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Protection system is an integral part of any transmission systems. Previously, numerous protection methods has been suggested for AIR CONDITIONER systems and has been hammered for years to have a better performance. Within the last few decades, HVDC transmission continues to be introduced as being a solution intended for long length transmissions and offshore transmitting, thanks to power electronics technology developments. A fast and flexible control, large capability of tranny, economic reason for ranges over 500km (depends in power electronic devices technology) and less occupied Right of Method (RoW) assessing to HEATING AND COOLING transmission to get a certain electricity capacity[1], are some advantages of utilizing HVDC transmission. A statistical analysis on a HVDC transmission system in china and tiawan shows that thirty eight. 8% of 114 device group black outs were brought on by line safety zone errors[2]. Thus a reliable safeguard method can easily prevent incorrect fault diagnosis and decreases complete power outage as a result. Differential box protection is usually one of classic solutions which has been employed to AC tranny. in [3] a SIEMENS typical HVDC line safety configuration has been studied containing introduced gear protection being a backup protection. An improved differential protection of Current Source Converter (CSC)-HVDC transmission lines has been proposed in [4] which a compound of your blocking product and a newly identified differential current criteria have been used for fault detection. [5] Has identified a signal distance between changer side and inverter part currents which will external and internal wrong doing can be distinguished.
The effect of capacitive current plus the problem interaction channel requirements has been mitigated in [6], [7]. Transient power and other combinations of two edges voltage and current measurements has been analyzed in [8]”[10]. The existence of smoothing reactor and POWER side filters at the two ends of the CSC-HVDC link, allows a few selective non-unit protection strategies[11] to be applied such as Making use of the impedance attribute of smoothing reactors and DC part filters within a faulty circumstances which has been carried out in [2], [12], [13]. Exploring Wave Protection (TWP), which is often used as primary protection [14], can benefit from some strategies such as Theory Component Examination (PCA), Wavelet Transformation (WT) and etc [15]”[17], however the attenuation and distortion of traveling trend which is caused by fault level of resistance and fault location, should be considered. Although some protections has been advised for VSC-HVDC systems, they can be applied to CSC-HVDC transmission lines too. (methods based on current and ac electricity derives may be mentioned as well, which in circumstance, references in introduction component reaches previously mentioned 23). It should be noted that nearly all mentioned researches have applied the concept of threshold as a criteria which is generally obtained no analytical(based on worst case). Usually there exists a trade-off between security and dependability in protection devices which causes inaccuracy in threshold based strategies. at 03 21st, 2005, primary safeguard of Tian-Gaung HVDC system could not find a high impedance fault since amplitude of did not reach its threshold value [18] and the back up protection declined to act as a result of current variances. To conquer the stated problem, we present a composed machine learning criteria based on one particular side measurements, which omits the use of threshold in safeguard. The advised solution is made up of two distinct machine hovering methods, a binary Support Vector Equipment (SVM) like a starting product and a K-Nearest Neighborhood (KNN) classifier for fault classification. In section ¡ the basis of employed divisers is launched. Section ¢ includes the characteristics of errors on a bipolar CSC HVDC test style, and selected features of the device as the classifier advices are also analyzed in this section. In section £, the proposed formula is placed on the test version, simulation can be carried out and results and verification checks are presented. Finally section ¤ can be dedicated to the conclusion.
