Investigation on Adjustable Magnetic Pulse Compressor in Power Supply System

摘要

Magnetic pulse compressors, based on magnetic switches, are considered as competitive candidates for high-voltage pulse generation. It is generally believed that the lack of operating-parameter tunability of these devices is currently one of the crucial factors limiting their applications. In this paper, an adjustable high-power magnetic pulse compressor, which is deemed as the key component of a power supply system, is investigated theoretically and experimentally. Dominant parameters of the compressor, including the compression ratio, the saturation time, and the peak voltage, can be regulated, which is beneficial for widening the application areas of power supply systems. Specifically, the prepulse of the magnetic pulse compressor is studied as one of the key parameters. A two-stage magnetic pulse compressor was then setup and when the charging time of the primary source was alternated between 19 and 25 μs, pulses with rise-time of 1 μs were achieved with good repeatability. This in turn verified the tunable capacity of the device. When applied in a solid-state high-voltage pulse generator, the pulse compressor successfully enabled the generation of intense electron-beam with peak power over 5 GW, peak voltage of 380 kV, pulse width over 170 ns, and repetitive rate of 20 Hz. The device has been successfully used for research on plasma science and for driving the sources of high-power microwaves where the requirements on the device often vary substantially. In the latter application, based on the high reliability of the solid-state pulse generator, optical diagnosis has been conducted of the plasma expansion characteristics of the magnetically insulated coaxial diodes cathode, in order to analysis the mechanism of the pulse shortening phenomenon. Experimental results show reasonable agreements with the analyses.