Scaling Approach for Sub-Kilowatt Hall-Effect Thrusters

Properly determining the size and predicting the performance of a Hall-effect thruster (HET) is an essential process in the early phase of thruster design. In this paper, the scaling relations for a sub-kilowatt HET were derived in the form of linear equations from the physical relationships and the approaches found in previous studies. Because the anode power and voltage are major constraints in thruster design, the equations were given as a function of those parameters. The linear coefficients in the proposed scaling equations were determined from linear regression analysis on the test data from low-power HETs that consume less than 1.35 kW. A large discrepancy was shown between the coefficients and the values obtained from test results from a wide power range due to the losses in small thrusters. A low-power HET that consumes 360 W and applies 300 V at the anode was designed on the basis of the proposed relationship. To validate the thruster design using the proposed relations, the thruster was tested and the results showed that the measured thrust fell within the 95% prediction band.