DE102014201618A1 - heating system - Google Patents

Abstract

A heating system having at least one heat generator unit (12a, 12b), at least one exhaust pipe (14a, 14b), at least one fan (16a, 16b) for generating a gas flow (18a, 18b) within the at least one exhaust pipe (14a, 14b) with a sensor unit (20a, 20b) which is provided in a measuring operating state for detecting at least one flow characteristic value of the gas flow (18a, 18b). It is proposed that the heating system comprises a test unit (22a, 22b) which is provided, in a test operating state for a functional check of the sensor unit (20a, 20b), at least one input variable of the sensor unit (20a, 20b) in at least one test step is different from deactivating the at least one blower (16a, 16b).

Description

State of the art

The invention relates to a heating system according to the preamble of patent claim 1 and a method for operating a heating system according to the preamble of patent claim 10.

A heating system with at least one heat generator unit has already been proposed which has at least one exhaust pipe, at least one fan for generating a gas flow within the at least one exhaust pipe and a sensor unit, the sensor unit being provided in a measuring operating state for detecting at least one flow characteristic of the gas flow , In this case, ambient conditions, such as a wind occurring, which acts in particular sucking on the at least one exhaust pipe, lead to a functional control of the sensor unit is falsified and thus results of the function control are useless.

Disclosure of the invention

The invention is based on a heating system with at least one heat generator unit, with at least one exhaust pipe, with at least one fan for generating a gas flow within the at least one exhaust pipe and with a sensor unit which is provided in a measurement operating state for detecting at least one flow characteristic of the gas flow.

It is proposed that the heating system has a test unit which is provided, in a test operating state for a functional check of the sensor unit, at least one input variable of the sensor unit in at least one test step, which consists of deactivating the at least one blower and in particular also reading out and / or evaluating an output signal of the sensor unit differs to change.

A "heating system" is to be understood, in particular, as a system which is provided in particular for installation within a building and which is intended to generate and / or store and / or distribute thermal energy, preferably for heating premises. In particular, the heating system can be provided for heating and / or storage and / or distribution of drinking and / or service water and / or for supplying at least one heating circuit. By "provided" is intended to be understood in particular specially programmed, designed and / or equipped. The fact that an object is intended for a specific function should in particular mean that the object fulfills and / or executes this specific function in at least one application and / or operating state. In this context, a "heat generator unit" is to be understood as meaning in particular a unit which is intended to generate thermal energy and / or in particular by using at least one energy carrier and / or by a particular chemical reaction and / or by solar energy, in particular solar thermal energy to make usable. In this case, the heat generator unit preferably has a heat output of at least 0.1 kW, in particular of at least 0.5 kW, preferably of at least 2 kW and particularly advantageously of at least 5 kW.

In this context, an "exhaust pipe" should be understood in particular to mean a hollow pipe, in particular a pipe, which is intended to remove a gas, in particular an exhaust gas and / or preferably a purge gas, in particular purge air, from the at least one heat generator unit. In particular, the at least one exhaust pipe connects a process space of the at least one heat generator unit and / or preferably an installation space, in which the at least one heat generator unit is arranged, with an outer area of a building within which the heating system is installed. In particular, a particular continuous transport of the exhaust gas along the exhaust pipe is at least partially ensured by the at least one fan, which generates in at least one operating state directed by the at least one heat generator unit in the direction of the exterior of the building gas flow within the at least one exhaust pipe. In this context, a "waste gas" is to be understood as meaning, in particular, a waste product which arises during a material conversion process and which is at least substantially gaseous. In this context, a "purge gas" is to be understood as meaning, in particular, a gas, in particular non-flammable and / or non-toxic gas, which is provided to surround flammable gas and / or potentially toxic exhaust gas leading elements of a heat generator unit. In this context, a "scavenging air" is to be understood as meaning, in particular, ambient air, which is supplied to a housing of the at least one heat generator unit via at least one supply air line and, in particular, preferably surrounds all elements of a combustible gas unit carrying at least one combustible gas and / or toxic exhaust gas. In particular, the scavenging air is intended to dilute in particular due to leaks escaping combustible gas and / or toxic exhaust gas and thus to avoid formation of an explosive mixture and / or a risk of poisoning. The purging air is in particular at least partially removed together with the exhaust gas of the at least one heat generator unit via the at least one exhaust gas line.

In this context, a "sensor unit" is to be understood as meaning, in particular, a unit which is intended to quantitatively record, in particular, physical and / or chemical properties and / or the material quality of its environment qualitatively and / or as a measured variable. In this context, a "flow characteristic" is to be understood as meaning, in particular, a characteristic value which contains at least information about a flow, in particular about a gas flow within the at least one exhaust gas line and / or at least one supply air line. In particular, the at least one flow characteristic may contain at least one information which reflects a presence of the gas flow and / or a flow velocity of the gas flow. The at least one flow characteristic may be designed in particular as a volume, mass and / or particle flow value. The at least one flow characteristic is preferably at least one pressure, in particular a differential pressure. In particular, a detection of the at least one flow characteristic can be carried out continuously and / or in, in particular fixed, time intervals.

In this context, a "test unit" is to be understood as meaning in particular a unit which is intended to carry out a check of the at least one sensor unit for an error-free function, in particular due to a manual actuation and / or semi-automatic and / or preferably fully automatic. Preferably, a functional check of the sensor unit takes place in particular specified time intervals. A functional check of the sensor unit can be carried out in particular in one or more test steps, which can be executed successively and / or at least partially simultaneously by the test unit. A "testing step" is to be understood, in particular, as a process step which is necessary for carrying out a function check within the test operating state. In particular, the test unit is provided to execute at least one test step within the test operating state, within which an input variable of the sensor unit is changed such that a detectable change of an output variable of the sensor unit results therefrom. In this context, an "input variable of the sensor unit" should be understood to mean, in particular, a measured variable detected by the sensor unit, which can be further processed and / or evaluated by the sensor unit. In particular, the sensor unit converts the at least one input variable into an analog and / or digital output value.

Such a configuration can provide a heating system with advantageous properties with regard to a functional check of a sensor unit which is provided for monitoring a gas flow generated by at least one blower within at least one exhaust gas line and / or one supply air line. In particular, a reliability of a function control can advantageously be increased, whereby a falsifying influence of ambient conditions, for example occurring wind, can at least largely be ruled out. Furthermore, a functional check can be carried out independently of a deactivation of the at least one blower, which advantageously makes it possible to operate the heating system at least substantially uninterrupted.

It is also proposed that the sensor unit comprises a sensor element, which is provided in the measurement operating state, in the case of exceeding a first particular limit by the at least one flow characteristic a first particular set output value and in case of falling below a second particular set limit by the at least one flow characteristic to output a second particular set output value. In particular, the first limit value can be identical to the second limit value. In particular, the limit values can be stored in a memory unit of the sensor unit. In particular, in the measuring operating state, a preferably continuous comparison of the flow characteristic value with the especially stored limit values takes place. As a result, overshooting and / or undershooting a limit value can advantageously be detected simply on the basis of the output value and / or a change in the output value of the sensor unit.

Furthermore, it is proposed that the sensor unit has at least one pressure sensor which is provided to detect a pressure difference within the at least one exhaust gas line. In this context, a "pressure sensor" should be understood as meaning, in particular, a sensor which detects at least two absolute pressures and / or compares them with one another and / or detects a pressure difference. In particular, the pressure sensor is provided to detect the at least two absolute pressures at at least two measuring points, which are arranged along the course of the at least one exhaust pipe spaced from each other. In particular, detection takes place via at least two measuring sensors, which each have at least one measuring opening. In particular, at least one measuring opening of at least one first measuring sensor is aligned counter to a flow direction of the gas flow, while at least one measuring opening of at least one second measuring sensor is aligned in the flow direction of the gas flow, so that a static and / or a dynamic pressure can be detected. In particular, the at least one pressure sensor is provided to detect a pressure difference between the at least two measuring points caused by the gas flow. As a result, a flow characteristic of the gas flow can advantageously be detected simply and / or reliably in the measuring operating state. In particular, advantageously, a presence of the gas flow can be detected and / or a flow velocity and / or direction of the gas flow can be determined.

It is also proposed that the at least one test unit comprises a bridging unit which is provided to short-circuit at least two inputs of the at least one pressure sensor during the test operating state. In this context, a "bridging unit" should be understood as meaning, in particular, a unit which is provided to establish a fluidic connection between at least two inputs of the at least one pressure sensor in the test operating state. In particular, the at least two inputs of the at least one pressure sensor are connected to one another during the test operating state by the bridging unit such that between the at least two inputs of the at least one pressure sensor a pressure difference of at most 20 Pa, advantageously of at most 10 Pa, particularly advantageously of at most 5 Pa and preferably sets at most 2 Pa. As a result, an input variable of the sensor unit can advantageously be changed.

If the bridging unit has at least one valve, an advantageously simple and / or reliable short-circuiting of at least two inputs of the at least one pressure sensor can take place. In particular, the at least one valve can be designed as a manually operated valve and / or as an electromotively actuated valve and / or as an electromagnetically actuated valve and / or as a medium-actuated valve.

In particular, it is conceivable that the at least one valve and the at least one fan can be controlled independently of one another by the test unit. However, the test unit is advantageously provided in the test operating state to jointly control the at least one valve and the at least one fan. In particular, a control of the at least one valve may be coupled directly to a control of the at least one fan and / or carried out via a common control path, whereby the at least one valve and the at least one fan at the same time or offset in time by the test unit can be controlled. In this way, an advantageously simple and / or cost-effective control of the at least one valve and the at least one fan can be realized.

Advantageously, the test unit is provided in Prüfbetriebszustand to open the at least one valve and disable the at least one fan, whereby an input of the sensor unit can be changed in an advantageously significant extent.

If the test unit is provided in the test operating state to reverse a conveying direction of the at least one blower, in particular with respect to a conveying direction of the at least one blower in the measurement operating state, a particularly significant reduction and / or reversal of the gas flow within the exhaust pipe can be achieved, thereby advantageously simple a change of the at least one input variable of the sensor unit can be made.

Furthermore, it is proposed that the at least one heat generator unit is designed as a fuel cell unit and that at least one exhaust pipe is provided to dissipate at least part of a purge air. In this context, a "fuel cell unit" is to be understood as meaning, in particular, a unit for stationary and / or mobile extraction, in particular electrical and / or thermal energy, using at least one fuel cell, which is provided with at least one chemical reaction energy of at least one, in particular continuously supplied, fuel gas , in particular natural gas, methane, hydrogen and / or carbon monoxide, and at least one oxidizing agent, in particular air and / or oxygen, in particular into electrical and / or thermal energy to understand understood. The at least one fuel cell can be designed in particular as a solid oxide fuel cell (SOFC). Preferably, the at least one fuel cell unit comprises a plurality of fuel cells, which are arranged in particular in a fuel cell stack. In this way, advantageously, a fuel cell unit can be integrated as a heat generator unit in a heating system.

Furthermore, a method for operating a heating system with at least one heat generator unit, with at least one exhaust pipe, with at least one fan for generating a gas flow within the at least one exhaust pipe and with a sensor unit, which in a measurement operating state to a detection at least a flow characteristic of the gas flow is provided, wherein in a test operating state to a functional control of the sensor unit at least one input measured variable of the sensor unit in at least one test step, which is different from deactivating the at least one blower, is changed. In this way, a functional control of the at least one sensor unit can be made possible in a simple manner.

The heating system according to the invention should not be limited to the application and embodiment described above. In particular, in order to fulfill a mode of operation described herein, the heating system according to the invention can have a number deviating from a number of individual elements, components and units mentioned herein.

drawing

Further advantages emerge from the following description of the drawing. In the drawing, two embodiments of the invention are shown. The drawing, the description and the claims contain numerous features in combination. The person skilled in the art will expediently also consider the features individually and combine them into meaningful further combinations.

Show it:

1 a heating system with a heat generator unit, with an exhaust pipe, with at least one fan for generating a gas flow within the exhaust pipe, and with a sensor unit and a test unit, which has a bridging unit,

2 a circuit variant for jointly controlling a fan and a valve by the test unit of the heating system 1 .

3 an alternative circuit variant for jointly controlling a fan and a valve by the test unit of the heating system 1 and

4 an alternative embodiment of a heating system with a heat generator unit, with an exhaust pipe, with at least one fan for generating a gas flow within the exhaust pipe, and with a sensor unit and a test unit, which is intended to reverse a conveying direction of the blower.

Description of the embodiments

1 shows a heating system 10a with a heat generator unit shown here only schematically 12a , The heat generator unit 12a is as a fuel cell unit 38a with a fuel cell stack shown here indicated 42a educated. The heat generator unit 12a is preferably operated in a known manner with natural gas from a natural gas network, not shown here. Furthermore, the heating system 10a an exhaust pipe 14a on, about which exhaust gases of the heat generator unit 12a be dissipated. The exhaust pipe 14a connects an airspace 48a the heat generator unit 12a within which the fuel cell stack 42a is arranged, with an outdoor area 50a a building, of which here only a roof 44a and an outer wall 46a within which are the heating system 10a is set up. To ensure a continuous transport of the exhaust gas along the exhaust pipe 14a indicates the heating system 10a a fan 16a on which during a heating system operation 10a one from the heat generator unit 12a in the direction of the outside area 50a of the building directed gas flow 18a inside the exhaust pipe 14a generated. The exhaust pipe 14a ends, for example, as shown here above the roof 44a , Via an air supply line 52a becomes the heat generator unit 12a Supplied ambient air. The supplied ambient air is both process air for the fuel cell stack 42a as well as purge air used. The purge air preferably flows around all components of the heat generator unit that conduct a combustible gas 12a in particular in order to dilute flammable gas escaping due to any leaks and thus to avoid formation of an explosive mixture. The portion of the supplied ambient air used as purge air is also via the exhaust pipe 14a dissipated. The supply air line 52a Here is an example by an outer wall 46a guided, alternatively, however, would also be conceivable to lead a supply air duct through a roof of a building or to use air from the installation room.

For monitoring the exhaust gas removal from the heat generator unit 12a and / or the effectiveness of the purge air supply, the heating system further comprises a sensor unit 20a , which preferably continuously a flow characteristic of the gas flow 18a detected. For this purpose, the sensor unit 20a as a pressure sensor 26a trained sensor element 24a on. The pressure sensor 26a is intended to be a through the gas flow 18a caused pressure difference 28a between two measuring points 58a . 60a , which along the course of the at least one exhaust pipe 14a spaced and oppositely oriented to each other are arranged to determine. Alternatively, it is conceivable to arrange measuring points in an air supply line of ambient air and to monitor only an effectiveness of a scavenging air supply. Based on the pressure difference 28a may be a qualitative and / or quantitative assessment of gas flow 18a respectively. Preferably, the sensor element 24a such that, when the pressure difference is exceeded, a defined limit value is exceeded 28a a first output value and below the set limit value of the pressure difference 28a outputs a second output value. In particular, when falling below the limit, it must be assumed that there is no sufficiently strong gas flow 18a is present, whereupon the heating system 10a could be switched off safely.

To safely switch off the heating system 10a In case of failure, to be able to guarantee at any time, it is necessary, the function of the sensor unit 20a at regular intervals, for example every 24 hours. For this purpose, the heating system includes 10a a test unit 22a , The test unit 22a is intended during a functional test of the sensor unit 20a an input of the sensor unit 20a changed so that it results in a detectable change in the output value of the sensor unit 20a , in particular a switching from the first output value to the second output value or from the second output value to the first output value, results. In order to bring about a change in the input variable, the test unit has 22a a bridging unit 30a with a valve 36a on. The valve 36a is between two entrances 32a . 34a of the pressure sensor 26a arranged. During a functional check of the sensor unit 20a becomes the valve 36a through the test unit 22a open, eliminating the two inputs 32a . 34a be connected to each other. The connection established prevails at both inputs 32a . 34a an at least substantially identical pressure level, whereby a change in the output value of the sensor unit 20a is caused. If a change in the output value does not occur, this is due to a malfunction of the sensor unit 20a go out and the heating system 10a must be switched off. In addition to opening the valve 36a can also use the blower 16a through the test unit 22a be controlled. So can during the function control in addition to opening the valve 36a a deactivation of the blower 16a through the test unit 22a respectively.

The 2 and 3 show circuit variants, which is a common control of the fan 16a with the valve 36a enable. At the in 2 variant shown is the valve 36a parallel to the blower 16a connected. The valve 36a As shown, a hysteresis circuit 62a upstream, to reliably close the valve even at low fan supply voltage 36a to reach. At the in 3 variant shown is a control of the valve 36a via a relay 64a which is parallel to the fan 16a is switched. The relay 64a can turn a hysteresis circuit 62a be upstream.

Advantage of this type of function control over a pure deactivation of the blower 16a lies in insensitivity to environmental conditions. For example, an occurring wind 68a a pull in the exhaust pipe 14a produce. Includes the heating system 10a as shown, a second heat generator unit 40a For example, thermal convection may generate a suction effect. So would due to the ambient conditions even with the fan off 16a a pressure difference 28a through the sensor unit 20a detected, which would lead to incorrect results of the functional control. The negative influence on the functional control by environmental conditions is made by using the bridging unit 30a at least substantially eliminated completely.

In the 4 a further embodiment of the invention is shown. The following descriptions and the drawings are essentially limited to the differences between the exemplary embodiments, with reference in principle to the same reference components, in particular with respect to components with the same reference numerals, to the drawings and / or the description of the other embodiments, in particular 1 , can be referenced. To distinguish the embodiments of the letter a is the reference numerals of the embodiment in the 1 to 3 readjusted. In the embodiments of the 4 the letter a is replaced by the letter b.

4 shows a heating system 10b with a heat generator unit shown here only schematically 12b , The heat generator unit 12b is as a fuel cell unit 38b with a fuel cell stack shown here indicated 42b educated. The heat generator unit 12b is preferably operated in a known manner with natural gas from a natural gas network, not shown here. Furthermore, the heating system 10b an exhaust pipe 14b on, about which exhaust gases of the heat generator unit 12b be dissipated. Via an air supply line 52b becomes the heat generator unit 12b Supplied ambient air. The supplied ambient air is both process air for the fuel cell stack 42b as well as purge air used. The purge air preferably flows around all components of the heat generator unit that conduct a combustible gas 12b in order, in particular, to dilute flammable gas escaping due to any leaks and thus to prevent the formation of an explosive mixture. The portion of the supplied ambient air used as purge air is also via the exhaust pipe 14b dissipated.

The heating system 10b has two fans 16b . 66b on. While a first of the fans 16a serves to transport the scavenging air, serves a second of the blower 66b for transporting the process air and the exhaust gases of the heat generator unit 12b ,

To monitor the effectiveness of the purge air supply includes the heating system 10b a sensor unit 20b , which preferably continuously a flow characteristic of a gas flow 18b in the exhaust pipe 14b detected. For this purpose, the sensor unit 20b as a pressure sensor 26b trained sensor element 24b on. The pressure sensor 26b is intended to be a through the gas flow 18b caused pressure difference 28b between two measuring points 58b . 60b , which along the course of the at least one exhaust pipe 14b spaced and oppositely oriented to each other are arranged to determine. Alternatively, it is conceivable to arrange measuring points in an air supply line of ambient air in order to monitor the effectiveness of a purge air supply. Based on the pressure difference 28b may be a qualitative and / or quantitative assessment of gas flow 18b respectively. Preferably, the sensor element 24b such that, when the pressure difference is exceeded, a defined limit value is exceeded 28b a first output value and below the set limit value of the pressure difference 28b outputs a second output value. In particular, when falling below the limit, it must be assumed that there is no sufficiently strong gas flow 18b is present, whereupon the heating system 10b could be switched off safely.

To safely switch off the heating system 10b In case of failure, to be able to guarantee at any time, it is necessary, the function of the sensor unit 20b at regular intervals, for example every 24 hours. For this purpose, the heating system includes 10b a test unit 22b , The test unit 22b is intended during a functional test of the sensor unit 20b an input of the sensor unit 20b changed so that it results in a detectable change in the output value of the sensor unit 20b , in particular a switching from the first output value to the second output value or from the second output value to the first output value, results. In order to bring about a change in the input variable, a reversal of a conveying direction of the first blower takes place during a functional check 16b through the test unit 22b , Alternatively, it would be conceivable initially to reduce a delivery rate in the original delivery direction and then to increase it again in the reverse direction.

By reversing the conveying direction of the first blower 16b There is a change in the pressure levels at the two measuring points 58b . 60b , whereby a change in the output value of the sensor unit 20b is caused. If a change in the output value does not occur, this is due to a malfunction of the sensor unit 20b go out and the heating system 10b must be switched off. Also in this type of function control, the already resulting to the embodiment of 1 to 3 described advantages.

Claims (10)

Heating system with at least one heat generator unit ( 12a ; 12b ), with at least one exhaust pipe ( 14a ; 14b ), with at least one blower ( 16a ; 16b ) for generating a gas flow ( 18a ; 18b ) within the at least one exhaust pipe ( 14a ; 14b ) and with a sensor unit ( 20a ; 20b ), which in a measuring operating state to a detection of at least one flow characteristic of the gas flow ( 18a ; 18b ), characterized by a test unit ( 22a ; 22b ), which is intended, in a test operating state for a functional check of the sensor unit ( 20a ; 20b ) at least one input of the sensor unit ( 20a ; 20b ) in at least one test step, which differs from deactivating the at least one blower ( 16a ; 16b ) to change. Heating system according to claim 1, characterized in that the sensor unit ( 20a ; 20b ) a sensor element ( 24a ; 24b ), which in the measuring operating state is intended to output a first output value in the event of the first limit value being exceeded by the at least one flow characteristic value and a second output value in the case of a second limit value being undershot by the at least one flow characteristic value. Heating system according to claim 1 or 2, characterized in that the sensor unit ( 20a ; 20b ) at least one pressure sensor ( 26a ; 26b ), which is intended to a pressure difference ( 28a ; 28b ) within the at least one exhaust pipe ( 14a ; 14b ) capture. Heating system according to claim 3, characterized in that the at least one test unit ( 22a ) a bridging unit ( 30a ), which is provided to at least two inputs ( 32a . 34a ) of the at least one pressure sensor ( 26a ) during the test mode. Heating system according to claim 4, characterized in that the bridging unit ( 30a ) at least one valve ( 36a ) having. Heating system according to claim 5, characterized in that the test unit ( 22a ) is provided in Prüfbetriebszustand, the at least one Valve ( 36a ) and the at least one blower ( 16a ) together. Heating system according to claim 6, characterized in that the test unit ( 22a ) is provided in Prüfbetriebszustand, the at least one valve ( 36a ) and the at least one fan ( 16a ). Heating system according to one of the preceding claims, characterized in that the test unit ( 22b ) is provided in Prüfbetriebszustand to a conveying direction of the at least one blower ( 16b ) to reverse. Heating system according to one of the preceding claims, characterized in that the at least one heat generator unit ( 12a ; 12b ) as a fuel cell unit ( 38a ; 38b ) is formed and the at least one exhaust pipe ( 14a ; 14b ) is provided to dissipate at least a portion of a purge air. Method for operating a heating system ( 10a ; 10b ), in particular according to one of the preceding claims, with at least one heat generator unit ( 12a ; 12b ), with at least one exhaust pipe ( 14a ; 14b ), with at least one blower ( 16a ; 16b ) for generating a gas flow ( 18a ; 18b ) within the at least one exhaust pipe ( 14a ; 14b ) and with a sensor unit ( 20a ; 20b ), which in a measuring operating state to a detection of at least one flow characteristic of the gas flow ( 18a ; 18b ) is provided, characterized in that in a test operating state to a functional control of the sensor unit ( 20a ; 20b ) at least one input measurement of the sensor unit ( 20a ; 20b ) in at least one test step, which differs from deactivating the at least one blower ( 16a ; 16b ), is changed.

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