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In the context of energy conversion from renewable sources to distribution grids (insulated or not), a converter is often required to transfer energy from a low voltage source towards three-phase grids. This paper presents the HW design, the simulation results, and the conversion performance of a CSI converter intended to interface low-voltage renewable sources to three-phase grids. The main focus of this paper is to obtain the best performance in terms of voltage increase towards the output stage while maximizing the conversion efficiency. In comparison with the currently used energy conversion systems for small photovoltaic systems, hereafter some solutions were adopted to level and maximize the energy flow from the source to the DC-link and improve the quality of current supplied in terms of harmonic distortion. The proposed system is composed of two conversion stages: the first, voltage-to-current, the second current-to-current via a three-phase CSI bridge modulated with the SVM technique. The stages are not completely decoupled from an electrical point of view; therefore, in order to mitigate the effects of these interactions, synchronization strategies have been adopted. [ABSTRACT FROM AUTHOR]

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Integrating solar energy in electric vehicles (EV) is expected to play a dominant role in the decarbonization of the transportation sector as well as reducing the charging costs. These integrated photovoltaic automobiles are particularly adapted for urban driving that is to say the driving range is limited. On that account, the use of a feasible energy storage system is necessary to boost the driving mileage. This paper uses a hybrid energy system, containing a battery as the main storage device and a supercapacitor (SC) as a backup. This combination was suggested in order to negate the former's deficiencies. The use of a hybrid energy source leads to the necessity of introducing a robust power management strategy to guarantee the optimal power flow in electric vehicle components. An artificial neural network is then trained with model calculation for the power management approach for the traction chain. The results of the simulation indicate that the proposed system is efficient in improving the energy management of the vehicle. Moreover, the system's simplicity could potentially make it easier to implement in real-time using a DSP or a DSPACE platform. [ABSTRACT FROM AUTHOR]

The paper presents a thermal analysis of an axial flux synchronous permanent-magnet machine (AFSPM) with a core of soft magnetic composite (SMC) material. We obtained the temperature distribution by using a coupled thermal and fluid dynamic finite-element model. The study considers two 2-D approaches and compares their results to experimental tests. Index Terms--Axial flux machines, electrical machines, finite-element analysis, thermal analysis.

This paper introduces a novel brushless, single winding and single stator, dual PM rotor axial-air-gap machine capable to deliver independently torque at the two rotors by adequate dual vector control. The proposed topologies, the circuit model, controlled dynamics simulation and preliminary 3D FEM torque production on a case study constitute the core of the paper. The proposed dual mechanical port system should be instrumental in parallel (with planetary gears) or series hybrid electric vehicles (HEV) aiming at a more compact and efficient electric propulsion system solution.

This paper investigates the thermal behavior of axial flux synchronous permanent-magnet machines (AFSPMMs) through a 3-D thermal-magnetic finite-element analysis (FEA). This paper offers a systematic approach to magnetothermal FEA. The considered axial flux machine is wound on a soft magnetic compound core. The computation of thermal field is performed via a coupled thermal and fluid-dynamical model based on FEA, where the thermal sources are obtained from a dc current flow model and a magnetostatic model. This paper includes an overview of the finite-element method (FEM) model implementation. Simulation results are presented, and, to validate the model, the simulated surface temperature rise of the motor parts is compared by experimental data. Index Terms--Axial flux machines, electrical machines, finite-element analysis (FEA), finite-element method (FEM), fluid dynamics, thermal analysis.

Choosing a dc/ac converter is mainly a compromise among three major issues, namely: 1) efficiency; 2) waveform quality; and 3) cost. This paper considers a zero-current-switching (ZCS) current-source inverter (CSI) as a viable choice for many applications. It features low conduction and switching losses, inherent output filtering, capability of withstanding short circuits, and the opportunity to use thyristors. Despite these promising characteristics, this inverter exhibits a nonlinear relationship between the modulation index and the output current. Moreover, the resonant modes that are generated by the load-filter interaction must be damped. Since the previous aspects require a proper control law, a model of the system is very useful for defining and tuning a control structure. Thus, after providing a functional overview of the ZCS dc/ac CSI, this paper formulates a large-signal model and then derives and simplifies the averaged one. Numerical data are used to validate the models that are obtained. An active damping control for a motor drive is defined and tuned by means of the simplified averaged model, and its effectiveness is numerically validated. Experimental results conclude this paper. Index Terms--Current source, power converter, pulsewidth modulation (PWM), resonant link converter, zero-current switching (ZCS).

This paper illustrates the operation of a tubular-machine drive as a linear generator for a heave-buoy wave energy conversion. Linear generators, which are adopted in marine power plants, offer the advantage of generating without introducing any conversion crank gear or hydraulic system. The use of a tubular-machine topology allows the electromagnetic thrust density to be improved. This paper briefly summarizes the principles of marine wave buoy interaction and reports the design analysis and control of a permanent-magnet (PM) synchronous tubular linear machine based on a scaled generator prototype and on a rotating simulation test bench. Index Terms--Heave buoy, linear synchronous generators, marine energy, tubular generators.

The current source inverters may become direct competitors of the voltage source inverters thanks to the voltage control techniques. The paper proposes an improved voltage control technique for current source inverters, that chooses the current vectors relying on bang-bang controllers. This technique is compared to a well-established one using current space vector modulation and synchronous-frame proportional and integral controllers. The presented controller is explained and validated by means of off-line as well as real time simulations and experimental tests. The numerical results prove that the proposed control technique produces less distorted voltage waveforms in terms of total harmonic distortion and spectrum. According to the real-time simulations performed the proposed control technique is computationally less expensive than the benchmark. Finally, the experimental results obtained confirm the feasibility of the proposal. Index Terms--Current source inverter (CSI), power conversion, pulse width modulated power converters, voltage control.