Annual Energy Outlook 2008 With Projections to 2030

Power processing systems will be a key factor of future photovoltaic (PV) applications. They will play a central role in transferring, to the load and/or to the grid, the electric power produced by the high-efficiency PV cells of the next generation. In order to come up the expectations related to the use of solar energy for producing electrical energy, such systems must ensure high efficiency, modularity, and, particularly, high reliability. The goal of this paper is to provide an overview of the open problems related to PV power processing systems and to focus the attention of researchers and industries on present and future challenges in this field.

Reliability Issues in Photovoltaic Power Processing Systems

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Bayesian Survival Analysis.

Control in Power Electronics : selected problems

Reliability assessment of photovoltaic power systems: Review of current status and future perspectives

D-STATCOM for harmonic mitigation in low voltage distribution network with high penetration of nonlinear loads

Comparative study of different PV modules configuration reliability

In this paper, a four-leg matrix converter is proposed as the power conversion core for aircraft ground power unit (GPU) applications. This structure allows easy management of unbalanced and nonlinear loads with minimal disruption of the power supply operation. A hybrid repetitive-traditional control system is proposed to regulate the output voltage of the GPU. This solution reduces the steady-state tracking error, maintaining fast dynamic characteristics, and increases the stability of the converter compared to conventional approaches. Simulations and experimental results from a 7.5-KW converter prototype are presented to verify the operation of the proposed configuration and to prove the effectiveness of the solution.

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A Four-Leg Matrix Converter Ground Power Unit With Repetitive Voltage Control

This paper presents a D-STATCOM for reactive power compensation in a distribution system that uses inductive energy storage element connected to the grid via a matrix converter (MC). The MC is controlled using model predictive controller (MPC) technique. The D-STATCOM will provide load compensation without using electrolytic capacitors. Electrolytic capacitors have well-known failure modes. Therefore, reactive power compensators that use a voltage-source inverter (VSI) with electrolytic capacitors as energy storage involve periodic replacement and monitoring constantly. Consequently, this will incur an increase in the cost of the traditional approaches of load compensation significantly. MC system controlled using MPC provides reactive power compensation by controlling the output inductors and the input reactive power. Therefore, the proposed compensator which is based on MC and inductive energy storage has a longer expected service life and more reliability compared with VSI based compensators.

Capacitor-less D-STATCOM for reactive power compensation

Power quality in an AC power distribution system is reduced by nonlinear loads which draw non-sinusoidal current. When this distorted current interacts with the line impedance of the distribution network (the grid), the system voltage becomes distorted which could adversely affect other electrical devices connected to the grid. In the traditional grid, this is compensated at the substation by the utility. Adding PV into the distribution system can complicate the situation when power flow reverses due to excess generation resulting in back-feeding into the grid. It has been proposed that the photovoltaic inverter should actively improve the power quality by compensating harmonic and reactive current. However, this adds complexity and cost to the inverter as well as reduces the inverter reliability. To maintain high power quality in the distribution system, it is necessary to develop a means to compensate for the reactive and harmonic currents locally. This paper investigates the use of a distribution static synchronous compensator (D-STATCOM) for harmonic power compensation in a distribution network. The proposed topology is based on a matrix converter topology (MC) which is controlled using model predictive control (MPC) which enables inductive energy storage instead of requiring electrolytic capacitors that have well-known failure modes. Compensating the harmonic current in the distribution system improves the overall reliability of the grid. Simulation is performed using MATLAB/Simulink to investigate the performance and capability. It is envisioned that the device can be deployed and dispatched by the utility as needed in the distribution network to prevent upstream-propagation of the harmonic current, which could lead to transformer overheating and other deleterious effects.

Wesam Rohouma

Papers

D-STATCOM for harmonic mitigation in low voltage distribution network with high penetration of nonlinear loads

Comparative study of different PV modules configuration reliability

A Four-Leg Matrix Converter Ground Power Unit With Repetitive Voltage Control

Capacitor-less D-STATCOM for reactive power compensation

D-STATCOM for a Distribution Network with Distributed PV Generation