Design, simulation and implementation of two phase interleaved bi-directional DC-DC converter

Abstract

The bi-directional DC-DC converter has many applications, such as in hybrid vehicles, solar inverters, in power supplies for microprocessors etc. A bi-directional dc-dc converter can be alternately operated as a step down converter in one direction of energy flow and as step up converter in reverse direction of energy flow, which is from source to load and load to source. A high power supply using a single converter is not preferred as it leads to high ripple in output voltage and current, thus requiring large value of inductor and filter capacitor. To overcome these limitations multiphase interleaving technique is used in bi-directional DC-DC converters i.e. connecting the converters in parallel with the switching instants equally distributed among them. This paper presents the simulation and implementation of two phase bi-directional dc-dc converter.

Interleaved Switched-Capacitor Bidirectional DC-DC Converter With Wide Voltage-Gain Range for Energy Storage Systems

“…In addition, the current ripple rate of the output current is 17.65%. According to (20), the ripple rate of iL1 and iL2 is 53.57%, and the ripple rate of ilow is 17.86% theoretically, which are in accordance with the experimental results. The conclusion that the current ripple of ilow is much lower than the current ripple of iL1 and iL2 can be obtained.…”

“…In addition, this converter requires a complicate control scheme to balance the flying-capacitor voltage. The interleaved bidirectional DC-DC converter in [20] can reduce the current ripples in the low-voltage side, but it still has the disadvantages including the small voltage gain range and the high voltage stress across the power semiconductors. The interleaved bidirectional DC-DC converters in [25] - [27] have achieved a high voltage-gain, but the maximum voltage stress across the semiconductors of these converters are 2Uhigh/3, Uhigh and Uhigh+ Uhigh(1-d) respectively, rather than Uhigh/2, which will increase the switching losses and reduce the conversion efficiency.…”

“…Besides, the converter in [27] can only achieve the inductor currents balance when the duty cycles are d=0.5, and the inductor currents of the converter in [25] are unbalanced when Db is not equal to 2Da. Regarding the proposed interleaved bidirectional DC-DC converter, the number of main components is equal to that of the converter in [25] , the voltage stress across all semiconductors and capacitors is Uhigh/2, and its voltage gain is higher than that in [14] and [20] . In addition, the inductor currents and the capacitor voltage self-balances can also be obtained within the full duty cycle range, in both step-up and step-down modes.…”

“…Unfortunately, the drawbacks including the narrow voltage conversion range, the high voltage stress and extreme duty cycles of semiconductors make them not suitable for energy storage applications. Though the conventional two-phase interleaved bidirectional DC-DC converter in [20] can reduce low-voltage side current ripples, but this converter still has disadvantages including the narrow voltage conversion range and the high voltage stress for power semiconductors. The voltage stress of power semiconductors of the bidirectional three-level DC-DC converters in [11] , [12] is half that of the conventional two-phase interleaved bidirectional DC-DC converter, but its voltage-gain range is still narrow.…”