Exponential and Polynomial/ZIP Single phase load in simulink

Dear All,

I am trying to implement a non liner voltage dependent load model. The load models are exponential and as well as polynomial.

For Instance:

Power = P0 (V/Vo)^np

I have trying to implement this as below:

I want to acheive a non linear (distorted sinewave) current draw as shown below to conduct load flow and harmonic studies.

[Joel Van Sickel]

Harron,

what is your question?

Regards,

Joel

[Haroon Zafar]

Actually I am trying to model non linear load in Simulink. The load has exponential form to represent power dependency on input voltage.

Power = P0 (V/Vo)^np

I tried to implement this model as shown above using a controlled current source that is dependent on calculated power and input voltage ( I=P/V). I was expected a distorted sinusoidal output current to represent load behaviour. But instead I am getting something like this which is not a sinusoidal output.

Can you see any error in my simulink implementation?

Answer 1

[Joel Van Sickel]

your absolute value will prevent it from every being truly sinusoidal. The model is outputting exactly the math that you have implemented in Simulink. You need to find a different mathematical representation of your current waveform that does not require a divide by voltage since this is a single phase AC system and voltage will always cross 0.

I think the issue is that you are using a distortion model intended for three phase networks and doing them for a single phase network. If you did this with three phase values you should not have to divide by zero as V is not the instantaneous voltage of any phase, but the overal voltage magnitude of the system.