Science and Engineering of Electric Propulsion

Electric propulsion has become popular nowadays owing to the trend of miniaturizing the size and mass of satellites. In this talk we will discuss some recent trend, advances and perspectives of electric propulsion in both low-power and high-power limits.

One of main drawback of the most popular approach, Hall thrusters, is that their efficiency and thrust-to-power ratio significantly deteriorate when its size and power level are reduced. We will discuss some alternative approach—a low-power (<50 W), lightweight (~100 g), two-stage propulsion system. The system is based on a micro-cathode arc thruster with magnetoplasmadynamic second stage (mCAT-MPD), which achieves the following parameters: a thrust of up to 1.7 mN at a TPR of 37 mN/W and an efficiency of about 50%. This thruster, in addition to “traditional” inverse, displays the anomalous direct (growing) “TPR versus specific impulse Isp” trend at high Isp values and allows multimodality at high efficiency.

In the high-power limit, multiple configurations of air-breathing thrusters are currently considered. This talk will outline state of the art and will present some new development such as scramjet configuration that can significantly reduce the drag by avoiding compression. In addition, concept of air—breathing plasma thruster without neutralizer will be discussed.