The Study On The Output Stability Of Plasma Surgical System

At present,the domestic market for radiofrequency ablation is enormous with about 50 billion,but foreign products occupy more than 95% of the market.Plasma ablation surgery system is a new technology,nowadays only the foreign company Arthro Care walks in the forefront of the world.However,the domestic technology has not yet formed.Based on this,the article is devoted to developing a stable,reliable and safe low-temperature plasma ablation surgical equipment.Taking the switching power supply technology as the core and the national medical equipment testing standards as the criterion,the research of this topic is completed from three aspects of hardware design,software design,debugging and optimization respectively.Hardware design is divided into two parts of power conversion and signal control.The core part of the power conversion applies DC-DC voltage regulator circuit,DC-AC inverter circuit,the filter circuit,and detailed introduces the principle of the topology.Furthermore,it also contains the drive circuit and the protection circuit.High-frequency transformer design is an essential part of the circuit,it starts from the composition of the transformer,designs the circuit parameters step by step.Control part makes use of C8051 microcontroller as the core,with temperature detection,alarm,display and other circuits,supplementes to coordinate the normal operation of the entire system of each module circuit.Software is the "soul" of the system,and mainly consists of signal processing and signal judgment.In order to ensure the orderly progress of the circuit,it adds the state detection circuit to ensure safe and reliable operation of the system.Additionally,it makes use of PI algorithm to achieve high-precision control output.Through continuous testing,this article raises the rectification and improvement measures in terms of hardware and software.In the face of EMC problems,a series of measures were put forward to pass the national medical equipment testing standards.In the electrical test,each part of the test waveform is fine;In simulated biological experiments,the effect of ablation surgery achieves the desired goal.After the above work,the final design of low-temperature plasma ablation surgical equipment has the following characteristics:(1)The system can provide 0-200W adjustable power to suit different surgical effects and surgical functions;(2)The device outputs a standard sine wave of 100 kHz,and doesn't have high-frequency harmonics to affect the human body,which is better than Arthro Care's square wave;(3)The entire output power accuracy can be controlled within 5%,much better than the national standard of 20%,so it's more secure and reliable;(4)It has a perfect safety detection mechanism,such as temperature detection,over-current or over-voltage detection and so on,to ensure circuit safety;(5)The design is humane,such as foot input,adjustable output,adjustable timing,alarm mode prompt;(6)The device has better ablation effect,ablation point concentrated,less damage,and no carbonization;(7)Through the Zhejiang Medical Device Testing Institute EMC test and safety test,the device has been applied to human clinical trials.