DC Integration of Residential Photovoltaic Systems: A Survey

Abstract

PV systems are penetrating the energy generation market rapidly. PV system output strongly depends on environmental conditions. As a result, the utilization of power electronic converters is mandatory. On the other hand, most modern loads, from small to big ones, are based on dc, similar to the renewable sources generating dc. Hence, wide adoption of residential dc microgrids (RDCμGs) based on PV energy would be a trend soon, following modern developments in energy-efficient buildings. This paper targets power converters for the integration of PV systems into RDCμGs. It considers two main classes: high stepup converters for PV module-level, parallel optimizer, applications, and non-isolated buck-boost converters for the PV string, series optimizer, applications. Due to the importance of the PV topic, a significant number of topologies have been introduced in the literature. However, not all topologies attracted the interest of the industry. This review paper considers PV converters used in industry or demonstrated in academia at a high technology readiness level with comprehensive experimental justification. This allows us to focus this review on the most valuable solutions and to provide a guide for both industry and academic readers. In the end, future trends in industrial PV systems and power converters are discussed.

Implementation of New Optimal Control Methodology of Quazi Z-Source Inverter Based on MPC

“…Use Eqs. ( 9) & (10) Set the THD & qZSI Power losses final optimal state is x opt 42: end procedure MMPC is based on expanding the number of the checked switching states from 9 states in [33] to 15 states in the proposed scheme, accordingly, the number of For-Loops which is used to select the optimal operating switching state should be increased resulting in increasing the computation time. However, in this study, the computational burden has been reduced by utilizing calculation loop optimization by reducing the number of switching states in the loop and calculation loop unrolling.…”

“…But this also increases the cost and complexity of the control circuit and components. To overcome these problems, some researchers suggested using single-stage converters without transformers, based on new topologies called multi-level inverters [6], [7], [8], [9], [10]. These inverters use many power devices connected by passive and active switches, which require complex control circuits.…”

Survey of Topology Morphing Control Techniques for Performance Enhancement of Galvanically Isolated DC-DC Converters

“…Residential PV systems suffering from partial shading of PV modules need interface converters capable of global maximum power point tracking [97]. This feature requires those converters to ensure a wide input voltage range that could be achieved at a low cost using TMC [83].…”

High-Performance Buck-Boost Partial Power Quasi-Z-Source Series Resonance Converter

“…However, later research showed they are equivalent to a full power boost converter in terms of stress of the main components and thus can not be considered true PPCs [34]. Hence, dc-dc topology used in a PPC must have some kind of galvanic isolation, either by a transformer or using a flying energy storage component (capacitor or inductor) [33], [35], [36].…”