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Superconducting pulsed-power supply (SPPS) provides an efficient method for both high-density inductive energy storage and high current pulse generation. An SPPS consisting of eight high-temperature superconducting pulsed-power transformer (HTSPPT) modules with XRAM methodology was designed and simulated in preliminary studies. It recycled the leakage flux energy and reduced the voltage across the opening switch with a capacitor in primary. However, the SPPS with XRAM methodology has two problems. The first one is that it can provide high pulse amplitude, but cannot provide enough width. The other one is that the ratio of the maximum capacitive energy over the total inductive energy is relatively large, which cuts down the overall system energy density. This paper proposes a modified topology of SPPS with capacitor reuse methodology. Multiple HTSPPT modules are divided into several groups. Each group shares the same capacitor. The procedure of the modified SPPS is presented in detail. A 270-kJ SPPS with capacitor reuse methodology is designed and simulated to illustrate the modified topology. With the load parameters of a small railgun, the peak value of the load current is 207.15 kA and the pulse half-height width is 5.56 ms, the ratio of the maximum capacitive energy over the total inductive energy is 11%. The characteristics of the modified topology are also described in detail in this paper. [ABSTRACT FROM PUBLISHER]

Slow transfer of energy through capacitive hybrid (STRETCH) meat grinder circuit, which was proposed by the Institute for Advanced Technology, added a capacitor into the traditional meat grinder circuit. Even though its energy density is slightly less than the corresponding pure inductance system, it can reduce the voltage across the opening switch and maintain the high multiplication factor of the opening current. The performance of the STRETCH meat grinder circuit depends on multiple parameters. The inductance ratio ( n=L1 / L2) and the capacitance (C) are the two vital factors, which have a crucial influence on the system performance, such as the voltage over the opening switch ( V_{\rm Sopm}) , the current multiplication factor ( m$ ), and the ratio of the maximum capacitive energy over the total inductive energy ( $\eta )$ . Thorough studies have been carried out in this paper on the relationship between the above two factors and the three performance criteria. This paper also discusses and analyzes the chosen of the key parameters ( $n$ and $C$ ) for a single-stage STRETCH meat grinder with 2-mH total inductance, which is made up of two serial coils with 0.95 coupling factor. The opening current of the main switch is 1 kA, which constitutes a 1-kJ inductive pulsed-power supply. It fully takes the advantage of the STRETCH meat grinder topology, intensifies the study of the inductive pulsed-power supply with higher energies, and is easy to be utilized for practical application. [ABSTRACT FROM PUBLISHER]

The superconducting inductive pulsed-power supply (SPPS) circuit consists of a high-temperature superconducting pulsed-power transformer (HTSPPT) and an auxiliary capacitor. The electrical losses and the power of the primary source can be cut down with the superconducting inductive energy storage. Although its energy density is slightly less than a purely superconducting inductive system, it can reduce the maximum voltage of the opening switch by the capacitor and achieve a high degree of current amplification factor. However, during the discharge process, the magnetic leakage flux energy stored in the primary of the HTSPPT requires the capacitor to have a certain capacity. The higher the ratio of the capacitive stored energy over the total inductive stored energy, the more the dominant position of inductive energy storage reduces. The current amplification factor ( \gamma ), the maximum voltage of the opening switch ( V_{S\max } ), and the ratio of capacitive stored energy ( \eta ) are the three main properties of the SPPS circuit, which depends on several intertwined critical parameters, such as the inductance ratio n = L2 /( L2+LL ) and the capacitance ( $C_{{\mathbf {1}}}$ ). This paper studies the influence of the critical parameters on the main circuit performance with a 1-kJ SPPS system. The detailed selection method of the critical parameters for the specific system is also discussed with a coupling coefficient of 0.95. Such a system is easy to be utilized for the basic experimental study of a small railgun. [ABSTRACT FROM PUBLISHER]

For electromagnetic emission applications that need a very high amplitude and an appropriate pulsewidth, a pulsed power supply based on multiple high-temperature superconducting pulsed power transformer (HTSPPT) modules is verified in this paper. First, the working processes of multiple HTSPPT modules are analyzed and two small experimental HTSPPTs are described in detail. Then, simulation is carried out to show the major pulse characteristics of two different discharge methods. To verify the feasibility of two discharge methods, high-current testing is carried out with the two HTSPPTs. The results show that a higher amplitude of current pulse can be achieved using synchronous parallel discharge and a larger pulsewidth of current pulse can be achieved using asynchronous parallel discharge. [ABSTRACT FROM AUTHOR]

This paper describes a compact high storage density inductive–capacitive storage module. The module is based on high-power opening switches using inverse current commutation with semiconductor devices commutation principle and a high storage density Brooks inductor. These opening switches, being able to switch-OFF pulse currents up to 14.5 kA by the counter-current subcircuit, make use of the general property of a standard high-power thyristors impedance transition from closing state to blocking state. The experimental results show that with the primary capacitor and counter-current commutation subcircuit charged voltage 3 and 2.5 kV, respectively, the charged current of the Brooks-type inductor is about 14.5 kA, with a charged time of about 4.5 ms. The output peak current of the inductive storage module is about 21 kA. The total stored energy is about 54.9 kJ while the energy density of the inductor is approximately 6.69 MJ/ \textm^3 , which is not including the primary storage and commutation unit. [ABSTRACT FROM PUBLISHER]

A new design of powerful high-voltage high-current impulse source for nanosecond megavolt charging of short forming lines (SFLs) is proposed. The first stage of the device is based on inductive energy storage. It accumulates energy supplied by the current of magnetic flux compression generator (MCG), whereas the electro-explosive opening switch is used for the energy output into intermediate SFL. In the second stage, we use a Tesla transformer with oil insulation. The results of the earlier experimental study of submegavolt charging of intermediate forming line as well as the results of calculations of the two-stage facility given in this paper demonstrate the feasibility of the device based on MCGs for nanosecond charging of SFL up to about 3 MV. [ABSTRACT FROM PUBLISHER]