DESIGN FEATURES AND THE TIME CHARACTERISTICS OF THE RAIL FOUR-CHANNEL SPARK GAP WITH FIELD DISTORTION

Abstract

The article discusses the design features of a four-channel rail arrester with field distortion and the results of the study of its time characteristics. The need for this work related to the development of such dischargers due to the lack of their analogues is due to the widespread use of capacitive energy storage devices as power sources for electrodynamics mass accelerators. At the present stage of development of science and technology, the use of such accelerators is the most promising for creating experimental stands for modeling in laboratory conditions the processes of high-speed interaction of aircraft structural elements with particles of different masses and different origins. According to the operating conditions of the experimental stands and a wide range of changes in both particle masses and interaction velocities, the amplitude values of currents through the low-inductive load of the mass accelerator vary from hundreds of kilo amperes to several million amperes at acceleration times from units to hundreds of microseconds. With this in mind, capacitive energy storage devices are made in a multi-module design. Each module is switched to the load by its own switch. To extend the range of operation of the drive, provide the required erosion resistance of the electrodes of the switch, the stability of the discharge formation at parallel operation of switches developed construction of a rail four-channel spark gap with the distortion field, experimental and theoretical study of the effect of the ratio of the geometric dimensions of the inter electrode gap for obtaining small values for the delay time of the discharge.
 
 As a result of the research, it is shown that the value of the delay time tzap depends on the shape and diameter of the main electrodes, the material of the electrodes, the distance between the main and the control electrode, the threshold voltage, as well as the degree of inhomogeneity of the field in the inter electrode gap.
 
 The obtained analytical expressions allow us to determine the values of threshold stresses and delay times, taking into account the statistical delay time and the time of discharge formation.
 
 It is established that the value of the delay time is significantly affected by the field inhomogeneity coefficient and the configuration of the control electrode.
 
 It is noted that when the operating voltage on the arrester exceeds the threshold voltage, the delay time of the switch lies in the nanosecond region.
 
 The value of the threshold voltage Upor, at which the process of direct transformation of the streamer into a spark discharge with high conductivity, followed by a breakdown of the inter electrode gap, is determined.