Analyze power system as shown in Fig. 3 subject to (a) Line to Line bolted fault (b) Double Line to Ground Bolted Fault occurred at bus 3. Compare values of symmetrical and unsymmetrical fault currents under (a) Line to Line Bolted Fault (b) Double Line to Ground Bolted Fault. Pre-fault voltages can be assumed as 1+ 0j = 1< 0° per unit. Transformers T1 and T2 have 345 Y / 20 A KV Transformation Ratio. (1) 4 Power Plant – II Power Plant – I 3 to Generator Generator Transmission Line 1 Transformer 1 Transformer 2 Fig.3: Single Line Diagram for Faults at Bus 3. Positive, Negative and Zero sequence Z-buses are given as: [jo.19 [j0.1437 jo.1211 j0.0789 j0.0563] jo.1211 jo.1696 j0.1104 jo.0789 j0.08 jo.08 j0.08 jo.58 z(2) jo.0789 j0.1104 j0.1696 j0.1211 Ljo.0563 jo.0789 j0.01211 j0.1437] (0)- Zbus z = Zbus j0.19]

Analyze power system as shown in Fig. 3 subject to (a) Line to Line bolted fault (b) Double Line to Ground Bolted Fault occurred at bus 3. Compare values of symmetrical and unsymmetrical fault currents under (a) Line to Line Bolted Fault (b) Double Line to Ground Bolted Fault. Pre-fault voltages can be assumed as 1+ 0j = 1< 0° per unit. Transformers T1 and T2 have 345 Y / 20 A KV Transformation Ratio. (1) 4 Power Plant – II Power Plant – I 3 to Generator Generator Transmission Line 1 Transformer 1 Transformer 2 Fig.3: Single Line Diagram for Faults at Bus 3. Positive, Negative and Zero sequence Z-buses are given as: [jo.19 [j0.1437 jo.1211 j0.0789 j0.0563] jo.1211 jo.1696 j0.1104 jo.0789 j0.08 jo.08 j0.08 jo.58 z(2) jo.0789 j0.1104 j0.1696 j0.1211 Ljo.0563 jo.0789 j0.01211 j0.1437] (0)- Zbus z = Zbus j0.19]

Power System Analysis and Design (MindTap Course List)

6th Edition

ISBN:9781305632134

Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Publisher:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Chapter9: Unsymmetrical Faults

Section: Chapter Questions

Problem 9.2P

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Consider the one-line diagram of power system shown below; a) Develop equivalent circuit expressing all parameters in per unit values select Sbase= 100MVA b) Apply circuit reduction techniques and then find the net impedance(Zeq) at point of fault F2 c) Calculate fault level and fault current
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The Electricity Company of Ghana (ECG) has set up a system for reporting power supply faults in the Greater Kumasi Area, including high or low voltage and frequent power outages. Customers can contact ECG customer service and report their issue, providing their ECG pole reference number. The faults are recorded and sent to the ECG Fault Office for action. However, there is a delay in resolving the faults, and clients have to make several follow-up calls to check on the status of their complaints. The ECG management team conducted a survey and found out that customers want their faults resolved within three hours, and any delay beyond that is unacceptable. The team is looking for a solution that will offer a seamless experience to customers and minimize time and effort wasted. a) Given the information above, and making reasonable assumptions, model the current (‘AS IS’) and explain business processes at ECG Fault Office. b)What would the future state (ASTOBE) look like?Provide a new…
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