Q1.An industrial load can be supplied on the following alternative tariffs. (a) H.V. supply at Rs. 70 per kVA per annum plus 5 p per kWh (b) L.V. supply at Rs 75 per kVA per annum plus 6 p per kWh (c) Transformers and switchgear suitable for the HV supply cost Rs 60 per KVA, the full load transformation losses being 3%. The fixed charges are 20% per annum on the capital cost of the H.V. plant and the installation works at full load. If there are 50 working weeks in a year find the number of working hours p week above which the H.V. supply is cheaper. Assume a load of 2000 kW at unity power factor.

Q1.An industrial load can be supplied on the following alternative tariffs. (a) H.V. supply at Rs. 70 per kVA per annum plus 5 p per kWh (b) L.V. supply at Rs 75 per kVA per annum plus 6 p per kWh (c) Transformers and switchgear suitable for the HV supply cost Rs 60 per KVA, the full load transformation losses being 3%. The fixed charges are 20% per annum on the capital cost of the H.V. plant and the installation works at full load. If there are 50 working weeks in a year find the number of working hours p week above which the H.V. supply is cheaper. Assume a load of 2000 kW at unity power factor.

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

Chapter3: Power Transformers

Section: Chapter Questions

Problem 3.33P: Consider the three single-phase two-winding transformers shown in Figure 3.37. The high-voltage...

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