Motor Remaining Life Judgment System

Abstract

To provide a system for determining the remaining life of a motor which can determine the remaining life of a motor on the basis of thermal degradation of a member which covers the coil of the motor or a member which attaches the core and the coil to each other.SOLUTION: The present invention has a controller 12 for determining the degradation of a motor, and the controller 12 includes: a first acquisition unit 16 for acquiring the impedance between a coil 5 and a core 4; an estimation unit 17 for estimating the total heat input amount for the motor on the basis of the level of the impedance between the coil 5 and the core 4; and a determination unit 18 for determining the remaining life on the basis of the thermal degradation of the motor on the basis of the total heat input amount estimated by the estimation unit 17.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a system for determining the remaining life of a motor due to thermal degradation.

Background Art

[0002] Patent Document 1 describes a system for diagnosing precursors such as peeling at the interface between the energized part of an electrical device and the resin mold and cracking of the resin mold. This system measures the stress applied to the surface of the resin mold with a stress measuring device using synchrotron radiation such as X-rays, and from the stress applied to the surface of the resin mold and the function of the stress at the surface part and the stress at the interface part obtained in advance with a test piece or the like, the stress applied to the interface part between the energized part and the resin mold is obtained, and further, from the stress applied to the interface part, the equivalent elapsed years are obtained.

[0003] Patent Document 2 describes a method for predicting the remaining life of a bearing configured to predict the remaining life of a bearing according to the fatigue of the bearing without destroying the bearing. This method for predicting the remaining life detects the impedance of the load surface where loads act, such as the raceway surface of the outer ring, the raceway surface of the inner ring, and the rolling surface of the rolling elements, after use of the bearing, with an eddy current measuring device, and compares the detected impedance with the impedance before use of the bearing or the impedance of a part other than the load surface to predict the remaining life of the bearing.

[0004] Patent Document 3 describes a method for diagnosing the remaining life of a control wiring of a substation equipment configured to diagnose the remaining life of the control wiring without destroying the control wiring. This method for diagnosing the remaining life first irradiates white light to each of a new wiring and a deteriorated wiring (measurement target product), and performs spectral analysis on the reflected light. Then, the reflectance of the new product and the deteriorated product is obtained respectively, and the reflectance difference between two predetermined wavelengths among the obtained reflectances is compared, and the remaining life is diagnosed based on the reflectance difference.

Prior Art Documents

Patent Documents

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-146252 [Patent Document 2] International Publication No. 2011 / 074654 [Patent Document 3] Japanese Patent Application Laid-Open No. 2011-007662 [Summary of the Invention] [Problems to be Solved by the Invention]

[0006] The diagnostic system described in Patent Document 1 measures the stress of a resin mold using synchrotron radiation such as X-rays in order to diagnose the number of years of use without destroying the electrical equipment, and based on the measurement results, determines the stress at the interface between the energized part, which is the inner part of the resin mold, and the resin mold. That is, among the parameters detectable from the outer surface of the electrical equipment, a parameter having a correlation with the target part is selected, and the deterioration of the target part is determined by measuring the selected parameter.

[0007] Similarly, in the remaining life prediction method described in Patent Document 2, the impedance of a component is measured from the outer surface of a bearing by an eddy current measuring device in order to determine the deterioration of the bearing, and in the remaining life diagnostic method described in Patent Document 3, white light is irradiated from the outer surface of a wiring.

[0008] Therefore, it may not be possible to determine the thermal deterioration of members such as coating materials such as enamel that coat the windings of a motor and adhesive materials such as varnish that bond the windings to the core around which the windings are wound, which are not necessarily correlated with the parameters measurable from the outer surface of the motor.

[0009] The present invention has been made paying attention to the above technical problems, and an object thereof is to provide a remaining life determination system for a motor that can determine the remaining life due to thermal deterioration of members that coat the windings of the motor and members that bond the windings to the core.

Means for Solving the Problem

[0010] In order to achieve the above object, the present invention provides a remaining life determination system for a motor including an annularly formed stator, a rotor disposed to face the stator, and a coil attached to a core of either the stator or the rotor, the system comprising a controller for determining deterioration of the motor, the controller including a first acquisition unit for acquiring an impedance between the coil and the core, an estimation unit for estimating a total heat input amount to the motor based on a magnitude of the impedance between the coil and the core, and a determination unit for determining a remaining life due to thermal deterioration of the motor based on the total heat input amount estimated by the estimation unit.

[0011] In the present invention, the controller further includes a first database storing a relationship between a high-temperature storage time when the motor is exposed to a predetermined first predetermined temperature and a magnitude of the impedance, and the estimation unit may estimate the total heat input amount to the motor based on the first acquisition unit Impedance obtained by and the first database.

[0012] In the present invention, the system further includes a coating material for coating the coil, the controller further includes a second database storing a relationship between the total heat input amount to the motor and a tensile strength of the coating material, and the determination unit may determine the remaining life due to the thermal deterioration of the motor based on the total heat input amount estimated by the estimation unit and the second database.

[0013] In the present invention, the system further includes a measuring instrument including a power supply for applying a predetermined voltage to the coil and the core, a sensor for detecting a current flowing through the coil and the core, and a calculation unit for obtaining an impedance between the coil and the core based on the voltage applied by the power supply and the current value detected by the sensor, and the first acquisition unit may acquire the impedance between the coil and the core from the measuring instrument.

[0014] In the present invention, the predetermined voltage includes an alternating voltage having a predetermined frequency, and the calculation unit may obtain the impedance based on the alternating voltage and the leakage current flowing between the coil and the core.

[0015] In the present invention, the controller further includes a second acquisition unit that acquires the reflectance of a predetermined part of the motor, and a third database that stores the relationship between the reflectance, the high-temperature storage time, the thermal shock times which is the number of times the temperature of the motor changes between a second predetermined temperature and a third predetermined temperature. The first database stores the relationship between the impedance, the high-temperature storage time, and the thermal shock times. The estimation unit is configured to estimate the total heat input to the motor and the thermal shock times of the motor based on the impedance acquired by the first acquisition unit, the reflectance acquired by the second acquisition unit, the first database, and the third database. The determination unit may determine the remaining life of the motor due to high-temperature stress based on the total heat input estimated by the estimation unit and the remaining life of the motor due to thermal shock based on the thermal shock times estimated by the estimation unit.

[0016] In the present invention, an adhesive material interposed between the coil and the core is further provided. The controller further includes a fourth database that stores the relationship between the thermal shock times of the motor and the shear stress of the adhesive material. The determination unit may determine the remaining life of the motor due to thermal shock based on the thermal shock times estimated by the estimation unit and the fourth database.

[0017] In the present invention, when measuring such as when obtaining impedance from detection data such as current values, or when constructing a database when determining the relationship between impedance and high-temperature storage time, data related to external factors such as measurement environment and measurement conditions is determined by artificial intelligence, so that the accuracy of the correlation of measurement values and the database may be improved.

Effect of the Invention

[0018] According to the present invention, the impedance between the core of the stator or rotor and the coil attached to the core is obtained, and the total heat input to the motor is estimated based on the obtained impedance. Then, the remaining life due to thermal degradation of the motor is determined based on the estimated total heat input. Therefore, without destroying the motor, it is possible to determine the remaining life due to thermal degradation of the motor including members covering the coil and adhesive materials intervening between the core and the coil, so that the remaining life of the motor after market driving can be determined, and the motor can be reused for rebuild and reuse, or the motor can be replaced before it fails.

Brief Description of the Drawings

[0019]

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Embodiments for Carrying Out the Invention

[0020] The present invention will be described based on the embodiments shown in the drawings. Note that the embodiments described below are merely examples when the present invention is embodied, and do not limit the present invention.

[0021] The motor in the embodiment of the present invention is a motor including a stator, a rotor, and a coil wound around a predetermined part of at least one of the stator and the rotor. It may be a brushed DC motor with a coil wound around the rotor, or an AC motor with a coil wound around the stator, or coils wound around both the stator and the rotor. Also, it may be an axial-gap type motor, not limited to a radial-gap type motor. FIG. 1 shows an example of a stator 1 used in a three-phase AC type motor provided as a driving power source for a conventional electric vehicle or hybrid vehicle, more specifically, a permanent magnet synchronous motor.

[0022] The stator 1 shown in FIG. 1 is configured by laminating steel plates 2 formed in an annular shape in the axial direction, similar to a conventional stator. Each steel plate 2 is composed of an annular yoke portion 3 and a plurality of teeth portions (not shown) protruding toward the center of the yoke portion 3. An attachment portion (not shown) protruding radially outward is formed on the outer peripheral surface of each yoke portion 3, and each yoke portion 3 is configured to be constrained in the axial direction by fixing the attachment portion to a case (not shown). By laminating and integrating a plurality of steel plates 2 in the axial direction in this way, a core 4 is formed.

[0023] The plurality of teeth portions are formed at predetermined intervals in the circumferential direction of the yoke portion 3, and a coil 5 is wound around the teeth portion. This coil 5 may be composed of a relatively thin copper wire with a circular cross-sectional shape, or may be composed of a relatively thick copper wire with a rectangular cross-sectional shape. Note that, for the sake of convenience, FIG. 1 schematically shows only the coil end portion 6 of the coil 5 protruding in the axial direction of the core 4.

[0024] The above-mentioned coil 5 is formed by the contact of copper wires. Therefore, each copper wire is coated with a coating material such as enamel to insulate it from adjacent copper wires. In addition, an adhesive material such as varnish is applied to the coil 5 to cure the copper wire or to bond the copper wire to the tooth portion. In the coil end portion 6, power lines 7u, 7v, and 7w are connected to the U-phase, V-phase, and W-phase, and terminals 8u, 8v, and 8w are attached to the ends of the power lines 7u, 7v, and 7w.

[0025] In the motor configured as described above, the coil 5 heats up due to copper loss and iron loss during driving, so the tensile strength of the enamel decreases. FIG. 2 shows the experimental results of verifying the relationship between the time (high-temperature storage time) when the enamel is exposed to a high-temperature environment of a predetermined first predetermined temperature and the tensile strength of the enamel. The horizontal axis represents the high-temperature storage time, and the vertical axis represents the tensile strength of the enamel. Five test pieces were used for verification, and the tensile strength of each test piece is plotted with "○", and the average value is shown by a line.

[0026] As shown in FIG. 2, it can be seen that the tensile strength of the enamel decreases as the high-temperature storage time increases. That is, the higher the total heat input to the enamel, the lower the tensile strength of the enamel. Therefore, when the total heat input to the motor reaches the total heat input at which the tensile strength of the enamel becomes a predetermined value, it is the life of the motor. The database mapping the relationship between the tensile strength of the enamel and the high-temperature storage time shown in FIG. 2 corresponds to the "second database" in the embodiment of the present invention, and this database is stored in the ECU 12 described later. In the following description, this database is referred to as a tensile strength map.

[0027] On the other hand, when the motor is exposed to a high-temperature environment at a predetermined temperature for a predetermined time, the volume of the varnish decreases. FIG. 3 shows the experimental results of measuring the volume change rate (reduction rate) of the varnish when the motor is stored at a high temperature for a predetermined time. Here, experiments were conducted using eight test pieces (TP). As shown in FIG. 3, it can be seen that the volume of the varnish decreases by an average of 4.22% when the motor is exposed to a high-temperature environment for a predetermined time.

[0028] The distance between the coil 5 and the core 4 and the facing area between the coil 5 and the core 4 are considered to be constant and not affected by the high-temperature storage time. On the other hand, when the volume of the varnish changes as described above, as shown in FIG. 4, a part of the varnish 9 peels off from the coil 5 and the core 4, and air intervenes in the peeled part, so that the dielectric constant between the coil 5 and the core 4 is considered to change. That is, it is considered that the impedance (more specifically, the capacitance) between the coil 5 and the core 4 changes.

[0029] Therefore, the remaining life determination system of the motor in the embodiment of the present invention is configured to estimate the total heat input to the motor based on the impedance between the coil 5 and the core 4, and determine the remaining life of the motor based on the total heat input.

[0030] FIG. 1 shows an example of the remaining life determination system 10. The remaining life determination system 10 shown here is composed of an LCR meter 11 for measuring the impedance between the coil 5 and the core 4, and an electronic control unit (hereinafter referred to as ECU) 12 for determining the remaining life of the motor from the measured value. Note that the LCR meter 11 corresponds to the "measuring device" in the embodiment of the present invention, and the ECU 12 corresponds to the "controller" in the embodiment of the present invention.

[0031] The LCR meter 11 is composed of an AC power supply 13 that applies an AC voltage to the coil 5 and the core 4, a current sensor 14 that detects the current (leakage current) flowing between the coil 5 and the core 4, and a calculation unit 15 that obtains the impedance such as the inductance, capacitance, and resistance of the object from the output voltage (applied voltage) and the current value. That is, the LCR meter 11 is connected to the coil 5 and the core 4. And, based on the AC voltage applied between the coil 5 and the core 4 and the current value detected by the current sensor 14, the calculation unit 15 is configured to obtain the inductance, capacitance, or resistance. Here, although the power lines 7u, 7v, and 7w are short-circuited to measure the current value between the coil 5 and the core 4, the current value between the power line 7u connected to the U phase and the core 4 may be measured, or the current value between the power line connected to any phase and the core 4 may be measured.

[0032] Fig. 5 shows an example of the current value detected by the current sensor 14 when an AC voltage is applied between the coil 5 and the core 4. Note that the vertical axis in Fig. 5 shows both the voltage value and the current value, and the horizontal axis shows time. As shown in Fig. 5, a predetermined phase difference θ occurs between the AC voltage of a predetermined frequency and the current (leakage current) value detected by the current sensor 14. Therefore, the calculation unit 15 calculates the capacitance Cs based on the following formula (1). Cs = Zcosθ …(1) Here, Z is the ratio (V / I) of the maximum value V of the voltage and the maximum value I of the current.

[0033] The ECU 12 is mainly composed of a microcomputer and is configured to determine the remaining life of the motor based on the input data and a database such as a map stored in advance.

[0034] The ECU 12 shown in FIG. 1 includes a first acquisition unit 16 that acquires the capacitance Cs, an estimation unit 17 that estimates the total heat input to the motor based on the capacitance Cs acquired by the first acquisition unit 16, and a determination unit 18 that determines the remaining life of the motor based on the total heat input estimated by the estimation unit 17.

[0035] The first acquisition unit 16 is configured to acquire the value of the capacitance Cs calculated by the calculation unit 15 in the LCR meter 11.

[0036] The estimation unit 17 is configured to expose the motor to a high-temperature environment, measure the capacitance Cs every predetermined time, and estimate the total heat input to the motor based on a database in which the relationship between the high-temperature storage time and the capacitance Cs is mapped. Specifically, it is configured to obtain the high-temperature storage time from the database and the capacitance Cs acquired by the first acquisition unit 16, and estimate the heat amount corresponding to the high-temperature storage time as the total heat input to the motor.

[0037] FIG. 6 shows an example of the database, with the capacitance Cs on the vertical axis and the high-temperature storage time on the horizontal axis. As shown in FIG. 6, the capacitance Cs decreases as the high-temperature storage time increases. Here, the total heat input can be calculated by integrating the storage temperature and the storage time. That is, the high-temperature storage time and the total heat input can be regarded as substantially synonymous. Note that this database corresponds to the "first database" in the embodiment of the present invention, and in the following description, it is referred to as the total heat input map.

[0038] The determination unit 18 is configured to determine the remaining life of the motor from the total heat input estimated by the estimation unit 17 and the tensile strength map. Specifically, it is configured to determine the upper limit heat amount, which is the upper limit value of the total heat input, from the tensile strength map and the allowable lower limit value of the tensile strength of the enamel, and determine the remaining life due to thermal degradation based on the total heat input estimated by the estimation unit 17 with respect to the upper limit heat amount.

[0039] FIG. 7 shows an example of a determination flow executed by the ECU 12. In the example shown in FIG. 7, first, the impedance (capacitance) is acquired from the LCR meter 11 (step S1). Next, with reference to the total heat input map, the total heat input of the motor is estimated (step S2). Subsequently, based on the total heat input estimated in step S2 and the tensile strength map, the remaining life of the motor is determined (step S3), and this routine is terminated once.

[0040] As described above, by acquiring the capacitance between the coil 5 and the core 4, the total heat input to the motor can be determined. Therefore, based on the tensile strength map showing the relationship between the total heat input to the motor and the tensile strength of the enamel, the remaining life due to thermal degradation of the motor can be determined. Therefore, without destroying the motor, it is possible to determine the remaining life due to thermal degradation of the motor including the member (enamel) covering the coil 5 and the adhesive (varnish) interposed between the core 4 and the coil 5. Thus, it is possible to determine the remaining life of the motor after market driving and reuse the motor for rebuild and reuse, or replace the motor before it fails.

[0041] In addition, in the market, the motor is thermally degraded by thermal shock caused by repeated changes in the motor temperature between high and low temperatures, in addition to the high-temperature stress caused by maintaining the temperature rise due to copper loss and iron loss of the motor.

[0042] Therefore, the remaining life determination system in the embodiment of the present invention is configured to determine the thermal degradation of the motor by separating the thermal degradation (high-temperature stress) caused by exposure to a high-temperature environment and the thermal degradation (thermal shock) associated with temperature changes. FIG. 8 is a schematic diagram for explaining the remaining life determination system, and in addition to the example shown in FIG. 1, it includes an optical spectrum analyzer 19.

[0043] This optical spectrum analyzer 19 includes a probe 20 that irradiates a predetermined part of the motor with white light and receives the reflected light, a spectroscope 21 that spectrally decomposes the reflection intensity of the reflected light received by the probe 20 for each wavelength, and a reflectance calculation unit 22 that obtains the reflectance of the reflected light. This optical spectrum analyzer 19 can be configured in the same manner as a conventional device for calculating reflectance. In the example shown in FIG. 8, it is configured to calculate the reflectance of the coil end portion 6, but it may be configured to calculate the reflectance of any surface of a member integrated with the motor.

[0044] Further, the ECU 12 shown in FIG. 8 further includes a second acquisition unit 23 that acquires the reflectance data calculated by the optical spectrum analyzer 19 in addition to the functions shown in FIG. 1. Further, the ECU 12 shown in FIG. 8 includes a database that maps the relationship between the thermal load obtained by adding the number of thermal shock cycles to the high-temperature storage time and the capacitance, and a database that maps the relationship between the high-temperature storage time, the number of thermal shock cycles, and the reflectance. The ECU 12 is configured to estimate the total heat input to the motor and the number of thermal shock cycles of the motor from those databases. Here, the number of thermal shock cycles is the number of cycles with a process of raising the temperature of the motor from a predetermined second temperature to a third temperature and then lowering the temperature from the third temperature to the second temperature as one cycle. Note that the third predetermined temperature is set lower than the first predetermined temperature described above.

[0045] FIG. 9 is an example of a capacitance map constructed by measuring in advance the relationship between the high-temperature storage time, the number of thermal shock cycles, and the capacitance through experiments. The thermal shock cycles are taken on the X-axis, the high-temperature storage time is taken on the Y-axis, and the capacitance is taken on the Z-axis. As shown in FIG. 9, the capacitance decreases as the high-temperature storage time increases, and the capacitance also decreases as the number of thermal shock cycles increases. Note that the capacitance map is a map for estimating the total heat input to the motor based on the impedance between the coil 5 and the core 4. Therefore, the capacitance map corresponds to the "first database" in the embodiment of the present invention.

[0046] Therefore, when the capacitance calculated by the calculation unit 15 is the predetermined value Cs1, the relationship between the high-temperature storage time and the number of thermal shocks is as shown by line L1 in FIG. 10. In FIG. 10, the number of thermal shocks is taken on the horizontal axis, and the high-temperature storage time is taken on the vertical axis.

[0047] FIG. 11 is an example of a reflectance map constructed by measuring in advance the relationship between the high-temperature storage time, the number of thermal shocks, and the reflectance at a predetermined wavelength through experiments. The number of thermal shocks is taken on the X-axis, the high-temperature storage time is taken on the Y-axis, and the capacitance is taken on the Z-axis. As shown in FIG. 11, the reflectance decreases as the high-temperature storage time increases, and the reflectance also decreases as the number of thermal shocks increases. Note that this reflectance map corresponds to the "third database" in the embodiment of the present invention.

[0048] Here, the amount of decrease in reflectance with respect to the high-temperature storage time is larger than the amount of decrease in capacitance with respect to the high-temperature storage time, and the amount of decrease in reflectance with respect to the number of thermal shocks is smaller than the amount of decrease in capacitance with respect to the number of thermal shocks. That is, it can be seen that the sensitivity of the reflectance with respect to the high-temperature storage time is better than the sensitivity of the capacitance with respect to the high-temperature storage time, and conversely, the sensitivity of the capacitance with respect to the high-temperature storage time is better than the sensitivity of the reflectance with respect to the high-temperature storage time.

[0049] Therefore, when the reflectance calculated by the reflectance calculation unit 22 is the predetermined value R1, the relationship between the high-temperature storage time and the number of thermal shocks is as shown by line L2 in FIG. 12. In FIG. 12, the number of thermal shocks is taken on the horizontal axis, and the high-temperature storage time is taken on the vertical axis.

[0050] As shown in FIGS. 10 and 12, by calculating the capacitance and the reflectance, the relationship between the high-temperature storage time and the number of thermal shocks can be extracted. Therefore, as shown in FIG. 13, the estimation unit 17 can estimate the high-temperature storage time and the number of thermal shocks by extracting the intersection of line L1 and line L2.

[0051] And, similar to the above-described example, the determination unit 18 is configured to determine the remaining life of the motor from the total heat input estimated by the estimation unit 17 and the tensile strength map. Specifically, the upper limit heat amount, which is the upper limit value of the total heat input, is determined from the tensile strength map and the allowable lower limit value of the tensile strength of the enamel, and based on the total heat input estimated by the estimation unit 17 with respect to the upper limit heat amount, the remaining life due to thermal degradation, more specifically, the remaining life due to high-temperature stress is determined.

[0052] Furthermore, as shown in the shear stress map in FIG. 14, as the number of thermal shocks increases, the adhesion strength (shear stress) of the varnish decreases. Therefore, by storing the shear stress map in the ECU 12 in advance and estimating the number of thermal shocks by the estimation unit 17, the remaining life of the motor due to thermal shock can be determined based on the estimated number of thermal shocks and the shear stress map of the varnish.

[0053] Specifically, the determination unit 18 determines the upper limit number of thermal shocks, which is the upper limit value of the number of thermal shocks, from the shear stress map and the allowable lower limit value of the shear stress of the varnish, and based on the number of thermal shocks estimated by the estimation unit 17 with respect to the upper limit number of thermal shocks, the remaining life due to thermal degradation, more specifically, the remaining life due to thermal shock is determined. Note that the shear stress map corresponds to the "fourth database" in the embodiment of the present invention.

[0054] FIG. 15 shows an example of a determination flow executed by the ECU 12. In the example shown in FIG. 15, first, the impedance (capacitance) is acquired from the LCR meter 11, and the reflectance is acquired from the optical spectrum analyzer 19 (step S11). Then, with reference to the capacitance map and the reflectance map, the total heat input amount (high-temperature storage time) and the number of thermal shock cycles of the motor are estimated (step S12). Subsequently, based on the total heat input amount estimated in step S12 and the tensile strength map, the remaining life due to high-temperature stress of the motor is determined, and based on the number of thermal shock cycles and the shear stress map, the remaining life due to thermal shock of the motor is determined (step S13), and this routine is terminated once.

[0055] As described above, by acquiring the capacitance between the coil 5 and the core 4, the total heat input amount to the motor can be determined. Therefore, based on the tensile strength map showing the relationship between the total heat input amount to the motor and the tensile strength of the enamel, the remaining life due to high-temperature stress of the motor can be determined. Also, by acquiring the reflectance, the number of thermal shock cycles of the motor can be determined, and based on the shear stress map showing the relationship between the number of thermal shock cycles of the motor and the adhesive strength (shear stress) of the varnish, the remaining life due to thermal shock of the motor can be determined. Therefore, in addition to the same effects as the above-described example, the degree of thermal degradation can be determined by distinguishing the remaining life due to high-temperature stress and the remaining life due to the number of thermal shock cycles. In other words, the degree of degradation of the varnish and enamel can be determined individually.

Description of Reference Numerals

[0056] 1 Stator 4 Core 5 Coil 6 Coil End Portion 9 Varnish 10 Remaining Life Judgment System 11 LCR Meter 12 Electronic Control Unit (ECU) 13 AC Power Supply 14 Current Sensor 15 Calculation unit 16, 23 Acquisition unit 17 Estimation unit 18 Judgment unit 19 Optical spectrum analyzer 20 Probe 21 Spectrometer 22 Reflectance calculation unit

Claims

1. A remaining life determination system for a motor, comprising a stator formed in a ring shape, a rotor disposed opposite to the stator, and a coil attached to a core of either the stator or the rotor, comprising a controller for determining deterioration of the motor, wherein the controller comprises a first acquisition unit that acquires an impedance between the coil and the core, an estimation unit that estimates a total heat input to the motor based on a magnitude of the impedance between the coil and the core, and a determination unit that determines a remaining life due to thermal deterioration of the motor based on the total heat input estimated by the estimation unit. A remaining life determination system for a motor, characterized by the above.

2. The remaining life determination system for a motor according to Claim 1, wherein the controller further comprises a first database storing a relationship between a high-temperature storage time during which the motor is exposed to a predetermined first predetermined temperature and a magnitude of the impedance, and the estimation unit estimates the total heat input to the motor based on the impedance acquired by the first acquisition unit and the first database. A remaining life determination system for a motor, characterized by the above.

3. The remaining life determination system for a motor according to Claim 1, further comprising a coating material that coats the coil, wherein the controller further comprises a second database storing a relationship between the total heat input to the motor and a tensile strength of the coating material, and the determination unit determines the remaining life due to the thermal deterioration of the motor based on the total heat input estimated by the estimation unit and the second database. A remaining life determination system for a motor, characterized by the above.

4. The remaining life determination system for a motor according to Claim 1, further comprising a measuring instrument constituted by a power supply that applies a predetermined voltage to the coil and the core, a sensor that detects a current flowing through the coil and the core, and a calculation unit that obtains an impedance between the coil and the core based on the voltage applied by the power supply and the current value detected by the sensor, wherein the first acquisition unit acquires the impedance between the coil and the core from the measuring instrument. A remaining life determination system for a motor, characterized by the above.

5. The remaining life determination system for a motor according to Claim 4, wherein the predetermined voltage includes an alternating voltage having a predetermined frequency. The calculation unit obtains the impedance based on the AC voltage and the leakage current flowing between the coil and the core. A remaining life determination system for a motor, characterized in that.

6. The remaining life determination system for a motor according to claim 2, wherein The controller A second acquisition unit that acquires the reflectance of a predetermined part of the motor in advance; The reflectance, the high-temperature storage time, and a third database storing the relationship between the thermal shock times, which is the number of times the temperature of the motor changes between a predetermined second temperature and a predetermined third temperature; The first database stores the relationship between the impedance, the high-temperature storage time, and the thermal shock times. The estimation unit is configured to estimate the total heat input to the motor and estimate the thermal shock times of the motor based on the impedance acquired by the first acquisition unit, the reflectance acquired by the second acquisition unit, the first database, and the third database. The determination unit determines the remaining life of the motor due to high-temperature stress based on the total heat input estimated by the estimation unit and the remaining life of the motor due to thermal shock based on the thermal shock times estimated by the estimation unit. A remaining life determination system for a motor, characterized in that.

7. The remaining life determination system for a motor according to claim 6, wherein An adhesive interposed between the coil and the core is further provided. The controller further includes a fourth database storing the relationship between the thermal shock times of the motor and the shear stress of the adhesive. The determination unit determines the remaining life of the motor due to thermal shock based on the thermal shock times estimated by the estimation unit and the fourth database. A remaining life determination system for a motor, characterized in that.

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