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The FCG current recordings in experiments with FCG #1 and FCG #2. The double-arrows indicate the approximate time interval during which the contact point is within a specific section.
Source publication
This paper presents simulation results of high voltage systems powered by a high-explosives' driven helical flux compression generator, FCG. The FCG model was benchmarked using experiments performed with a small generator with initial inductance 23 µH and final inductance 0.2 µH. The generator design allows for a very fast inductance reduction in t...
Contexts in source publication
Context 1
... high-explosives loaded copper armature consists of a cylindrical part and a conical part machined from one single piece of copper. The conical end coincides with the last section (section 4) of the stator and has a cone angle of 8°. The results of two firings (FCG #1 and FCG #2) are shown in Fig. 3. The difference in the two firings is the seed current (5.7 kA and 11.2 kA, respectively). 240 Unlike ordinary generators having straight cylindrical armatures, this generator has a cylindrical armature with a conical shape towards the end. This, together with a well- insulated stator section (acting as inductive storage) facing the ...
Context 2
... FCG without it. The time of peak load voltage coincides with the time of the peak current time derivative for the generators operated in shorted mode. The load power is 135 % higher for the generator with armature end cone compared to that without it, see Fig. 12. The total deposited load energy is 50 % higher in the generator with end cone, see Fig. 13. Thus, the increase in load power is higher than the increase in load energy when using the end cone in this case. There is less difference in total deposited load energy between the two generators although it is 50% higher in the generator with end cone, Fig. 13. The generator with end cone enables a concentration of energy in a ...
Context 3
... The total deposited load energy is 50 % higher in the generator with end cone, see Fig. 13. Thus, the increase in load power is higher than the increase in load energy when using the end cone in this case. There is less difference in total deposited load energy between the two generators although it is 50% higher in the generator with end cone, Fig. 13. The generator with end cone enables a concentration of energy in a shorter pulse (89 µs and 158 µs FWHM, for generator with and without end cone, respectively). Note that for both generators the peak power and peak energy occurs for the same number of wires. Load energy for FCG with (circles) and without conical end (diamonds) Figure ...
Citations
... In the case of magnetic generators, PSG compresses the energy stored in the primary energy source into a strong magnetic flux associated with a significant current in the generation circuit, while ensuring the ability to discharge the magnetic field energy with high steepness in a short period of time (in order of tens of μs) [12]. Examples of sources of magnetic field pulses are current surge generators, superconducting generators or flux compression generators (FCG) [13][14][15]. Similarly, in the case of electric generators, the energy of the primary source is compressed in a strong electric field related to the maximum voltage of the system. ...
... Further deformation of the armature results in a reduction in the volume and the number of turns of the FCG winding, which is associated with a rapid reduction of the inductance LG and the resistance RG. With a constant value of the FCG winding magnetic flux, a rapid increase of the current occurs, up to values reaching hundreds of kA or even MA, and magnetic flux density reaching values in the order of tens of T [13,14]. The relative value of the current amplification at a time moment ki(t) of this type of generators can be estimated on the basis of the Formula (1), assuming a small influence of the total winding and load resistance (RG + RL) on the generation process. ...
This paper presents comprehensive analytical, numerical and experimental research of the compact and integrated high-power pulse generation and forming system based on the flux compression generator and the electro-explosive forming fuse. The paper includes the analysis of the presented solution, starting from the individual components studies, i.e., the separate flux compression generator tests in field conditions and the forming fuse laboratory test, through the formulation of the extended quasi-empirical components models aimed at enabling their optimal parameters determination at the early design stage and ending with the description of the integrated system studies in field conditions. Based on detailed research, it was possible to achieve very high parameters of the generated pulses, i.e., overvoltages of up to 340 kV with the available source power reaching 25 GW. A very high convergence of the simulation and the results of experimental research has been obtained. The parameters of the presented system have been compared with other literature solutions and the selected topology of the high power pulse generation and forming system has been distinguished against other available ones, e.g., based on Marx generators and forming lines.
The article presents numerical, circuital model of the magnetic flux compression generator. The model was used to study the influence of the selected generator parameters on the current gain ratio. The authors discussed the most important characteristics of the model used as the primary stage of the FCG design. The simulations were carried out using a specially designed model developed in Matlab Simulink.
The high-voltage pulse source is a key component in systems that generate high-power microwave (HPM) radiation. Different types of high-voltage pulse sources have different characteristics and interact differently with the radiation source. This paper presents a circuit simulation study of the interaction between a vircator load and three different high-voltage pulse sources. The voltage pulse sources considered, which have previously been studied experimentally, are a Marx generator, a high-voltage system based on a small explosively driven magnetic flux compression generator and a cable-based generator. The circuit simulation models have been validated by different experiments. The different voltage sources generate different shape, amplitude and duration of the voltage pulse. The effect of these differences on electric power deposition in, and impedance of, the vircator are discussed.
