Method for preventing condensation in a compressor and compressor system

Abstract

The present invention relates to a method (100) for preventing condensation in a compressor, in particular a compressor of an air treatment / supply system of a vehicle, wherein the pressure dew point (Tdpres) of the compressed air is calculated (106) based on input parameters, wherein the input parameters comprise a system pressure and ambient conditions. Moreover, the present invention refers to a compressor system.

Description

[0001] DESCRIPTION

[0002] Method for preventing condensation in a compressor and compressor system

[0003] The present invention refers to a method for preventing condensation in a compressor, in particular a compressor of an air treatment / supply system of a vehicle.

[0004] Air compressors are integral components in vehicles such as trucks, buses, and construction equipment, providing compressed air to essential systems like brakes, suspensions, and pneumatic auxiliaries. These compressors function by compressing atmospheric air, which generates heat. However, as the compressor operates, the temperature of the compressed air can fluctuate due to various phases of its operation.

[0005] During the start-up phase, when the compressor is first activated, it operates at a lower temperature since it has not yet reached thermal equilibrium. As the compressor runs and begins to handle the load, the temperature of the compressor (e.g. on the compressor housing) rises. Once the compressor reaches steady-state operation, the temperature typically stabilizes. The internal temperature of the compressor can be influenced by factors such as the ambient temperature, the load on the compressor, and the efficiency of heat dissipation mechanisms (like cooling systems or radiators). During the steady-state operation phase, the temperature of the compressed air and internal components remains relatively stable.

[0006] During the shutdown phase, when the compressor is turned off, the temperature gradually decreases as the compressor cools down. This cooling process is influenced by the surrounding environment and the thermal properties of the compressor materials.

[0007] When the compressor's temperature falls below the critical threshold known as the pressure dew point (Tdpres), the water vapor in the compressed air condenses into liquid. Additionally, the air drawn into the compressor carries moisture that can condense on internal surfaces if the pressure dew point is higher than the compressor housing temperature. This condensation can cause corrosion of the compressor components, potentially compromising their longevity and performance. This issue is especially problematic during low duty cycles or when the compressor remains inactive for extended periods, as the accumulated moisture may not evaporate effectively. The presence of water inside the compressor causes several significant risks. It can cause internal corrosion of the compressor components, degrade the lubricating oil in oil-lubricated compressors, cause high oil-carry-over and ultimately result in compressor failure. Additionally, compressors that operate at low duty cycles may not generate sufficient heat to reach temperatures above the dew point, exacerbating the problem of water accumulation.

[0008] It is an object of the invention to develop an advanced control method for air compressors that addresses the problem of liquid water accumulation. Advantageously, the method helps in designing strategies to optimize compressor performance, manage condensation, and ensure reliable operation.

[0009] This object is achieved by a method for preventing condensation in a compressor according to independent claim 1 . Preferred embodiments are addressed by the dependent claims respectively.

[0010] According to the present invention, a method for preventing condensation in a compressor, in particular a compressor of an air supply system of a vehicle is provided. The method comprises the steps of:

[0011] - starting the compressor;

[0012] - obtaining an actual speed and a nominal speed of the compressor;

[0013] - calculating the pressure dew point (Tdpres) of the compressed air based on input parameters, wherein the input parameters comprise a system pressure and ambient conditions, including ambient temperature and relative humidity;

[0014] - calculating an anticondensation phase parameter (X) using the formula (given for acquisition frequency 1 Hz - other frequency possible with adaptation of the formula): wherein Ti is an adjusted temperature determined for instance by adding a predetermined constant parameter value (C) to the calculated dew point temperature (Tdpres), Tcomp (x) is the temperature of the compressor at time x (seconds after compressor start), Nactual represents the actual speed of the compressor, Nnominal represents the nominal speed of the compressor, Bacc represents an indirect quantification of the accumulated condensed water inside the compressor; and - activating a first signal to command the compressor operate until either the anticondensation parameter value X reaches 0 or a predefined maximum running time limit is reached, or another condition defined by the conceptor is reached, whichever occurs first.

[0015] The present invention is based on the idea to monitor condensation and evaporation phases of the moisture in the compressor. Once this balance is achieved between two phases, there is no longer any liquid water left to evaporate. At this point, the compressor can be stopped because continuing to run it would only waste energy without any further benefit in terms of water management. Thus, the method stops the compressor when it detects that the condensation and evaporation have balanced out. This ensures efficient operation by running the compressor only as long as needed to manage water condensation effectively.

[0016] In particular, the method of the present invention advantageously ensures that the compressor runs for a sufficient duration to evaporate any accumulated water, thereby preventing potential damage and maintaining operational efficiency. At the same time, the method seeks to avoid unnecessary energy consumption by stopping the compressor once a balance between condensation and evaporation is reached. Achieving this balance involves monitoring the operation of the compressor to precisely calculate an anticondensation phase parameter, thereby managing the operation of the compressor to both prevent water accumulation and conserve energy.

[0017] In particular, the input parameter may further comprise a temperature of the compressed air within the compressor In particular, the method further comprises the step of determining a duration and a degree by which the temperature of the compressor was below the calculated pressure dew point (Tdpres).

[0018] In particular, the method further comprises the step of activating or extending the operation of the compressor when the temperature of the compressor is below Tdpres for increasing the temperature above the dew point, thereby vaporizing any condensed moisture.

[0019] In particular, the method further comprises the steps of:

[0020] - requesting the actual speed of the compressor, wherein when there is no demand for the compressor to operate, activating a second signal indicating there is no active signal or command requesting the compressor to start or continue running.

[0021] In particular, the method further comprises

[0022] - stopping the compressor,

[0023] - setting the Bacc parameter value to the calculated anticondensation phase parameter value X, if the parameter value X is higher than zero, or

[0024] - setting the Bacc parameter value to zero, if X is smaller than zero.

[0025] In particular, the method further comprises:

[0026] - requesting the actual speed of the compressor;

[0027] - when there is a demand for the compressor to operate and the compressor is in an initial off-load phase, the first signal of the “request to run” flag remains activated,

[0028] - stopping the compressor;

[0029] - setting the Bacc parameter value to the calculated anticondensation phase parameter value X.

[0030] In particular, if Bacc (Backlog) is equal or higher than a first value Y1 , send / indicate a first warning (signal), e.g. to turn / turning on a yellow lamp, and / or initiating a dashboard message "allow the compressor to run". If Backlog is equal or higher than a second value Y2 indicate / send a second warning (signal), e.g. to turn / turning on a red lamp, and / or initiating / setting up a dashboard message "urgently allow the compressor to run".

[0031] In particular, the method further comprises:

[0032] - requesting the actual speed of the compressor;

[0033] - when there is a demand for the compressor to operate and the compressor is in a normal operation phase, the first signal of the “request to run” flag remains activated,

[0034] - stopping the compressor;

[0035] - setting the Bacc parameter value to the calculated anticondensation phase parameter value X.

[0036] In particular, if Bacc (Backlog) is equal or higher than a first value Y1 indicate / send a first warning (signal), e.g. to turn / turning on a yellow lamp, and / or initiating a dashboard message "allow the compressor to run.

[0037] The first and second values Y1 and Y2 are given values that are predetermined and validated based on the applications.

[0038] In particular, the method further comprises:

[0039] - recording data on the accumulation and evaporation of moisture within the compressor, and storing this data in a control unit to optimize future compressor operations.

[0040] In particular, the ambient temperature and relative humidity data are obtained from a CAN bus system of the vehicle. This, enables real-time environmental monitoring.

[0041] In particular, the pressure dew point (Tdpres) is recalculated at predefined intervals during the operation of the compressor operation to ensure continuous adjustment and optimal performance.

[0042] In particular, the method further comprises stopping the compressor only after confirming that all accumulated liquid water has evaporated and the internal temperature has been maintained above Tdpres for a sufficient period, or when there is no further need for compressed air, to avoid unnecessary energy consumption.

[0043] In particular, the method further comprises continuously recalculating the pressure dew point (Tdpres) during compressor operation, and adjusting the compressor's running time to maintain the temperature of the compressor above Tdpres.

[0044] Moreover, in another aspect, the present invention refers to a compressor system, in particular for a utility / commercial vehicle or a rail vehicle, wherein the compressor system is configured to perform a method according to one of the preceding claims.

[0045] Further details and advantages of the present invention are explained and described in more detail in the context of the embodiment as illustrated by the enclosed figures.

[0046] It is schematically shown:

[0047] Fig. 1 a block diagram of a method for preventing condensation in a compressor, in particular a compressor of an air supply / treatment system of a vehicle;

[0048] Fig. 2 a flow chart diagram of a process for calculating an anticondensation parameter X of the method shown in Fig. 1 ;

[0049] Fig. 3 a graph indicating the variation of the temperature of the compressor versus time; and

[0050] Fig. 4 a schematic view of a compressor.

[0051] In Fig. 1 a method 100 for preventing condensation in a compressor, in particular a compressor of an air supply / treatment system of a vehicle according to the present invention is shown.

[0052] The method 100 comprises the steps of starting the compressor and obtaining an actual speed and a nominal speed of the compressor.

[0053] The method 100 further comprises the step of starting an anticondensation phase monitoring for determining an anticondensation parameter X. The parameter X indirectly represents the duration and the degree by which the temperature was below the calculated (determined) pressure dew point Tpres. The calculation step of this parameter is described below in relation to Fig. 2.

[0054] The method 100 or the anticondensation phase monitoring further comprises the step of calculating pressure dew point temperature (Tdpres).

[0055] The method 100 further comprises the step activating 108 a signal or flag (referred to as "request to run") that commands the compressor operate until either the anticondensation parameter value X reaches 0 or the predefined Timeout limit is reached, whichever occurs first.

[0056] Alternatively, if a maximum allowed running time (referred to as "Timeout") is reached before X equals zero, the system should stop running.

[0057] Accordingly, the method 100 comprises setting 108 the "request to run" flag to 1 , and continuing operation until either the accumulated value X reaches 0 or the predefined Timeout limit is reached, whichever occurs first. The Timeout limit represent a maximum running time.

[0058] The method 100 further comprises the step of requesting speed 110. If the speed request equals zero, this indicates that there is no demand for the compressor or system to operate at any speed. This often occurs when the vehicle or system is turned off, as signified by "key off," meaning the ignition or power is off.

[0059] If the 'Request to run' = 0, this signifies that there is no active signal or command 112 requesting the compressor or system to start or continue running. In other words, the "request to run" flag is set to 0, indicating that the system is not required to operate.

[0060] Thereafter, the method 100 comprises stopping 114 the compressor and setting 116 the Bacc parameter value to the determined (calculated) anticondensation phase parameter X, if X is higher than zero. Alternatively, if X is smaller than zero setting 118 the Bacc parameter value to zero.

[0061] The method 100 further comprises:

[0062] - requesting the actual speed of the compressor;

[0063] - when there is a demand for the compressor to operate and the compressor is in an initial off-load phase, the first signal of the “request to run” flag remains activated,

[0064] - stopping the compressor;

[0065] - setting the Bacc parameter value to the calculated anticondensation phase parameter value X.

[0066] The method 100 may further comprise the step of sending / indicating warning signals as follows:

[0067] In particular, if Bacc (Backlog) is equal or higher than a first value Yi, send / indicate a first warning (signal), e.g. to turn / turning on a yellow lamp, and / or a dashboard message "allow the compressor to run.

[0068] If Backlog is equal or higher that a second value Y2 indicate / send a second warning (signal), e.g. to turn / turning on a red lamp, and / or initiating a dashboard message "urgently allow the compressor to run".

[0069] Alternatively, the method 100 further comprises

[0070] - requesting the actual speed of the compressor;

[0071] - when there is a demand for the compressor to operate and the compressor is in a normal operation phase, the first signal of the “request to run” flag remains activated,

[0072] - stopping the compressor;

[0073] - setting the Bacc parameter value to the calculated anticondensation phase parameter value X,

[0074] - indicating / initiating / sending a warning signal. In particular, if Bacc (Backlog) is equal or higher than a first value Yi, send / indicate a first warning (signal), e.g. to turn / turning on a yellow lamp, and / or initiating a dashboard message "allow the compressor to run.

[0075] Fig. 2 shows the step of calculating 107 an anticondensation phase parameter X using the formula.

[0076] Ti is the adjusted temperature determined by adding a C parameter value, measured at various conditions (as shown in table 1), to the calculated pressure dew point temperature Tdpres, with a maximum limit (Timax) of 97°C.

[0077] The term Actual_speed represents an actual speed of the compressor and the term Nominal_speed represents a nominal speed of the compressor.

[0078] Ticomp (x) is the instantaneous compressor internal temperature, measured x seconds after compressor start (time “x” indicated in Fig. 3 as time “t”). The temperature of the compressor is acquired at a frequency of 1 Hz. Other acquisition frequencies are however possible, with a corresponding adaptation of the calculation.

[0079] In particular, in cases where the compressor has a fixed speed, the ratio between actual and nominal equals 1 , and the anticondensation phase parameter X is calculated as follows:

[0080] The backlog represents an indirect quantification of the accumulated condensed water inside the compressor, recorded in the ECU memory. Initially, the backlog is set to zero. As the compressor operates, this value is updated to reflect ongoing condensation and is used in subsequent calculations to manage the anticondensation phase effectively. For example, when the compressor is off the value X equals the value of the backlog (Bacc).

[0081] The anticonception phase monitoring further comprises requesting to run the compressor, when conditions indicate the need to evaporate condensed water. To this end, a flag is raised to notify the Vehicle Electronic Control Unit (VECU) that the compressor should be activated. This request is based on the backlog and the current temperature conditions within the compressor.

[0082] The anticondensation phase monitoring further comprises the step of monitoring the compressor's runtime to manage a maximum running time.

[0083] To prevent excessive operation during the anticondensation phase, a maximum running time, known as TimeOut, is set for the compressor. This value is predetermined specific to the operational parameters of the phase. By monitoring the runtime of the compressor, it is ensured that the compressor does not exceed the Timeout limit, optimizing energy use while effectively managing condensation.

[0084] For example, the step of calculating the pressure dew point temperature is performed at the start of each charge cycle using inputs including system pressure, ambient pressure and relative humidity (RH).

[0085] The system pressure is set to the cut-off pressure plus 1 bar. Ambient temperature data is retrieved from the Controller Area Network (CAN), and relative humidity is assumed to be 95%.

[0086] In cases where the ambient temperature is not available on vehicle CAN, default value is used, such as 25°C.

[0087] In particular, it is further envisaged to obtain the relative humidity directly from CAN as a variable parameter or from a dedicated sensor. Fig. 3 shows a graph indicating the variation of the temperature of the compressor versus time (in seconds).

[0088] By way of the method according to the present invention the compressor stops once it achieves a balance between the amount of water that has condensed and the amount that has evaporated inside the compressor.

[0089] During operation, water vapor in the compressed air can condense into liquid when the temperature falls below the pressure dew point, creating a "condensing phase." As the compressor continues to run and its internal temperature rises, this condensed water eventually evaporates, entering the "evaporation phase."

[0090] The areas under the curve as showing Fig. 3 correspond to the total amount of water condensed and evaporated indicated as dotted pattern, respectively. When these two areas are equal, indicating that all the condensed water has evaporated, the compressor is stopped.

[0091] The method according to the present invention aims to achieve a balance where the total amount of water that has condensed inside the compressor (the surface of the condensing phase) equals the total amount of water that has been evaporated (the surface of the evaporation phase).

[0092] For example, the anticondensation phase monitoring (anticondensation function) may be conducted at every compressor start due to vehicle air demand by performing the following steps:

[0093] 1 . Calculate the pressure dew point temperature (once per charge cycle only, at start of charge cycle) based on the following information

[0094] - System pressure (cut-off pressure + 1 bar)

[0095] - Ambient temperature (available on CAN)

[0096] - 95% RH (for future updates consider RH as a parameter available on CAN) 2. Run the compressor permanently against overpressure valve or overflow valve (OFV) until the average internal air temperature reaches Ti:

[0097] - Average internal air temperature calculated since start of on-load phase, acquisition 1 Hz, CAN message “compressor temperature”

[0098] - Ti = calculated pressure dew point + C °C (parameter)

[0099] - Ti max = 97°C (parameter)

[0100] - Max running time 7 mins (parameter)

[0101] If the ambient temperature is not available on the vehicle CAN, a default value of 25°C (parameter set by default) is used.

[0102] Table 1 indicates the constant parameter C for calculating the parameter value Ti.

[0103] The above steps can be performed in various devices which are linked to the CAN bus such as an integrated Air Processing Unit (iAPU), an electronic Pneumatic Brake Controller (ePBC 12 bar) and electronic motors.

[0104] For ePBC driver speed demand should take precedence over the anticondensation function.

[0105] As another example, the anticondensation phase monitoring for ePBC at 15 bar (max pressure) may be conducted at every compressor start due to vehicle air demand by performing the following steps:

[0106] 1 . Calculate dew point temperature based on the following information: - System pressure (cut-off pressure 12,5 bar + / - 1 bar) (parameter) - 15 bar not to be considered

[0107] - Ambient temperature (available on CAN)

[0108] - 95% RH (for future updates consider RH as a parameter available on CAN)

[0109] 2. Run the compressor as requested by the system until cut off is reached.

[0110] 3. Then stop the air compressor and wait for a given time within the range of 5s to 15s before opening the supply line.

[0111] 4. After a certain time, for example in the range of 5 to 15s, e.g. 5s, 10s or 15s, restart the air compressor and run permanently at 2500rpm (except if low speed is demanded by the driver) against overflow valve until average on-load internal air temperature reaches Ti:

[0112] - Average on-load internal air temperature calculated since start of on-load phase (step 2), acquisition 1 Hz, CAN message “compressor temperature”

[0113] - Ti = calculated dew point + C °C (parameter) from table 1 Ti max = 97°C (parameter)

[0114] - Max running time 7 mins (parameter)

[0115] If there is a vehicle air demand while the compressor is running an extended load phase, stop the extended phase and restart at step 1 .

[0116] In particular, to avoid oil carryover after a 15 bar phase, the compressor must be stopped for a certain period, e.g. for a time about 5 to 15 seconds before opening the unloader due to the pressure differential (Ap) between 15 bar and the OFV.

[0117] Fig. 4 shows a schematic view of a compressor system 200 for which a method according to the present invention can be applied.

[0118] For example, the compressor system (or the compressor) 200 comprises a rotary compressor 202, in particular a rotary vane compressor, or a screw compressor. The compressor system 200 may include, for instance, an inlet port 204, a compression cell 206, an oil filter 208, and an outlet port 210.

[0119] The compressor system 200 further comprises a temperature measurement device 212 that is configured to measure the internal temperature of the compressed air as it enters an interior of the compressor housing chamber 214 from the compression cell (e.g., a vane cell).

[0120] To calculate the anticondensation parameter X, it is advantageous to determine the temperature of the compressed air after it exits the oil filter 208 but before it passes through the outlet port 210. This temperature is determined based on the measured temperature and the offset C.

[0121] For example, the offset C of the temperature can be determined, at least partially, under varying conditions on an experimental basis, i.e. by measuring the temperature preferably close to an exit of the compression cell 206, thus inside of the compressor housing chamber 214, and measuring the temperature at a point after the exit of the oil filter 208 and before / in front of the outlet port 210, e.g. by an only temporally integrated temperature sensor. Such limited amount of (experimental) measurement data may be further supplemented by an approximation curve and / or the like.

[0122] On basis of such (experimental) measurements and resulting data, a pre- configuration / predetermination of the offset C can be established / achieved.

[0123] Fig. 5 illustrates, on basis of and in reference to Fig. 2, the step of calculating 107 the anticondensation phase parameter X using an alternative version of the formula, in particular according to aspect 1 below: Such version of the formula for calculating the anticondensation phase parameter X is based on the circumstance and / or assumption, in comparison to the embodiment pursuant to Fig. 2, that the actual speed and nominal speed of the compressor are equal and thus result in the factor of 1 (“one”).

[0124] Thus, the present invention further refers to and comprises the following aspects in context of and connection with the foregoing disclosure and / or in combination with single features thereof:

[0125] Aspect 1 . A method (100) for preventing condensation in a compressor, in particular a compressor of an air treatment / supply system of a vehicle, the method comprising:

[0126] - starting (102) the compressor, when a speed request received (104);

[0127] - calculating (106) a pressure dew point temperature Tdpres of a compressed air based on input parameters, such as a system pressure, an ambient temperature and humidity,

[0128] - determining an adjusted temperature Ti by adding a predefined and / or a predeterminable temperature offset C to the calculated pressure dew point temperature Tdpres;

[0129] - calculating (107) anticondensation parameter X of an anticondensation phase using the formula: wherein Tcomp(t) represents an instantaneous internal temperature of the compressor at time t after starting the compressor, and Bacc represents a backlog parameter of condensation value (which refers to the accumulation of previously condensed water inside the compressor or historical data for condensed water);

[0130] - activating (108) a first signal indicating a request to run flag (an operation request signal) for the compressor to operate until either the anticondensation parameter X reaches a predefined threshold value, preferably zero, or a maximum operation time for the anticondensation phase is reached.

[0131] Aspect 2. The method (100) according to aspect 1 , characterized in that the method (100) further comprises:

[0132] - obtaining an actual speed and a nominal speed of the compressor, and

[0133] - adjusting the calculation of the anticondensation parameter X based on a scaling factor based on the ratio of the actual speed of the compressor to its nominal speed, as follows:

[0134] Aspect 3. The method (100) according to aspect 1 , characterized in that the method (100) further comprises operating the compressor in an anticondensation phase monitoring mode, wherein:

[0135] - the instantaneous internal temperature of the compressor is monitored at a predefined acquisition rate, preferably 1 Hz;

[0136] - the backlog parameter Bacc is retrieved preferably from memory of an electronic control unit;

[0137] - the first signal of request to run flag is activated to signal that the compressor should continue operating to evaporate condensed water.

[0138] Aspect 4. The method (100) according to any one of the preceding aspects, characterized in that the method (100) further comprises

[0139] - activating (110) a second signal, preferably by turning the compressor off, indicating that no request for compressor operation is present.

[0140] Aspect 5. The method (100) according to aspect 4, characterized in that the method (100) further comprises:

[0141] - checking whether the first signal of the request to run is still needed;

[0142] - if the continued operation of the compressor is not required, then:

[0143] - stopping (114) the compressor; and - setting (116) the backlog parameter Bacc to the calculated value of the parameter X if

[0144] X> 0, or

[0145] - setting (118) the backlog parameter Bacc to zero if X<0.

[0146] Aspect 6. The method (100) according to aspect 5, characterized in that

[0147] - storing the backlog parameter Bacc in memory of an electronic control unit and updating the backlog parameter Bacc.

[0148] Aspect 7. The method according to aspect 4, characterized in that the method (100) further comprises: checking whether the first signal of the request to run is still needed;

[0149] - if the continued operation of the compressor is required, then during initial off-load mode:

[0150] - stopping (124) the compressor;

[0151] - activating (122) a first signal of a request to run flag;

[0152] - comparing the backlog parameter Bacc against predefined thresholds, if the backlog parameter Bacc exceeds a first threshold Y1 , a first indicator is activated to signal continue compressor operation; and if the backlog parameter Bacc exceeds a second, higher threshold Y2, a second indicator is activated to signal urgent compressor operation.

[0153] Aspect 8. The method according to aspect 7, characterized in that the first indicator comprises a yellow lamp and a message "let compressor run", and the second indicator comprises red lamp and a message " urgently let compressor run".

[0154] Aspect 9. The method (100') according to aspect 4, characterized in that the method (100) further comprises:

[0155] - checking whether the first signal of the request to run is still needed;

[0156] - if the continued operation of the compressor is, then during normal operation mode: - stopping (130) the compressor;

[0157] - activating (132) a first signal of a request to run flag;

[0158] - setting (132) the Backlog parameter Bacc to the calculated anticondensation parameter X, wherein the Bacc parameter value comprises is limited to a maximum predefined value.

[0159] Aspect 10. The method according to aspect 9, characterized in that the backlog parameter Bacc exceeds a first threshold Y1 , a first indicator is activated to signal continue compressor operation, wherein the first indicator comprises a yellow lamp and a message "let compressor run".

[0160] Aspect 11 . The method (100) according to any one of the preceding aspects, characterized in that

[0161] - the pressure dew point temperature is recalculated at predefined intervals to adapt compressor operation to changing environmental and system conditions.

[0162] 12. The method (100) according to any one of the preceding aspects, characterized in that the system pressure is determined as a cut-off pressure plus a predefined offset value.

[0163] Aspect 13. The method (100) according to any one of the preceding aspects, characterized in that the ambient temperature is obtained from a network communication system, preferably a CAN bus system of a vehicle.

[0164] Aspect 14. The method (100) according to any one of the preceding aspects, characterized in that the humidity is defined as a predefined parameter or an externally provided input, or the humidity is obtained from a network communication system, preferably a CAN bus system of a vehicle.

[0165] Aspect 15. The method (100) according to any one of the preceding aspects, characterized in that the temperature offset C ranges from 3°C to 15°C, and the maximum operation time for the anticondensation ranges from 1 to 15 minute.

[0166] REFERENCE SIGNS

[0167] 100 Method

[0168] 102 Method step

[0169] 104 Method step

[0170] 106 Method step

[0171] 107 Method step

[0172] 108 Method step

[0173] 109 Method step

[0174] 110 Method step

[0175] 112 Method step

[0176] 114 Method step

[0177] 116 Method step

[0178] 118 Method step

[0179] 120 Method step

[0180] 122 Method step

[0181] 124 Method step

[0182] 126 Method step

[0183] 128 Method step

[0184] 130 Method step

[0185] 132 Method step

[0186] 200 Compressor system

[0187] 202 Rotary compressor

[0188] 204 Inlet port

[0189] 206 Compression cell

[0190] 208 Oil filter

[0191] 210 Outlet port

[0192] 212 Temperature measurement device

[0193] 214 Compressor housing chamber

Claims

CLAIMS1 . A method (100) for preventing condensation in a compressor, in particular a compressor of an air supply system of a vehicle, comprising:- starting (102) the compressor;- obtaining (104) an actual speed and a nominal speed of the compressor;- calculating (106) the pressure dew point (Tdpres) of the compressed air based on input parameters, wherein the input parameters comprise a system pressure and ambient conditions, including ambient temperature and / or relative humidity;- calculating (107) an anticondensation phase parameter (X) using the formula:wherein Ti is the adjusted temperature determined by adding a predetermined constant parameter value (C) to the calculated pressure dew point temperature (Tdpres), TComP(x) is the temperature of the compressor at time x (seconds after compressor start), Nactuai represents the actual speed of the compressor, Nominal represents the nominal speed of the compressor, Bacc represents an indirect quantification of the accumulated condensed water inside the compressor; and- activating (108) a first signal to command the compressor operate until either the anticondensation parameter value X reaches 0 or the predefined maximum running time limit is reached, whichever occurs first.

2. The method (100) according to claim 1 , characterized in that the method (100) further comprises:- determining a duration and a degree by which the temperature of the compressor was below the calculated pressure dew point (Tdpres).

3. The method (100) according to claims 1 or 2, characterized in that the method (100) further comprises:- requesting (109) to run the compressor, when conditions indicate the need to evaporate condensed water or- activating or extending the operation of the compressor when the temperature of the compressor is below Tdpres for increasing the temperature above the pressure dew point, thereby vaporizing any condensed moisture.

4. The method (100) according to any one of the preceding claims, characterized in that the method (100) further comprises- requesting (110) the actual speed of the compressor;- when there is no demand for the compressor to operate, activating (112) a second signal indicating there is no active signal or command requesting the compressor to start or continue running.

5. The method (100) according to claim 4, characterized in that the method (100) further comprises- stopping (114) the compressor,- setting (116) the Bacc parameter value to the calculated anticondensation phase parameter value X, if the parameter value X is larger than zero, or- setting (118) the Bacc parameter value to zero, if X is smaller than zero.

6. The method (100) according to any one of claims 1 to 3, characterized in that the method (100) further comprises:- requesting (110) the actual speed of the compressor, wherein when there is a demand for the compressor to operate (120) and the compressor is in an initial off-load phase, the first signal of the “request to run” flag remains activated (122),- stopping (124) the compressor;- setting (126) the Bacc parameter value to the calculated anticondensation phase parameter value X.

7. The method (100) according to any one of claims 1 to 3, characterized in that the method (100) further comprises:- requesting (110) the actual speed of the compressor, wherein when there is a demand for the compressor to operate (120) and the compressor is in a normal operation phase, the first signal of the “request to run” flag remains activated (128),- stopping (130) the compressor;- setting (132) the Bacc parameter value to the calculated anticondensation phase parameter value X,8. The method (100) according to any one of the preceding claims, characterized in that the method (100) further comprises:- recording data on the accumulation and evaporation of moisture within the compressor, and storing this data in a control unit to optimize future compressor operations.

9. The method (100) according to any one of the preceding claims, characterized in that the ambient temperature and / or relative humidity data are obtained from a CAN bus system of the vehicle.

10. The method (100) according to any one of the preceding claims, characterized in that the pressure dew point (Tdpres) is recalculated at predefined intervals during the operation of the compressor operation to ensure continuous adjustment and optimal performance.11 . Compressor system (200), in particular for a utility vehicle or a rail vehicle, wherein the compressor system (200) is configured to perform a method according to one of the preceding claims.

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