A pulse-amplitude-synthesis-and-control (PASC) inversion system for single-source diagonally connected MHD generators

Abstract

In this paper, the problem of power waveform synthesis using the pulse-amplitude-synthesis-and-control (PASC) technique to produce a desired output from a single DC source is introduced. Although the specific example discussed here is for a diagonally connected magnetohydrodynamic (MHD) generator, the technique can be applied to any single terminal pair source, with appropriate modification in power extraction interface and computer control program to match source and load impedance characteristics. A power inverter is described which directly synthesizes (under computer program control) an approximate sinusoidal output using nearly uniform pulse heights and widths, from a single, two terminal DC source. The mechanism for pulse generation uses a bank of transformers whose primary windings are sequentially-in-time connected in parallel in an overlapped pulse fashion across the two terminal DC source and whose secondary windings are connected in series with the load. Both triangular and sinusoidal control signals give triangular and sinusoidal like outputs respectively, under open loop control, with the quality and voltage output increasing with the number of levels of synthesis approximation. >