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Measured results of response characteristic of the TLT. (a) Measured waveform when a 100 ns pulse is injected. (b) Measured waveform when a 300 μs pulse is injected.
Source publication
A novel structure of transmission line transformer (TLT) with mutually coupled windings is described in this paper. All transmission lines except the first stage of the transformer are wound on a common ferrite core for the TLT with this structure. A referral method was introduced to analyze the TLT with this structure, and an analytic expression o...
Contexts in source publication
Context 1
... of 10 ns. The testing circuit is shown in Fig. 3. In this figure, R 1 (50 ) represents the internal resistance of the pulse generator. R 2 , whose resistance was 16.7 , together with the 50 sampling resistance of the oscilloscope, composed a 66.7 load which was matched with the TLT. The input and the observed output pulse waveforms are shown in Fig. 4. From the figure, amplitude of the input voltage pulse was 0.14 V, and amplitude of the observed pulse was 0.41 V, Considering voltage dividing function of R 2 , the observed voltage was only three quarters of the voltage amplitude on the matched load. So the output voltage of the TLT on the matched load was 0.55 V. it was found that ...
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... temporal shape as the input, and its rise time was 10 ns, which demonstrated that the developed TLT has a very good frequency response characteristic. A rectangular pulse with a pulse width of 300 μs was also injected into the transformer to test its ability to maintain "flat top" over a relatively long time scale. The output waveform is shown in Fig. 4(b). From this figure, a droop of 90%-10% can be obtained to response a pulse with width of 65.5 μs. The theoretic droop of the TLT was derived the same as, 8 which ...
Context 3
... of 10 ns. The testing circuit is shown in Fig. 3. In this figure, R 1 (50 ) represents the internal resistance of the pulse generator. R 2 , whose resistance was 16.7 , together with the 50 sampling resistance of the oscilloscope, composed a 66.7 load which was matched with the TLT. The input and the observed output pulse waveforms are shown in Fig. 4. From the figure, amplitude of the input voltage pulse was 0.14 V, and amplitude of the observed pulse was 0.41 V, Considering voltage dividing function of R 2 , the observed voltage was only three quarters of the voltage amplitude on the matched load. So the output voltage of the TLT on the matched load was 0.55 V. it was found that ...
Context 4
... temporal shape as the input, and its rise time was 10 ns, which demonstrated that the developed TLT has a very good frequency response characteristic. A rectangular pulse with a pulse width of 300 μs was also injected into the transformer to test its ability to maintain "flat top" over a relatively long time scale. The output waveform is shown in Fig. 4(b). From this figure, a droop of 90%-10% can be obtained to response a pulse with width of 65.5 μs. The theoretic droop of the TLT was derived the same as, 8 which ...
Citations
... Miniaturization of the PFL is an important direction for the development and application of pulsed power technology. Different methods have been applied to minimize the size of the PFL, including the stacked Blumlein line (Coogan et al., 1990;Davanloo et al., 1998;Liu et al., 2009), Marx technology (Zhang & Liu 2013), the transmission line transformer (Graneau 1990;Yu et al., 2014), generator based on Tesla transformer and pulse forming network (Su et al., 2009), and so on. Compared with a conventional single coaxial PFL, the charging voltage of a PFL using one of the aforementioned methods is decreased, making it possible to employ insulation material with high-energy density as the energy dielectric to minimize the size and weight of a PFL. ...
A coaxial-output rolled strip pulse-forming line (RSPFL) with a dry structure is researched for the purpose of miniaturization and all-solid state of pulse-forming lines (PFL). The coaxial-output RSPFL consists of a coaxial-output electrode (COE) and a rolled strip line (RSL). The COE is characterized by quasi-coaxial structure, making the output pulse propagate along the axial direction with a small output inductance. The RSL is rolled on the COE, whose transmission characteristics are analyzed theoretically. It shows that the RSL can be regarded as a planar strip line when the rolling radius of the strip line is larger than 60 times of the thickness of the insulation dielectric layer of RSL. CST modeling was carried out to simulate the discharging characteristic of the coaxial-output RSPFL. It shows that the coaxial-output RSPFL can deliver a discharging pulse with a rise time <6 ns when the impedance of the RSL matches that of the COE, which confirms the theoretical analysis. A prototype of the coaxial-output RSPFL was developed. A 49-kV discharging pulse on a matched load was achieved when it was charged to 100 kV. The discharging waveform has a pulse width of 32 ns, with a rise time of 6 ns, which is consistent with the simulation waveform. An energy-storage density of 1.9 J/L was realized in the coaxial-output RSPFL. By the method of multi-stage connection in series, a much higher output voltage is convenient to be obtained.
A sub-microsecond-range pulse generator based on an antiresonance network and transmission line transformer (TLT) is presented in this paper. The three-section antiresonance network (TSAN) and three-stage TLT take the roles of the pulse forming module and pulse voltage boosting module of this generator, respectively. The TSAN is applied to obtain a high quality and fixed flat top quasisquare pulse with fewer sections, and the three-stage TLT is used to obtain a higher voltage gain. Experimental results show that if the charging voltage of the TSAN is about 15.0 kV, the amplitude and pulse duration of the output voltage of the TSAN are about 7.2 kV and 400 ns, respectively, which correspond to the theoretical calculation results. Meanwhile, the amplitude of the output voltage of TLT is about 22.0 kV, so the voltage step-up ratio of the three-stage TLT is about 3.05. This generator displayed in the publication can transmit voltage pulses with low loss.
The design, construction, and operational characteristics of a low-impedance and low pulse drop transmission line transformer (TLT) are described in this paper. The multicore coaxial transmission line used for this transformer is different from traditional coaxial transmission line since its inner conductor consists of several high-voltage cables that are connected in parallel by using two metal disks placed at both ends of them. Simultaneously, the impedance of the coaxial transmission lines with ten cables designed in this paper is perfectly reduced from 60 to
. Moreover, the transmission lines can withstand a high voltage of several tens of kilovolts with 13.9 mm in diameter. The transmission lines were then used to construct TLTs. The transformers are wound inductively in separated cylinders made of polypropylene to enhance the isolation from the input to the output of the transformers. Consequently, the pulse drop is substantially reduced, minimizing pulse distortion in the transformer. A three-stage TLT, whose input and output impedances are 4.5 and
, respectively, was developed with the transmission lines. The experimental results show that the three-stage transformer based on the low-impedance and low pulse drop design transmission lines can achieve a voltage gain factor of almost 3.0.
Transmission line pulse transformers have been widely used in pulsed power technology. Traditional transmission line pulse transformers often use separate structures, which always introduces larger spurious parameters, and have lower voltage levels. In order to solve these problems, this note proposes a coaxial transmission line pulse transformer. A circular symmetric structure is used in the input and output ports of the coaxial transmission line pulse transformer, and there are no spurious parameters theoretically. Furthermore, this structure is suitable for hundreds of kilovolts high voltage applications. The structure and working principle of the coaxial transmission line pulse transformer are introduced in this note, and the circuit simulation research is conducted. The factors that affect the pulse transformation are analyzed. Furthermore, experimental studies of the square wave impulse response are conducted on an actual device. The result shows that the proposed coaxial transmission line pulse transformer can achieve the purpose of increasing the voltage amplitude while keeping the pulse waveform undistorted.
