Question 4: What happens if the speed of a DC shunt generator is lower than critical speed during no- load operation? A) The generator will produce excessive voltage B) The generator will not produce any voltage C) The generator will produce unstable voltage A)- Indicate whether the following statements are true or false and correct the false statements 1-The efficiency of a transformer at load 0.8 p.f. Lag is more than at load 0.8 p.f. Lead 2- No load current in a transformer lags behind the voltage by about 15° 3- There is no output from the transformer under short-circuit conditions 4-. The full-load copper loss and iron loss of transformer are 800w and 600w respectively, the copper loss and iron loss at half load will be 400w and 300w respectively 5- The imaginary component of no load current for transformer is responsible for the consumption of iron loss

Question 4: What happens if the speed of a DC shunt generator is lower than critical speed during no- load operation? A) The generator will produce excessive voltage B) The generator will not produce any voltage C) The generator will produce unstable voltage A)- Indicate whether the following statements are true or false and correct the false statements 1-The efficiency of a transformer at load 0.8 p.f. Lag is more than at load 0.8 p.f. Lead 2- No load current in a transformer lags behind the voltage by about 15° 3- There is no output from the transformer under short-circuit conditions 4-. The full-load copper loss and iron loss of transformer are 800w and 600w respectively, the copper loss and iron loss at half load will be 400w and 300w respectively 5- The imaginary component of no load current for transformer is responsible for the consumption of iron loss

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 3.16MCQ: In developing per-unit circuits of systems such as the one shown in Figure 3.10. when moving across...

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