METHOD FOR DETECTING CONDENSATE FORMATION WHICH IS IMMINENT OR HAS ALREADY TAKEN PLACE ON/IN ELECTRIC MOTORS, AND METHOD FOR AVOIDING CORRESPONDING CONDENSATE FORMATION AND/OR FOR ELIMINATING/REDUCING CONDENSATE ON/IN ELECTRIC MOTORS

Abstract

A method is used to identify impending or previously occurring condensation on/in electric motors, in particular on/in electric motors as a component of fans or fan groups. It includes the following method steps: Determining component temperatures, preferably surface temperatures on the electronics, on/in the motor, on/in the fan, or on/in fan groups; Determining the dew point temperature or individual dew point temperatures on the electronics, in/on the motor, fan, or on/in fan groups; Comparing the respective component temperature with the respective dew point temperature and concluding a formation of condensation has already taken place or is imminent when the component temperature approaches the dew point temperature or when the dew point temperature is undershot. A further method serves to prevent the formation of condensate and/or to eliminate/remove condensate on/in electric motors, in particular on/in electric motors as a component of fans or fan groups. It includes the following method steps: Detecting an impending and/or previously occurring formation of condensate on or in the motor; and Initiating measures to prevent the formation of condensate and/or to eliminate/remove the condensate by means of passive or active measures.

Claims

1. A method for detecting impending or previously occurring formation of condensate on or in electric motors that are a component of a fan or fan group, comprising the following steps: determining a component temperatures on or in the motor, fan, or fan group, or an electronic component of the motor; determining a dew point temperature on or in the motor, fan, or fan group, or electronic component; and comparing the respective component temperature with the respective dew point temperature to determine whether or not a formation of condensation has already taken place or is imminent.

2. The method according to claim 1, wherein the component temperature is determined on the respective component.

3. The method according to claim 1, wherein the component temperature is determined at one or more critical locations.

4. The method according to claim 1, wherein the component temperature is determined from a calculation model of the motor, the fan, or the fan group.

5. The method according to claim 1, wherein one or more of the dew point temperatures are determined locally at potential condensation locations.

6. The method according to claim 1, wherein the dew point temperature is measured by means of hygrometric methods.

7. The method according to claim 1, wherein the dew point temperature is determined from an actual vapor pressure, and the actual vapor pressure is determined from a temperature-dependent local saturation vapor pressure and a local ambient air humidity of the component.

8. The method according to claim 1, wherein the step of determining the dew point temperature comprises applying pressure-related calculation rules for a low-pressure/high-pressure application.

9. The method according to claim 7, wherein the component temperature is measured locally using a temperature sensor.

10. The method according to claim 7, further comprising the step of transmitting the component temperature from an internal or decentralized measuring unit to an evaluation unit.

11. The method according to claim 7, wherein the component temperature is determined indirectly by means of a calculation model.

12. The method according to claim 7, wherein the ambient air humidity of the component is measured using a moisture sensor.

13. The method according to claim 11, wherein a time factor or a calculation model is used to determine the ambient air humidity.

14. A method for removing and preventing condensate from forming on electric motors, comprising the following method steps: detecting an impending and/or previously occurring formation of condensate on or in the motor according to the method of claim 1; and initiating measures to remove and prevent the formation of condensate by means of passive or active measures.

15. The method according to claim 14, wherein the measures include ventilation and aeration by rotating a rotor in the motor.

16. The method according to claim 14, wherein the measures include starting the fan.

17. The method according to claim 14, wherein the measures include adjusting a motor speed.

18. The method according to claim 14, wherein the measures include heating the motor, a motor component, or external electronics.

19. The method according to claim 14, further comprising the step of generating a warning message before or upon initiating the measures.

Description

[0059] There are then various options for designing and refining the teaching of the present disclosure in an advantageous manner. To this end, reference is made, on the one hand, to the claims relating back to claim 1 and, on the other hand, to the subsequent explanation of a preferred exemplary embodiment of the disclosure by means of the drawing. In conjunction with the explanation of the preferred exemplary embodiment of the disclosure by means of the drawing, preferred embodiments and enhancements of the teaching are also generally explained. The drawings show the following:

[0060] FIG. 1 a schematic, sectional view of an exemplary embodiment of a motor, during the operation of which the method according to the disclosure can be used; and

[0061] FIG. 2 a flowchart of the sequence of the method according to the disclosure with the individual method steps.

[0062] FIG. 1 shows, in a sectional drawing, a typical electric motor in an external rotor design, as it is used as a drive unit in fans/fan groups. The familiarity with such electric motors is assumed, so that a detailed explanation is not necessary at this juncture.

[0063] In the case of the electric motor with the external rotor design, it is essential that the stator 1 is arranged about the motor axis 2 and the rotor 3 is arranged about the stator 1, so as to rotate thereabout.

[0064] The stator 1 is positioned on a bearing tube 4 which, together with a side wall 5, is part of a housing 6, which can be divided into different regions inside.

[0065] The rotor 3 is surrounded by a wall 7, which rotates jointly with the rotor 3. This means that a fan impeller, which is not shown in FIG. 1, can be attached in a rotationally fixed manner using suitable means.

[0066] A microprocessor 8 is provided inside the housing 6, with a communication line 9 exiting from the microprocessor toward the outside of the housing 6.

[0067] Furthermore, a sensor 10, specifically a moisture sensor, is arranged inside the housing 6. It is also conceivable to provide a temperature sensor, which is not shown, within the housing 6.

[0068] The measurement data obtained via the sensor 10 are sent to the microprocessor 8 and can be supplied to external electronics or an evaluation unit via the communication line 9, as discussed in the general part of the description. Furthermore, measurement data from an external measurement unit can be transmitted to the motor via the communication line 9 (wired or wireless), so that these data are evaluated by the microprocessor 8. If an external evaluation unit is used to determine the risk of condensation, it is also the particular evaluation unit which initiates the protective mechanisms via the communication line 9. The data flow is primarily intended in the direction of the motor, according to which an external measurement is supplied to the motor, for example. It is conceivable to have the condensate detection and condensate prevention carried out, for example, by an external device (gateway, PLC, cloud, etc.).

[0069] FIG. 2 shows, within the scope of a flowchart, the sequence of the method according to the disclosure for detecting and preventing the formation of condensate.

[0070] In this case, the ambient temperature of the motor/fan to be monitored or a complete fan group is first measured or determined. According to the general description, a thermal model using a digital twin can be utilized.

[0071] The ambient air humidity of the motor/fan to be monitored (or a complete fan group) is determined. The dew point temperature or individual dew point temperatures are then calculated in critical areas or on critical components in or on the motor.

[0072] Surface temperatures of the individual components of the motor or fan are calculated or measured. If the component temperature or surface temperature is almost at the dew point temperature or below the dew point temperature, an entry can be made in an event memory, for example, and optional protective functions can be initiated. If this is not the case, a suitable protective function can be activated, almost automatically, to prevent the dew point from dropping to below the lower limit.

[0073] To avoid repetition, reference is otherwise made to the general description in which the method is discussed in detail.

[0074] With regard to other advantageous designs of the teaching according to the disclosure, reference is made, to avoid repetition, to the general part of the description and to the attached claims.

[0075] Finally, express reference is made regarding the fact that the previously described exemplary embodiment of the teaching according to the disclosure is only meant to explain the claimed teaching; however, it is not limited to this exemplary embodiment.

LIST OF REFERENCE NUMERALS

[0076] 1 Stator [0077] 2 Motor axis [0078] 3 Rotor [0079] 4 Bearing tube [0080] 5 Wall (stator) [0081] 6 Housing [0082] 7 Wall (rotor) [0083] 8 Microprocessor [0084] 9 Communication line [0085] 10 Sensor, humidity sensor