  The weighted voltage mode control represents a method for control of multiple
outputs DC-DC converters. Accordingly, the weighted control redistributes the
error among the outputs of these converters, and the regulation error can be
reduced by adjusting the weighting factors. But the problem is that most
designs are performed on the trial-and-error basis, and the results were rather
inconsistent. Also, in conventional mathematical approaches, this factor is
designed for converters by given parameters. In this paper, three optimization
algorithms namely Imperialist Competitive Algorithm (ICA), Particle Swarm
Optimization (PSO) and Ant Colony Optimization (ACO) are proposed for a quick
and accurate estimation of the optimal weighting factors and improve the amount
of regulation on outputs of multiple outputs forward DC-DC converters.
Furthermore, Fuzzy Logic Controller (FLC) is utilized to minimize the total
steady-state error and improve transient characteristics by controlling the
duty cycle of the PWM controller. Simulations have been performed in several
cases and results show that the proposed method improves the outputs cross
regulations in multiple outputs forward DC-DC converters significantly. ICA
based weighting factor estimator has higher speed and accuracy in comparison
with two other presented algorithms (ACO and PSO) and so is more effective in
comparison with them.
