Fault Tree Analysis (FTA) is another technique for reliability and safety analysis. Of primary concern are short circuits, not only because they can cause large damage to the affected system component but also because they may lead to instability of the whole power system. In semiconductor devices, problems in the device package may cause failures due to contamination, mechanical stress of the … This is illustrated in Fig. The power base is selected and is used for all parts of the power system. This type of faulting is common in areas of compression, When the dip angle is shallow, a reverse fault is often described as a thrust fault. "@id": "https://electricalacademia.com/category/electric-power/", "name": "Electric Power" Thus, the various power system components are represented by single-phase equivalent circuits wherein all three-phase connections are assumed to be converted to their equivalent wye connections. The basic idea is that an asymmetrical set of N phasors can be expressed as a linear combination of N symmetrical sets of phasors by means of a complex linear transformation. Equations 12 and 16 indicate that the positive- and negative-sequence networks are to be interconnected in parallel for a line-to-line fault. 2. Nearly all faults will have some component of both dip-slip and strike-slip, so defining a fault as oblique requires both dip and strike components to be measurable and significant 2) Classification of faults on the basis of apparent movement of blocks: Any kind of fault can be modeled and analyzed by symmetrical components, where each fault can be represented by an equivalent circuit. Seismic activity of New Zealand’s alpine fault more complex than suspected, Chrysoberyl : One of the world’s most expensive Gemstone, Deep underground forces explain quakes on San Andreas Fault. c and ground. This article focusses on hard wiring faults that can occur either during normal use, or can be … The fault current in a system can be contributed by any of the following. } ] These include not only failure of some physical component but also errors in the original design of the circuit. Grain Size : What is Grain Size? Basic Concepts. but it is hardly the quickest, or cheapest, way of getting a faulty system… \[\begin{matrix}   \left[ \begin{matrix}   {{I}_{a0}}  \\   {{I}_{a1}}  \\   {{I}_{a2}}  \\\end{matrix} \right]=\frac{1}{3}\left[ \begin{matrix}   1 & 1 & 1  \\   1 & a & {{a}^{2}}  \\   1 & {{a}^{2}} & a  \\\end{matrix} \right]\left[ \begin{matrix}   {{I}_{a}}  \\   {{I}_{b}}  \\   {{I}_{c}}  \\\end{matrix} \right]=\frac{1}{3}\left[ \begin{matrix}   0  \\   \left( a-{{a}^{2}} \right){{I}_{b}}  \\   \left( {{a}^{2}}-a \right){{I}_{c}}  \\\end{matrix} \right] & {} & \left( 11 \right)  \\\end{matrix}\]eval(ez_write_tag([[250,250],'electricalacademia_com-leader-1','ezslot_9',112,'0','0'])); Therefore, it is seen that the negative-sequence component of the current is equal to the negative of its positive-sequence component; that is, $\begin{matrix}   {{I}_{a2}}=-{{I}_{a1}} & {} & \left( 12 \right)  \\\end{matrix}$. Electrical Fa… Converting a set of unbalanced phasors into sets of balanced components greatly simplifies our analysis and is helpful in performing fault calculations, power flow studies, and stability studies.. This could be a broken wire, loose connection, burned out component, etc.Short circui tsoccur when two or more components, which hould be … "@context": "http://schema.org", Faults may be classified into four types. Electrical networks, machines and equipments are often subjected to various types of faults while they are in operation. $\begin{matrix}   {{V}_{c}}={{V}_{a0}}+a{{V}_{a1}}+{{a}^{2}}{{V}_{a2}}=0 & {} & \left( 14 \right)  \\\end{matrix}$eval(ez_write_tag([[250,250],'electricalacademia_com-large-mobile-banner-1','ezslot_12',113,'0','0'])); $\begin{matrix}   {{V}_{b}}-{{V}_{c}}=({{a}^{2}}-a){{V}_{a1}}+(a-{{a}^{2}}){{V}_{a2}} & {} & \left( 15 \right)  \\\end{matrix}$, Because Vb and Vc are equal, Eq. 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