Deterioration determination device and deterioration determination method

Abstract

A deterioration discriminating device (21) comprises a temperature acquiring unit (22), a damage amount determination unit (23), and a discrimination unit (24). The temperature acquiring unit (22) acquires the temperature of an insulating member covering a conductor. The damage amount determination unit (23) determines, for each target period, from the temperature of the insulating member and a relationship between the temperature of the insulating member and a usable life indicating a period during which the insulating member can be used, a damage amount indicating an elapsed time within the usable life corresponding to the temperature of the insulating member. The discrimination unit (24) discriminates the degree of the deterioration of the insulating member on the basis of the damage amount determined for each target period.

Description

[Technical field]

[0001] The present disclosure relates to a deterioration determination device and a deterioration determination method. [Background technology]

[0002] The electric motor includes a rotor having a rotor core and rotor conductors or permanent magnets inserted into slots formed in the rotor core, and a stator having a stator core and stator coils inserted into slots formed in the stator core. The electric motor further includes an insulating member that insulates the stator core from the stator coil. Deterioration of the insulating member may cause a short circuit inside the electric motor, a ground fault to the outside of the electric motor, or the like, so it is preferable to periodically check the degree of deterioration of the insulating member.

[0003] The electric motors mounted on railroad vehicles are large and attached to a bogie that supports the car body, and therefore maintenance work including removing the electric motor from the bogie, disassembling the electric motor, etc. is complicated. For this reason, it is difficult to frequently remove the electric motor from the bogie and remove the insulating members from the electric motor to check the degree of deterioration of the insulating members. Therefore, it is preferable to determine the degree of deterioration of the insulating members without removing the electric motor from the bogie and disassembling the electric motor. An example of a device for determining the degree of deterioration of insulating members is disclosed in Patent Document 1. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2014-25753 A Summary of the Invention [Problem to be solved by the invention]

[0005] The degradation diagnosis device disclosed in Patent Document 1 measures the coil temperature of a motor and converts the usage time of the motor at the measured actual temperature into the usage time of the motor at a reference temperature. In detail, the usage time of the motor at the actual temperature is converted into the usage time of the motor at the reference temperature by assuming that the slope of the Arrhenius plot at the actual temperature is the same as the slope of the Arrhenius plot at the reference temperature. The degradation diagnosis device diagnoses the presence or absence of insulation degradation of the coil by comparing the integrated value of the converted usage time with the coil's lifespan at the reference temperature.

[0006] When the activation energy in the Arrhenius equation, which shows the relationship between the temperature and the service life of an insulating material, changes depending on the temperature, the slope of the Arrhenius plot differs depending on the temperature. When the slope of the Arrhenius plot changes depending on the temperature, the error when converting the usage time also increases, so the accuracy of the deterioration diagnosis of the deterioration diagnosis device disclosed in Patent Document 1 decreases. This problem is not limited to the insulating material provided in the electric motor, but occurs when determining the degree of deterioration of the insulating material that covers various conductors.

[0007] The present disclosure has been made in consideration of the above circumstances, and has an object to provide a deterioration determination device and a deterioration determination method that can accurately determine the degree of deterioration of an insulating member covering a conductor. [Means for solving the problem]

[0008] In order to achieve the above object, the deterioration determination device of the present disclosure includes a temperature acquisition unit, a damage degree determination unit, and a determination unit. The temperature acquisition unit acquires a temperature of an insulating member covering a conductor. The damage degree determination unit determines the temperature of the insulating member acquired by the temperature acquisition unit for each target period. The temperature of the insulating material after the correction is increased. From the relationship between the temperature of the insulating member and the service life indicating the period during which the insulating member can be used, Corrected The damage degree indicating the time elapsed within the service life corresponding to the temperature of the insulating member is determined. Once Based on this, the degree of deterioration of the insulating member is determined. Effect of the Invention

[0009] The deterioration determination device of the present disclosure determines the degree of deterioration of an insulating member based on the degree of damage, which indicates the amount of time that has elapsed within the service life corresponding to the temperature of the insulating member, and therefore makes it possible to accurately determine the degree of deterioration of the insulating member. [Brief description of the drawings]

[0010] [Figure 1] Block diagram of a deterioration determination device according to a first embodiment. [Diagram 2] FIG. 1 is a diagram showing a hardware configuration of a deterioration determination device according to a first embodiment. [Diagram 3] 1 is a flowchart showing an example of an operation of a deterioration degree determination process performed by the deterioration determination device according to the first embodiment. [Figure 4] FIG. 1 is a diagram showing an example of a relationship between temperature and service life of an insulating member according to the first embodiment. [Diagram 5] Block diagram of a deterioration determination device according to a second embodiment. [Figure 6] 11 is a flowchart showing an example of an operation of a deterioration degree determination process performed by a deterioration determination device according to a second embodiment. [Figure 7] FIG. 1 is a block diagram of a first modified example of a deterioration determination device according to an embodiment. [Figure 8] 10 is a flowchart showing another example of the operation of the deterioration degree determination process performed by the deterioration determination device according to the embodiment. [Figure 9] FIG. 11 is a block diagram of a second modified example of the deterioration determination device according to the embodiment. [Figure 10] FIG. 13 is a diagram showing a modification of the hardware configuration of the deterioration determination device according to the embodiment; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A deterioration determination device and a deterioration determination method according to embodiments of the present disclosure will be described in detail below with reference to the drawings, in which the same or equivalent parts are designated by the same reference numerals.

[0012] (Embodiment 1) An example of a device having an insulating member covering a conductor is an electric motor that is mounted on a railway vehicle and receives a supply of electric power to drive the railway vehicle to generate a propulsive force. A deterioration determination device that determines the degree of deterioration of an insulating member of an electric motor will be described in the first embodiment. Determining the degree of deterioration of an insulating member includes determining whether the insulating member has reached its lifespan and determining whether the insulating member is approaching the end of its lifespan.

[0013] As shown in FIG. 1, a motor 91 that is the subject of deterioration determination is, for example, a three-phase induction motor that is driven by a supply of three-phase AC power from a power conversion device 11 to generate propulsive force for a railway vehicle.

[0014] Although the details of the configuration of the electric motor 91 are not shown, the electric motor 91 includes a rotatably supported shaft, a rotor having a rotor core and a rotor conductor or permanent magnets inserted into slots formed on the outer peripheral surface of the rotor core, and a stator having a stator core and a stator coil inserted into slots formed on the inner peripheral surface of the stator core. The electric motor 91 further includes an insulating member that covers the stator coil, which is a conductor. By providing the insulating member, the stator core and the stator coil are insulated, and adjacent stator coils are insulated from each other. The stator coil is covered with the insulating member by impregnating the stator with insulating varnish, which is an example of an insulating member.

[0015] The electric motor 91 is attached to a bogie that supports the body of the railcar. When the electric motor 91 receives power from the power conversion device 11 and operates, the shaft of the electric motor 91 rotates, and the rotational force of the shaft is transmitted to the axle via a joint and a gear device. Then, as the axle rotates, the wheels attached to both ends of the axle rotate, providing propulsive force for the railcar.

[0016] The power conversion device 11 that supplies power to the motor 91 is, for example, a DC-three-phase conversion device that is mounted on a railway vehicle that uses a DC power supply system and converts DC power supplied from a power source into three-phase AC power and supplies the power to a load device. The power conversion device 11 includes an input terminal 11a that is connected to a power source and an input terminal 11b that is grounded. The power conversion device 11 further includes a power conversion circuit 12 that converts DC power supplied from the power source into three-phase AC power and supplies the three-phase AC power to the motor 91, a power conversion circuit control unit 13 that controls the power conversion circuit 12, a voltage detection circuit 14 that measures a phase voltage output by the power conversion circuit 12, and a current detection circuit 15 that measures a phase current output by the power conversion circuit 12. The power conversion device 11 further includes a reactor L1 and a capacitor C1 that are connected in series between the input terminals 11a and 11b. The power conversion device 11 having the above configuration is attached under the floor of a car body of a railway vehicle.

[0017] The input terminal 11a is electrically connected to a power source, specifically, a current collector that acquires power supplied from a substation through a power supply line, via a contactor, a circuit breaker, etc. (not shown). For example, the current collector is a pantograph that acquires power through an overhead line, which is an example of a power supply line, or a current collector shoe that acquires power through a third rail, which is an example of a power supply line. The input terminal 11b is grounded via a ground ring, a ground brush, a wheel, etc. (not shown).

[0018] The power conversion circuit 12 is formed, for example, by an inverter in which the effective voltage and frequency of the output AC power are variable. The power conversion circuit 12 has a plurality of switching elements, and the switching operation of each switching element is controlled by a power conversion circuit control unit 13. Each switching element is formed, for example, by a switching element using an IGBT (Insulated Gate Bipolar Transistor) or a wide band gap semiconductor formed of SiC (Silicon Carbide), GaN (Gallium Nitride), diamond, or the like.

[0019] The power conversion circuit control unit 13 obtains an operation command S1 from a driver's cab (not shown). The operation command S1 indicates a command corresponding to an operation by a driver to a master controller provided in the cab. Specifically, the operation command S1 indicates any one of a powering command for instructing acceleration of the railcar, a braking command for instructing deceleration of the railcar, and a coasting command for instructing the railcar to run by inertia. The coasting command means a state in which neither a powering command nor a braking command is input. The power conversion circuit control unit 13 generates and outputs a power conversion control signal S2 for controlling each switching element of the power conversion circuit 12 in response to the operation command S1. The power conversion control signal S2 is, for example, a PWM (Pulse Width Modulation) signal.

[0020] The voltage detection circuit 14 has a VT (Voltage Transformer) electrically connected to a bus bar that electrically connects the power conversion circuit 12 and the electric motor 91, and measures the phase voltages output by the power conversion circuit 12, specifically, the U-phase voltage, the V-phase voltage, and the W-phase voltage. The voltage detection circuit 14 sends the measurement values ​​of each phase voltage to the deterioration determination device 21.

[0021] The current detection circuit 15 has an electric circuit between the power conversion circuit 12 and the motor 91, for example a CT (Current Transformer) attached to a bus bar electrically connecting the power conversion circuit 12 and the motor 91, and measures the values ​​of the phase currents output by the power conversion circuit 12, specifically, the U-phase current, the V-phase current, and the W-phase current. The current detection circuit 15 sends the measured values ​​of the phase currents to the power conversion circuit control unit 13 and the deterioration determination device 21.

[0022] One end of the reactor L1 is connected to the input terminal 11a. The other end of the reactor L1 is connected to a primary terminal of the power conversion circuit 12. One end of the capacitor C1 is connected to a connection point between the other end of the reactor L1 and the primary terminal of the power conversion circuit 12. The other end of the capacitor C1 is connected to a connection point between the input terminal 11b and the primary terminal of the power conversion circuit 12. The reactor L1 and the capacitor C1 form an LC filter that attenuates harmonic components generated by the switching operation of the power conversion circuit 12.

[0023] The deterioration determination device 21 that determines the degree of deterioration of the insulating member of the above-mentioned electric motor 91 includes a temperature acquisition unit 22 that acquires the temperature of the insulating member covering the stator coil of the electric motor 91, a damage degree determination unit 23 that determines the damage degree that is an index showing the time that has elapsed within the service life of the insulating member according to the temperature, and a determination unit 24 that determines the degree of deterioration of the insulating member based on the damage degree. The deterioration determination device 21 is provided at an arbitrary position in the railway vehicle, for example, under the floor of the car body.

[0024] The deterioration determination device 21 having the above configuration performs a process of determining the degree of deterioration of an insulating member for each arbitrarily determined target period, and sends the determination result on the degree of deterioration of the insulating member to the output destination device 31. The target period is a time that is sufficiently shorter than the thermal time constant of the conductor covered by the insulating member that is the target of determination by the deterioration determination device 21, and is, for example, a time that is longer than or equal to 1 second and shorter than or equal to 5 seconds. In detail, the deterioration determination device 21 determines the degree of deterioration of the insulating member for each target period from the start of use of the conductor. The output destination device 31 is, for example, a display device provided in the driver's cab.

[0025] The temperature acquisition unit 22 estimates the resistance value of the conductor from the current flowing through the conductor and the potential of the conductor, estimates the temperature of the conductor from the estimated resistance value, and uses the estimated temperature of the conductor as the temperature of the insulating member. In the first embodiment, the temperature acquisition unit 22 calculates the coil resistance value of the stator coil, which is a conductor, from the measured values ​​of the phase voltages acquired from the voltage detection circuit 14 and the measured values ​​of the phase currents acquired from the current detection circuit 15. Since the coil resistance value and the temperature of the stator coil are positively correlated, the temperature acquisition unit 22 estimates the temperature of the stator coil from the calculated coil resistance value.

[0026] When current is applied, the stator coil generates heat, and heat is transferred to the insulating material covering the stator coil, and the insulating material is heated until it reaches the same temperature as the stator coil. Therefore, it can be considered that the temperature of the stator coil and the temperature of the insulating material are the same. The temperature acquisition unit 22 outputs the estimated stator coil temperature to the damage degree determination unit 23 as the temperature of the insulating material.

[0027] The damage degree determination unit 23 determines, for each target period, a damage degree indicating the time that has elapsed within the useful life corresponding to the temperature of the insulating member, from the temperature of the insulating member acquired from the temperature acquisition unit 22 and the relationship between the temperature of the insulating member and the useful life. The useful life is the period during which the insulating member can be used, and varies according to the temperature of the insulating member. In detail, the relationship between the temperature of the insulating member and the useful life indicates that the useful life becomes shorter as the temperature increases. The relationship between the useful life LT and the temperature T (unit: K) of the insulating member is expressed by the Arrhenius equation shown in the following formula (1). In the following formula (1), A is a frequency factor, Ea is activation energy, and R is a gas constant.

[0028]

number

[0029] In the first embodiment, the damage degree determiner 23 determines the damage degree, which is the ratio of the target period to the useful life LT according to the temperature of the insulating member. In detail, the damage degree determiner 23 uses the value τ / LT obtained by dividing the target period τ by the useful life LT as the damage degree. The damage degree determiner 23 outputs the value τ / LT obtained by dividing the target period τ by the useful life LT to the discriminator 24 as the damage degree.

[0030] The discrimination unit 24 discriminates the degree of deterioration of the insulating member based on the damage degree determined for each target period τ from the start of use of the conductor. In detail, the discrimination unit 24 discriminates the degree of deterioration of the insulating member based on the damage degree determined for each target period τ in a discrimination period that starts from the start of use of the conductor and includes a plurality of target periods τ. In the first embodiment, the discrimination unit 24 discriminates the degree of deterioration of the insulating member based on the accumulated damage degree, which is the accumulated value of the damage degree in the discrimination period. For example, the discrimination unit 24 calculates the accumulated damage degree in the discrimination period and discriminates whether the accumulated damage degree has reached a threshold value. When the accumulated damage degree in the discrimination period reaches the threshold value, it can be considered that the insulating member has reached its lifespan. According to Miner's rule, when the accumulated damage degree of a member reaches 1, it can be considered that the member has reached its lifespan. Therefore, the discrimination unit 24 sets the threshold value to 1 and discriminates whether the accumulated damage degree in the discrimination period has reached the threshold value. The discrimination unit 24 stores the accumulated damage degree in a storage device (not shown) and sends the discrimination result to the output destination device 31.

[0031] The discrimination period begins at the start of use of the conductor, for example, when a railway vehicle equipped with the electric motor 91 starts operating for the first time, and continues until maintenance work is performed on the insulating members of the electric motor 91, specifically, maintenance work for re-impregnating the stator with insulating varnish. The accumulated damage degree stored in the storage device is reset when the above-mentioned maintenance work on the insulating members of the electric motor 91 is performed.

[0032] The output destination device 31 that receives the determination result from the deterioration determination device 21 having the above configuration includes, for example, a display device provided in the driver's cab. When the display device receives the determination result indicating that the insulating member has reached the end of its life from the deterioration determination device 21, the display device displays the obtained determination result on a screen.

[0033] 2 shows the hardware configuration of the deterioration determination device 21 having the above-mentioned configuration. The deterioration determination device 21 includes a processor 61, a memory 62, and an interface 63. The processor 61, the memory 62, and the interface 63 are connected to one another via a bus 60. The functions of each part of the deterioration determination device 21 are realized by software, firmware, or a combination of software and firmware. The software and firmware are written as programs and stored in the memory 62. The processor 61 reads out and executes the programs stored in the memory 62, thereby realizing the functions of each part described above. That is, the memory 62 stores programs for executing the processing of each part of the deterioration determination device 21.

[0034] The memory 62 includes, for example, non-volatile or volatile semiconductor memory such as RAM (Random Access Memory), ROM (Read-Only Memory), flash memory, EPROM (Erasable Programmable Read Only Memory), EEPROM (Electrically Erasable and Programmable Read-Only Memory), magnetic disks, flexible disks, optical disks, compact disks, mini disks, DVDs (Digital Versatile Discs), etc.

[0035] The deterioration determination device 21 is connected to the voltage detection circuit 14, the current detection circuit 15, the output destination device 31, etc. via an interface 63. The interface 63 has an interface module that complies with one or more standards depending on the connection destination.

[0036] The operation of the above-mentioned power conversion device 11 will be described below. When the operation command S1 includes a powering command, the power conversion device 11 shown in Fig. 1 converts DC power supplied from a power source into three-phase AC power, and supplies the three-phase AC power to the electric motor 91. The electric motor 91 is driven by the supply of three-phase AC power, and generates propulsive force for the railway vehicle.

[0037] In detail, when the operation command S1 includes a powering command, the power conversion circuit control unit 13 determines a torque command value τ , which is a target value of the torque of the electric motor 91, according to a target value of the acceleration of the railway vehicle indicated by the powering command and a measured value of the rotation speed of the electric motor 91 acquired from a speed sensor (not shown). * Then, the power conversion circuit control unit 13 determines the torque command value τ * The excitation current command value id * and torque current command value iq * The power conversion circuit control unit 13 converts the measured values ​​of the phase currents obtained from the current detection circuit 15 from the three-phase coordinates to the dq rotation coordinates based on the estimated position θ estimated from the measured value of the rotation speed of the motor 91, thereby determining the excitation current value id and the torque current value iq.

[0038] The power conversion circuit control unit 13 receives the excitation current value id and the excitation current command value id * The excitation voltage command value Vd * The torque current value iq and the torque current command value iq * The torque voltage command value Vq is calculated from the difference * The power conversion circuit control unit 13 determines the excitation voltage command value Vd * and the torque voltage command value Vq * is converted from the dq rotation coordinate to the three-phase coordinate based on the estimated position θ to obtain the U-phase voltage command value Vu * , V phase voltage command value Vv * , and the W-phase voltage command value Vw * Then, the power conversion circuit control unit 13 determines the U-phase voltage command value Vu * , V phase voltage command value Vv * , and the W-phase voltage command value Vw * The power conversion control signal S2 for controlling the switching operation of each switching element of the power conversion circuit 12 is generated in response to each of the above and the carrier wave, and is output.

[0039] When the power conversion control signal S2 is supplied to the gate signal of each switching element of the power conversion circuit 12, each switching element performs a switching operation. As a result, the power conversion circuit 12 converts DC power into three-phase AC power and supplies the three-phase AC power to the electric motor 91.

[0040] When the operation command S1 includes a brake command, the electric motor 91 operating as a generator supplies three-phase AC power to the power conversion device 11. The power conversion device 11 converts the three-phase AC power supplied from the electric motor 91 into DC power, and supplies the DC power to other railway vehicles traveling near the railway vehicle on which the power conversion device 11 is mounted, via a current collector and a power supply line. The three-phase AC power generated by the electric motor 91 is supplied to and consumed by the other railway vehicles, generating a regenerative braking force that decelerates the railway vehicle.

[0041] In detail, when the operation command S1 includes a brake command, the power conversion circuit control unit 13 acquires a measurement value of the terminal voltage of the capacitor C1 from a voltage sensor (not shown), and acquires a measurement value of the phase current flowing from the motor 91 to the power conversion circuit 12 from the current detection circuit 15. Then, the power conversion circuit control unit 13 determines a voltage command value indicating a target value of the output voltage of the power conversion circuit 12, according to the measurement value of the terminal voltage of the capacitor C1 and the measurement value of the phase current flowing from the motor 91 to the power conversion circuit 12.

[0042] The target value of the output voltage of the power conversion circuit 12 is, for example, a value in a voltage range higher than the overhead line voltage and included in a target voltage range indicating a voltage range in which regenerative braking can be used. Then, the power conversion circuit control unit 13 generates and outputs a power conversion control signal S2 that controls the switching operation of each switching element of the power conversion circuit 12 according to the voltage command value.

[0043] When the power conversion control signal S2 is supplied to the gate signal of each switching element of the power conversion circuit 12, each switching element performs a switching operation. As a result, the power conversion circuit 12 converts the three-phase AC power supplied from the motor 91 into DC power, and charges the capacitor C1 with the DC power.

[0044] If another accelerating railway vehicle is located near the railway vehicle on which the power conversion device 11 is installed, as described above, the power generated by the electric motor 91 is supplied to and consumed by the other railway vehicle, generating a regenerative braking force that decelerates the railway vehicle.

[0045] Independently from the processing of the power conversion device 11 described above, the deterioration determination device 21 performs processing to determine the degree of deterioration of the insulating members of the electric motor 91. When a railway vehicle equipped with the electric motor 91 starts operation for the first time, the deterioration determination device 21 starts the processing to determine the degree of deterioration shown in Fig. 3. For example, when a pantograph up switch provided in the driver's cab of the railway vehicle equipped with the electric motor 91 is operated and the railway vehicle starts operation for the first time, the deterioration determination device 21 starts the processing to determine the degree of deterioration shown in Fig. 3. Thereafter, the deterioration determination device 21 continues to repeat the processing to determine the degree of deterioration shown in Fig. 3 for each target period τ=TP1 while the railway vehicle is in operation.

[0046] The temperature acquisition unit 22 calculates the coil resistance value of the electric motor 91 from the measured values ​​of the phase voltages acquired from the voltage detection circuit 14 and the measured values ​​of the phase currents acquired from the current detection circuit 15 (step S11). For example, in a state in which a weak current flows only through the stator coil, the temperature acquisition unit 22 calculates the line voltage between the U phase and the V phase from the measured values ​​of the U phase voltage and the V phase voltage acquired from the voltage detection circuit 14. The temperature acquisition unit 22 calculates the line voltage V uv and the measured value I of the U-phase current obtained from the current detection circuit 15. u Based on this, the coil resistance value Re of the U-phase stator coil is calculated using the following formula (2). The temperature acquisition unit 22 stores the calculated coil resistance value in a storage device not shown in FIG.

[0047]

number

[0048] In order to calculate the coil resistance value using the above formula (2), it is preferable to provide a current supply device that supplies a weak current only to the stator coil. Since the current supply device supplies a weak current only to the stator coil to calculate the coil resistance value, it is possible to calculate the coil resistance value even during coasting when power is not supplied from the power conversion device 11 to the electric motor 91.

[0049] 3, the temperature acquisition unit 22 estimates the temperature of the insulating member of the electric motor 91 from the coil resistance value calculated in step S11 (step S12). Details of step S12 will be described below.

[0050] The temperature acquisition unit 22 estimates the temperature of the stator coil, which is a conductor, from the coil resistance value calculated in step S11 and the coil resistance value calculated in the immediately preceding target period τ. The temperature acquisition unit 22 stores the estimated stator coil temperature in a storage device not shown in Fig. 1. In the first embodiment, it is assumed that the temperatures of the U-phase stator coil, the V-phase stator coil, and the W-phase stator coil included in the same electric motor 91 change in the same manner, and the temperature of the U-phase stator coil estimated based on the coil resistance value of the U-phase stator coil calculated in step S11 is used as the temperature of the stator coil of the electric motor 91.

[0051] For example, the i-th period of interest τ i Temperature T' of the stator coil at i is calculated using the following formula (3). In the following formula (3), Re i is the i-th period of interest τ i Coil resistance at, Re i-1 is the i-1th target period τ i-1 where β is the inverse of the temperature coefficient of resistance, T' i-1 is the i-1th target period τ i-1is the temperature of the stator coil at i, where i is any natural number. In the first target period τ1 where i=1, the temperature T0 of the stator coil may be set to room temperature, for example, 20° C., and Re0 may be set to the coil resistance value at room temperature. The temperature acquisition unit 22 holds information on the temperature T'0 and the coil resistance value R0 of the stator coil in advance. The inverse β of the temperature resistance coefficient is determined by the material that forms the conductor. For example, if the stator coil is made of copper, a value of 235 is used as the value of β.

[0052]

number

[0053] Heat is transferred from the stator coil to the insulating member, and the insulating member is heated until it reaches a temperature similar to that of the stator coil. Therefore, it can be considered that the temperature of the stator coil and the temperature of the insulating member covering the stator coil are the same. The temperature acquisition unit 22 acquires the temperature T' of the stator coil estimated as described above. i is the temperature T of the insulating material i and outputs the result to the damage level determining unit 23.

[0054] 3, the damage level determination unit 23 determines a damage level, which is a ratio of the target period τ to the useful life LT according to the temperature of the insulating member, in accordance with the temperature of the insulating member estimated by the temperature acquisition unit 22 in step S12 (step S13). The details of step S13 will be described below.

[0055] The damage level determination unit 23 determines the useful life LT of the insulating member according to the temperature of the insulating member estimated by the temperature acquisition unit 22. As described above, the relationship between the temperature T of the insulating member and the useful life LT is such that the higher the temperature, the shorter the useful life LT, according to the Arrhenius equation (1) above. For example, as shown in FIG. 4, the reciprocal 1 / T of the temperature of the insulating member and the logarithmic display logLT of the useful life LT of the insulating member show a positive correlation. The horizontal axis of FIG. 4 is the reciprocal 1 / T (unit: 1 / K) of the temperature of the insulating member, and the vertical axis of FIG. 4 is the logarithmic display logLT of the useful life LT. In the example of FIG. 4, the reciprocal 1 / T of the temperature of the insulating member and the logarithmic display logLT of the useful life LT have a linear relationship. For example, the damage level determination unit 23 determines the i-th target period τ based on the graph shown in FIG. 4. i Temperature T of the insulating material i The service life of the insulating material according to i Determine.

[0056] After determining the useful life LT according to the temperature of the insulating member as described above, the damage degree determination unit 23 determines the damage degree, which is the ratio of the target period τ to the useful life LT according to the temperature of the insulating member. In detail, the damage degree determination unit 23 determines the damage degree, which is the ratio of the target period τ to the useful life LT according to the temperature of the insulating member, by using the following formula (4): i Damage level D i In the following formula (4), τ i is the i-th period of interest τ i In the first embodiment, τ i is a fixed value TP1. i Damage level D i is the i-th period of interest τ i The i-th target period τ i The damage degree determining unit 23 calculates the damage degree D i is output to the discrimination unit 24.

[0057]

number

[0058] The discrimination unit 24 calculates the damage degree D calculated in step S13 for each target period τ. i Based on this, the presence or absence of deterioration of the insulating member is determined. In detail, the determination unit 24 calculates the cumulative damage degree as shown in FIG. 3 (step S14). i Accumulative damage up to ACC i is expressed by the following formula (5). In the first embodiment, in the following formula (5), τ1=τ2=τ3=...=τ i =TP1.

[0059]

number

[0060] The discrimination unit 24 determines the cumulative damage degree ACC i It is determined whether the cumulative damage degree ACC reaches a threshold value (step S15). i When the threshold value is reached (step S15; Yes), it can be determined that the insulating member has reached the end of its life, and the determination unit 24 outputs a determination result indicating that the insulating member has reached the end of its life to the output destination device 31 (step S16). When the process of step S16 is completed, the deterioration determination device 21 repeats the above-mentioned process from step S11.

[0061] Cumulative damage level ACC i If the threshold value has not been reached (step S15; No), the insulating member can be deemed not to have reached the end of its life, and therefore the deterioration determination device 21 does not perform the process of step S16, and repeats the above-described process from step S11.

[0062] Cumulative damage level ACC i has reached 1, in other words, the sum of the ratios of the target period τ to the useful life LT of the insulating material has reached 1, which means that the useful life LT of the insulating material has elapsed. Therefore, if the threshold value is set to 1, the cumulative damage degree ACC i When the threshold value is reached, the insulating member can be considered to have reached the end of its life.

[0063] For example, the first period τ1 to the i-th period τ i If the temperature is constant Te1 until the temperature reaches the specified value, the service life LT corresponding to the temperature Te1 is LTE1 as shown in Figure 4, so LT1 = LT2 = LT3 = = LT i =LTe1. Therefore, the cumulative damage level ACC i is expressed as i·TP1 / LTe1. In other words, from the first target period τ1 to the i-th target period τ i The ratio of the length to the cumulative damage level ACC i The cumulative damage level ACC is expressed as i·TP1 / LTe1. i When the threshold value is reached, the insulating member can be considered to have reached the end of its life.

[0064] The first period τ1 to the i-th period τ i Accumulative damage degree ACC when temperature changes up to i For example, when i=100, the first target period τ1 to the 50th target period τ 50 The temperature of the insulating material is Te1 during the 51st target period τ 51 In the subsequent target period τ, the temperature of the insulating material is assumed to be Te2. In this case, as shown in FIG. 4, the service life LT corresponding to temperatures Te1 and Te2, respectively, is LTE1 and LTE2, so LT1=LT2=LT3=···=LT 50 =LTe1, and LT 51 =LT 52 =···=LT 100 =LTe2. Therefore, the cumulative damage level ACC 100 is expressed as 50·TP1 / LTe1+50·TP1 / LTe2. Even if the temperature of the insulating material changes as described above, the damage level D, which indicates the time that has elapsed within the service life LT of the insulating material according to the temperature, i By using this, it is possible to accurately determine the degree of deterioration of the insulating member.

[0065] By setting the threshold value to a value smaller than 1, for example 0.8, the cumulative damage level ACC ireaches the threshold value, it can be determined that the insulating member is approaching the end of its life. In this case, the determination unit 24 outputs a determination result indicating that the insulating member is approaching the end of its life to the output destination device 31.

[0066] When the output destination device 31 obtains from the deterioration determination device 21 a determination result indicating that the insulating material has reached the end of its life or is approaching the end of its life and displays the determination result on the screen, it is preferable that maintenance work is performed, specifically, maintenance work to re-impregnate the stator of the motor 91 with insulating varnish.

[0067] As described above, the deterioration determination device 21 according to the first embodiment determines the degree of deterioration of an insulating member based on the damage degree indicating the time elapsed within the service life LT corresponding to the temperature of the insulating member, specifically, the damage degree which is determined for each service life τ and is the ratio of the service life LT corresponding to the temperature of the insulating member to the service life LT of the insulating member. Therefore, it becomes possible to determine the degree of deterioration of the insulating member covering the conductor with higher accuracy than a deterioration determination device which converts the usage time at the actual temperature into the usage time at the reference temperature and determines the presence or absence of deterioration of the insulating member based on a comparison between the integrated value of the converted usage time and the life at the reference temperature.

[0068] (Embodiment 2) The deterioration determination process in the deterioration determination device 21 is not limited to the above example. The deterioration determination device 21, which determines the degree of deterioration of an insulating member by a process different from that in the first embodiment, will be described in the second embodiment, focusing on the differences from the first embodiment.

[0069] 5 is similar to the configuration of the deterioration determination device 21 according to the first embodiment. However, unlike the deterioration determination device 21 according to the first embodiment, the deterioration determination device 21 according to the second embodiment receives a driving command S1 from the driver's cab and receives a U-phase voltage command value Vu from the power conversion circuit control unit 13. * , V phase voltage command value Vv * , and the W-phase voltage command value Vw * and obtains the measured value of each phase current from the current detection circuit 15.

[0070] The temperature acquisition unit 22 acquires the U-phase voltage command value Vu * , V phase voltage command value Vv * , and the W-phase voltage command value Vw * and calculates the resistance value of the stator coil, which is a conductor, from the measured values ​​of the currents of each phase acquired from current detection circuit 15. Temperature acquisition unit 22 estimates the temperature of the stator coil from the calculated coil resistance value. As in the first embodiment, the temperature of the stator coil and the temperature of the insulating material covering the stator coil can be considered to be the same, so temperature acquisition unit 22 outputs the estimated temperature of the stator coil as the temperature of the insulating material.

[0071] Depending on the position of the stator coil, for example, the surface area exposed to air varies, and this can cause variations in the temperature of the stator coil. In particular, there are positions in the stator coil where the temperature is higher than the temperature of the stator coil estimated from the coil resistance value. As a result, there are positions in the insulating member covering the stator coil where the temperature is higher than the temperature of the insulating member output by the temperature acquisition unit 22. Therefore, the damage level determination unit 23 included in the deterioration determination device 21 according to the second embodiment performs a correction to increase the temperature of the insulating member acquired from the temperature acquisition unit 22.

[0072] For example, the damage degree determining unit 23 multiplies the temperature of the insulating member acquired from the temperature acquiring unit 22 by a coefficient h1 that is a coefficient greater than 1. The coefficient h1 is, for example, a value that corresponds to the maximum value of the temperature of the stator coil when the average value of the temperature of the stator coil is set to 1, based on data on the temperature distribution of the stator coil.

[0073] The damage degree determining unit 23 determines the damage degree indicating the time that has elapsed within the useful life LT corresponding to the temperature of the insulating member for each target period τ, based on the temperature of the insulating member corrected as described above and the relationship between the temperature of the insulating member and the useful life LT. As a result, it becomes possible to determine the damage degree indicating the time that has elapsed within the useful life LT as the target period τ elapses, in accordance with the hot spot, which is the position where the temperature of the stator coil becomes high.

[0074] The damage degree determination unit 23 determines the damage degree from the corrected temperature of the insulating member and the relationship between the temperature of the insulating member and the useful life LT for each target period τ whose length changes according to the operation command S1. For example, the damage degree determination unit 23 sets the target period τ=TP2 during powering or braking, in other words, when the operation command S1 includes a powering command or a braking command, to be shorter than the target period τ=TP3 during coasting, in other words, when the operation command S1 includes a coasting command. This allows the damage degree determination unit 23 to determine the useful life LT corresponding to the temperature of the insulating member with high frequency during acceleration or deceleration when the temperature of the stator coil of the electric motor 91 may change suddenly, and to determine the damage degree indicating the time that has elapsed in the useful life LT. As a result, it becomes possible to accurately determine the damage degree indicating the time that has elapsed in the useful life LT by the passage of the target period τ.

[0075] The hardware configuration of the deterioration determination device 21 is similar to that of the deterioration determination device 21 according to embodiment 1. However, unlike embodiment 1, the deterioration determination device 21 is connected via an interface 63 to the current detection circuit 15, the power conversion circuit control unit 13, the output destination device 31, and in-vehicle devices including a master controller installed in the cab.

[0076] The process of determining the degree of deterioration performed by the deterioration determination device 21 having the above configuration will be described below. When a railway vehicle equipped with the electric motor 91 starts operation for the first time, the deterioration determination device 21 starts the process of determining the degree of deterioration shown in Fig. 6. The processes in steps S11 and S12 are similar to the processes performed by the deterioration determination device 21 shown in Fig. 3.

[0077] The damage level determination unit 23 performs a correction to increase the temperature of the insulating member estimated in step S12 (step S21). Then, the damage level determination unit 23 determines a damage level, which is a ratio of the target period τ to the useful life period LT according to the temperature of the insulating member, according to the temperature of the insulating member corrected in step S21 (step S13). The subsequent processes from step S14 to S16 are similar to the processes performed by the deterioration determination device 21 shown in FIG.

[0078] As described above, the deterioration determination device 21 according to the second embodiment performs a correction to increase the temperature of the insulating member, and then determines the useful life LT according to the corrected temperature of the insulating member. Therefore, when there is variation in the temperature of the insulating member, it is possible to determine the degree of deterioration of the insulating member based on a part of the insulating member that is hotter than other parts and therefore has a shorter useful life LT. Furthermore, during acceleration or deceleration, when the temperature of the insulating member may change suddenly, the deterioration determination device 21 determines the useful life LT corresponding to the temperature of the insulating member more frequently than during coasting. As a result, the accuracy of determining the degree of deterioration of the insulating member is improved.

[0079] The present disclosure is not limited to the above-described embodiment. The above hardware configuration and flowchart are merely examples, and can be changed or modified as desired.

[0080] The object of determination by deterioration determination device 21 is not limited to the stator coil of motor 91, but may be any insulating material covering a conductor. As an example, deterioration determination device 21 that determines the degree of deterioration of an insulating material covering a conductor of reactor L1 is shown in Fig. 7. The configuration of deterioration determination device 21 is similar to that of the first and second embodiments.

[0081] The power conversion device 11 includes a voltage detection circuit 16 that measures the voltage between the terminals of the reactor L1, and a current detection circuit 17 that measures the current flowing through the reactor L1.

[0082] The voltage detection circuit 16 is connected in parallel to the reactor L1 and measures the value of the terminal voltage of the reactor L1. The voltage detection circuit 16 sends the measured value of the terminal voltage to the deterioration determination device 21.

[0083] The current detection circuit 17 has a Hall element type current sensor attached to a bus bar that electrically connects the reactor L1 and the power conversion circuit 12, and measures the value of the current flowing through the reactor L1. The current detection circuit 15 sends the measured current value to the deterioration determination device 21.

[0084] The reactor L1 has a conductor and an insulating member that covers the conductor. The conductor covered with the insulating member is wound to form a disk-shaped coil.

[0085] The temperature acquisition unit 22 calculates a coil resistance value of the disk-shaped coil of the reactor L1 from the measured value of the terminal voltage of the reactor L1 acquired from the voltage detection circuit 16 and the measured value of the current flowing through the reactor L1 acquired from the current detection circuit 17. In detail, the temperature acquisition unit 22 calculates the coil resistance value by dividing the measured value of the terminal voltage of the reactor L1 by the measured value of the current flowing through the reactor L1. As in the first and second embodiments, the temperature acquisition unit 22 estimates the temperature of the conductor of the disk-shaped coil from the calculated coil resistance value.

[0086] When current is applied, heat is transferred from the conductor of the disk-shaped coil, which generates heat, to the insulating material that covers the conductor, and the insulating material is heated until it reaches the same temperature as the conductor. Therefore, the temperature of the conductor and the insulating material of the disk-shaped coil can be considered to be the same. Therefore, the temperature acquisition unit 22 outputs the estimated temperature of the disk-shaped coil to the damage degree determination unit 23 as the temperature of the insulating material.

[0087] Damage level determining unit 23 and determining unit 24 perform the same processes as those in the first and second embodiments, so that it becomes possible to determine the degree of deterioration of the insulating member of reactor L1.

[0088] The method of acquiring the temperature of the insulating member by the temperature acquiring unit 22 is not limited to the above example. As an example, the temperature acquiring unit 22 may output a moving average value of the temperatures of the insulating member acquired at different timings as the temperature of the insulating member. For example, the temperature acquiring unit 22 included in the deterioration determination device 21 according to the first embodiment estimates the temperature of the stator coil, which is a conductor, from the measured values ​​of the phase voltages acquired from the voltage detection circuit 14 and the measured values ​​of the phase currents acquired from the current detection circuit 15 for each target period τ.

[0089] The temperature acquisition unit 22 calculates a moving average value of the estimated temperature of the stator coil, and uses the calculated moving average value as the temperature T iFor example, the i-th target period τ i In the above, the moving average value T' of the stator coil temperature estimated in the most recent j target periods τ is i_avg is expressed by the following equation (6).

[0090]

number

[0091] In order to prevent the deviation between the moving average temperature and the actual temperature, the moving average temperature T' of the stator coil temperature expressed by the following formula (7) is i_avg It is preferable to use:

[0092]

number

[0093] In this case, when a railcar equipped with the electric motor 91 starts operation for the first time, the deterioration determination device 21 starts the process of determining the degree of deterioration shown in Fig. 8. The process of step S11 is similar to the process performed by the deterioration determination device 21 shown in Fig. 3. The temperature acquisition unit 22 estimates the temperature of the stator coil, which is a conductor of the electric motor 91, from the coil resistance value calculated in step S11, calculates a moving average value of the temperature of the stator coil, estimates the calculated moving average value as the temperature of the insulating member, and outputs it to the damage degree determination unit 23 (step S22). The subsequent processes from step S13 to S16 are similar to the processes performed by the deterioration determination device 21 according to the first embodiment shown in Fig. 3.

[0094] By using the moving average of the conductor temperature as the temperature of the insulating material, it is possible to reduce the fluctuation of the estimated temperature of the insulating material when the temperature of the conductor fluctuates greatly. As a result, the damage degree, which indicates the elapsed time within the useful life LT corresponding to the temperature of the insulating material, is prevented from fluctuating greatly, and the accuracy of determining the degree of deterioration of the insulating material is improved.

[0095] As another example, the temperature acquisition unit 22 acquires the U-phase voltage command value Vu * , V phase voltage command value Vv * , and the W-phase voltage command value Vw * , and the excitation current command value id * and torque current command value iq * from the dq rotation coordinates to the three-phase coordinates based on the estimated position θ, to obtain a U-phase current command value, a V-phase current command value, and a W-phase current command value, and the coil resistance value may be calculated from each of the obtained command values. By calculating the coil resistance value from each command value, each detection circuit is not required, and it is possible to reduce the calculation load for calculating the resistance value from the detection value.

[0096] As another example, the temperature acquisition unit 22 may acquire a measurement value of at least one temperature sensor that measures the temperature of the conductor, and determine the temperature of the insulating member from the measurement value of the at least one temperature sensor. Specifically, the temperature acquisition unit 22 may use, as the temperature of the insulating member, an average value of measurements of a plurality of temperature sensors arranged in the longitudinal direction of the stator coil, in other words, in the extension direction of the rotating shaft of the electric motor 91. As the temperature sensor, for example, a thermocouple embedded between the stator coils may be used.

[0097] As another example, the temperature acquisition unit 22 may calculate the coil resistance values ​​of the U-phase stator coil, the V-phase stator coil, and the W-phase stator coil of the electric motor 91, and estimate the temperatures of the insulating member covering the U-phase stator coil, the insulating member covering the V-phase stator coil, and the insulating member covering the W-phase stator coil from the coil resistance values. In this case, the damage degree determination unit 23 may determine the damage degree for each of the insulating member covering the U-phase stator coil, the insulating member covering the V-phase stator coil, and the insulating member covering the W-phase stator coil. The determination unit 24 may determine the degree of deterioration of each of the insulating member covering the U-phase stator coil, the insulating member covering the V-phase stator coil, and the insulating member covering the W-phase stator coil.

[0098] In order to determine the temperature of the insulating member with higher accuracy, the temperature acquisition unit 22 may calculate the coil resistance value using an L-type equivalent circuit of the induction motor, and estimate the temperature of the stator coil from the calculated coil resistance value. For example, the coil resistance value Re of the U-phase stator coil may be u is expressed by the following formula (8). V in the following formula (8) pu indicates the phase voltage of the U phase, ω indicates the power supply angular frequency, and L 1u indicates the primary inductance, L2 indicates the secondary inductance, p indicates the number of poles of the motor 91, and TM indicates the torque of the motor 91. The primary inductance L 1u And the secondary inductance L2 may be the value at the time of shipping test.

[0099]

number

[0100] The power supply angular frequency ω is the excitation current command value Id * , torque current command value Iq * and the power supply angular frequency ω based on the rotation speed of the electric motor 91. The temperature acquisition unit 22 receives the torque command value τ * , and the excitation current command value Id * , torque current command value Iq * , and the power supply angular frequency ω calculated from the rotation speed of the electric motor 91. The temperature acquisition unit 22 acquires the torque command value τ * is used as the motor torque TM.

[0101] In the above formula (8), I u I' is a primary conversion current and is expressed by the following formula (9). u indicates the phase current of the U phase. I mu is the no-load current and is expressed by the following formula (10). mu is the composite magnetizing resistance, and is expressed by the following formula (11). muis the composite excitation reactance, and is expressed by the following equation (12). In this case, the impedance Z of the L-type equivalent circuit of the induction motor is expressed as Z=r using the imaginary unit j. mu +jx mu In the following equations (11) and (12), R m indicates the iron loss resistance, and L m indicates the excitation inductance. Iron loss resistance R m and the excitation inductance L m The value at the time of shipping test can be used.

[0102]

number

[0103]

number

[0104]

number

[0105]

number

[0106] The temperature acquisition unit 22 acquires the coil resistance value Re of the V-phase stator coil. v and the coil resistance value Re of the W-phase stator coil w Regarding the coil resistance Re u The temperature acquisition unit 22 calculates the coil resistance value Re as shown in the following formula (13). u ,Re v ,Re w From the above, the average coil resistance Re avg Calculate.

[0107]

number

[0108] The temperature acquisition unit 22 acquires the coil resistance average value Re avg The coil resistance Re that is the maximum when the value obtained by subtracting u ,Re v ,Re w is used as the coil resistance value Re. That is, the temperature acquisition unit 22 uses Re u -Re avg ,Re v -Re avg ,Re w -Re avg The coil resistance Re at which the value is maximum u ,Re v ,Re w is used as the coil resistance value Re. The temperature acquisition unit 22 estimates the temperature of the stator coil from the coil resistance value Re determined as described above.

[0109] The temperature acquisition unit 22 may calculate the coil resistance value using a T-type equivalent circuit of the induction motor, and estimate the temperature of the stator coil from the calculated coil resistance value.

[0110] The method of estimating the temperature of the stator coil is not limited to the above example. For example, the temperature acquisition unit 22 may estimate the temperature of the stator coil by calculating Re i-1 Instead of T', use the primary resistance Re0 measured at the time of shipment test. i-1 Alternatively, the temperature T0 measured at the time of shipping test may be used instead of the temperature T0. In detail, the temperature acquisition unit 22 uses the following equation (14) to obtain the temperature T' i may be calculated.

[0111]

number

[0112] The length of the target period τ is not limited to the above example, and may vary depending on parameters other than the operation command S1. As an example, the length of the target period τ may vary depending on the operating status of the equipment mounted on the railcar. Specifically, when a plurality of electric motors 91 are mounted on the railcar, the length of the useful life LT may vary depending on whether or not an abnormality occurs in at least one of the electric motors 91. For example, the damage degree determination unit 23 acquires information indicating the presence or absence of an abnormality in each electric motor 91 from an abnormality detector that detects an abnormality in the electric motors 91, and may make the target period τ=TP4 when an abnormality occurs in at least one of the electric motors 91 shorter than the target period τ=TP5 when an abnormality does not occur in any of the electric motors 91. When an abnormality occurs in any of the electric motors 91, it is necessary to increase the output of the electric motors 91 that are not otherwise abnormal in order to run the railcar at the target speed. This causes the temperature of the electric motors 91 that are not otherwise abnormal to rise.

[0113] Since the length of the useful life LT changes depending on whether or not an abnormality has occurred in at least any of the electric motors 91, the damage degree determining unit 23 can frequently determine the useful life LT corresponding to the temperature of the insulating member and determine the damage degree indicating the time that has elapsed within the useful life LT when the temperature of the stator coil of the electric motor 91 may increase. As a result, it becomes possible to accurately determine the time that has elapsed within the useful life LT as the target period τ elapses.

[0114] The insulating member to be discriminated by the deterioration discriminating device 21 is not limited to varnish. As an example, the insulating member may be a resin having insulating properties, such as polyimide, polyphenylene sulfide, or the like.

[0115] The deterioration determination device 21 may be implemented as one function of a train information management system. In addition, the deterioration determination device 21 may be provided in, for example, a train operation control center without being mounted on a railway vehicle.

[0116] The motor 91 may be either a three-phase induction motor or a three-phase synchronous motor. Furthermore, the motor 91 is not limited to a three-phase motor, and may be, for example, a single-phase motor or a DC motor. The motor 91 may be an inner rotor or an outer rotor.

[0117] The deterioration determination device 21 may be realized by a processing circuit 71 as shown in Fig. 10. The processing circuit 71 is connected to the voltage detection circuit 14, the current detection circuit 15, the output destination device 31, etc., via an interface circuit 72. When the processing circuit 71 is a dedicated hardware, the processing circuit 71 is, for example, a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC (Application Specific Integrated Circuit), an FPGA (Field Programmable Gate Array), or a combination of these. Each part of the deterioration determination device 21 may be realized by an individual processing circuit 71, or each part of the deterioration determination device 21 may be realized by a common processing circuit 71.

[0118] Some of the functions of the deterioration determination device 21 may be realized by dedicated hardware, and the other parts may be realized by software or firmware. For example, the temperature acquisition unit 22 may be realized by a processing circuit 71 shown in Fig. 10, and the damage level determination unit 23 and the determination unit 24 may be realized by the processor 61 shown in Fig. 2 reading and executing a program stored in the memory 62. Various aspects of the present disclosure are summarized below as appendices. (Appendix 1) a temperature acquisition unit that acquires a temperature of an insulating material covering a conductor; a damage degree determination unit that determines, for each target period, a damage degree indicating an elapsed time within a service life indicating a period during which the insulating member can be used, based on the temperature of the insulating member acquired by the temperature acquisition unit and a relationship between the temperature of the insulating member and a service life indicating a period during which the insulating member can be used; a determination unit that determines a degree of deterioration of the insulating member based on a cumulative damage degree that is a cumulative value of the damage degree determined for each target period; A deterioration determination device comprising: (Appendix 2) The determination unit determines a degree of deterioration of the insulating member based on the degree of damage determined for each target period from a time point at which the conductor is started to be used. 2. The deterioration determination device according to claim 1. (Appendix 3) The damage degree determination unit determines the damage degree, which is a ratio of the target period to the useful life, according to the temperature of the insulating member acquired by the temperature acquisition unit. 3. The deterioration determination device according to claim 1 or 2. (Appendix 4) The time period of interest is a time that is short compared to the thermal time constant of the conductor. 4. The deterioration determination device according to claim 3. (Appendix 5) The relationship between the temperature of the insulating member and the service life is such that as the temperature increases, the service life decreases. 5. A deterioration determination device according to any one of claims 1 to 4. (Appendix 6) The temperature acquisition unit acquires a temperature of the conductor and uses the acquired temperature of the conductor as a temperature of the insulating member. 6. A deterioration determination device according to any one of claims 1 to 5. (Appendix 7) the temperature acquisition unit estimates a resistance value of the conductor from a current flowing through the conductor and a potential of the conductor, estimates a temperature of the conductor from the estimated resistance value, and uses the estimated temperature of the conductor as a temperature of the insulating member. 7. The deterioration determination device according to claim 6. (Appendix 8) the temperature acquisition unit calculates a moving average value of the temperatures of the insulating member obtained at different times, and uses the moving average value as the temperature of the insulating member. 8. The deterioration determination device according to claim 6 or 7. (Appendix 9) the damage degree determination unit performs a correction for increasing the temperature of the insulating member acquired by the temperature acquisition unit for each of the target periods, and determines the damage degree from the corrected temperature of the insulating member and a relationship between the temperature of the insulating member and the useful life. 9. A deterioration determination device according to any one of appendix 1 to 8. (Appendix 10) a temperature acquisition unit that acquires a temperature of an insulating material covering a conductor; a damage degree determination unit that performs a correction for increasing the temperature of the insulating member acquired by the temperature acquisition unit for each target period, and determines a damage degree that indicates a time that has elapsed within the useful life that corresponds to the corrected temperature of the insulating member, based on the corrected temperature of the insulating member and a relationship between the temperature of the insulating member and a useful life that indicates a period during which the insulating member can be used; a determination unit that determines a degree of deterioration of the insulating member based on the damage degree determined for each target period; A deterioration determination device comprising: (Appendix 11) The temperature acquisition unit acquires a temperature of the insulating material covering the conductor used in equipment mounted on a railway vehicle. 11. A deterioration determination device according to any one of appendix 1 to 10. (Appendix 12) the damage level determination unit determines the damage level for each target period whose length changes in response to an operation command for the railway vehicle. 12. The deterioration determination device according to claim 11. (Appendix 13) a temperature acquisition unit that acquires a temperature of an insulating material that covers a conductor used in equipment mounted on a railway vehicle; a damage degree determination unit that determines, for each target period whose length changes in response to an operation command for the railway vehicle, a damage degree indicating an elapsed time within a useful life indicating a period during which the insulating member can be used, based on the temperature of the insulating member acquired by the temperature acquisition unit and a relationship between the temperature of the insulating member and a useful life indicating a period during which the insulating member can be used; a determination unit that determines a degree of deterioration of the insulating member based on the damage degree determined for each target period; A deterioration determination device comprising: (Appendix 14) The damage degree determination unit determines the damage degree for each target period whose length changes depending on the operation status of the device. 14. A deterioration determination device according to any one of appendixes 11 to 13. (Appendix 15) the temperature acquisition unit is mounted on the railway vehicle and acquires temperatures of the insulating members covering the conductors of a plurality of electric motors that generate propulsive force for the railway vehicle; the damage level determination unit determines the damage level for each of the target periods, the length of which varies depending on the presence or absence of an abnormality in the electric motor. 15. A deterioration determination device according to any one of appendixes 11 to 14. (Appendix 16) Obtain the temperature of the insulating material covering the conductor; determining, for each target period, a damage degree indicating the time that has elapsed within the useful life that corresponds to the obtained temperature of the insulating member, based on the obtained temperature of the insulating member and a relationship between the temperature of the insulating member and a useful life that indicates a period during which the insulating member can be used; determining a degree of deterioration of the insulating member based on a cumulative damage degree, which is a cumulative value of the damage degree determined for each target period; Deterioration determination method.

[0119] Various embodiments and modifications of the present disclosure are possible without departing from the broad spirit and scope of the present disclosure. The above-described embodiments are for explaining the present disclosure and do not limit the scope of the present disclosure. That is, the scope of the present disclosure is indicated by the claims, not the embodiments. Various modifications made within the scope of the claims and the scope of the disclosure equivalent thereto are considered to be within the scope of the present disclosure. [Explanation of symbols]

[0120] 11 power conversion device, 11a, 11b input terminals, 12 power conversion circuit, 13 power conversion circuit control unit, 14, 16 voltage detection circuit, 15, 17 current detection circuit, 21 deterioration determination device, 22 temperature acquisition unit, 23 damage degree determination unit, 24 determination unit, 31 output destination device, 60 bus, 61 processor, 62 memory, 63 interface, 71 processing circuit, 72 interface circuit, 91 electric motor, C1 capacitor, L1 reactor, S1 operation command, S2 power conversion control signal.

Claims

1. a temperature acquisition unit that acquires a temperature of an insulating material covering a conductor; a damage degree determination unit that performs a correction for increasing the temperature of the insulating member acquired by the temperature acquisition unit for each target period, and determines a damage degree that indicates a time that has elapsed within the useful life that corresponds to the corrected temperature of the insulating member, based on the corrected temperature of the insulating member and a relationship between the temperature of the insulating member and a useful life that indicates a period during which the insulating member can be used; a determination unit that determines a degree of deterioration of the insulating member based on the damage degree determined for each target period; A deterioration determination device comprising:

2. The temperature acquisition unit acquires a temperature of the insulating material covering the conductor used in equipment mounted on a railway vehicle. The deterioration determination device according to claim 1 .

3. the damage level determination unit determines the damage level for each target period whose length changes in response to an operation command for the railway vehicle. The deterioration determination device according to claim 2 .

4. a temperature acquisition unit that acquires a temperature of an insulating material that covers a conductor used in equipment mounted on a railway vehicle; a damage degree determination unit that determines, for each target period whose length changes in response to an operation command for the railway vehicle, a damage degree indicating an elapsed time within a useful life indicating a period during which the insulating member can be used, based on the temperature of the insulating member acquired by the temperature acquisition unit and a relationship between the temperature of the insulating member and a useful life indicating a period during which the insulating member can be used; a determination unit that determines a degree of deterioration of the insulating member based on the damage degree determined for each target period; A deterioration determination device comprising:

5. The determination unit determines a degree of deterioration of the insulating member based on the degree of damage determined for each target period from a time point at which the conductor is started to be used. The deterioration determination device according to any one of claims 1 to 4.

6. The damage degree determination unit determines the damage degree, which is a ratio of the target period to the useful life, according to the temperature of the insulating member acquired by the temperature acquisition unit. The deterioration determination device according to any one of claims 1 to 4.

7. The time period of interest is a time that is short compared to the thermal time constant of the conductor. The deterioration determination device according to claim 6.

8. The relationship between the temperature of the insulating member and the service life is such that as the temperature increases, the service life decreases. The deterioration determination device according to any one of claims 1 to 4.

9. The temperature acquisition unit acquires a temperature of the conductor and uses the acquired temperature of the conductor as a temperature of the insulating member. The deterioration determination device according to any one of claims 1 to 4.

10. the temperature acquisition unit estimates a resistance value of the conductor from a current flowing through the conductor and a potential of the conductor, estimates a temperature of the conductor from the estimated resistance value, and uses the estimated temperature of the conductor as a temperature of the insulating member. The deterioration determination device according to claim 9.

11. the temperature acquisition unit calculates a moving average value of the temperatures of the insulating member obtained at different times, and uses the moving average value as the temperature of the insulating member. The deterioration determination device according to claim 9.

12. the damage degree determination unit performs a correction for increasing the temperature of the insulating member acquired by the temperature acquisition unit for each of the target periods, and determines the damage degree from the corrected temperature of the insulating member and a relationship between the temperature of the insulating member and the useful life. The deterioration determination device according to claim 4.

13. The damage degree determination unit determines the damage degree for each target period whose length changes depending on the operation status of the device. The deterioration determination device according to any one of claims 2 to 4 and 12.

14. the temperature acquisition unit is mounted on the railway vehicle and acquires temperatures of the insulating members covering the conductors of a plurality of electric motors that generate propulsive force for the railway vehicle; the damage level determination unit determines the damage level for each of the target periods, the length of which varies depending on the presence or absence of an abnormality in the electric motor. The deterioration determination device according to any one of claims 2 to 4 and 12.

15. Obtain the temperature of the insulating material covering the conductor; performing a correction for each target period to increase the temperature of the insulating member, and determining a damage degree indicating the time that has elapsed within the useful life that corresponds to the corrected temperature of the insulating member, based on the corrected temperature of the insulating member and a relationship between the temperature of the insulating member and a useful life that indicates a period during which the insulating member can be used; determining a degree of deterioration of the insulating member based on the degree of damage determined for each target period; Deterioration determination method.

16. Acquiring the temperature of an insulating material covering a conductor used in equipment mounted on a railway vehicle, determining, for each target period whose length changes in response to an operation command for the railway vehicle, a damage degree indicating an amount of time that has elapsed within a useful life indicating a period during which the insulating member can be used, based on the obtained temperature of the insulating member and a relationship between the temperature of the insulating member and a useful life indicating a period during which the insulating member can be used; determining a degree of deterioration of the insulating member based on the degree of damage determined for each target period; Deterioration determination method.

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