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An equivalent circuit is proposed and the viability of a resonant amplifier of the average active electric power of periodic current pulses generated in the load is theoretically substantiated. The amplifier consists of two series active-reactive circuits with a common capacitive energy storage. In the primary circuit, in the voltage resonance mode, it is charged, and the charging voltage exceeds the source voltage by a factor equal to the quality factor of the circuit. At the end of the charge to a predetermined energy level, the capacitance is discharged through the inductance to the active load. The periodicity of the charge and discharge is ensured by the coordinated operation of the switches in the circuit circuits with a given frequency of their synchronous switching. In principle, the proposed amplifier of active electric power consists of a reactive power amplifier (charging circuit) and a reactive power converter into active power of the generated current (dis-charge circuit). The obtained analytical relationships allow one to navigate in the magnitude of the charging voltage on the capacitance, which can be obtained depending on the charge time. Thus, the maximum voltage set by the quality factor of the charging circuit adopted for numerical evaluations requires charging for ~ 0.004 s. However, already 50% of the maximum voltage is reached in a much shorter time ~ 0.0005 s (almost an order of magnitude lower than the charge length to the maximum). The expressions found for the characteristics of the processes in the discharge circuit make it possible to select its parameters in such a way as to provide the highest gain coefficient for the average power of a periodic sequence of current pulses generated in the active load of the amplifier. It is shown that the value of the average electrical power in the load should depend on the ratio of the charge and discharge times, since when the capacitive storage is being charged, the current in the load is zero. It was found that the gain value can exceed the corresponding energy indicator of the power source by an order of magnitude.

An analysis and numerical estimates of induction effects in the metal of a flat circular solenoid located between the branches of an external bifilar coil in a flat inductor system excited by unidirectional currents in the bifilar windings are presented. Such a device, the design of which was first proposed earlier by the authors of this work, is of practical interest for circuits of equipment for magnetic-pulse processing of metals. The use of the considered inductor system makes it possible to minimize the influence of induction effects on electromagnetic processes in the metal of the internal inductor. Numerical estimates are obtained for the induced currents excited in the metal of the inner circular inductor placed between the outer windings of the bifilar coil. It is shown that in the low-frequency mode of acting fields, the time dependence of the excited current is a derivative of the time dependence of the exciting current and the transverse distribution of the current in the metal of the internal inductor is a linear dependence passing through the central axis of the inductor. In the high-frequency regime of acting fields, the time dependence and the radial distribution of the excited current coincide with the corresponding analogs for the exciting current, and the transverse distribution of the induced current is characteristic of a sharp surface effect, when the induced current is displaced to the boundary surfaces of the metal. It is proved that the minimum influence of the fields of the external bifilar on the electromagnetic processes in the internal inductor should be observed in the low-frequency mode, when the spatial superposition of multidirectional induced currents adds up to the zero value of the excited electromotive force of induction. The results of the analysis based on the specific calculations performed are aimed at finding the conditions for the successful technical implementation of the proposed inductor system. The creation of workable models of the proposed inductor systems and experiments to determine the real conditions for their maximum efficiency are seen as very promising in the direction of subsequent research.

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The aim of the research is the analysis and evaluation of the electromagnetic processes characteristics in the proposed flat rectangular system consisting of a thin solenoid-inductor located between the branches of the bifilar, thin-walled multi-turn coils. The analysis of electromagnetic processes and the obtained estimates of the excited currents are carried out. It is shown that with a minimum gap between the windings of the solenoid-inductor and the bifilar, the time functions of the exciting current and the current induced in the bifilar windings are the same, and the amplitude of the latter is maximum and equal to half the current amplitude in the inductor. It was found that the proposed system has a practical invariance of the time shape and amplitude of the induced current in a wide range of variable geometric parameters. The minimal effect of the fields of induced currents on the processes in the solenoid-inductor and the minimum losses when removing the induced signal from the bifilar windings are noted. Physically, the first is due to the asymmetry of the excited magnetic field relative to the plane of the solenoid-inductor, the second is due to a significant decrease in spurious inter-turn capacitance due to the thinness of the bifilar windings. The obtained results allow us to give practical recommendations when choosing design solutions for elements of new circuits of equipment for magnetic pulse metal processing. References 14, figures 2.