Two alternative modes of operation for the current-source flyback inverter are investigated in this paper. The discontinuous conduction mode (DCM), where a constant switching frequency (CSF) control method is applied, and the boundary between continuous and DCM (BCM) that is introduced for photovoltaic (PV) applications in this paper (where a variable switching frequency control method is applied). These two control methods are analytically studied and compared in order to establish their advantages as well as their suitability for the development of an inverter for decentralized grid-connected PV applications. An optimum design methodology is developed, aiming for an inverter with the smallest possible volume for the maximum power transfer to the public grid and wide PV energy exploitation. The main advantages of the current-source flyback inverter are very high-power density and high efficiency due to its simple structure, as well as high-power factor regulation. The design and control methodology are validated by personal computer simulation program with integrated circuit emphasis (PSPICE) simulation and experimental results, accomplished on a laboratory prototype.

The newest technology on decentralised grid-connected PV systems is the "AC-PV Module", which is characterised by a number of clear advantages over conventional large PV systems. Single stage topologies seem to be a rather attractive solution, for these applications, since in generally they are characterised by high efficiency, low cost and simple structure with high reliability due to reduced components count. On the other hand in single-phase AC-PV Module inverters, the power that is transferred to the power network has a large amount of power pulsation at twice line frequency. So a large ripple of voltage and current appears at the PV module output. Taking into account that there is a close correspondence between the power that flows from a PV module and the point of operation, this fact leads to reduced PV power generation. In order to overcome this defect, this paper presents a novel current pulsation smoothing parallel active filter (CPS-PAF) which is independent from the inverter topology and his operation mode. Purpose of the proposed CPS-PAF is the elimination of the low frequency PV current ripple. So the PV module can be operated close enough to the maximum power point and consequently the PV generated electricity power is maximised. The CPS-PAF conception, control and effectiveness are validated by PSpice simulation and experimental results accomplished on a laboratory prototype.

Nowadays, the imperative need for the reduction of Greenhouse Gas (GHG) emissions leads to the wider adoption of environmentally friendly transportation means. As a result, various policies underpinning the Electric Vehicle (EV) deployment are legislated globally, and several technical advances contributing to the electrification of the transportation sector are pursued. In this paper, a comprehensive overview of the current status of the infrastructure utilized for the realization of both conductive and contactless (wireless) charging of an EV battery is conducted. Furthermore, the issue of EV integration in conventional distribution networks, as well as in future power system architectures, is discussed in detail. Particular focus is given to wireless (i.e., inductive) charging. A detailed presentation of the respective standards and charging levels, as well as the magnetic couplers and the compensation network configurations, is carried out. Moreover, innovative concepts such as dynamic and quasi-dynamic wireless charging, as well as future challenges and opportunities, are presented and discussed. Finally, smart control and communication techniques applicable to EV charging are presented in the context of the future Internet of Energy (IoE) concept.

Over recent years the output power of microinverters (ΜIC Module Incorporated Inverter) is progressively pushed to higher levels, following the current PV modules market trends. The interleaved Flyback inverter - under Discontinuous Conduction Mode of operation (DCM) - is an appealing solution for PV applications which are based on MIC technology. This topology provides increased power level for distributed PV generation (DG-PV) exploitation with simple control configuration, high efficiency, and reduced filter size. In this paper the harmonic injection capability is incorporated into the interleaved Flyback inverter for the implementation of an active anti-islanding scheme. A suitable technical solution is proposed in order to bypass the unfolding H-bridge, without affecting the active power generation of the inverter and without requiring any hardware modification. In addition, a mathematical model based on the Instantaneous Power Balance (IPB) theory is presented, being a powerful analysis tool for inverters operating under complete magnetic discharge like the Flyback one (either conventional or interleaved) under DCM or BCM mode of operation. The proposed model predicts accurately the steady state operational behavior of Flyback inverter under current harmonic injection, either in grid-tied or islanding operation. The proposed technical implementation method and mathematical model are verified through simulation and experimental results. Finally, an anti-islanding set-up based on the proposed harmonic injection technique is presented and implemented into the Flyback micro-inverter. The proposed set-up is verified through experimental results on various QF values, as well as for weak grid conditions.

On single stage PV converters the output power has a large amount of power pulsation at twice line frequency, causing PV module voltage and current fluctuation. However, a PV module should operate at a sufficiently small area around the maximum power point, in order to maximize PV generation. To overcome this defect a buffering storage unit between the PV module and the inverter, which performs the well known power decoupling, is inevitable. This paper presents an enhanced configuration of a current pulsation smoothing parallel active filter (CPS-PAF) which permits the elimination of the low frequency PV current ripple with significant smaller capacitor comparatively to the classical configuration. The enhanced CPS-PAF conception, control and effectiveness are validated by PSpice simulation results as well as by experimental results accomplished on a laboratory prototype.