Electrical Machines II

• Dc machines ΙΙ

-Generator operation –series excitation, compound excitation.
− motor operation – series excitation, compound excitation
- motor start.
- speed control.
- motor brake.
• Three-phase transformers
- Construction characteristics, equivalent circuit.
- 3-phase connection types
- open and short circuit tests.
- 3-phase transformers loading.
- Parallel transformers
• Synchronous generators
- Structure. Operation principle and types.
• Turbo-generators:
- Speed control,
- voltage control,
- Equivalent circuit,
-Power control,
- Operation limits
- parallel generators,
• Salient pole generators
- Structure
- Equivalent circuit
Transients
• Asynchronous motors
- Torque-speed characteristics,
- Start,
• Special applications motors (one-phase, universal, others)

On successful completion of this module the learner will be able
to:
1. Understand adequately the ac motors and generators, DCMachines
and Transformers operational principles.
2. Predict the machine operation under different conditions
3. Solve electric machines problems using the applicable
equivalent circuit
4. Adequately install and operate electric machines

Electric Circuits I and II, Electromagnetics, Electric machines I

-

- Evaluation of laboratory exercises (20%)
- Two unannounced tests and one progress test (30%)
- Final exams (50%)

1. Ν. Σκραπαρλής, Β. Μολασιώτης, Δ. Τσιαμήτρος, «Εργαστηρια-
κές Ασκήσεις Ηλεκτρικών Μηχανών Συνεχούς και Εναλλασσο-
μένου Ρεύματος», Εκδόσεις Σύγχρονη Παιδεία.
2. Chapman S., Electrical Machinery Fundamentals, Fourth
Edition, McGraw-Hill Inc.