Power systems and machines

Examiner: Dr. Hanif Livani, hlivani@unr.edu

Text

Power System Analysis and Design, Glover and Sarma, Third Edition, Brooks/Cole, 2002.

Objectives

1. Solve problems involving phase angles, line-line or line-neutral voltages and line or phase currents for a three-phase power system
2. Obtain single-phase and three-phase real and reactive power and the power factor
3. Solve power factor correction problems
4. Model power system transmission lines
5. Model single phase and three-phase transformers
6. Model synchronous machines

Exam topics

1. Fundamental
   • Phasors
   • Instantaneous power in single-phase AC circuits
   • Complex power
   • Network equations
   • Balanced three-phase circuits
   • Power in balanced three-phase circuits
   • Advantages of balanced three-phase versus single-phase systems
2. Power transformers
   • The ideal transformer
   • Equivalent circuits for practical transformers
   • The per-unit system
   • Three-phase transformer connections and phase shift
   • Per-unit model of three-phase two-winding transformers
   • Three-winding transformers
   • Autotransformers
3. Fundamentals of electrical machines
   • DC, synchronous, and AC machines
4. Transmission lines parameters
   • Transmission-line design considerations
   • Resistance
   • Conductance
   • Inductance (solid cylindrical conductor)
   • Inductance (single-phase two-wire line and three-phase three wire line with equal phase spacing)
   • Inductance (composite conductors, unequal phase spacing, bundled conductors)
   • Series impedances (three-phase line with neutral conductors and earth return)
   • Capacitance (single-phase, two-wire line and three-phase, three-wire line with equal phase spacing)
   • Capacitance (stranded conductors, unequal phase spacing, bundled conductors)
   • Parallel circuit three-phase lines
5. Transmission lines
   • Steady-state operation: Medium and short line approximations
   • Transmission-line differential equations
   • Equivalent π circuit
   • Maximum power flow
   • Line loadability
   • Reactive compensation techniques
6. Power flow analysis
   • The power-flow problem