EP4596991A1

EP4596991A1 - Method and system for managing heating, ventilation, and air conditioning systems

Info

Publication number: EP4596991A1
Application number: EP25155021.6A
Authority: EP
Inventors: Marco Scaramelli; Gaetano Lapenta
Original assignee: Fybra Srl
Current assignee: Fybra Srl
Priority date: 2024-01-31
Filing date: 2025-01-30
Publication date: 2025-08-06

Abstract

A method for managing an air conditioning system (100) of an environment, wherein the environment is provided with ventilation means (101) of the natural and/or forced type, comprises the steps of detecting an inner temperature (T) of an environment before activating the ventilation means (101); defining a significant temperature variation (ΔT_s) that the system (100) can obtain when the ventilation means (101) are activated and a significant variation time (t_vs) as the time taken by the system (100) to achieve the significant temperature variation (ΔT_s); setting an activation time (tv_on) of the ventilation means (101); setting a deactivation time (tv_off) of the ventilation means (101); calculating a switch-off time of the system (t_boost) as a function of at least the deactivation time (tv_off) of the ventilation means (101), the inner temperature (T), the minimum temperature (T_min) and a temperature variation rate when the ventilation means (101) are deactivated (vT_close).

Description

The present invention relates to a method and system for managing an air-conditioning system of an environment. In particular, the method and system according to the present invention are adapted to control an air-conditioning system of flats, offices, business premises and still more. In the context of this description, "air-conditioning system" means a system capable of performing heating, cooling or both functions.
Several types of methods for managing air-conditioning systems are known in the state of the art. Typically, these methods vary depending on the type of system, and make it possible to optimise a target value such as, for example, the temperature value in the environment to be air-conditioned, or the energy consumption of the system.
Methods for monitoring the air quality of an environment are also known, purely by way of example the one described in the Italian patent application IT 102021000029369 and the corresponding European patent application EP 4184071 A1 , both on behalf of the same Applicant.

SUMMARY OF THE INVENTION

Disadvantageously, the methods for managing air-conditioning systems of the known type disregard air quality control. This parameter is either not taken into account in managing the system, or is considered as part of an environment ventilation system integrated in the system itself, e.g. a forced ventilation system. Consequently, either the environment and associated system are already suitable for this type of system, or these methods are inapplicable.
In addition, the methods for managing systems of the known type are not designed to take into account the operation of ventilation systems, unless they are integrated into the ventilation system itself. Known methods therefore merely react to the temperature variation in the environment rather than anticipate it.
At the same time, the known-type air quality control methods, whilst being very versatile as they can also be used with natural ventilation, fail to guarantee adequate thermal comfort during the environment ventilation step.
In this context, the technical task underlying the present invention is to propose a method and a system for managing an air-conditioning system of an environment that overcome the drawbacks of the above-mentioned prior art.
In particular, the object of the present invention is to make available a method and system for managing an air-conditioning system for an environment that can be applied to any type of environment, even those without forced ventilation.
The defined technical task and the specified objects are substantially achieved by a method and system for managing an air-conditioning system of an environment comprising the technical characteristics set forth in one or more of the appended claims.

LIST OF FIGURES

Further features and advantages of the present invention will become clearer from the indicative, and therefore non-limiting, description of a preferred but non-exclusive embodiment of a method and system for managing an air-conditioning system in an environment, with reference to the accompanying drawings wherein:

Figure 1 is a block diagram showing the operation of a system for managing an air-conditioning system of an environment in accordance with an embodiment of the present invention.

DETAILED DESCRIPTION

With reference to the enclosed figures, 1 indicates a control system which can be associated with an air-conditioning system 100 of an inner environment. The environment is provided with ventilation means 101, which may be of the natural and/or forced type. In particular, forced-type ventilation means may comprise either a ventilation system that is separate or integrated into the system 100 such as a fan (not shown) placed inside a duct connected in fluid communication to the environment via a vent (also not shown). The ventilation means 101 can also be of the natural type, such as windows, doors, French windows, basement windows, vasistas or still more. More generally, natural ventilation means are understood as one or more openings capable of allowing or preventing the inlet of air from outside. In general, while in forced ventilation systems the air exchange rate is imposed by the means used, in natural ventilation it is variable, and depends on the temperature difference between the inner environment and outer environment. It should be noted that the control system 1 can take into account both natural and forced ventilation, even when both of them are present.
The characteristics of the ventilation means 101 are considered to be known at the time of the specific implementation of the control system 1. In particular, the ventilation means 101 are capable of supplying air at an inlet temperature T_ext which, for natural ventilation means, corresponds to the outside temperature. It is therefore possible to define a minimum temperature T_min when the ventilation means 101 are activated and the system 100 is deactivated. This value can be calculated in various ways, including, for example, the one described in European patent application publication EP 4184071 A1 .
Regarding the system 100, which is not part of the present invention, it may comprise any combination of means suitable for air-conditioning an inner environment. In particular, it may comprise any combination of radiant elements, heat pumps, fan coils or other. It should be noted that the system 100 may be capable of heating the environment, cooling it, or it may be set up to operate in both modes.
The system 1 further comprises a temperature sensor 2, which is adapted to be placed in the environment to be air-conditioned. The temperature sensor 2 is configured to detect the inner temperature T of the environment before the activation of the ventilation means 101.
The system 1 further comprises acquisition means 3, which are adapted to detect an air inlet temperature value T_ext. In the case of forced ventilation, the acquisition means 3 take the form of an additional temperature sensor 4 appropriately placed within the ventilation system. In the case of natural ventilation, the additional temperature sensor 4 is placed outside the environment. Alternatively, still in the case of natural ventilation, the additional temperature sensor 4 can be omitted. In this case, the acquisition means 3 comprise a communication unit 5 configured to connect to a remote temperature detecting service, e.g. an online weather service.
Optionally, the system 1 comprises a humidity sensor 6 adapted to provide a relative humidity value Rh
Preferably, the system 1 comprises a CO2 concentration sensor 7, adapted to measure the CO2 concentration in the environment.
Optionally, the system 1 comprises a VOC sensor 8 to measure the concentration of volatile organic compounds, particularly of the type emitted by human or animal respiration, but also those of non-biological origin that may be present, such as formaldehyde.
Optionally, the system 1 may comprise one or more pollution sensors 9, adapted to provide one or more of the following measurements: PM 2.5 concentration, PM 5 concentration, PM 10 concentration and nitrogen oxides (NO_x) concentration. If present, pollution sensors 9 are placed in the outer environment. Alternatively, if pollution sensors 9 are not present, the above-indicated measurements can be obtained from online services, which are able to provide such data with reference to a specific place. Optionally, some pollution sensors 9 can also be placed in the inner environment.
Optionally, the system 1 may comprise an activation sensor 20 associated with the ventilation means 101. When the ventilation means 101 are of the natural type, the activation sensor may be, for example, a perimeter sensor attached to a window, thus able to detect the opening and closing thereof.
The system 1 also comprises a control unit 10, which is placed in signal communication with at least the temperature sensor 2 and the acquisition means 3. The control unit 10 will be described below with reference to a plurality of modules. This is only done for the sake of clarity and completeness, but should not be understood as limiting the structure of the control unit 10. The modules described can be realised via software, hardware or a combination thereof. They can also be implemented locally, or distributed over a network.
In detail, the control unit 10 comprises a memory module 11. At the same time as the system 1 is set up, at least one value of significant temperature variation ΔT_s, i.e., a temperature variation which can be obtained by the system 100 when the ventilation means 101 are activated, and a significant variation time t_vs, i.e., the time taken by the system 100 to obtain the significant temperature variation ΔT_s, are preset in the memory module 11.
The control unit 10 further comprises a processing module 12, which is configured to set the tv_on and tv_off times of the ventilation means 101. It should be noted that this data can be used either to control ventilation means 101, i.e. when the system 1 controls it directly, or to predict activation thereof when ventilation means 101 are managed independently.
The control unit 10 also comprises a calculation module 13, which is configured to calculate a number of parameters used in the system 1, and then transmit them to the processing module 12.
In particular, the calculation module 13 can be configured to pre-calculate the activation time tv_on of the ventilation means 101 as a function of the maximum CO2max and restore CO2restore values of the CO2 concentration in the environment. In particular, the maximum value is in particular defined as the value at which the ventilation means 101 are activated, while the restore value is the value at which they are deactivated.
If the system 1 comprises the CO2 concentration sensor 7, the CO2 concentration variation rate when the ventilation means 101 are deactivated v_CO2_off can be calculated from two measurements taken at a predetermined time interval while the ventilation means 101 are deactivated. Similarly, the CO2 concentration variation rate when the ventilation means 101 are activated v_CO2_on can be calculated in the same way while ventilation means 101 are activated.
In more detail, the activation time tv_on of the ventilation means 101 is calculated as follows: $t_{v_on} = \frac{{CO}_{2 MAX} - {CO}_{2 restore}}{v_{{CO}_{2} close}}$
CO2 concentration thresholds can be preset in the memory module 11, or they can be calculated by methods known in the state of the art, e.g. as described in European patent application publication EP 4184071 A1 .
The calculation module 13 can also be configured to pre-calculate the deactivation time tv_off of the ventilation means 101 as a function of the maximum CO2max and restore CO2restore values of the CO2 concentration in the environment and the CO2 concentration variation rate when the ventilation means 101 are activated v_CO2_on. In particular, the deactivation time tv_off of the ventilation means 101 is calculated as follows $t_{v_off} = \frac{{CO}_{2 MAX} - {CO}_{2 restore}}{v_{{CO}_{2} on}}$
It should be noted that the calculation module of the activation tv_on and deactivation tv_off times of the ventilation means 101 can be performed in the same way as above but based on volatile organic compound (VOC) concentration values instead of carbon dioxide concentration values as described above. If both CO2 and VOC concentration sensors are available, both calculation modes can be run in parallel, and it will be possible to choose which value to assign to the activation tv_on and deactivation tv_off times of the ventilation means 101. For example, it is possible to choose the first one in chronological order between the two activation times and the last one between the two deactivation times, so as to ensure that neither threshold is ever exceeded and that both values are brought below the restore threshold.
The calculation module 13 may also be configured to calculate a switch on time t_on of the system as a function of at least the significant variation time t_vs and of the activation time tv_on and/or the deactivation time tv_off of the ventilation means 101. It should be noted that in this case the switch on time t_on of the system is prior to the activation time tv_on of the ventilation means 101.
In a first operating mode, wherein the objective is to maximise comfort within the environment, the switch on time t_on of the system is calculated as $t_{on} = t_{v_on} - [t_{vs} + t_{1 ° C} (T - T_{MIN})]$
Wherein t1°C is the time required to increase the temperature by 1 °C in a 2 °C range of the comfort temperature TC. In the context of this description, the comfort temperature TC is the target temperature of the system 100.
In a second operating mode, designed to maximise energy savings, the switch on time t_on of the system is calculated as $t_{on} = t_{v_off} - t_{vs}$
The calculation module 13 can also be configured to calculate a switch-off time t_boost of the system as a function of at least the deactivation time tv_off of the ventilation means, the inner temperature T, the minimum temperature T_min and a temperature variation rate when the ventilation means are deactivated vT_close. In particular, the switch off time t_boost of the system is calculated as follows in both operating modes: $t_{boost} = t_{v_off} + \frac{(T - T_{MIN})}{v_{Tclose}}$
The control unit 10 further comprises an actuation module 14 configured at least to activate the system 100 upon reaching predetermined conditions and to deactivate it upon reaching the switch off time t_boost of the system. Optionally, the actuation module 14 may be configured to activate and/or deactivate the ventilation means 101.
A method for managing an air-conditioning system 100 of an environment is also part of the present invention. The method comprises the step of detecting an inner temperature T of an environment before activating the ventilation means 101.
The significant temperature variation ΔT_s and the significant variation time t_vs are defined.
The activation time tv_on of the ventilation means 101 is then set. This is done by pre-calculating the activation time tv_on of the ventilation means as a function of the maximum CO2max and restore CO2restore values of the CO2 concentration in the environment and the CO2 concentration variation rate when the ventilation means are deactivated v_CO2_off. Alternatively, the activation of the ventilation means 101 can be detected directly by the activation sensor 20.
The deactivation time tv_off of the ventilation means 101 is set. This operation can be done by pre-calculating the deactivation time tv_off of the ventilation means as a function of the maximum CO2max and restore CO2restore values of the CO2 concentration in the environment and the CO2 concentration variation rate when the ventilation means are activated v_CO2_on.
Optionally, it is possible to calculate the switch-on time of the system t_on as described above, in order to anticipate the activation of ventilation means 101
A switch off time of the system is then calculated as described above.

Claims

Method for managing an air-conditioning system (100) of an environment, wherein the environment is provided with ventilation means (101) of the natural and/or forced type configured to allow air exchange by supplying air at an inlet temperature (T_ext) such that the environment tends to a minimum temperature (T_min) when the ventilation means (101) are activated and the system (100) is deactivated, the method being characterised in that it comprises the steps of:
- detecting an inner temperature (T) of an environment before activating the ventilation means (101);

- defining a significant temperature variation (ΔT_s) that the system (100) can obtain when the ventilation means (101) are activated and a significant variation time (t_vs) as the time taken by the system (100) to achieve the significant temperature variation (ΔT_s);

- setting an activation time (tv_on) for the ventilation means (101);

- setting a deactivation time (tv_off) for the ventilation means (101);

- calculating a switch-off time (t_boost) of the system as a function of at least the deactivation time (tv_off) of the ventilation means, the inner temperature (T), the minimum temperature (T_min) and a temperature variation rate when the ventilation means are deactivated (vT_close).
Method according to the preceding claim, wherein the step of setting the activation time (tv_on) of the ventilation means (101) is performed by pre-calculating the activation time (tv_on) of the ventilation means as a function of maximum (CO2max) and restore (CO2restore) values of the CO2 concentration in the environment and of the CO2 concentration variation rate when the ventilation means are deactivated (v_CO2_off).
Method according to the preceding claim, wherein the step of setting the deactivation time (tv_off) is performed by pre-calculating the deactivation time (tv_off) of the ventilation means (101) as a function of the maximum (CO2max) and restore (CO2restore) values of the CO2 concentration in the environment and of the CO2 concentration variation rate when the ventilation means are activated (v_CO2_on);
Method according to claim 1, wherein the steps of setting the activation time (tv_on) and/or the deactivation time (tv_off) of the ventilation means (101) are performed by detecting the activation and/or deactivation of the ventilation means (101) via an activation sensor (20) associated with the ventilation means (101).
Method according to any one of the preceding claims, characterised in that it comprises the step of calculating a switch-on time of the system (t_on) as a function of at least the significant variation time (t_vs) and the activation time (tv_on) and/or the deactivation time (tv_off) of the ventilation means (101), the switch-on time of the system (t_on) being prior to the activation time (tv_on) of the ventilation means (101).
Control system (1) which can be associated with an air-conditioning system (100) of an environment and configured to perform the method according to any one of the preceding claims, comprising:
- a temperature sensor (2) which can be placed in the environment and configured to detect the inner temperature (T) of the environment before activating the ventilation means (101);

- acquisition means (3) for acquiring an air inlet temperature value (T_ext);

- a control unit (10) placed in signal communication with the temperature sensor (2) and the acquisition means (3), the control unit (10) comprising:

- a memory module (11) wherein the value of the significant temperature variation (ΔT_s) that can be obtained by the system (100) when the ventilation means (101) are activated and a significant variation time (t_vs) as the time required by the system (100) to obtain the significant temperature variation (ΔT_s) are preset;

- a processing module (12) configured to set the activation (tv_on) and deactivation (tv_off) times of the ventilation means (101);

- a calculation module (13) configured to calculate a system switch-off time (t_boost) as a function of at least the deactivation time (tv_off) of the ventilation means, the inner temperature (T), the minimum temperature (T_min) and a temperature variation rate when the ventilation means are deactivated (vT_close)

- an actuation module (14) configured at least to activate the system (100) when predetermined conditions are reached and to deactivate it when the system switch-off time (t_boost) is reached.
System (1) according to the preceding claim, characterised in that it comprises a CO2 concentration sensor (7), the calculation module (13) being configured to pre-calculate the activation time (tv_on) of the ventilation means as a function of maximum (CO2max) and restore (CO2restore) values of the CO2 concentration in the environment and the CO2 concentration variation rate when the ventilation means are deactivated (v_CO2_off).
System (1) according to the preceding claim wherein the calculation module (13) is configured to pre-calculate the deactivation time (tv_off) of the ventilation means as a function of the maximum (CO2max) and restore (CO2restore) values of the CO2 concentration in the environment and the CO2 concentration variation rate when the ventilation means are activated (v_CO2_on).
System (1) according to any one of claims 6 to 8, wherein the calculation module (13) is configured to calculate a system switch-on time (t_on) as a function of at least the significant variation time (t_vs) and the activation time (tv_on) and/or the deactivation time (tv_off) of the ventilation means (101), the system switch-on time (t_on) being prior to the activation time (tv_on) of the ventilation means (101).
System (1) according to any one of claims 6 to 9, characterised in that it comprises an activation sensor (20) associated with the ventilation means (101).