Introduction to electric machines

What is a permanent magnet?

Any material that has a capacity of producing its own flux

What is an Electrical Machine?

Component that converts electrical to mechanical energy and vice versa

What is an electrical Drive ?

A comprehensive system that converts voltage/ current to useable output at expected by the end user

Why do you need electric drive?

For Fixed speed Operations (E.g u want a blender to spin at same speed), Variable speed operations

What is a VSI?

Voltage Source Inverter

The input voltage in the voltage source converter is constant whereas the input current may be constant or variable

What is a CSI?

Current Source Inverter

The input Current in the current source converter is constant whereas the input voltage may be constant or variable

Which one is used more and why?

The VSI is used 90% of the time due to it being less bulky as it doesnt require a massive inductor to balance out the current.

Moreover, The devices, significantly bigger because it has to dissipate a lot of heat and there are challenges associated with it.

Also, with VSI you can go to the frequencies which are good enough in terms of operation of the machine. e.g 60 and 100kHz

While with CSI you will have big problems when you go higher than 6-13kHz

What are the different types of First Generation machines?

Universal Motor, Single Phase, Three Phase

What are the different types of Second Generation machines?

Brushed PM DC Machine , PM AC Machines

What are the different types of Third Generation machines?

Brushless PM DC Machine

Brushless PM AC Machine

Reluctance Machines

What are the types of Conventional 1st Gen Machines

DC Machine, Induction Machine, Synchronous Machine