Simscape DC-DC converter Efficiency.

I have a question that I don't see the answer to anywhere on the internet.

Here it is: For my final Bach THesis I am trying to compare a DC and AC microgrid in terms of efficiency as one of my research topics. In Simscape there are blocks with a converter which only require that you set the efficiency based on output current.. For some reason I am unable to get this right. The way I see it. when I put a variable resistor on the output and change its resistance, I should get as a current measurement the current minus the efficiency percentage I have put. But I don't get that. I input [0,10,20,30,40,50,60,70,80,90,100] as an efficiency vector for [0,10,20,30,40,50,60,70,80,90,100] as output currents. SO I expect that for 100volts output and a 2 ohm resistance that I get 50% efficiency which should give 1/2 of 50 which is 25 instead i am getting the default value. How does this component work?I did read the help for it, but I do not see what I do not understand. Can someone give me some tips on how i can fix this and maybe how I can approach this task? Thanks in advance.

Answer 1

[Sabin]

The way a power converter works is to converter power from one end to another. In this case, it is a DC-DC converter that is used to convert power from 1 terminals to 2 terminals (this blocks is not bidirectional). If the reference voltage is 100 V and load resistance is 2 Ohm, we expect 50 A output current. In case of 100% efficiency we have that v1*i1=v2*i2. If efficieny is less than 100% then we have v1*i1/efficieny=v2*i2. So we will see more input power. In this case for a 50% efficiency we and output power 5 kW means that we have 10 kW input power. I hope this helps.