FITF-PDM: Unified controller design for non-isolated bidirectional DC-DC converter

Abstract

High quality and reliability of distributed power systems (DPS) play the major role in the telecommunications, industries, and home applications. The controlling of bidirectional power flow with the varied input and output voltage is the major issue in the distributed power systems due to the low settling time and the harmonics generated in them. The control signal provided to the switching devices used in the DC-DC converter topologies is responsible for controlling the power flow. This paper presents the enhanced controller that receives the feedback signal as the input and generates the pulses necessary for the switching devices in the converter. The modeling of the feedback signal with the feedback-integrated transfer function (FITF) provides the pulse density-modulation (PDM) pulses to the switching section. The DC-DC converter uses the DPS as front end, and this is a microgrid system. The FITF-PDM reduces the losses in the switches and improves the output voltage level of the isolated bidirectional DC-DC converter with the minimum settling time. The employment of zero current transition (ZCT) with the FITF-PDM pulses boosts up the input voltage level to control the bidirectional power flow. The variations in the pulse density with respect to the variations in the feedback signal (error signal) are responsible for the update of the controlling function. The proposed FITF-PDM is processes in simulation and compared with the existing control structures in terms of regulation efficiency assures the effectiveness of proposed DC-DC modeling in the real-time applications.