METHOD FOR CONTROLLING THE OPERATION OF A HEAT PUMP

Description

technical field

[0001] The present invention relates to the field of heat pumps. More particularly, it relates to a method for controlling the operation of such heat pumps. Previous technique

[0002] To meet a consumer's simultaneous demand for heating and cooling, a water-to-water heat pump system is commonly used. This system can simultaneously heat a hydraulic flow at one interface—specifically, the passage between the pump's condenser terminals—and cool a second hydraulic flow at a second interface—specifically, the passage between the pump's evaporator terminals. When both heating and cooling are used to meet demand, the heat pump is referred to as a... "thermofrigopump".

[0003] To meet heating and cooling demands, the heat pump alternates between different, mutually exclusive production modes: (i) heating only, (ii) cooling only, and (iii) simultaneous heating and cooling, the latter being called "heat pump mode." Document FR 3009071A1 describes such a heat pump.

[0004] Typically, the triggering of one of the three modes above is done by comparing the instantaneous temperature measured in the buffer tanks to which the pump is connected with predefined thresholds for each buffer tank.

[0005] However, this control method, based on instantaneous temperature measurement of the buffer tanks, is not entirely satisfactory. Dependent on the relative heating and cooling loads, it tends to favor none of the three modes, simply retrieving sensor data at a given moment and acting accordingly. For simultaneous heating and cooling demands, it is therefore not uncommon to see production alternate between the first and second modes. Yet, from an energy perspective, and to limit the number of heat pump activations, it is preferable to prioritize the heat pump / refrigerator mode.

[0006] US10378805 B2 describes a model-based predictive control (MPC) method for determining an optimal temperature setpoint for the operation of a heat pump. The heat pump is used in combination with an electric resistance heating system. This document describes only the heat production.

[0007] US7905103 describes the control of a refrigeration system using future load prediction to optimize compressor start / stop times. This document relates solely to refrigeration production.

[0008] CN 105937823 B describes the control of a heat pump applied to the heating of a greenhouse, by predicting the associated demand using recent historical data. This document describes only the heat production.

[0009] The solutions proposed in the documents above do not concern the combined production of heat and cold and do not address the problem of optimizing the operation of a heat pump.

[0010] There is therefore a need to improve the control of a heat pump of the thermofrigopopump type, in order to improve its performance, in particular energy efficiency, while adapting as best as possible to the needs of users. Description of the invention

[0011] The invention meets this need through a method of controlling the operation of a heat pump connected to hot and cold buffer tanks, capable of operating according to at least a first mode of heat production only, a second of cold production only and a third of combined cold and heat production, the triggering of the different modes taking place at a given instant t as a function of the measured temperatures of the buffer tanks and at least one piece of information representative of a future need for heat or cold production for the buffer tanks.

[0012] The control of the heat pump then takes into account not only the instantaneous temperature measurement in the buffer tanks, but also the future heating or cooling requirements. The process according to the invention thus makes it possible to select the most energy-efficient production mode; moreover, the invention can reduce the number of operating hours and / or the number of starts of the heat pump compared to a conventional control method, thereby delaying the aging of its components.

[0013] The indicator(s) are preferably generated from the observation of the past operation of the heat pump over a time window which is advantageously of relatively short duration, as detailed below. Heat pump refrigerator

[0014] The heat pump is preferably a water / water type heat pump.

[0015] By "heat source""It is necessary to understand that the source must be sufficiently stable in temperature. The thermal source is preferably a geothermal field. Other sources can be used, for example: a lake, an aquifer, or even an energy network."

[0016] The heat pump is preferably a six-pipe heat pump. "six-pipe heat pump" This refers to a heat pump potentially connected to the supply and return circuits of the heat source, the cold buffer tank, or the hot buffer tank. Such a heat pump allows, through a set of controlled valves, the use of different hydraulic configurations as needed, by dynamically modifying the production scheme. This dynamic modification can be achieved by actuating three-way valves located between the heat pump and the various buffer tanks, as well as between the heat pump and the heat source.

[0017] In the most typical control scenario, the different production modes of the heat pump are mutually exclusive at any given time. The heat pump therefore alternates between these different production modes to meet a given heating and / or cooling demand.

[0018] The demand for heat corresponds, for example, to a demand for domestic hot water and / or a demand for heating.

[0019] The demand for cooling corresponds, for example, to a demand for air conditioning, cooling, and / or a demand for chilled water, particularly in the context of industrial processes, for example in laboratories, or for hospitals. Users

[0020] Users of the cold and / or hot products may include residential or commercial buildings such as hospitals, industrial sites, laboratories, or even museums. Future need

[0021] The future need for heating or cooling production can be predicted by estimating at least one future temperature value in the corresponding buffer tank and by comparing the estimated temperature value(s) with at least one setpoint temperature for heating or cooling production.

[0022] In a preferred embodiment, the future need for heat or cold production is estimated from past observation of the temperature in the corresponding buffer tank.

[0023] In this embodiment, the future need for heating or cooling can be estimated by: determination of a time function representing the evolution over time of the temperature in the corresponding buffer tank, based on past observation of the temperature in said tank, estimation of at least one future value of the temperature in the corresponding buffer tank over a future time horizon, from the time function, and by comparison of the temperature value(s) thus estimated with at least one setpoint temperature for the production of heat or cold.

[0024] The estimated temperature value(s) correspond advantageously to the value(s) taken by the time function over the future time horizon.

[0025] The time function is advantageously chosen to best approximate the evolution of the temperature observed over a past time horizon.

[0026] The time function can be a polynomial function of degree greater than or equal to 1, preferably of degree equal to 1. The use of the polynomial function of degree 1 allows a lightweight and easier implementation on a physical controller.

[0027] The time function can be determined by a regression method on the past observation.

[0028] Regression is preferably linear and is preferably performed by affine regression or by a least squares method. Alternatively, linear regression is performed by a method other than least squares, such as the maximum likelihood method or the Bayesian inference method.

[0029] The time function can also be obtained by a non-linear regression method, such as neural networks, spline interpolation, or a kernel method.

[0030] The values ​​of the past and future time horizons are advantageously linked to the hydraulic sizing of the whole, in particular the inertia of the buffer tanks and the associated temperature dynamics.

[0031] As an example, the future time horizon is between 5 min and 3 h, better between 5 min and 1 h, even better between 10 min and 30 min, especially around 15 min.

[0032] The past time horizon is, for example, between 5 minutes and 3 hours, better between 5 minutes and 1 hour, even better between 10 minutes and 30 minutes, specifically around 15 minutes. This past time horizon preferably includes the given instant t.

[0033] Preferably, the past and future horizons have roughly the same widths. Setpoint temperatures

[0034] The setpoint temperatures for the production of heat and cold, designated respectively by T sp,hot and T sp,cold, can be determined by conventional laws, called "water laws".

[0035] The term "water law" refers to a control function that establishes a relationship between the temperature of the heat pump and the outside temperature. The water law allows the heat pump to determine the setpoint temperature (Tsp,hot and Tsp,cold) for cooling or heating, given the outside temperature.

[0036] The setpoint values ​​for heating and cooling temperatures depend on consumer needs.

[0037] As a non-limiting example, the setpoint temperature for hot production T sp, hot can be greater than 30°C, in particular greater than 50°C.

[0038] For example, the setpoint temperature for cold production T sp, cold is less than 20°C, preferably less than 10°C, other values ​​being of course possible depending on the need.

[0039] Preferably, the hot buffer tank operates within a temperature range that includes, but is centered on, the hot production setpoint temperature Tsp,hot, and is, for example, between Tsp,hot - dT and Tsp,hot +dT. The parameter dT corresponds to a temperature hysteresis parameter in the hot buffer tank and can be between 0.1 °C and 10 °C, for example, approximately 2 °C. Alternatively, the hysteresis values ​​on either side of Tsp,hot are different.

[0040] Similarly, the buffer tank preferably operates within a temperature range centered on the setpoint temperature for cooling production, Tsp, cold, and for example, between Tsp, cold - dT' and Tsp, cold + dT'. The parameter dT' corresponds to a temperature hysteresis parameter in the cold buffer tank and can be between 0.1 °C and 10 °C, for example, approximately 2 °C. Alternatively, the hysteresis values ​​on either side of Tsp, cold are different.

[0041] Preferably, the comparison of a given value with the setpoint temperature for the production of cold or heat is carried out taking into account the temperature hysteresis in the corresponding buffer tank, as will appear later. Indicators

[0042] The implementation of the process according to the invention may involve the calculation of at least two Boolean indicators: A first indicator, called " hotprod", at least one state of which depends on information representing a future need for heat production, and a second indicator, called " coldprod ", at least one state of which depends on information representative of a future need for cold production.

[0043] The advantage of using Boolean indicators is to simplify the implementation of the invention, by facilitating its implementation on a controller controlling the operation of the heat pump.

[0044] Preferably, the first indicator hotprod takes a first boolean state at time t indicating a need to produce heat when: a) the temperature measured at time t in the hot buffer tank is less than the hot production setpoint temperature T sp, hot within the temperature hysteresis in said tank, in particular less than T sp, hot - dT, or b) the future temperature value(s) estimated in the hot buffer tank are less than the hot production setpoint temperature within the temperature hysteresis in said tank, in particular less than T sp, hot - dT.

[0045] Otherwise, that is, when neither of conditions a) and b) is met, the first indicator hotprod takes a second boolean state indicating the absence of a need for heat production.

[0046] We speak of a current need for heat production when condition a) is met.

[0047] We speak of a future need for heat production when condition b) is met.

[0048] Preferably, the second indicator coldprod takes a first boolean state at time t indicating a need to produce cold when: c) the temperature measured at time t in the cold buffer tank is greater than the setpoint temperature for cold production T sp, cold up to the temperature hysteresis in said tank, in particular greater than T sp, cold + dT', or d) the future temperature value(s) estimated in the cold buffer tank are greater than the setpoint temperature for cold production T sp, cold up to the temperature hysteresis in said tank, in particular greater than T sp, cold + dT'.

[0049] Otherwise, that is, when neither of conditions c) and d) is met, the second indicator coldprod takes a second boolean state indicating the absence of a need for cold production.

[0050] Similar to the first indicator hotprod,We can speak of a current need for cold production when condition c) is met.

[0051] Similarly, we can speak of a future need for cold production when condition d) is met.

[0052] Such indicators make it possible to estimate whether, while remaining within the operating ranges, i.e. respecting the temperature operating limits, it is preferable from an energy point of view to trigger a particular production mode when a decision based on a classic control method might not have done so. Triggering the modes

[0053] When the heat pump is previously stopped, the activation at time t of one of the three aforementioned operating modes can be controlled as follows: The first mode is preferably activated when the temperature measured at time t in the hot buffer tank is lower than the setpoint temperature for hot water production, within the temperature hysteresis of said tank, in particular lower than Tsp, hot - dT, and that the second indicator coldprod indicates the absence of a need, particularly current and / or future, for cold production.

[0054] The second mode is preferably triggered when the temperature measured at time t in the cold buffer tank is higher than the setpoint temperature for cold production, taking into account the temperature hysteresis in said tank, in particular Tsp, cold +dT', and that the first indicator hotprod indicates the absence of a need, particularly current and / or future, for heat production.

[0055] The third mode is preferably triggered when the indicators hotprod And coldprod indicate at the same time a need, in particular current and / or future, for the production of heat and cold, respectively.

[0056] When the heat pump operates according to one of the three aforementioned production modes, its operation may stop at a time t' when: the heat pump operates in the first mode of heat production only and the temperature measured at this time t' in the hot buffer tank is greater than T sp,hot + dT, the heat pump operates in the first mode of cold production only and the temperature measured at this time t' in the cold buffer tank is less than T sp,cold - dT', or the heat pump is in the first mode of simultaneous heat and cold production and the temperature measured at time t' in the hot buffer tank is greater than T sp, ,hot + dT or the temperature measured in the cold buffer tank is less than T sp ,cold - dT'.

[0057] Temperature measurements in the hot and cold buffer tanks are preferably carried out using respective sensors installed on these tanks. The sensors are preferably thermocouples.

[0058] The method according to the invention can be implemented on a physical controller, in particular a physical controller of a production system comprising the heat pump and buffer tanks. Such a controller includes, for example, a microcontroller, or any other component capable of performing the required functions.

[0059] The invention also relates to a heating and cooling production system, configured for implementing the process according to the invention, comprising: a heat pump capable of operating in at least one first mode of heat production only, a second of cold production only and a third of combined cold and heat production, at least two cold and hot buffer tanks connected to the heat pump, and a controller configured to control the triggering of the operating modes of the heat pump at a given time t as a function of the measured temperatures of the buffer tanks and at least one piece of information representative of a future need for heat or cold production for the buffer tanks.

[0060] Preferably, each buffer tank should include at least one temperature sensor.

[0061] Preferably, the system includes multiple valves, particularly three-way valves, positioned between the heat pump and the buffer tanks, as well as between the heat pump and a heat source. These valves allow for different hydraulic configurations depending on the production mode, through dynamic modification of the system's production flow.

[0062] The controller may include one or more processors and memory in which a set of instructions to be executed by the processor(s) is stored. The controller may be equipped with appropriate interfaces to control the elements of the heating and cooling system, including the system valves, and to receive temperature data from various sensors. Brief description of the drawings

[0063] The invention will be better understood upon reading the detailed description that follows, a non-limiting example of its implementation, and upon examination of the attached drawing in which: [ Fig 1 ] schematically and partially represents an example of a production system implementing a "thermo-refrigeration pump" type heat pump, [ Fig 2 ], [ Fig 3] and [Fig 4 ] illustrate the operation of the heat pump in heat-only production mode, cooling-only mode, and simultaneous production mode, respectively, [ Fig 5 ] illustrates the cumulative operating time according to the different production modes (in hours) of the heat pump with conventional control over one year, and [ Fig 6 ] is a view analogous to the figure 5 with a control method according to the invention. Detailed description

[0064] The method according to the invention makes it possible to control the operation of a heat pump, using indicators to indicate a future need for cooling or heating.

[0065] There figure 1 illustrates an example of a production system using a heat pump 10. This is known in itself, and includes a condenser and an evaporator.

[0066] In the illustrated example, the production system is a hot and cold water production system, including chilled water.

[0067] The hot water produced, for example, has a temperature above 40°C and can be used for domestic hot water and / or heating needs, or any other temperature required by the needs.

[0068] The cold water produced, particularly chilled water, has a temperature below 20°C, specifically below 10°C, or any other temperature required by the application. This cold water, especially chilled water, is used, for example, to meet air conditioning needs and / or for chilled water production, particularly in industrial processes or in hospitals.

[0069] As is known, the heat pump 10 is capable of simultaneously heating a hydraulic flow on an interface 12, at the passage between two terminals of the pump condenser, and cooling a second hydraulic flow on a second interface 14, at the passage between two terminals of the pump evaporator.

[0070] As illustrated in the figure 1A heat source 30 is connected to the heat pump via a hydraulic decoupling tank 32. The system further includes a hydraulic pump 34 downstream of the heat source 30 and upstream of the hydraulic tank 32 and a three-way valve 34 disposed between the hydraulic tank 32 and the heat pump 34. In this example, the heat source is a geothermal field, but other sources, such as an aquifer, a lake or an energy loop, can be used.

[0071] The system also includes auxiliary cooling units 62 and heating units 65. These auxiliary units are optional, but typical of such installations to ensure redundancy in case of a malfunction of the main production system. In the example shown, the auxiliary units 62 and 64 correspond to a chiller and a gas boiler, respectively.

[0072] The system also includes two buffer tanks 22 and 24, corresponding to hydraulic storage volumes, respectively hot and cold, each including at least one temperature sensor 82 or 84, for example with a thermocouple.

[0073] The buffer tanks 22 and 24 are respectively connected to the heat pump via three-way valves 23 and 25. These are also connected to the heat source 30.

[0074] The buffer tank 22 is also connected to the heat pump 10 by a pipe 27 ensuring the return of water from said tank to the heat pump 10, passing through a hydraulic pump 26.

[0075] Similarly, the buffer tank 24 is further connected to the heat pump 10 by means of a pipe 29 ensuring the return of the water from said tank 24 to the heat pump 10, passing through a hydraulic pump 28.

[0076] In the illustrated example, the hot buffer tank operates within a temperature range centered on a hot production setpoint temperature T sp, hot, and between T sp, hot - dT and T sp, hot +dT.

[0077] Similarly, the buffer tank preferably operates within a temperature range centered on the cold production setpoint temperature T sp, cold, and between T sp, cold -dT and T sp, cold +dT.

[0078] The setpoint temperatures are usually determined by classical water temperature laws. The parameter dT corresponds to a temperature hysteresis parameter in buffer tanks and can be between 0.1 °C and 10 °C, for example approximately 2 °C.

[0079] The contents of buffer tanks 22 and 24 are used to transfer thermal power through heat exchangers to secondary circuits 41 and 43, which supply the end users. The use of buffer tanks adds thermal inertia to the production circuits and prevents short-cycling of the heat pump.

[0080] As mentioned previously, the heat pump 10 is capable of operating in at least one first mode of heat production only, a second mode of cold production only and a third mode of combined cold and heat production.

[0081] There figure 2This illustrates the hydraulic connections when the heat pump is operating in heating-only mode. Arrows 51 and 53 represent the useful flows: Arrow 53 indicates the hydraulic circulation in contact with interface 14 of the heat pump. Arrow 51 indicates the hydraulic circulation in contact with interface 12 of the heat pump. The user demands for heating and cooling are shown on the right. In this operating mode, the cooling energy is discharged to the heat source 30.

[0082] There figure 3 This illustrates the hydraulic connections in the case of the heat pump operating in cooling-only mode. In this production mode, the heat energy is transferred to the heat source 30.

[0083] There figure 4illustrates the hydraulic connections in the case of the heat pump operating in simultaneous production mode. In this case, the heat source 30 is momentarily disconnected from the production system.

[0084] To control the activation of the aforementioned modes, the system also includes a controller 70. This controller manages the three-way valves of the production system. These valves operate in an on / off mode and are synchronized to activate one or the other of the desired modes.

[0085] The controller is configured to determine requirements using thermocouple sensors from buffer tanks, setpoint temperatures, and demand prediction indicators, as will be detailed below.

[0086] The triggering of an operating mode by the control unit at a given time ti preferably involves boolean indicators hotprodAnd coldprod at least one of whose respective states provides information on a need for the production of heat and cold.

[0087] These Boolean indicators are obtained respectively by estimating a time function representing the evolution over time of the temperature in the hot buffer tank and the cold buffer tank.

[0088] In the illustrated example, each time function is an affine function. f(T)=at+b, Or T denotes the temperature at the moment t. Each affine function f(T) is calculated by linear regression from the values ​​of the temperature of the corresponding balloon, observed over a past horizon including the time ti [ti- Δt past , ti ].

[0089] Once the time functions are calculated, they are used to estimate one or more future temperature values ​​in the buffer tanks over a future horizon [ti, ti + Δt future]. For example, Δt past = Δt future = 15 min. From the temperature values ​​thus estimated, the hotprod and coldprod indicators are preferably calculated as follows: Indicator hotprod The indicator hotprodtakes a first Boolean state, designated by "TRUE" or "1" indicating a need for heat production, if one of the following two propositions is true: ∘ the measured temperature in the hot tank is below the difference T sp,hot - dT between the heat production setpoint temperature T sp,hot and the parameter dT of the temperature hysteresis in the hot buffer tank 22, or ∘ the estimated future value(s) for the temperature in the hot buffer tank 22 over the future horizon are below the difference T sp,hot - dT between the heat production setpoint temperature T sp,hot and the parameter dT of the temperature hysteresis in the hot buffer tank 22; otherwise hotprod takes a second boolean state, designated by "FALSE" or "0", the second boolean state indicating the absence of a need for heat production. Indicator coldprod The indicator coldprodtakes a first Boolean state, designated by "TRUE" or "1", if one of the following two propositions is true: • the measured temperature in the cold buffer tank 24 is greater than the sum T sp,cold + dT of the cooling production setpoint temperature T sp,cold and the parameter dT of the temperature hysteresis in the cold buffer tank 24; • the estimated future value(s) for the temperature in the cold buffer tank over the future horizon are greater than the sum T sp,cold + dT of the cooling production setpoint temperature T sp,cold and the parameter dT of the temperature hysteresis in the cold buffer tank 24; Otherwise, coldprod takes a second boolean state, designated by "FALSE" or "0", this second state indicating the absence of a need for cold production.

[0090] At time ti, the operation of the heat pump 10 when it is stopped is as follows: When the temperature measured at time ti in the hot buffer tank is less than Tsp, hot - dT and the indicator coldprod returns the boolean state FALSE or 0, that is to say indicates the absence of need, especially current and / or future, for cold production, then the first mode of heat production only is triggered.

[0091] When the temperature measured at time ti in the cold buffer tank 24 is greater than Tsp, cold + dT and the indicator hotprod returns the boolean state FALSE or 0, in other words indicates the absence of need, especially current and / or future, for heat production, so the second mode of cold production is triggered.

[0092] When each of the indicators hotprod And coldprodreturns the boolean state TRUE or 1, that is to say indicate respectively a need, in particular current and / or future, for the production of heat and cold, then the third mode of simultaneous production of heat and cold is triggered.

[0093] When the heat pump is in operation, it can stop at a time t' for a minimum duration of δt seconds if it is in first production mode and the temperature measured at this instant t' in the hot buffer tank is greater than T sp,hot + dT, it is in second production mode and the temperature measured at this instant t' in the cold buffer tank is less than T sp,cold - dT, or it is in third production mode and the temperature measured in the hot buffer tank at time t' is greater than T sp,hot + dT or the temperature measured in the cold buffer tank is less than T sp,cold - dT. Comparative example

[0094] The process according to the invention was implemented on a digital model representative of a hot and cold water production system, involving the heat pump 10 connected to the geothermal field 30.

[0095] THE Figures 5 And 6 illustrate the cumulative operating time in hours of the heat pump when applying conventional control and control using the control method according to the invention, respectively. Curves a, b, and c correspond to the operating times according to the first mode of heat production only, the second mode of cooling production only, and the third mode of simultaneous heating and cooling production, respectively. A) Control by conventional control

[0096] The conventional control system used for the heat pump / refrigerator is as follows: First method of heat production

[0097] The first mode of heat-only production is triggered at time t if: The heat pump is currently stopped, the measured temperature of the hot buffer tank is less than Tsp, hot - dT. The temperature of the cold buffer tank is less than Tsp, cold + dT. Second method of cold production

[0098] The second mode of cold production alone is triggered if: the heat pump is currently stopped, the measured temperature of the hot buffer tank is greater than T sp, hot - dT, the temperature of the cold buffer tank is greater than T sp, cold + dT. Third method of simultaneous production of heat and cold

[0099] The third method of simultaneous production of cold and heat, if: the heat pump is currently stopped, the measured temperature of the hot buffer tank is less than T sp, hot - dT, the temperature of the cold buffer tank is greater than T sp, cold + dT.

[0100] When the heat pump is operating in one of the three modes above, it will shut down for a minimum duration of δt seconds when: The heat pump is in first production mode and the measured temperature of the hot buffer tank is greater than Tsp,hot + dT; the heat pump is in second production mode and the measured temperature of the chilled water buffer tank is less than Tsp,cold - dT; the heat pump is in third production mode and: ▪ Either the measured temperature of the cold buffer tank is less than T sp , cold − dT ▪ Either the measured temperature of the hot buffer tank is greater than T sp , hot + dT . B) Control using the method according to the invention

[0101] The control of the heat pump according to the invention is as follows: First method of heat production

[0102] The first mode of heat-only production is triggered at time t if: the heat pump is currently stopped, the measured temperature of the hot buffer tank is less than T sp, hot - dT, and the COLDPROD indicator returns the boolean FALSE. Second method of cold production

[0103] The second mode of cold production alone is triggered if: the heat pump is currently stopped, the HOTPROD indicator returns the boolean FALSE, and the temperature of the cold buffer tank is greater than the setpoint T, cold + dT. Third method of simultaneous production of heat and cold

[0104] The third method of simultaneous production of cold and heat, if: The heat pump is currently stopped, the HOTPROD indicator returns the boolean TRUE, and the COLDPROD indicator returns the boolean TRUE.

[0105] When the heat pump is operating in one of the three modes above, it shuts down for a minimum duration of δt seconds when The heat pump is in first production mode and the measured temperature of the hot buffer tank is greater than Tsp,hot + dT; the heat pump is in second production mode and the measured temperature of the chilled water buffer tank is less than Tsp,cold - dT; the heat pump is in third production mode and: ▪ Either the measured temperature of the cold buffer tank is less than T sp , cold − dT , ▪ Either the measured temperature of the hot buffer tank is greater than T sp , hot + dT .

[0106] For both control methods, the value of the hysteresis parameter dT used is 2°C.

[0107] THE Figures 5 And 6These indicators provide macroscopic insights into the system's annual operation, including the usage times of each production mode throughout the year. It is observed that the use of the third simultaneous production mode increases significantly when the operation of the heat pump 10 is controlled according to the method of the invention. For example, the usage time of this third mode increases from 82 hours for conventional control to 436 hours when the method of the invention is implemented, representing an increase of approximately 430%. The method of the invention therefore favors the third production mode at the expense of the other production modes.

[0108] Taking the example of the French economic context in 2020 for electricity and gas prices, an operational gain of 5% can be achieved when the process according to the invention is implemented. Furthermore, the operating time of the heat pump 10 is reduced by approximately 300 hours per year without increasing the number of start-ups required, thus delaying its aging.

[0109] The comparative example just described quantitatively demonstrates that the process according to the invention, by favoring the 'thermo-refrigeration-pump' production mode by default over other operating modes, allows for significant gains in system operation. While the implementation of the estimators is as simple as possible in the illustrated example, the gains are substantial.

[0110] The invention is not limited to the example just described. For example, the time function can be estimated by means other than linear regression.

Claims

1. Method for controlling the operation of a thermo-refrigeration pump (10) connected to hot (22) and cold (24) buffer tanks, which is capable of operating according to at least a first mode for production of heat alone, a second for production of cold alone and a third for combined production of cold and heat, the various modes being triggered at a given instant t as a function of the measured temperatures of the buffer tanks and of at least one item of information representative of a future need for production of heat or cold for the buffer tanks.

2. Control method according to Claim 1, the future need for production of heat or cold being predicted by estimating at least one future value of the temperature in the corresponding buffer tank (22; 24) and by comparing the one or more estimated values with at least one setpoint temperature for production of heat or cold.

3. Control method according to Claim 1 or 2, the future need for production of heat or cold being estimated from the past observation of the temperature in the corresponding buffer tank.

4. Control method according to the preceding claim, the future need for heat or cold being estimated by: - determining a time function representative of the evolution over time of the temperature in the corresponding buffer tank on the basis of the past observation of the temperature in said tank, - estimating at least one future value of the temperature in the corresponding buffer tank over a future time horizon from the time function, and - comparing the one or more temperature values thus estimated with at least one setpoint temperature for production of heat or cold.

5. Control method according to Claim 4, the time function being determined by a regression method on the past observation, the time function preferably being a polynomial function of degree greater than or equal to 1, preferably of degree equal to 1.

6. Control method according to either of Claims 4 and 5, the future time horizon being between 5 min and 3 h, better still between 5 min and 1 h, even better still between 10 min and 30 min.

7. Method according to one of Claims 3 to 6, the past observation being effected over a past time horizon of between 5 min and 3 h, better still between 5 min and 1 h, even better still between 10 min and 30 min, the past horizon preferably containing said given instant t.

8. Control method according to any one of Claims 2 to 7, involving the calculation of a first Boolean indicator, called "hotprod", of which at least one state depends at least on the item of information representative of a future need to produce heat, and of a second Boolean indicator, called "coldprod", of which at least one state depends at least on the item of information representative of a future need to produce cold.

9. Control method according to the preceding claim, the first indicator hotprod taking, at the instant t, a first Boolean state indicating a need to produce heat when: a) the temperature measured at the instant t in the hot buffer tank is lower than the setpoint temperature for production of heat, to within a temperature hysteresis in the hot buffer tank, or b) the one or more estimated future values of the temperature in the hot buffer tank are lower than the setpoint temperature for production of heat, to within said hysteresis, the first indicator otherwise, i.e. when neither of the conditions a) and b) are met, taking a second Boolean state indicating the absence of need for production of heat.

10. Control method according to Claim 8 or 9, the second indicator coldprod taking, at the instant t, a first Boolean state indicating a need to produce cold when: c) the temperature measured at the instant t in the cold tank is higher than the setpoint temperature for production of cold, to within a temperature hysteresis in said buffer tank, d) the one or more estimated values of the temperatures in the cold buffer tank are higher than the setpoint temperature for production of cold, to within said hysteresis, the second indicator otherwise, i.e. when neither of the conditions c) and d) are met, taking a second Boolean state indicating the absence of need for production of cold.

11. Control method according to any one of Claims 8 to 10, the thermo-refrigeration pump being stopped beforehand; the first mode being triggered when the temperature measured at the instant t in the hot buffer tank (22) is lower than the setpoint temperature for production of heat, to within the temperature hysteresis in said tank, and when the second indicator coldprod indicates the absence of need for production of cold.

12. Method according to one of Claims 8 to 11, the thermo-refrigeration pump being stopped beforehand, the second mode being triggered when the temperature measured at the instant t in the cold buffer tank (24) is higher than the setpoint temperature for production of cold, to within the temperature hysteresis in said tank, and when the first indicator hotprod indicates the absence of need for production of heat.

13. Method according to any one of Claims 8 to 12, the thermo-refrigeration pump being stopped beforehand, the third mode being triggered when the indicators hotprod and coldprod indicate a need for production of heat and cold, respectively, at the same time.

14. System for production of heat and cold, configured to implement the method according to any one of the preceding claims, having: - A thermo-refrigeration pump (10) capable of operating according to at least a first mode for production of heat alone, a second for production of cold alone and a third for combined production of cold and heat, - At least two cold and hot buffer tanks (22; 24) connected to the thermo-refrigeration pump (10), and - a controller (70) configured to control the triggering of the modes of operation of the thermo-refrigeration pump at a given instant t as a function of the measured temperatures of the buffer tanks and of at least one item of information representative of a future need for production of heat or cold for the buffer tanks.