The Design Of Stabilize High-powe Microwave Source

With the more and more wider application of microwave technology and the higher technological requirement, the stable high-power microwave power arises at the historic moment. The paper introduced a high-power microwave power which is controlled by single-chip and can operate stably with the functions of power setting, fault handling, adjustable and stable output power as well as real-time output.Microwave heating has many advantages compared with the traditional heating technologies: fast heating speed, uniform heating, high heat efficiency, etc. Due to these advantages, microwave heating technology has broad application prospects and attraction, thus to design a kind of stable, reliable microwave heating equipment with high performance is of significant scientific research value and commercial value.The microwave plasma technology has an extremely broad range of applications, such as plasma enhanced chemical vapor deposition, plasma surface treatment, and plasma etching. Microwave source as the core of the microwave plasma device, its instability of the output power directly restricts the application and development of microwave plasma technology. Therefore, researching high-power and outputting high stabilize microwave source is an important topic in the microwave plasma technology.Experimental data shows that when the instrument is working normally, if the magnetron threshold voltage is kept stable, the cathode-voltage remains approximately a constant value and thus the change of anode DC voltage can directly affect the output power of the magnetron. In consequence, the paper is mainly targeted at designing a high stability microwave power by controlling its magnetron anode. Through the sampling and processing of the anode current of the magnetron and make use of the PID control algorithm to figure out the control parameters to adjust the magnetic current effectively and finally make the output keep stable.The paper introduces the related theory of different microwave power modules and thoroughly analyses the filtering and sampling circuit and field adjustment circuit. Furtherly, a magnetron anode high voltage power with high stability is designed and the hardware and software implementation, the adjustment and debugging of various functional circuits in the power design are introduced in detail. Then the paper specifically introduces the structure, function and basic operation principle of magnetron as well as the properties, function and detailed parameters of the high power magnetron CK-611 used in this design.The design adopts ATmega32 single-chip microcomputer for software programming and the performance characteristics of ATmega32 are introduced. Besides, further description of the PI adjustment principle is elaborated in the chapter. According to the characteristics of the system, the incremental PI regulating control idea is applied in this system and the software control algorithm is completed in assembly language with several code comments. After the complement of the design work, a series of debugging work is conducted, including hardware debugging, software debugging and software and hardware co-debugging.In the paper, the design and verification work of stable high-power microwave power is carried out. New outlook and referenced scheme are proposed in order to obtain a microwave power with higher power and stability. A better solution of stable high-power microwave power will be found on the basis of previous work and the constant improvement of the system.