اسلامی مملکت کے بین الاقوامی تعلقات عصرحاضر کے تناظر میں

Islam where considers the superiority of law, provision of justice and equity, building and purification of civilization and emphasis on the welfare of society, there ensures the first priority to humanity, peace and prosperity in the external relations. Islamic state keeps relations on the basis of equality with the world and non-Muslim citizens living within the state. On this belief and ideology Islam invites the world to set together. Islam on these principles of Islamic ideology and belief sets the foundation of collectiveness. On this principle the whole philosophy of life and living system are embraced, and the same Islamic law is the foundation of nations, on this behalf the Islamic state organized the relation with other states. In this way Islamic state on these principles keep relations with other states and within the state relations between Muslim and non-Muslim citizens on the basis of brotherhoods, equality, mercy and the principles of dignity of human being. Along with peace Islam set the principles of war which comprise ethical and prison limitations, duties and ethics amongst warrior, difference between the rights of fighters and non-fighters, treatment with pact holders and prisoners, and specified the way of better treatment with the defeated nations. He thought the manners of war to bloody man who consider everything right during the war. Islam lays great stress on equality, social justice, brotherhood and peace not only in state but across the boarders too. In this article a deep study is done to explain the relations of an Islamic state with other states. Islamic foreign policy emphasizes on the principles of equality among all the human beings and all the races and nations. Islam builds international relation on humanitarian basis.

State Estimaton Technique for Impedance Matching in Distribution Feeder Reconfiguration

State estimation has been adopted by the power system researchers in the late 1960’s. Later on, state estimation was applied to the transmission system. Recently state estimation has become cornerstone among the modern control centers tools for the automation of distribution system. In this research work, state estimation has been implemented for automatic feeder reconfiguration. Automatic feeder reconfiguration can be accomplished by matching the impedances of two different feeders. Once the impedances are matched, static transfer switch perform the feeder reconfiguration effectively and efficiently. The liability of power distribution companies is to provide reliable and good quality power to the customers. Due to the technological advancement and the large scale production, usage of the sensitive equipment has been increased. The sensitive equipment requires quality power through reliable power delivery system. Power delivery system includes feeders and laterals to transfer power from the substation to the consumer end. As the feeders and the laterals are radially operated, therefore the chances of power interruption always exist. Power interruption may occur either due to faults or due to the maintenance or replacement of any components of the distribution system e.g. a distribution transformer. Voltage sag is another cause of interruption of sensitive equipment. To overcome this problem, sensitive equipment should be fed through two independent feeders. If the preferred feeder fails, the sensitive load should be transferred to the alternate feeder. A fast and efficient transfer switch can complete this transfer. Static transfer switch (STS) system has been developed to transfer the load from the preferred feeder to the alternate feeder when voltage sag or fault occurs on the preferred feeder. The most important parameter of the STS-system is the speed of operation or the transfer time so that the load should not be interrupted. To reduce the transfer time and hence to expedite the transfer process, it is necessary that both feeders have the same voltage angle at the point-of-installation (PoI) of the STS. If the impedances of both the feeders are identical then voltage phase difference will be zero. To match the impedance, state estimator has been designed to estimate the voltage angle of both the feeders. To mitigate the voltage phase difference, shunt capacitor has been installed and consequently the transfer time of the STS has been reduced. However, the control logic strategy of the STS-system also affect the transfer time. Two different control logic techniques namely delay logic and forced commutation technique, have been developed and simulated using PSCAD/EMTDC software. If the delay logic technique is utilized then the voltage phase angle of both feeders must be identical. The developed state estimation technique can be implemented to match the impedances and hence the voltage angle to reduce the STS transfer time. However, forced commutation technique can accommodate the phase difference by commutating the outgoing thyristor forcefully. But forced commutation technique require more components e.g. capacitor, inductor, auxiliary thyristors etc. Both techniques are implemented to solve the problems related to the feeder overloading. The problem of overloading has been solved through feeder reconfiguration. STS-system installed at critical location, transfer the sensitive load to the lightly loaded alternate feeder. This phenomenon can be termed as feeder reconfiguration using load-balancing. The development of the STS-system has solved the problem of load interruption. The reliability of the power distribution system has been improved and the sensitive load now operates without power interruption.