Compressor system having integrated ambient sensor

Abstract

The invention relates to a compressor system, in particular a screw compressor, for compressing gases, preferably air, the compressor system comprising: a compressor block (11) in which a compressor chamber (12) is formed in which the gas is compressed by means of mechanical compression means (13), wherein the compressor chamber (12) has an inflow-side inlet opening (14) and an outflow-side outlet opening (15); and a control device (16) for controlling a drive (17) of the compression means (13), wherein the control device (16) is operatively connected to a temperature sensor (19) and / or a humidity sensor (20) in order to determine conditions of the gas entering through the inlet opening (14), characterised in that the temperature sensor (19) and / or the humidity sensor (20) are / is located on or in the control device (16) inside the compressor system for measuring a temperature Tc prevailing therein and / or a humidity Fc prevailing therein, and the control device (16) comprises a processing device (23) in order to draw conclusions about the conditions of the gas entering through the inlet opening (14) from the measured values Tc and / or Fc.

Description

[0001] COMPRESSOR SYSTEM WITH INTEGRATED AMBIENT SENSOR

[0002] Description

[0003] The invention relates to a compressor system, in particular a screw compressor, for compressing gases, preferably air, comprising a compressor block in which a compressor chamber is formed, in which the gas is compressed via mechanical compression means, wherein the compressor chamber has an upstream inlet opening and a downstream outlet opening, as well as a method for controlling a compressor system, in particular for adjusting the temperature of the compressed gas at an outlet opening of a compressor block, taking into account state conditions of the gas flowing in at the inlet opening according to the preamble of patent claim 1 or the preamble of patent claim 16.

[0004] Especially with fluid-cooled compressors, it is desirable to set the temperature of the compressed gas at the outlet of the compressor chamber to a desired target discharge temperature TS,VET, whereby the temperature should always be high enough to prevent condensation within the compressed gas with sufficient reliability. At the same time, the target discharge temperature T S However, the target compression temperature Ts,VET should not be set too high, which can be achieved, for example, by using a fluid cooling circuit that cools the compressor chamber. Especially for compressors cooled by a fluid cooling circuit, the target compression end temperature Ts,VET should not be set too high to protect the cooling fluid.

[0005] A compressor system of this type is already known from US 8,226,378 B2. There, the formation of condensate in the compressed gas of a screw compressor is prevented by regulating the cooling capacity of an oil cooling circuit via a bypass valve. When setting the temperature of the compressed gas at the outlet opening of the compressor chamber as proposed there, the condition of the supply air flowing into the compressor chamber is also determined via a temperature sensor and a humidity sensor. Specifically, in a preferred embodiment, it is proposed to use the temperature sensor to detect a gas temperature T representative of the condition of the gas at the upstream inlet opening. e and the humidity sensor for detecting a humidity level representative of the gas condition at the upstream inlet opening on the outside of the compressor system.

[0006] Although in principle the state conditions for the gas flowing into the compressor chamber can be determined, the teaching proposed therein nevertheless results in some disadvantages.

[0007] As far as the temperature sensor is concerned, incorrect readings can occur, for example, if the sensor is exposed to waste heat from the engine. This effect is particularly pronounced when the intake flow rate is low and a relatively high proportion of gas heated by the waste heat is drawn in.

[0008] As for the humidity sensor, it is exposed to correspondingly high particle loads and contamination outside the compressor system, which can distort measurement results. The effect of contamination is noticeable outside the compressor system and increases significantly with increasing operating time.

[0009] It is also conceivable to place a temperature or humidity sensor downstream of the intake air filter and upstream of an inlet valve in a compressor system. In this area, a filtered gas flow typically exists; however, oil mist can form when the compressor system is vented. This exposes the temperature or humidity sensor to a certain risk of contamination. Furthermore, the area between the air filter and the inlet valve is subjected to the entire intake volume flow of the compressor system, so that due to the relatively high volume flow, a relatively high particle load for the temperature or humidity sensor exists over its entire service life despite the presence of the inlet filter.

[0010] The object of the present invention, based on the discussed prior art, is to propose a solution in which the desired temperature TVET of the compressed gas at the outlet opening of the compressor chamber can be determined even more reliably, taking into account the conditions of the gas flowing in at the inlet opening. In this respect, a structurally improved solution is also to be created.

[0011] This object is achieved in terms of device technology by a compressor system according to the features of claim 1 and in terms of process technology by the features of claim 16. Advantageous further developments are specified in the subclaims.

[0012] A key idea of ​​the present invention is to arrange the temperature sensor and / or the humidity sensor on or in the control device within the compressor system in order to detect a temperature T prevailing there. c or a humidity F prevailing there c , wherein the control device comprises a processing device for determining from the measured values ​​T c and / or F c to draw conclusions about the state conditions of the gas entering the inlet opening.

[0013] The conditions of the gas entering the inlet opening can be understood as individual physical parameters or a combination of physical parameters, such as in particular a temperature Tein, a humidity Fein, a dew point Tau ein, a water vapor content WDGein or a pressure Pein. With regard to the steps mentioned in connection with the subject matter of the invention, such as "determining," "inferring," and "controlling the actuating means," it is clarified that these steps are carried out automatically and independently by the control device.

[0014] The proposed solution offers several advantages. Firstly, the humidity sensor and temperature sensor are much better protected against contamination and damage in this design than if they were mounted on or in the intake area of ​​the compressor system. Furthermore, manufacturing is simplified because long supply lines for power and / or data transmission are not necessary. Finally, operation is also improved because a more direct connection to the control device also brings further practical advantages in terms of operation: When connected to the control device, the processing of the process data value in the form of calibration, characteristic curve correction, measuring range adjustment, etc. can be carried out directly within the control device or the MEMS sensor, especially if the humidity sensor and / or the temperature sensor is integrated into a MEMS sensor.directly within the MEMS sensor and a digital value is provided at the data interface.

[0015] Conventional sensors, on the other hand, usually have analog interfaces (0...10 V or (0) 4...20 mA), which must be read via an analog input circuit and scaled, normalized, and, if necessary, zero-corrected, and calibrated accordingly. A downstream analog-to-digital converter is required to process the process value. These processing steps are error-prone and subject to a certain degree of drift due to the temporal changes in the components used.

[0016] Discrete sensors, which already have appropriate internal signal conditioning and provide the data digitally, e.g., via a fieldbus interface, are preferable. However, such sensors are expensive.

[0017] A humidity and / or temperature sensor integrated into the control system can be put into operation with the control system. This means that these sensors can be decoupled from the compressor in time and space, commissioned, and functionally tested, unlike the aforementioned discrete sensors, which only provide data after installation and commissioning.

[0018] A possible prejudice that the condition of the gas entering the inlet opening must be determined as close as possible to the inlet opening in the compressor chamber has proven to be incorrect. On the one hand, the conditions in the area of ​​the inlet opening can be deduced using correction factors or a corresponding allocation table. On the other hand, the values ​​regarding absolute humidity, i.e. the dew point or the water vapor content, do not differ noticeably between the environment at the upstream inlet opening of the compressor chamber on the one hand and the conditions at or in the control device. In this respect, it has been shown that the values ​​representative of the condition of the gas in the area of ​​the upstream inlet opening can also be determined using a temperature sensor or a humidity sensor arranged on or in the control device within the compressor system.Of course, a certain gas exchange is assumed between the gas in the vicinity of the upstream inlet opening on the one hand and the gas at or in the control device on the other.

[0019] In a preferred development of the present invention, the compressor system also comprises an actuating means, in particular a cooling fluid bypass valve, and the control device controls the actuating means based on the values ​​obtained from T c and / or F c determined state conditions of the incoming gas at the inlet opening.

[0020] Although the control of one or more actuating means is dependent on the determined state conditions, the state conditions detected according to the invention can also be used for various other applications.

[0021] In a possible embodiment, the control device is further based on the one from T cand / or F c determined state conditions of the incoming gas at the inlet opening, designed and arranged to control the compressor system in such a way that the temperature of the compressed gas at the outlet opening of the compressor chamber follows a desired final compression temperature Ts, VET.

[0022] In a further embodiment, the control device is furthermore operatively connected to a pressure sensor in order to also determine a pressure value P c and taking into account the pressure value P c to draw even more precise conclusions about the state conditions of the gas entering the inlet opening.

[0023] In a further embodiment, the pressure sensor is arranged on or in the control device within the compressor system.

[0024] In a preferred embodiment, the control device is accommodated in a control housing within the compressor system, wherein the temperature sensor and / or the humidity sensor are also accommodated within the control housing.

[0025] In a preferred embodiment, the control housing is at least largely closed, in particular closed except for a few openings, in particular except for two openings. The control housing can be a housing that directly encloses the electronic control device. In this case, the volume enclosed by the control housing essentially corresponds to the volume occupied by the electronic control device or is not significantly larger. However, the control housing can also be implemented as a control cabinet that accommodates not only the control device itself but also other electronic components, such as a power supply. By being accommodated within the control housing, the temperature sensor and / or the humidity sensor are even better protected from adverse external influences, such as damage or contamination.

[0026] A particularly preferred embodiment results from the fact that the temperature sensor and / or the humidity sensor can be integrated on a circuit board on which electronic components of the control device, in particular a main processor of the control device, are also arranged. The main processor can form the processing unit of the control device.

[0027] By integrating the control unit onto a circuit board, a solution has been created that is particularly cost-effective both in terms of manufacturing and operation. Temperature sensors and humidity sensors are now available as miniaturized components that can be easily integrated onto a circuit board. In this respect, the functionality of a temperature sensor can be used to record the conditions of the gas entering the inlet opening, for example, a dew point Tauein of the gas in the vicinity of the upstream inlet opening or to estimate a temperature Tein or Tein representative of the environment at the upstream inlet opening of the compressor chamber.a humidity level representative of the environment at the upstream inlet opening of the compressor chamber can be easily achieved using electronic components that can be integrated onto the circuit board with other components of the control device, such as the main processor, in a preferably automated process. This reduces manufacturing costs, in particular connection and cabling costs, when implementing the compressor system. At the same time, a close connection to the main processor of the control device is enabled, so that signal propagation times and transmission errors can be significantly reduced. In a very specific preferred embodiment, the temperature and / or humidity sensor can be designed as a MEMS sensor. Although the humidity sensor and temperature sensor could also be structurally implemented separately, it is nevertheless conceivable to incorporate the humidity sensor and temperature sensor into a common MEMS sensor.MEMS sensors (micro-electro-mechanical systems) are now commonplace in many areas of technology, especially in air conditioning, and are offered by various manufacturers. Their functionality includes detecting the condition of the gas entering the inlet, such as the dew point. e in or a water vapor content WDGin of the gas in the vicinity of the inlet opening or a temperature representative of the environment at the inlet opening of the compressor room or to record a humidity representative of the environment at the inlet opening of the compressor room can be realized in a cost-effective manner.

[0028] At the same time, a closer spatial and functional connection to the control device, in particular a main processor of the control device, can be created. In a preferred embodiment, fluidic coupling means are provided on or in the control device to couple or better couple the temperature sensor and / or the humidity sensor to the environment or to the air in the environment upstream of the inlet opening.

[0029] In this respect, such fluidic coupling means can comprise corresponding openings in the control housing of the control device. Through such openings, ambient air, in particular ambient air from near the inlet opening of the compressor chamber, can be introduced into the control housing and directed to the temperature sensor and / or humidity sensor, and subsequently also discharged from the control housing.

[0030] The fluidic coupling means can also comprise a cooling air flow guide and / or a fan to guide or drive the supply air flow. In one possible embodiment, the cabinet ventilation already provided in a control cabinet is incorporated, i.e. the desired supply air flow for supplying air from the environment at the inlet opening of the compressor chamber or air with the same or similar condition can be achieved by the cabinet ventilation already provided. In a further preferred embodiment, the fluidic coupling means can also comprise a cooling air flow guide formed in the control housing for guiding a cooling air flow, wherein the fan is provided to drive the cooling air flow.By means of the cooling air flow guide within the control housing, it is possible to determine to which components of the control device and in which sequence the cooling air flow should be guided, whereby in a first possible embodiment the cooling air flow or the supply air flow for the temperature sensor and / or the humidity sensor should not yet be exposed to waste heat from the components to be cooled, i.e. the supply air flow is first guided to the temperature sensor and / or the humidity sensor and only then does it absorb waste heat from the control device and is discharged from the control housing as a cooling air flow.

[0031] In an alternative possible embodiment, the cooling air flow or the supply air flow is first guided over the components to be cooled and only then over the temperature sensor and / or the humidity sensor. In this case, the cooling air flow or the supply air flow first absorbs the waste heat from the control device before reaching the temperature sensor or humidity sensor. However, this is equally suitable for determining the absolute air humidity or the dew point, since the absolute air humidity is not affected by this heating. At the same time, there is the advantage that the lower relative air humidity counteracts condensation on the humidity sensor, thus improving the reliability of the humidity measurement.In general, it should be noted that integrated humidity sensors are also available which have an internal heater to prevent condensation, which is switched on when there is a risk of condensation.

[0032] In a further preferred embodiment, a filter is provided and arranged in the cooling air flow duct such that the supply air flow is first guided over the supply air filter before reaching the temperature sensor and / or the humidity sensor. This allows additional particles to be removed from the supply air, thus further counteracting contamination of the temperature sensor and / or the humidity sensor.

[0033] In a preferred embodiment, the spacing between the temperature sensor and the main processor of the control device is less than 30 cm, preferably less than 20 cm. Alternatively or additionally, in a preferred embodiment, the spacing between the humidity sensor and the main processor of the control device is less than 30 cm, preferably less than 20 cm.

[0034] In a preferred embodiment of the present invention, the temperature sensor is connected directly to the main processor of the control device or the humidity sensor is connected directly to the main processor of the control device, in particular without the interposition of further components, interfaces, etc. This procedure allows a direct connection and avoids longer signal propagation times, incorrect transmissions or requirements for the structural or programmatic design of interfaces.

[0035] In a preferred embodiment, the compressor system has a fluid cooling circuit, the cooling capacity of which can be adjusted via adjusting means, such as one or more valves, wherein the control device adjusts the cooling capacity of the fluid cooling circuit taking into account the state conditions of the gas flowing in at the inlet opening, as determined via the temperature sensor or the humidity sensor, in particular taking into account the temperature Tin or humidity Fine of the gas flowing in at the inlet opening thus determined. In this respect, depending on the determined values ​​Tin or Fine or the dew point Tau e in or water vapor content WDG- the cooling capacity can be increased or reduced.

[0036] This ensures, particularly taking into account the absolute humidity or dew point in the vicinity of the inlet opening, that condensation in the compressed gas is avoided with sufficient certainty and, at the same time, the temperature TVET can be kept as low as possible.

[0037] Specifically, the temperature Tein and the humidity Fine can be used to determine the water vapor content / dew point of the intake gas, and thus a minimum target discharge temperature TS,VET required to prevent condensation can be determined as an input variable / setpoint for a VET controller. This controller controls the actuator(s) in the fluid circuit and / or the amount of cooling medium and / or the speed of a fan motor to a cooling fluid cooler. The actual discharge temperature TI,VET is measured at the outlet of the compressor block.

[0038] In a specifically preferred embodiment, the control means comprise a cooling fluid bypass valve, which is operatively connected to the control device and which can be used to gradually adjust the amount of cooling fluid that is passed through a heat exchanger integrated in the fluid cooling circuit or bypassed by the heat exchanger integrated in the fluid cooling circuit. This configuration for regulating the cooling capacity of the cooling fluid circuit is common practice in compressor systems. Reference is again made to the aforementioned US Pat. No. 8,226,378 B2 purely by way of example.

[0039] The method according to the invention for controlling a compressor system, in particular for setting the actual final compression temperature Ti, VET of the compressed gas at an outlet opening of a compressor block, taking into account the state conditions of the gas flowing in at the inlet opening, wherein a temperature T cand / or a humidity F c is determined on or in a control device to detect a temperature T prevailing on or in the control device c or a humidity F prevailing on or in the control device c and that from the measured values ​​T c and / or F c the state conditions of the gas entering at the inlet opening are inferred.

[0040] In an advantageous embodiment of the present method, the temperature T measured at the temperature sensor on or in the control device is c and from the humidity F measured at the humidity sensor on or in the control device c Dew point representative of the air in the area of ​​the control device c or another value representative of the water vapor content of the air in the area of ​​the control device WDG C and the dew point dew cor the value WDG representative of the water vapor content C when determining the target compression end temperature T S ,VET of the compressed gas at the outlet of the compressor block is taken into account.

[0041] In a further preferred development of the method, the temperature T c or the humidity F c in a supply air stream guided through the control device. In a preferred development of the method, the supply air stream passes through a filter to remove particles from the supply air before it reaches the temperature sensor or the humidity sensor.

[0042] In a possible preferred embodiment, the temperature T measured at the temperature sensor is c to a temperature of the gas Tein at the inlet opening of the compressor chamber.

[0043] In a further possible preferred embodiment, the temperature T measured at the temperature sensor is c and the humidity F measured at the humidity sensor c to a dew point dew e in or a water vapor content WDGin of the gas at the inlet opening of the compressor chamber. In this respect, inference also includes deriving, determining, or calculating by the control device.

[0044] In a further possible preferred embodiment, the compressor system is cooled via an adjustable fluid cooling circuit in order to keep an actual final compression temperature Ti, VET as close as possible to a desired final compression temperature TS, VET ZU, wherein the cooling capacity of the fluid cooling circuit is adjusted taking into account the state conditions of the gas flowing in at the inlet opening of the compressor system, in particular taking into account the temperature Tein determined in this way or the humidity Fein determined in this way.

[0045] In a further possible preferred embodiment, the cooling capacity of the cooling fluid circuit is adjusted via a bypass control.

[0046] In a further preferred embodiment of the method according to the invention, it can be provided that a pressure on or in the environment of the control device is determined via a pressure sensor, wherein the pressure determination is preferably carried out by a pressure sensor on or in the control device.

[0047] For the sake of clarity, it is pointed out that the humidity F measured by the humidity sensor is c It is a relative humidity and not an absolute humidity. The invention will be explained in more detail below with regard to further features and advantages based on the description of exemplary embodiments and with reference to the accompanying drawings.

[0048] Here we show:

[0049] Figure 1 is a schematic representation of a compressor system provided with a fluid cooling circuit, which is equipped with a temperature sensor according to the invention and a humidity sensor according to the invention for determining the gas temperature Tein or the gas humidity Fein;

[0050] Figure 2 shows a control device of a compressor system provided with a corresponding temperature sensor or humidity sensor;

[0051] Figure 3 shows a first alternative embodiment for integrating a humidity sensor and a temperature sensor and a humidity sensor on a circuit board of a control device of a compressor system;

[0052] Figure 4 shows an alternative embodiment for realizing an integration of a temperature sensor and a humidity sensor on a circuit board of a control device of a compressor system.

[0053] Figure 1 shows a schematic representation of a compressor system 37 provided with a fluid cooling circuit 27, which is equipped with a temperature sensor 19 according to the invention and a humidity sensor 20 according to the invention for determining a gas temperature Tein and a gas humidity Fein at an inlet opening 14 of a compressor block 11. The compressor block 11 comprises the aforementioned inlet opening 14, a compressor chamber 12 enclosed by the compressor block 11, and an outlet opening 15. Mechanical compression means 13, specifically two screws here, are mounted in the compressor chamber 12. These screws compress gas flowing into the inlet opening 14 according to the principle of a screw compressor and discharge it at an outlet opening. Adjacent to the outlet opening 15 is an oil separator 31, into which the compressed gas enters and into which a cooling and lubricating fluid, specifically oil here, is separated.The compressed gas, freed from the cooling fluid (here oil), is fed to a consumer or consumer network via an outlet line 32. The oil separator 31 is also part of the aforementioned fluid cooling circuit 27, which returns the cooling fluid (here oil) separated from the compressed gas to the compressor chamber 12 via an injection point 33.

[0054] In order to be able to adjust the temperature of the cooling fluid returned to the injection point 33, an adjusting means, which is specifically designed here as a cooling fluid bypass valve 18, is provided in order to return the cooling fluid either directly from the oil separator to the injection point or to pass it wholly or partially via a heat exchanger 28 before it is returned to the injection point 33.

[0055] The compressor system further comprises a control device 16, which is housed in a control housing 21 on or within the compressor system. The control housing 21 has a first inflow opening 25 and a second outflow opening 34 for directing an air flow through the control housing 21. To drive the aforementioned air flow, a fan 26 is provided, preferably on the downstream side of the control device 16.

[0056] The control device 16 comprises one or more circuit boards 22, on which, for example, a main processor 23 of the control device 16 is arranged. Furthermore, in a preferred embodiment of the present invention, the aforementioned temperature sensor 19 or the aforementioned humidity sensor 20 can also be arranged on a circuit board 22 of the control device 16, preferably on the circuit board 22 on which a main processor 23 of the control device is also arranged, and in this respect, this circuit board can also be referred to as the main board.

[0057] In a further preferred embodiment, the temperature sensor 19 and / or the humidity sensor 20 are connected directly to the main processor 23 of the control device 16, i.e., no further interfaces or other components are interposed. The circuit board 22 with the main processor 23 of the control device 16 is preferably arranged within the control housing 21 in such a way that an air flow entering from the upstream opening 25 first passes over the temperature sensor 19 and the humidity sensor 20 before being heated by the main processor 23 and / or the fan 26. In a particularly preferred embodiment, the temperature sensor 19 and / or the humidity sensor 20 are designed as MEMS sensors (micro-electro-mechanical systems).

[0058] In the embodiment specifically described here, the control device 16 is also operatively connected to a pressure sensor 36, which is used to detect a pressure value P cis formed. Preferably, the pressure sensor 36 is also arranged on a circuit board 22 of the control device 16, preferably likewise on the circuit board 22 on which a main processor 23 of the control device is also arranged. Particularly preferably, the pressure sensor 36 is also designed as a MEMS sensor. The gas or air pressure can be determined via the pressure sensor 36. The air pressure influences the compression process and may also influence other parameters of the compressor system. The air pressure depends significantly on the installation altitude of the compressor system above sea level, but is also influenced, for example, by weather conditions. The latter, however, have only a comparatively minor effect.

[0059] Without air pressure sensors, calculations typically assume an atmospheric pressure of 1.0 bar, which would correspond to a compressor system installed at sea level. This simplifies the calculation in that only the discharge pressure, and not the intake air pressure, is considered for the pressure ratio n. This simplification requires a suitable safety margin to be considered when calculating the target discharge temperature Ts, VET ZU.

[0060] If the air pressure pi is known, it can be taken into account in the calculation, and the pressure ratio n = pi / p2 applies, where pi is the intake air pressure in bar (abs), P2 is the final compression pressure in bar (abs). With pi = 1.0 bar (abs), n = p2 applies. If pi is less than 1.0 bar (abs), for example, due to a higher installation altitude of the compressor system above sea level, the pressure ratio n increases and thus has a corresponding influence on the target final compression temperature T to be calculated. S ,VET .

[0061] Figure 2 shows the control housing 21 from Figure 1 again in an isolated form, with the control device 16 housed therein. Reference is made to the description in connection with Figure 1. By structurally modifying the control housing 21 or corresponding devices, a cooling air flow guide 30 can be defined, which guides the cooling air flow driven by the fan 26 in a desired path. To further reduce contamination of the temperature sensor 19 or the humidity sensor 20, an air filter 35 is advantageously arranged in the cooling air flow guide 30, preferably in the region of the inflow-side opening 25, to retain particles from the incoming air.

[0062] With the arrangement proposed here, the temperature sensor 19 and the humidity sensor 20 can determine a gas temperature representative of the gas temperature or the gas humidity at the inlet opening 14 of the compressor chamber 12. If necessary, the specifically measured temperature or the specifically measured humidity can be further corrected using correction factors or correlation tables in order to more accurately determine the value Tin or fine, i.e. the gas temperature or the gas humidity at the inlet opening 14 of the compressor chamber 12. In addition to calculating or estimating a temperature Tin or a humidity fine, the measured values ​​of the temperature T c on or in the control device 16 and the humidity F c on or in the control device 16 to a dew point dew c or the water vapor content WDGc of the gas in the area of ​​the control device 16. From the calculated value Tau cor WDG C can be directly deduced from the dew point Tauein or the water vapor content WDGein at the inlet opening 14 of the compressor chamber 12, whereby the value Tau c or WDGc 1:1 can be assumed, or correction factors could also be incorporated. In general, however, it is assumed that the absolute water vapor content of the gas at both locations, namely at or in the control device 16 on the one hand, and in the region of the inlet opening 14 of the compressor chamber 12 on the other hand, is the same or at least substantially the same. Figure 3 illustrates an embodiment in which the temperature sensor 19 and the humidity sensor 20 are designed as MEMS sensors and are each directly connected to the main processor 23 of the control device 16.

[0063] Figure 4 illustrates an embodiment in which the temperature sensor 19 and the humidity sensor 20 are integrated in a common MEMS sensor and this is directly connected to the main processor 23 of the control device 16.

[0064] In a preferred aspect of the present invention, the dew point Tau is determined c from the measurement of temperature T c and the corresponding relative humidity F c on or in the control device 16. These value pairs allow a calculation of the water vapor content WDG C or the dew point Tau c. It is assumed that, without additional effects, the water vapor content of the interconnected gas volumes, namely the gas volumes in the area of ​​the control device 16 on the one hand and the inlet opening 14 of the compressor chamber 12 on the other hand, is the same or essentially the same. Consequently, in a compressor that draws gas, in particular air, from its surroundings, the dew point can be determined in each gas volume that is also directly connected to the area of ​​the inlet opening of the compressor. The dew point is determined exclusively by the water vapor content of the gas drawn in by the compressor. The water vapor content is, within certain limits, independent of fluctuations in the gas temperature, but can only be determined indirectly by measuring the gas temperature and relative humidity. According to an advantageous aspect of the present invention, the gas temperature T c and the relative humidity F con or in the control device. If a heat source were to cause an increase in temperature, the relative humidity would decrease accordingly, since the water vapor content remains unchanged by the temperature change. Thus, the temperature sensor 19 and the humidity sensor 20 can also be placed in a warmer area of ​​the machine, namely on or in the control device.

[0065] An additional advantage arises from the fact that the placement of the humidity sensor 20 on or in the control device 16 counteracts condensation on this humidity sensor 20. If the temperature sensor 19 or the humidity sensor 20 is placed in the control cabinet, a relatively low particle load can be expected, since cooling air for the control cabinet is always filtered. Condensation on the temperature sensor 19 or humidity sensor 20 is to be feared when the relative humidity approaches 100%. This would be the case if the temperature and dew point approach each other. If the dew point remains the same, an increase in temperature leads to a reduction in the relative humidity and consequently to a reduced risk of sensor condensation. In the prior art, in which humidity sensors are mounted on an outside or inside the control device 16, the risk of condensation on the temperature sensor 19 or the humidity sensor 20 is reduced.For example, if the sensors are located at or near the compressor outlet, there is an additional risk that a layer of condensation will form on the humidity sensor at colder gas temperatures, and this condensation will distort or even prevent the relative humidity measurement. Therefore, the solution proposed here can also overcome this problem.

[0066] By determining the pressure P c of the ambient air, this influence on the target discharge temperature Ts, VET can be taken into account. This makes the recording of the conditions of the gas entering the inlet of the compressor system more accurate, on the one hand because weather fluctuations are also taken into account, but above all because if the installation altitude above sea level is incorrectly entered during initialization of the compressor system, such incorrect parameterization can be compensated for by the actual recording of the pressure P cthe ambient air can be corrected.

[0067] List of reference symbols Compressor block Compressor chamber Compression means Inlet opening Outlet opening Control device Drive Actuating means, cooling fluid bypass valve Temperature sensor Humidity sensor Control housing Circuit board Main processor Fluidic coupling means Inflow opening Fan Fluid cooling circuit Heat exchanger Housing ventilation Cooling air flow guide Oil separator Outlet line Injection point Downflow opening Air filter Pressure sensor Compressor system

Claims

Claims 1. Compressor system, in particular a screw compressor, for compressing gases, preferably air, comprising a compressor block (11) in which a compressor chamber (12) is formed, in which the gas is compressed via mechanical compression means (13), wherein the compressor chamber (12) has an inlet opening (14) on the upstream side and an outlet opening (15) on the downstream side, and a control device (16) for controlling a drive (17) of the compression means (13), wherein the control device (16) is operatively connected to a temperature sensor (19) and / or a humidity sensor (20) in order to determine the state conditions of the gas entering at the inlet opening (14), characterized in that the temperature sensor (19) and / or the humidity sensor (20) are arranged on or in the control device (16) within the compressor system for detecting a temperature T prevailing there. cor a humidity F prevailing there c and the control device (16) comprises a processing device (23) for determining from the measured values ​​T c and / or F c to draw conclusions about the state conditions of the gas entering at the inlet opening (14).

2. Compressor system according to claim 1, characterized in that the compressor system comprises an actuating means, in particular a cooling fluid bypass valve, and that the control device uses corresponding control commands to actuate the actuating means based on the values ​​obtained from T c and / or F c determined state conditions of the incoming gas at the inlet opening (14).

3. Compressor system according to claim 1, characterized in that the control device further based on the from T c and / or F cdetermined state conditions of the incoming gas at the inlet opening (14) is designed and arranged to control the compressor system in such a way that the temperature of the compressed gas at the outlet opening (15) of the compressor chamber (12) of a desired compression end temperature T S ,VET follows.

4. Compressor system according to one of claims 1 to 3, characterized in that the control device (16) is further operatively connected to a pressure sensor (36) in order to also determine a pressure value P c and taking into account the pressure value P c to draw conclusions about the state conditions of the gas entering at the inlet opening (14).

5. Compressor system according to claim 4, characterized in that the pressure sensor (36) is also arranged on or in the control device (16) within the compressor system.

6. Compressor system according to claim 1, characterized in that the control device (16) is accommodated in a control housing (21), wherein the temperature sensor (19) and / or the humidity sensor (20) is also accommodated within the control housing (21).

7. Compressor system according to one of claims 1 to 6, characterized in that the control device (16) comprises one or more circuit boards (22) with electronic components, in particular a main processor (23) of the control device (16), and that the temperature sensor (19) and / or the humidity sensor (20) is / are also arranged on the one or more circuit boards.

8. Compressor system according to one of claims 1 to 7, characterized in that the temperature sensor (19) is designed as a MEMS sensor.

9. Compressor system according to one of claims 1 to 8, characterized in that the humidity sensor (20) is designed as a MEMS sensor.

10. Compressor system according to one of the preceding claims, characterized in that the temperature sensor (19) and the humidity sensor (20) are integrated in a MEMS sensor.

11. Compressor system according to one of claims 1 to 10, characterized in that fluidic coupling means (24) are provided in order to couple the temperature sensor (19) and / or the humidity sensor (20) to the environment, in particular to the air in the environment, upstream of the inlet opening (14).

12. Compressor system according to claim 11, characterized in that the fluidic coupling means (24) comprise corresponding openings (25) in the control housing (21) of the control device (16).

13. Compressor system according to claim 11 or 12, characterized in that the fluidic coupling means (24) comprise a cooling air flow guide (30) and / or a fan (26) in order to guide or drive a supply air flow.

14. Compressor system according to claim 13, characterized in that the fan (26) is provided as a component of a housing ventilation (29) on or in the control housing (21).

15. Compressor system according to claim 13 or 14, characterized in that a cooling air flow guide (30) for guiding a cooling air flow is formed in the control housing (21), wherein the fan (26) also drives the cooling air flow.

16. Compressor system according to one of claims 13 to 15, characterized in that an air filter (35) is provided and arranged in the cooling air flow guide (30) in such a way that the supply air flow first passes through the supply air filter (35) before it reaches the temperature sensor (19) and / or the humidity sensor (20).

17. Compressor system according to one of claims 8 to 16, characterized in that a spacing between the temperature sensor (19) and the main processor (23) of the control device (16) is less than 30 cm, preferably less than 20 cm and / or the spacing between the humidity sensor (20) and the main processor (23) of the control device (16) is less than 30 cm, preferably less than 20 cm.

18. Compressor system according to one of claims 1 to 17, characterized in that the temperature sensor (19) is connected directly to the main processor (23) of the control device (16) or the humidity sensor (20) is connected directly to the main processor (23) of the control device (16), in particular without the interposition of further components, interfaces, etc.

19. Compressor system according to one of claims 1 to 18, characterized in that the compressor system has a fluid cooling circuit (27) whose cooling capacity can be adjusted via the adjusting means, such as one or more valves, and the control device (16) adjusts the cooling capacity of the fluid cooling circuit (27) taking into account the state conditions of the gas flowing in at the inlet opening (14) determined via the temperature sensor (19) or the humidity sensor (20), in particular taking into account the temperature Tin or humidity Fine of the gas flowing in at the inlet opening (14) determined in this way.

20. Compressor system according to claim 19, characterized in that the adjusting means comprise a cooling fluid bypass valve (18) by means of which the quantity of cooling fluid can be gradually adjusted via a fluid cooling circuit (27) integrated heat exchanger (28) or on the heat exchanger (28) is passed.

21. Method for controlling a compressor system, preferably according to one of claims 1 to 20, in particular for adjusting the temperature of the compressed gas at an outlet opening (15) of a compressor block (11) taking into account the state conditions of the gas flowing in at the inlet opening (14), characterized in that a temperature T c and / or a humidity F c is determined on or in a control device to detect a temperature T prevailing on or in the control device c or a humidity F prevailing on or in the control device c and that from the measured values ​​T c and / or F c the state conditions of the gas entering at the inlet opening (14) are deduced.

22. Method according to claim 21, characterized in that from the temperature T measured at the temperature sensor (19) on or in the control device (16) c and from the humidity F measured at the humidity sensor (20) on or in the control device (16) c Dew point representative of the air in the area of ​​the control device (16) c or another value representative of the water vapor content of the air in the area of ​​the control device is calculated and the dew point Tau c or the value WDG representative of the water vapor content C when determining the target compression end temperature T S ,VET of the compressed gas at the outlet opening (15) of the compressor block (11) is taken into account.

23. Method according to claim 21 or 22, characterized in that the temperature T c or the humidity F c in a supply air flow guided via the control device.

24. Method according to claim 23, characterized in that the supply air flow, before it hits the temperature sensor (19) or the humidity sensor (20), passes through a filter to remove particles.

25. Method according to one of claims 21 to 24, characterized in that from the temperature T measured at the temperature sensor (19) c a temperature of the gas Tein at the inlet opening (14) of the compressor chamber (12) is deduced.

26. Method according to one of claims 21 to 25, characterized in that from the temperature T measured at the temperature sensor (19) c and the humidity F measured at the humidity sensor (20) c a dew point Tein or a water vapor content WDGein of the gas at the inlet opening (14) of the compressor chamber (12) is inferred.

27. Method according to one of claims 21 to 26, characterized in that the compressor system is cooled via an adjustable fluid cooling circuit in order to keep an actual final compression temperature Actual final compression temperature Ti, VET as close as possible to a desired final compression temperature Ts, VET, wherein the cooling capacity of the fluid cooling circuit is adjusted taking into account the state conditions of the gas flowing in at the inlet opening of the compressor system, in particular taking into account the temperature Tein determined in this way or the humidity Fein determined in this way.

28. Method according to claim 27, characterized in that the cooling capacity of the cooling fluid circuit is adjusted via a bypass control.

29. Method according to one of claims 1 to 28, characterized in that a pressure prevailing in the environment of the control device (16) is determined via a pressure sensor (36) on or in the control device (16).

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