{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

DRIVES ASSIGNMENT SOLN

# DRIVES ASSIGNMENT SOLN - Cast I ron Cast Steel UNIVERSITY...

This preview shows pages 1–5. Sign up to view the full content.

Cast Iron Cast Steel Figure 1- magnetic circuit V UNIVERSITY OF TECHNOLOGY, JAMAICA FACULTY OF ENGINEERING ELECTRIC DRIVES AND MACHINES 1 ASSIGNMENT #1 LECTURER : L. Daley DATE SUBMITTED: March 10 th 2010 Group Members: Tineicesa Bradnock - 0702079 Andre` Lindsay - 0702598 Stephan Elliott - 0310609 Roje` Virgo - 0703823

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Question 1(a) The total reluctance of the circuit is total reluctance of the cast iron plus the total reluctance of the cast steel. S T = S cast steel + S cast iron Cast steel section length = 0.7m C.S.A = 0.0025m 2 μ o = 4π x 10 -7 B = 0.75T From the B-H curve on page 24 of Unit 2 for cast steel, at 0.75T, H is 650A/m. B = μ o μ r H μ r = B/(μ o H) = 0.75T/(4π x10 -7 x 650 A/m) = 918.2016 Therefore S cast steel = l/( μ o μ r a ) = 0.7/(4π x 10 -7 x 918.20 x 0.0025) S cast steel = 242,666.6653 A/wb Cast iron section length = 0.2m C.S.A = 0.00625m 2 μ o = 4π x 10 -7 Flux density (B) = 0.3T From the B-H curve on page 24 of Unit 2 for cast iron, at 0.3T, H is 1200A/m.
B = μ r μ 0 H So μ r = B/(μ o H) = 0.3T/(4π x10 -7 x 1200) = 198.9437 S cast iron = l/( μ o μ r a) = 0.2/(4π x 10 -7 x 198.9437x 0.00625) S cast iron = 127,999.986 A/wb Therefore, S T = S cast steel + S cast iron S T = 242,666.6653 + 127,999.986 = 370,666.6513 A/wb The flux will be the same throughout the entire circuit Ø = B x a for any material. Ø = B cast iron x a cast iron = 0.3 T x 0.00625m 2 = 1.875mWb Total mmf in circuit mmf T = Ø x S T = 1.875mWb x 370,666.6513 A/wb = 694.9999712 A = 695A The total MMF in the circuit is also given as MMF = IN where N = 300 turns So I = MMF/N 695.00/300 = 2.317A The current in the coil is 2.317A Question 1(b) i.

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
V (d.c.) I (A) MMF total (A) Flux (Wb) MMF iron (A) MMF steel (A) B iron (T) B steel (T) 70 1.0499 314.9843 0.0008498 108.7715 206.2127 0.135964 0.339911 90 1.3499 404.9798 0.0010926 139.8491 265.1306 0.174811 0.437029 110 1.6499 494.9753 0.0013354 170.9267 324.0486 0.213658 0.534146 130 1.9499 584.9708 0.0015782 202.0043 382.9665 0.252505 0.631263 150 2.2499 674.9663 0.0018210 233.0819 441.8844 0.291352 0.728381 170 2.5499 764.9618 0.0020637 264.1594 500.8023 0.330199 0.825498 Table 1 Question 1b(ii)
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### Page1 / 8

DRIVES ASSIGNMENT SOLN - Cast I ron Cast Steel UNIVERSITY...

This preview shows document pages 1 - 5. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online