blockNextChiller

Identify next enable and disable chillers

Information

This block identifies the index of next enabling (yNexEnaChi and yEnaSmaChi) or disabling chiller (yDisSmaChi and yLasDisChi) based on the current chiller stage setpoint uStaSet and the chiller status setpoint uChiSet.

This implementation assumes that the stage-up process (increased uStaSet) will enable only one more chiller (yOnOff=false), or enable a larger chiller and disable a smaller chiller (yOnOff=true); the stage-down process (decreased uStaSet) will disable only one existing chiller (yOnOff=false), or disable a larger chiller and enable a smaller chiller (yOnOff=true).

Note that when applying the sequence:

  • If it is not in the staging process, the outputs yNexEnaChi, yDisSmaChi, yLasDisChi, yEnaSmaChi equal 1. The yOnOff is false.
  • If it is in the staging up process (yUp=true), the outputs yLasDisChi and yEnaSmaChi, which become valid only when it is in the staging down process, equal the default 1.
  • If it is in the staging down process (yDow=true), the outputs yNexEnaChi and yDisSmaChi, which become valid only when it is in the staging up process, equal the default 1.

Parameters

TypeNameDefaultDescription
IntegernChi2Total number of chillers

Connectors

TypeNameDefaultDescription
Buildings.Controls.OBC.CDL.Interfaces.IntegerInputuStaSetChiller stage setpoint
Buildings.Controls.OBC.CDL.Interfaces.BooleanInput[nChi]uChiSetVector of chillers status setpoint
Buildings.Controls.OBC.CDL.Interfaces.BooleanInputendProTrue: the staging process is end
Buildings.Controls.OBC.CDL.Interfaces.BooleanOutputyUpTrue if it is in staging up process
Buildings.Controls.OBC.CDL.Interfaces.BooleanOutputyDowTrue if it is in staging down process
Buildings.Controls.OBC.CDL.Interfaces.IntegerOutputyNexEnaChiNext enabling chiller index
Buildings.Controls.OBC.CDL.Interfaces.IntegerOutputyDisSmaChiSmaller chiller to be disabled in staging-up process
Buildings.Controls.OBC.CDL.Interfaces.BooleanOutputyOnOffTrue: if the stage change require one chiller to be enabled while another is disabled
Buildings.Controls.OBC.CDL.Interfaces.IntegerOutputyLasDisChiDisable last chiller when it is in stage-down process
Buildings.Controls.OBC.CDL.Interfaces.IntegerOutputyEnaSmaChiSmaller chiller to be enabled in stage-down process

Revisions

  • May 06, 2020, by Jianjun Hu:
    First implementation.