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To evaluate the performances of electronic power converters for photovoltaic (PV) applications, a PV energy source or a PV emulator is required. The PV emulator has the advantage of being low cost, portable and reconfigurable. With a PV emulator, it is possible to reproduce the current vs. voltage characteristics of PV sources that depends on solar irradiance and temperature. Moreover, it is possible to fairly compare advantages and drawbacks of different MPPT algorithms. In this paper a dynamic photovoltaic emulator based on a buck converter with an average current mode control loop is proposed. The emulator algorithm to track the desired operating conditions is simulated using Matlab/Simulink for a constant step size. The simulation results verified that the algorithm has improved dynamic and steady-state performance.

International audience; Broadband power-line communication (PLC) technologies are one of the main parameters of digital convergence voice-data-video in the home environment. These technologies use the power-line network as a propagation and a communication medium. Its transmission quality depends on the frequency behavior of the propagation medium and the connected household electrical appliances. The impedance of those devices and noise levels has a great impact on the PLC systems. In this paper, a simulator for indoor power-line channels is presented. In this paper, a new approach is presented for modeling temporal variations of noise and channel on indoor power lines. A three-conductor power cable (phase, neutral, and ground) is modeled by a circuit of four elements (resistor R, inductor L, capacitance C, conductance G). The RLCG parameters are deduced from the impedance measurement in open circuit and in short circuit. The cable model is validated in time and frequency domains. Then, the temporal variation of periodic noise is modeled by a stochastic approach. The global model, combining both channel and noise variations, is validated by comparing SPICE simulation and measurement results.

This paper presents an electric line study of microgrid. To optimize the management of electric sources, generally a proposed solution is the load shedding. To achieve it, the power line communication (PLC) is often used to communicate when it is not possible to add cables. Such technologies use the power line network as a propagation and communication medium. The network quality depends mainly on the power grid topology, but also on the connected household electrical appliances that have a large impact on the PLC systems due to their impedances and noise. In this paper, we propose a new simulation program with integrated circuit emphasis (SPICE) approach for modeling both the electromagnetic (EM) disturbances generated by a printer and the power network. First, the high-frequency power cable characteristics are extracted from S parameter measurements. Then, the model of EM noise generated by a printer is deduced from time-domain measurement and integrated to the SPICE simulator by means of its Laplace transform. Simulation and modeling results of a simple power grid are given in terms of insertion loss evaluation (S21 parameter). A validation of the EM noise model is performed by means of a comparison between simulation and measurement results in frequency domain at several points of a simple power network. The present approach allows the prediction of EM interference generated by all household devices at any access points of a power line network without carrying out a systematic measurement.

High-power electrical drives, subsystems, and equipment mounted on board of rolling stock make the internal environment potentially harsh from the point of view of electromagnetic (EM) field emissions. In particular, at low frequencies, electronically controlled power drive systems behave as effective emission sources. This paper deals with characterization of electromagnetic field radiated from D.C. railway systems. The D.C. railway system of Tunis’s urban electric metro is described. The magnetic field is measured at different points inside and near the moving D.C. train. Measurement results are presented and analyzed. Analysis of measurement results shows that, within frequency range 100kHz-20MHz, the radiated magnetic field is coming from power electronic systems embedded on the train. In particular, choppers, D.C. motors and their connecting cables represent the most important emitting source of magnetic field in the D.C. tramway.

Broadband Power Line Communication (PLC) technologies represent a main factor of the development of the digital convergence voice-data-video in the home environment. Such technologies use the power line network as a propagation and a communication medium whose quality depends mainly on the power grid topology, but also on the connected household electrical appliances which impedance and noise levels have a great impact on the PLC systems. In this paper, we propose a new approach for modeling temporal variations of noise and channel in indoor power line. Three-conductor power cable (phase, neutral and ground) is modeled by a RLCG circuit. RLCG parameters are deduced from the impedance measurement seen by the generator in open circuit and in short circuit. Cable model is validated in both time and frequency domains. Then, the temporal variation of periodic noise is investigated. The global model combining the channel model and the noise variations is validated by comparing simulated results with measurements.