WO2012098288A1

WO2012098288A1 - Method, apparatus and computer program product for controlling an actuator when adjusting a temperature

Info

Publication number: WO2012098288A1
Application number: PCT/FI2012/050030
Authority: WO
Inventors: Eino Hintsala
Original assignee: Ouman Oy
Priority date: 2011-01-19
Filing date: 2012-01-13
Publication date: 2012-07-26
Also published as: EP2665974A4; FI20115051L; FI126110B; FI20115051A0; EP2665974A1; FI20115051A

Abstract

In the invention an actuator (303) of a thermal adjustment device (306) is controlled for adjusting the temperature in a target. For controlling the actuator there are three adjustment blocks: a first adjustment block (304), a second adjustment block (302) and a third adjustment block (305). The adjustment block is a functional entity, which concentrates on the adjustment of the operation of some specific area. The adjustment blocks can be implemented with different devices or combinations of devices or with programs functioning in devices or in a device. Dynamic operating limits, at least a maximum and a minimum, are in the method calculated in the first adjustment block based on scaling constants and scaling variables. The dynamic operating limits change based on the scaling variables. For example when the outside temperature drops, the maximum of the dynamic operating limits can increase. The control signal is defined in the second adjustment block, and it is defined based on the goal temperature, where it is desired for the temperature of the target to settle, and the measured temperature of the target. The dynamic operating limits and the control signal are read and an output signal is calculated in the third adjustment block for controlling the actuator by scaling the control signal with the dynamic operating limits, and the actuator, which controls the thermal adjustment device, is controlled based in the output signal. The output signal can thus vary from the minimum of the dynamic operating limit to the maximum of the dynamic operating limit.

Description

Method, apparatus and computer program product for controlling an actuator when adjusting a temperature

The invention relates to a method, an apparatus and a computer program product for controlling an actuator of a thermal adjustment device when adjusting the temperature in a target.

A thermal adjustment device is used for heating or cooling different targets, such as buildings and their rooms. Thermal adjustment devices are for example radiators with liquid circulation, different electric heaters, floor or ceiling heating arrangements, air-conditioning devices and other corresponding devices, which are used to strive to adjust the temperature of a target as desired. The heating is done either by producing heat on site or by bringing it from outside the target. The thermal adjustment devices can be adjusted to operate at different capacities. The control of thermal adjustment devices is known to be rather difficult. Varying conditions easily cause over- or under-heating in them, which can lead to independent oscillation of the device or mutual oscillation of adjacent devices and to additional adjustments made by the user, which can make the situation worse. Additionally the thermal adjustment devices easily waste energy, for example in connection with ventilating a room, whereby the device may think that the temperature in the room has dropped and try to rectify the situation with excessive additional heating. The thermal adjustment system consists of several thermal adjustment devices and an apparatus controlling them.

The capacity of the thermal adjustment devices is controlled with a room adjuster via an actuator included therein or separate therefrom. The thermal adjustment device has a certain capacity range, which can be adjusted with the aid of the actuator. When the actuator is adjusted to its maximum point, the thermal adjustment device operates at its maximum capacity, and when the actuator is in its minimum point, the thermal adjustment device does not produce power. In thermal adjustment the room adjuster can have a heat sensor or a connection to a heat sensor, which measures the temperature of the target, which it is striven to adjust. The room adjuster can also be given a set temperature, where it is desired that the temperature of the target to be heated should settle. The room adjuster adjusts its operation so that the controllable thermal adjustment device operates so that the temperature of the target should be as close as possible to the given set temperature. The operation and structure of the room adjuster and actuator depend on the controllable thermal adjustment device and on the amount and complexity of the control automation. At its simplest the actuator is a valve motor, which is used to adjust the amount of heating substance getting into the thermal adjustment device. Figure 2 shows an example of a prior art arrangement for controlling an actuator. It has a room temperature sensor 201 , a room adjuster 202, an actuator 203 and a thermal adjustment device 204. The room adjuster measures the current temperature with the room temperature sensor and it is given some goal temperature, where it is desired for the temperature of the target to settle. Based on this information the room adjuster defines a control signal, with which it controls the actuator. The value and form of the control signal depend on the structure and operation of the actuator. The actuator controls the thermal adjustment device according to the received control signal. For example in electrically operated floor heating the heating is switched on, until the desired temperature is reached, whereby the supply of electricity to the resistor is stopped. Thereafter the temperature of the target is monitored, until it has dropped below the set temperature, whereby the heating is started again. Because the floor heating has delays, it is possible that the floor can cool down or heat up excessively.

Patent publication WO 2008/029987 discusses an automatic thermal adjustment method, where the target apartment or building is divided into temperature zones, the temperature of which is monitored with contact-free sensors. Each temperature zone can be given its own set temperature. Based on the results given by the sensors, the aim is to adjust the temperature of the temperature zones to the set temperature by controlling the heating and air-conditioning devices of the target. The aim has here however not been to manage the heating device, but it is very possible that it starts to oscillate, i.e. it first operates at its full capacity, whereby the temperature zone can overheat due to the heating delays, whereby the device is turned off, whereby the zone may have time to cool down. It is also possible that the heating and air-conditioning in this case start to operate in turn. This wastes energy and can be unpleasant for someone in the temperature zone in question.

Patent publication US 2005/0234596 describes a method, where the thermal adjustment of the target, such as the building, is controlled with the aid of external variables. As in the previous publication, the tendency of the thermal adjustment devices to oscillate is also here not taken into account. An object of the invention is a solution by which the drawbacks and disadvantages relating to the prior art can be considerably reduced.

The objects of the invention are obtained with a method and an apparatus, which are characterised in what is presented in the independent claims. Some advantageous embodiments of the invention are presented in the dependent claims.

The main idea of the invention is to set dynamic operating limits for the control of the thermal adjustment device of the target, by means of which limits the capacity range of the thermal adjustment device is scaled. Thus dynamic limits for the control are set also for the heat production, which limits change based on external variables, and a capacity range scaled by means of which limits is smaller than an unlimited capacity range of the thermal adjustment device. Thus unnecessary oscillation of the thermal adjustment device can for example be prevented.

In the method according to the invention the actuator of the thermal adjustment device is controlled in order to adjust the temperature in a target. For controlling the actuator there are three adjustment blocks: a first adjustment block, a second adjustment block and a third adjustment block. An adjustment block here means a functional entity, which concentrates on the adjustment of the operation of some specific area. The adjustment blocks can be implemented with different devices or combinations of devices or with programs functioning in devices or in a device.

Dynamic operating limits, at least a maximum and a minimum, are calculated in the method based on scaling constants and scaling variables. The dynamic operating limits change based on the scaling variables. For example when the outside temperature drops, the maximum of the dynamic operating limits can increase. The control signal is proportional to the set temperature, where it is desired for the temperature of the target or of a part of it to settle. The dynamic operating limits and the control signal are read in the method and an output signal is calculated for controlling the actuator by scaling the control signal with the dynamic operating limits, and the actuator, which controls the thermal adjustment device, is controlled based on the output signal. The output signal can thus vary from the minimum of the dynamic operating limit to the maximum of the dynamic operating limit.

In one embodiment of the method according to the invention the scaling constants in the memory of the first adjustment block are defined based on the structures and dimensions of the target. Factors affecting the scaling constants are for example the size of windows, the surface area of cooling surfaces, the material of the structures, the heat leakage constants of the structures, thermal conduction delays and the dimensioning of the heating capacity. In a second embodiment of the method according to the invention the scaling variables are at least some of the following: the outside temperature of the target, where the thermal adjustment device is; wind conditions, such as speed and direction; cloudiness; outside humidity; inside humidity; air pressure; presence of residents in the target; time; the structural constant altered by the outside conditions and forecasts for said adjustment variables.

In a third embodiment of the method according to the invention the target has several parts and each part has its own control signal. A set temperature is given to the part of the target, which is the temperature, where it is desired for the temperature of the part of the target to settle. The temperature of the target is further measured. The control signal is calculated based on the set temperature and the measured temperature.

In a fourth embodiment of the method according to the invention a diagram formed at least by the maximum of the dynamic operating limit and the minimum of the dynamic operating limit is used in scaling the control signal, in which diagram the maximum value of the control signal gives the output signal a maximum dynamic operating limit and the minimum value of the control signal gives the output signal a minimum dynamic operating limit, and the values between the maximum and minimum values of the control give the output signal a value corresponding thereto in the diagram. In a fifth embodiment of the method according to the invention the diagram is linear. In a sixth embodiment of the method according to the invention the diagram is nonlinear. Thus, when calculating the dynamic operating limits, the points between the dynamic maximum and dynamic minimum are also calculated and the diagram is made with the aid of these points. The diagram can also be interpolated with some equation or algorithm.

An apparatus according to the invention for controlling an actuator of a thermal adjustment device in order to adjust the temperature in a target has three adjustment blocks: a first adjustment block, a second adjustment block and a third adjustment block. The adjustment blocks are operational units, which are included in a thermal arrangement system. They can be included in the thermal adjustment system as independent devices or they operate in already completed parts of the thermal adjustment system, such as in its central and control units and other devices. At least some of the functions of the adjustment blocks can be implemented as command sequences executed in the processors of the devices in the thermal adjustment system.

The first adjustment block has at least a memory, a processor, means for receiving and sending information. In the memory of the first adjustment block there are scaling constants, which have been stored for example during calibration or start-up of the apparatus. The scaling constants can when necessary be changed, but generally they remain constant. The scaling variables are read into the first adjustment block. This can be done automatically, but at least some can be entered manually. The processor of the first adjustment block calculates the dynamic operating limits, the maximum and the minimum, based on the scaling variables and scaling constants. The second adjustment block has at least a memory, a processor, means for receiving and sending information, and the second adjustment block is arranged to produce a control signal value and to store it in the memory, when necessary. This control signal is proportional to the temperature of the target and the set value of the temperature, where it is desired for the temperature of the target to settle. The third adjustment block has at least a memory, a processor, means for receiving and sending information, and the third adjustment block is arranged to read the dynamic operating limits from the first adjustment block and the control signal from the second adjustment block and to calculate an output signal for controlling the actuator by scaling the control signal with the dynamic operating limits and to control the actuator, which controls the thermal adjustment device, with the aid of the output signal.

In an embodiment of the apparatus according to the invention the scaling constants in the memory of the first adjustment block are stored during calibration or start-up of the apparatus and are defined based on the structures or dimensions. Factors affecting the scaling constants are for example the size of windows, the surface area of cooling surfaces, the material of the structures, thermal conduction delays of the structures and the dimensioning of the heating capacity.

In a second embodiment of the apparatus according to the invention the scaling variables of the first adjustment block are arranged to be read or entered from outside the adjustment block and the scaling variables are at least some of the following: the outside temperature of the target, where the thermal adjustment device is; wind conditions, such as speed and direction; cloudiness; outside humidity; inside humidity; air pressure; presence of residents in the target; time and forecasts for said adjustment variables. In a third embodiment of the apparatus according to the invention the target has several parts and each part has its own second adjustment block, which has the means to arrange the set value of the temperature to be written or read from outside the adjustment block. The second adjustment block is also arranged to read the temperature or temperatures of the part of the target. In a fourth embodiment of the apparatus according to the invention the output signal is arranged to control the actuator, which controls the thermal adjustment device, and the controllable variables of the thermal adjustment device are at least one of the following: heating capacity, pulse length, time between pulses, valve position, liquid flow rate or a combination of the above-mentioned. In a fifth embodiment of the apparatus according to the invention the first adjustment block is shared by the entire target or at least by some parts of the target. Thus the first adjustment block can for example be in the central unit controlling the apparatus, which central unit is a computer or a corresponding device. In a sixth embodiment of the apparatus according to the invention the third adjustment block is shared by at least some parts of the target. Thus the same adjustment block can control several thermal adjustment devices simultaneously or in turn. The third adjustment block can be in the same device as the first adjustment block. Thus the first adjustment block and the third adjustment block can use the same processors and memories. In a seventh embodiment of the apparatus according to the invention at least some of the adjustment blocks or functions of the adjustment blocks can be implemented in the same device. This device can be a computer or a embedded system.

In an eighth embodiment of the apparatus according to the invention at least some of the functions of the blocks can be implemented as algorithms, which are stored in the memory and executed in the processor. This memory and processor can be situated in the central unit or in another device controlling the operation of the apparatus. In the computer program product according to the invention for controlling an actuator of a thermal adjustment device when adjusting temperature, running the computer program product stored in the memory of the thermal adjustment system in its processor provides the following kinds of operations. Scaling variables are read from an external source and scaling constants are read from the memory, and dynamic operating limits are calculated, at least a maximum and a minimum, based on the scaling constants and scaling variables. The value of the control signal is read. An output signal is calculated by scaling the control signal with the dynamic operating limits and the actuator, which controls the thermal adjustment device, is controlled based on the output signal.

It is an advantage of the invention that it provides energy efficiency, when unnecessary heating and cooling can be avoided. It also easily provides precise, quick and stable adjustment. The invention is also simple, whereby it can be used in small capacity devices. It is further an advantage of the invention that it makes the temperature remain more even, whereby comfort is increased.

It is further an advantage of the invention that it can be used to improve the functionality of slow responding heating methods, such as floor heating.

It is also an advantage of the invention that it can be adapted for different heating methods and devices.

It is an advantage of the invention that it makes possible the managing of a heating system in quickly changing situations and it can prevent possible malfunctions.

In the following, the invention will be described in detail. In the description, reference is made to the appended drawings, in which

Figure 1 shows as an example a flow chart of a method according to the invention,

Figure 2 shows adjustment according to prior art,

Figure 3 shows as an example adjustment blocks according to the invention, Figure 4a and b shows as an example dynamic operating limits according to the invention as a function of the outside temperature and Figure 5 shows as an example a diagram of the scaling of the output signal according to the invention.

Figure 1 shows as an example a flowchart of the method according to the invention. In step 101 the controlling of the actuator of the thermal adjustment device is started. In step 102 the scaling variables are read. These can be read automatically, such as for example the outside temperature, the air pressure and the wind speed, or they can be entered manually, such as for example forecasts or utilisation rate of the target. The manual entering can be done for example with a computer or with a text message or with a managing device of the thermal adjustment system. In connection with the reading of the scaling variables, the scaling constants are read from the memory. Some scaling variables can be seen as scaling constants, such as for example the number of residents in the target, and it can be changed only when necessary.

In step 103 dynamic operating limits are calculated based on the scaling variables and scaling constants. Dynamic here means that as the variables change, the operating limits also change. Pre-stored equations based on the scaling variables and scaling constants are used in the operating limit calculations. The operating limits have at least a maximum Dmax and a minimum Dmin. At its simplest only a maximum value is calculated and the minimum is kept constant. In some cases more values can be calculated. The operating limit values can advantageously be presented as percentages or ratios. Thus they illustrate the magnitude of the control of the thermal adjustment, where 100% means that the thermal adjustment device is operating at its full capacity, 0% means that it is not producing power at all, and for example 50% naturally means that the capacity is half of what it could be.

In step 104 the points of the dynamic operating limits are used to form a scaling diagram. The scaling diagram is usually linear, but nonlinear scaling diagrams can also be used, whereby the scaling diagram can for example be a combination of several angular coefficient lines. On one axis of the scaling diagram is the control signal and on the other axis is the output signal.

In step 105 the control signal is read.

In step 106 the control signal is scaled with the scaling diagram into an output signal. The value of the control signal is placed on the control signal axis and the corresponding value of the output signal is read from the output signal axis in the scaling diagram.

In step 107 the actuator, which controls the thermal adjustment device, is controlled based on the output signal. In step 108 the use of the method is ended. In use, the scaling activity according to the invention can be repeated for example at certain intervals or if scaling variables or scaling constants have been changed in some part of the target or if other changes are observed.

Figure 3 shows an example of a thermal adjustment arrangement according to the invention. It consists of a temperature sensor 301 , a first adjustment block 304, a second adjustment block 302, a third adjustment block 305, an actuator 303 and a thermal adjustment device 306. For the sake of clarity only one part of the target is shown here. In a target, which has several parts, each part can have its own room adjuster. The setting of the temperature of the room adjusters can also be done in a centralised manner. Each part of the target has its own actuator and thermal adjustment device.

In Figure 3 the temperature sensor 301 , the first adjustment block 304, the second adjustment block 302, the third adjustment block 305, the actuator 303 and the thermal adjustment device 306 are in some part, such as a room, of the target, the temperature of which is being adjusted, such as a building. The first adjustment block 304 defines the dynamic operating limits of the control and it can give these limits to several similar entities. The first adjustment block has at least a memory, a processor and means for receiving and sending information. The first adjustment block has stored in its memory the scaling constants and it can read the scaling variables it needs either automatically or manually entered or as a combination thereof. Based on the scaling constants and scaling variables it calculates the dynamic operating limits. The operating limits are calculated with an algorithm suited for each target and situation, which algorithm is stored in the first adjustment block. Different operating limits are defined for different types of thermal adjustment devices. For example an electrically operated floor heating receives different operating limits than a radiator heating with liquid circulation, even if the scaling variables are the same, because their conduct in the heating process is different. The temperature of the part of the target is measured with the temperature sensor 301. The second adjustment block 302 has at least a memory, a processor, means for receiving and sending information. The second adjustment block calculates a value for the control signal based on the temperature measured from the target and the desired temperature value of the target. For example when the difference between the set temperature and the temperature measured in a part of the target changes, the control signal also changes. Algorithms stored in the memory are used for calculating the control signal.

The third adjustment block 305 has at least a memory, a processor and means for receiving and sending information. It reads the dynamic operating limits from the first adjustment block 304 and from the second adjustment block it reads the control signal produced thereby. In the third adjustment block the control signal produced by the second adjustment block is scaled with the dynamic operating limits, whereby an output signal is obtained. This is done by forming a scaling diagram in the coordinates, where the control signal is on one axis and the output signal is on the other axis. An output signal, which is scaled with the dynamic operating limits, is received with the aid of the scaling diagram. The output signal is used to control the actuator 303, which controls the thermal adjustment device 306. The adjustment blocks can also be divided in other ways. Above the adjustment blocks were each their own device, but for example the second adjustment block, the third adjustment block and the actuator can be in the same device, or for example the second adjustment block and the temperature sensor are in the same device, or the third adjustment block or a part thereof is implemented in the same device as the first adjustment block. There can also be a solution, where all the adjustment blocks are in the same device, which controls the actuators of the different parts of the target.

Figure 4 shows an example of the definition of the dynamic operating limits as a function of the outside temperature, i.e. the outside temperature is the scaling variable. The outside temperature is on the X axis and the operating limit is on the Y axis. Figure 4(a) shows a diagram, which is used to define the maximum value of the dynamic operating limit, and Figure 4(b) shows a diagram, which is used to define the minimum value of the dynamic operating limit. The diagrams illustrate some algorithms, which are implemented in the first adjustment block. The scaling constants affect the shape of the diagrams. When the outside temperature is 20 °C, the diagram in Figure 4(a) gives the maximum value of the dynamic operating limit Dmax as 30% and the diagram in Figure 4(b) the minimum value of the dynamic operating limit Dmin as 10%. In the same way, when the outside temperature is 0 °C, the maximum value of the dynamic operating limit Dmax is given as 60% and the minimum value of the dynamic operating limit Dmin as 25%. When the outside temperature is -20 °C, the maximum value of the dynamic operating limit Dmax is given as 90% and the minimum value of the dynamic operating limit Dmin as 40%. The values of the operating limits can be given as percentages or ratios, but other values can also be used. These operating limits form the operating range window.

It should be noted that for the sake of clarity, the example described above has only one scaling variable. Different definition diagrams are used in the case of several scaling variables. It is also possible that its own dynamic operating limits are defined for each scaling variable and they are combined with some mathematical method, for example using weighting coefficients, i.e. the most important scaling variables are given a higher weighting coefficient.

Figure 5 shows an example of the scaling of an output signal according to the invention from the control signal. The maximum and minimum of the dynamic operating limits are given here, as was done in Figure 4. Now for example the outside temperature is -15 °C and additionally six persons are staying in the target. With these scaling variables the maximum value of the dynamic operating limit Dmax is given as 80% and the minimum value of the dynamic operating limit Dmin as 25%. Said maximum and minimum values of the dynamic operating limit are placed in the coordinates, where the control signal is on the X axis and the output signal is on the Y axis. The minimum value is placed at the minimum of the control signal, i.e. in the point (0%, Dmin) and the maximum value in (100%, Dmax). In this case the points (0%, 25%) and (100%, 80%) are obtained. A straight line is drawn through these points.

When a control signal is obtained, which is formed based on the set temperature and measured temperature of the target, the temperature of which is adjusted, it is scaled with the aid of the diagram in Figure 5. For example the room adjuster has been used to give a set temperature of 25 °C and the measured temperature is 20 °C, whereby the control signal is calculated as 100%. When scaling, the 100% control signal becomes an 80% output signal. In a second example the room adjuster has been used to give a set temperature of 20 °C and the measured temperature is 18 °C, whereby the control signal is calculated as 50%. When scaling this control signal, it becomes an output signal, the value of which is 55%. In a third example the room adjuster has been used to give a set temperature of 19 °C and the measured temperature is 23 °C, whereby the control signal is calculated as 0%. When scaling this control signal, it becomes an output signal, the value of which is 25%. Especially from this example it can easily be seen that with this invention, the effect of the control signal on the heating adjustment is always proportioned to the actual need according to different conditions, whereby the control signal itself can easily be used to produce a precise, quick and stable adjustment. Especially from this example it can easily be seen how with the aid of the invention, an uncomfortable situation can be avoided in the winter, where the heating logic stops the heating, whereby the room and the structures may have time to cool down before the heating can again catch up.

It should be noted that the control and output signals can also be some other values than percentages. They can for example be voltages or pulses or the like. Some advantageous embodiments according to the invention have been described above. The invention is not limited to the solutions described above, but the inventive idea can be applied in numerous ways within the scope of the claims.

Claims

1 . A method for controlling an actuator of a thermal adjustment device when adjusting temperature in a target, which actuator has a capacity range, which has a maximum and a minimum, characterised in that the method has the following steps:

- calculating dynamic operating limits (103), at least a maximum and a minimum, based on scaling constants and scaling variables, the capacity range scaled with the aid of which limits is smaller than an unlimited capacity range of the thermal adjustment device

- defining a control signal

- calculating an output signal for controlling the actuator by scaling the control signal with the dynamic operating limits (106) and

- controlling the actuator of the thermal adjustment device with the output signal (107).

2. The method according to claim 1 , characterised in that factors affecting the scaling constants are structural constants of the target, which are for example size of windows, surface area of cooling surfaces, material of the structures, heat leakage constants of the structures, thermal conduction delays and dimensioning of the heating capacity.

3. The method according to claim 1 or 2, characterised in that scaling variables are at least some of the following: outside temperature of the target, where the thermal adjustment device is; wind conditions, such as speed and direction; cloudiness; outside humidity; inside humidity; air pressure; presence of residents in the target; time; the structural constant altered by the outside conditions and forecasts for said adjustment variables.

4. The method according to any of the claims 1-3, characterised in that the target has several parts and each part has its own control signal and the control signal is calculated based on the set temperature and the measured temperature of the part of the target.

5. The method according to any of the claims 1-4, characterised in that a diagram formed at least by the maximum of the dynamic operating limit and the minimum of the dynamic operating limit is used in scaling (106) the control signal, in which diagram the maximum value of the control signal gives an output signal a maximum dynamic operating limit and the minimum value of the control signal gives the output signal a minimum dynamic operating limit, and the values between the maximum and minimum values of the control give the output signal a value corresponding thereto in the diagram.

6. The method according to claim 5, characterised in that the diagram is linear.

7. The method according to claim 5, characterised in that the diagram is nonlinear, whereby, when calculating (103) the dynamic operating limits, points between the dynamic maximum and dynamic minimum are also calculated and the diagram is made with the aid of these points.

8. An apparatus for controlling an actuator (303) of a thermal adjustment device (306) when adjusting temperature in a target, which actuator has a capacity range, which has a maximum and a minimum, characterised in that the control of the actuator includes three adjustment blocks: a first adjustment block (304), a second adjustment block (302) and a third adjustment block (305), and

- the first adjustment block has at least a memory, a processor and means for receiving and sending information, and

- the memory has scaling constants, and scaling variables are arranged to be read into the memory

- the processor is arranged to calculate dynamic operating limits, at least a maximum and a minimum, based on the scaling constants and scaling variables, the capacity range scaled with the aid of which limits is smaller than an unlimited capacity range of the thermal adjustment device

- the second adjustment block has at least a memory, a processor and means for receiving and sending information, and the second adjustment block is arranged to produce a control signal based on a received set temperature and measured temperature and

- the third adjustment block has at least a memory, a processor and means for receiving and sending information, and the third adjustment block is arranged to read the dynamic operating limits from the first adjustment block and the control signal from the second adjustment block and to calculate an output signal for controlling the actuator by scaling the control signal with the dynamic operating limits and to control the actuator according to the output signal.

9. The apparatus according to claim 8, characterised in that the scaling constants in the memory of the first adjustment block (304) have been stored during start-up of the apparatus and factors affecting the scaling constants are structural constants of the target, which are for example size of windows, surface area of cooling surfaces, the material of the structures, thermal conduction delays of the structures and dimensioning of the heating capacity.

10. The apparatus according to any of the claims 8 or 9, characterised in that the scaling constants of the first adjustment block (304) are arranged to be read or entered from outside the adjustment block and the adjustment variables are at least some of the following: the outside temperature of the target, where the thermal adjustment device (306) is; wind conditions, such as speed and direction; cloudiness; outside humidity; inside humidity; air pressure; presence of residents in the target; time and forecasts for said adjustment variables.

1 1. The apparatus according to any of the claims 8-10, characterised in that the target has several parts and each part has its own second adjustment block (302) and each second adjustment block has means for arranging the set temperature value to be written or read from outside the adjustment block, and the second adjustment block is arranged to read the temperature or temperatures from the part of the target.

12. The apparatus according to any of the claims 8-11 , characterised in that the output signal is arranged to control the actuator (303), which controls the thermal adjustment device (306), and controllable quantities of the thermal adjustment device are at least one of the following: heating capacity, pulse length, time between pulses, valve position, liquid flow rate or a combination of the above- mentioned.

13. The apparatus according to any of the claims 8-12, characterised in that the first adjustment block (304) is shared by the entire target or at least some parts of the target.

14. The apparatus according to any of the claims 8-13, characterised in that the third adjustment block (305) is shared by at least some parts of the target.

15. The apparatus according to any of the claims 8-14, characterised in that at least some of the adjustment blocks and functions of the adjustment blocks can be implemented in the same device.

16. The apparatus according to any of the claims 8-15, characterised in that at least some of the functions of the adjustment blocks can be implemented as algorithms, which are stored in the memory and executed in a processor.

17. A computer program product for controlling an actuator of a thermal adjustment device when adjusting temperature, which actuator has a capacity range, which has a maximum and a minimum, characterised in that running the computer program product provides the following functions:

- reading of scaling variables from an outside source and reading of scaling constants from a memory, and calculation of dynamic operating limits, at least a maximum and a minimum, based on the scaling constants and scaling variables, a capacity range scaled with the aid of which limits is smaller than an unlimited capacity range of the thermal adjustment device

- reading the value of a control signal and

- calculating an output signal by scaling the control signal with the dynamic operating limits and controlling the actuator, which controls the thermal adjustment device, based on the output signal.