IdealHeatingCoolingPI

Ideal heating and cooling of a zone towards day schedules of set points (trano IdealHeatingCooling): a PI controller per mode, limited by the capacities

FastSmoothBuildings.HVAC.IdealHeatingCoolingPI, model (source)

Purpose

Ideal heating and cooling of a zone towards day schedules of set points (trano's IdealHeatingCooling): one PI controller per mode, its output the share of the capacity of that mode, and the energy of each mode metered.

Equations

With T the temperature of heatPortCon (the zone air) and the set points interpolated in their day tables by dayTable,

• conHea: error T_SetHea(t) − T,   Q_Hea = conHea.y Q_Hea,max;
• conCoo: error T − T_SetCoo(t),   Q_Coo = conCoo.y Q_Coo,max;
• dE_Hea/dt = Q_Hea/3.6·10⁶,   dE_Coo/dt = Q_Coo/3.6·10⁶ (kWh);
• heatPortCon.Q_flow = −(1 − f_rad) (Q_Hea − Q_Coo),   heatPortRad.Q_flow = −f_rad (Q_Hea − Q_Coo).

Both controllers are always enabled, their outputs between 0 and 1 by smooth limits that reach their bounds exactly: a saturated mode gives no heat at all, and the anti-windup keeps its integral from running away while the other mode works. The schedules are interpolated without events.

Parameters

Name	Default	Meaning
TSetHea	[0, 293.15]	heating set point: time of day (s) and set point (K)
TSetCoo	[0, 300.15]	cooling set point: time of day (s) and set point (K)
QHea_flow_max, QCoo_flow_max	106 W	heating and cooling capacities
k	0.1 1/K	gain of both controllers
Ti	300 s	integral time of both controllers
frad	0	radiant share

The controllers keep the other defaults of PI, among them the half-width dY = 10⁻³ of their limits.

Use

Connect heatPortCon to heaPorAir and heatPortRad to heaPorRad of a zone; the meters EHea and ECoo give the demands. See Examples.IdealHeatingRoom.

Parameters

Parameter	Type	Unit	Default	Description
TSetHea	Real		[0, 293.15]	Heating set point: time of day [s] and set point [K]
TSetCoo	Real		[0, 300.15]	Cooling set point: time of day [s] and set point [K]
QHea_flow_max	Real	W	1e6	Heating capacity
QCoo_flow_max	Real	W	1e6	Cooling capacity
k	Real		0.1	Gain [1/K]
Ti	Real	s	300	Integral time
frad	Real		0	Radiant share

Revisions

• October 2026: moved from trano's FastModel.HVAC.