Tareq Salameh

Robust Feedback Linearizing Control With Sliding Mode Compensation for a Grid-Connected Photovoltaic Inverter System Under Unbalanced Grid Voltages

A robust feedback linearizing control strategy, based on sliding mode compensation, is proposed for the operation of a grid-connected photovoltaic inverter system under grid faults, characterized by unbalanced voltages, to meet low-voltage ride through requirements. Under normal grid condition, the control system is developed for maximum power transfer from the photovoltaic source to the grid by maximum power point tracking operation of the dc–dc converter, and regulation of the dc-link voltage and the current at the inverter-grid side. Under grid fault, which is unbalanced grid voltage due to voltage dips, the active power is regulated to reduce the current excess and the reactive power is injected to avoid the inverter damage or disconnection, while the dc-link voltage is controlled via the dc–dc converter. A sliding mode compensator is injected into the control system to enhance its robustness to uncertainties. The feedback linearizing control schemes are developed from the grid model at the inverter side and the dc-link model at the dc–dc converter side. The proposed control strategies are experimentally validated on a three-phase grid-connected photovoltaic inverter system and experimental results show that the control system is effective in terms of voltage and power control with smooth transitions between the modes.

Modeling and optimization of hybrid solar-diesel-battery power system

this paper presents results on the simulation, modeling and optimization of an off grid hybrid solar PV/diesel/battery/inverter power system for residential application. The principal objective is to design a standalone renewable energy system to meet the desired electric load with high renewable fraction, low excess power and low cost of energy. Hourly simulations and optimization were performed to determine the performance and cost of the different hybrid power configurations. The results show that the solar PV/Diesel generator/battery/inverter power system offers the best performance compared to PV/Diesel generator/inverter; Diesel generator/battery/inverter and Diesel generator alone. From the total energy produced from the hybrid system, 87.6 % is used to meet all the AC load, 7.8 % is the excess electricity and 4.6 % are the system losses in both the battery and inverter. The proposed hybrid power system is sustainable, economically viable and environmentally friendly: high renewable fraction (53.25%), low excess power (7.8%), low levelized cost of energy (0.286

Dendritic CuO structures synthesized by bipolar electrochemical process for electrochemical energy storage

/kWh), and low carbon dioxide emissions (67756 kg CO2/year).