Magnet temperature information output device, rotating electrical machine, and magnet temperature acquisition device

Abstract

The magnet temperature information output device comprises an element unit arranged on a rotor, an element unit arranged on a stator, a resistor element and an output part. The element unit comprises a temperature sensing element and a coil. The resistance of the temperature sensing element changes according to the temperature of the permanent magnet. The coil is electrically connected with the temperature sensing element. The element unit includes a coil. The coils are magnetically coupled to each other. The resistive element is electrically connected to the element unit. The output unit is electrically connected to the element unit and the resistive element. The output unit outputs, as temperature information relating to the temperature of the permanent magnet, an electric signal corresponding to the magnitude of the voltage drop generated in the resistive element.

Description

Technical Field

[0001] The present disclosure relates to a magnet temperature information output device, a rotating electrical machine provided with the magnet temperature information output device, and a magnet temperature acquisition device including the magnet temperature information output device. Background Art

[0002] A magnet temperature information output device is known, which is provided in a rotating electric machine having a stator and a rotor equipped with a permanent magnet, and outputs temperature information related to the temperature of the permanent magnet (for example, refer to Japanese Patent Gazette No. 2021-39019). The magnet temperature information output device comprises: a temperature sensing element, a first coil, a second coil, and an output unit. The temperature sensing element is provided on the rotor, and the resistance changes according to the temperature of the permanent magnet. The first coil is electrically connected to the temperature sensing element. The second coil is provided on the stator and is magnetically coupled to the first coil. The output unit outputs an electrical signal corresponding to the magnitude of the current flowing through the second coil. Summary of the invention

[0003] One aspect of the present disclosure is to provide a magnet temperature information output device that outputs temperature information related to the temperature of a permanent magnet as an electrical signal related to voltage. Another aspect of the present disclosure is to provide a rotating electrical machine provided with the magnet temperature information output device. Another aspect of the present disclosure is to provide a magnet temperature acquisition device that includes the magnet temperature information output device.

[0004] A magnet temperature information output device of one embodiment is provided in a rotating electric machine having a stator and a rotor equipped with a permanent magnet, and outputs temperature information related to the temperature of the permanent magnet. The magnet temperature information output device comprises: a first element unit provided on the rotor, a second element unit provided on the stator, a resistance element, and an output unit. The first element unit includes a temperature sensing element and a first coil. The resistance of the temperature sensing element changes according to the temperature of the permanent magnet. The first coil is electrically connected to the temperature sensing element. The second element unit includes a second coil. The second coil is magnetically coupled to the first coil. The resistance element is electrically connected to the second element unit. The output unit is electrically connected to the second element unit and the resistance element. The output unit outputs an electrical signal corresponding to the magnitude of a voltage drop generated in the resistance element as temperature information.

[0005] In one of the above-mentioned methods, the magnet temperature information output device includes a resistor element electrically connected to the second element unit. Because the second coil included in the second element unit is magnetically coupled to the first coil, power is supplied to the first coil. Because the resistance of the temperature-sensitive element electrically connected to the first coil changes according to the temperature of the permanent magnet, the current flowing through the second coil changes according to the change in the resistance of the temperature-sensitive element. The magnitude of the voltage drop generated in the resistor element changes due to the change in the current flowing through the second coil. The output unit outputs an electrical signal corresponding to the magnitude of the voltage drop generated in the resistor element. Therefore, the electrical signal output from the output unit changes according to the temperature of the permanent magnet. That is, in one of the above-mentioned methods, temperature information related to the temperature of the permanent magnet is output from the output unit as an electrical signal related to voltage. As described above, one of the above-mentioned methods outputs temperature information related to the temperature of the permanent magnet as an electrical signal related to voltage.

[0006] In one embodiment, the resistor element may have Z o 0.50 ×Z 150 0.28 Above Z o 0.50 ×Z 150 0.71 Here, Z 150 It may also be the combined impedance of the first element unit and the second element unit when the first coil and the second coil are magnetically coupled and the temperature of the temperature sensing element is 150°C. o It may be a combined impedance of the first element unit and the second element unit in a state where the first coil and the second coil are magnetically coupled and the temperature sensing element is separated from the first element unit.

[0007] The resistor element has a Z o 0.50 ×Z 150 0.28 Above Z o 0.50 ×Z 150 0.71 The following resistor structure outputs temperature information related to the temperature of the permanent magnet with high accuracy.

[0008] In the above-described aspect, the second element unit may include a capacitor that forms an LC resonance circuit with the second coil.

[0009] The configuration in which the second element unit includes a capacitor forming an LC resonance circuit with the second coil detects the change in resistance of the temperature sensing element with high accuracy. Therefore, this configuration outputs temperature information related to the temperature of the permanent magnet with high accuracy.

[0010] In the above-described aspect, the first element unit may include a capacitor that forms an LC resonance circuit with the first coil.

[0011] The configuration in which the first element unit includes a capacitor forming an LC resonance circuit with the first coil can detect the change in resistance of the temperature sensing element with high accuracy. Therefore, this configuration can output temperature information related to the temperature of the permanent magnet with high accuracy.

[0012] In the above-mentioned aspect, the first element unit may further include a capacitor constituting an LC resonance circuit with the first coil. The second element unit may further include a capacitor constituting an LC resonance circuit with the second coil.

[0013] The configuration in which the first element unit and the second element unit include capacitors outputs temperature information related to the temperature of the permanent magnet with high accuracy.

[0014] In the above-described aspect, a voltage having a frequency lower than a predetermined resonance frequency for exciting the first coil may be applied to the second coil.

[0015] The configuration in which a voltage having a frequency lower than a predetermined resonance frequency for exciting the first coil is applied to the second coil outputs temperature information related to the temperature of the permanent magnet with high accuracy.

[0016] In the above-described aspect, a difference between the frequency of the voltage applied to the second coil and the predetermined resonance frequency may be 5 kHz or more and 30 kHz or less.

[0017] A configuration in which the difference between the frequency of the voltage applied to the second coil and the resonance frequency is 5 kHz or more and 30 kHz or less outputs temperature information related to the temperature of the permanent magnet with high accuracy.

[0018] A rotating electrical machine according to another embodiment is provided with the above-mentioned magnet temperature information output device.

[0019] In the above-mentioned other aspect, since the above-mentioned magnet temperature information output device is provided, the temperature information related to the temperature of the permanent magnet is output as an electric signal related to the voltage.

[0020] In the above-mentioned other aspect, the first coil and the second coil may be arranged so as to face each other in the rotation axis direction of the rotor when the rotor is at a predetermined rotation angle position.

[0021] In the above another embodiment, the rotor may include a rotor core. The entire permanent magnet and at least a portion of the first coil may be disposed in the rotor core. The permanent magnet may include a pair of faces perpendicular to the direction of the rotation axis of the rotor. The temperature sensing element may be disposed to contact a face of the pair of faces that is located close to the second coil when the rotor is at a predetermined rotation angle position.

[0022] In the above another embodiment, the rotor core may include a pair of end faces perpendicular to the rotor rotation axis direction. The end face of the pair of end faces located near the second coil may be coplanar with one end of the first coil in the rotor rotation axis direction.

[0023] In the above another embodiment, the rotor core may also include a plurality of steel plates and plates stacked along the rotation axis direction, and the plurality of steel plates may also be magnetic. The plates may also be conductive. The plates may also be arranged on the steel plates located at the outermost position in the rotation axis direction of the rotor and located near the second coil among the plurality of steel plates. The first coil may also be embedded in the plates.

[0024] A magnet temperature acquisition device according to still another embodiment includes the magnet temperature information output device described above, acquires an electrical signal output from the magnet temperature information output device, and obtains the temperature of the permanent magnet based on the acquired electrical signal.

[0025] The above-mentioned still another aspect includes the above-mentioned magnet temperature information output device, thereby obtaining the temperature of the permanent magnet based on the electric signal related to the voltage.

[0026] The present disclosure will be more fully understood from the detailed description given hereinafter and the accompanying drawings, which are given by way of illustration only and thus should not be considered as limiting the present disclosure.

[0027] The further applicable scope of the present disclosure becomes clear from the detailed description given below. However, it should be understood that the detailed description and specific examples, although indicating examples of the present disclosure, are only given by way of illustration, and various changes and modifications within the spirit and scope of the present disclosure are obvious to those skilled in the art. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic diagram showing the structure of a magnet temperature information output device and a rotating electrical machine according to one embodiment.

[0029] Figure 2 This is a circuit diagram showing an example of a magnet temperature information output device.

[0030] Figure 3 This is a circuit diagram showing an equivalent circuit used when setting the resistance of a resistor element.

[0031] Figure 4 This is a circuit diagram showing an equivalent circuit used when setting the resistance of a resistor element.

[0032] Figure 5 It is a diagram showing a cross-sectional structure of a rotor core.

[0033] Figure 6This is a circuit diagram showing another example of the magnet temperature information output device.

[0034] Figure 7 This is a circuit diagram showing an equivalent circuit used when setting the resistance of a resistor element.

[0035] Figure 8 This is a circuit diagram showing an equivalent circuit used when setting the resistance of a resistor element.

[0036] Fig. 9 This is a circuit diagram showing still another example of the magnet temperature information output device.

[0037] Fig.10 This is a circuit diagram showing an equivalent circuit used when setting the resistance of a resistor element.

[0038] Fig.11 This is a circuit diagram showing an equivalent circuit used when setting the resistance of a resistor element.

[0039] Fig.12 It is a diagram showing a cross-sectional structure of a rotor core.

[0040] Fig.13 It is a diagram showing a cross-sectional structure of a rotor core.

[0041] Fig.14 This is a circuit diagram showing an equivalent circuit used when obtaining the relationship between the resistance of a resistor element and the accuracy of temperature information.

[0042] Fig.15 This is a graph showing the relationship between the resistance of a resistor element and the accuracy of temperature information.

[0043] Fig.16 This is a graph showing the relationship between the resistance of a resistor element and the accuracy of temperature information.

[0044] Fig.17 This is a graph showing the relationship between the voltage drop generated in a resistor element and the temperature.

[0045] Fig.18 This is a graph showing the relationship between the voltage drop generated in a resistor element and the temperature.

[0046] Fig.19 This is a graph showing the relationship between the voltage drop generated in a resistor element and the temperature.

[0047] Fig. 20 This is a graph showing the relationship between the voltage drop generated in a resistor element and the temperature.

[0048] Fig.21 This is a graph showing the relationship between the voltage drop generated in a resistor element and the temperature.

[0049] Fig. 22 This is a graph showing the relationship between the voltage drop generated in a resistor element and the temperature.

[0050] Fig.23 This is a graph showing the relationship between the voltage drop generated in a resistor element and the temperature. DETAILED DESCRIPTION

[0051] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. In the following description, the same reference numerals are used for the same elements or elements having the same functions, and repeated descriptions are omitted.

[0052] Reference Figure 1 Next, the structure of the magnet temperature information output device 1 according to the present embodiment and the rotating electrical machine MT provided with the magnet temperature information output device 1 will be described. Figure 1 It is a schematic diagram showing the configuration of the magnet temperature information output device and the rotating electrical machine according to the present embodiment.

[0053] like Figure 1 As shown, the magnet temperature information output device 1 is provided on the rotating electrical machine MT. The rotating electrical machine MT includes, for example, an electric motor. The electric motor includes, for example, an IPM motor or an SPM motor. Figure 1 As shown, the rotary electric machine MT includes a stator 10 and a rotor 20 . The rotor 20 is located inside the stator 10 .

[0054] The rotor 20 includes a shaft 21, a rotor core 23, and a plurality of permanent magnets 25. The shaft 21 is cylindrical. The rotor core 23 is cylindrical. An axial hole for inserting the shaft 21 is formed on the rotor core 23. The shaft 21 and the rotor core 23 rotate integrally around the central axis of the shaft 21. Each permanent magnet 25 is arranged on the rotor core 23 in such a manner that its extension direction is parallel to the central axis of the shaft 21. "The extension direction of the permanent magnet 25 is parallel to the central axis of the shaft 21" does not necessarily mean that the extension direction of the permanent magnet 25 is parallel to the central axis of the shaft 21. The extension direction of the permanent magnet 25 is parallel to the central axis of the shaft 21, including a slight difference within a predetermined range, a manufacturing error, or a measurement error within the angle formed by the extension direction of the permanent magnet 25 and the central axis of the shaft 21. When the slight difference within a predetermined range is included in the angle formed by the extension direction of the permanent magnet 25 and the central axis of the shaft 21, the extension direction of the permanent magnet 25 is parallel to the central axis of the shaft 21, for example, including the angle formed within the range of ±2 degrees. The central axis of the shaft 21 includes the rotation axis of the rotor 20. The direction in which the rotation axis of the rotor 20 extends includes the rotation axis direction D of the rotor 20. One magnet may constitute one pole, or multiple magnets may constitute one pole. In the case where one magnet constitutes one pole, multiple permanent magnets 25 are arranged at equal angular intervals with respect to the rotation axis of the rotor 20. "Equal angular intervals" does not necessarily mean that the angular intervals are consistent. The angular interval equality includes slight differences within a predetermined range, and manufacturing errors or measurement errors are included in the difference in angular intervals. In the case where the slight differences within a predetermined range are included in the difference in angular intervals, the angular intervals of the permanent magnets 25 with respect to the rotation axis of the rotor 20 are equal, for example, including that the angular intervals of the permanent magnets 25 with respect to the rotation axis of the rotor 20 are within the range of ±10% relative to the average angular interval of all angular intervals.

[0055] When the rotating electrical machine MT includes an IPM motor, a plurality of permanent magnets 25 are arranged in the rotor core 23. When the rotating electrical machine MT includes an SPM motor, a plurality of permanent magnets 25 are arranged on the surface of the rotor core 23. Each permanent magnet 25 includes a rare earth permanent magnet. Each permanent magnet 25 includes, for example, a neodymium sintered magnet. Each permanent magnet 25 may include a sintered magnet other than a rare earth permanent magnet, or may include a magnet other than a sintered magnet. The magnet other than the sintered magnet includes, for example, a bonded magnet or a hot-processed magnet.

[0056] The stator 10 includes a cylindrical stator core (not shown) arranged in a manner surrounding the outer circumference of the rotor 20 and a plurality of stator coils 11. The stator 10 may further include a stator core, a plurality of stator coils 11, and a housing surrounding the rotor 20. An air gap of uniform width is provided between the stator 10 and the rotor 20. "Uniform width" does not necessarily mean that the widths of the air gaps between the stator 10 and the rotor 20 are uniform. The uniformity of the widths of the air gaps between the stator 10 and the rotor 20 includes a slight difference, a manufacturing error, or a measurement error within a predetermined range in the difference between the widths. When the difference between the widths includes a slight difference within a predetermined range, the uniformity of the widths of the air gaps between the stator 10 and the rotor 20 includes, for example, that the widths of the air gaps between the stator 10 and the rotor 20 are within a range of ±10% relative to the average width of the widths of all the air gaps. The stator core holds a plurality of stator coils 11. Each stator coil 11 is arranged on the inner circumference of the stator core. The plurality of stator coils 11 are arranged at equal angular intervals on the rotation axis of the rotor 20 .

[0057] The rotating electrical machine MT is connected to a control circuit 41. The control circuit 41 is connected to a power supply 43. The control circuit 41 adjusts the drive current from the power supply 43 and supplies three-phase AC current to each stator coil 11. The control circuit 41 controls the value of the three-phase AC current supplied to each stator coil 11. The control circuit 41 includes, for example, an inverter circuit. By supplying three-phase AC current to each stator coil 11, each stator coil 11 forms a rotating magnetic field that rotates the rotor 20. The power supply 43 includes, for example, an electrical energy storage device. The electrical energy storage device includes, for example, a secondary battery or a capacitor.

[0058] Next, refer to Figure 2 , the structure of the magnet temperature information output device 1 is described in more detail. Figure 2 This is a circuit diagram showing an example of a magnet temperature information output device.

[0059] The magnet temperature information output device 1 outputs temperature information related to the temperature of the permanent magnet 25. In order to realize this function, the magnet temperature information output device 1 includes an element unit 50, an element unit 60, a resistance element 70, and an output unit 80. In the present embodiment, the number of the element unit 50 is one, and the number of the element unit 60 is also one. The element unit 50 is provided on the rotor 20. The element unit 60 is provided on the stator 10. The element unit 60 is provided on the stator core, for example. The element unit 50 and the element unit 60 are arranged so as to face each other in a direction parallel to the rotation axis of the rotor 20 when the rotor 20 is at a predetermined rotation angle position. "A direction parallel to the rotation axis of the rotor 20" does not necessarily mean only a direction parallel to the rotation axis of the rotor 20. The direction parallel to the rotation axis of the rotor 20 includes a direction in which a slight difference, a manufacturing error, or a measurement error within a predetermined range is included in the angle formed with the rotation axis of the rotor 20. When the slight difference within the preset range is included in the angle formed with the rotation axis of the rotor 20, the direction parallel to the rotation axis of the rotor 20 includes, for example, a direction in which the angle is within the range of ±2 degrees.

[0060] like Figure 2 As shown, the element unit 50 includes a temperature sensing element 51 and a coil 53. The temperature sensing element 51 and the coil 53 are arranged on the rotor 20. The temperature sensing element 51 is arranged on at least one permanent magnet 25 among the plurality of permanent magnets 25. In the present embodiment, the temperature sensing element 51 is arranged only on one permanent magnet 25. The temperature sensing element 51 is configured in a manner of being connected to the permanent magnet 25. The temperature sensing element 51 may also be configured near the permanent magnet 25. The resistance of the temperature sensing element 51 changes according to the temperature of the permanent magnet 25. As the temperature of the permanent magnet 25 rises, the resistance of the temperature sensing element 51 decreases. The temperature sensing element 51 includes, for example, a thermistor or a Hall element. The thermistor includes, for example, an NTC thermistor. The coil 53 is electrically connected to the temperature sensing element 51. In the present embodiment, both ends of the coil 53 are electrically connected to both ends of the temperature sensing element 51.

[0061] The element unit 60 includes a coil 61 and a capacitor 63. The coil 61 is arranged on the stator 10 so as to face the coil 53 in the rotation axis direction D of the rotor 20 when the rotor 20 is at a predetermined rotation angle position. The coil 53 and the coil 61 are arranged so as to face each other in the rotation axis direction D of the rotor 20 when the rotor 20 is at a predetermined rotation angle. The coil 61 is magnetically coupled to the coil 53. The coil 61 is electrically connected to the AC power supply PS. The AC power supply PS includes, for example, an inverter. An AC signal of a predetermined frequency is applied from the AC power supply PS to the coil 61. An AC voltage is applied from the AC power supply PS to the coil 61. The predetermined frequency is higher than the driving frequency of the rotating electric machine MT. The predetermined frequency is, for example, 10 to 2000 times the driving frequency of the rotating electric machine MT. The capacitor 63 and the coil 61 form an LC resonant circuit. The capacitor 63 may also form an LC resonant circuit with the coil 53 and the coil 61. The capacitor 63 is inserted, for example, in a manner connected in parallel with the coil 61. For example, when the coil 53 includes a first coil, the coil 61 includes a second coil. For example, when the element unit 50 includes a first element unit, the element unit 60 includes a second element unit.

[0062] For example, the above-mentioned prescribed frequency may be lower than the prescribed resonant frequency of the exciting coil 53. That is, the frequency of the voltage applied to the coil 61 may be lower than the prescribed resonant frequency of the exciting coil 53. The above-mentioned prescribed resonant frequency is, for example, the resonant frequency of the circuit in the magnet temperature information output device 1 that equivalently represents the magnetic coupling between the coil 53 and the coil 61 and the temperature of the temperature sensing element 51 is a prescribed temperature. In the present embodiment, the above-mentioned circuit is a circuit including the temperature sensing element 51, the coil 53, the coil 61 and the capacitor 63. The above-mentioned prescribed temperature is, for example, room temperature. The room temperature is, for example, not less than 15°C and not more than 30°C. In the present embodiment, the above-mentioned prescribed temperature is 25°C.

[0063] The resistance element 70 is electrically connected to the element unit 60. The resistance element 70 may also be electrically connected to the coil 61. In the present embodiment, the resistance element 70 is provided on the stator 10 and inserted between the coil 61 and the AC power supply PS.

[0064] The output unit 80 is electrically connected to the element unit 60 and the resistor element 70. The output unit 80 may also be electrically connected to the coil 61. That is, the coil 61 may also be electrically connected to the resistor element 70 and the output unit 80. In the present embodiment, the output unit 80 is provided on the stator 10. The output unit 80 outputs an electrical signal corresponding to the magnitude of the voltage drop generated in the resistor element 70. The output unit 80 may also output an electrical signal indicating the magnitude of the voltage drop generated in the resistor element 70. The output unit 80 includes, for example, a voltmeter. The voltmeter may also be composed of, for example, a computing device including a CPU (Central Processing Unit), a ROM (Read Only Memory) and a RAM (Random Access Memory). The computing device may also be, for example, a microcomputer. In this case, the voltmeter outputs an electrical signal corresponding to the magnitude of the voltage drop generated in the resistor element 70 by loading the program stored in the ROM into the RAM and executing it by the CPU.

[0065] A magnetic flux corresponding to the AC voltage applied from the AC power supply PS is generated in the coil 61. When the rotor 20 rotates and the coil 61 and the coil 53 approach each other, the magnetic flux generated in the coil 61 passes through the coil 53. When the magnetic flux generated in the coil 61 passes through the coil 53, electric power corresponding to the change in the magnetic flux passing through the coil 53 is generated in the coil 53. That is, when the rotor 20 rotates and the coil 61 and the coil 53 approach each other, the coil 61 is magnetically coupled with the coil 53. Alternatively, it can be said that the coil 61 excites the coil 53 and supplies electric power to the coil 53.

[0066] Since the resistance of the temperature sensing element 51 changes according to the temperature of the permanent magnet 25, the magnetic flux generated in the coil 61 changes according to the change in the resistance of the temperature sensing element 51. Therefore, the current flowing through the coil 61 changes. The magnitude of the voltage drop generated in the resistance element 70 changes due to the change in the current flowing through the coil 61.

[0067] When the temperature of the permanent magnet 25 rises and the resistance of the temperature sensing element 51 decreases, the magnetic flux generated in the coil 61 increases. Therefore, the current flowing through the coil 61 increases, and the magnitude of the voltage drop generated in the resistance element 70 also increases. When the temperature of the permanent magnet 25 decreases and the resistance of the temperature sensing element 51 increases, the magnetic flux generated in the coil 61 decreases. Therefore, the current flowing through the coil 61 decreases, and the magnitude of the voltage drop generated in the resistance element 70 also decreases. That is, the magnitude of the voltage drop generated in the resistance element 70 increases due to the increase in the temperature of the permanent magnet 25. Similarly, the magnitude of the voltage drop generated in the resistance element 70 decreases due to the decrease in the temperature of the permanent magnet 25.

[0068] The output unit 80 detects the magnetic flux generated in the coil 61 as the magnitude of the voltage drop generated in the resistor element 70. The magnitude of the voltage drop detected by the output unit 80 corresponds to the change in the resistance of the temperature sensing element 51, that is, the change in the temperature of the permanent magnet 25. Therefore, the electrical signal output from the output unit 80 includes temperature information related to the temperature of the permanent magnet 25. That is, the output unit 80 outputs the electrical signal corresponding to the magnitude of the voltage drop generated in the resistor element 70 as the above-mentioned temperature information. As a result, the temperature information related to the temperature of the permanent magnet 25 is wirelessly transmitted between the element unit 50 and the output unit 80 via the element unit 60.

[0069] The electric signal output from the output unit 80 is input as the temperature information to the control circuit 41. The control circuit 41 acquires the electric signal corresponding to the magnitude of the voltage drop generated in the resistor 70, which is output from the magnet temperature information output device 1. The control circuit 41 obtains the temperature of the permanent magnet 25 based on the acquired electric signal. That is, in this embodiment, the control circuit 41 functions as a magnet temperature acquisition device.

[0070] The control circuit 41 obtains the temperature of the permanent magnet 25, for example, as follows. First, the control circuit 41 refers to data indicating the relationship between the electric signal corresponding to the magnitude of the voltage drop generated in the resistor 70 and the temperature. The data may be stored in the control circuit 41 or in an external server different from the control circuit 41. Next, the control circuit 41 obtains the temperature corresponding to the obtained electric signal from the above data as the temperature of the permanent magnet 25.

[0071] The control circuit 41 controls the driving state of the rotating electrical machine MT based on the obtained temperature of the permanent magnet 25. For example, the control circuit 41 controls the driving state of the rotating electrical machine MT as follows. When the control circuit 41 determines that the obtained temperature of the permanent magnet 25 has risen to a predetermined first threshold value, the control circuit 41 controls the supply of power to limit the rotation speed of the rotating electrical machine MT. When the control circuit 41 determines that the obtained temperature of the permanent magnet 25 has dropped to a predetermined second threshold value that is smaller than the first threshold value, the control circuit 41 controls the supply of power to release the limitation on the rotation speed of the rotating electrical machine MT.

[0072] The control circuit 41 may also control the driving state of the rotating electrical machine MT as follows. That is, the control circuit 41 may also control, for example, the driving frequency input to the rotating electrical machine MT based on the temperature of the obtained permanent magnet 25. When the control circuit 41 determines that the temperature of the obtained permanent magnet 25 has risen to a predetermined first threshold value, the control circuit 41 controls to reduce the driving frequency so as to limit the rotation speed of the rotating electrical machine MT. When the control circuit 41 determines that the temperature of the obtained permanent magnet 25 has dropped to a predetermined second threshold value that is smaller than the above-mentioned first threshold value, the control circuit 41 controls to increase the driving frequency so as to release the limitation on the rotation speed of the rotating electrical machine MT.

[0073] The control circuit 41 includes, for example, a CPU (Central Processing Unit), a ROM (Read Only Memory), and a RAM (Random Access Memory). The control circuit 41 loads a program stored in the ROM into the RAM and executes the program by the CPU, thereby obtaining the temperature of the permanent magnet 25 and controlling the driving state of the rotating electrical machine MT.

[0074] Next, refer to Figure 3 and Figure 4 , the resistance of the resistor element 70 will be described. Figure 3 and Figure 4 This is a circuit diagram showing an equivalent circuit used when setting the resistance of a resistor element.

[0075] As described above, the resistance of the temperature sensing element 51 changes according to the temperature of the permanent magnet 25. According to the change in the resistance of the temperature sensing element 51, the range of the resistance of the resistor 70 for accurately detecting the change in the temperature of the permanent magnet 25 also changes. In the present embodiment, the resistance of the resistor 70 is set within the range for accurately detecting the change in the temperature of the permanent magnet 25.

[0076] Hereinafter, the range of the resistance of the resistor element 70 that can detect the change in the temperature of the permanent magnet 25 with high accuracy is referred to as "the first range of the resistance of the resistor element 70", and the range of the resistance of the resistor element 70 that can detect the change in the temperature of the permanent magnet 25 with even higher accuracy is referred to as "the second range of the resistance of the resistor element 70". Furthermore, hereinafter, the resistance of the resistor element 70 that can detect the change in the temperature of the permanent magnet 25 with even higher reliability and accuracy is sometimes referred to as "the first resistance of the resistor element 70".

[0077] The impedance of the magnet temperature information output device 1 as a whole including the element unit 50 and the element unit 60 also changes according to the change in the resistance of the temperature sensing element 51. That is, the combined impedance of the element unit 50 and the element unit 60 also changes according to the change in the resistance of the temperature sensing element 51. Therefore, the present inventors focused on the relationship between the first range of the resistance of the resistor element 70 and the combined impedance of the element unit 50 and the element unit 60. In order to clarify the relationship between the first range of the resistance of the resistor element 70 and the combined impedance of the element unit 50 and the element unit 60, the present inventors used Figure 3 The equivalent circuit EC1 is an experiment of equivalent circuit EC1 shown in FIG. The equivalent circuit EC1 is a circuit equivalent to the circuit including the temperature sensing element 51, the coil 53, the coil 61 and the capacitor 63 in the magnet temperature information output device 1. Therefore, the equivalent circuit EC1 includes elements corresponding to the temperature sensing element 51, the coil 53, the coil 61 and the capacitor 63.

[0078] In this embodiment, if Figure 3 As shown, the equivalent circuit EC1 includes an element R1, an element L1, an element R2, an element L2, an element L3, an element R3, and an element C1. The element R1 corresponds to the temperature sensing element 51. In the present embodiment, the element R1 includes an element corresponding to the resistance of the temperature sensing element 51. The elements L1 and R2 correspond to the coil 53. In the present embodiment, the element L1 includes an element corresponding to the inductance of the coil 53, and the element R2 includes an element corresponding to the resistance of the coil 53. In the equivalent circuit EC1, the element R1 is electrically connected to the elements L1 and R2.

[0079] Elements L3 and R3 correspond to coil 61. In the present embodiment, element L3 includes an element corresponding to the inductance of coil 61, and element R3 includes an element corresponding to the resistance of coil 61. Element R3 is connected in series with element L3. Element L2 corresponds to the magnetic coupling between coil 53 and coil 61. In the present embodiment, element L3 includes an element corresponding to the mutual inductance of coil 53 and coil 61. Element C1 corresponds to capacitor 63. In the present embodiment, element C1 includes an element corresponding to the capacitance component of capacitor 63. Element C1 is connected in parallel with element L3. In the equivalent circuit EC1, the end close to element C1 is untied. In the equivalent circuit EC1, the portion composed of element R1 and elements R2 and L1 corresponds to element unit 50, and the portion composed of elements L3, R3 and element C1 corresponds to element unit 60.

[0080] While changing the temperature of the element R1 corresponding to the temperature sensing element 51, the present inventors and others calculated the relationship between the impedance in the equivalent circuit EC1 at the temperature and the first range of resistance of the resistor 70 when the temperature sensing element 51 is at the temperature. While changing the temperature of the element R1 corresponding to the temperature sensing element 51, the present inventors and others calculated the relationship between the impedance in the equivalent circuit EC1 at the temperature and the second range of resistance of the resistor 70 when the temperature sensing element 51 is at the temperature. While changing the temperature of the element R1 corresponding to the temperature sensing element 51, the present inventors and others calculated the relationship between the impedance in the equivalent circuit EC1 at the temperature and the first range of resistance of the resistor 70 when the temperature sensing element 51 is at the temperature. As a result, the present inventors and others found that the first range of resistance of the resistor 70 is a×Z1 T 0.28 Above a×Z1 T 0.71 Below. Z1 T is the combined impedance of the element unit 50 and the element unit 60 in the equivalent circuit EC1 when the temperature of the element R1 is T°C. The inventors of the present invention have found that the second range of the resistance of the resistance element 70 is a×Z1 T 0.38 Above a×Z1 T 0.63 The present inventors have found that the first resistance of the resistor element 70 is a×Z1 T 0.50 Here, "a" represents a proportionality factor set for each circuit.

[0081] Next, the inventors conducted research to calculate the proportionality coefficient a. As a result, they found that the proportionality coefficient a is the same as the combined impedance of the element unit 50 and the element unit 60 when the temperature sensing element 51 is separated from the element unit 50. Therefore, the inventors obtained Figure 4 The composite impedance Z2 of the element unit 50 and the element unit 60 in the equivalent circuit EC2 shown is calculated based on the composite impedance Z2. The equivalent circuit EC2 is a circuit that equivalently represents a circuit in which the temperature sensing element 51 is separated from the circuit including the temperature sensing element 51, the coil 53, the coil 61, and the capacitor 63 in the magnet temperature information output device 1. In the equivalent circuit EC2, the element R1 corresponding to the temperature sensing element 51 included in the equivalent circuit EC1 is eliminated. Therefore, in the equivalent circuit EC2, the proportionality coefficient a and the composite impedance Z2 satisfy the relationship Z2 = a × Z2 0.50 That is, the proportionality coefficient a is expressed as Z2 using the synthetic impedance Z2 0.50 As described above, it can be understood that in the magnet temperature information output device 1, the first range of the resistance of the resistor element 70 is Z o 0.50 ×ZT 0.28 Above Z o 0.50 ×Z T 0.71 Below. o ” is the combined impedance of the element unit 50 and the element unit 60 when the temperature sensing element 51 is separated from the element unit 50. In the magnet temperature information output device 1, it can be understood that the second range of the resistance is Z o 0.50 ×Z T 0.38 Above Z o 0.50 ×Z T 0.63 In the magnet temperature information output device 1, it can be understood that the first resistance of the resistor element 70 is Z o 0.50 ×Z T 0.50 .

[0082] The temperature T is set based on, for example, the temperature range of the permanent magnet 25 when the rotary electric machine MT is used. In the present embodiment, the temperature range of the permanent magnet 25 is 120° C. to 170° C., and the temperature T is set to T=150° C. Therefore, in the present embodiment, the range of the resistance of the resistor element 70 may be set to Z o 0.50 ×Z 150 0.28 Above Z o 0.50 ×Z 150 0.71 That is, in this embodiment, the resistor element 70 may also have Z o 0.50 ×Z 150 0.28 Above Z o 0.50 ×Z 150 0.71 Alternatively, the resistor element 70 may have a Z o 0.50 ×Z 150 0.38 Above Z o 0.50 ×Z 150 0.63 The following resistors.

[0083] Synthetic impedance Z T You can also use the synthetic impedance Z1 obtained in the equivalent circuit EC1 T The synthetic impedance Z TIn the embodiment, the measured value of the combined impedance of the element unit 50 and the element unit 60 when the coil 53 and the coil 61 are magnetically coupled and the temperature of the temperature sensing element 51 is T°C may be used. 150 You can also use the synthetic impedance Z1 obtained in the equivalent circuit EC1 150 The synthetic impedance Z 150 In the embodiment, the measured value of the combined impedance of the element unit 50 and the element unit 60 when the coil 53 and the coil 61 are magnetically coupled and the temperature of the temperature sensing element 51 is 150° C. can also be used. Similarly, the combined impedance Z o The combined impedance Z2 obtained in the equivalent circuit EC2 can also be used. o In the embodiment, the actually measured value of the combined impedance of the element unit 50 and the element unit 60 when the coil 53 and the coil 61 are magnetically coupled and the temperature sensing element 51 is separated from the element unit 50 may be used.

[0084] The measured value of the combined impedance of the element unit 50 and the element unit 60 when the coil 53 and the coil 61 are magnetically coupled and the temperature of the temperature sensing element 51 is T°C is measured, for example, as follows. First, the relative position of the element unit 50 and the element unit 60 is maintained in a state where the coil 53 and the coil 61 are magnetically coupled. Next, the temperature sensing element 51 is heated to T°C. In the case of measuring the above-mentioned measured value when the temperature of the temperature sensing element 51 is 150°C, the temperature sensing element 51 is heated to 150°C. Next, the combined impedance of the element unit 50 and the element unit 60 is measured. In addition, during the measurement, the resistance element 70 and the output unit 80 electrically connected to the element unit 60 may also be separated.

[0085] The measured value of the combined impedance of the element unit 50 and the element unit 60 when the coil 53 and the coil 61 are magnetically coupled and the temperature sensing element 51 is separated from the element unit 50 is measured, for example, as follows. First, the relative position of the element unit 50 and the element unit 60 is maintained in the state where the coil 53 and the coil 61 are magnetically coupled. Then, the temperature sensing element 51 is separated from the element unit 50. Then, the combined impedance of the element unit 50 and the element unit 60 is measured. In addition, during the measurement, the resistance element 70 and the output unit 80 electrically connected to the element unit 60 may also be separated.

[0086] Next, refer to Figure 5 , the configuration of the permanent magnet 25, the temperature sensing element 51 and the coil 53 will be described in more detail. Figure 5 It is a diagram showing a cross-sectional structure of a rotor core.

[0087] The rotor core 23 includes a pair of end faces 23a, 23b and a side face. The end face 23a is located near the element unit 60. That is, the end face 23a is located near the coil 61. The end face 23b is located on the opposite side of the end face 23a in the rotation axis direction D. That is, the pair of end faces 23a, 23b are perpendicular to the rotation axis direction D and face opposite directions to each other.

[0088] “A pair of end faces 23a, 23b are perpendicular to the rotation axis direction D” does not necessarily mean that the pair of end faces 23a, 23b are perpendicular to the rotation axis direction D. The pair of end faces 23a, 23b are perpendicular to the rotation axis direction D, including a slight difference within a predetermined range, a manufacturing error, or a measurement error contained in the angle formed by the pair of end faces 23a, 23b and the rotation axis direction D. When the slight difference within a predetermined range is contained in the angle formed by the pair of end faces 23a, 23b and the rotation axis direction D, the pair of end faces 23a, 23b are perpendicular to the rotation axis direction D, for example, including the angle formed within the range of ±1 degree from the vertical.

[0089] The rotor core 23 is as follows Figure 5 As shown, the rotor core 23 is composed of a plurality of steel plates M1 stacked in the rotation axis direction D. The rotor core 23 includes a plurality of steel plates M1 stacked in the rotation axis direction D. The steel plates M1 have magnetic properties. The steel plates M1 include, for example, silicon steel plates. In the present embodiment, the steel plate M1 located closest to the coil 61 among the plurality of steel plates M1 includes an end surface 23a as its surface.

[0090] The permanent magnets 25 are arranged on the rotor core 23. Figure 5 As shown, the permanent magnet 25 is integrally arranged in the rotor core 23. The permanent magnet 25 includes a pair of faces 25a, 25b and four side faces. The face 25a is located near the coil 61. The face 25b is located on the opposite side of the face 25a in the rotation axis direction D. That is, the pair of faces 25a, 25b are perpendicular to the rotation axis direction D and face opposite directions to each other. "The pair of faces 25a, 25b are perpendicular to the rotation axis direction D" does not necessarily mean that the pair of faces 25a, 25b are perpendicular to the rotation axis direction D. The pair of faces 25a, 25b are perpendicular to the rotation axis direction D, including a slight difference within a predetermined range, a manufacturing error, or a measurement error within the angle formed by the pair of faces 25a, 25b and the rotation axis direction D. In the case where the slight difference within a predetermined range is included in the angle formed by the pair of faces 25a, 25b and the rotation axis direction D, the pair of faces 25a, 25b are perpendicular to the rotation axis direction D, for example, including the angle formed within the range of ±2 degrees from the vertical.

[0091] The temperature sensing element 51 is arranged to be in contact with the permanent magnet 25. The temperature sensing element 51 is arranged on the surface 25a of the permanent magnet 25. In the present embodiment, the temperature sensing element 51 is in contact with the surface 25a of the permanent magnet 25. In the present embodiment, the temperature sensing element 51 is also arranged in its entirety in the rotor core 23, similarly to the permanent magnet 25.

[0092] The coil 53 is also arranged in the rotor core 23 in the same manner as the permanent magnet 25. In the present embodiment, at least a portion of the coil 53 is arranged in the rotor core 23. The coil 53 is arranged in the rotor core 23 at a position closer to the end surface 23a than the permanent magnet 25. One end 53a of the coil 53 in the direction D of the rotation axis is exposed from the rotor core 23. One end 53a is exposed at the end surface 23a of the rotor core 23. In the present embodiment, only one end 53a of the coil 53 is exposed from the rotor core 23, and the remaining portion of the coil 53 is buried in the rotor core 23. As Figure 5 As shown, in the present embodiment, the end face 23a is coplanar with the one end 53a of the coil 53. “The end face 23a is coplanar with the one end 53a” also includes a step of, for example, 1% or less of the length in the direction D of the rotation axis of the rotor 20 between the end face 23a and the one end 53a. The coil 53 only needs to be at least partially disposed in the rotor core 23, and the portion other than the one end 53a is exposed from the rotor core 23. In this case, for example, a portion of the side portion of the coil 53 that is located near the one end 53a may be exposed from the rotor core 23, and the end face 23a may not be coplanar with the one end 53a.

[0093] As described above, the magnet temperature information output device 1 includes the resistor element 70 electrically connected to the element unit 60. The coil 61 included in the element unit 60 is magnetically coupled to the coil 53, and therefore, power is supplied to the coil 53. Since the resistance of the temperature sensing element 51 electrically connected to the coil 53 changes according to the temperature of the permanent magnet 25, the current flowing through the coil 61 changes according to the change in the resistance of the temperature sensing element 51. The magnitude of the voltage drop generated in the resistor element 70 also changes due to the change in the current flowing through the coil 61. The output unit 80 outputs an electrical signal corresponding to the magnitude of the voltage drop generated in the resistor element 70. Therefore, the electrical signal output from the output unit 80 changes according to the temperature of the permanent magnet 25. That is, in the magnet temperature information output device 1, the temperature information related to the temperature of the permanent magnet 25 is output from the output unit 80 as an electrical signal related to the voltage. As described above, the magnet temperature information output device 1 outputs the temperature information related to the temperature of the permanent magnet 25 as an electrical signal related to the voltage.

[0094] Since the rotating electrical machine MT is provided with the magnet temperature information output device 1 described above, temperature information related to the temperature of the permanent magnet 25 is output as an electrical signal related to voltage.

[0095] Since the control circuit 41 functioning as the magnet temperature acquisition device includes the magnet temperature information output device 1, the temperature of the permanent magnet 25 is obtained based on the electric signal related to the voltage.

[0096] In the magnet temperature information output device 1, the resistor element 70 has Z o 0.50 ×Z 150 0.28 Above Z o 0.50 ×Z 150 0.71 The following resistors.

[0097] As mentioned above, Z o 0.50 ×Z 150 0.28 Above Z o 0.50 ×Z 150 0.71 The following resistance is the range of resistance of the resistance element 70 that can accurately detect the change in the temperature of the permanent magnet 25. Therefore, the magnet temperature information output device 1 outputs the temperature information related to the temperature of the permanent magnet 25 with high accuracy.

[0098] The magnet temperature information output device 1 includes a capacitor 63 which is provided on the stator 10 and forms an LC resonance circuit with the coil 61 .

[0099] The magnet temperature information output device 1 detects the change in the resistance of the temperature sensing element 51 with high accuracy. Therefore, the magnet temperature information output device 1 outputs the temperature information related to the temperature of the permanent magnet 25 with high accuracy.

[0100] In the rotary electric machine MT, the coil 53 and the coil 61 are arranged so as to face each other in the rotation axis direction D of the rotor 20 when the rotor 20 is at a predetermined rotation angle position.

[0101] In the rotary electric machine MT, the magnetic flux generated in the stator coil 11 is unlikely to affect the coil 53 and the coil 61 .

[0102] In the case of outputting the temperature information related to the temperature of the permanent magnet 25, it is considered that the resistance element 70 is not provided on the stator 10, but an electric signal related to the current flowing through the coil 61 is output as the above-mentioned temperature information output. In this structure, when the electric signal related to the above-mentioned current is obtained and the temperature of the permanent magnet 25 is obtained based on the electric signal, it is necessary to convert the electric signal related to the obtained current into an electric signal related to the voltage in the magnet temperature acquisition device. On the other hand, because the magnet temperature information output device 1 includes the resistance element 70, the electric signal related to the voltage is output as the temperature information related to the temperature of the permanent magnet 25. Therefore, in the control circuit 41 that functions as the magnet temperature acquisition device, it is not necessary to convert the electric signal related to the current into the electric signal related to the voltage. As described above, the magnet temperature information output device 1 outputs the above-mentioned temperature information that can easily obtain the temperature of the permanent magnet 25.

[0103] Next, refer to Figure 6 , Figure 7 and Figure 8 , the structure of a modified example of the magnet temperature information output device 1 is described. Figure 6 This is a circuit diagram showing another example of the magnet temperature information output device. Figure 7 and Figure 8 1 is a circuit diagram showing an equivalent circuit used when setting the resistance of a resistor element. In this modification, the structure of the element unit 50 is different from that of the above-mentioned embodiment. The following mainly describes the differences between the above-mentioned embodiment and this modification.

[0104] In this variation, if Figure 6 As shown, the element unit 50 includes a capacitor 55 in addition to the temperature sensing element 51 and the coil 53. The capacitor 55 and the coil 53 form an LC resonant circuit. The capacitor 55 may also form an LC resonant circuit with the coil 53 and the coil 61. The capacitor 55 is inserted, for example, in a manner of being connected in parallel with the coil 53. The capacitance component of the capacitor 55 may be equal to the capacitance component of the capacitor 63, or may be different from the capacitance component of the capacitor 63. In the case where the capacitance component of the capacitor 55 and the capacitance component of the capacitor 63 are different from each other, the capacitance component of the capacitor 55 may be 30% to 200% of the capacitance component of the capacitor 63, or may be 70% to 130% of the capacitance component of the capacitor 63. For example, the capacitor 55 may have a capacitance component of 100nF or less, or may have a capacitance component of 1nF to 100nF or less. The capacitance component of the capacitor 55 is not limited to the above range. The capacitance component of the capacitor 55 may be less than 1nF or greater than 100nF.

[0105] As described above, a magnetic flux corresponding to the applied AC voltage is generated in the coil 61. When the rotor 20 rotates and the coil 61 and the coil 53 approach each other, the coil 61 excites the coil 53. In this modification, a voltage having a frequency lower than a predetermined resonant frequency for exciting the coil 53 is applied to the coil 61. As described above, the predetermined resonant frequency is, for example, a resonant frequency of a circuit in the magnet temperature information output device 1 that is equivalent to the magnetic coupling between the coil 53 and the coil 61 and the temperature of the temperature sensing element 51 is a predetermined temperature. In this modification, the circuit is a circuit including the temperature sensing element 51, the coil 53, the coil 61, the capacitor 55, and the capacitor 63. Hereinafter, "the resonant frequency of the circuit in the magnet temperature information output device 1 that is equivalent to the magnetic coupling between the coil 53 and the coil 61 and the temperature of the temperature sensing element 51 is a predetermined temperature" may be referred to as a reference resonant frequency. In this modification, the difference between the frequency of the voltage applied to the coil 61 and the predetermined resonant frequency is 5 kHz or more and 30 kHz or less.

[0106] In this modification, when obtaining the combined impedance Z T , Z 0 You can also use Figure 7 The equivalent circuit EC3 and Figure 8 The equivalent circuit EC4 is shown.

[0107] The equivalent circuit EC3 is a circuit equivalent to the circuit including the temperature sensing element 51, the coil 53, the capacitor 55, the coil 61, and the capacitor 63 in the magnet temperature information output device 1 having the above-mentioned structure in the element unit 50. Therefore, the equivalent circuit EC3 includes elements corresponding to the temperature sensing element 51, the coil 53, the capacitor 55, the coil 61, and the capacitor 63. In this modification, Figure 7 As shown, the equivalent circuit EC3 includes the element R1, the element L1, R2, the element C2, the element L2, the element L3, R3, and the element C1. The element C2 corresponds to the capacitor 55. In this modification, the element C2 includes an element corresponding to the capacitance component of the capacitor 55.

[0108] In the equivalent circuit EC3, the element R3 is also connected in series with the element L3. The element C1 is connected in parallel with the element L3. The element C2 is connected in parallel with the element L1. In the equivalent circuit EC3, the end near the element C1 is untied. In the equivalent circuit EC3, the part composed of the elements R1, R2, L1 and C2 corresponds to the element unit 50, and the part composed of the elements L3, R3 and C1 corresponds to the element unit 60.

[0109] The equivalent circuit EC4 is a circuit equivalently representing a circuit in which the temperature sensing element 51 is separated from a circuit including the temperature sensing element 51, the coil 53, the capacitor 55, the coil 61, and the capacitor 63 in the magnet temperature information output device 1 in which the element unit 50 includes the temperature sensing element 51, the coil 53, and the capacitor 55. In the equivalent circuit EC4, the element R1 corresponding to the temperature sensing element 51 included in the equivalent circuit EC3 is eliminated.

[0110] In this modification, the synthetic impedance Z T You can also use the synthetic impedance Z3 obtained in the equivalent circuit EC3 T . Synthetic impedance Z3 T It is the combined impedance of the element unit 50 and the element unit 60 in the equivalent circuit EC3 when the temperature of the element R1 is T°C. The combined impedance Z 150 You can also use the synthetic impedance Z3 obtained in the equivalent circuit EC3 150 Similarly, the synthetic impedance Z o The combined impedance Z4 obtained in the equivalent circuit EC4 may be used. The combined impedance Z4 is the combined impedance of the element unit 50 and the element unit 60 in the equivalent circuit EC4.

[0111] In this modification, as described above, the synthetic impedance Z T The synthetic impedance Z3 can be used T , the synthetic impedance Z o The synthetic impedance Z4 may also be used. Therefore, in this modification, the synthetic impedance Z3 may also be used. T The first range of resistance, the second range of resistance, and the first resistance of the resistor element 70 are set by using the combined impedance Z4.

[0112] In this modification, the element unit 50 includes a capacitor 55. In this case, the magnet temperature information output device 1 detects the change in resistance of the temperature sensing element 51 with high accuracy. Therefore, the magnet temperature information output device 1 outputs temperature information related to the temperature of the permanent magnet 25 with high accuracy.

[0113] When the capacitance component of the capacitor 55 is equal to the capacitance component of the capacitor 63 , the magnet temperature information output device 1 outputs the temperature information related to the temperature of the permanent magnet 25 with high accuracy.

[0114] As described above, in this modification, the magnet temperature information output device 1 accurately outputs temperature information related to the temperature of the permanent magnet 25. The relationship between this modification and accurately outputting temperature information related to the temperature of the permanent magnet 25 will be described in more detail below.

[0115] In this modification, the magnet temperature information output device 1 more accurately detects the change in resistance of the temperature sensing element 51. For example, the structure in which the element unit 60 includes the capacitor 63 and the element unit 50 includes the capacitor 55 can detect the change in resistance of the temperature sensing element 51 more accurately than the structure in which the element unit 60 includes the capacitor 63 and the element unit 50 does not include the capacitor 55.

[0116] There are design values ​​for the inductance of coils 53 and 61 and the capacitance components of capacitors 55 and 63. However, these values ​​may deviate from the design values ​​due to manufacturing errors, for example. There are also design values ​​for the coupling constants of coils 53 and 61. However, these values ​​may deviate from the design values ​​due to, for example, deviations in the relative distance between coils 53 and 61. Deviations in the relative distance between coils 53 and 61 may be caused by, for example, installation errors when installing coils 53 and 61.

[0117] In the case of a deviation from the above-mentioned design value, the electric signal corresponding to the magnitude of the voltage drop generated in the resistor element 70, which is output as the temperature information, may be deviated. The deviation of the electric signal affects the accuracy of the temperature information. For example, the smaller the deviation of the above-mentioned electric signal, the higher the accuracy of the temperature information. On the other hand, manufacturing errors and setting errors are difficult to eliminate. Therefore, even in the case of a deviation from the above-mentioned design value due to manufacturing errors and setting errors, it is desirable to suppress the deviation of the above-mentioned electric signal.

[0118] In this modification, even if the inductance of the coils 53 and 61, the capacitance of the capacitors 55 and 63, and the coupling constant between the coils 53 and 61 deviate from the designed values, the deviation of the electric signal can be suppressed. In this modification, for example, the deviation of the electric signal can be suppressed within the temperature range of the permanent magnet 25 when the rotating electrical machine MT is used.

[0119] As described above, when the element unit 60 includes the capacitor 63 and the element unit 50 includes the capacitor 55 , the magnet temperature information output device 1 outputs the temperature information related to the temperature of the permanent magnet 25 with high accuracy.

[0120] In this modification, a voltage having a frequency lower than the predetermined resonance frequency of the exciting coil 53 is applied to the coil 61. In this modification, an AC voltage having a frequency lower than the predetermined frequency is applied to the coil 61 as a voltage having a frequency lower than the predetermined resonance frequency of the exciting coil 53.

[0121] When a voltage having a frequency lower than a predetermined resonance frequency of the exciting coil 53 is applied to the coil 61 , the magnet temperature information output device 1 outputs temperature information related to the temperature of the permanent magnet 25 with high accuracy.

[0122] In this modification, a voltage having a frequency lower than the specified resonant frequency of the exciting coil 53 is applied to the coil 61. In this modification, an AC voltage having a frequency lower than the above-mentioned specified frequency is applied to the coil 61 as a voltage having a frequency lower than the specified resonant frequency of the exciting coil 53. The difference between the frequency and the specified resonant frequency is not less than 5 kHz and not more than 30 kHz.

[0123] In this modification, even if the coupling constant between the coil 53 and the coil 61 deviates from the design value, the deviation of the electric signal can be further suppressed. In this modification, for example, in the temperature range of the permanent magnet 25 when the rotating electrical machine MT is used, the deviation of the electric signal is further suppressed. Therefore, when a voltage having a frequency lower than the predetermined resonant frequency of the exciting coil 53 is applied to the coil 61, and the difference between the frequency and the predetermined resonant frequency is 5 kHz or more and 30 kHz or less, the magnet temperature information output device 1 outputs the temperature information related to the temperature of the permanent magnet 25 with high accuracy.

[0124] Next, refer to Fig. 9 , Fig.10 and Fig.11 , the structure of other modified examples of the magnet temperature information output device 1 will be described. Fig. 9 This is a circuit diagram showing still another example of the magnet temperature information output device. Fig.10 and Fig.11 1 is a circuit diagram showing an equivalent circuit used when setting the resistance of a resistor element. In this modification, the structure of the element unit 50 and the structure of the element unit 60 are different from those of the above-mentioned embodiment. The following mainly describes the differences between the above-mentioned embodiment and this modification.

[0125] In this variation, if Fig. 9 As shown, the element unit 50 includes not only the temperature sensing element 51 and the coil 53 , but also the capacitor 55 , while the element unit 60 does not include the capacitor 63 .

[0126] In this modification, when obtaining the combined impedance Z T , Z o You can also use Fig.10 The equivalent circuit EC5 and Fig.11 The equivalent circuit EC6 is shown.

[0127] The equivalent circuit EC5 is a circuit equivalent to the circuit including the temperature sensing element 51, the coil 53, the capacitor 55 and the coil 61 in the magnet temperature information output device 1 having the above-mentioned structure in the element unit 50 and the element unit 60. Therefore, the equivalent circuit EC5 includes elements corresponding to the temperature sensing element 51, the coil 53, the capacitor 55 and the coil 61. In this modification, Fig.10As shown, the equivalent circuit EC5 includes the element R1, the element L1, R2, the element C2, the element L2, and the elements L3, R3.

[0128] In the equivalent circuit EC5, the element R3 is also connected in series with the element L2. The element C2 is connected in parallel with the element L1. In the equivalent circuit EC5, the ends near the elements L3 and R3 are untied. In the equivalent circuit EC5, the portion composed of the elements R1, R2, L1, and C2 corresponds to the element unit 50, and the portion composed of the elements L3 and R3 corresponds to the element unit 60.

[0129] The equivalent circuit EC6 is a circuit equivalently representing a circuit in which the temperature sensing element 51 is separated from a circuit including the temperature sensing element 51, the coil 53, the capacitor 55, and the coil 61 in the magnet temperature information output device 1 having the above-described structure in the element unit 50 and the element unit 60. In the equivalent circuit EC6, the element R1 corresponding to the temperature sensing element 51 included in the equivalent circuit EC5 is eliminated.

[0130] In this modification, the synthetic impedance Z T You can also use the synthetic impedance Z5 obtained in the equivalent circuit EC5 T . Synthetic impedance Z5 T It is the combined impedance of the element unit 50 and the element unit 60 in the equivalent circuit EC5 when the temperature of the element R1 is T°C. The combined impedance Z 150 You can also use the synthetic impedance Z5 obtained in the equivalent circuit EC5 150 Similarly, the synthetic impedance Z o The combined impedance Z6 obtained in the equivalent circuit EC6 may be used. The combined impedance Z6 is the combined impedance of the element unit 50 and the element unit 60 in the equivalent circuit EC6.

[0131] In this modification, as described above, the synthetic impedance Z T You can also use the synthetic impedance Z5 T , the synthetic impedance Z o The synthetic impedance Z6 may also be used. Therefore, in this modification, the synthetic impedance Z5 may also be used. T The first range of resistance, the second range of resistance, and the first resistance of the resistor element 70 are set by using the combined impedance Z6.

[0132] In this modification, the element unit 50 also includes a capacitor 55. In this case, the magnet temperature information output device 1 detects the change in resistance of the temperature sensing element 51 with high accuracy. Therefore, the magnet temperature information output device 1 outputs temperature information related to the temperature of the permanent magnet 25 with high accuracy.

[0133] Next, refer to Fig.12The structure of a modified example of the rotary electric machine MT will be described. Fig.12 2 is a diagram showing a cross-sectional structure of a rotor core. In this modification, the structure of the rotor core 23 and the arrangement of the coils 53 are different from those in the above-mentioned embodiment. The following mainly describes the differences between the above-mentioned embodiment and this modification.

[0134] In this variation, if Fig.12 As shown, the rotor core 23 includes a plate M2 in addition to a plurality of steel plates M1. The plate M2 is conductive. The plate M2 includes, for example, stainless steel or aluminum. The plate M2 is arranged on a steel plate M1 that is located at the outermost side in the rotation axis direction D among the plurality of steel plates M1 and is located near the coil 61 when the rotor 20 is at a predetermined rotation angle. In this modification, the plate M2 includes an end face 23a as its surface. In this modification, the temperature sensing element 51 and the coil 53 are buried in the plate M2. One end 53a of the coil 53 is exposed at the end face 23a included in the plate M2. Even in this modification in which the end face 23a is included in the plate M2, the end face 23a is coplanar with the one end 53a of the coil 53. In this modification, for example, a portion of the side portion of the coil 53 that is located near the one end 53a may also be exposed from the rotor core 23. The end face 23a included in the plate M2 may not be coplanar with the one end 53a.

[0135] Next, refer to Fig.13 The structure of another modified example of the rotary electric machine MT will be described. Fig.13 2 is a diagram showing a cross-sectional structure of a rotor core. In this modification, the structure of the rotor core 23 and the arrangement of the coils 53 are also different from those in the above-mentioned embodiment. The following mainly describes the differences between the above-mentioned embodiment and this modification.

[0136] In this variation, if Fig.13 As shown, the rotor core 23 includes, in addition to a plurality of steel plates M1, a plate M2a and a plate M3 different from the plate M2a. The plate M2a is not conductive, and the plate M3 is conductive. The plate M2a is arranged on a steel plate M1 located at the outermost side in the direction D of the rotation axis and close to the coil 61 among the plurality of steel plates M1. The plate M3 is arranged on the plate M2a. Therefore, in this variant, the plate M3 is also arranged on a steel plate M1 located at the outermost side in the direction D of the rotation axis and close to the coil 61 among the plurality of steel plates M1. In this variant, the plate M3 includes an end face 23a as its surface. In this variant, the temperature sensing element 51 is buried in the plate M2a, and the coil 53 is buried in the plate M3.

[0137] One end 53a of the coil 53 is exposed at the end surface 23a included in the plate M3. Even in the present modification in which the end surface 23a is included in the plate M3, the end surface 23a is coplanar with the one end 53a of the coil 53. In the present modification, for example, a portion of the side portion of the coil 53 located near the one end 53a may be exposed from the rotor core 23. The end surface 23a included in the plate M3 may not be coplanar with the one end 53a.

[0138] As mentioned above, although embodiment of this disclosure was described, this disclosure is not necessarily limited to the said embodiment, Various changes can be made within the range which does not deviate from the summary.

[0139] In the magnet temperature information output device 1, the output unit 80 may include the resistor element 70. When the output unit 80 includes the resistor element 70, the resistor element 70 may be an internal resistor of the output unit 80. When the resistor element 70 is an internal resistor of the output unit 80, the frequency of the voltage applied to the coil 61 may be a secondary resonance frequency among the predetermined resonance frequencies of the exciting coil 53. When the resistor element 70 is an internal resistor of the output unit 80 and the frequency of the voltage applied to the coil 61 is a secondary resonance frequency among the predetermined resonance frequencies, the magnet temperature information output device 1 outputs the temperature information related to the temperature of the permanent magnet 25 with high accuracy. When the resistor element 70 is not an internal resistor of the output unit 80, the frequency of the voltage applied to the coil 61 may be a primary resonance frequency among the predetermined resonance frequencies.

[0140] In the magnet temperature information output device 1, the resistor element 70 may not have Z o 0.50 ×Z 150 0.28 Above Z o 0.50 ×Z 150 0.71 The following resistors.

[0141] The resistor element 70 has a Z o 0.50 ×Z 150 0.28 Above Z o 0.50 ×Z 150 0.71 The following resistance magnet temperature information output device 1 outputs temperature information related to the temperature of the permanent magnet with high accuracy as described above.

[0142] The magnet temperature information output device 1 does not have to include the capacitor 63 .

[0143] As described above, the magnet temperature information output device 1 including the capacitor 63 detects the change in the resistance of the temperature sensing element 51 with high accuracy.

[0144] In the rotary electric machine MT, the coil 53 and the coil 61 do not need to be arranged so as to face each other in the rotation axis direction D when the rotor 20 is at a predetermined rotation angle position.

[0145] In the rotary electric machine MT in which the coil 53 and the coil 61 are arranged to face each other in the rotation axis direction D when the rotor 20 is at a predetermined rotation angle position, as described above, the magnetic flux generated in the stator coil 11 is unlikely to affect the coil 53 and the coil 61 .

[0146] In the rotating electrical machine MT, the temperature sensing element 51 may not be arranged in contact with the surface 25 a of the permanent magnet 25 . The entire permanent magnet 25 and a part of the coil 53 may not be arranged in the rotor core 23 .

[0147] The control circuit 41 may not function as a magnet temperature acquisition device. The control circuit 41 may control the driving state of the rotating electrical machine MT based on an electrical signal corresponding to the magnitude of the voltage drop generated in the resistor element 70 input from the output unit 80. In this case, the control circuit 41 may control the driving state of the rotating electrical machine MT as follows. When the control circuit 41 determines that the temperature of the permanent magnet 25 rises to a predetermined first threshold value, the control circuit 41 controls the above-mentioned electrical signal input from the output unit 80 to reduce the driving frequency to limit the rotation speed of the rotating electrical machine MT. When the control circuit 41 determines that the temperature of the permanent magnet 25 drops to a predetermined second threshold value that is smaller than the above-mentioned first threshold value, the control circuit 41 controls the above-mentioned electrical signal input from the output unit 80 to increase the driving frequency to release the restriction on the rotation speed of the rotating electrical machine MT.

[0148] Next, refer to Fig.14 , Fig.15 and Fig.16 In order to explain how to detect the change in the temperature of the permanent magnet 25 with high accuracy within the first range of the resistance of the resistor element 70, an experiment conducted by the inventors is described. In order to explain how to detect the change in the temperature of the permanent magnet 25 with higher accuracy within the second range of the resistance of the resistor element 70, an experiment conducted by the inventors is also described. Fig.14 This is a circuit diagram showing an equivalent circuit used when obtaining the relationship between the resistance of a resistor element and the accuracy of temperature information. Fig.15 and Fig.16 This is a graph showing the relationship between the resistance of a resistor element and the accuracy of temperature information. Fig.14 The equivalent circuit EC7 and Figure 4The equivalent circuit EC2 shown was subjected to experiments under the following conditions 1 to 16.

[0149] The equivalent circuit EC7 is a circuit that equivalently represents a circuit including the temperature sensing element 51, the coil 53, the coil 61, the capacitor 63, the AC power source PS, and the resistor 70 in the magnet temperature information output device 1. Therefore, the equivalent circuit EC7 includes elements corresponding to the temperature sensing element 51, the coil 53, the coil 61, the capacitor 63, the AC power source PS, and the resistor 70.

[0150] The equivalent circuit EC7 includes the element R1, the element L1, R2, the element L2, the element L3, R3, the element C1, the power supply V, and the element R4. The power supply V corresponds to the AC power supply PS. The element R4 corresponds to the resistor element 70. In the equivalent circuit EC7, the element R4 includes an element corresponding to the resistance of the resistor element 70.

[0151] In the equivalent circuit EC7, the element L3 is electrically connected to the power supply V. A voltage is applied to the element L3 from the power supply V. In the equivalent circuit EC7, a voltage corresponding to the AC voltage applied from the AC power supply PS to the coil 61 is applied to the element L3 from the power supply V. The element R4 is inserted between the element R3 and the power supply V. In the equivalent circuit EC7, the portion composed of the element R1 and the elements R2 and L1 corresponds to the element unit 50. The portion composed of the elements L3, R3, and the element C1 corresponds to the element unit 60.

[0152] (Condition 1)

[0153] Under condition 1, the power source V is set to apply an AC voltage of 85kHz and 4.5V to the element L3. The elements R2 and R3 are set to have a resistance of 2.4Ω. The elements L1 and L3 are set to have an inductance of 160μH. The element L2 is set to have a coupling constant of 0.7. The element C1 is set to have a capacitance component of 22nF. The element R4 is set to have a resistance of 300Ω. The combined impedance Z 150 Is set to 294Ω. The combined impedance Z o is set to 2980Ω.

[0154] Under condition 1, using the synthetic impedance Z 150 And the synthetic impedance Z o The first range of resistance of the resistor element 70 is set to be 268.07Ω or more and 3087.70Ω or less. In addition, under condition 1, the second range of resistance of the resistor element 70 is 473.24Ω or more and 1959.60Ω or less. That is, under condition 1, the resistance of the element R4 is within the first range of resistance and outside the second range of resistance.

[0155] Under condition 1, the magnitude of the voltage drop generated in the element R4 when the temperature of the element R1 is T°C is calculated. Under condition 1, the magnitude of the voltage drop generated in the element R4 when the temperature of the element R1 is -40°C is calculated. The temperature T of the element R1 is set in the range of 120°C to 170°C.

[0156] Hereinafter, the magnitude of the voltage drop generated in the element R4 when the temperature of the element R1 is 120°C or higher and 170°C or lower is sometimes referred to as V(T). The magnitude of the voltage drop generated in the element R4 when the temperature of the element R4 is -40°C is sometimes referred to as V(-40). For example, the magnitude of the voltage drop generated in the element R4 when the temperature of the element R1 is 120°C is referred to as V(120).

[0157] Under condition 1, as indices representing the accuracy of temperature information, indices A1, A2, and A3 are calculated. Under condition 1, as indices representing the relative accuracy of temperature information, indices A4, A5, and A6 are calculated. Indicator A1 is represented by the relational expression A1=V(120)-V(-40). Indicator A2 is represented by the relational expression A2=V(150)-V(-40). Indicator A3 is represented by the relational expression A3=V(170)-V(-40). Indicator A4 is represented by the relational expression A4={V(120)-V(-40)} / Vmax. Indicator A5 is represented by the relational expression A5={V(150)-V(-40)} / Vmax. Indicator A6 is represented by the relational expression A6={V(170)-V(-40)} / Vmax. Here, Vmax represents the maximum value of V(T) within the range of 120°C to 170°C.

[0158] (Condition 2)

[0159] Under condition 2, except that element R4 is set to an element having a resistance of 500Ω, indices A1, A2, A3 and indices A4, A5, A6 are calculated in the same manner as condition 1. Under condition 2, element R4 has a resistance within the first range of resistances and within the second range of resistances.

[0160] (Condition 3)

[0161] Under condition 3, except that element R4 is set to an element having a resistance of 1000Ω, indices A1, A2, A3 and indices A4, A5, A6 are calculated in the same manner as condition 1. Under condition 3, element R4 has a resistance within the first range of resistances and within the second range of resistances.

[0162] (Condition 4)

[0163] Under condition 4, except that element R4 is set to an element having a resistance of 2000Ω, indices A1, A2, A3 and indices A4, A5, A6 are calculated in the same manner as condition 1. Under condition 4, element R4 has a resistance within the first range of resistances and within the second range of resistances.

[0164] (Condition 5)

[0165] Under condition 5, except that element R4 is set to an element having a resistance of 3000Ω, indexes A1, A2, A3 and indexes A4, A5, A6 are calculated in the same manner as condition 1. Under condition 5, element R4 has a resistance within the first range of resistance and outside the second range of resistance.

[0166] (Condition 6)

[0167] Under condition 6, except that element R4 is set to an element having a resistance of 100Ω, indexes A1, A2, A3 and indexes A4, A5, A6 are calculated in the same manner as condition 1. Under condition 6, element R4 has a resistance outside the first range of the resistance and outside the second range of the resistance.

[0168] (Condition 7)

[0169] Under condition 7, except that element R4 is set to an element having a resistance of 5000Ω, indexes A1, A2, A3 and indexes A4, A5, A6 are calculated in the same manner as condition 1. Under condition 7, element R4 has a resistance outside the first range of the resistance and outside the second range of the resistance.

[0170] (Condition 8)

[0171] Under condition 8, the power source V is set to apply an AC voltage of 420kHz and 5.0V to the element L3. The elements R2 and R3 are set to have a resistance of 2.4Ω. The elements L1 and L3 are set to have an inductance of 30μH. The element L2 is set to have a coupling constant of 0.5. The element C1 is set to have a capacitance component of 4.7nF. The element R4 is set to have a resistance of 400Ω. The combined impedance Z 150 Set to 148.8Ω. Synthetic impedance Z o Set to 2330Ω.

[0172] Under condition 8, using the synthetic impedance Z 150 And the synthetic impedance Z oThe first range of the resistance of the resistor element 70 is set to be greater than 317.50Ω and less than 5728.95Ω. In addition, under condition 8, the second range of the resistance of the resistor element 70 is greater than 622.18Ω and less than 3344.57Ω. That is, under condition 8, the resistance of the element R4 is within the first range of the resistance and outside the second range of the resistance.

[0173] Under condition 8, as indices indicating the accuracy of the temperature information, indices A1, A2, and A3 are calculated similarly to conditions 1 to 7. Under condition 8, as indices indicating the relative accuracy of the temperature information, indices A4, A5, and A6 are calculated.

[0174] (Condition 9)

[0175] Under condition 9, except that element R4 is set to an element having a resistance of 700Ω, indexes A1, A2, A3 and indexes A4, A5, A6 are calculated in the same manner as condition 8. Under condition 9, element R4 has a resistance within the first range of the resistance and within the second range of the resistance.

[0176] (Condition 10)

[0177] Under condition 10, except that element R4 is set to an element having a resistance of 1000Ω, indexes A1, A2, A3 and indexes A4, A5, A6 are calculated in the same manner as condition 8. Under condition 10, element R4 has a resistance within the first range of the resistance and within the second range of the resistance.

[0178] (Condition 11)

[0179] Under condition 11, except that element R4 is set to an element having a resistance of 2000Ω, indexes A1, A2, A3 and indexes A4, A5, A6 are calculated in the same manner as condition 8. Under condition 11, element R4 has a resistance within the first range of the resistance and within the second range of the resistance.

[0180] (Condition 12)

[0181] Under condition 12, except that element R4 is set to an element having a resistance of 3000Ω, indexes A1, A2, A3 and indexes A4, A5, A6 are calculated in the same manner as condition 8. Under condition 12, element R4 has a resistance within the first range of the resistance and within the second range of the resistance.

[0182] (Condition 13)

[0183] Under condition 13, except that element R4 is set to an element having a resistance of 4000Ω, indexes A1, A2, A3 and indexes A4, A5, A6 are calculated in the same manner as condition 8. Under condition 13, element R4 has a resistance within the first range of the resistance and within the second range of the resistance.

[0184] (Condition 14)

[0185] In Condition 14, except that the element R4 is set to an element having a resistance of 5000Ω, the indexes A1, A2, A3 and the indexes A4, A5, A6 are calculated in the same manner as in Condition 8. In Condition 14, the element R4 has a resistance within the first range of the resistance and outside the second range of the resistance.

[0186] (Condition 15)

[0187] Under condition 15, except that element R4 is set to an element having a resistance of 100Ω, indexes A1, A2, A3 and indexes A4, A5, A6 are calculated in the same manner as condition 8. Under condition 15, element R4 has a resistance outside the first range of resistance and outside the second range of resistance.

[0188] (Condition 16)

[0189] In Condition 16, except that the element R4 is set to an element having a resistance of 6000Ω, the indexes A1, A2, A3 and the indexes A4, A5, A6 are calculated in the same manner as in Condition 8. In Condition 16, the element R4 has a resistance outside the first range of the resistance and outside the second range of the resistance.

[0190] The calculation results of conditions 1 to 7 are shown in Fig.15 In. Fig.15 The indices A1, A2, A3 and the indices A4, A5, A6 are shown together with the resistance of the element R4 in conditions 1 to 7. The calculation results of conditions 8 to 16 are shown in Fig.16 In. Fig.16 In the figure, together with the resistance of the element R4 in conditions 8 to 16, the indices A1, A2, A3 and the indices A4, A5, A6 are shown.

[0191] like Fig.15 and Fig.16As shown, when the resistance of the element R4 is within the first range of the resistance, under conditions 1 to 5 and conditions 8 to 14, the indexes A4, A5, and A6 are 60% or more. Therefore, it can be understood that the change in the temperature of the permanent magnet 25 is detected with high accuracy within the first range of the resistance. Furthermore, it can be understood that when the resistance of the element R4 is within the second range of the resistance, under conditions 2 to 4 and conditions 9 to 12, the indexes A4, A5, and A6 are 80% or more. Therefore, it can be understood that the change in the temperature of the permanent magnet 25 is detected with higher accuracy within the second range of the resistance.

[0192] Next, refer to Fig.17 and Fig.18 In order to explain that the magnet temperature information output device 1 outputs temperature information related to the temperature of the permanent magnet 25 with high accuracy, an experiment conducted by the present inventors is described. In the magnet temperature information output device 1 in this experiment, the element unit 60 includes the capacitor 63, and the element unit 50 includes the capacitor 55. Fig.17 and Fig.18 This is a graph showing the relationship between the voltage drop generated in a resistor element and the temperature.

[0193] The inventors used Figure 3 An equivalent circuit in which element R4 and power supply V are added to the equivalent circuit EC1 shown, and the following experiments under conditions 17 to 23 are performed. In the equivalent circuit in which element R4 and power supply V are added to the equivalent circuit EC1, power supply V is electrically connected to element L3, and element R4 is inserted between element R3 and power supply V. A voltage corresponding to the AC voltage applied from the AC power supply PS to the coil 61 is applied from the power supply V to element L3. For example, a voltage corresponding to the difference between the above-mentioned corresponding voltage and the voltage drop generated in element R4 is applied to element L3. Thus, the inventors of the present invention confirmed the relationship between the voltage drop and the temperature when the element unit 60 includes the capacitor 63 and the element unit 50 does not include the capacitor 55.

[0194] The inventors used Figure 7 An equivalent circuit in which element R4 and power supply V are added to the equivalent circuit EC3 shown, and experiments under the following conditions 24 to 32 are performed. In the equivalent circuit in which element R4 and power supply V are added to the equivalent circuit EC3, power supply V is electrically connected to element L3, and element R4 is inserted between element R3 and power supply V. A voltage corresponding to the AC voltage applied from the AC power supply PS to the coil 61 is applied from the power supply V to element L3. For example, a voltage corresponding to the difference between the above-mentioned corresponding voltage and the voltage drop generated in element R4 is applied to element L3. Thus, the inventors of the present invention have confirmed the relationship between the voltage drop and the temperature in the structure in which the element unit 60 includes the capacitor 63 and the element unit 50 includes the capacitor 55.

[0195] (Condition 17)

[0196] Under condition 17, power source V is set to apply an AC voltage having a frequency of a reference resonant frequency and a voltage of a reference voltage to element L3. Element R2 and element R3 are set to elements having a first reference resistance. Element L1 and element L3 are set to elements having a reference inductance. Element L2 is set to an element having a reference coupling constant. Element C1 is set to an element having a first reference capacitance component. Element R4 is set to an element having a second reference resistance. An AC voltage is applied from power source V to element L3 via element R4. The frequency of the AC voltage is the reference frequency. The voltage of the AC voltage is the reference voltage.

[0197] That is, a voltage corresponding to the difference between the reference voltage and the voltage drop generated in the element R4 is applied to the element L3.

[0198] The reference voltage, the first reference resistance, the reference inductance, the first reference capacitance component, and the second reference resistance are set based on the specifications of the coil 53, the coil 61, the capacitor 63, and the resistor 70, for example, which are used when the magnet temperature information output device 1 is actually used. The reference coupling constant is the coupling constant between the coil 53 and the coil 61 when the relative distance between the coil 53 and the coil 61 is 3.0 mm. Under condition 17, while changing the temperature of the element R1, an electric signal corresponding to the magnitude of the voltage drop generated in the element R4 is obtained, thereby obtaining the relationship between the electric signal and the temperature. Under condition 17, an electric signal representing the voltage across the element C1 is obtained as an electric signal corresponding to the magnitude of the voltage drop generated in the element R4.

[0199] (Condition 18)

[0200] Under condition 18, except that element L1 and element L3 were set to elements having an inductance increased by 5% of the reference inductance, the relationship between the electric signal corresponding to the magnitude of the voltage drop generated in element R4 and the temperature was obtained in the same manner as condition 17.

[0201] (Condition 19)

[0202] Under condition 19, except that element L1 and element L3 were set to elements having inductances that reduced the reference inductance by 5%, the relationship between the electric signal corresponding to the magnitude of the voltage drop generated in element R4 and the temperature was obtained in the same manner as condition 17.

[0203] (Condition 20)

[0204] Under condition 20, except that element C1 is set to have a capacitance component obtained by increasing the first reference capacitance component by 5%, the relationship between the electric signal corresponding to the magnitude of the voltage drop generated in element R4 and the temperature is obtained in the same manner as condition 17.

[0205] (Condition 21)

[0206] Under condition 21, except that element C1 is set to have a capacitance component that reduces the first reference capacitance component by 5%, the relationship between the electric signal corresponding to the magnitude of the voltage drop generated in element R4 and the temperature is obtained in the same manner as condition 17.

[0207] (Condition 22)

[0208] Under condition 22, except that element L2 is set to an element having a coupling constant obtained by increasing the reference coupling constant by 5%, the relationship between the electric signal corresponding to the magnitude of the voltage drop generated in element R4 and the temperature is obtained in the same manner as condition 17.

[0209] (Condition 23)

[0210] Under condition 23, except that element L2 was set to an element having a coupling constant that reduced the reference coupling constant by 5%, the relationship between the electric signal and the temperature corresponding to the magnitude of the voltage drop generated in element R4 was obtained in the same manner as condition 17.

[0211] (Condition 24)

[0212] Under condition 24, the power source V is set to a power source that applies an AC voltage having a frequency of a reference resonant frequency and a voltage of a reference voltage to the element L3. The elements R2 and R3 are set to elements having a first reference resistance. The elements L1 and L3 are set to elements having a reference inductance. The element L2 is set to an element having a reference coupling constant. The element C1 is set to an element having a first reference capacitance component. The element C2 is set to an element having a second reference capacitance component. The element R4 is set to an element having a second reference resistance. The second reference capacitance component is set based on the specifications of the capacitor 55 used when the magnet temperature information output device 1 is actually used, for example. An AC voltage is applied to the element L3 from the power source V via the element R4. The frequency of the AC voltage is the reference resonant frequency. The voltage of the AC voltage is the reference voltage. That is, a voltage corresponding to the difference between the reference voltage and the voltage drop generated in the element R4 is applied to the element L3. Under condition 24, an electrical signal corresponding to the magnitude of the voltage drop generated in the element R4 is obtained, and the relationship between the electrical signal and the temperature is obtained. Under Condition 24 , a signal representing the voltage across the element C1 is acquired as an electric signal corresponding to the magnitude of the voltage drop generated in the element R4 .

[0213] (Condition 25)

[0214] Under condition 25, except that element L1 and element L3 were set to elements having an inductance increased by 5% of the reference inductance, the relationship between the electric signal corresponding to the magnitude of the voltage drop generated in element R4 and the temperature was obtained in the same manner as condition 24.

[0215] (Condition 26)

[0216] Under condition 26, except that element L1 and element L3 were set to elements having inductances that reduced the reference inductance by 5%, the relationship between the electric signal corresponding to the magnitude of the voltage drop generated in element R4 and the temperature was obtained in the same manner as condition 24.

[0217] (Condition 27)

[0218] Under condition 27, except that element C1 is set to have a capacitance component increased by 5% of the first reference capacitance component, the relationship between the electric signal corresponding to the magnitude of the voltage drop generated in element R4 and the temperature is obtained in the same manner as condition 24.

[0219] (Condition 28)

[0220] Under condition 28, except that element C1 is set to have a capacitance component that reduces the first reference capacitance component by 5%, the relationship between the electric signal corresponding to the magnitude of the voltage drop generated in element R4 and the temperature is obtained in the same manner as condition 24.

[0221] (Condition 29)

[0222] Under condition 29, except that element C2 is set to have a capacitance component that increases the second reference capacitance component by 5%, the relationship between the electric signal corresponding to the magnitude of the voltage drop generated in element R4 and the temperature is obtained in the same manner as condition 24.

[0223] (Condition 30)

[0224] Under condition 30, except that element C2 is set to have a capacitance component that reduces the second reference capacitance component by 5%, the relationship between the electric signal corresponding to the magnitude of the voltage drop generated in element R4 and the temperature is obtained in the same manner as condition 24.

[0225] (Condition 31)

[0226] Under condition 31, except that element L2 is set to an element having a coupling constant obtained by increasing the reference coupling constant by 5%, the relationship between the electric signal and the temperature corresponding to the magnitude of the voltage drop generated in element R4 is obtained in the same manner as condition 24.

[0227] (Condition 32)

[0228] Under condition 32, except that element L2 was set to an element having a coupling constant that reduced the reference coupling constant by 5%, the relationship between the electric signal and the temperature corresponding to the magnitude of the voltage drop generated in element R4 was obtained in the same manner as condition 24.

[0229] The results of conditions 17 to 23 are shown in Fig.17 The results of conditions 24 to 32 are shown in Fig.18 middle. Fig.17 and 18 In the graph shown, the horizontal axis represents temperature [° C.], and the vertical axis represents voltage value [V] based on the electric signal corresponding to the magnitude of the voltage drop.

[0230] exist Fig.17 , relation G1 represents the relationship between the voltage drop and the temperature obtained under condition 17. Relation G2 represents the relationship between the voltage drop and the temperature obtained under condition 18. Relation G3 represents the relationship between the voltage drop and the temperature obtained under condition 19. Relation G4 represents the relationship between the voltage drop and the temperature obtained under condition 20. Relation G5 represents the relationship between the voltage drop and the temperature obtained under condition 21. Relation G6 represents the relationship between the voltage drop and the temperature obtained under condition 22. Relation G7 represents the relationship between the voltage drop and the temperature obtained under condition 23.

[0231] exist Fig.18 , relation G8 represents the relationship between the voltage drop and the temperature obtained under condition 24. Relation G9 represents the relationship between the voltage drop and the temperature obtained under condition 25. Relation G10 represents the relationship between the voltage drop and the temperature obtained under condition 26. Relation G11 represents the relationship between the voltage drop and the temperature obtained under condition 27. Relation G12 represents the relationship between the voltage drop and the temperature obtained under condition 28. Relation G13 represents the relationship between the voltage drop and the temperature obtained under condition 29. Relation G14 represents the relationship between the voltage drop and the temperature obtained under condition 30. Relation G15 represents the relationship between the voltage drop and the temperature obtained under condition 31. Relation G16 represents the relationship between the voltage drop and the temperature obtained under condition 32.

[0232] In the relationships G1 to G16, a greater change in the voltage value accompanying a rise in temperature indicates an improved accuracy in detecting a change in the resistance of the temperature sensing element 51. For example, in the relationship G1, the voltage value at 25°C is approximately 3.6V, and the voltage value at 150°C is approximately 2.6V. That is, in the relationship G1, the difference between the voltage value at 25°C and the voltage value at 150°C is approximately 1.0V.

[0233] In contrast, in relation G8, the voltage value at 25°C is about 3.1 V, and the voltage value at 150°C is about 1.1 V. That is, in relation G8, the difference between the voltage value at 25°C and the voltage value at 150°C is about 2.0 V. Therefore, it can be seen that in relation G8, the change in voltage value accompanying the increase in temperature is greater than in relation G1.

[0234] like Fig.17 and Fig.18As shown, it can be seen that in the relationships G9 to G16, the change in voltage value accompanying the temperature rise is also greater than that in the relationships G2 to G7. It can be seen that when the element unit 60 includes the capacitor 63 and the element unit 50 includes the capacitor 55, the change in voltage value accompanying the temperature rise is greater than that when the element unit 60 includes the capacitor 63 and the element unit 50 does not include the capacitor 55.

[0235] like Fig.17 and Fig.18 As shown, it can be seen that within the range of 100°C or more, the deviation of each of the relations G9 to G16 from the relation G8 is smaller than the deviation of each of the relations G2 to G7 from the relation G1. It can be seen from this that even if the inductance of the coils 53 and 61, the capacitance of the capacitors 55 and 63, and the coupling constant between the coils 53 and 61 deviate from the designed values, when the element unit 60 includes the capacitor 63 and the element unit 50 includes the capacitor 55, the deviation of the output electric signal amplitude can be suppressed. Therefore, when the element unit 60 includes the capacitor 63 and the element unit 50 includes the capacitor 55, the magnet temperature information output device 1 outputs the temperature information related to the temperature of the permanent magnet 25 with high accuracy.

[0236] Next, refer to Fig.19 , Fig. 20 , Fig.21 , Fig. 22 and Fig.23 In order to explain that the magnet temperature information output device 1 outputs the temperature information related to the temperature of the permanent magnet 25 with high accuracy, another experiment conducted by the inventors is described. In the other experiment, a voltage having a frequency lower than the predetermined resonant frequency of the excitation coil 53 is applied to the coil 61, and the difference between the frequency and the predetermined resonant frequency is 5 kHz or more and 30 kHz or less. Fig.19 , Fig. 20 , Fig.21 , Fig. 22 and Fig.23 is a graph showing the relationship between the voltage drop and temperature generated in a resistor element. Figure 7 The equivalent circuit EC2 shown above is an equivalent circuit in which the element R4 and the power supply V are added, and the following experiments are performed under conditions 34 to 48. As a result, the inventors confirmed the relationship between the voltage drop and the temperature when the frequency of the voltage applied to the coil 61 is lower than the above-mentioned predetermined resonant frequency and the difference between the frequency and the predetermined resonant frequency is 5 kHz to 30 kHz.

[0237] (Condition 34)

[0238] Under condition 34, power source V is set to a power source that applies an AC voltage having a frequency of a reference resonant frequency and a voltage of a reference voltage to element L3. As described above, the reference resonant frequency is an example of a prescribed resonant frequency of the excitation coil 53. Therefore, under condition 34, the prescribed resonant frequency of the excitation coil 53 is set as the frequency of the voltage applied to element L3. Element R2 and element R3 are set as elements having a first reference resistance. Element L1 and element L3 are set as elements having a reference inductance. Element L2 is set as an element having a reference coupling constant. Element C1 is set as an element having a first reference capacitance component. Element C2 is set as an element having a second reference capacitance component. Element R4 is set as an element having a second reference resistance. An AC voltage is applied to element L3 from power source V via element R4. The frequency of the AC voltage is the reference frequency. The voltage of the AC voltage is the reference voltage. That is, a voltage corresponding to the difference between the reference voltage and the voltage drop generated in element R4 is applied to element L3. Under condition 34, while changing the temperature of element R1, an electric signal corresponding to the magnitude of the voltage drop generated in element R4 is obtained, thereby obtaining the relationship between the electric signal and the temperature. Under condition 34, a signal representing the voltage across element C1 is obtained as an electric signal corresponding to the magnitude of the voltage drop generated in element R4.

[0239] (Condition 35)

[0240] Under condition 35, except that element L2 is set to an element having a first coupling constant, the relationship between the electric signal corresponding to the magnitude of the voltage drop generated in element R4 and the temperature is obtained in the same manner as in condition 34. The first coupling constant is the coupling constant between coil 53 and coil 61 when the relative distance between coil 53 and coil 61 is 2.5 mm.

[0241] (Condition 36)

[0242] Under condition 36, except that element L2 is set as an element having a second coupling constant, the relationship between the electric signal corresponding to the magnitude of the voltage drop generated in element R4 and the temperature is obtained in the same manner as in condition 34. The second coupling constant is the coupling constant between coil 53 and coil 61 when the relative distance between coil 53 and coil 61 is 3.5 mm.

[0243] (Condition 37)

[0244] Under condition 37, except that the power source V is set to a power source that applies an AC voltage having a frequency 5 kHz lower than the reference resonant frequency to the element L3, the relationship between the electric signal corresponding to the magnitude of the voltage drop generated in the element R4 and the temperature is obtained in the same manner as in condition 34. That is, under condition 37, a frequency 5 kHz lower than the prescribed resonant frequency of the excitation coil 53 is set as the frequency of the voltage applied to the element L3.

[0245] (Condition 38)

[0246] Under Condition 38, except that the element L2 is set to an element having the first coupling constant, the relationship between the electric signal corresponding to the magnitude of the voltage drop generated in the element R4 and the temperature is obtained in the same manner as Condition 37.

[0247] (Condition 39)

[0248] Under Condition 39, except that the element L2 is set to an element having the second coupling constant, the relationship between the electric signal corresponding to the magnitude of the voltage drop generated in the element R4 and the temperature is obtained in the same manner as Condition 37.

[0249] (Condition 40)

[0250] In Condition 40, except that the power source V is set to a power source that applies an AC voltage having a frequency 10 kHz lower than the reference resonant frequency to the element L3, the relationship between the electric signal corresponding to the magnitude of the voltage drop generated in the element R4 and the temperature is obtained in the same manner as in Condition 34. That is, in Condition 40, a frequency 10 kHz lower than the prescribed resonant frequency of the excitation coil 53 is set as the frequency of the voltage applied to the element L3.

[0251] (Condition 41)

[0252] Under condition 41, except that element L2 is set to an element having the first coupling constant, the relationship between the electric signal corresponding to the magnitude of the voltage drop generated in element R4 and the temperature is obtained in the same manner as condition 40.

[0253] (Condition 42)

[0254] Under condition 42, except that element L2 is set to an element having the second coupling constant, the relationship between the electric signal corresponding to the magnitude of the voltage drop generated in element R4 and the temperature is obtained in the same manner as condition 40.

[0255] (Condition 43)

[0256] Under condition 43, except that the power source V is set to a power source that applies an AC voltage having a frequency 20 kHz lower than the reference resonant frequency to the element L3, the relationship between the electric signal corresponding to the magnitude of the voltage drop generated in the element R4 and the temperature is obtained in the same manner as in condition 34. That is, under condition 43, a frequency 20 kHz lower than the prescribed resonant frequency of the excitation coil 53 is set as the frequency of the voltage applied to the element L3.

[0257] (Condition 44)

[0258] Under condition 44, except that element L2 is set to an element having the first coupling constant, the relationship between the electric signal corresponding to the magnitude of the voltage drop generated in element R4 and the temperature is obtained in the same manner as condition 43.

[0259] (Condition 45)

[0260] Under condition 45, except that element L2 is set to an element having the second coupling constant, the relationship between the electric signal corresponding to the magnitude of the voltage drop generated in element R4 and the temperature is obtained in the same manner as condition 43.

[0261] (Condition 46)

[0262] In condition 46, except that the power source V is set to a power source for applying an AC voltage having a frequency 30 kHz lower than the reference resonant frequency to the element L3, the relationship between the electric signal corresponding to the magnitude of the voltage drop generated in the element R4 and the temperature is obtained in the same manner as in condition 34. That is, in condition 46, a frequency 30 kHz lower than the prescribed resonant frequency of the excitation coil 53 is set as the frequency of the voltage applied to the element L3.

[0263] (Condition 47)

[0264] Under condition 47, except that element L2 is set to an element having the first coupling constant, the relationship between the electric signal corresponding to the magnitude of the voltage drop generated in element R4 and the temperature is obtained in the same manner as condition 46.

[0265] (Condition 48)

[0266] Under condition 48, except that element L2 is set to an element having the second coupling constant, the relationship between the electric signal corresponding to the magnitude of the voltage drop generated in element R4 and the temperature is obtained in the same manner as condition 46.

[0267] The results of conditions 34 to 36 are shown in Fig.19 The results of conditions 37 to 39 are shown in Fig. 20 The results of conditions 40 to 42 are shown in Fig.21 The results of conditions 43 to 45 are shown in Fig. 22 The results of conditions 46 to 48 are shown in Fig.23 middle. Figure 19 to Figure 23 In the graph shown, the horizontal axis represents temperature [° C.], and the vertical axis represents voltage value [V] based on the electric signal corresponding to the magnitude of the voltage drop.

[0268] exist Fig.19 In FIG. 1 , relation G17 represents the relation between the voltage drop and the temperature obtained under condition 34. Relation G18 represents the relation between the voltage drop and the temperature obtained under condition 35. Relation G19 represents the relation between the voltage drop and the temperature obtained under condition 36.

[0269] exist Fig. 20 In FIG. 1 , relation G20 represents the relation between the voltage drop and the temperature obtained under condition 37. Relation G21 represents the relation between the voltage drop and the temperature obtained under condition 38. Relation G22 represents the relation between the voltage drop and the temperature obtained under condition 39.

[0270] exist Fig.21 In FIG. 4 , relation G23 represents the relation between the voltage drop and the temperature obtained under condition 40. Relation G24 represents the relation between the voltage drop and the temperature obtained under condition 41. Relation G25 represents the relation between the voltage drop and the temperature obtained under condition 42.

[0271] exist Fig. 22 In FIG. 4 , relation G26 represents the relation between the voltage drop and the temperature obtained under condition 43. Relation G27 represents the relation between the voltage drop and the temperature obtained under condition 44. Relation G28 represents the relation between the voltage drop and the temperature obtained under condition 45.

[0272] exist Fig.23 In FIG. 4 , relation G29 represents the relation between the voltage drop and the temperature obtained under condition 46. Relation G30 represents the relation between the voltage drop and the temperature obtained under condition 47. Relation G31 represents the relation between the voltage drop and the temperature obtained under condition 48.

[0273] like Fig.19 and Fig. 20 As shown, it can be seen that within the range of 100°C to 180°C, the deviation of each of relations G21 and G22 relative to relation G20 is smaller than the deviation of each of relations G18 and G19 relative to relation G17. In relations G20 to G22, especially near 120°C, the deviation of each of relations G21 and G22 relative to relation G20 is suppressed. It can be seen that even if the coupling constant of coil 53 and coil 61 deviates from the design value, when the frequency of the voltage applied to coil 61 is 5 kHz lower than the specified resonant frequency of exciting coil 53, the deviation of the output electrical signal amplitude can be suppressed within the range of 100°C to 180°C.

[0274] like Fig.19 and Fig.21As shown, it can be seen that within the range of 100°C to 180°C, the deviation of each of relations G24 and G25 from relation G23 is smaller than the deviation of each of relations G18 and G19 from relation G17. In particular, it can be seen that within the range of 120°C to 180°C, the deviation of each of relations G24 and G25 from relation G23 is smaller than the deviation of each of relations G18 and G19 from relation G17. In relations G23 to G25, especially around 130°C, the deviation of each of relations G24 and G25 from relation G23 is suppressed. It can be seen that even if the coupling constant of coil 53 and coil 61 deviates from the design value, when the frequency of the voltage applied to coil 61 is 10 kHz lower than the specified resonant frequency of exciting coil 53, the deviation of the output electric signal amplitude can be suppressed within the range of 100°C to 180°C.

[0275] like Fig.19 and Fig. 22 As shown, it can be seen that within the range of 100°C to 180°C, the deviation of each of relations G27 and G28 from relation G26 is smaller than the deviation of each of relations G18 and G19 from relation G17. In particular, within the range of 130°C to 180°C, the deviation of each of relations G27 and G28 from relation G26 is smaller than the deviation of each of relations G18 and G19 from relation G17. In relations G26 to G28, especially around 150°C, the deviation of each of relations G27 and G28 from relation G26 is suppressed. It can be seen that even if the coupling constant of coil 53 and coil 61 deviates from the design value, when the frequency of the voltage applied to coil 61 is 20 kHz lower than the specified resonant frequency of exciting coil 53, the deviation of the output electric signal amplitude can be suppressed within the range of 100°C to 180°C.

[0276] like Fig.19 and Fig.23 As shown, it can be seen that within the range of 100°C to 180°C, the deviation of each of the relations G30 and G31 from the relation G29 is smaller than the deviation of each of the relations G18 and G19 from the relation G17. In particular, it can be seen that within the range of 140°C to 180°C, the deviation of each of the relations G30 and G31 from the relation G29 is smaller than the deviation of each of the relations G18 and G19 from the relation G17. In the relations G29 to G31, especially around 170°C, the deviation of each of the relations G30 and G31 from the relation G29 is suppressed. It can be seen that even if the coupling constant of the coil 53 and the coil 61 deviates from the design value, when the frequency of the voltage applied to the coil 61 is 30 kHz lower than the specified resonant frequency of the exciting coil 53, the deviation of the output electric signal amplitude can be suppressed within the range of 100°C to 180°C.

[0277] It can be seen from this that even if the coupling constant between the coil 53 and the coil 61 deviates from the design value, when the frequency of the voltage applied to the coil 61 is lower than the predetermined resonant frequency of the exciting coil 53, and the difference between the frequency and the predetermined resonant frequency is 5 kHz or more and 30 kHz or less, the deviation of the output electric signal amplitude can be suppressed. Therefore, when the frequency of the voltage applied to the coil 61 is lower than the predetermined resonant frequency of the exciting coil 53, and the difference between the frequency and the predetermined resonant frequency is 5 kHz or more and 30 kHz or less, the magnet temperature information output device 1 outputs the temperature information related to the temperature of the permanent magnet 25 with high accuracy.

Claims

1. A device for outputting magnet temperature information, wherein: The magnet temperature information output device is provided in a rotating electrical machine having a stator and a rotor provided with a permanent magnet, and the magnet temperature information output device outputs temperature information related to the temperature of the permanent magnet. The magnet temperature information output device comprises: A first element unit, which is disposed on the rotor and includes: a temperature sensing element whose resistance changes according to the temperature of the permanent magnet, and a first coil electrically connected to the temperature sensing element; A second element unit, which is disposed on the stator and includes a second coil magnetically coupled to the first coil; a resistance element electrically connected to the second element unit; and an output unit electrically connected to the second element unit and the resistance element, The output unit outputs an electrical signal corresponding to the magnitude of a voltage drop generated in the resistance element as the temperature information.

2. The magnet temperature information output device according to claim 1, wherein: The resistance element has Z o 0.50 ×Z 150 0.28 Above Z o 0.50 ×Z 150 0.71 The following resistors, Here, Z 150 is the combined impedance of the first element unit and the second element unit when the first coil and the second coil are magnetically coupled and the temperature of the temperature sensing element is 150° C., Z o The impedance is the combined impedance of the first element unit and the second element unit in a state where the first coil and the second coil are magnetically coupled and the temperature sensing element is separated from the first element unit.

3. The magnet temperature information output device according to claim 1 or 2, wherein: The second element unit further includes a capacitor that forms an LC resonance circuit with the second coil.

4. The magnet temperature information output device according to any one of claims 1 to 3, wherein: The first element unit further includes a capacitor that forms an LC resonance circuit with the first coil.

5. The magnet temperature information output device according to claim 1 or 2, wherein: The first element unit further includes a capacitor forming an LC resonant circuit with the first coil, The second element unit further includes a capacitor that forms an LC resonance circuit with the second coil.

6. The magnet temperature information output device according to claim 5, wherein: A voltage having a frequency lower than a predetermined resonance frequency for exciting the first coil is applied to the second coil.

7. The magnet temperature information output device according to claim 6, wherein: The difference between the frequency and the predetermined resonant frequency is not less than 5 kHz and not more than 30 kHz. 8 . A rotating electrical machine comprising the magnet temperature information output device according to claim 1 .

9. The rotating electrical machine according to claim 8, wherein: The first coil and the second coil are arranged to face each other in a rotation axis direction of the rotor when the rotor is at a predetermined rotation angle position.

10. The rotating electrical machine according to claim 8 or 9, wherein: The rotor comprises a rotor core, The entire permanent magnet and at least a portion of the first coil are disposed in the rotor core. The permanent magnet includes a pair of faces perpendicular to the direction of the rotation axis of the rotor. The temperature sensing element is arranged so as to be in contact with a surface of the pair of surfaces that is located close to the second coil when the rotor is at a predetermined rotation angle position.

11. The rotating electrical machine according to claim 10, wherein: The rotor core includes a pair of end faces perpendicular to the rotation axis direction of the rotor. Of the pair of end faces, an end face located closer to the second coil is coplanar with one end of the first coil in the direction of the rotation axis of the rotor.

12. The rotating electrical machine according to claim 10 or 11, wherein: The rotor core includes a plurality of steel plates and sheets stacked along the rotation axis direction, The plurality of steel plates have magnetic properties, The plate has electrical conductivity and is disposed on a steel plate located at the outermost position in the direction of the rotation axis of the rotor and close to the second coil among the plurality of steel plates. The first coil is buried in the board.

13. A device for obtaining magnet temperature, wherein: The magnet temperature acquisition device comprises a magnet temperature information output device as described in any one of claims 1 to 7, The electric signal output from the magnet temperature information output device is acquired, and the temperature of the permanent magnet is obtained based on the acquired electric signal.

14. A temperature information output device, wherein: The temperature information output device is provided in a rotating electrical machine including a stator and a rotor provided with a permanent magnet, and outputs temperature information related to a temperature of a portion in the rotor. The temperature information output device comprises: A first element unit, which is disposed on the rotor and includes: a temperature sensing element whose resistance changes according to the temperature of the portion, and a first coil electrically connected to the temperature sensing element; A second element unit, which is disposed on the stator and includes a second coil magnetically coupled to the first coil; a resistance element electrically connected to the second element unit; and an output unit electrically connected to the second element unit and the resistance element, The output unit outputs an electrical signal corresponding to the magnitude of a voltage drop generated in the resistance element as the temperature information.

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