This subject covers the construction, principle of operation, installation and maintenance of various types of Electric Plant. This module is intended to provide students with sufficient understanding of electrical machines and plant to enable them specify suitable plant for particular applications.
This module introduces students to the construction, principle of operation, installation, maintenance and efficiency of various types of electric plant.
Lecture
- AC Motors and generators
- Construction and principle of operation of Power transformers
- Induction motor: Equivalent circuit. Variation of torque with slip. Maximum torque. Speed control, modern methods, Separate windings and pole changing.
- Investigate the construction of the following motors: 1) The universal; 2) The single phase induction; 3) The three phase squirrel cage induction; 4) The three-phase wound rotor induction; and 5) D.C. series and shunt motors and generators.
- Investigate the operation of the DC shunt machine
- Low voltage circuit breakers construction and operation, Thermal and magnetic overloads. Oil and air break C.B.s. Principle of arc extinction.
- Switch gear, metering. Low voltage circuit breaker control, local and remote, electrical and mechanical interlocking. Low voltage circuit breaker ratings: voltage, current, fault MVA coordinate this section with ESD).
- Synchronous and asynchronous machines, induction motors, single-phase motors and dc machines.
- Methods of starting and control. Analysis of characteristics (electronic speed control plant).
Laboratory:
- Transformers – construction and operation. Complete phasor diagram for a transformer on no-load and load conditions. Equivalent circuit, regulation, maximum and all-day efficiency.
- Transformer tests, open and short-circuit tests. Protective devices, buchholz relay. Three-phase transformers. Parallel operation of transformers. Auto-transformers. Instrument transformers.
- Transformers: carry out the following tests
- Open circuit test
- Short-circuit test.
- Types of motor enclosure, index of protection (IP), ventilation methods, duty cycle, installation and maintenance. Co-ordination of overload protection and fuses.
This module will be taught by lectures. Material covered in lectures will be applied to various design packages in the computer design laboratory. The lecturers will increasingly becoming a facilitator placing greater responsibility on the student to learn beyond the information given.
| Module Content & Assessment | |
|---|---|
| Assessment Breakdown | % |
| Formal Examination | 70 |
| Other Assessment(s) | 30 |