Distributed power flow control using cascaded multilevel isolated bidirectional DC–DC converter with multi‐phase shift modulation

Abstract

This study proposes a cascaded multilevel isolated bidirectional DC-DC converter (CMIBDC) suitable for large capacity energy storage applications. Compared to conventional IBDC, the proposed converter has higher power-handling capacity distributed among multiple cascaded HV and LV bridges. The HV bridges are cascaded through a high-frequency transformer with a common DC bus. On the other hand, the LV bridges are directly cascaded with isolated DC storage batteries. Effectively, the CMIBDC requires only a single DC input to store the energy in multiple battery units. A multi-phase shift (MPS) modulation scheme has been introduced which provide wide range of power flow control. The MPS modulation shapes the highfrequency link AC current with low THD thus reducing high-frequency losses. Detailed operating waveforms of the proposed CMIBDC converter in different modes are presented. The performance of the proposed converter and modulation scheme has been demonstrated through PSCAD/EMTDC simulation and validated experimentally using Spartan 3AN FPGA processorcontrolled CMIBDC.

Reconfigurable solar photovoltaic systems: A review

“…As a result, the overcurrent protection coordination and the operation of voltage regulators may get affected. Suitable protection methods should be implemented for feeders to overcome these issues by considering feeder basis studies and allowing bidirectional power flow as proposed in the literature [ 21 , 22 , 23 , 24 ].…”

Implementation of Non-Isolated Zeta-KY Triple Port Converter for Renewable Energy Applications

“…An isolated three level dc power conversion was proposed by Dusmez et al [7] that was cost effective, but the number of components used was more and had different levels of power conversion. In addition, in [8,9], the cascaded H bridge structures were proposed for multiple energy sources, but the power conversion process involved multiple dc links in their converters and increased the overall volume of the dc converter. In other proposed research works [1][2][3][4][5][6][7][8][9], multiple energy sources were fed to dc-dc converters either to feed dc or ac loads as shown in Figure 1a.…”

Common‐ground non‐isolated high‐gain DC/DC converter for low powerdistributed generation photovoltaic systems

“…So, high step‐up converters are remarkably used in renewable energy systems to provide conversion system requirements. Renewable energy systems can reach to DC or AC distribution network voltage levels and extract the maximum power of the source at any condition using these converters [1], which can be used in both isolated or non‐isolated forms [2–4].…”

“…Isolated topologies always need a transformer that creates galvanic isolation and high voltage gain for the converter. However, the transformer often increases the size, cost and weight of the converter [4, 5]. Also, the transformers apply some leakage inductances, and copper and iron losses into the circuits.…”

“…The voltage multiplier topologies also have an excellent high voltage ability and simplicity alongside high voltage stress on active and passive components in several cells and high input current ripple problems [22]. The voltage lift topologies as another type of step‐up converter have a lot of passive components, high voltage stresses, and low power capability versus extra high‐gain ability [3, 4]. Finally, hybrid types (proposed converter type) of step‐up DC/DC converters are proposed to combine benefits and reduce disadvantages [23, 24].…”