So I am modelling an Earth - Mars low thrust trajectory in a simple manner. I'm telling my model to not model any trajectories where the spacecraft is moving any more than 200 m/s quicker or slower than the planet upon rendezvous. This is just for the conic section. So when the spacecraft arrives at Mars, I calculate its speed relative to the planet at that point, and I am treating that as the hyperbolic excess speed (V_infinity), which is constrained to be less than 200m/s. Now, I am getting trajectories that fit the criteria, and they happen to burn very little fuel throughout the journey - my question is, is this physically possible, is it real? Is it even desirable to have low arrival C3's? All the literature I read have arrival C3's/V_infinities in the order of km's/s (or km's^2/s^2) but I have it constrained to mere m's/s. I would have thought, intuitively, the closer the s/c can get to matching the planets velocity, the less of a burn needed for orbital capture, ergo fuel saved?
My orbit looks like a spiral thats made 2 revolutions of the sun. Time of flight, approximately 1400 days. Delta - V is much larger than a chemically propelled ship, but that's OK I guess as the fuel usage is lower. Plotting Mars as an elliptical orbit, not just circular. Hope that helps.