VOLTAGE ORIENTED CONTROL – SIMULATION
3.8 Grid modeling
Figure 3.45 : Grid connected converter
The aim of this part is to modify the model introduced in section “2.2.2 Mathematical model” (Figure 2.4) to simulate a grid connected converter. We are going to add the grid voltage and impedance Eg, Rg and Lg. A switch will be modeled with a resistor Rb (high value for an open switch, very small value for a switch closed). We can write four equations as below.
First equation : ig
Second equation : i
Third equation : Vc
Fourth equation :
With these four equations, we can establish the scheme Figure 3.47 to replace the simple grid model of Figure 3.46 (establish in section “2.2.2 Mathematical model” Figure 2.4).
Figure 3.46 : Simple grid model (phase A)