Degree Name

BS in Aerospace Engineering


Aerospace Engineering Department


Kira Abercromby


The goal of this project was to design and build a compensated pulsed alternator, or compulsator, to power the Cal Poly Electromagnetic Railgun Mark 1.1. This project examines the feasibility of implementing mechanical pulsed power supplies for repeatable use with a railgun load for orbital debris hypervelocity testing. The final system architecture chosen was a passively compensated, iron-core, 2-phase, permanent magnet compulsator. The Cal Poly Compulsator will be capable of storing 45 kJ of mechanical energy with a peak operating speed of 5,000 rpm at 190 V. Theoretical calculations resulted in the following predicted electrical performance values: a peak output current discharge of 33 kA, peak output power of 3.3 MW, and a pulse width of 4.3 ms. These values result in moving a 1 g projectile to a final velocity of 410 m/s. Experimental testing and comparison will occur once the system has been assembled. The architecture selection process, description of the mathematical modeling of the system, the mechanical design, and some of the manufacturing processes undertaken during this project are included in the discussion. This paper serves as a compilation of introductory information to assist individuals who are just starting their research into compulsators.