Exam 1_04_Sp-11_Solution

Exam 1_04_Sp-11_Solution - ELECTRICAL ENGINEERING...

Info icon This preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
ELECTRICAL ENGINEERING DEPARTMENT EE 255-04 MIDTERM May 2nd, 2011 I have neither given nor received unauthorized assistance during this test. Name (Print)_______________________________ Signature:__________________________ P roblem #1 (10 P oints ) A 132-KVA, 11,000:2,200-V, 60-Hz single-phase transformer has the following circuit parameters: Primary (HVS) Secondary (LVS) R1 = 6.1 R2 = 0. 3 X1 = 31.2 X2 = 1.2 Rc = 57,300 Xm=124,000 Rc and Xm are HVS parameters. The transformer is supplying at 2,200-V the rated load at 0.95 power factor lagging. Use the approximate circuit to determine: 1. The voltage regulation of the transformer, 2. The all-day efficiency of the transformer for the following load cycle: 12 hours full-load and 0.95 power factor lagging 4 hours 50% full-load and 0.95 power factor lagging. 1 I - + 1 V 10 - + ' 2 V 50 j m jX ' 2 I m I = + = = + = 2 61 5 2 1 2 31 6 13 2200 11000 3 0 1 6 2 2 . ) ( * . . . . . eq eq X R V V ° = 0 11000 2 ' A I ° - = ° - = 2 18 12 2 18 11000 132000 2 . . ' V j jX R I V V eq eq ° = + ° - + ° = + + = 25 3 11403 2 61 6 13 2 18 12 0 11000 2 2 1 . ) . . ( .
Image of page 1

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

View Full Document Right Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern