Custom mains surge protector

[DJam]

Hi all, I'm an electrical/electronics engineering apprentice in the UK, currently doing my HND. I have to do some kind of electrical/electronics project next month, and my idea is to design a surge protected extension lead circuit, possibly with some digital displays showing power usage.

Some things I am unclear on are:

1) How to wire up live, neutral and ground lines on Multisim like in UK mains wiring.

2) How to use a voltage controlled resistor to emulate a MOS (for surge protection).

3) Is it possible to get a display readout on power usage?

4) Is this project even possible on Multisim, or shall I think of something else.

I'm really struggling for project ideas, and this is all I have come up with, that doesn't seem too complex or too easy.

I appreciate any feedback you may have for me.

Thanks Alot,

Daniel 

[S.Limb]

Hi Daniel

Thank you for your post and your detailed description of what you are aiming to achieve. As I understand you are looking to create a power surge protection circuit using multisim.

Yes your project is possible to implement in Multisim, I have found the components you will need and I have illustrated these in the attached document. There is also a large number of examples available in Multisim under the help tab and in the find examples field, I recommend you look into these, while searching I found a few examples that will benefit your project, under the analysis folder is AC analysis, under the analog folder is power electronics and under advanced is an analog example. There is also a calculator example that you may find helpful for your power calculations as Multisim doesn't do mathematical analysis in a function, you will have to implement the circuitry yourself. So please look into these and use them as a reference tool in the future.

As well as the offline resources, there is a large range of examples and articles on multisim and your project idea, both on the National Instruments and on the web, so don't forget to use these for reference and ideas on how to implement parts of your circuit. I have included some of the links I fell will be most useful to you.

Power surge protection circuit

Using A Phasor Diagram With NI Multisim Simulations

How To Use NI Multisim Measurement Instruments

Creating a Custom Component in NI Multisim

component reference guide

Continuous Data Display on the Scope in Multisim

Multisim fundamentals

If you would like to look through this and then get back to me with any further questions or queries.

Thank you