Self-powered detection sensor and method for identifying rotor eccentricity faults

Abstract

The application discloses a self-powered detection sensor for identifying rotor eccentricity fault and a method, relates to the technical field of sensors, and discloses the sensor which comprises a sensor shell and a supporting seat arranged at the bottom of the sensor shell. The sensor shell can be sleeved on a rotor transmission shaft. A plurality of groups of copper film electrodes are coaxially arranged in the sensor shell in a ring shape and at equal intervals from outside to inside. A flywheel in a circular shape and capable of being arranged around the rotor transmission shaft is arranged in the sensor shell. A plurality of groups of dielectric layers equal in number to the copper film electrodes are arranged on the flywheel and capable of being in contact with the copper film electrodes. The sensor for identifying the rotor eccentricity fault is simple in structure, convenient to install, low in cost, and does not need external power supply, is favorable for large-scale application, can simultaneously detect and identify the eccentricity degree and the eccentricity direction, is high in identification precision, and has a wide application range.

Description

Technical Field

[0001] This invention relates to the field of sensor technology, and specifically to a self-powered detection sensor and method for identifying rotor eccentricity faults. Background Technology

[0002] The operating environment of rotor systems is complex and susceptible to factors such as high-frequency vibration and alternating loads, leading to frequent failures. Accurate identification of rotor eccentricity faults is crucial for minimizing operating costs and improving the reliability and safety of rotor systems. Many existing methods exist for detecting rotor eccentricity faults, including vibration signal analysis, current characteristic analysis, and acoustic emission detection. However, these methods generally suffer from low detection accuracy, complex external detection systems, and high costs. Triboelectric nanogenerators, as a novel nanoenergy technology, convert mechanical energy from the surrounding environment into electrical energy through contact electrification and electrostatic induction, enabling the power supply of various low-power devices. Furthermore, triboelectric nanogenerators can adapt to various frequencies and complex forms of mechanical motion, generating electrical signals that reflect changes in external excitation. Using triboelectric nanogenerators for rotor system eccentricity fault detection enables self-powered detection.

[0003] Existing rotor eccentricity fault detection functions based on triboelectric nanogenerators are limited in scope and cannot simultaneously identify the degree and direction of eccentricity. This leads to increased costs for troubleshooting and subsequent maintenance, hindering large-scale industrial applications. Summary of the Invention

[0004] Therefore, the present invention aims to provide a self-powered detection sensor and method for identifying rotor eccentricity faults, which can achieve qualitative and quantitative detection of high-precision rotor eccentricity faults under low-cost conditions.

[0005] To solve at least one of the above-mentioned technical problems, the technical solution provided by the present invention is:

[0006] A self-powered detection sensor for identifying rotor eccentricity faults is provided. The sensor includes a sensor housing and a support base disposed at the bottom of the sensor housing. The sensor housing can be fitted onto the rotor drive shaft. Inside the sensor housing, multiple sets of copper film electrodes are arranged coaxially and equally spaced from the outside to the inside, and a flywheel with a circular shape that can be arranged around the rotor drive shaft is provided. The flywheel is provided with multiple sets of dielectric layers with the same number as the copper film electrodes, and the dielectric layers can contact the copper film electrodes.

[0007] One embodiment of the present invention is that the copper film electrode is composed of two sets of arc-shaped electrode sheets arranged at intervals.

[0008] One embodiment of the present invention is that the number of copper film electrodes is four or more.

[0009] One embodiment of the present invention is that the dielectric layer is a U-shaped insulating film, the tip of which can contact the copper film electrode.

[0010] Furthermore, the dielectric layer is made of one of polytetrafluoroethylene, polyvinylidene fluoride, or fluoroethylene propylene copolymer, and the film thickness is 50μm~200μm.

[0011] One embodiment of the present invention is that a wire groove is provided between the copper film electrode and the sensor housing.

[0012] One embodiment of the present invention is that the sensor housing is detachably provided with a side sealing cover and a shaft adapter on one side along its axial direction.

[0013] One embodiment of the present invention is that the sensor housing is provided with a first sliding oil seal and a second sliding oil seal on both sides along its axial direction to maintain a mechanical seal with the rotor drive shaft.

[0014] Furthermore, the present invention also provides a method for identifying rotor eccentricity faults, which uses the above-mentioned device for identification and includes the following steps:

[0015] Step S1: According to the test requirements, copper film electrodes and dielectric layers with a specific number and spacing angle are set in an annular space between the flywheel and the sensor housing;

[0016] Step S2: Coaxially mount the sensor housing onto the rotor drive shaft, so that the flywheel is in fixed contact with the rotor drive shaft, and electrically connect the copper film electrode to the external electrical signal measuring device of the sensor;

[0017] Step S3: When the rotor rotates, the electrical signal measurement device outside the sensor collects the electrical signal generated between the dielectric layer and the copper film electrode driven by the flywheel. Based on different independent measurement points, the eccentricity of the rotor is determined by the output result of the electrical signal.

[0018] The technical effects achieved by this invention are:

[0019] 1. The eccentricity fault sensor in this invention has a simple structure, is easy to install, has low cost, and does not require an external power supply, which is beneficial for large-scale application.

[0020] 2. The sensor of this invention can simultaneously detect and identify the degree and direction of eccentricity, and has high identification accuracy, thus having a wide range of applications.

[0021] 3. The sensor and corresponding method for identifying rotor eccentricity faults proposed in this invention provide a theoretical basis for identifying eccentricity faults in multi-span rotor systems, which helps guide the identification of eccentricity faults in similar situations and the regular maintenance of mechanical equipment. Attached Figure Description

[0022] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained from these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the sensor being installed in the rotor system according to an embodiment of the present invention;

[0024] Figure 2 This is an exploded view of the sensor in this invention;

[0025] Figure 3 This is a schematic diagram of the internal structure of the sensor in this invention;

[0026] Figure 4 This is a distribution map of independent measurement points in an embodiment of the present invention;

[0027] Figure 5 This is a schematic diagram of the sensor's internal structure when the rotor experiences an eccentricity fault in an embodiment of the present invention;

[0028] Figure 6 This is a fitting curve of open-circuit voltage versus rotational speed in an embodiment of the present invention;

[0029] Figure 7 This is a fitting curve of open-circuit voltage and eccentricity fault degree in an embodiment of the present invention;

[0030] Figure 8 This is a diagram showing the open-circuit voltage results of the sensor when rotor-1 and rotor-2 are eccentric in the same direction in an embodiment of the present invention.

[0031] Figure 9 This is a diagram showing the open-circuit voltage results of the sensors when rotor-1 and rotor-2 are eccentric in opposite directions in an embodiment of the present invention.

[0032] Figure 10 This is a diagram showing the open-circuit voltage results of the sensor when rotor-1 and rotor-2 are eccentric along random non-collinear directions in an embodiment of the present invention.

[0033] In the figure, 1-sensor, 100-sensor housing, 101-support base, 102-side sealing cover, 103-first sliding oil seal, 104-second sliding oil seal, 105-shaft adapter, 106-flywheel, 107-dielectric layer, 108-copper film electrode, 109-wire groove, 108a-A copper film electrode sheet, 108b-B copper film electrode sheet, 2-rotor drive shaft, a-rotor eccentricity fault angle, b-eccentric shaft. Detailed Implementation

[0034] The present invention will be further described in detail below with reference to the embodiments and accompanying drawings.

[0035] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention.

[0036] A self-powered detection sensor for identifying rotor eccentricity faults, such as Figure 2 As shown, sensor 1 includes a sensor housing 100 and a support base 101 disposed at the bottom of the sensor housing 100. The sensor housing 100 can be fitted onto the rotor drive shaft 2. Inside the housing, multiple sets of copper film electrodes 108 are arranged coaxially from the outside to the inside, and a flywheel 106 with a circular shape that can be arranged around the rotor drive shaft 2. The flywheel 106 is provided with multiple sets of dielectric layers 107, the same number as the copper film electrodes 108, and the dielectric layers 107 can contact the copper film electrodes 108.

[0037] In an embodiment of the present invention, the copper film electrode 108 is composed of two sets of arc-shaped electrode sheets spaced apart, such as... Figure 3 As shown, they are copper film electrode sheet A 108a and copper film electrode sheet B 108b, respectively. The intersection of the axis of symmetry of the two sets of arc-shaped electrode sheets and the rotor drive shaft 2 is the independent measurement point corresponding to the copper film electrode 108. The dielectric layer 107 is U-shaped, and its tip can contact the copper film electrode sheet A 108a and copper film electrode sheet B 108b that make up the copper film electrode 108. The other side of the U-shaped structure is fixed to the flywheel 106 in the form of a double fulcrum. It can be seen that the part used for friction is actually the tip of the dielectric layer 107.

[0038] In actual setup, sensor 1 can be positioned at any location on rotor drive shaft 2 as needed. It is adapted to rotor drive shafts 2 of different specifications via shaft adapter 105. The rotor drive shaft 2 passes through sensor 1, which is formed by sensor housing 100 and side sealing cover plate 102, and the flywheel 106 inside sensor 1. The first sliding oil seal 103 and the second sliding oil seal 104 on both sides of sensor 1 maintain a mechanical seal between sensor 1 and rotor drive shaft 2. This mechanical seal prevents lubricating grease on rotor drive shaft 2 from entering sensor 1 and affecting detection accuracy. When rotor drive shaft 2 rotates, it drives flywheel 106 to rotate synchronously, causing dielectric layer 107 to rotate synchronously with flywheel 106, thereby generating friction between dielectric layer 107 and copper film electrode 108.

[0039] The dielectric layer 107 should be made of an insulator, typically a material with low elastic modulus and high electronegativity, such as polytetrafluoroethylene, polyvinylidene fluoride, or fluoroethylene propylene copolymer. To ensure its triboelectric effect, it is a U-shaped insulating film with its tip in contact with the copper film electrode 108, and the film thickness is 50μm~200μm.

[0040] Based on this, the friction generated by the flywheel 106 will produce positive charges on the copper film electrode 108, while the dielectric layer 107 will produce negative charges, ultimately generating an AC voltage signal. This signal can be transmitted to an external electrical signal detection device for analysis via wires embedded in the wire groove 109 between the copper film electrode 108 and the sensor housing 100. It reflects the dynamic contact situation of the contact area. In other words, during the friction process, the open-circuit voltage corresponding to each independent measurement point will change with the change of the effective contact area of ​​the positive and negative triboelectric layers (i.e., the copper film electrode 108 and the dielectric layer 107). The detection principle is as follows:

[0041] Since the voltage on the surface of dielectric layer 107 is variable and cannot be considered a single node, it is assumed that the contact area length between dielectric layer 107 and copper film electrode 108 is... l Here, dielectric layer 107 is divided into countless infinitesimal elements d. k The triboelectric charge density of each micro-element is - σ Under short-circuit conditions, the surface charge dQ of copper film electrode sheet 108a in copper film electrode 108... A The surface charge dQ of the copper film electrode 108b B The expressions then satisfy equations (1) and (2) respectively:

[0042] (1)

[0043] (2)

[0044] in, ωIt is the width of the copper film electrode 108. C A (k) It is the capacitance between the surface of dielectric layer 107 and copper film electrode 108a. C B (k) It is the surface of dielectric layer 107 and copper film electrode sheet 108b.

[0045] According to the principle of electrostatic field superposition, by superimposing all electrostatic regions on the surface of dielectric layer 107, the total charge on the surfaces of copper film electrode 108a (A) and copper film electrode 108b (B) can be obtained as shown in equations (3) and (4), respectively:

[0046] (3)

[0047] (4)

[0048] The contact separation process between dielectric layer 107 and copper film electrode 108 drives the reciprocating motion of electrons between the two electrode plates, from which the total charge transfer Q can be derived. sc,final The calculation formula is shown in formula (5):

[0049] (5)

[0050] Where x represents the displacement of dielectric layer 107, and g represents the gap length between the two copper film electrodes 108. Theoretically, the charge transfer efficiency (η) of the triboelectric nanogenerator is... CT It can reach 100%, that is, Q. sc The maximum open-circuit voltage (V) on the copper film electrode 108 is reached at σωl. oc,max ) is the maximum short-circuit charge (Q) sc,max The function of capacitance (C0) is shown in equation (6):

[0051] (6)

[0052] The above equation shows that the open-circuit voltage amplitude of the triboelectric nanogenerator depends on the effective contact area between the dielectric layer 107 and the copper film electrode 108. Therefore, rotor eccentricity fault information can be effectively extracted from the open-circuit voltage distribution at the independent measurement points of sensor 1, and the actual eccentricity direction and degree can be determined through vector decomposition and synthesis of the electrical output.

[0053] The rotor eccentricity fault identification method based on the above sensors is as follows:

[0054] Step S1: According to the test requirements, copper film electrodes 108 and dielectric layers 107 with a specific number and spacing angle are arranged in an annular interval between the flywheel 106 and the sensor housing 100. The number and distribution angle of the copper film electrodes 108 and the corresponding dielectric layers 107 can be arbitrarily set according to the actual test requirements, thereby arbitrarily setting the independent measurement points of the sensor 1.

[0055] The eccentricity of the rotor during rotation can be reflected on the drive shaft where the rotor is located. As long as the state of the rotor drive shaft 2 is determined, the eccentricity of the rotor can be indirectly obtained. Therefore, the sensor 1 can be set at any position on the shaft that drives the rotor to rotate.

[0056] Step S2: Coaxially mount the sensor housing 100 onto the drive shaft of the rotor to be tested, so that the flywheel 106 is in fixed contact with the rotor drive shaft 2, and electrically connect the copper film electrode 108 to the external electrical signal measuring device of the sensor 1. Each set of copper film electrodes 108 and the sensor 1 are connected to the external electrical signal measuring device through independent wires, thereby obtaining multiple sets of independent measurement points.

[0057] Generally speaking, the number of copper film electrodes 108 and the corresponding number of dielectric layers 107 can be set arbitrarily. The more copper film electrodes 108 there are, the more test points can be obtained, and the more comprehensive the data collected. However, the resistance encountered by the flywheel 106 when rotating is also greater, which will affect the detection accuracy. Therefore, the number of copper film electrodes 108 and dielectric layers 107 should be set according to the actual situation. Considering the basic requirements of measurement accuracy, the number of copper film electrodes 108 should be at least 4 sets.

[0058] Step S3: As the rotor rotates, an external electrical signal measuring device collects the electrical signals generated between the dielectric layer 107 and the copper film electrode 108 driven by the flywheel 106, determining the reference independent measurement point. The open-circuit voltage amplitude of sensor 1 depends on the effective contact area between the dielectric layer and the electrode. Misalignment fault information can be effectively extracted from the open-circuit voltage distribution of multiple independent measurement points of sensor 1. The actual misalignment direction and degree are determined through vector decomposition and synthesis of the electrical output, thereby judging the eccentricity of the rotor relative to the reference independent measurement point.

[0059] Example: To comprehensively study the fault detection capability of the above-mentioned sensing and detection equipment when the rotor system transitions from a single-span configuration to a double-span configuration, eccentric faults of different degrees and directions were introduced into the rotor system. The exact location of the eccentric faults was precisely simulated using metal shims and a micrometer. Taking the detection of a double-span rotor system with more complex fault states as an example, two sets of test rotors, numbered Rotor-1 and Rotor-2, were subjected to six different states of eccentric faults along the same, opposite, and randomly non-collinear directions. The testing device was as follows: Figure 1 As shown, since sensor 1 can be set on the rotor drive shaft 2 of the driving rotor to test the eccentricity, for a multi-rotor structure, multiple sets of sensor 1 can be set at any position on the drive shaft of the driving rotor. In this embodiment, a coupling is used to connect the two shafts of the two rotors to the same motor. On this basis, two sets of sensor 1, numbered M1 and M2, are set on the rotor drive shaft 2 of the two test object rotors, numbered rotor-1 and rotor-2, respectively, to detect them. The external electrical signal measuring device connected to the copper film electrode 108 during the test consists of an electrometer, a computer and a relay, which can realize the cyclic acquisition of multi-channel output voltage.

[0060] Both M1 and M2 are tested using 8 independent measurement points coded counterclockwise from EP-1 to EP-8, as detailed below. Figure 4 As shown, there are eight groups of copper film electrodes 108 and eight groups of dielectric layers 107, distributed at 45° intervals. See also... Figure 5 eccentric direction ( The definition is: within the interval of independent measurement points, the angle of counterclockwise rotation from the independent measurement point EP-i to the eccentric axis b. θ (Right now Figure 5 The direction vector corresponding to the rotor eccentricity fault angle a). In this embodiment, both sets of rotors select the independent measurement point EP-1 as the reference measurement point, and rotate counterclockwise at intervals to obtain the remaining independent measurement points EP-i. The degree of eccentricity fault ( λ i The displacement of the rotor in the eccentric direction is defined as the displacement of the rotor relative to the reference measurement point when the rotor is eccentric. To quantitatively analyze rotor misalignment faults, the following systems were established: Figure 6 and Figure 7 The fitting curves of open-circuit voltage with respect to rotational speed and degree of eccentricity fault are shown in equations (7) and (8):

[0061] (7)

[0062] (8)

[0063] in, V oc It is open-circuit voltage. n in It is the input speed of the rotor system.

[0064] The eccentricity direction can be represented by the vector of the two independent measurement points with the highest output voltage, as shown in equation (9):

[0065] (9)

[0066] in, It is the eccentric vector of independent measurement point 1. It is the eccentric vector of independent measurement point 2. α i1 It is the eccentricity angle of independent measurement point 1. α i2 It is the eccentricity angle of independent measurement point 2.

[0067] For any two adjacent independent measurement points, the eccentricity direction can be expressed as shown in equation (10):

[0068] (10)

[0069] in, λ i1 The eccentricity distance of independent measurement point 1, λ i2 This is the eccentricity distance of the independent measurement point 2.

[0070] By combining the two vectors in equation (10), a vector in the rotor eccentricity direction can be obtained. The specific expression is shown in equation (11):

[0071] (11)

[0072] in, θ It is the eccentricity fault angle of the rotor.

[0073] Based on this, the degree and angle of rotor eccentricity fault can be expressed as equations (12) and (13), respectively:

[0074] (12)

[0075] (13)

[0076] in, k The angle variable represents the number of specific angles that differ between the eccentric position and the selected independent reference measurement point, and is determined by the coding sequence of the independent measurement point and the angle between adjacent independent measurement points.

[0077] When rotor-1 and rotor-2 are eccentric in the same direction, the angle between their eccentric directions projected axially onto the plane is 0°. The test results of the two sets of sensors 1 for rotor-1 and rotor-2 are as follows: Figure 8As shown, the maximum peak voltages at measurement points EP-1 and EP-2 in M1 are 13.27V and 13.43V respectively, higher than other measurement points, indicating that the eccentricity direction is between EP-1 and EP-2. Similarly, the maximum peak voltages at measurement points EP-1 and EP-2 in M2 are 14.96V and 15.18V respectively, higher than other measurement points, again indicating that the eccentricity direction is between EP-1 and EP-2. Due to the superposition of fault vectors in the same direction, the misalignment directions of rotor-1 and rotor-2 can be calculated as follows: and The fault degrees were 0.204mm and 0.606mm, respectively.

[0078] When rotor-1 and rotor-2 are eccentric in opposite directions, the angle between their eccentric directions projected axially onto the plane is 180°. The test results of the two sets of sensors 1 for rotor-1 and rotor-2 are as follows: Figure 9 As shown, the maximum peak voltages at measuring points EP-3 and EP-4 in M1 are 14.87V and 14.57V respectively, higher than other measuring points, indicating that the eccentricity direction is between EP-3 and EP-4. Similarly, the maximum peak voltages at measuring points EP-7 and EP-8 in M2 are 14.88V and 14.58V respectively, higher than other measuring points, indicating that the eccentricity direction is between EP-7 and EP-8. Based on the principle of vector superposition, the misalignment directions of rotor-1 and rotor-2 are respectively... and The fault degrees were 0.502mm and 0.507mm, respectively.

[0079] When the eccentric directions of rotor-1 and rotor-2 are random and non-collinear, the angle between their eccentric directions projected axially onto the plane is any angle other than 0° and 180°. The test results of the two sets of sensors 1 for rotor-1 and rotor-2 are as follows: Figure 10 As shown, the maximum peak voltages at measuring points EP-4 and EP-5 in M1 are 14.90V and 14.91V respectively, higher than other measuring points, indicating that the eccentricity direction is between EP-4 and EP-5. Similarly, the maximum peak voltages at measuring points EP-1 and EP-2 in M2 are 15.46V and 15.54V respectively, higher than other measuring points, indicating that the eccentricity direction is between EP-1 and EP-2. Based on the principle of vector superposition and the formula, the misalignment directions of rotor-1 and rotor-2 are calculated as follows: and The fault degrees were 0.546mm and 0.774mm, respectively.

[0080] Furthermore, for a rotor system with multiple rotors driven by a common motor via a coupling, the fault results obtained by the above method are all the displacement and direction of the rotor relative to the motor. However, if it is necessary to determine the fault results between two rotors, it can be calculated from the fault results between the two rotors and the motor respectively.

[0081] It can be seen that the maximum peak voltage monitored by each independent measurement point of sensor 1 will change accordingly with the eccentric fault, thus allowing sensor 1 to intuitively and accurately reflect the fault information of the rotor's eccentric direction and degree of eccentricity, and to achieve accurate identification of eccentric faults in multi-span rotor systems.

[0082] In the description of this invention, it should be noted that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. They should not be construed as limitations on this invention.

[0083] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the embodiments of the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A self-powered detection sensor for identifying rotor eccentricity faults, characterized in that, The sensor (1) includes a sensor housing (100) and a support base (101) disposed at the bottom of the sensor housing (100). The sensor housing (100) can be fitted onto the rotor drive shaft (2). Inside the sensor housing, multiple sets of copper film electrodes (108) are arranged coaxially from the outside to the inside, and a flywheel (106) with a circular shape and capable of being arranged around the rotor drive shaft (2). The flywheel (106) is provided with multiple sets of dielectric layers (107) with the same number as the copper film electrodes (108). The dielectric layers (107) can contact the copper film electrodes (108). The dielectric layers (107) are U-shaped insulating films with their tips in contact with the copper film electrodes (108). The open-circuit voltage amplitude of the sensor (1) depends on the effective contact area between the dielectric layer and the electrode.

2. The self-powered detection sensor for identifying rotor eccentricity faults according to claim 1, characterized in that: The copper film electrode (108) consists of two sets of arc-shaped electrode sheets spaced apart.

3. The self-powered detection sensor for identifying rotor eccentricity faults according to claim 1, characterized in that: The number of copper film electrodes (108) is more than 4 groups.

4. The self-powered detection sensor for identifying rotor eccentricity faults according to claim 1, characterized in that: The dielectric layer (107) is made of one of polytetrafluoroethylene, polyvinylidene fluoride, or fluoroethylene propylene copolymer, and the film thickness is 50μm~200μm.

5. A self-powered detection sensor for identifying rotor eccentricity faults according to claim 1, characterized in that: A wire groove (109) is provided between the copper film electrode (108) and the sensor housing (100).

6. The self-powered detection sensor for identifying rotor eccentricity faults according to claim 1, characterized in that: The sensor housing (100) is detachably provided with a side sealing cover (102) and a shaft adapter (105) on one side along its axial direction.

7. A self-powered detection sensor for identifying rotor eccentricity faults according to claim 1, characterized in that: The sensor housing (100) is provided with a first sliding oil seal (103) and a second sliding oil seal (104) on both sides along its axial direction to maintain a mechanical seal with the rotor drive shaft (2).

8. A method for identifying rotor eccentricity faults, characterized in that, Identification using any one of the devices described in claims 1-7 includes the following steps: Step S1: According to the test requirements, copper film electrodes (108) and dielectric layers (107) with a specific number and spacing angle are arranged in an annular interval between the flywheel (106) and the sensor housing (100). Step S2: Coaxially mount the sensor housing (100) onto the rotor drive shaft (2) so that the flywheel (106) is in fixed contact with the rotor drive shaft (2), and electrically connect the copper film electrode (108) to the electrical signal measuring device outside the sensor (1); Step S3: When the rotor rotates, the electrical signal measurement device outside the sensor (1) collects the electrical signal generated between the dielectric layer (107) driven by the flywheel (106) and the copper film electrode (108). Based on different independent measurement points, the eccentricity of the rotor is determined by the output result of the electrical signal.

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