Power Management Using One Cycle Control Strategy for Triple Input Single Output Fly Back DC–DC Converter

Abstract

Traditional multi-input converters have simpler configuration, but they have some disadvantages like multiple primary winding, high voltage stresses across the switches and also transfer of energy to the load occurs only from anyone of the input sources. This article proposes an isolated converter with reduced number of primary winding, and the load can be supplied by the sources either individually or simultaneously. The main objective of this work is to inject power into the grid using a three input single output Fly back DC–DC converter with closed loop control using one cycle controller (OCC) and PI controller. For power management, the inductor current is measured and the duty ratios of respective sources are controlled in such a manner that the average current flowing through the switch is proportional to power delivered by respective sources. In order to maintain the output voltage to be constant, the duty ratio of any one source is to be controlled by using outer voltage controller and inner current controller. Here, the duty ratios of first two sources are controlled by current mode control using OCC and the duty ratio of third source is controlled by using voltage controller with inner OCC current control. Since OCC is a nonlinear technique, only one PI controller is needed by the system. The system has only two sensors, one for measuring the output voltage and one for measuring the inductor current.