الفهرس 
Types of Power Quality ProblemsOnly 14 pages are availabe for public view
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Abstract
As a result of the increasing penetration of energy from renewable sources into the power grid, power quality has currently become a recurring problem. The cause of such problems can be attributed to two main sources, the injected harmonics from renewable energy sources and abnormal operating conditions. Some of the generated power is lost due to harmonic injections of different elements at each stage of a distribution system. Harmonics result from the presence of harmonic producing equipment that causes overheating and malfunctioning of
those devices; these are undesirable as they cause power losses and also affect the voltage profile. The voltage DROP also occurs at distribution feeder due to variations in load demand and many times it falls under the workable operating limits. The unequal loading phases can also make distribution systems less effective. It would be less expensive and time saving if the harmonics and the effects of abnormal operating conditions could be reduced. In order to work efficiently, the distribution system needs to be upgraded. Low pass filters can solve this problem if optimized by using an effective technique. This thesis aims to design optimal single tuned passive filters and find the optimal location of these filters to suppress the harmonic distortion and improve the power quality of networks. The filter design is based on single objective functions and multi-objective functions. This is done under equality constrain and some inequality constraints. This design is calculated using new optimization techniques Jelly Fish optimization technique (JFOT), Arithmetical optimization algorithm (AOA) and a new combined technique depend on the two mentioned techniques. JFOT and AOA techniques are applied to the IEEE 33-bus system, using two scenarios. The first scenario is to apply the two techniques and allocate only one optimal single tuned passive filter at bus 1 in the network. The second one is to apply the two techniques and allocate three optimal single tuned passive filter at
three different buses in the network. The results are compared with results of another manuscript. The results confirm that, JFOT and AOA techniques can be
used to design a single tuned passive filter and determine its optimal parameters also locate its optimal location. A comparison between the two scenarios shows that, the two scenarios are suitable to be applied to the distribution system and first scenario is the suitable solution for minimizing the cost of the filter. For improving the power quality the second scenario is the suitable solution. So, the two techniques are used in a real network of the Egyptian network at Tala city, that contains a PV system, to determine its optimal single tuned passive filter. The advantage of each scenario was used so that only one single tuned passive filter is used to reduce costs, and the optimal allocation of single tuned passive filter is left to the techniques. The results show that the two techniques give suitable parameters and location of the filter within the limits of IEEE 519 standers.
Also, it shows that AOA can improve the power quality of the system than JFOT.
In addition to that, these techniques and the new combined technique are been applied to another network that already contains a single tuned passive filter. The results explain that the existed filter doesn’t achieve all the standard limits and there is still some distortion in the voltage waveform and some problems in power quality. The number of faults and their periods occurred in the network is compared between before allocating the existed filter and after allocating it. from the results of this comparison, it can be noticed that the number of faults and their periods decreased and there is a partial stability to the network. So, a new single tuned passive filters are suggested to be installed instead of the existed one to improve the power quality of the network and achieve all the IEEE 519 standers. The new filter is exposed to make a fully stability to the network.