Power systems theory - generation, transmissions and distribution
Many questions sent in to the site are in connection with motor starting and in particular star-delta. For all but the simplest application, there is merit in performing a more detailed study.&... read more..
Traditionally substations have used circuit breakers, current transformers (CT), voltage transformers (VT) and protection relays all wired together using copper cables. With advances in digital... read more..
Modelica is an open source (free) software language for modelling complex systems. Having never used it before, I thought I would download a development platform and see how it stacked up. This... read more..
Within Europe the European Committee for Electrotechnical Standardization (CENELEC) has standardised the both the designation and colour of cables. These are published in CENELEC document... read more..
A UPS is an uninterruptible power supply. It is a device which maintains a continuous supply of electrical power, even in the event of failure of the mains (utility) supply. A UPS is inst... read more..
Power cables can basically be classified into earthed and unearthed cables, where earthed and unearthed refer to the application for which the cable is used. Earthed system refers to a three phase syste... read more..
Photovoltaic (PV) cells (sometimes called solar cells) convert solar energy into electrical energy. Every year more and more PV systems are installed. With this growing application, it's ... read more..
Fire resistant and fire retardant cable sheaths are design to resist combustion and limit the propagation of flames. Low smokes cables have a sheath designed to limit the amount of smoke and toxic ha... read more..
Capacitors have numerous applications in electrical and electronic applications. This note examines the use of capacitors to store electrical energy. The sidebar shows details of a typical c... read more..
If two dissimilar metals are touching and an external conducting path exists, corrosion of one the metals can take place. Moisture or other materials acting as an electrolyte between the metals... read more..
While not as popular as it once was, frame leakage protection does still have some use in some circumstances. In essence frame leakage is an earth fault type protection. A current transfo... read more..
Ever wondered what kind of power an aircraft uses when parked at the airport stand.
Normally the aircraft generates it own power, but when parked with the engines switched off power provided ... read more..
I received this question by email a few weeks. First thoughts was that it is a product of the mathematics of rotating a straight conductor in a magnetic...
The (relatively new) switchgear and control gear standard, IEC 61439 'Low-voltage switchgear and controlgear assemblies' has three methods which can be...
The European Union is implementing a voluntary code of practice for participants with the aim of improving the overall efficiency of data centres. As part...
Control theory looks at how systems work and are controlled from a mathematical view. This note gives a brief introduction to some of the concepts – more...
"I can live with doubt and uncertainty and not knowing. I think it is much more interesting to live not knowing than to have answers that might be wrong...
Induction motors are frequently used in both industrial and domestic applications. Within the induction motor, an electrical current in the rotor is induced...
Here’s list of some famous scientists. Deliberately short, with the aim to provide a quick memory jog or overview. If your looking for more detailed information...
Traditionally generation of electricity has involved rotating machines to produce alternating sinusoidal voltage and current (a.c. systems). With the development...
If you have no idea how electrical circuits work, or what people mean then they talk about volts and amps, hopefully I can shed a bit light. I’m intending...
Two driverless and solar power vans have departed from Italy on their way to China via the silk road. During the 13,000 kM trip the vans will drive themselves...
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