Distribution System Training

This module, the first in the “Distribution System Training” series, initiates the review of electrical fundamentals that provide the basis for detailed study of equipment and systems in subsequent modules. The objective of this module is to develop an understanding of AC power generation, frequency and characteristics of the sine wave.

The effect of pure resistance in an AC circuit is also discussed, including the relationship between voltage, resistance, power and energy. On completion of this module and associated workbook, the participant should be able to understand the following concepts, and apply them in day-to-day practice.

• Requirements for power balance, i.e. power supply must equal power demand (including losses)
• Current and power flow through a simple DC circuit
• Calculation of equivalent resistance for parallel circuits
• Calculation of line voltage drop and line power loss
• The use of high voltages to reduce transmission and distribution line losses
• The relationship between power and energy
• The principle of AC power generation using a rotating magnetic field
• Development of the voltage sine wave in relation to the rotor angle
• Physical interpretation of the current sine wave, i.e. current flow changes direction every half cycle
• Relationship between frequency, number of poles and speed of rotation
• Synchronous operation of generators connected in parallel
• The effects of pure resistance in an AC circuit
• Calculation of instantaneous values, and the resultant power curve
• The meaning of RMS values