فهرست مطالب عرفان رجائیان

Renewable energy sources can provide a suitable solution to meet the increasing load demand. Therefore, based on the objective functions and according to the structure of the distribution network, and the variety of solar radiation intensity, ambient temperature, and wind speed in different network nodes, the location, and capacity of renewable sources should be determined optimally. As in the distribution networks, the voltage stability of the lines and the voltage profile of the buses are usually not in the desired condition, so improving the voltage stability can be considered as one of the main goals in the allocation and capacity determination of renewable sources. For this purpose, in this paper, the optimal location and capacity of hybrid distributed generation sources including photovoltaic power plants, wind farms, diesel generators, and energy storage systems are done. The objective functions include reducing the probability of loss of power supply, minimizing the total net present costs, and improving the network voltage stability. For this purpose, based on annual information of radiation intensity, wind speed, temperature, and profile of residential, commercial, and industrial loads, optimal allocation and capacity determination of hybrid distributed generation are done in IEEE 33-bus radial distribution system using multi-objective genetic algorithm.

The inverter is one of the main components of photovoltaic power plants. Since the power output of the power plant is directly related to the inverter's performance, the inverter losses have an important effect on the generation and efficiency of the photovoltaic plant. The most important of inverter losses are the inverter clipping and inverter efficiency losses. Some factors affecting clipping losses and inverter efficiency are the sea surface height, ambient temperature, input power DC, wind speed, air density, radiation, and so on. Due to the high radiation potential, the wide area, and the variety of climate in Kerman province, in this article, Kerman province has been selected for the installation of photovoltaic power plants and the effects of environmental factors on inverter clipping losses and inverter efficiency are studied in different areas of Kerman. In simulating the effects of several factors such as wind speed, radiation, altitude, ambient temperature, wiring losses, inverter power consumption during operation and at the night, shadow and dust losses are considered. In addition, the effect of the inverter DC to AC ratio on the inverter clipping losses, power generation capacity, and on the capacity factor of photovoltaic plant have been investigated.

The increasing use of the photovoltaiv sources and their low efficiency, makes it very important to study on different ways of anhancing their efficiency. In this paper, after designing a photovoltaic farm, the heat transfer equations in solar cells are investigated. Considering the effect of the wind speed on these equations, a solution is provided to decrease the temperature and then increase the efficiency of the photovoltaic panels. Therefore, by means of the meteorological data and three softwares (System advisor model, Matlab and Meteonorm), the 1 MW photovoltaic farm in climate condition of Yazd province is simulated. Then, the effect of wind speed on the efficiency of the photovoltaic farm is investigated. Results shows that with the increase of the wind speed up to 17 m/s, the output power of the farm is considerably increased. For the wind speed upper than 17 m/s, the output power increase is negligible.