Control for a passive-ventilation system of a building

A method for controlling a passive-ventilation system of a building, comprising:

• determining an outdoor air temperature (Tout) of air in an environment of the building;
• determining an indoor air temperature (Tint) of at least one zone inside the building;
• calculating a temperature difference (ΔT) by subtracting the determined outside air temperature (Tout) from the determined indoor air temperature (Tint);
• under condition that the calculated temperature difference (ΔT) is greater than zero, controlling a state of at least one passive-ventilation device of the passive-ventilation system to be in any of:
• a closed state, an open state, or one of one or more intermediate states between the closed state and the open state, where each of the intermediate states corresponds to one value of an opening fraction value (OF) of the at least one zone inside the building varying between 0 and 1, where 0 corresponds to the closed state and 1 corresponds to the open state, and where the at least one passive-ventilation device is configured for a fluidic coupling of at least one respective zone of the at least one zone inside the building with the environment of the building;
• wherein the state of the at least one passive-ventilation device is controlled via setting the opening fraction value (OF), the opening fraction value (OF) being set to:
• an upper fraction limit equal to 1, under condition where the calculated temperature difference (ΔT) is equal to or below a pre-set lower temperature difference limit (k);
• a lower fraction limit (I) equal to or greater than 0 and less than 1, under condition where the calculated temperature difference (ΔT) is equal to or above a pre-set upper temperature difference limit (m);
• and
• a value of a passive-ventilation function of the calculated temperature difference (ΔT) otherwise, the passive-ventilation function monotonically decreasing with increasing calculated temperature difference (ΔT),
• the state of the at least one passive-ventilation device is only controlled via setting the opening fraction value (OF) if both the determined outdoor air temperature (Tout) and the determined indoor air temperature (Tint) lie in a range between a lower set point and an upper set point, and is set to the closed state otherwise, where the lower set point and the upper set point are settable as dynamic set points according to a formula depending on a comfort temperature, where the comfort temperature is settable according to another formula depending on a running mean outside temperature, and
• the lower set point is a heating set point (TLL,HSP) and the upper set point is a cooling set point (TUL,CSP).

A method for controlling a passive-ventilation system of a building, comprising:

• determining an outdoor air temperature (Tout) of air in an environment of the building;
• determining an indoor air temperature (Tint) of at least one zone inside the building;
• calculating a temperature difference (ΔT) by subtracting the determined outside air temperature (Tout) from the determined indoor air temperature (Tint);
• under condition that the calculated temperature difference (ΔT) is greater than zero, controlling a state of at least one passive-ventilation device of the passive-ventilation system to be in any of:
• a closed state, an open state, or one of one or more intermediate states between the closed state and the open state, where each of the intermediate states corresponds to one value of an opening fraction value (OF) of the at least one zone inside the building varying between 0 and 1, where 0 corresponds to the closed state and 1 corresponds to the open state, and where the at least one passive-ventilation device is configured for a fluidic coupling of at least one respective zone of the at least one zone inside the building with the environment of the building;
• wherein the state of the at least one passive-ventilation device is controlled via setting the opening fraction value (OF), the opening fraction value (OF) being set to:
• an upper fraction limit equal to 1, under condition where the calculated temperature difference (ΔT) is equal to or below a pre-set lower temperature difference limit (k);
• a lower fraction limit (I) equal to or greater than 0 and less than 1, under condition where the calculated temperature difference (ΔT) is equal to or above a pre-set upper temperature difference limit (m);
• and
• a value of a passive-ventilation function of the calculated temperature difference (ΔT) otherwise, the passive-ventilation function monotonically decreasing with increasing calculated temperature difference (ΔT), and
• the passive-ventilation function is a function proportional to {1/sqrt[a1*ΔT]} or proportional to {1/sqrt[a0+a1*ΔT]}, where a0 and a1 are variables, and wherein the passive-ventilation function is limited to a maximum value of 1.