A New Approach To The Design Of Class E MOSFET RF Power Osciuator

Radio frequency power oscillator is a common electronic devices that can concert DC energy to high-frequency AC energy automatically. It has been the core technology for RF power supply design and widely used in many fields such as industrial, military, scientific research and so on. The role it plays in inductive coupled plasma source, RF induction heating, laser excitation is irreplaceable.Application requirements promotes the development of the technology. Great attention had been payed to the search of RF power oscillator technology both at home and abroad. High-frequency, high-power, high-efficiency represented the development direction of this technology. Traditional power oscillator in power devices usually worked in class A, B or C state, the efficiency was limited because the efficiency improvement mainly based on conduction angle reduction, and it has become more and more difficult to meet the high efficient and high power requirement in practical application. Looking for a new design method for RF power oscillator become imperative. On this occasion, Class E RF power oscillator become a new research hot spot because there is no voltage and current overlap on the drain of the transistor and the theory efficiency is as high as100%.The main purpose of this topic is to design a high efficiency RF power oscillator, which working at the frequency of13.56MHZ, providing an output power of100W, and ensuring an efficiency more than90%. Starting from the basic theory of oscillators, which mainly focused on the performance of switch mode amplifiers, the design scheme is given. Combining with the equivalent conversion of the circuit using transistor switch model and the work conditions of oscillators,the parameters of related components is proposed by solving mathematical equations. Then, simulation work has been carried out, using Agilent RF simulation software, ADS. According to the voltage and current waveform on the drain electrode, the work condition of the oscillator is analyzed and the parameters is optimized. The simulation results show that the design goal,100W output power,90%efficiency has been realized very well. Finally, printed circuit board design and debugging is finished and the experimental results prove the rationality of this design method, which lay a good foundation for subsequent work.