Maximum DC Current

Most inverters are designed such that the minimum DC voltage and the maximum DC current coincide with the curve of maximum AC output power, thus largely avoiding the possibility of the DC current limit being encountered before the AC output power limit is reached. However, a minority of inverters are not designed in this way, and we evaluate the impact of the maximum DC current limit here.

At each time step, all points in \(IV_{\text{array,PACmax}}(t)\) where I is greater than the inverter maximum DC current are removed, to give \(IV_{\text{array,IDCmax}}(t)\).

The Effect associated with inverter maximum DC current for array at time t is calculated as:

$$\Delta_{inv,IDCmax}\left( t \right) = \left( \frac{MPP(IV_{array,IDCmax}\left( t \right))}{MPP(IV_{array,inv}\left( t \right))} - 1 \right) \bullet 100%$$

Average over time and arrays to evaluate effect for entire PV plant as previously. Where an annually-representative result is to be calculated, it is important to de-season.