Method, controller and system for controlling the thermal power transfer through a thermal energy exchanger

Abstract

A method of controlling heat power transfer of a thermal energy exchanger (80) of an HVAC system (1), the method comprising: receiving, by a controller (10), a setpoint heat power transfer (Power SP); measuring, by a flow sensor (52), a measured flow of a fluid (Φ act ) through the thermal energy exchanger (80); determining, by the controller (10), an estimated heat power transfer (Power EST) using the measured flow of the fluid (Φ act ) and a defined flow rate to delta T mapping; comparing, by the controller (10), the setpoint heat power transfer (Power SP) and the estimated heat power transfer (Power EST); and adjusting, by the controller (10), the flow of the fluid (Φ act ) through the thermal energy exchanger (80) based on the comparison.

Description

Technical Field

[0001] This invention relates to a method for controlling the heat power transfer of a heat exchanger in a heating, ventilation, and air conditioning (HVAC) system. The invention also relates to a controller for controlling the heat power transfer of a heat exchanger in an HVAC system. Furthermore, the invention relates to a computer program product comprising instructions that, when executed by a processor of the controller, control the heat power transfer of the heat exchanger in the HVAC system. Background Technology

[0002] By adjusting the flow rate of fluid through the heat exchanger of an HVAC system, it is possible to adjust the amount of energy transferred by the heat exchanger (correspondingly, the amount of energy per unit time, or power). For example, energy exchange or power transfer can be adjusted by regulating the amount of energy delivered by the heat exchanger for heating or cooling rooms in a building, or by regulating the amount of energy extracted by the chiller for cooling purposes. Although fluid transport through the fluid loops of an HVAC system is driven by one or more pumps or fans, the flow rate is typically adjusted, for example, manually or by changing the orifice (opening) or position of a valve using an actuator.

[0003] The actual power transfer characteristics of heat exchangers in HVAC systems depend on various environmental conditions such as temperature and humidity. Under steady / static conditions, the power transfer calculation Q≈Φ·ΔT is sufficiently accurate for controlling power transfer. However, in HVAC systems with numerous transient events and processes (such as frequently changing flow rates and temperature differences ΔT), this basic power transfer calculation Q≈Φ·ΔT alone is often insufficient for accurate power transfer control.

[0004] Based on known methods and corresponding control systems for controlling energy transfer in heat exchangers of HVAC systems with numerous transient events and processes, a flow sensor measures the flow rate of fluid through the heat exchanger, a first temperature sensor measures the supply temperature of the heat exchanger, and a second temperature sensor measures the return temperature from the heat exchanger. The control system uses one or more measurement datasets to determine flow-dependent model parameters for modeling the performance of the heat exchanger, where each measurement dataset includes values ​​for the measured flow rate, the measured supply temperature, and the measured return temperature of the fluid at a corresponding measurement time. Using the flow-dependent model parameters, the control system calculates an estimated energy transfer to the heat exchanger and uses this estimated energy transfer to control the energy transfer of the heat exchanger by adjusting the flow rate of the fluid through it.

[0005] However, this solution requires several sensors to measure environmental variables, particularly a temperature sensor for measuring the supply temperature to the heat exchanger and a second temperature sensor for measuring the return temperature from the heat exchanger. Summary of the Invention

[0006] The object of the present invention is to provide a method and control system for controlling the power transfer of a heat exchanger in an HVAC system, which does not have at least some of the disadvantages of the prior art.

[0007] In particular, the object of the present invention is to provide a method and control system for controlling the power transfer of a heat exchanger in an HVAC system under dynamic environmental conditions while reducing the need for sensors.

[0008] According to the present invention, these objectives are addressed by a method for controlling the heat power transfer of a heat exchanger in an HVAC system. In a first step of the method according to the invention, a controller receives the setpoint heat power transfer. In a further subsequent or simultaneous step, a flow sensor measures the flow rate of fluid through the heat exchanger at the current position of a valve in the HVAC system arranged to regulate the flow rate of fluid through the heat exchanger. Using the measured fluid flow rate, the controller determines an estimated heat power transfer based on a defined flow rate to ΔT mapping.

[0009] Specifically, the flow rate to ΔT mapping is defined as the relationship between the flow rate of the fluid through the heat exchanger and the temperature difference across the heat exchanger. According to embodiments of this disclosure, the flow rate to ΔT mapping is defined based on calculations and / or mathematical models and / or measurements of the temperature difference and flow rate across the heat exchanger. According to embodiments of this disclosure, the flow rate to ΔT mapping is calibrated and / or iteratively refined based on measurements of the temperature difference and flow rate across the heat exchanger of an HVAC system or other HVAC systems.

[0010] After determining the estimated heat power transfer, the controller compares the setpoint heat power transfer with the estimated heat power transfer.

[0011] Subsequently, the controller controls the flow rate of fluid through the heat exchanger based on comparison (in particular by generating control signals based on comparison), thereby controlling the heat power transfer of the heat exchanger.

[0012] According to a first embodiment of this disclosure, the controller regulates the flow rate of fluid through a heat exchanger by generating valve control signals for controlling the orifices of valves in an HVAC system. Valves are arranged in the flow path between the heat exchanger and an energy source, such as a heating device (furnace, heat pump) or a cooling device (refrigeration unit), to regulate the flow rate of fluid to and / or from the heat exchanger. Specifically, valves are arranged in a fluid transport system for moving (heat transfer) fluids (e.g., liquids (e.g., water and / or refrigerant) or gases (e.g., air)) to and from the heat exchanger. The fluid transport system may include fluid transport lines (pipes or conduits) for guiding fluid flow through the heat exchanger.

[0013] According to another embodiment of this disclosure, the controller regulates the flow rate of fluid through a heat exchanger by generating a pressure control signal for controlling the supply pressure of the fluid. Specifically, the fluid supply pressure is provided by a pump or fan to drive and control the flow of fluid through the heat exchanger. Accordingly, a pressure control signal is generated to control the pump or fan to drive and control the flow of fluid through the heat exchanger. According to embodiments of this disclosure, the pump or fan is included in or connected to an HVAC system.

[0014] According to the embodiments disclosed herein, the controller controls the heat power transfer by generating control signals (valve control signals and / or pressure control signals) based on comparison, so as to minimize the difference between the setpoint heat power transfer and the estimated heat power transfer.

[0015] According to embodiments of this disclosure, the mapping from flow rate to ΔT is defined based on one or more of the following:

[0016] - The heat transfer characteristic curve of the heat exchanger, wherein the heat transfer characteristic curve indicates the amount of heat energy transferred by the heat exchanger as a function of the flow rate of the fluid passing through the heat exchanger.

[0017] - The heat transfer coefficient of a heat exchanger, wherein the heat transfer coefficient of a heat exchanger is a ratio (e.g., W / (m2*K)) between the heat flux (e.g., W / (m2*K)) and the thermodynamic driving force for the heat flow that is a characteristic of the heat exchanger.

[0018] - The thermal conductivity of a heat exchanger, which is a measure of the heat exchanger's ability to conduct heat.

[0019] - The flow rate and / or temperature of the secondary fluid (e.g., air) passing through the heat exchanger and / or surrounding the heat exchanger. Specifically, according to embodiments of this disclosure wherein the heat exchanger is arranged in an air duct, the air flow rate relates to the flow rate of air passing through the air duct in which the heat exchanger is arranged. According to embodiments of this disclosure, the air flow rate is influenced by a fan constructed and arranged to drive air through the heat exchanger.

[0020] - The convective heat transfer coefficient of a fluid, which is a measure of the fluid’s ability to transfer heat by conduction and is a characteristic of a particular fluid, particularly as the sum of the fluid’s ability to transfer heat through a combination of conduction (thermal diffusion) and convection (heat transfer through the overall fluid flow).

[0021] - The current operating mode of the heat exchanger, wherein the operating mode of the heat exchanger includes (but is not limited to) a cooling operating mode and a heating operating mode. In particular, the mapping of flow rate to ΔT is defined based on the values ​​of characteristics that are specific operating modes of the heat exchanger.

[0022] - Heat exchanger type, including (but not limited to) water / water, water / air, or air / air type heat exchangers. In particular, the flow rate to ΔT mapping is defined based on empirical values ​​that are characteristics of a particular type of heat exchanger.

[0023] - Geometric data of the heat exchanger, such as the heat exchange surface. In particular, the mapping of flow rate to ΔT is limited by a value corresponding to the geometry (dimensions) of the heat exchanger / calculated based on the geometry (dimensions) of the heat exchanger.

[0024] According to embodiments of this disclosure, as part of determining the estimated heat power transfer, the controller determines the estimated temperature difference on the heat exchanger based on the measured flow rate of the fluid, wherein the controller determines the estimated heat power transfer based on the measured flow rate of the fluid and the estimated temperature difference.

[0025] According to embodiments of this disclosure, the temperature of the secondary fluid passing through and / or surrounding the heat exchanger is measured by a temperature sensor. Alternatively, data indicating the temperature of the secondary fluid is received by a controller (from a data source / sensor external to the HVAC system). The flow rate to ΔT mapping is defined and / or calibrated using the temperature of the secondary fluid.

[0026] For example, in the cooling operation mode of a heat exchanger, for an assumed constant supply temperature of the fluid (e.g., 6°C), the mapping of flow rate to ΔT is determined using extrapolation based on the following (empirical data):

[0027] - The known temperature difference of 6°K at maximum fluid flow rate;

[0028] - A known temperature difference that is substantially the same as the temperature of the secondary fluid (air) at a sufficiently low fluid flow rate.

[0029] Therefore, heat transfer can be accurately estimated even without the need for a temperature sensor to measure the fluid's supply or return temperature. According to embodiments of this disclosure, the fluid's supply or return temperature is measured by a temperature sensor. Alternatively, data indicating the fluid's supply or return temperature is received by a controller (from a data source / sensor external to the HVAC system). The flow rate to ΔT mapping is then calibrated using the fluid's supply or return temperature.

[0030] In order to control the orifice of the valve and thereby control the flow rate of fluid through the heat exchanger, embodiments of the present invention further include the following steps: transmitting a valve control signal by a controller to an actuator mechanically coupled to the valve; and actuating the valve by the actuator according to the valve control signal.

[0031] In order to control the supply pressure and thereby control the flow rate of fluid through the heat exchanger, embodiments of the present invention further include the steps of: transmitting a pressure control signal by a controller to a device (such as a pump or fan) for driving and controlling the flow of fluid; and controlling the pump or fan according to the pressure control signal.

[0032] According to the present invention, the objective identified above is further addressed by a controller for controlling the heat power transfer of a heat exchanger, the controller comprising a processor configured to perform a method according to one of the embodiments disclosed herein.

[0033] According to the present invention, an HVAC system further addresses the objectives identified above, the HVAC system comprising: a heat exchanger; a controller communicatively connected to an actuator; and a flow sensor configured to measure the flow rate of fluid passing through the heat exchanger. The controller is configured to: determine an estimated heat power transfer using the measured fluid flow rate and a defined flow rate-to-ΔT mapping; and generate a control signal for regulating the flow rate of fluid passing through the heat exchanger based on the comparison.

[0034] According to embodiments of this disclosure, the HVAC system (1) further includes a valve (40) having an orifice and an actuator (20) mechanically coupled to the valve (40). Control signals generated by the controller (10) include valve control signals for controlling the orifice of the valve (40) of the HVAC system (1). The controller (10) is also configured to transmit the valve control signals to the actuator (20), which is configured to actuate the valve controlling the orifice to regulate the flow rate of fluid through the heat exchanger according to the valve control signals.

[0035] According to another embodiment of this disclosure, the HVAC system also includes a pump (100) for driving fluid (W) through a heat exchanger (90). Accordingly, the control signal generated by the controller (10) includes a pressure control signal for controlling the supply pressure of the fluid (W). The controller (10) is also configured to transmit the pressure control signal to the pump (90), which is configured to drive fluid (W) through the heat exchanger (80) at the supply pressure according to the pressure control signal.

[0036] Known specific applications of HVAC systems include two- or three-way flow regulators arranged in the flow path of a heat exchanger and one or more fluid sources, which allow the flow rate of fluid to be regulated by actuation between an open position and a closed position.

[0037] Another known specific application of HVAC systems includes a 6-way flow regulator arranged between a heat exchanger and fluid sources at a first temperature and a second temperature. Specifically, the 6-way flow regulator is used in applications where the same heat exchanger is used for both heating and cooling, and is arranged to switch the fluid input and return of the heat exchanger between a first fluid loop and a corresponding second fluid loop. The 6-way flow regulator includes: a first fluid input; a second fluid input; a fluid output; a fluid return input; a first fluid return output; and a second fluid return output. The known 6-way flow regulator can operate in a first operating mode, a second operating mode, and a third operating mode. In the first operating mode, the 6-way flow regulator allows fluid to flow from the first fluid input towards the fluid output and from the fluid return input towards the first fluid return output. In the second operating mode, the 6-way flow regulator allows fluid to flow from the second fluid input towards the fluid output and from the fluid return input towards the second fluid return output. In the third operating mode, the 6-way flow regulator prevents fluid from passing between any of the following: the first fluid input; the second fluid input; the fluid output; the fluid return input; the first fluid return output; and the second fluid return output.

[0038] Another embodiment of the present invention aims to enable an HVAC system including six flow regulators to operate according to environmental conditions while avoiding at least some of the drawbacks associated with known solutions. According to embodiments of this disclosure, this additional objective is achieved by an HVAC system having six flow regulators, wherein actuators are configured to control the six flow regulators in a first operating mode and a second operating mode based on valve control signals. In the first operating mode, controlling the orifices of the six flow regulators enables: regulating the flow rate of fluid from a first fluid input to a fluid output; and regulating the flow rate of fluid from a fluid return input to a first fluid return output. In the second operating mode, controlling the orifices of the six flow regulators enables: regulating the flow rate of fluid from a second fluid input to a fluid output; and regulating the flow rate of fluid from a fluid return input to a second fluid return output.

[0039] According to the present invention, the objectives identified above are further addressed by a computer program product comprising instructions that, when executed by a processor of a controller for an HVAC system including a heat exchanger and a flow sensor, cause the HVAC system to perform a method for controlling the heat power transfer of the heat exchanger according to one of the embodiments disclosed herein.

[0040] It should be understood that both the foregoing general description and the following detailed description present embodiments and are intended to provide an overview or framework for understanding the nature and features of this disclosure. The accompanying drawings are included to provide further understanding and are incorporated into and form a part of this specification. The drawings illustrate various embodiments and, together with the description, serve to explain the principles and operation of the disclosed concepts. Attached Figure Description

[0041] The disclosure described herein will be more fully understood from the detailed description and accompanying drawings given below, and the drawings should not be considered as limiting the disclosure described in the appended claims. The drawings are shown below:

[0042] Figure 1 Illustrative heat power transfer characteristic curves of a common heat exchanger are shown;

[0043] Figure 2 An illustrative flow rate to ΔT mapping curve is shown superimposed on the corresponding heat power transfer characteristic curve of a conventional heat exchanger;

[0044] Figure 3 A scatter plot is shown, illustrating the relationship between heat power transfer and fluid flow rate under various operating conditions of the heat exchanger;

[0045] Figure 4A scatter plot is shown, illustrating an example of the flow rate to ΔT mapping, representing the relationship between ΔT and fluid flow rate for various operating conditions of a heat exchanger;

[0046] Figure 5A A highly schematic block diagram of an embodiment of an HVAC system according to the present invention is shown;

[0047] Figure 5B A highly schematic block diagram of another embodiment of the HVAC system according to the present invention is shown;

[0048] Figure 6 A schematic block diagram of the controller according to the present invention is shown;

[0049] Figure 7 A schematic block diagram of the height of the sensor module according to the present invention is shown;

[0050] Figure 8 A schematic block diagram of the actuator of an HVAC system according to this disclosure is shown.

[0051] Figure 9 An illustrative view of a controller connected to an actuator according to the invention is shown, the actuator being mechanically coupled to a valve;

[0052] Figure 10 An illustrative view of a controller according to the invention is shown, which is mechanically coupled to a valve including a 6-way flow regulator.

[0053] Figure 11 A simplified flowchart of a first embodiment of a method for controlling the orifice of a valve in an HVAC system according to the present invention is shown;

[0054] Figure 12 A simplified flowchart of another embodiment of the method for controlling the orifice of a valve in an HVAC system according to the present invention is shown;

[0055] Figure 13 A simplified flowchart illustrating another embodiment of the method for controlling the orifice of a valve in an HVAC system according to the present invention is shown; and

[0056] Figure 14 A simplified flowchart of another embodiment of the method for controlling the orifice of a valve in an HVAC system according to the present invention is shown. Detailed Implementation

[0057] Reference will now be made in detail to certain embodiments, examples of which are illustrated in the accompanying drawings, which show some, but not all, of the features. In fact, the embodiments disclosed herein can be implemented in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Wherever possible, the same reference numerals will be used to refer to the same parts or components.

[0058] Figure 1 Illustrative heat power transfer characteristic curves of a typical heat exchanger are shown, illustrating the relationship between heat power transfer Q and fluid flow rate Φ under specific operating conditions. Measured heat transfer is shown on the y-axis, and flow rate is shown on the x-axis.

[0059] It can be seen that increasing the flow rate Φ increases heat power transfer. However, this behavior is non-linear. As the flow rate Φ continues to increase, the corresponding increase in heat power transfer Q steadily decreases. In fact, a leveling-off can be observed, such that at high flow rates Φ, further increasing the flow rate Φ results in only a small increase in heat power transfer Q. Once this leveling-off occurs, the heat exchanger 80 is said to be operating at saturation. Saturation occurs when the heat exchanger 80 has reached a state where further increasing the flow rate Φ does not result in a significantly larger heat power transfer Q. Depending on the embodiment, the point at which saturation occurs is defined differently. For example, the saturation point SAT can be calculated as the percentage of heat power transferred by the heat exchanger 80 at the maximum flow rate Φ.

[0060] Figure 2 It shows the superimposed on Figure 1 The illustrative flow rate to ΔT mapping curve (shown as a dashed line) is shown on the corresponding heat power transfer characteristic curve of a typical heat exchanger. As can be seen, when the heat power transfer Q begins to level off at higher flow rates Φ (when heat exchanger 80 approaches saturation—shown as the gray band on the X-axis), the temperature difference ΔT on heat exchanger 80 decreases and eventually approaches level off.

[0061] Figure 3 Scatter plots are shown illustrating various relationships between heat transfer on the y-axis and water flow rate (measured in kg / s) on the x-axis for heat exchanger 80, and their various operating conditions. Specifically, for multiple operating conditions of heat exchanger 80, the heat power transfer Q from fluid W (specifically, water) through heat exchanger 80 to secondary fluid A (specifically, air) is shown as a function of the current flow rate Φ (specifically, water flow rate). Each point on the scatter plot represents the heat power transfer Q of heat exchanger 80 under a specific operating condition and water flow rate Φ. The mean curve MC shows the average response.

[0062] For illustrative purposes, Figure 3In the scatter plot, the saturation point SAT is defined as 85% of the maximum heat power transferred for the average heat exchanger 80, which has a response curve defined by the mean curve MC (shown as a dashed line). It can also be seen that by extending a line through the origin and the saturation point SAT located on the mean curve MC, the points in the top scatter plot are divided into two regions, corresponding to unrestricted flow marked as black dots and restricted flow marked as gray dots. The saturation point SAT defines both the heat power transfer Q and the corresponding water flow rate Φ required for the heat exchanger 80 of HVAC system 1 to achieve such heat power transfer Q, located on the mean curve MC. This saturation point SAT can be used to control any heat exchanger 80 of HVAC system 1.

[0063] Figure 4 A scatter plot is shown, illustrating an example of the flow rate to ΔT mapping, representing the relationship between ΔT and fluid flow rate for various operating conditions of the heat exchanger 80. Figure 4 The scatter plot is similar to Figure 3 The scatter plot is valuable because it shows multiple measurement points of the heat exchanger 80 of the HVAC system 1 operating under different operating conditions and flow rates W. However, in Figure 4 In the scatter plot, ΔT is plotted in Kelvin against the flow rate W in kg / s, where ΔT is the current supply temperature T of the fluid W. IN and the current return temperature T of fluid W out The difference between them. At a low flow rate W, the fluid moves slowly enough through the heat exchanger 80 so that the current supply temperature T remains constant. IN and the current return temperature T out The difference is large because there is sufficient time for heat to be transferred from the fluid W moving through the heat exchanger 80. Figure 4As can be seen in the scatter plot, ΔT decreases as the flow rate W increases. This is because the fluid W resides in the heat exchanger 80 for a shorter time, allowing less heat to flow. This relationship is non-linear, making the corresponding decrease in ΔT smaller and smaller for a constant increase in the flow rate W. The mean curve MC, representing the average relationship between ΔT and the flow rate, is also plotted on the bottom scatter plot. Therefore, the saturation point SAT of the bottom scatter plot can also be defined as the minimum value of ΔT (which also defines the maximum flow rate), below which the heat exchanger 80 operates inefficiently. By using this definition of ΔT with a value of, for example, 10 Kelvin, a given heat exchanger 80 can be controlled so that ΔT does not fall below the defined saturation point SAT. However, it can be seen that for the various operating conditions of the heat exchanger 80 plotted on the bottom scatter plot, under some operating conditions, a relatively small flow rate Φ is required to achieve the minimum ΔT, while under other operating conditions, a very high flow rate is required to achieve the same minimum ΔT as defined by the saturation point SAT. In the former case, the heat exchanger 80 operates efficiently, while in the latter case, the heat exchanger 80 no longer operates efficiently.

[0064] Generally, by operating the heat exchanger 80 above the saturation point SAT, little or no additional heat can be transferred. The additional energy required by the pump to drive the fluid through the pipes and heat exchanger 80 results in a decrease in the overall efficiency of the HVAC system 1.

[0065] Now go to Figure 5A The HVAC system 1 according to a first embodiment of the present invention will be described with reference to its highly schematic block diagram. As illustrated, the HVAC system 1 includes: a heat exchanger 80; a valve 40 having an orifice; an actuator 20 mechanically coupled to the valve 40; a controller 10 communicatively connected to the actuator 20; and a sensor module 50 including a flow sensor 52 configured to measure the flow rate Φ of fluid passing through the heat exchanger 80 at the current position of the valve 40. act .

[0066] The controller 10 will be shown below with reference to its structure. Figure 6 and about its function Figures 11 to 14 It was described in more detail.

[0067] A heat exchanger 80 is a device configured to transfer heat energy (particularly via a secondary fluid A, such as air) between a fluid W and its environment. Depending on the application and configuration, the heat exchanger 80 may include, for example, a heat exchanger or a chiller. The secondary fluid A is air used to heat and / or cool a building (particularly rooms within a building). According to an embodiment, the secondary fluid A may be driven through the heat exchanger 80 by a fan. In an embodiment, the secondary fluid A moves passively (i.e., due to wind or convection) through the heat exchanger 80. If the temperature of the fluid W is higher than the temperature of the secondary fluid A, the heat exchanger 80 provides energy to the secondary fluid A and in this case acts as a heater. If the temperature of the fluid W is lower than the temperature of the secondary fluid A, the heat exchanger 80 draws energy from the secondary fluid A and in this case acts as a cooler.

[0068] Valve 40 is a device for regulating the flow rate of fluid W through an orifice. Valve 40, arranged between the energy source and the heat exchanger 80, is configured to regulate the flow rate of fluid W to and from the heat exchanger 80.

[0069] HVAC system 1 may also include a fluid transfer system 60 for moving (heat transfer) fluids (e.g., liquids (e.g., water and / or refrigerant) or gases (e.g., air)) to and from heat exchanger 80. Fluid transfer system 60 may include fluid transfer lines (pipes or conduits) for guiding fluid flow through heat exchanger 80 and valve 40.

[0070] Figure 5B Another embodiment of the HVAC system 1 is shown, including a pump 90 for driving and controlling the flow of fluid W through a heat exchanger 80. A fluid transfer system 60 may be connected to an energy source, such as a heating device (furnace, heat pump) or a cooling device (refrigeration unit). Specifically, the fluid transfer lines include a supply pipe (or conduit) for supplying fluid from a valve 40 to the heat exchanger 80 and a return pipe (or conduit) for returning fluid from the heat exchanger 80. A controller 10, particularly for controlling the generation of pressure control signals for the pump 90, will be described below with reference to the diagram showing its structure. Figure 6 and about its function Figures 11 to 14 It is described in more detail.

[0071] Figure 6A highly schematic block diagram of a controller 10 according to the invention is shown. The controller 10 includes a processor 12, a memory for storing computer-readable instructions, and a communication interface 16 for receiving data signals (particularly setpoint thermal power transfer (PowerSP)) and for transmitting data signals (particularly control signals for controlling the orifice of valve 40). The processor 14 may include a central processing unit (CPU) for executing computer program code stored in the memory. In examples, the processor 14 includes a more specific processing unit such as an application-specific integrated circuit (ASIC), a reprogrammable processing unit such as a field-programmable gate array (FPGA), or a processing unit specifically configured to accelerate certain applications. The memory 14 includes one or more volatile (temporary) and / or non-volatile (non-temporary) storage components. The storage components are removable and / or non-removable and are also integrated wholly or partially with the controller 10. Examples of storage components include RAM (random access memory), flash memory, hard disk, data storage, and / or other data repositories. The memory 14 stores computer program code thereon configured to control the processor 12 of the controller 10, such that… Controller 10 (more generally, HVAC system 1) performs one or more steps and / or functions as described herein. Depending on the embodiment, the computer program code is compiled or uncompiled program logic and / or machine code. Accordingly, controller 10 is configured to perform one or more steps and / or functions. The computer program code defines discrete software applications and / or portions thereof. Those skilled in the art will understand that the computer program code may also be distributed across multiple software applications. The software applications are installed in controller 10. Alternatively, the computer program code may also be retrieved and executed by controller 10 as needed. In embodiments, the computer program code further provides an interface such as an API (Application Programming Interface) that allows the functions and / or data of controller 10 to be remotely accessed, such as via a client application or via a web browser. In embodiments, the computer program code is configured such that one or more steps and / or functions are not performed in controller 10, but rather in an external computing device (e.g., a mobile phone) and / or a remote server located in a different location from controller 10 (e.g., in a cloud-based computer system 10 (not shown)).

[0072] Figure 7 A highly schematic block diagram of a sensor module 50 according to an embodiment of the present invention is shown. The sensor module 50 includes a flow sensor 52 (such as an ultrasonic flow sensor) and a temperature sensor 54. The flow sensor 52 is configured and arranged between a valve 40 and a heat exchanger 80 to measure the flow rate Φ of the fluid passing through the heat exchanger 80 at the current position of the valve 40. actTemperature sensor 54 is configured and arranged between valve 40 and the fluid inlet side 82 of heat exchanger 80 to measure the supply temperature T of fluid W. IN Alternatively, a temperature sensor 54 is configured and arranged between valve 40 and the fluid return side 84 of heat exchanger 80 to measure the return temperature T of fluid W. out .

[0073] Figure 8 A block diagram of an actuator 20 for an HVAC system 1 according to an embodiment of the present disclosure is shown. As illustrated, the actuator 20 includes an electric motor 24 and electronic circuitry 22. The electric motor 24 is configured to move an actuated part, particularly a valve 40 coupled to the electric motor 24. The actuator 20 is configured to receive one or more control signals from a controller 10. The electronic circuitry 22 is connected to the electric motor 24 and configured to control the electric motor 24 according to one or more control signals.

[0074] Figure 9 An illustrative view of a controller 10 connected to an actuator 20 according to the invention is shown. The actuator 20 is mechanically coupled to a valve 40, which is arranged to regulate the flow rate of fluid W through a fluid transmission system 60.

[0075] Figure 10An illustrative view of a controller 10 connected to an actuator 20 is shown. The actuator 20 is mechanically coupled to a valve 40 including a six-way flow regulator 42. The six-way flow regulator 42 is capable of switching between a first operating mode (heating, e.g., at a 90° position of the valve) and a second operating mode (cooling, e.g., at a 0° position of the valve) based on control signals from the controller 10. As illustrated, the six-way flow regulator 42 includes: a first fluid input I1; a second fluid input I2; a fluid output O; a fluid return input RI; a first fluid return output RO1; and a second fluid return output RO2. The six-way flow regulator 42 can operate in the first operating mode, the second operating mode, and a third operating mode. In the first operating mode, the six-way flow regulator 42 enables fluid to flow from the first fluid input I1 toward the fluid output O and enables fluid to flow from the fluid return input RI toward the first fluid return output RO1. In the second operating mode, the 6-way flow regulator 42 allows fluid to flow from the second fluid input terminal I2 towards the fluid output terminal O and from the fluid return input terminal RI towards the second fluid return output terminal RO2. In the third operating mode, the 6-way flow regulator 42 prevents fluid from flowing between any of the following: the first fluid input terminal I1; the second fluid input terminal (I2); the fluid output terminal O; the fluid return input terminal RI; the first fluid return output terminal RO1; and the second fluid return output terminal RO2. To enable the same heat exchanger 80 to be used for both heating and cooling, the fluid input side 82 of the heat exchanger 80 is fluidly connected to the fluid output terminal O of the 6-way flow regulator 42, and the fluid return side 84 is fluidly connected to the fluid return input terminal RI of the 6-way flow regulator 42. The first fluid input terminal I1 of the 6-way flow regulator 42 is fluidly connected to a fluid source at a first temperature, and the second fluid input terminal I2 of the 6-way flow regulator 42 is fluidly connected to a fluid source at a second temperature, the first temperature being different from the second temperature.

[0076] In the following paragraphs, refer to Figures 11 to 14 The description describes a sequence of steps performed according to embodiments of the present disclosure to control the orifice (opening or position) of valve 40 to regulate the flow rate ΦW of fluid W through heat exchanger 80 of HVAC system 1 and thereby adjust the heat power transfer through heat exchanger 80.

[0077] Figure 11 A simplified flowchart of a first embodiment of a method for controlling the heat power transfer of a heat exchanger 80 in an HVAC system 1 according to the present invention is shown. In the first step S10 of the method according to the invention, the setpoint heat power transfer Power SP is received by the controller 10. According to embodiments of the present disclosure, the setpoint heat power transfer Power SP may be a constant value or a variable function.

[0078] In a further subsequent or simultaneous step S20, the flow rate Φ of the fluid passing through the heat exchanger 80 is measured by the flow sensor 52. act .

[0079] In step S30, the measured flow rate Φ of the fluid is used. act The controller 10 determines the estimated heat power transfer, Power EST, based on a defined flow rate to ΔT mapping. According to an embodiment of this disclosure, step S30 includes the controller 10 determining the estimated heat power transfer, Power EST, based on the measured flow rate Φ of the fluid W. act Determine the estimated temperature difference ΔT on the heat exchanger 80, where the controller 10 is based on the measured fluid flow rate Φ. act The estimated heat power transfer (Power EST) is determined by estimating the temperature difference ΔT.

[0080] After determining the estimated thermal power transfer Power EST, in step S40, the controller 10 compares the setpoint thermal power transfer Power SP with the estimated thermal power transfer Power EST.

[0081] In the subsequent step S50, the controller 10 controls the flow rate Φ of fluid W by generating a control signal based on comparison. act According to the embodiments disclosed herein, controller 10 controls the flow rate Φ of fluid W by generating a control signal based on comparison. act This is to minimize the difference between the setpoint thermal power transfer Power SP and the estimated thermal power transfer Power EST.

[0082] Figure 12 A simplified flowchart of another embodiment of a method for controlling the transfer of heat power in a heat exchanger 80 in an HVAC system 1 is shown, the method further comprising the step S26 of defining the flow rate to ΔT as the relationship between the flow rate of fluid W through the heat exchanger 80 and the temperature difference ΔT on the heat exchanger 80.

[0083] According to embodiments of this disclosure, the mapping from flow rate to ΔT is defined based on calculations and / or mathematical models and / or measurements of temperature difference and flow rate on the heat exchanger.

[0084] Figure 13 A simplified flowchart illustrating yet another embodiment of a method for controlling heat power transfer in a heat exchanger 80 within an HVAC system 1 is shown. In step S27, the return temperature T of the fluid W is measured by temperature sensor 54. out Subsequently, in step S28, the return temperature T of fluid W is measured. IN Calibrate the mapping of flow rate to ΔT.

[0085] Figure 14A simplified flowchart illustrating one or more embodiments of a method for controlling the orifice of valve 40 in HVAC system 1, wherein the flow rate Φ of fluid W through heat exchanger 80 is regulated. act This includes generating a valve control signal for controlling the orifice of valve 40 in HVAC system 1. In step S54, following step S50, the controller 10 transmits the valve control signal to the actuator 20. Subsequently, in step S56, the actuator 20 actuates valve 40 according to the valve control signal to control the orifice of valve 40.

[0086] Reference number list

[0087] Power transfer Q Fluid flow rate Φ The flow rate Φ of the measured fluid act Temperature difference ΔT Supply temperature T IN Return temperature T out Setpoint heat power transfer Power SP Estimated heat power transfer Power EST Controller 10

[0088] (Controller) Processor 12

[0089] (Controller) Memory 14

[0090] (Controller) Communication Interface 16 Actuator 20

[0091] (Actuator) Electronic Circuit 22

[0092] (Actuator) Electric motor 24 Valve 40

[0093] 6-channel flow regulator 42

[0094] (6-channel flow regulator) First fluid input terminal I1

[0095] (6-channel flow regulator) Second fluid input terminal I2

[0096] (6-channel flow regulator) Fluid output terminal O (6-channel flow regulator) Fluid return input RI (6-channel flow regulator) First fluid return output terminal RO1

[0097] (6-channel flow regulator) Second fluid return output terminal RO2 Sensor Module 50 Flow sensor 52 Temperature sensor 54 Fluid transport system 60 Heat exchanger 80 (Heat exchanger) Fluid inlet side 82 (Heat exchanger) Fluid return side 84 Pump 90 Saturation point (SAT).

Claims

1. A method for controlling the heat power transfer of a heat exchanger (80) in an HVAC system (1), the method comprising: - The setpoint thermal power transfer (Power SP) is received by the controller (10); - The flow rate (Φ) of the fluid (W) passing through the heat exchanger (80) is measured by the flow sensor (52). act ); - The flow rate (Φ) of the measured fluid is used by the controller (10). act The estimated heat power transfer (Power EST) is determined by mapping the defined flow rate to ΔT. - The controller (10) compares the setpoint thermal power transfer (Power SP) and the estimated thermal power transfer (Power EST); and Based on the comparison, the controller (10) adjusts the flow rate (Φ) of the fluid (W) through the heat exchanger (80). act ).

2. The method according to claim 1, -in, Adjusting the flow rate (Φ) of the fluid (W) passing through the heat exchanger (80) act This includes valve control signals generated by the controller (10) based on the comparison for controlling the orifices of valves (40) in the HVAC system (1); and -wherein, the flow rate (Φ) of the fluid (W) act The flow rate is measured by the flow sensor (52) at the current position of the valve (40).

3. The method according to claim 2, further comprising: - The controller (10) transmits the valve control signal to the actuator (20) mechanically coupled to the valve (40); as well as The actuator (20) actuates the valve (40) according to the valve control signal.

4. The method according to any one of claims 1 to 3, wherein: - Adjust the flow rate (Φ) of the fluid (W) passing through the heat exchanger (80). act This includes a pressure control signal generated by the controller (10) based on the comparison for controlling the supply pressure of the fluid (W); and -wherein, the flow rate (Φ) of the fluid (W) act The flow rate is measured by the flow sensor (52) at the current supply pressure of the fluid (W).

5. The method of claim 1, further comprising defining the flow rate to ΔT mapping as a relationship between the flow rate of the fluid (W) through the heat exchanger (80) and the temperature difference (ΔT) of the fluid (W) on the heat exchanger (80).

6. The method according to claim 1, wherein, The mapping from flow rate to ΔT is defined based on one or more of the following: -The heat transfer characteristic curve of the heat exchanger (80); - The heat transfer coefficient of the heat exchanger (80); - The thermal conductivity of the heat exchanger (80); - The flow rate and / or temperature of the secondary fluid (ΦA) surrounding the heat exchanger (80); - The convective heat transfer coefficient of the fluid (W); - The current operating mode of the heat exchanger (80); -The type of heat exchanger of the heat exchanger (80); - Geometric data of the heat exchanger (80).

7. The method of claim 1, further comprising the flow rate (Φ) measured by the controller (10) based on the fluid (W). act Determine the estimated temperature difference (ΔT) of the fluid (W) on the heat exchanger (80). in, The controller (10) is based on the measured flow rate (Φ) of the fluid. act The estimated heat power transfer (Power EST) is determined by the estimated temperature difference (ΔT).

8. The method according to claim 1, further comprising: - Data indicating the following items are measured or received by the temperature sensor (54): -The supply temperature (T) of the fluid (W) IN ); - The return temperature (T) of the fluid (W) out );or - The temperature (T) of the secondary fluid (ΦA) passing through and / or surrounding the heat exchanger (80) sec ), - Use the following to calibrate the mapping of the flow rate to ΔT: -The supply temperature (T) IN ), - The return temperature (T) of the fluid (W) out ),or -The temperature (T) of the secondary fluid (ΦA) sec ).

9. A controller (10) for controlling the heat power transfer of a heat exchanger (80) in an HVAC system (1), the controller (10) comprising a processor (12) configured to perform the method according to any one of claims 1 to 8.

10. An HVAC system (1), comprising: - Heat exchanger (80); - Controller (10); as well as - A flow sensor (52) configured to measure the flow rate (Φ) of the fluid (W) passing through the heat exchanger (80). act ); The controller (10) is configured to: - Use the measured flow rate (Φ) of the fluid (W) act The mapping from the defined flow rate to ΔT is used to determine the estimated heat power transfer (Power EST). -Based on comparison, the flow rate (Φ) of the fluid (W) passing through the heat exchanger (80) is generated for regulating the flow rate (Φ). act ) control signals.

11. The HVAC system (1) according to claim 10, further comprising: - Valve (40), which has an orifice; as well as -Actuator (20), which is mechanically connected to the valve (40); The control signals generated by the controller (10) include valve control signals for controlling the orifices of the valves (40) of the HVAC system (1). The controller (10) is further configured to transmit the valve control signal to the actuator (20), and The actuator (20) is configured to actuate the valve (40) of the orifice according to the valve control signal in order to regulate the flow rate (Φ) of the fluid (W) passing through the heat exchanger (80).

12. The HVAC system (1) of claim 11 further includes a pump (90) for driving the fluid (W) through the heat exchanger (80). in, The control signals generated by the controller (10) include pressure control signals for controlling the supply pressure of the fluid (W). The controller (10) is further configured to transmit the pressure control signal to the pump (90), and The pump (90) is configured to drive the fluid (W) through the heat exchanger (80) at a supply pressure according to the pressure control signal.

13. The HVAC system (1) according to claim 11 or 12, wherein, The valve (40) includes a 6-way flow regulator (42), the 6-way flow regulator (42) including: - First fluid inlet (I1); - Second fluid inlet (I2); - Fluid outlet (O), which is fluidly connected to the fluid inlet side (82) of the heat exchanger (80); - Fluid return input (RI), which is fluidly connected to the fluid return side (84) of the heat exchanger (80); - First fluid returns to the output terminal (RO1); and - The second fluid returns to the output (RO2). The actuator (20) is configured to control the six-channel flow regulator (42) in a first operating mode and a second operating mode according to the valve control signal: In the first operating mode, controlling the orifice of the 6-way flow regulator (42) enables: - The flow rate (Φ) of the regulating fluid (W) from the first fluid inlet (I1) toward the fluid outlet (O); and - The flow rate (Φ) of the regulating fluid (W) from the fluid return input (RI) toward the first fluid return output (RO1), and In the second operating mode, controlling the orifice of the 6-way flow regulator (42) enables: - The flow rate (Φ) of the regulating fluid (W) from the second fluid inlet (I2) toward the fluid outlet (O); and - The flow rate (Φ) of the regulating fluid (W) from the fluid return input (RI) toward the second fluid return output (RO2).

14. A computer program product comprising instructions which, when executed by a processor (12) of a controller (10) of an HVAC system (1) comprising a heat exchanger (80) and a flow sensor (52), cause the HVAC system (1) to perform the method according to any one of claims 1 to 8.

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