Pulsed inductive thruster
Pulsed inductive thrusters or
PITs as they are commonly abbreviated are a form of
spacecraft propulsion that uses perpendicular
electric and magnetic fields to accelerate a
propellant. A
nozzle releases a puff of gas (usually
argon) which spreads across a flat
induction coil of
wire about 1 meter across. A bank of
capacitors releases a pulse of electric current lasting 10 microseconds into the coil, generating a radial magnetic field. This
induces a circular electrical field in the gas, ionizing it and causing the ions to revolve in the opposite direction as the original pulse of current. Because their motion is perpendicular to the magnetic field, they are pushed out into space.
Unlike other electromagnetic drives, PIT requires no electrodes (which are susceptible to erosion) and its power can be scaled up simply by increasing the number of pulses per second. A 1-megawatt system would pulse 200 times per second.