METHOD FOR CONTROLLING COOLING OR HEATING CAPACITY FOR A MULTI-SOURCE HEATING / COLD SYSTEM AND CONTROL DEVICE FOR EXECUTING THE METHOD

Description

[0001] The invention relates to a method for controlling a cooling or heating output according to patent claim 1 and a control device for carrying out the method according to patent claim 13. State of the art

[0002] In the state of the art it is known to use various heat sinks, e.g.

[0003] To forward different temperature requirements to a control unit for rooms in a building. The control unit determines an operating parameter for the heat source or cooling source and controls the source accordingly so that the heat sink is supplied with the desired heat or cooling output. In modern heating and cooling systems for supplying rooms with heat or cooling output, different heat sources or cooling sources are used to generate the heat or cooling output. For example, a heating system can have a solar panel system, a heat pump, a gas boiler or an electric heater as a heat source. In previous systems, the heat sources were controlled independently of one another in order to provide the heat or cooling output required for the heat sinks.

[0004] From US 2007 / 0044501 A1 and EP 2615385 A1, methods for controlling a cooling or heating output for a heating / cooling system with multiple sources are known, wherein in a first step a request from the at least one heat sink for a heating output or cooling output is detected, wherein in a second step at least one boundary condition of the at least one source is detected, and wherein in a third step an operating state of at least one source is determined depending on a strategy. Disclosure of the invention

[0005] The object of the invention is to provide an improved method for operating a heating / cooling system with at least one source for supplying at least one heat sink with the desired heating or cooling output.

[0006] The object of the invention is achieved by the method according to claim 1 and by the control device according to claim 13. Further advantageous embodiments are specified in the dependent claims.

[0007] An advantage of the described method is that sources are used according to their boundary conditions and dependent on a selectable strategy in such a way that the heat sinks are supplied with a heating output and / or a cooling output. In a first step, a request from the heat sinks is detected, in a second step at least one boundary condition of the at least one source is detected and in a third step, depending on the strategy, an operating state of at least one of the sources is determined in order to supply the heat sink with a cooling or heating output. Preferably, boundary conditions of at least two sources are detected in the second step and taken into account in the third step in order to determine the operating state of at least one source depending on the strategy.

[0008] In the second step, the operating state of at least one source is recorded as whether the source is in heating mode or cooling mode. In the third step, a decision is made as to whether the operating state of the source should be changed, depending on the boundary conditions of the sources and the operating state of the source. This allows for optimal adjustment of the operating state of the source(s) to supply the heat sink with the desired heating or cooling output.

[0009] According to the present invention, the desired strategy is to provide the heating and / or cooling output, for example, cost-effectively and / or efficiently and / or with low exhaust emissions and / or with a high level of comfort and / or as quickly as possible. For this purpose, diagrams, characteristic curves or formulas are stored, for example, which describe the operation of the sources depending on the desired strategy. By comparing the diagrams, characteristic curves and formulas, it can be determined which of the sources can best supply which heating and / or cooling output according to the desired strategy. For example, it can be advantageous to provide the heating or cooling output supplied by a heat sink up to a desired temperature from the first source and above the desired temperature from a second source.In addition, it can be advantageous to have the heat sink supplied with the desired cooling and / or heating output for a short time and then with a longer-term supply of the heat sink with cooling and / or heating output from a second source. In a further embodiment, two or more heat sinks can be provided which are supplied with cooling and / or heating output from one or more heat sources. Depending on the boundary conditions of the sources and regardless of the requests and boundary conditions of the heat sinks, it can be advantageous, for example, to supply one heat sink with heating output from one source and the other heat sink with heating output from another source. In addition, it can be advantageous if one heat sink requires heating output and the other heat sink requires cooling output, for example if both heat sinks are supplied with a heat or cooling source.Cooling capacity. It may also be advantageous to supply both heat sinks with heat output or cooling capacity from different sources. One advantage of the described method is that the capabilities of the individual sources are optimally utilized according to the desired strategy, depending on the requirements and constraints of the heat sinks or the heat sink.

[0010] According to the invention, a characteristic curve and / or a characteristic map and / or a formula for providing the cooling and / or heating output as a function of at least one parameter are provided as boundary conditions for the sources, wherein the parameter is from the following group: costs, efficiency, exhaust gas production, outside temperature, time of day, time of year, outside temperature. An operating point of the source, in particular the heating or cooling operating mode, can be defined. With the help of at least one of these parameters, it is possible to optimally utilize the performance of the sources. The predetermined strategy is to provide the heating and / or cooling output cost-effectively and / or efficiently and / or with low exhaust gas values ​​and / or with a high level of comfort and / or as quickly as possible.In one embodiment, a cooling capacity or a heating capacity, in particular a desired room temperature, is taken into account as a request of the heat sink when controlling the heat sources.

[0011] In one embodiment, a desired humidity, in particular a range or a lower limit or an upper limit for a desired humidity, is taken into account as a request from the heat sink when controlling the heat sources.

[0012] In a further embodiment, the heat sink is designed, for example, in the form of a room in a building, and the boundary condition taken into account is an outside temperature of the building and / or the weather, in particular sunshine, i.e. direct solar radiation on a building wall or a window, and / or a time of day, and / or a time of year, and / or an outside temperature averaged over a specified period, and / or a current inside temperature, and / or a humidity in the room. At least one of these boundary conditions, in particular at least two of these boundary conditions, and advantageously more than two of these boundary conditions, can be taken into account in order to carry out optimal selection or control of the two sources for supplying the room with the required heating and / or cooling output.

[0013] Characteristic curves, diagrams, or formulas are stored for the aforementioned boundary conditions. These can be used to determine the parameters, particularly the boundary conditions of the heat sinks, depending on the boundary conditions. This allows for optimal adaptation of the utilization of the available sources to provide cooling and / or heating output.

[0014] Depending on the chosen design, the boundary condition taken into account is whether a source can provide cooling capacity and / or heating capacity.

[0015] In a further embodiment, requests and / or boundary conditions of the heat sink are taken into account to decide whether a request for heat output or cooling output is sent to the heating / cooling system. In a further embodiment, boundary conditions of the sources are taken into account to determine an operating point, in particular an operating mode of at least one of the sources, depending on the request and to deliver a cooling output and / or a heat output to the heat sink. This provides a two-stage method that enables an optimized provision of heat and / or cooling output.

[0016] In a further embodiment, the boundary conditions and / or demands of the heat sink and / or source are taken into account using a factor. This makes it possible to consider the various demands and boundary conditions of the heat sinks and / or sources in such a way that optimal utilization of the sources is possible according to the desired strategy and, moreover, optimal provision of the desired cooling and / or heating output from the heat sinks is achieved.

[0017] In one embodiment, the sources are connected to the heat sink via a hydraulic piping system, wherein boundary conditions of the piping system, in particular the presence of valves, mixers, the usability of piping in one or two directions are taken into account in order to determine an operating mode of at least one of the sources and an operating mode of the piping system for supplying the heat sink with heating or cooling power.

[0018] Depending on the selected design, two types of sources can be used. The first type of source is designed to operate in either a heating mode or a cooling mode. The second type of source is designed to operate in both a heating mode and a cooling mode.

[0019] The invention is explained in more detail below with reference to the figures.

[0020] It shows Fig. 1 a schematic representation of a building with several rooms, and Fig. 2 a schematic representation of a system for providing heating and / or cooling capacity.

[0021] Fig. 1 shows a schematic representation of a building 1 in which several rooms 2, 3, 4, 5, 6, 7 are provided. Each room represents a heat sink, i.e. for each room, heat or cooling power is provided by a heating / cooling system, i.e. by a thermal system 8, depending on the demand from the heat sink. The thermal system 8 is arranged, for example, in a basement of the building 1 and has a first, a second and a third source 9, 10, 11. The three sources 9, 10, 11 represent thermal systems with which heat and / or cooling power can be generated. For example, the first source 9 can be a thermal solar system, the second source 10 a heat pump and the third source 11 a gas boiler. Each of the sources 9, 10, 11 has a further control device 14, 15, 16, with which the operating point, in particular the operating mode, e.g. cooling or heating, of the sources 9, 10, 11 is controlled.In addition, a control unit 12 is provided, which is connected to the other control units 14, 15, 16 of sources 9, 10, 11. The control unit 12 is also connected to a memory 13. Programs, data, characteristic curves, diagrams, and calculation methods are stored in the memory 13.

[0022] Depending on the chosen embodiment, the control unit 12 can be part of the thermal system 8, in particular one of the sources 9, 10, 11, or it can be installed in one of the rooms 2, 3, 4, for example, in the form of a central controller located in a single unit. The control unit 12 can also be part of an external device, such as a mobile phone or computer.

[0023] A sensor 18 and an input device 17 can be provided in each room 2 to 7. The sensor 18 is provided, for example, to measure the temperature and / or humidity in the room. The input device 17 is provided so that a user of the room can enter, for example, a desired room temperature and / or a desired humidity. The input device 17 is also designed to forward the entered data to the control unit 12.

[0024] Furthermore, each room can have a calculation unit 19, which is connected to the sensor 18 and the input device 17. The calculation unit 19 is designed to determine a specific heating and / or cooling output or a temperature profile, for example depending on the actual temperature of the room and / or the air humidity of the room and / or the temperature and / or air humidity desired by a user via the input device 17, and to forward it to the control unit 12. When determining the desired temperature, air humidity or the desired heating or cooling output, the calculation unit 19 can use further parameters as boundary conditions of the room, such as an outside temperature outside the room or outside the building, a weather, i.e.direct sunlight, rain, snow, cloud cover, a time of day, a season and / or an average outside temperature must be taken into account when determining the desired temperature, humidity or the desired cooling and heating output.

[0025] Thus, the calculation unit 19 can calculate an optimal control of the temperature of the room or of the heat output or cooling output supplied to the heat sink for the corresponding heat sink, i.e. the corresponding room, and transmit this to the control unit 12. For this purpose, the calculation unit 19 has a second memory 20 in which characteristic curves, characteristic maps, and calculation methods are stored in order to determine a desired target temperature or a curve of the target temperature or a desired cooling output or heat output depending on at least the current room temperature, the desired room temperature and at least one boundary condition such as the air humidity in the room, the outside temperature, the weather, the time of day, the time of year, the average outside temperature.

[0026] Depending on the selected embodiment, each input device 17 of each room can transmit corresponding information and / or each calculation unit 19 of each room can transmit a corresponding desired cooling or heating output to the control unit 12. Depending on the selected embodiment, the calculation units 19 can also be omitted.

[0027] Fig. 2shows a schematic representation of a control system with a thermal system 8, which has three sources 9, 10, 11, which are controlled by the control unit 12. Depending on the selected design, more or fewer sources can be provided. As an example, three heat sinks 2, 3, 4 are shown schematically, which represent, for example, rooms of a building. Depending on the selected design, more or fewer heat sinks can be provided. The mode of operation is explained using the first heat sink 2, wherein the heat sinks 2, 3, 4 have the same devices. The calculation unit 19 of the first heat sink 2 records, as already explained, inputs from a user via the input device 17, which may, for example, include a desired temperature, a desired temperature profile, a desired air humidity or other specifications.In addition, the calculation unit 19 uses the sensor 18 to detect boundary conditions for the first heat sink 2, such as the current room temperature, the current air humidity, an outside temperature, and other boundary conditions. Based on the available data, the calculation unit 19 determines a request for a specific heating and / or cooling output for the first heat sink 2. The request is transmitted to the control unit 12. For this purpose, the calculation unit 19 is connected to the control unit 12 via a control line 26. The control unit 12, in turn, is connected to the sources 9, 10, 11 via a second control line 28. Depending on the selected embodiment, the connection can also be wireless.

[0028] In an analogous manner, the calculation units 19 of the second and third heat sinks 3, 4 also transmit a request for a specific heating and / or cooling output to the control unit 12.

[0029] In a further embodiment, the input device 17 can be omitted, wherein the desired temperature and / or humidity is preset, for example.

[0030] In a further embodiment, the calculation unit 19 can be omitted, and the user's inputs into the input device 17 are transmitted from the input device 17 as a request to the control unit 12. In addition, individual or all known boundary conditions of the heat sink 2 can be transmitted to the control unit 12.

[0031] At least one strategy for operating sources 9, 10, 11 is stored in memory 13 of control unit 12. The strategy may, for example, consist of providing the heat sink's demand quickly, efficiently, cost-effectively, with maximum comfort, at minimum cost, with minimum pollutant emissions, and with maximum source efficiency.

[0032] In addition, the control unit 12 is supplied via an input 27 with further data or boundary conditions such as the outside temperature, an average outside temperature, a time of year, an operating state of the first, the second and / or the third source 9, 10, 11, a boundary condition for operating the source 9, 10, 11.

[0033] For example, input 27 can be a sensor input. Input 27 can also receive data externally, e.g., via an internet service.

[0034] The operating state of the source 9, 10, 11 can, for example, be a specific operating point or an operating mode such as cooling or heating. Depending on the selected design, the source can be configured to operate only in cooling mode or only in heating mode. Furthermore, the source can be configured to operate in cooling mode or heating mode.

[0035] Parameters that influence or limit the functioning of sources 9, 10, 11 can be taken into account as boundary conditions for sources 9, 10, 11. For example, the weather, i.e. the presence of sunshine or cloud cover or the outside temperature, can be taken into account as a parameter in a solar thermal system. Furthermore, the efficiency of a heat pump can be taken into account as the operating state. Furthermore, for a source in the form of a gas boiler, for example, the gas price can be taken into account. Furthermore, when using an oil heating system, the storage tank or the oil price can be taken into account. Furthermore, when designing a source as a thermal power system, it can be taken into account whether electrical output is required instead of heating or cooling output.

[0036] Each of the sources 9, 10, 11 can be connected directly or via switching valves, mixers, pumps with hydraulic lines to a heat exchanger 29 of the heat sinks 2 to 7. Furthermore, the design of the heat exchanger 29 can be considered as a parameter for the heat sink. For example, the heat exchanger can be designed as an underfloor heating system, a wall heating system, a radiator, or a heat exchanger with a fan. Furthermore, the source 9, 10, 11 can also be designed as an electric heating or cooling device arranged in the heat sink 2, 3, 4.

[0037] Alternatively, each of the existing sources can be connected to each of the existing heat sinks, or to all heat sinks simultaneously. Likewise, the existing sources can be connected to only a portion of the existing heat sinks. The existing hydraulics are taken into account by the strategy.

[0038] Each calculation unit 19 can have its own control method with which, depending on a user input or a predetermined target temperature, a request for the supply of heating or cooling power by the thermal system 8 can be made independently of boundary conditions according to predetermined procedures, characteristic curves and / or diagrams.

[0039] In addition, the calculation unit 19 can have limit values ​​for the boundary conditions, particularly operating conditions. These limit values ​​are used to prevent excessive switching between different requests or switching between requests for heating output or requests for cooling output. Furthermore, a time factor can be considered, for example, as a damping factor, which specifies that a new request may only be transmitted to the control unit 12 after certain periods of time, such as 15 minutes.

[0040] A boundary condition for a heat sink is, for example, the type of heat exchanger 29 present in the heat sink 2, 3, 4. The heat exchanger 29 can, as explained above, be designed as a radiator, underfloor heating, air heating, electric heating, electric cooling, or electric air conditioning. Depending on the existing conditions, the calculation unit 19 determines, for example, a specific water temperature as a request that should be supplied by the heating / cooling system 8 to operate the underfloor heating or the radiator. The calculation unit 19 thus performs a local determination of an optimal request.

[0041] The control unit 12, on the other hand, performs global control of the heating or cooling output provided by the thermal system 8. The requests of at least one, preferably all, heat sinks and the operating states of the sources 9, 10, 11 are taken into account, for example, to determine an operating state of at least one source, in particular all sources, or to implement a change in the operating state of the sources or at least one source. A change in the operating state can, for example, consist of switching a source from a heating mode to a cooling mode.

[0042] The sources are deployed according to the boundary conditions and depending on the predefined or selectable strategy in such a way that the heat sink is supplied with a desired heat output and / or cooling output. A request from the heat sink is detected. Furthermore, boundary conditions of the two sources are detected, and depending on the strategy, an operating state of at least one source is determined in order to supply the heat sink with a cooling or heating output. For this purpose, corresponding characteristic curves, diagrams, and / or calculation methods are stored in memory 13, which determine the operating state of the source depending on the boundary conditions of the source and the request from the heat sink.

[0043] For example, the operating state of at least one source is recorded as whether the source is in heating mode or cooling mode. Depending on the boundary conditions of the sources and the operating state of the source, a decision is then made as to whether or not to change the operating state of the source. In this way, all sources can be monitored and optimally controlled by the control unit 12. This allows for optimal adjustment of the operating state of the source(s) to supply the heat sink with the desired heating or cooling output.

[0044] The boundary conditions of the sources can include, for example, limit values ​​for switching between the provision of heat output or the provision of cooling output, switching frequencies, a maximum or minimum operating temperature during the cooling mode or the heating mode of the source, etc. In addition, the control unit 12 can have limit values ​​for the boundary conditions of the sources 9, 10, 11, in particular operating conditions of the sources. The limit values ​​are used to avoid too frequent switching between different operating states, in particular switching between heat output or cooling output. In addition, a time factor can be taken into account, for example, as a damping factor, which specifies that the source may only be switched back and forth between a cooling mode and a heating mode after certain periods of time, such as one hour or one day.

[0045] Furthermore, the control unit 12 can use a time-averaged outside temperature as a boundary condition, which determines whether a source is operated in heating or cooling mode. For example, if the outside temperature averaged over a day is above a specified reference value, at least one source can be switched from heating to cooling mode.

[0046] The control unit 12 can pursue various strategies to provide a desired heating or cooling output for at least one heat sink. The strategy can be predefined or selected or adjusted by a user using an input device. The strategy can take into account the type of source, boundary conditions of the sources, and / or boundary conditions of the thermal system, such as the design of the hydraulic piping system, to control the operating state of at least one source.

[0047] For example, a majority decision can be used as a strategy. Depending on whether more sinks request cooling or heating, at least one source or all sources are switched to heating or cooling mode. Another strategy can be a mutual agreement strategy. In this case, a source operating state—i.e., switching from cooling to heating mode or vice versa—is only executed if all sinks request a changed mode, i.e., cooling instead of heating.

[0048] Another strategy involves prioritizing a selected operating mode. For example, if heating mode is prioritized, all sources are in cooling mode, and a temperature of 5°C is reached during the night, for example, the system automatically switches to heating mode to protect the Thermosystem 8 from frost.

[0049] In a further embodiment, a strategy is selected which is predetermined by the outside temperature. In this case, depending on the outside temperature, it is predetermined whether the at least one source is operated in heating mode or cooling mode. To avoid excessively frequent fluctuations, for example, time-averaged outside temperatures or different switching points spaced a few degrees Celsius apart are used to switch from cooling mode to heating mode and from heating mode back to cooling mode. For example, if the outside temperature exceeds 23°C, the system can switch to cooling mode, and if the outside temperature falls below 17°C, the system can switch to heating mode. The outside temperature can, for example, be averaged over an hour. Furthermore, the interval between two switching points can also have a different value, for example 3°C.In addition, a strategy can also be used that consists of a combination of the strategies described.

[0050] Furthermore, a strategy can be designed such that one source is designated for basic supply, such as a heat pump, another source is used preferentially, such as a solar thermal system, and a third source is used for rapid temperature changes or peak loads, such as a gas boiler. Furthermore, it can be provided that unused sources are used to generate electricity.

[0051] The described method has the advantage that the calculation unit 19 transmits an optimal request to the control unit 12 for each sink. The control unit 12 knows the conditions of the available sources and their operating status. Furthermore, a strategy for operating the sources is specified for the control unit 12. Thus, depending on the specified strategy and the available sources, the control unit 12 can provide optimal heating or cooling output depending on the requested heating or cooling output. This method enables optimization in the operation of the sources.

Claims

1. Method for controlling a heating / refrigerating system (8) comprising at least one source (9, 10, 11) for providing a cooling and / or heating output for at least one heat sink (2, 3, 4, 5, 6, 7), in particular a room of a building (1), wherein, in a first step, a request of the at least one heat sink (2, 3, 4, 5, 6, 7) for a heating output or refrigerating output is detected, wherein, in a second step, at least one boundary condition of the at least one source (9, 10, 11) is detected, wherein the boundary condition for the sources (9, 10, 11) that is used is a characteristic curve, a characteristic diagram or a formula for providing the refrigerating and / or heating output on the basis of at least one parameter, the parameter being from the following group: cost, efficiency, exhaust gas generation, outside temperature, time of day, time of year, an average outside temperature, promptness of the provision, comfort, wherein, during the second step, at least for one source (9, 10, 11) as operating state it is detected whether the source is in heating mode or in cooling mode, and wherein, in a third step, a strategy is taken as a basis to define an operating state of at least one source (9, 10, 11), wherein, during the third step, the at least one boundary condition of the at least one source (9, 10, 11), the operating state of the at least one source (9, 10, 11) and the strategy are taken as a basis to make a decision as to whether the operating state of the source (9, 10, 11) is changed, wherein the specified strategy consists in providing the heating and / or refrigerating output inexpensively and / or efficiently and / or with low exhaust gas values and / or with high comfort and / or as quickly as possible.

2. Method according to Claim 1, wherein the boundary condition of the heat sinks (2, 3, 4, 5, 6, 7) that is taken into account is an outside temperature and / or the weather and / or a time of day and / or a time of year and / or an outside temperature averaged over time and / or a temperature inside the heat sink (2, 3, 4, 5, 6, 7) and / or a humidity in the heat sink (2, 3, 4, 5, 6, 7).

3. Method according to either of the preceding claims, wherein requests made by and / or boundary conditions of the heat sink (2, 3, 4, 5, 6, 7) are taken into account in order to make a decision as to whether a request for heating output or cooling output is sent to the heating / refrigerating system (8).

4. Method according to Claim 3, wherein the boundary conditions of the sources (9, 10, 11) are taken into account in order, on the basis of the request, to define an operating point, in particular an operating mode, of at least one of the sources (9, 10, 11) and to supply a refrigerating output and / or a heating output to the heat sink (2, 3, 4, 5, 6, 7).

5. Method according to one of the preceding claims, wherein requests made by and / or boundary conditions of the heat sink (2, 3, 4, 5, 6, 7) and / or the boundary conditions of the sources (9, 10, 11) are taken into account with a factor, and wherein at least two requests made by and / or two boundary conditions of the heat sinks (2, 3, 4, 5, 6, 7) are taken into account in order to define an operating mode of the sources (9, 10, 11).

6. Method according to one of the preceding claims, wherein the at least one source (9, 10, 11) is connected to one or more heat sinks via a hydraulic line system, wherein boundary conditions of the line system, in particular the presence of valves, of mixers or the usability of lines in two directions are taken into account in order to define an operating mode of the sources (9, 10, 11) and an operating mode for the use of the line system of the heat sink (2, 3, 4, 5, 6, 7) with heating or refrigerating output.

7. Method according to one of the preceding claims, wherein at least a second heat sink (2, 3, 4, 5, 6, 7) is provided, wherein requests made by and / or boundary conditions of the second heat sink (2, 3, 4, 5, 6, 7) are taken into account in order to make a decision as to whether a request for heating output or cooling output is sent to the heating / refrigerating system (8) by the second heat sink (2, 3, 4, 5, 6, 7), and wherein boundary conditions of the sources (9, 10, 11) are taken into account in order, on the basis of the requests made by the two heat sinks (2, 3, 4, 5, 6, 7), to define an operating point, in particular an operating mode of the two sources (9, 10, 11) and supply a refrigerating output and / or a heating output to the heat sinks (2, 3, 4, 5, 6, 7).

8. Method according to one of Claims 3 to 7, wherein boundary conditions averaged over time of the at least one source (9, 10, 11) are taken into account in order, on the basis of the request made by at least one heat sink (2, 3, 4, 5, 6, 7), to define operating modes of the sources (9, 10, 11) and to supply a refrigerating output and / or a heating output to the heat sinks (2, 3, 4, 5, 6, 7).

9. Method according to one of the preceding claims, wherein the at least one source (9, 10, 11) is designed to be operated either in a heating mode or in a cooling mode or in a heating mode and in a cooling mode.

10. Method according to one of the preceding claims, wherein a time factor is taken into account as damping factor, wherein the time factor defines that a switch back and forth between a cooling mode and a heating mode of the source (9, 10, 11) is only made after certain periods of time.

11. Method according to one of the preceding claims, wherein the boundary condition taken into account of the heat sink (2, 3, 4, 5, 6, 7) is an outside temperature averaged over time.

12. Method according to one of the preceding claims, wherein use is made of different switchover points for the outside temperature of a few degrees Celsius, in order to switch a source (9, 10, 11) from a cooling mode back to the heating mode and from the heating mode back to the cooling mode.

13. Control unit (12) designed to carry out a method according to one of the preceding claims.