I have been investigating times at which the SPD final dispatch appears to be constrained by the limit on the sum of the HVDC and the shared reserve received at the North Island.
I think the relevant constraint in the SPD Formulation (11.3) is 22.214.171.124, In this formula the RHS is HVDCMaxLessMR.
There appear to have been a few of these events on 17th Dec 2019, specifically TP 19.
On TP 19 the shared reserve north (RESSENTTO6S; RESSENTTO60S) has been constrained to 0. The HVDC dispatch north (DCN) is 826 MW, and there is a price differential across the HVDC. I am trying to find where the limit of 826 came from, but I am not having much luck yet.
Any help would be appreciated, thanks