Resistors
Resistors are electronic components that oppose the flow of current. Manufactured in various types and ranges they have a wide application to electronics...
Batteries
A battery consists of one or more cells, each of which use stored chemical energy to produce electrical energy, There are many types of cells and these...
Variable Frequency Drive
Variable frequency drives are widely used to control the speed of ac motors. This note looks at the mechanisms which enable drive units to control the...
The ac resistance of conductors
In a previous article I looked at the dc resistance of conductors and in this article we turn our attention to ac resistance. If you have not read the...
IEEE Winds of Change
IEEE TV has a part series of videos on wind power and it's implication. For a really good overview to the technologies and issues around wind power, these...
Maximum Demand for Buildings
Estimating maximum demand is a topic frequently discussed. Working out how much power to allow for a building can be very subjective . Allowing too much...
Induction Motor Equivalent Circuit
Induction motors are frequently used in both industrial and domestic applications. Within the induction motor, an electrical current in the rotor is induced...
Network Theory – Introduction and Review
In electrical engineering, Network Theory is the study of how to solve circuit problems. By analyzing circuits, the engineer looks to determine the various...
How a Digital Substation Works
Traditionally substations have used circuit breakers, current transformers (CT), voltage transformers (VT) and protection relays all wired together using...
Three Phase Current - Simple Calculation
The calculation of current in a three phase system has been brought up on our site feedback and is a discussion I seem to get involved in every now and...