These circuits show how to use the SSN Iterative SWITCH algorithm to simulate 6, 12 and 18-pulse rectifiers with low inductance for the transformer, typical of onboard aircraft power systems.
Figure 1: 18-pulse diode rectifier found in aerospace applications
These apparently simple rectifier circuits come from the complete Global Challenger Express model discussed in . If you simulate the 18-pulse rectifier only with the SimPowerSystems Backward Euler solver (the most stable SPS solver), with the lightest of specification loads, you obtain important glitches that are avoided with the SSN solver, as shown in the figure below.
Figure 2: Comparison between SSN and SPS (Backward Euler) solvers for the 18-pulse diode rectifier under light load conditions.
 L. Montealegre Lobo, C. Dufour, J. Mahseredjian, "Real-time Simulation of More-Electric Aircraft Power Systems", Proceedings of the 15th European Conference on Power Electronics and Applications (EPE’13 ECCE Europe), Lille, France, Sept. 3-5, 2013