How to connect simscape elements and simulink/simpower system elements in matlab 2010?

Simulink model

Answer 1

[Sebastian Castro]

In R2011b, SimPowerSystems (SPS) includes some interface blocks that do the work for you. However, you should still be able to do it in earlier versions if you copy the block implementation from the documentation page.

Look at the diagrams in both these pages:

http://www.mathworks.com/help/physmod/sps/powersys/ref/currentvoltagesimscapeinterface.html

http://www.mathworks.com/help/physmod/sps/powersys/ref/voltagecurrentsimscapeinterface.html

Notice that you're using a Current Sensor in SPS and feeding it into Simscape with a Current Source. Similarly, you're sensing voltage in Simscape with a Voltage Sensor and feeding it into SPS with a Voltage Source.

The other block does the opposite by switching the locations of the current and voltage. Choosing the right block prevents you from doing something (numerically) unstable like connecting 2 voltage sources in parallel or 2 current sources in series, as this is not "physical".

One other warning: If you do these connections you will get an algebraic loop. The interface blocks above give you many options to automatically break the loop using Unit Delays, low-pass filters, etc. Again, this will be something you have to handle yourself for versions earlier than R2011b.

... or, if you have access to it, you could always upgrade to R2011b or later :)

- Sebastian