1. A 3-phase, 30 MVA, 33 kV alternator has internal reactance of 4% and negligible resistance. Find theexternal reactance per phase to be connected in series with the alternator so that steady current on short-circuit does not exceed 10 times the full load current.[2-178 Q]2. A 3-phase transmission line operating at 33 kV and having a resistance of 5 2 and reactance of 20 Q isconnected to the generating station through 15,000 kVA step-up transformer. Connected to the bus-barare two alternators, one of 10,000 kVA with 10% reactance and another of 5000 kVA with 7:5% reac-tance. Calculate the short-circuit kVA fed to the symmetrical fault between phases if it occurs(1) at the load end of transmission line(ii) at the high voltage teminals of the transformer[(1) 44,500 kVA (ii) 100,000 kVA]3. The plant capacity of a 3-phase generating station consists of two 8 MVA generators of reactance 14-5%each and one 4 MVA generator of reactance 9-5%. These are connected to a common bus-bar fromwhich loads are taken through a number of 3 MVA step-up transformers each having 4% reactance.Determine the MVA rating of the circuit breakers on (1) L.V. side and (ií) H.V. side. Reactances given[1) 15-24 MVA (i) 50-25 MVA]are based on the MVA of each equipment.4. The 33 kV bus-bar of a station are in two sections A and B separated by a reactor. Section A is fed fromfour 10 MVA generators each having 20% reactance and section B is fed from the grid through 50 MVAtransformer of 10% reactance. The circuit breakers have rupturing capacity of 500 MVA. Find thereactance of the reactor to prevent the circuit breakers being overloaded if a symmetrical short-circuit[145 Q]occurs on an outgoing feeder connected to it.5. A generating station has five section bus-bar connected with a tie-bar through 7-5% reactors rated at3000 kVA. Each generator is of 3000 kVA with 10% reactance and is connected to one section of thebus-bar. Find the total steady input to a dead short-circuit between the lines on one of the sections of the[(1) 55-3 MVA (ii 150 MVA]bus-bars (1) with and (iî) without reactors.

As per Bartleby guidelines we are allowed to solve only one question,please ask the rest again.

1. A 3-phase, 30 MVA, 33 kV alternator has intemal reactance of 4% and negligible resistance. Find the external reactance per phase to be connected in series with the altemator so that steady current on short- circuit does not exceed 10 times the full load current. [2-178 Q] 2. A3-phase transmission line operating at 33 kV and having a resistance of 5 Q and reactance of 20 N is

1. A 3-phase, 30 MVA, 33 kV alternator has intemal reactance of 4% and negligible resistance. Find the external reactance per phase to be connected in series with the altemator so that steady current on short- circuit does not exceed 10 times the full load current. [2-178 Q] 2. A3-phase transmission line operating at 33 kV and having a resistance of 5 Q and reactance of 20 N is

Introductory Circuit Analysis (13th Edition)

13th Edition

ISBN:9780133923605

Author:Robert L. Boylestad

Publisher:Robert L. Boylestad

Chapter1: Introduction

Section: Chapter Questions

Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...

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