الفهرس 
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Abstract
In a world of increasing energy demand, it is imperative to come up with innovative solutions to reduce energy use or looking for another source. Moreover, the rapid population growth all over the world has resulted in large escalation of demand for fresh water.
This thesis proposes a solution for both energy and water problem by using electricity produced by solar panels in desalination applications. A desalination system driven by a hybrid power supply system in Nikhil region, Sinai desert, Egypt is presented.
Reverse osmosis is rapidly becoming the most suitable choice for the desalination plant because of the less power consumption. Thus, the reverse osmosis is used in this study in Nikhil region. The feasibility of replacing the main power supply with hybrid photovoltaic battery (PVB) system is investigated. Due to the intermittent nature of solar energy, PVB power source have been presented.
PVB-RO system to produce potable water in Nikhil region consists of a PV array, dc-dc boost converter, batteries, battery charger controller, three phase pulse width modulation (PWM) inverter, LC filter and loads consisting of induction motors as inductive loads and lamps as resistive loads.
The system includes two power sources and power electronics interface to drive the three phase induction motors coupled to reverse osmosis (RO) unit pumps. PV array is connected to dc link through dc-dc boost converter. The duty cycle of the converter is continuously adjusted to operate the PV array at its maximum power point. The adjusting of the duty cycle is achieved by a Perturb and Observe (P&O) algorithm. The battery is connected to the dc link through a dc-dc bi-directional buck-boost converter.
The control action is carried out by comparing the dc bus reference value with the present value then the battery will provide the power instantaneously to maintain the bus voltage when the irradiation or the temperature is changing according to the climate in Nikhil region to insure a constant voltage at the inverter’s input. The load side PWM inverter will generate high frequency harmonics in the output ac voltage which supplies the three phase induction motors with ac power.
Sizing of the PVB-RO desalination system depends on many factors: climate of site location, the energy generated from the PV module based on irradiation, total power and energy consumption of all loads. In addition, the cost effectiveness analysis of PV system is investigated.
Computer simulations are carried out by using Matlab/Simulink software environment in order to confirm the system operation under steady-state and transient conditions. The simulated system has included the maximum power extraction algorithm, dc-dc converter controller, and battery current controller. The results obtained from the simulation of the system illustrated that the system has the ability to supply the RO plant under different climatic conditions.