Bidirectional DC-DC Converter Circuits and Smart Control Algorithms: A Review

Abstract

The entire article has been dedicated to cover the current state-of-the-art in Bidirectional DC-DC converter topologies and its smart control algorithms, identified the research gaps and concluded with the motivation for taking up the work. It covers the literature survey of Bidirectional buck-boost DC-DC converters and control schemes are carried out on two aspects, one is on topology perspective and another one is on control schemes. Different topologies with and without transformers of bidirectional DC - DC converters are discussed. Non-isolated converters establish the DC path between input and output sides while transformer based converters cancels the DC path in between input and output sides since it introduces AC line between two DC lines just like in flyback converter. Transformer less converter is preferred when there is no much protection needed for load from high voltage levels also these converters are used in high power applications. The Bidirectional DC-DC converter can switch the power between two DC sources and the load. To do so, it has to use proper control schemes and control algorithms. It can store the excess energy in batteries or in super capacitors. In contrast, isolated topologies contain transformers in their circuits. Due to this, it offers advantages like safeguarding sensitive loads from high power which is at input side. In addition to it, multiple input and output ports can be established. With the isolation in DC-DC converters, input and output sections are separated from electrical stand point of view. With isolation, both input and output sections will not be having common ground point .The DC path is removed with isolation due to usage of transformer in DC-DC converters. In contrast to its features, it is capable to be used in low power applications since transformer is switching at high frequency, the size of the coil reduces and hence it can handle limited rate of current. The bidirectional DC-DC converters are categorized based on isolation property so called isolated bidirectional converters. Features and applications of each topology is presented. Comparative analysis w.r.t research gaps between all the topologies is presented. Also the scope of control schemes with artificial intelligence is discussed. Pros and cons of each control scheme i.e. research gaps in control schemes and impact of control scheme for bidirectional DC-DC converters are also presented.

A novel control technique for various modes of grid-connected PV system to improve power quality.

“…The other customers, thereby reducing traditional means of power generation, can also utilize the stored power [3]. The bidirectional converter for grid application is given in [4][5][6]. A typical stand-alone PV system consists of a solar module and a battery connection, thereby increasing the capital cost of the PV system as compared to the other energy sources.…”