FIELD OF APPLICATION

Embodiments described herein concern a method and a control unit for managing a heat pump and a heat pump.

The method for managing a heat pump is used to manage the heating of a building. The invention also concerns a control unit that executes the method and a heat pump that comprises such a control unit.

In a preferably, but not limiting manner, the method for managing a heat pump, the control unit, and the heat pump may be used in the field of air conditioning of buildings.

BACKGROUND OF THE INVENTION

It is well known that, especially in the last two decades, the issue of energy saving has played a key role in public debate and has also been at the centre of extensive and considerable legislative changes at both international and national levels.

In view of the rapid climatic changes associated with anthropogenic causes, there is an increasing need to limit energy consumption and to give priority to renewable energy sources at the expense of non-renewable ones that are based, for example, on the combustion of hydrocarbons.

Also for this reason, in addition to purely economic reasons, the search for energy-efficient methods and devices has played and continues to play a fundamental role in the world technological landscape.

Among the technological sectors, the building sector is the most energyconsuming sector within the European community and is also the one mostly responsible for carbon dioxide emissions, CO2, into the atmosphere.

In addition, homes or buildings, once populated, contain home appliances and apparatuses or devices that consume energy, most often electrical energy, and need to be air-conditioned in winter by heating and in summer by cooling.

It is clear that homes, or more generally, buildings are responsible for a preponderant part of the energy demand of a nation or of a geographical region.

In addition, with regard to homes or buildings in general, international and national laws impose increasingly stringent limits and increasingly stringent requirements in relation to the energy efficiency and energy consumption of the equipment present and used in the homes or buildings themselves.

In addition, there is an increasing need to get rid of the dependence on hydrocarbon energy sources in order to reduce dependence on producing countries in a state of severe political instability or at risk of conflict.

In particular, with regard to the air-conditioning systems of buildings for the heating or cooling, there is a growing need to abandon air-conditioning systems, mainly the heating systems, which operate by means of gas combustion. For this reason, heat pumps powered by electrical energy and which allow both heating and cooling to be provided to a building have been developed in recent years.

A disadvantage of the prior art is that the heat pumps, since they need electrical energy, indirectly require fossil fuels whose demand needs to be reduced. Another disadvantage of the prior art is that the heat pumps are installed in buildings having different types and qualities of insulation, whereby the same heat pump has a different efficiency depending on the building in which it is mounted and for which it is used.

A further disadvantage of the prior art is that the heat pump usually heats water to a much lower temperature than normal buffers or boilers, so that, if such water is used in a heating system, the times to reach the pre-set ambient temperature for a building are extended compared to a traditional boiler or buffer system.

A further disadvantage of the prior art is that a heating system using a heat pump is usually kept switched on to avoid problems due to the long times required to heat a building.

Yet another disadvantage of the prior art is that the heat pump has a yield dependent on the temperature at which the pump itself is. The lower the ambient temperature, the lower the yield is generally. For this reason, a disadvantage of the prior art is that the heat pump yields less when the ambient temperature is lower, i.e. when the heat pump serves more for heating environments.

A further disadvantage of the prior art is that a heat pump connected, for example, to photovoltaic panels, has at its disposal more electrical energy from renewable sources when the need for such energy is lower. A purpose of the invention is therefore to realize a control unit and a method for improving the yield of a heat pump used for the air conditioning of a building.

Another purpose of the invention is to realize a control unit and a method to make the internal temperature of a building more homogeneous and comfortable.

A further purpose of the invention is to realize a control unit and a method for optimizing the use of electrical energy coming from non-renewable energy sources.

The Applicant has devised, tested and embodied the present invention to overcome the shortcomings of the state of the art and to obtain these and other purposes and advantages.

SUMMARY OF THE INVENTION

The present invention is set forth and characterized in the independent claims.

The dependent claims describe other characteristics of the present invention or variants to the main inventive idea.

In accordance with a first aspect, the invention concerns a method executed by a control unit for managing the operation of a heat pump forming part of a closed hydraulic circuit in which water circulates and further comprising a radiant element, a delivery duct which conveys water to the thermal element and a return duct which conveys the water from the thermal element to the heat pump.

This method comprises the following steps:

- receiving at least one temperature value, TR, measured in correspondence with said return duct;

- comparing the at least one temperature value, TR, with at least one threshold value, TR,P;

- controlling the ignition of said heat pump, if it is determined that the measured temperature value, TR, is lower than the at least one threshold value, T ,P.

According to an example of the invention, controlling the ignition of the heat pump comprises controlling the heat pump to heat the water contained in the closed hydraulic circuit until the value, TR, reaches the threshold value, TR,P.

In accordance with a further example of the invention, the at least one threshold value, T ,P, depends on a time slot in which the method is executed.

In accordance with another example of the invention, the method comprises controlling the switching off or deactivation of the heat pump if it is determined that the measured temperature value, TR, is higher than or equal to the at least one threshold value, TR,P.

In accordance with another example of the invention, the method comprises receiving a value of an external temperature, TE, corresponding to a temperature of an external element from which the heat pump takes heat.

In another example, the method comprises updating the at least one threshold temperature value, TR,P, on the basis of the value of the external temperature, TE.

In a further example, updating the at least one value of the threshold temperature, TR,P, comprises decreasing or increasing the at least one value of the threshold temperature, TR,P, if the value of the external temperature, TE, is respectively higher or lower than a predefined reference value.

In yet another example, receiving the at least one temperature value, T , measured in correspondence with the return duct comprises:

- determining whether an electric power, PSP, generated by a local electrical energy generator, is greater than an electric power, Pu, used by the building, wherein the local generator is an electrical energy generator configured to supply electrical energy to the heat pump;

- determining a difference in electric power, AP, as AP = PSP - Pu, if it is determined that the electric power, PSP, generated by the local generator is greater than the electric power, Pu, used by the building;

- updating the at least one value of the threshold temperature, TR,P, increasing it by a quantity on the basis of the value of the power difference AP.

In a further example, controlling the ignition of the heat pump comprises controlling the ignition of the heat pump, if the difference between the temperature, T , of the return duct is lower than at most 4 degrees Celsius with respect to the at least one value of the threshold temperature TR,P.

In a further example, controlling the ignition of the heat pump comprises activating the heat pump so that a frequency of a heat pump compressor is regulated as a function of the power difference AP, wherein, the greater the power difference AP, the higher the frequency of the compressor.

In accordance with another aspect of the invention, there is provided a control unit comprising:

- a memory unit to store information; - a communication unit to transceive data;

- a processor connected to the memory unit and to the communication unit.

Such a control unit is configured to execute a method for managing the operation of a heat pump.

In accordance with a further aspect of the invention, there is provided a heat pump configured to control the temperature of water circulating in a closed hydraulic circuit comprising the heat pump, a delivery duct fluidically connected to the heat pump and configured to allow a flow of water to reach a radiant element, a return duct configured to allow the flow of water to reach the heat pump after passing through the radiant element. The heat pump comprises a control unit in accordance with the present invention.

An advantage of the invention is to optimize the use of energy from renewable sources, thus decreasing the demand for energy generated from fossil fuels.

Another advantage of the invention is to optimize the yield of a heat pump based on the characteristics of the building in which it is mounted and for which it is used.

A further advantage of the invention is to optimize the ignition of the heat pump on the basis of real heating needs, avoiding that a heating system that uses a heat pump is always maintained switched on to avoid problems due to the long times necessary to heat a building.

Yet another advantage of the prior art is to optimize the yield of a heat pump on the basis of the external temperature.

Another advantage of the invention is to realize a control unit, a heat pump, and a method for improving the yield of a heat pump used for air-conditioning a building.

Another advantage of the invention is to realize a control unit, a heat pump, and a method to make the internal temperature of a building more homogeneous and comfortable.

A further advantage of the invention is to realize a control unit, a heat pump, and a method for optimizing the use of electrical energy from non-renewable energy sources.

DESCRIPTION OF THE DRAWINGS

These and other aspects, characteristics and advantages of the present invention will become apparent from the following description of some embodiments, given as a non-restrictive example with reference to the attached drawings wherein:

- fig. 1 schematically shows a building comprising a heat pump;

- fig. 2 is a simplifying diagram of a heat pump and of a hydraulic system that is thermally connected to said pump;

- fig. 3 is a simplifying diagram of a heat pump and of a hydraulic system that is thermally connected to said pump according to another example of the invention;

- fig. 4 is a simplifying diagram of a control unit;

- fig. 5 is a block diagram of a method for managing a heat pump according to an example of the invention;

- fig. 6 is an exemplary graph of a plurality of threshold temperatures as a function of time;

- fig. 7 is a block diagram of a method for managing a heat pump according to an example of the invention; - fig. 8 is an exemplary graph of a temperature differential as a function of the external temperature according to an example of the present invention;

- fig. 9 is a diagram of electrical and/or hydraulic connections between a heat pump, an electric grid, a local generator and a closed hydraulic circuit, according to an example of the invention; - fig. 10 is a block diagram of a method for managing a heat pump according to an example of the invention.

To facilitate comprehension, the same reference numbers have been used, where possible, to identify identical common elements in the drawings. It is understood that elements and characteristics of one embodiment can be conveniently combined or incorporated into other embodiments without further clarifications.

DESCRIPTION OF EMBODIMENTS

Reference will now be made in detail to the possible embodiments of the invention, of which one or more examples are illustrated in the accompanying figures by way of non-limiting example. The phraseology and terminology used herein is also for non-limiting exemplary purposes.

Figure 1 shows a building 100 which may be a residential building such as a single house, a cottage, a flat or the like, or a commercial or industrial building or the like. The building 100 is electrically connected to the electric grid 102, exemplified in figure 1 with a control unit or a truss, for the supply of electrical energy.

The building 100 may also comprise and/or be electrically connected to a local electrical energy generator 101, hereinafter local generator 101. The local generator 101 is configured, when present, to supply electrical energy to the building 100 in combination with the electric grid 102.

The local generator 101 generates electrical energy using renewable energy sources such as solar radiation energy, mechanical wind energy, mechanical water energy flowing for example in a watercourse, underground thermal energy, or the like.

The person skilled in the art will understand that the local generator 101 may comprise one or more electrical energy generators using the same or different renewable sources.

The building 100 comprises a closed hydraulic circuit 106 comprising an electrically powered heat pump 103 and used for the air conditioning of the building 100, i.e. for heating or cooling the building 100.

The various methods of operation of a heat pump are known to the person skilled in the art. Their detailed description is outside the scope of this invention and, for this reason, is not reported herein.

The heat pump 103, shown schematically in figure 2, is configured to control the temperature of water circulating in the closed hydraulic circuit 106, i.e. to take the water to a predetermined temperature, and to convey it through at least one pipe, duct, or conduit, hereinafter delivery duct 107, towards a thermal element 104 configured to exchange the heat of the water exiting the heat pump 103 with the surrounding environment.

The water, after reaching the thermal element 104, returns to the heat pump 103 through at least one pipe, duct, or conduit, hereinafter return duct 108, where it is returned to the predetermined temperature value.

The heat pump 103, the thermal element 104, the delivery duct 107, and the return duct 108 constitute the closed hydraulic circuit 106 in which the water whose temperature is controlled by the heat pump 103 circulates.

The thermal element 104 is configured to facilitate heat exchange between the water and the thermal element 104 itself or between the water and the environment of the building 100. An environment of the building means the air in the building 100, or a floor, ceiling, wall, or any element of the building 100.

In an option of the present invention, to facilitate heat exchange between the water of the closed hydraulic circuit 106 and the thermal element 104 itself or the environment of the building 100, the thermal element 104 is configured to keep the water therein for as long as possible. The permanence of the water in the thermal element 104 may be regulated by using a duct shaped like a coil, helix, or the like. In another example, the thermal element 104 may be constituted by a radiator, for example a finned radiator, which facilitates heat exchange between the water of the closed hydraulic circuit 106 and the thermal element 104 itself or the environment of the building 100. The two examples of radiant system 104 do not exclude one another and may be implemented in a single solution.

The heat pump 103 may also be connected to a water source, such as, for example, a hydraulic system of the building 100. The heat pump 103 may comprise a tank (not shown in the figures), fluidically connected with the closed hydraulic circuit 106, configured to be filled with water coming from the hydraulic system until a certain pressure is reached after which the flow of water entering the heat pump 103 is stopped manually or automatically through a tap or a valve or the like. Once the determined pressure is reached in the closed hydraulic circuit 106, the heat pump 103 is in operating condition.

The heat pump 103 comprises a duct 103a containing a gas. The duct 103a allows to fluidically connect an expander 103b configured to allow gas expansion, a first heat exchanger 103 c, a compressor 103 d configured to compress the gas, and a second heat exchanger 103e. The assembly of expander 103b, first heat exchanger 103c, compressor 103d, and second heat exchanger 103e constitute a closed fluidic system, i.e. in which the gas circulating therein is neither lost nor extracted, nor added.

In the case where the heat pump 103 is used for heating, it subtracts heat from an external element 109 having a lower temperature and passes it to the water present in the heat pump 103 having a higher temperature.

More in detail, the gas is allowed to expand in the expander 103b and is then made to flow into the first exchanger 103 c where it subtracts heat by virtue of its expansion from an external element 109. The external element 109 is shown in the figure as a duct comprising a fluid circulating in the duct according to verse A. In this example, when the external element 109 is a fluid circulating in a duct, such fluid may be in contact and in thermal balance with a further external element which may be air, water, or soil. In one example, the external element 109 may be water circulating in ducts positioned at least partially underground where the water reaches a thermal balance with the subsoil.

In another example, the external element 109 may be water circulating in ducts positioned at least partially in a basin or watercourse where the water present in the duct reaches a thermal balance with the water present in the basin or watercourse.

In other examples, the external element 109 is simply the air present outside the building 100.

The person skilled in the art will understand that the examples given above are not limiting the invention and that other solutions known from the state of the art can be used.

In all the examples reported, the person skilled in the art will know ways, methods, and devices suitable for implementing the first exchanger 103 c so as to allow heat exchange between the external element 109 and the gas circulating in the closed fluidic system of the heat pump 103. In a non-limiting example, the first exchanger 103c may comprise a coil wound around a tube in which water passes in contact and thermal balance with the external element 109. In another nonlimiting example, the first exchanger 103 c may comprise a radiator in thermal contact with the external element 109. The person skilled in the art will understand that other methods and configurations of the first exchanger 103 c that allow a heat exchange between the gas present in the fluidic system of the heat pump 103 and the external element 109 can be used within the scope of the present invention.

After the first exchanger 103c, the gas is compressed by the compressor 103d and moves towards the second heat exchanger 103 e. Here the compressed gas gives its heat to the water contained in the closed hydraulic circuit 106 connecting the heat pump 103 and the thermal element 104. The gas comes into thermal contact with the water circulating in the closed hydraulic circuit 106 through a coil, a radiator, or the like. Thereafter, the gas returns to the expander 103b where the thermodynamic cycle allowing heat exchange restarts. In this way, when the heat pump 103 is in operation, there is a constant heat exchange between the external element 109 and the gas present in the closed fluidic system of the heat pump 103 which in turn releases heat to the water circulating in the closed hydraulic circuit 106.

The water circulating in the closed hydraulic circuit 106 can be brought to a pressure ranging from about 0.5 to 2.5 atm, corresponding to 49 and 245 Pa, respectively.

The water releases heat to the thermal element 104 which releases it to the environment of the building 100. The release of heat into the environment of the building 100 occurs by direct contact between the thermal element 104 and the air present in the building 100 or by indirect contact wherein the thermal element 104 releases heat to an element of the building 100, such as the floor, ceiling, walls, and the like. In turn, the element of the building 100 releases heat to the air present in the building 100.

The thermal element 104 is usually built to retain as long as possible the water circulating in the closed hydraulic circuit 106 and/or to allow a rapid heat exchange between the water and the environment of the building 100. This is achieved by a thermal element 104 comprising, for example, a coil, a lamellar radiator, and the like.

The thermal element 104 is provided with a thermal inertia due to which the thermal element needs a certain amount of time to reach thermal balance with the water circulating in the closed hydraulic circuit 106.

The inertia of the thermal element 104 depends on the materials with which the thermal element is built, its conformation, the presence of a tank of accumulation of the water circulating in the closed hydraulic circuit 106, and the like.

After releasing heat to the thermal element 104, the water circulating in the closed hydraulic circuit 106 returns, through the return duct 108, to the heat pump 103. Here it comes into indirect contact with the gas present in the second heat exchanger 103e where it is heated again to restart the cycle identified by the arrow B.

In this way, the repetition of the cycle B allows a certain quantity of heat to be continuously subtracted from the external element 109 and transferred to the environment of the building 100 when the heat pump 103 is in operation.

In one example, schematically shown in figure 3, the closed hydraulic circuit 106 may comprise at least one between a tank 110 configured to store the water heated by the heat pump 103 and a manifold 111 configured to manage the flow of water to and from the thermal element 104. The tank 110 may be external to or internal to the thermal element 104.

The closed hydraulic circuit 106 shown in figures 2 and 3 comprises at least one sensor 112 configured to detect data relative to the water flowing in the closed hydraulic circuit 106 itself. The at least one sensor 112 may be chosen from a thermometer, a pressure gauge, a barometer, a flow meter, and the like.

In one example of the invention, the at least one sensor 112 is a thermometer mounted in correspondence with the return duct 108 and configured to detect the temperature of the water after it has passed through the thermal element 104. The at least one sensor 112 is connected to a control unit 10 in turn connected to the heat pump 103 to manage its operation. It will be clear to the person skilled in the art that the connections between sensor 112, control unit 10, and heat pump 103 can be obtained by physical medium, wire, cable, conductive trace, and the like or by wireless technology, such as, for example, Bluetooth, Wi-Fi, LTE, short- , medium-, and long-range radio frequency connection, and the like.

The person skilled in the art will understand that any connection capable of communicating an electromagnetic signal can be used in the present invention.

In the example where the sensor 112 is a thermometer, it sends data relative to the temperature of the water flowing in the return duct 108 to the control unit 10. With reference to figure 4, the control unit 10 comprises at least one processor 11, a communication unit 12 for enabling communication between the processor 11 and an external device or between the processor 11 and an internal unit of the control unit 10, for example between the processor 11 and a memory unit 13.

The control unit 10 further comprises a memory unit 13 for recording data and operating commands to execute a code, possibly one or more electronic databases.

The control unit 10 may be internal or external to the heat pump 103. If the control unit 10 is external to the heat pump 103, the control unit 10 and the heat pump 103 are connected so as to make it possible to transceive electrical or electromagnetic signals through a wire, a cable, a conductive trace or through any wireless communication method. The communication between the control unit 10 and the heat pump 103 may take place both by transmission of electrical signals via physical medium, such as a cable, a wire, and the like, and wirelessly, using communication protocols at short range, such as inductive coupling, capacitive coupling, NFC, RFID, and the like, at medium range, such as Bluetooth and the like, at long range by using Wi-Fi or radio frequency communication. The communication can also take place via LAN internet connection or wirelessly.

Optionally, the control unit 10 comprises an interface unit, not shown in the figures. The interface unit may be any element or device adapted to provide an operator with information, such as visual, tactile, sound, etc. The interface unit may be adapted to receive input from a user and to transmit said input to the processor 11 via the communication unit 12. The interface unit may be constituted by a screen provided with data inputting means, such as a keyboard, a mouse, and the like, a touch-sensitive screen, or the like.

The interface unit may also be an element external to the control unit 10 that communicates with it through the methods and the protocols, via physical medium or wirelessly, set forth above. The interface unit may be implemented in a smartphone, a tablet, a computer, a portable or fixed data processing and/or computing device, and the like.

The processor 11 is configured to control each individual unit of the control unit 10 and to execute commands saved permanently or temporarily in the memory unit 13 and/or to process data and/or information saved in said memory unit 13.

The memory unit 13 is constituted by any physical medium that allows the storage of data such as a hard disk, a solid-state memory, an optical memory medium, and the like, or any other form of digital, local or remote storage. The memory unit 13 may also be a unit external to the device and connected to the processor 11 via the communication unit 13. Said memory unit 13 external to the control unit 10 may also be comprised in an external server (not shown in the figures) and connected to the processor 11 through said communication unit 12 via the internet.

Software and data instructions may for example be encoded and stored in the memory unit 13 to command the processor 11. The memory unit 13 may also contain information relative to one or more threshold temperature values.

Other auxiliary circuits, not shown in the figures, may be connected to the processor 11 to assist the processor 11 in a conventional manner. The auxiliary circuits may include for example at least one of: cache circuits, power circuits, clock circuits, input/output circuitry, sub-systems, and the like. A program (or computer instructions) readable by the processor 11 and stored in the memory unit 13 may determine which tasks are achievable in accordance with the method according to the present description. In some embodiments, the program is a software readable by the processor 11. The communication unit 12 is configured to enable the processor 11 to communicate with the other units of the control unit 10 or with electronic devices or external units. The communication may take place both by transmission of electrical signals via physical medium, such as a cable, a wire, and the like, and wirelessly, using communication protocols at short range, such as inductive coupling, capacitive coupling, NFC, RFID, and the like, at medium range, such as Bluetooth and the like, at long range by using Wi-Fi or radio frequency communication. The communication can also take place via LAN internet connection or wirelessly.

Below reference will now be made to the processor 11 and to the control unit 10 interchangeably. The person skilled in the art will understand, if reference were made to the processor 11 , which elements of the control unit 10 are involved in the execution of each function.

The processor 11 is configured to receive, via the communication unit 12, data relative to the heat pump 103 and/or to the water flowing in the closed hydraulic circuit 106 obtained through one or more sensors, such as the at least one sensor 112.

Such data may be measurement values of physical quantities relative to the water flowing in the closed hydraulic circuit 106, such as a temperature, a pressure, a speed, a flow rate, a flow, and the like. In particular, the processor 11 is configured to receive a temperature value TR measured by the at least one sensor 112 installed on the return duct 108 and relative to the temperature of the water flowing in the return duct 108. The temperature value T may represent the direct measurement of the water obtained by the at least one sensor 112 installed in direct contact with the water flowing in the return duct 108. Alternatively, the temperature value TR may represent the measurement of the temperature of the return duct 108. In this case, the temperature value TR is processed by the at least one sensor 112 or the control unit 10 to obtain the measurement of the temperature of the water flowing in the duct 108.

The person skilled in the art will understand that when the closed hydraulic circuit 106 comprises a plurality of sensors 112, each of the sensors 112 can transmit a measured temperature value of the return duct 108 to the control unit 10.

The plurality of measured values of the temperature of the return duct 108 are processed by the control unit 10 to obtain a single value of the temperature TR, for example, by making a statistical average, a weighted average, a median, a mode, and the like of the plurality of measured values of the temperature of the return duct 108. In summary, reference will be made hereinbelow to a single measured temperature value TR. The average technician will understand that the invention also comprises the case where the closed hydraulic circuit 106 comprises a plurality of sensors 112 that measure and send to the control unit 10 a plurality of measured values of the detected temperature relative to the water flowing in the return duct 108.

A method for managing the heat pump 103 implemented by the control unit 10 is shown in figure 5. This method comprises the following steps.

In a first step SI 00, the control unit 10 receives at least one temperature value TR measured by the at least one sensor 112 in correspondence with the return duct 108 and relative to the temperature of the water flowing therein, wherein the at least one sensor 112 is a thermometer or any sensor capable of detecting a temperature. In summary, the temperature TR will hereinafter be referred to as the temperature of the return duct 108 despite being the temperature of the water contained in the return duct 108.

In a second step SI 10, the control unit 10 compares the measured temperature value TR of the return duct 108 with at least one predefined value of threshold temperature TR,P.

With reference to figure 6, the at least one predefined value of threshold temperature TR,P may be stored in the memory unit 13 as a predefined data. Optionally, the at least one predefined value of threshold temperature TR,P may be manually entered by an operator through an interface unit. According to another example, the at least one predefined value of threshold temperature TR,P may be received by the control unit 10 from a server or an external electronic device.

The at least one predefined value of threshold temperature TR,P may depend on the daily time slot in which the method is executed. In such a case, the memory unit 13 stores a plurality of threshold temperature values TR,P comprising, for example, four values TR,PI, TR,P2, TR,P3, and TR,P4 corresponding to the time slots relative to night, morning, afternoon, and evening hours, respectively.

The plurality of threshold temperature values TR,P defines a curve 113 as a function of the time of day. The curve 113 may be preset on the basis of, for example, at least one of the following factors: a characteristic of operation of the heat pump 103, a model of the heat pump 103, a type of the heat pump 103, an energy class of the building 100 in which the heat pump 103 is located, a geographical location of the building 100, a climatic type of the location where the building 100 is located, information relative to the construction materials of which the building 100 is composed, a custom of the users of the building 100, a number of users of the building 100, an intended use of the building 100, a temporal pattern of occupation of the building 100 by users of the building 100, and an identity of the people present in the building 100, wherein the identity of the people present in the building is detected by RFID identification techniques, by measuring biometric characteristics, or by personal identification.

It will be clear to the person skilled in the art that the number of time slots and therefore of threshold temperature values TR,P is not limited to four, as shown in figure 6, but can be any number greater than or equal to one. If during the comparison step SI 10 it is determined that the measured temperature value TR of the return duct 108 is greater than or equal to the at least one threshold temperature value TR,P relative to the time slot in which the method is executed, the method envisages measuring again, by the at least one sensor 112, the temperature TR of the water in correspondence with the return duct 108 and transmitting to the control unit the measured temperature value TR to restart the method.

Conversely, if during the comparison step SI 10 it is determined that the measured temperature value TR of the return duct 108 is lower than the at least one threshold temperature value TR,P relative to the time slot in which the method is executed, the method envisages the step of ignition SI 20 of the heat pump 103 to take the temperature TR of the measured water in correspondence with the return duct 108 to the value of the threshold temperature TR,P relative to the time slot in which the method is executed. During this step, the control unit 10 controls the maintenance of the heating functionality of the heat pump 103 until the value TR reaches the threshold value TR,P.

In one example, the control unit 10 directly controls the activation of the heat pump 103 by sending a command signal to the heat pump 103. In another example, the control unit 10 sends information to the heat pump 103 which processes it and activates on the basis of the information processing.

In all these examples, when the control unit 10 determines that the measured temperature value TR relative to the water flowing in the return duct 108 is lower than the threshold temperature value TR,P relative to the time slot in which the method is executed, the control unit 10 controls the ignition of the heat pump 103 to heat the water contained in the closed hydraulic circuit 106 and take the temperature thereof to the value TR,P.

The heat pump 103 remains switched on as long as the measured temperature value TR of the return duct 108 is lower than the threshold temperature value TR,P relative to the time slot in which the method is executed. When this condition no longer occurs, the control unit 10 controls the switching off or deactivation of the heat pump 103 which, therefore, will no longer heat the water contained in the closed hydraulic circuit 106.

A second method for managing the heat pump 103 executed by the control unit 10 is shown in figure 7. The method is similar to the method described in relation to figure 5 which is referred to for the details of the steps in common.

The method envisages a step SI 00a of receiving, by the control unit 10, an external temperature value TE. The external temperature TE corresponds to the temperature of the external element 109 from which the heat pump 103 takes the heat to supply it to the water flowing in the closed hydraulic circuit 106.

When the heat pump 103 subtracts heat from the air, the external temperature TE corresponds to the ambient temperature outside the building 100.

In one example of the invention, the external temperature TE corresponds to the ambient temperature outside the building 100 measured in the morning, optionally in an interval between 05am and 07am in the morning, advantageously at 06am, preferably before sunrise, even more preferably at a time corresponding to the coldest hour of the day, according to the current time zone. The measurement of the external temperature TE made in the morning allows to obtain a temperature value that is not influenced, for example, by the solar rays that hit the thermometer or the temperature detector.

In this example, the external temperature TE can be measured either promptly, that is, only one temperature value can be measured, or it can correspond to the average of a plurality of temperature values measured at the aforementioned times.

When the heat pump 103 subtracts heat from a water tank, the external temperature TE corresponds to the temperature of the water present in the water tank.

When the heat pump 103 subtracts heat from the ground or subsoil, the external temperature TE corresponds to the temperature of the ground or of the subsoil.

In all the above examples, the temperature is measured by special sensors or instruments. It will be clear to the person skilled in the art which instruments to use, for example a thermometer, an infrared ray sensor, or the like, to adequately measure the external temperature TE. The method envisages a step of receiving SI 00 the temperature value of the water contained in the return duct 108 similar to the reception step SI 00 of the method described in relation to figure 5.

In a third step SI 04, the control unit 10 updates the at least one threshold temperature value TR,P relative to the time slot in which the method is executed on the basis of the measured value of the external temperature TE.

The heat pump 103 has a yield (efficiency) that depends on the temperature of the external element 109 from which the heat is subtracted. To increase the efficiency of the heat pump, the threshold temperature value TR,P, relative to the time slot in which the method is executed, is updated as a function of the measured value of the external temperature TE.

The measured value of the external temperature TE is compared to a reference value TREF of the external temperature which depends on an intrinsic characteristic of the heat pump 103, mostly linked to the yield of the heat pump 103 as a function of the temperature of the external element 109 from which to subtract the heat, and/or on construction characteristics of the building 100 to be heated.

By way of example, figure 8 is a graph of a temperature difference value AT as a function of the value of external temperature TE. The reference value TREF of the external temperature corresponds to said temperature value below which the preset curve 113 of the at least one threshold temperature value TR,P, is not updated by the control unit 10. The reference value TREF of the external temperature may depend on one of the following factors: a characteristic of operation of the heat pump 103, a model of the heat pump 103, a type of the heat pump 103, an energy class of the building 100 in which the heat pump 103 is located, a geographical location of the building 100, a climatic type of the location where the building 100 is located, information relative to the construction materials of which the building 100 is composed, a custom of the users of the building 100, a number of users of the building 100, an intended use of the building 100, a temporal pattern of occupation of the building 100 by users of the building 100, and an identity of the people present in the building 100, wherein the identity of the people present in the building is detected by RFID identification techniques, by measuring biometric characteristics, or by personal identification.

Conversely, when the measured external temperature TE is higher than the reference value T EF the control unit 10 updates the at least one threshold temperature value TR,P, SO as to lower it by a quantity AT. In one example, the quantity AT is subtracted from each of the plurality of threshold temperature values TR,P. In another example, the threshold temperature values TR,P are adjusted by subtracting a quantity AT(t)=c(t)-AT where c(t) is a factor that depends on the time slot associated with each single value of the plurality of threshold temperature values TR,P.

In an example of the invention, the reference value TREF corresponds to the value of a reference curve 114 as a function of the external temperature value TE, whereby, at each external temperature value TE, the curve 113 of the plurality of threshold temperature values TR,P is modified, by subtraction, by a value AT in accordance with the modes described above.

In general, the lower the value of the external temperature TE the higher the value of the threshold temperature TR,P. More in detail, the lower the value of the external temperature TE compared to the reference value of the external temperature, the higher the value of the threshold temperature TR,P. Likewise, the higher the value of the external temperature TE compared to the reference value of the external temperature, the lower the value of the threshold temperature TR,P. When the external element 109 is the air present outside the building 100, the lower the external temperature TE the higher the value of the threshold temperature TR,P.

In this way, on a cold day, when the external temperature, TE, is low with respect to a predefined value, the heat pump 103 is activated to reach the at least one higher threshold temperature value, TR,P. Conversely, on a hot day, when the external temperature, TE, is high with respect to the predefined value, the heat pump 103 is activated to reach the at least one lower threshold temperature value, TR,P.

Subsequently, the method continues with steps S 110 and S 120 which have been described above relatively to figure 5 to which reference is made without describing them in detail for the sake of synthesis.

In figure 9 there are schematically shown the electric grid 102 and the local generator 101 connected with the heat pump 103 in fluidic connection with the closed hydraulic circuit 106.

As already discussed above, the local generator 101 is configured to generate a quantity of electrical energy and to supply it directly to the building 100.

An example of a local generator 101 consists of photovoltaic panels mounted on the roof of a building or on a land adjacent to the building itself. Or, the local generator 101 may be constituted by wind turbines for domestic use placed in the vicinity of the building 100 to which the generated electrical energy is transferred. In another example, the local generator 101 may be constituted by an electrical energy generation system that exploits geothermal energy.

In other words, the local generator 101 generates electrical energy which is transferred to the building 100 and is possibly introduced into the electric grid 102, when the electric power generated by the local generator 101 exceeds the momentary energy requirement of the building 100, i.e. the electric power needed by the building 100.

By way of example and for clarity of explanation, reference will be made in the following paragraph to the state of the art for which the following paragraph should not be interpreted as a description of the object of the present invention. In the state of the art, if the electric power supplied by a local generator is not sufficient to meet the energy requirement of a building, the remaining part of the electric power required to meet the energy requirement of the building is obtained from an electric grid. Conversely, if the electric power supplied by the local generator is greater than the energy requirement of the building, the excess part of the electric power is fed into the electric grid. A disadvantage of this approach consists in that the energy produced by the local generator is not used for the operation of the devices present in the building. An electrical management unit 200 is electrically connected to the electric grid 102 and to the local generator 101. The electric management unit 200 is configured to monitor the quantity of electric power supplied to the heat pump 103 and/or to the building 100 by the electric grid 102 and/or by the local generator 101.

The electric management unit 200 transmits data relative to the electric power absorbed by the heat pump 103 and/or by the building 100 in general from the electric grid 102 and/or from the local generator 101 to the control unit 10. Other information that the electrical management unit 200 may transmit to the control unit 10 may comprise a potential difference value and/or a current value associated with the absorbed electrical energy, from the heat pump 103 and/or from the building 100, from the electric grid 102 and/or from the local generator 101.

The transmission of the data from the electrical management unit 200 may take place in one of the ways set forth above, i.e. via physical medium such as cable, wire, conductive trace or via wireless transmission, such as Bluetooth, Wi-Fi, short-, medium-, or long-range radio frequencies, and the like. The way to determine how much electric power is supplied by the electric grid 102 and/or by the local generator 101 is outside the context of this invention and is considered part of the technical knowledge of the person skilled in the art. For these reasons it will not be explained here in detail.

The local generator 101 may be at least one, typically a plurality, of photovoltaic panels that transform the radiant energy of the sun into electrical energy.

In such a case, the electrical energy produced by the local generator 101 varies on the basis of the solar irradiation, time of day, period of the year, and other similar or the like parameters. In other words, the electrical energy produced by the local generator 101, when this consists of at least one photovoltaic panel, depends on the quantity of solar radiation absorbed by the at least one photovoltaic panel.

It will be obvious that the period in which the local generator 101 produces the greatest quantity of electrical energy, during the day, corresponds to the period in which the building is most irradiated by the sun and therefore to the period in which the energy needed to heat the building is minimal.

In figure 10 there is shown a third method for managing the heat pump 103 when it is powered by the electric grid 102 and/or by the local generator 101. The method is similar to the methods described in relation to figures 5 and 7 to which reference is made for details of the common steps.

The method shown in figure 10 is used when the heat pump 103 is powered by both the grid 102 and by the local generator 101. However, it will be clear to the person skilled in the art that a heat pump 103 powered by the electric grid 102 and by the local generator 101 can also be managed using the methods described in relation to figures 5 and 6.

In the method relative to figure 10, the method optionally comprises a step of measuring SI 00a an external temperature TE. The external temperature TE corresponds to the temperature of the external element 109 from which the heat pump 103 takes the heat to supply it to the water flowing in the closed hydraulic circuit 106.

The measuring step SI 00a of an external temperature TE corresponds to the measuring step SI 00a of the method described in relation to figure 7. The details and the advantages of measuring the external temperature TE will not be repeated here for the sake of synthesis.

The method further provides for determining, in a first determination step S200, by means of the control unit 10, whether an electric power PSP generated by the local generator 101 is greater than an electric power Pu used by the building 100. The electric power Pu corresponds to the energy requirement of the building 100, i.e. the total electric power absorbed by all the devices, units and apparatuses present in the building.

The person skilled in the art will understand that the determination of the electric power PSP generated by the local generator 101 is obtained by calculating the average between a plurality of values measured over a period of time ranging from 5 to 15 minutes to avoid that a sudden fogging of an otherwise clear sky causes the heat pump to switch on due to a generation of electric power that is temporarily low by, for example, photovoltaic panels. The person skilled in the art will also understand that any method for avoiding an incorrect determination of the electric power PSP generated by the local generator 101 is usable for the purposes of the present invention such as, for example, executing a smoothing of the curve of the electric power values PSP measured by, moving average, Gaussian smoothing, exponential smoothing, filters, splines, and the like. The data on the electric power Psp generated by the local generator 101 and on the electric power Pu used by the building 100 are transmitted to the control unit 10 by the electric management unit 200.

If it has been determined in the determination step S200 that the electric power PSP generated by the local generator 101 is greater than the electric power Pu used by the building 100, the control unit 10 is configured to determine, in step S210, an electric power difference AP corresponding to AP = PSP - Pu.

If, on the contrary, it has been determined in the determination step S200 that the electric power PSP generated by the local generator 101 is lower than or equal to the electric power Pu used by the building 100, the method envisages repeating after a certain time interval, comprised between 1 second and a few minutes, the determination step S200.

The method also comprises a receiving step SI 00 in which the control unit 10 receives at least one temperature value TR measured by the at least one sensor 112 in correspondence with the return duct 108. Step S 100 corresponds to the receiving steps SI 00 of the methods described in relation to figures 5 and 6 referred to and which will not be described here in detail for the sake of synthesis.

The method provides an updating step SI 04 in which the at least one threshold temperature value TR,P is updated on the basis of the value of the power difference AP. More in detail, in the step of updating S 104 the at least one value of the threshold temperature TR,P is increased by a certain quantity in a manner directly proportional to the value of the power difference AP.

Furthermore, updating SI 04 the at least one value of the threshold temperature, TR,P, also comprises decreasing or increasing the at least one value of the threshold temperature, TR,P, if the value of the external temperature, TE, is respectively higher or lower than a predefined reference value. For details, please refer to figure 7 and its description. The at least one predefined value of threshold temperature TR,P corresponds to the at least one predefined value of threshold temperature TR,P described in relation to the methods shown in figures 5 and 7, but in which TR,P is also updated on the basis of the power generated by the local generator 101.

The at least one predefined value of threshold temperature TR,P may be stored in the memory unit 13 as predefined data, optionally, may be manually entered by an operator through an interface unit, according to another example, may be received by the control unit 10 from a server or an external electronic device.

The at least one predefined value of threshold temperature TR,p may depend on the time slot at which the method is executed. For example, the values TR,PI, TR,P2, TR,P3, and TR,P4 correspond to the time slots relative to night, morning, afternoon, and evening hours, respectively.

It will be clear to the person skilled in the art that the number of time slots and therefore of threshold temperature TR,P is not limited to four but can be any number greater than or equal to one. Subsequently, the method envisages a comparison step SI 10 in which the measured temperature value TR of the return duct 108 is compared with at least one predefined value of threshold temperature TR.P relative to the current time slot in which the method is executed.

If during the comparison step SI 10 it is determined that the measured temperature value TR of the return duct 108 is greater than or equal to at least one threshold temperature value TR,P relative to the time slot in which the method is executed, the method envisages repeating the step to determine S200 whether the electric power PSP generated by the local generator 101 is greater than the electric power Pu used by the building 100 and then repeating the method. Conversely, if during the comparison step SI 10 it is determined that the measured temperature value TR of the return duct 108 is lower than the value of threshold temperature values TR,P relative to the time slot in which the method is executed, the method envisages the step of ignition S250 of the heat pump 103. The control unit 10 sends a command signal to the heat pump 103 to activate it. In another example, the control unit 10 directly controls the activation of the heat pump 103. In yet another example, the control unit 10 sends an ignition information to the heat pump 103 that processes it. Based on the processing of the ignition information, the heat pump 103 is activated.

In all of these examples, when the control unit 10 determines that the measured temperature value TR of the return duct 108 is lower than the threshold temperature value TR,P relative to the time slot in which the method is executed, the control unit 10 controls the ignition of the heat pump 103 to heat the water contained in the closed hydraulic circuit 106.

Optionally, the heat pump 103 is activated if the difference between the temperature TR of the return duct 108 and the at least one threshold temperature value TR,P is at most 4 degrees Celsius (or Kelvin).

The heat pump 103 remains switched on as long as the measured temperature value TR of the return duct 108 is lower than the threshold temperature value TR,P or relative to the time slot in which the method is executed. When this condition no longer occurs, the control unit 10 controls the switching off or deactivation of the heat pump 103 which, therefore, will no longer heat the water contained in the closed hydraulic circuit 106. In executing this method, the control unit 10 is configured to activate the heat pump 103 on the basis of the power difference AP. In other words, the control unit 10 activates the heat pump 103 so that the frequency of the compressor 103 d is adjusted as a function of the power differential AP, whereby, the greater the power differential AP, that is, the greater the electric power generated by the local generator 101 that exceeds the energy requirement of the building, the power used by the building Pu, the greater the frequency of the compressor 103d.

In this way, the excess electric power generated by the local generator 101, AP, is not introduced into the grid and is used to generate hot water that is stored in the closed hydraulic circuit 106, in particular in the thermal element 104. The thermal element 104 has a certain thermal inertia, that is, it takes it a certain amount of time to change its temperature. The method described herein exploits such thermal inertia and uses the excess electric power AP, generated by the local generator 101, to heat the water present in the closed hydraulic circuit 106 which will heat the thermal element 104 to store thermal energy in the building 100.

The heat pump 103 remains switched on as long as the measured temperature value TR of the return duct 108 is lower than the threshold temperature value T ,P relative to the time slot in which the method is executed. When this condition no longer occurs, the method envisages the step of deactivation S260 of the pump, i.e. the control unit 10 controls the switching off or the deactivation of the heat pump 103 which, therefore, will no longer heat the water contained in the closed hydraulic circuit 106.

The at least one value TR,P in addition to being determined as described above may also depend on at least one of an energy class of the building 100, a geographical location of the building 100, a climatic type of the location where the building 100 is located, information relative to the construction materials of which the building 100 is composed, a custom of the users of the building 100, a number of users of the building 100, an intended use of the building 100, a temporal pattern of occupation of the building 100 by users of the building 100, and an identity of the people present in the building 100, wherein the identity of the people present in the building is detected by RFID identification techniques, by measuring biometric characteristics.

In the following claims, the references in parentheses have the sole purpose of facilitating reading and must not be considered as limiting factors as regards the scope of protection underlying the specific claims.