for future development.
What is a high frequency inverter?
I. INTRODUCTION Many applications – ranging from industrial plasma generation to wireless power transfer – require inverters (or power amplifiers) that can deliver power at high frequency (HF, 3-30 MHz).
Can inverters provide efficient delivery of high-frequency power into variable load impedances?
VI. CONCLUSION This paper introduces an inverter architecture and associated control approach for providing efficient delivery of high-frequency power into variable load impedances while maintaining resistive/inductive loading of the constituent inverters for ZVS soft switching.
Why are HF inverters so expensive?
Abstract—Efficient generation and delivery of high-frequency (HF, 3-30 MHz) power into variable load impedances is difficult, resulting in HF inverter (or power amplifier) systems that are bulky, expensive and inefficient.
In practice, one can utilize any type inverter suitable for HF operation under resistive/inductive loading; amplitude control of the individual inverters can be realized through any suitable means (e.g., supply voltage modulation, phase-shift or outphasing control, pulse-width modulation, etc.).
How do HF inverters work?
Inverter designs at HF generally utilize fundamental-frequency inductive loading of the inverter transistor(s) to achieve the zero-voltage switching transitions necessary for high efficiency.
How do you modulate an inverter output amplitude?
Modulation of the individual inverter output amplitudes (as necessary for the proposed architecture) is most easily realized by modulating the inverter supply voltages (i.e., using dc-dc converters to vary the inverter dc supplies, also known as “drain modulation”), though other means are also possible.