Discharge And Model Research Of Low Temperature Plasma Ablation Knife

In modern medicine,minimally invasive surgery has become the goal of today's medical field.After decades of development,the traditional cutting method has gradually shown a series of shortcomings,such as: the operation process is cumbersome and time-consuming,requires a variety of operations,The wound has a wide range of dissection,unclear operative field,high probability of concomitant inflammation after soft tissue injury,postoperative pain and so on.The low-temperature plasma ablation knife studied in this project uses physiological saline as the working medium.During the cutting process,the surgical field is clear,and no auxiliary tools such as air compressor and gas cylinder are needed,and two surgical methods of cutting and hemostasis are provided.The use of the remaining surgical instruments is reduced,postoperative inflammation and pain are reduced,so the study of this low-temperature plasma ablation knife is very promising.In this paper,the author studied the characteristics of low-temperature plasma discharge in liquid media,and designed a new type of low-temperature plasma ablation scalpel system,including the overall design of the cutter body,the RF power supply analog circuit design,and the performance stability test dvice design.The discharge electrode in the body structure is related to the formation and stability of liquid-phase plasma,and is one of the important factors affecting the performance of lowtemperature plasma ablation knife.In addition,the overall structure of the cutter body is very compact,so designing a suitable electrode shape and structure and selecting a suitable electrode material is a major focus of this article.The power supply is designed as a high frequency pulse square wave power supply.The power analog circuit is mainly divided into four small circuit modules,which are: a rectifier filter circuit module,a protection circuit module,an inverter circuit module,and an amplifier circuit module.It focuses on the principle of each circuit module and how to suppress noise interference.The main control chip uses a mid-scale integrated device that combines analog and digital functions,the 555 timer chip,to form a multivibrator to output a square wave control signal.Multi-selector switches are used to achieve the selection of different voltage ranges,and high-voltage square-wave signal outputs are achieved using the high voltage and response time characteristics of IGBTs.Finally using pspice to complete the time domain analysis of the power circuit,pspice simulation results are ideal,in line with design standards.Also provided herein for the first time while a cryogenic scalpel plasma discharge detection device and the stability of detection method for testing the knife ablation discharge performance.According to the proportional relationship between the plasma discharge intensity and the luminous intensity,the main test device adopts a photon counter.During the plasma discharge,real-time photon acquisition is performed and the data is recorded.The discharge stability of the ablation knife is determined based on the change in the number of photons per unit time.