Power Supplies

The main power supply for the PHPP facility consists of a 20 banks of 16 26 μFarad, 10 kV capacitors, arranged in an L-C pulse forming network (PFN). The setup can be adjusted to produce rectangular current pulses ranging from .5 to 2 ms and current levels up to 50 kA. SCR thyristor switches capable of 1 Hz repetitive operation initiate the discharge in pulsed thrusters yielding a pulse risetime of 100 μs. Ballast resistance is maintained with a water-cooled tubular steel resistor in series with the thruster load. Current transformers, voltage probes and safety interlocks are configured in the power supply system. A computer-controlled control panel allow automatic operation with thruster firings as frequent as 1 shot every second.

Additionally, the PHPP facility shares a 21 kW (35 V - 600 A) Rapid power supply with the Steady-State MPD facility. The PHPP facility also features American Reliance and EMCC external power supplies for regular use.

Previous Use

Previous Use The PHPP facility has been used for thruster performance measurements, lifetime and erosion studies, thruster scaling studies, plume characterization, plasma dispersion relation measurements, and plasma turbulence studies. A high-power pulsed thruster performance characterization study with hydrogen and deuterium propellants, has yielded unprecedented thrust efficiency levels of 75% at specific impulses exceeding 10,000 s.