Shaping the output pulse of a linear-transformer-driver module

Abstract

We demonstrate that a wide variety of current-pulse shapes can be generated using a linear-transformerdriver (LTD) module that drives an internal water-insulated transmission line. The shapes are produced by varying the timing and initial charge voltage of each of the module's cavities. The LTD-driven accelerator architecture outlined in [Phys. Rev. ST Accel. Beams 10, 030401 (2007)] provides additional pulseshaping flexibility by allowing the modules that drive the accelerator to be triggered at different times. The module output pulses would be combined and symmetrized by water-insulated radial-transmission-line impedance transformers [Phys. Rev. ST Accel.

Impedance-matched Marx generators

“…5(b) is applicable, the peak value of the electrical power delivered by the IMG to a load with impedance Z load is maximized when Z and Z load satisfy the following relations [6,7]: (17)- (22) are satisfied, the IMG is impedance matched to its load; i.e., the peak electrical power delivered by the IMG to the load is maximized. (We do not address here the pulse-shaping technique of Ref.…”

“…The quantity R c is the effective series resistance of a single LTD cavity, L c is the effective series cavity inductance, C c is the series cavity capacitance, R cores is the effective parallel resistance within a single cavity due to its ferromagnetic cores, Z is the impedance of the first transmission-line segment, Z load is the load impedance, τ is the one-way electromagnetic transit time of a single segment, R b is the effective series resistance of a single brick, n b is the number of bricks per cavity, L b is the effective series brick inductance, and C b is the series brick capacitance. The quantity Z c is the effective impedance of a single cavity; the expression given by the figure for Z c is valid when R cores ≫ ½1.1ðL c =C c Þ 1=2 þ 0.8R c [7]. (b) When each cavity is triggered at time τ after the cavity immediately upstream is triggered, the circuit of (a) can be simplified as that given by (b).…”

“…The quantity R LTD is the effective series resistance of the LTD module, L LTD is the effective series module inductance, C LTD is the series module capacitance, and R shunt is the effective shunt resistance of the module due to its cores. The quantity Z LTD is the effective impedance of the ten-cavity LTD module; the expression given by the figure for Z LTD is valid when R shunt ≫ ½1.1ðL LTD =C LTD Þ 1=2 þ 0.8R LTD [7]. When circuit (b) is applicable and the values of Z and Z load are as given by the figure, the LTD module is impedance matched to the load; i.e., the peak electrical power delivered by the module to the load is maximized.…”

“…A linear-transformer-driver (LTD) module is an induction voltage adder that is powered by circuits located within the cavities of the adder [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20]. Since an LTD module can be designed to provide single-stage electrical-pulse compression and impedance matching, such modules are attractive candidates as prime-power sources for nextgeneration pulsed-power accelerators .…”

“…For each cavity, Fig. 3 models the cores as a resistive circuit element with resistance R cores located at the cavity output [7,13,[15][16][17][18][19][20].…”