This ticket is to track several updates to DHC.Plants.Combined.AllElectricCWStorage
Controller issue
See #4194 and the proposed solution at #4194 (comment)
Legacy SOO issue
In heat rejection mode, the chiller condenser valves are modulated to keep the chiller CW flow at design value.
It may well happen that the resulting total CWC flow remains above the CWE flow (so no flow reversal across the CT HX and the plant remains in heat rejection mode), but with
∆T_CWE > ∆T_CWC * m_CWC / m_CWE
resulting in a net cooling effect of the CCW loop (leaving aside the potential additional cooling effect of the CT HX).
The sequence should be fixed to rather rely on the comparison of the enthalpy flow rates between the two loops.
Nota: The SOO has been updated by the designers, and now uses a condition based on ∆T comparison – but as argued above, it's hard to understand how this fixes the problem.
HRC performance curves
There's something fishy with the HRC performance curves used in the model e.g. datChi.EIRFunT at low CW temperatures.
This ticket is to track several updates to
DHC.Plants.Combined.AllElectricCWStorageController issue
See #4194 and the proposed solution at #4194 (comment)
Legacy SOO issue
In heat rejection mode, the chiller condenser valves are modulated to keep the chiller CW flow at design value.
It may well happen that the resulting total CWC flow remains above the CWE flow (so no flow reversal across the CT HX and the plant remains in heat rejection mode), but with
∆T_CWE > ∆T_CWC * m_CWC / m_CWE
resulting in a net cooling effect of the CCW loop (leaving aside the potential additional cooling effect of the CT HX).
The sequence should be fixed to rather rely on the comparison of the enthalpy flow rates between the two loops.
Nota: The SOO has been updated by the designers, and now uses a condition based on ∆T comparison – but as argued above, it's hard to understand how this fixes the problem.
HRC performance curves
There's something fishy with the HRC performance curves used in the model e.g.
datChi.EIRFunTat low CW temperatures.