Current sharing of paralleled DC-DC converters using GA-based PID controllers

We demonstrate a concept for pulse-width modulation (PWM) control of a parallel DC-DC buck converter, which eliminates the need for multiple physical connections of gating/PWM signals among the distributed converter modules. The proposed control concept may lead to easier distributed control implementation of parallel DC-DC converters and distributed power systems. For equipment with significant power requirement, the traditional single power supply may not be adequate. Many power supplies with parallel regulation control can be used to solve this problem. This paper proposes a Proportional-Integral-Derivative (PID) controller to control paralleled DC-DC buck converters and current sharing is achieved. A genetic algorithm (GA) is employed to derive optimal or near optimal PID controller gains. Both simulations and experimental results are provided to verify the theoretical analysis through an experimental prototype of paralleled DC-DC buck converters. (C) 2009 Elsevier Ltd. All rights reserved.