Line type modulators are typically developed for driving klystrons, high power RF tubes, and other high voltage loads that require tight pulse shape control (usually a square pulse with minimal rise/fall times and minimal flat-top ripple).
Line type modulator technologies:
Photos of the power supply system may be seen on the<!A HREF="phsps.html">Ness Engineering SCR Phase Control Power Supply Experience<!/A> page.
More detailed photos of the solid state, command charging switch assembly and resonant charging system can be seen on the<!A HREF="ssmod.html">Ness Engineering Solid State Switching Experience<!/A> page. 520 MW Klystron Line Type Modulator PFN Charging Current and Voltage Waveforms shows the half-sinusoidal PFN resonant charging current waveform (terminated somewhat early by the de-qing process) and the typical "1-cos" PFN voltage waveform associated with command resonant charging ending with a voltage of 71.2 kV on the PFN capacitors. 520 MW Klystron Line Type Modulator Output Current Waveform shows the output pulse shape of the 10 ms flat-top pulse delivered to the load. More details on the technical design and performance of this line type modulator can be found in the published technical papers on the 520 MW Klystron Modulator System and the Command Resonant Charging System for this modulator.
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