Techno-Economic Analysis of Stand-Alone Hybrid Energy System for the Electrification of Iran Drilling Oil Rigs

This paper explores the potential of use of stand-alone hybrid wind/solar energy system in electrification of calibrating equipment of drilling oil rig in Iran. To achieve this, different hybrid energy system configurations based on calibration equipment demand are proposed. This study puts emphasis on the energy production and cost of energy from both wind turbine and photovoltaic (PV) in the hybrid system. In addition, to make conditions more realistic, the real meteorological data is used for HOMER software to perform the technical and economic analysis of the hybrid system. Results indicate that the PV array shares more electricity production than the wind turbine generator if both wind turbine and PV array are utilized in the wind/solar hybrid system. Moreover, results show that the operational cost will be reduced by the suggested hybrid system

Mitigation of ferroresonance in power transmission system using static synchronous series compensator (SSSC)

Nowadays power quality becomes critical issue in power electrical system. The connection of three-phase transformer through underground cables is growing fast in residential, commercial, industrial and rural applications. Due to this increasing situation, the possibilities of having a series connected capacitance and a non-linear inductance, prone to ferroresonance, become more probable. Not only the cable capacitance (and consequently its length) is an important factor to take into consideration in the transformers ferroresonance, but also other elements are completely necessary for ferroresonance to appear. All these factors affect the ferroresonance appearance in several ways, producing the phenomenon just as well as making some damaging consequences appear. Because of that, it is necessary to have a general idea about what would be the best preventive decisions to take in order to avoid unexpected surprises. First of all it is necessary to have accurate model consist of ferroresonance then we should apply any device to smooth the sharp effect of it. In this project one of the FACTS devise has been applied, static synchronous series compensator (SSSC) to palliate ferroresonance. It is shown that the performance of system becomes better than before and maintain at its acceptable rated value

The effect of magnitude and shape of applied voltage on the partial discharge behavior in cylindrical cavity within a dielectric material

One of the important phenomena which is important in equipment when they are under high voltage stress is Partial discharge (PD). Partial discharge measurement is commonly used to evaluate the performance of the insulation in high voltage system. Modeling of the discharge in insulation can give a better understanding of this important phenomenon. A cavity within a dielectric material is a highly stressed area and the ideal place for starting partial discharge and breakdown. The applied voltage is one of the important factors that PD activity is influenced by that. Previous studies have considered the behavior of PD activity in a spherical cavity at 50Hz of sinusoidal applied voltage. However, still not so much work on the simulation of the PD activity in the cavity under different condition. Also, there is little data are available on the effect of parameters on the PD activity. This paper describes the behavior of PD activity as a function of applied voltage in a cylindrical cavity within a homogeneous dielectric. COMSOL and MATLAB software were used to carry out the simulation based on the finite element method (FEM). The number of PDs per cycle changed with different applied voltage so the highest number of PD at 20kV and the lowest value at 8kV. The maximum PD magnitude is raised from 1200pC at 8kV to 2400pC at 20kV applied voltage. The number of PD is most prevalent for sinusoidal followed by triangular waveform and then sawtooth. Comparison of the simulation results and experimental results are in good agreement. The result can help the researcher to understand more about the characteristics and behavior of partial discharge. Which may help the insulation diagnostic testing or condition monitoring

Surge arrester leakage current analysis by using particle swarm optimization technique

Surge arresters, as protective equipment, are used to limit any overvoltage in a power system resulting from various sources. The surge arrester affects from degradation due to the continuous operating voltage system as well as due to repeated lightning current discharge. Therefore, condition monitoring and health diagnostics of surge arresters are a necessary issue. Hence, as a feasible solution, a condition monitoring based on leakage current measurement techniques was selected to tackle the problem of age diagnostics of surge arresters. The Particle Swarm Search Algorithm was introduced as a method for extracting the third harmonic resistive component, Ir3rd, from the total leakage current. To employ this method for extracting Ir3rd, codes were developed in Matlab. The setting of Particle Swarm Search Algorithm was configured for extracting Ir3rd and accuracy of 94% was obtained