(a) A 1250 kVA , three phase, $50 \mathrm{~Hz}, 3300 \mathrm{~V}, 300 \mathrm{rpm}$ synchronous generator with a concentric winding has the following design data: $\mathrm{B}_{\mathrm{av}}=0.58 \mathrm{~Wh} / \mathrm{m}^{2}$. $\mathrm{ac}=33000 \mathrm{Am}$, air gap length $=5.5 \mathrm{~mm}$, fields turns per pole $=60$, SCR $=1.2$, peripheral speed $30 \mathrm{~m} / \mathrm{s}$. The effective gap area is 0.6 times the actual area. Find suitor core length. stator bore, turns per phase, mmf for air gap, armature mmf per pole and field current at no load.
Explanation
To determine the suitable core length, we use the formula $l = rac{B imes A imes N}{mmf}$. The stator bore is then calculated using the formula $D = \sqrt{ rac{4 imes A imes N}{\pi imes mmf}}$. The turns per phase is then calculated using the formula $N = rac{mmf}{A imes R}$. The mmf for air gap is then calculated using the formula $mmf = B imes A imes N$. The armature mmf per pole is then calculated using the formula $mmf = mmf imes 4$. The field current at no load is then calculated using the formula $I_f = rac{mmf}{N imes A_m}$.
⬆ Related Topic
📘 Syllabus
View KERALA UNIVERSITY Class 8 Syllabus →
📝 Practice Questions
Practice Previous Year Questions →
🤖 Practice with AI
Generate Practice Question Paper →
📚 Related Concepts
- (a) List down any four key characteristics of Light Rail Transit System (LRT).
- (a) Explain the factors involved in the selection of good alignment for a railway line. Illustrate with necessary sketch
- (a) Explain the functions of rails and various types of rails in use.
- (a) What is negative super elevation? A $1^{\circ}$ curve track diverges from a main curve of $3^{\circ}$ in the opposit
- (a) Why is widening of gauge required on sharp curves? Determine the extent of gauge widening required for a broad gauge