Research On An Automatic Test System For Gas Discharge Tube

As a common surge protection device,gas discharge tubes are widely used in civil and military applications.Its performance directly affects the safety of electronic equipment and personal safety,so the research on its response performance and life assessment is very important.A gas discharge tube automatic test system prototype is designed and developed on the basis of system safety,because the gas discharge tube works under high pressure.It mainly includes two parts: the design of the hardware test system for the discharge tube and the development of the automatic test application software.The hardware test system of this paper includes the high voltage power supply,the high voltage pulse conditioning module and the signal acquisition and adjustment module to realize the automatic acquisition and adjustment of the instantaneous criterion signal of the response of the discharge tube.In order to realize the accurate measurement of the response time of the discharge tube,the high voltage power supply requires the peak peak of output ripple voltage to be less than 1%.In order to ensure the stability and reliability of the output voltage,the high voltage power supply designed in this paper is designed with a compound power supply.The front stage uses the PWM control half bridge topology as the switch stable voltage source to provide the DC transmission for the rear stage.The output voltage is linear and the output of high quality and stable voltage is achieved by using a linear regulated power supply at the later stage.The output voltage ripple can be reached 16 mV,and the output voltage is 100-2000 V linear.The input protection circuit of high voltage power supply,rectifier filter,half bridge boost main circuit,feedback loop,control loop,output rectifier filter,output DC-DC power supply,auxiliary power supply and high frequency boost transformer are given in detail,and the parameters calculation and hardware selection of important devices are carried out.The High-Voltage pulse conditioning circuit uses the hydrogen thyristor as the main control device to realize the adjustable duty ratio of the high voltage test pulse.The signal acquisition module uses high speed optocoupler isolation sampling to quickly extract the response time criterion signal.In order to achieve the safe and reliable operation of the test system in high voltage environment,the test cabin door chain protection function and emergency stop button are specially set up.The application software part selects LabVIEW 2016 as the development platform,and introduces the object-oriented software programming architecture and modular design idea.First,the design method of data acquisition system based on LabVIEW 2016 is analyzed.Secondly,the development and design of interactive system login interface,trial igniting branch event,starting ignition branch event,data acquisition branch event,file storage branch event and system running interface are developed.At last,the debugging process of the hardware and software of the prototype is given.The experimental results of the prototype and the waveform of the typical test results are analyzed.The minimum response time of the test tube can be tested by the field experiment.The minimum response time is 5 microseconds.The test results show that the developed prototype realizes the accurate measurement of the response time of the gas discharge tube while ensuring the safe operation of the equipment,and achieves the expected design goal.