JP5091905B2 - Motor structure with resolver - Google Patents

Description

  The present invention includes a casing in which a motor stator and a bearing are fixed, a rotating shaft having a motor rotor rotatably supported by the bearing, and a resolver stator of a resolver for detecting a rotation angle of the motor rotor. The present invention relates to a resolver-equipped motor structure in which a rotor is attached to a motor rotor.

  Conventionally, high output brushless motors are used in hybrid vehicles and electric vehicles. In order to control a brushless motor of a hybrid vehicle, it is necessary to accurately grasp the rotational position of the output shaft of the motor. This is because it is necessary to accurately grasp the rotational position of the rotor in order to control energization switching to each coil of the stator. In particular, in an automobile, since cogging deteriorates drivability, it is desired to reduce cogging. Therefore, there is a strong demand for accurately switching energization.

Here, a resolver is used for detecting the position of the motor shaft of an automobile in order to satisfy functions such as high temperature resistance, noise resistance, vibration resistance, and high humidity resistance. The resolver is incorporated in the motor and is directly attached in series to the rotor shaft of the motor.
FIG. 24 is a cross-sectional view of a resolver-equipped motor 200 disclosed in Patent Document 1. A motor stator 202 is fixed to the inner periphery of the casing 208. A bus bar 201 is attached to one end of the motor stator 202, and a resolver stator 203 is fixed to the inner peripheral end surface of the bus bar 201. The resolver stator 203 includes a wound resolver stator coil 204.

In addition, a pair of bearings 209 is fixed to the casing 208, and the rotation shaft 205 of the motor rotor 206 is rotatably supported by the pair of bearings 209. A resolver rotor 207 is fixed to the rotary shaft 205 at a position facing the resolver stator 203. The resolver stator 203 and the resolver rotor 207 constitute a resolver.
Patent Document 2 also describes the same invention as Patent Document 1. The difference between the invention of Patent Document 2 and the invention of Patent Document 1 is that in Patent Document 1, the resolver stator 203 is attached to the bus bar 201, whereas in Patent Document 2, the resolver stator is fixed to the casing. It has been done.

  On the other hand, the invention of Patent Document 3 discloses an invention in which the number of turns of the coil of the resolver stator is reduced and the cost is reduced by using an excitation signal modulated with a high frequency. According to the present invention, since the number of turns can be reduced, it is disclosed that a sheet-like coil can be used without using a winding coil, and the resolver can be made compact.

JP 2007-124757 A Japanese Unexamined Patent Publication No. 09-065617 JP 2000-292205 A

However, the conventional resolver-equipped motor structure has the following problems.
(1) In the motor structure with resolver of Patent Document 1 and Patent Document 2, when the resolver rotor 207 is opposed to the resolver stator 203 around which the resolver stator coil 204 is wound, it has substantially the same width. The axial length becomes longer. Therefore, there is a problem that the entire motor becomes large in the axial direction of the rotation shaft.
(2) Since excitation is performed in the frequency range of 8 to 10 kHz, disturbance electromagnetic noise from the motor (motor rotation speed 18000 rpm, NS pole 4 pairs, in the case of a 6th-order motor, a frequency of 7.2 kHz) The magnetic field generated by the motor stator 202 gives a large noise to the resolver stator coil 204 because it has an iron core (back core). For this reason, there is a problem in that the resolver angle detection accuracy is lowered.
In the inventions of Patent Documents 1 and 2, in order to reduce the influence of noise, a resolver must be installed at a position away from the motor stator, and there is a problem that the length in the axial direction becomes long.

(3) In the motor structure with a resolver of Patent Document 3, the cost can be reduced by reducing the number of turns. However, since the motor has a back core, the magnetic field generated by the motor stator is generated in the back core. Since it passes easily and gives noise to the sheet-like coil of the resolver stator, there is a problem in that the accuracy of resolver angle detection is lowered.
(4) Further, when the resolver receives a disturbance magnetic field having a high magnetic flux density, if the iron core is magnetically saturated, the resolver cannot function at all.

  Accordingly, the present invention has been made to solve the above-described problems, and can reduce the length of the rotation axis of the motor in the axial direction and improve the angle detection accuracy by the resolver. An object is to provide a motor structure with a resolver.

The resolver-equipped motor structure according to the present invention made to solve the above problems has the following configuration.
(1) A casing having a motor stator and a bearing fixed thereto, a rotating shaft having a motor rotor rotatably supported by the bearing, and a resolver stator of a resolver for detecting a rotation angle of the motor rotor are attached to the casing. In the motor structure with a resolver in which a resolver rotor is attached to the motor rotor, the resolver rotor is configured by an air core coil, and is provided on an end surface of the motor rotor, and the resolver stator is configured by an air core coil. It is characterized by having.
(2) In the motor structure with a resolver described in (1), a nonmagnetic flat plate is provided between the resolver rotor and an end surface of the motor rotor.

(3) In the motor structure with a resolver described in (1) or (2), the air-core coil is formed of a conductive ink.
(4) In the motor structure with a resolver described in (3), the air-core coil includes a SIN coil layer in which a through hole is formed, a first insulating layer, a jumper wire layer, and a second insulating layer. A structure in which a COS coil layer is laminated, and the conductive ink on the upper layer of each layer is connected to the conductive ink on the lower layer through the through hole. It is characterized by.
(5) In any one of the motor structures with a resolver described in (1) to (4), a signal of 300 kHz to 500 kHz or a signal of 1.8 MHz to 2.7 MHz as the excitation signal of the resolver stator. It is characterized by using.

Next, the operation and effect of the rotation detector-equipped motor structure of the present invention having the above configuration will be described.
(1) A casing having a motor stator and a bearing fixed thereto, a rotating shaft having a motor rotor rotatably supported by the bearing, and a resolver stator of a resolver for detecting a rotation angle of the motor rotor are attached to the casing. In the motor structure with a resolver in which a resolver rotor is attached to the motor rotor, the resolver rotor is configured by an air core coil, and is provided on an end surface of the motor rotor, and the resolver stator is configured by an air core coil. By eliminating the back core, the magnetic field generated by the motor stator does not affect the resolver stator via the back core, and is affected by the resolver stator, for example. However, the maximum motor noise is about 7.2kHz. Ri, resolver signal so 500 kHz, the noise can be easily removed using a high-pass filter, not decrease the resolver angle detection accuracy. Here, the reason why the back core can be eliminated is that excitation is performed at a high frequency of 500 kHz, so that the degree of coupling is increased and the signal can be sufficiently transmitted without the back core.
Further, even when the resolver receives a disturbance magnetic field having a high magnetic flux density, since there is no iron core, the iron core is not magnetically saturated, and the resolver can always function normally.
In addition, since the high frequency is used, the number of turns of the resolver stator can be reduced to several turns, so that it is not easily affected by noise of 100 kHz or less.
In addition, since the thin-film resolver stator and the resolver rotor are arranged to face each other in the axial direction of the rotation shaft, the length occupied by the resolver in the axial direction of the rotation shaft can be shortened.

(2) Since it has a nonmagnetic flat plate between the resolver rotor and the end face of the motor rotor, the magnetic flux generated in the motor stator generates eddy currents on the surface of the nonmagnetic flat plate and generates heat. Therefore, the magnetic flux reaching the resolver stator can be reduced, the noise received by the resolver stator from the motor stator can be reduced, and the resolver angle detection accuracy is not lowered. Furthermore, since the shield member is a copper plate or copper plating, sufficient shielding can be performed against the lines of magnetic force.
(3) Since the air-core coil is formed of conductive ink, it can be formed with high accuracy, and a thin film pattern with an accurate width can be formed. Accuracy can be improved.
Furthermore, since the thin film pattern is fixed to the resolver rotor member by applying an ink liquid in which silver particles are dispersed in a dispersant and then firing the ink liquid, the thin film pattern is securely attached to the resolver rotor member. Can be fixed to. The air-core coil is not limited to a thin film, and may be formed by etching a copper foil.

(4) The air-core coil has a structure in which a SIN coil layer, a first insulating layer, a jumper wire layer, a second insulating layer, and a COS coil layer each having a through hole are laminated. The conductive ink of the layer on the upper side of each layer is connected to the conductive ink of the lower layer through a through hole. Since the resolver stator can be efficiently manufactured simply by forming the air-core coil, the manufacturing cost can be reduced.

(5) Further, as an excitation signal of the resolver stator, a signal of 300 kHz or more and 500 kHz or less, or a signal of 1.8 MHz or more and 2.7 MHz or less is used. Therefore, in an automobile, AM radio (531 kHz to 1602 kHz ) And short-wave radio (2 MHz to 26 MHz), it rarely gives radio noise. That is, the AM radio is used in an area of 500 kHz or higher, so that an excitation signal of 500 kHz or less rarely gives noise to the radio. At 500 kHz, the S / N ratio is sufficiently large in the resolver of the present invention. At 300 kHz, the S / N ratio decreases to about ½ of the S / N ratio of 500 kHz, but this is a practical range.
In addition, since an excitation signal of 300 kHz or higher is used, motor noise of about 10 kHz can be easily cut by a high-pass filter, so that the angle detection accuracy of the resolver can be increased.

It is sectional drawing which shows the structure of the motor which concerns on 1st Embodiment and incorporates a resolver. Similarly, it is a plan view of a resolver stator 77. Similarly, it is the A section enlarged view of FIG. Similarly, it is the B section enlarged view of FIG. Similarly, a base coat 103 is formed on the base plate 102. Similarly, it is a figure which shows the structure of the SIN signal exciting coil 91. FIG. Similarly, it is a view showing an insulating coat 110. Similarly, it is a figure showing jumper lines 128 and 129. Similarly, it is a view showing an insulating coat 120. Similarly, it is a figure which shows the structure of the COS signal exciting coil 92. FIG. Similarly, it is a figure which applies a terminal part adhesive. Similarly, it is a diagram showing a protective film 131. Similarly, it is a cross-sectional schematic diagram showing the configuration of each layer. Similarly, it is a figure which shows the control structure of a resolver. Similarly, it is a figure which shows the structure of the resolver rotor 93. FIG. Similarly, it is a figure which shows the amount of disturbance magnetic flux in a real vehicle. Similarly, it is a data figure which shows the influence on the detection angle of disturbance magnetic flux. Similarly, it is a data figure which shows the influence which disturbance magnetic flux exerts on a resolver. It is sectional drawing which shows the structure of the motor which concerns on 2nd Example and incorporates a resolver. Similarly, it is a plan view of a resolver rotor member 19. Similarly, it is a figure which shows the resolver stator 1st pattern 51. FIG. Similarly, it is a figure which shows the resolver stator 2nd pattern 52. FIG. Similarly, it is a figure which shows the control structure of a resolver. It is sectional drawing which shows the structure of the conventional motor incorporating a resolver.

A first embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a sectional view simply showing the structure of the motor of the first embodiment.
The motor 10 is a brushless motor including a case main body 79, a case cover 71, a motor stator 72, a motor rotor 73, a motor shaft 74, and motor bearings 76a and 76b.
The case main body 79 and the case cover 71 are made by casting aluminum alloy or the like. The case main body 79 is fitted with a motor bearing 76b. The case cover 71 is fitted with a motor bearing 76a. It is pivotally supported.

A motor stator 72 is fixed to the inner periphery of the case main body 79. The motor stator 72 includes a coil and generates a magnetic force when energized.
On the other hand, a motor rotor 73 having a permanent magnet is fixed to the motor shaft 74. The motor stator 72 and the motor rotor 73 are held at a predetermined distance. When the motor stator 72 is energized, the motor rotor 73 rotates and generates a driving force to transmit power to the motor shaft 74.
A resolver rotor 75 is fixed to the end surface of the motor rotor 73 via a nonmagnetic and conductive shield plate 78. The shield plate 78, which is a non-magnetic flat plate, uses a copper plate in this embodiment, but may be made of brass or aluminum.
A resolver stator 77 is fixed to the case cover 71. With the case main body 79 and the case cover 71 assembled, the resolver rotor 75 and the resolver stator 77 are arranged apart from each other by a predetermined distance. The closer the predetermined distance is, the better the detection accuracy of the resolver 80 can be. However, the predetermined distance is determined in consideration of dimensional tolerance, dimensional change due to temperature, and the like.

FIG. 14 is a block diagram showing resolver position detection control.
The resolver 80 includes a circuit 88 configured by 2X and a sensor unit 89. The circuit 88 includes a SIN signal generator 81, a carrier wave generator 82, a COS signal generator 83, a first modulator 84, a second modulator 85, a detector 86, and a phase difference detector 87. The sensor unit 89 includes a SIN signal excitation coil 91, a COS signal excitation coil 92, a detection coil 93, a rotor side rotary transformer 94, and a stator side rotary transformer 95.
A SIN signal generator 81 for generating a 7.2 kHz SIN signal wave is connected to the first modulator 84 as shown in FIG. A COS signal generator 83 that generates a 7.2 kHz COS signal wave is connected to the second modulator 85.
A carrier wave generator 82 for generating a 500 kHz carrier wave is connected to the first modulator 84 and the second modulator 85. The SIN signal generator 81 and the COS signal generator 83 are connected to a phase difference detector 87. The detector 86 is connected to the phase difference detector 87.
The first modulator 84 is connected to the SIN signal excitation coil 91, and the second modulator 85 is connected to the COS signal excitation coil 92.
The detection coil 93 is connected to the rotor-side rotary transformer 94, and the stator-side rotary transformer 95 is connected to the detector 86.

Next, the structure of the SIN signal exciting coil 91 and the COS signal exciting coil 92 will be described in detail.
FIG. 2 is a plan view showing the structure of the resolver stator 77. FIG. 13 is a schematic cross-sectional view showing the structure of the resolver stator 77. As shown in FIG. 13, the resolver stator 77 has a SIN signal excitation coil 91, an insulation coat 110, jumper wires 128 and 129, an insulation coat 120, and a COS signal on a base plate 102 having a base coat 103 formed on the surface. An exciting coil 92 and an insulating overcoat 131 are sequentially laminated. Hereinafter, each layer will be described.
The base plate 102 is a donut-shaped flat plate made of PPS resin. On the outer periphery of the base plate 102, a convex portion 102a including a connection terminal is formed.
FIG. 5 shows a state in which the base coat 103 is formed on the upper surface of the base plate 102. The base coat 103 is not formed on the upper surface of the convex portion 102a. The base coat 103 is for smoothing the surface of the base plate 102.

FIG. 6 shows a case where a SIN signal exciting coil 91 is applied to the upper surface of the base coat 103 by an ink jet printer. In the SIN signal exciting coil 91, four sets of SIN signal exciting coils 91A, 91B, 91C, 91D are arranged at positions shifted by 90 degrees in electrical angle. The number of turns of each coil is 7 turns. The four sets of SIN signal exciting coils 91A, 91B, 91C, 91D have inner peripheral ends 104A, 104B, 104C, 104D on the inner peripheral side, and outer peripheral ends 105A, 105B, 105C, 105D on the outer peripheral side. doing. Each coil circulates sequentially from the inner peripheral end 104 with a slight gap toward the outer periphery, forming seven turns, and reaches the outer peripheral end 105.
One end of the SIN signal exciting coil 91 </ b> A is connected to the external terminal 109. One end of the SIN signal exciting coil 91B is connected to the external terminal 108.
In addition, a transformer 95A constituting a part of the stator-side rotary transformer 95 is applied to the inner peripheral side of the SIN signal exciting coil 91 by an ink jet printer. One end of the transformer 95A is connected to the external terminal 106. The other end of the transformer 95A is connected to the transformer end 107.

FIG. 7 shows a plan view of the insulating coat 110 coated on the SIN signal exciting coil 91. In the insulating coat 110, through holes 111A, 111B, 111C, and 111D are formed at positions corresponding to the inner peripheral end portions 104A, 104B, 104C, and 104D. Further, through holes 112A, 112B, 112C, and 112D are formed at positions corresponding to the outer peripheral end portions 105A, 105B, 105C, and 105D.
In addition, a through hole 113 is formed in the insulating coat 110 at a position corresponding to the transformer end 107. The insulating coat 110 has a notch 110 a at a position corresponding to the external terminal 106. A wiring method using a through hole will be described later.

FIG. 8 shows a case where jumper wires 128 and 129 are applied to the upper surface of the insulating coat 110 by an ink jet printer. The jumper line 128 is a jumper line for the SIN signal excitation coil 91, and the jumper line 129 is a jumper line for the COS signal excitation coil 92. The jumper lines 128 and 129 will be described in detail after the COS signal exciting coil 92 in FIG. 10 is described.
As shown in FIG. 8, a transformer 95 </ b> B constituting a part of the stator-side rotary transformer 95 is applied to the inner peripheral side of the jumper wires 128 and 129 by an ink jet printer. One end of the transformer 95B is connected to the external terminal 127. The other end of the transformer 95B is connected to the transformer end 126.
FIG. 9 is a plan view of the insulating coat 120 coated on the jumper wires 128 and 129. FIG. 10 shows a case where a COS signal exciting coil 92 is applied to the upper surface of the insulating coat 120 by an ink jet printer. In the COS signal exciting coil 92, four sets of COS signal exciting coils 92A, 92B, 92C, and 92D are arranged at positions shifted by 90 degrees in electrical angle. The number of turns of each coil is 6 turns. The COS signal excitation coils 92A, 92B, 92C, and 92D are formed with a 45-degree phase shift with respect to the SIN signal excitation coils 91A, 91B, 91C, and 91D.

The four sets of COS signal exciting coils 92A, 92B, 92C, and 92D have inner peripheral ends 115A, 115B, 115C, and 115D on the inner peripheral side, and outer peripheral ends 116A, 116B, 116C, and 116D on the outer peripheral side. doing. Each coil sequentially turns from the inner peripheral end 115 with a slight gap toward the outer periphery to form six turns and reaches the outer peripheral end 116.
One end of the COS signal exciting coil 92A is connected to the external terminal 117. One end of the SIN signal exciting coil 92D is connected to the external terminal 117.
As shown in FIG. 9, the insulating coat 120 has through holes 121A, 121B, 121C, COS signal excitation coils 92A, 92B, 92C, 92D at positions corresponding to the inner peripheral ends 115A, 115B, 115C, 115D. 121D is formed. In addition, through holes 122A, 122B, 122C, and 122D are formed at positions corresponding to the outer peripheral end portions 116A, 116B, 116C, and 116D.
In addition, the insulating coat 120 is formed with a notch 120 a at a position corresponding to the external terminals 106 and 126.

Next, a connection method using the jumper line 128 will be described. As shown in FIG. 6, the external terminal 108 is connected to one end of the SIN signal exciting coil 91B, and is connected to the inner peripheral end 104B by forming a 7-turn coil counterclockwise. The inner peripheral end portion 104B is connected to one end of the jumper line 128B through the through hole 111B. The other end of the jumper wire 128B is connected to the outer peripheral end portion 105B through the through hole 112B.
As shown in FIG. 6, the outer peripheral end portion 105B is connected to the outer end portion 105C of the SIN signal exciting coil 91C. The outer end portion 105C is connected to one end of the jumper wire 128C through the through hole 112C. The other end of the jumper line 128C is connected to the inner peripheral end portion 104C through the through hole 111C. The inner circumferential end 104C forms a 7-turn coil clockwise and is connected to one end of the SIN signal excitation coil 91D, and forms a 7-turn coil counterclockwise and connected to the inner end 104D. ing.

The inner peripheral end portion 104D is connected to one end of the jumper line 128D through the through hole 111D. The other end of the jumper line 128D is connected to the outer peripheral end portion 105D through the through hole 112D.
The outer peripheral end portion 105D is connected to the external end portion 105A of the SIN signal exciting coil 91A. The external end portion 105A is connected to one end of the jumper wire 128A through the through hole 112A. The other end of the jumper line 128A is connected to the inner peripheral end 104A through the through hole 111A. The inner peripheral end 104 </ b> A forms a seven-turn coil clockwise and is connected to the external terminal 109.

Next, a connection method using the jumper line 129 will be described. As shown in FIG. 10, the external terminal 118 is connected to one end of the COS signal excitation coil 92A, and is connected to the inner peripheral end 115A by forming a 7-turn coil counterclockwise. As shown in FIGS. 8 and 9, the inner peripheral end 115A is connected to one end of the jumper wire 129A through the through hole 121A. The other end of the jumper wire 129A is connected to the outer peripheral end portion 116A through the through hole 122A.
As shown in FIG. 10, the outer peripheral end portion 116A is connected to the external end portion 116B of the COS signal exciting coil 92B. The external end portion 116B is connected to one end of the jumper wire 129B through the through hole 122B. The other end of the jumper wire 129B is connected to the inner peripheral end 115B through the through hole 121B. The inner peripheral end portion 115B forms a 7-turn coil clockwise and is connected to one end of the COS signal exciting coil 92C, and forms a 7-turn coil counterclockwise and connected to the inner end 115C. ing.

The inner peripheral end 115C is connected to one end of the jumper line 129C through the through hole 121C. The other end of the jumper wire 129C is connected to the outer peripheral end portion 116C through the through hole 122C.
The outer peripheral end portion 116C is connected to the external end portion 116D of the COS signal exciting coil 92D. The external end portion 116D is connected to one end of the jumper wire 129D through the through hole 122D. The other end of the jumper line 129D is connected to the inner peripheral end 115D through the through hole 121D. The inner peripheral end 115D forms a seven-turn coil clockwise, goes around the outer periphery of the COS signal exciting coil 92A, and is connected to the external terminal 117.

Next, a method for connecting the rotary transformer 95 will be described.
As shown in FIG. 6, with the external terminal 106 as one end, the other end 107 of the rotary transformer 95A formed in a circle is connected to one end of the rotary transformer 95B in FIG. ing. The other end of the rotary transformer 95B is connected to the external terminal 126.
Next, as shown in FIG. 11, a conductive adhesive is applied to the terminal portion to form an external terminal, which is connected to an external line. 3 and 4 show a state in which the external terminals 106, 126, 108, 109, 117, and 118 are formed by applying a conductive adhesive.
FIG. 3 shows a connection structure between the external terminals 106 and 126 and the rotary transformers 95A and 95B. (B) is the A section enlarged view of FIG. 2, (a) is sectional drawing of (b).
FIG. 4 shows a connection structure of the external terminals 117. (A) is the B section enlarged view of FIG. 2, (b) is sectional drawing of (a).
Next, as shown in FIG. 12, the protective film 131 is formed by overcoating the entire surface including the convex portion 102a.

Next, the resolver rotor 75 in which the detection coil 93 is formed will be described. FIG. 15 is an exploded perspective view showing the configuration of the resolver rotor 75. (E) shows the base plate 161 of the resolver rotor 75. (D) shows the first coil layer 162 formed on the surface of the base plate 161. (C) shows an interlayer insulating layer 163 for insulating the first coil layer 162 and the second coil layer 164. FIG. 6B shows the second coil layer 164 formed on the interlayer insulating layer 163. (A) shows the overcoat 165 which is an insulating resin and is a protective film.
As shown in (e), the base plate 161 has a disk shape with a circular hole in the center, and is formed in a recess of the plate 161a made of a nonmagnetic conductive metal such as aluminum or brass and having a recess formed on the surface. A resin such as PPS is filled and solidified.

  The first coil layer 162 includes four detection coils 162a, 162b, 162c, and 162d. The second coil layer 164 also includes four detection coils 164a, 164b, 164c, and 164d. One end of each of the detection coils 162a, 162b, 162c, and 162d is connected to one end of the rotary transformer 166. The other ends of the detection coils 162a, 162b, 162c, and 162d are connected to one ends of the four detection coils 164a, 164b, 164c, and 164d of the second coil layer 164 through the through holes 163a. The other ends of the detection coils 164a, 164b, 164c, 164d are connected to one end of the rotary transformer 167. The other end of the rotary transformer 166 and the other end of the rotary transformer 167 are connected through a through hole.

As a result, when an induction current is generated in the detection coils 162 and 164 in response to the magnetic flux generated in the excitation coil, a current flows through the rotary transformers 166 and 167.
Due to the magnetic flux generated by the induced current, an induced current is generated in the rotary transformer 95 on the resolver body side. By analyzing this induced current, the rotational position of the resolver rotor can be calculated.
According to the present embodiment, since the rotary transformer 166 is formed on the first coil layer 162 and the rotary transformer 167 is formed on the second coil layer 164, the area occupied by the rotary transformer in one coil layer. Therefore, the outer dimension of the resolver can be reduced.

Next, the effect by the resolver structure of a present Example is demonstrated. FIG. 16 shows the intensity of the magnetic flux generated from the motor stator and the disturbance magnetic flux for the resolver in the hybrid vehicle. The vertical axis represents the amount of magnetic flux (unit mT), and the horizontal axis represents the condition. In steady state (100 km / h), it is about 7 mT. In the intermediate acceleration state where acceleration is performed from 60 km / h to 100 km / h, the speed is about 24 mT. In the zero start acceleration state in which acceleration is performed from 0 km / h to 50 km / h, the speed is about 32 mT / h.
FIG. 17 shows the amount of change in the detected angle of the resolver when 39 mT is given as the disturbance magnetic flux. The vertical axis represents the change in detection angle, and the horizontal axis represents the electrical angle. H is the data of the resolver of the present invention, and J is the data of the conventional resolver. In the conventional resolver structure, detection angle changes (errors) occur at all electrical angles. In contrast, according to the resolver structure of the present invention, almost no electrical angle change (error) occurs in almost all electrical angles.
FIG. 18 shows the influence of the resolver when the disturbance magnetic flux is changed. The vertical axis represents detection angle change (error), and the horizontal axis represents disturbance magnetic flux (mT). H is the data of the resolver of the present invention, and J is the data of the conventional resolver. In the conventional resolver, when the disturbance magnetic flux increases, the detection angle change (error) also increases in proportion. According to the resolver of the present invention, even if the disturbance magnetic flux increases, the detection angle change (error) hardly increases.

  Next, the operation of the resolver having the above configuration will be described. The SIN signal excitation coil 91 of the resolver stator 77 is excited with a sine curve (Asin ωt) that is the first excitation signal S1 that is amplitude-modulated by a 500 kHz carrier wave. Further, the COS signal excitation coil 92 is excited with a cosine curve that is a second excitation signal that is amplitude-modulated by a carrier wave of 500 kHz, so that ABsin (ωt + θ) that is an output signal is induced in the resolver rotor pattern 94. Occurs as. The output signal is input to the phase detector 87 via the rotary transformer patterns 94 and 95 and the detector 86 provided on the stator side. On the other hand, a sin curve (Asin ωt) as a first excitation signal is input from the drive circuit 81 to the phase detector 87. The position calculator 87 calculates the rotation angle of the motor rotor 73 from the deviation of the zero cross detection timing in the phase detector 87.

  As described above in detail, according to the resolver structure of the present embodiment, the casings 71 and 79 in which the motor stator 72 and the bearings 76a and 76b are fixed, and the motor rotor that is rotatably supported by the bearings 76a and 76b. In a motor structure with a resolver in which a resolver stator 77 of a resolver is attached to the casing 10 and a resolver rotor 75 is attached to the motor rotor 73 in order to detect a rotation angle of the motor rotor 73, a resolver rotor 75 is provided. Since it is configured by an air-core coil and is provided on the end surface of the motor rotor 73 and the resolver stator 77 is configured by an air-core coil, the motor stator 72 is formed by eliminating the back core. The generated disturbance magnetic flux is transmitted to the resolver stator 77 through the back core. Without giving the sound, the resolver stator 77 it is possible to reduce noise received from the motor stator 72, it is not reduced the resolver angle detection accuracy. Here, the back core can be eliminated because excitation is performed at a high frequency of 500 kHz, and even a minute signal can be sufficiently detected.

Further, even when the resolver receives a disturbance magnetic field having a high magnetic flux density, since there is no iron core, the iron core is not magnetically saturated, and the resolver can always function normally.
Further, since the high frequency is used, the number of turns of the resolver stator 77 can be reduced to several turns (7 turns in the present embodiment), so that it is not easily affected by noise of 100 kHz or less. In this embodiment, the SIN signal exciting coil 91 and the COS signal exciting coil 92 are configured with 7 turns, but may be configured with 4 to 7 turns according to the number of rotations of the motor and the number of magnetic poles.
Further, since the resolver of the present embodiment is less affected by noise from the motor, a thin film resolver stator 77 and a resolver rotor 75 are arranged to face each other in the axial direction of the rotation shaft. In addition, the length occupied by the resolver in the axial direction of the rotating shaft can be shortened, and the motor can be downsized.

Further, since the shield plate 78, which is a nonmagnetic and conductive flat plate, is provided between the resolver rotor 75 and the end surface of the motor rotor 73, the magnetic flux generated in the motor stator 72 is generated by the base plate 102 or Since eddy current is generated on the surface of the shield plate 78 and converted into heat, the magnetic flux reaching the resolver stator 77 can be reduced, and the noise received by the resolver stator 77 from the motor stator 72 can be reduced. The angle detection accuracy is not lowered.
In addition, since the air-core coil is formed of conductive ink, the thin film pattern can be accurately formed with a thickness of 10 μm or less, and a thin film pattern with an accurate width can be formed. Therefore, the resolver accuracy can be improved.
Furthermore, since the thin film pattern is fixed to the resolver rotor member by applying an ink liquid in which silver particles are dispersed in a dispersant and then firing the ink liquid, the thin film pattern is securely attached to the resolver rotor member. Can be fixed to.

The air-core coil includes a SIN signal exciting coil 91 in which through holes are formed, an insulating coat 110 as a first insulating layer, a layer in which jumper wires 128 and 129 are formed, and a second insulating layer. It has a structure in which a certain insulating coat 120 and a COS signal exciting coil 92 are laminated, and the conductive ink of the layer on the upper side of each layer passes through the through holes 111, 112, 121, 122 of the layer on the lower side. Since it is connected to conductive ink, the resolver stator 77 can be efficiently manufactured simply by forming each layer and forming an air-core coil by inkjet, thus reducing the manufacturing cost. it can.
Further, as the excitation signal of the resolver stator, a signal of 300 kHz to 500 kHz or a signal of 1.8 MHz to 2.7 MHz is used. Gives less radio noise. Since the radio is used in an area of 500 kHz or more, an excitation signal of 500 kHz or less rarely gives noise to the radio. At 500 kHz, the S / N ratio is sufficiently large in the resolver of the present invention. At 300 kHz, the S / N ratio decreases to about ½ of the S / N ratio of 500 kHz, but this is a practical range.
Further, since an excitation signal of 300 kHz or higher is used, motor noise of about 10 kHz at the maximum can be easily cut by the bypass filter, so that the angle detection accuracy of the resolver can be increased. Further, since the number of turns is reduced so that the resolver is coupled at a high frequency, it is difficult to couple a noise signal of 100 kHz or less.

[Second Embodiment]
Hereinafter, a most preferred first embodiment in which the motor structure with a rotation detector of the present invention is embodied will be described in detail with reference to the drawings.
FIG. 19 is a sectional view showing the structure of a motor incorporating a resolver as a rotation detector according to this embodiment. The outer casing is constituted by a motor casing 11 and a lid casing 20. A motor stator 12 is fixed inside the motor casing 11. A bearing 21 is attached to the motor casing 11. The bearing 21 is also attached to the inside of the lid casing 20, and the motor shaft 13 is rotatably held by the pair of bearings 21.

A motor rotor 15 is attached to the motor shaft 13 via a guide 14, and a permanent magnet 16 is built and fixed in the motor rotor 15. The left end surface of the motor rotor 15 is in contact with the guide 14. A shield plate 18 is attached in contact with the right end surface of the motor rotor 15. The shield plate 18 is a copper plate. A resolver rotor member 19 is attached to the right side of the shield plate 18. The resolver rotor member 19 will be described later in detail.
The motor shaft 13 is formed with a step portion 13a having a smaller diameter than the diameter with which the guide 14 is fitted. Further, on the right side of the stepped portion 13a, a small diameter stepped portion 13b having a diameter smaller than the diameter of the stepped portion 13a is formed. A stopper 17 is fitted to the step portion 13a. A crimping portion 17 a is formed at the right end of the stopper 17. The small diameter step portion 13 b is in contact with the side surface of the inner ring of the bearing 21 through the spacer 22.

The guide 14 is fitted and mounted on the motor rotor 13, and the motor rotor 15 is fitted and mounted on the guide 14. Next, in a state where the shield plate 18 and the resolver rotor member 19 are fitted and mounted on the outer periphery of the caulking portion 17a of the stopper 17, the caulking portion 17a of the stopper 17 is directed outward with a caulking tool (not shown). Thereby, the guide 14, the motor rotor 15, the shield plate 18, and the resolver rotor member 19 are fixed to the motor shaft 13.
At this time, since the caulking tool caulks the caulking portion 17a evenly, the resolver rotor member 19 can be attached to the axis of the motor shaft 13 with high accuracy.
On the other hand, a resolver stator member 23 is positioned and fixed on the inner surface of the lid casing 20. The resolver stator member 23 will be described later in detail.

Next, the resolver rotor member 19 will be described. FIG. 20 shows a plan view of the resolver rotor member 19.
The resolver rotor member 19 has a disk shape in which a circular center hole is formed at the center. The diameter is 100 to 150 mm. The material of the resolver rotor member 19 is PPS resin or LCP liquid crystal polymer, and the thickness is 3 to 5 mm.
On one surface of the resolver rotor member 19, resolver rotor patterns 30A, 30B, 30C, and 30D are formed at four locations. A rotary transformer pattern 31 is formed near the center. The resolver rotor pattern 30 and the rotary transformer pattern 31 are formed by an ink jet printer. As the ink, a silver paste in which silver particles are dispersed in a dispersant is used. After the silver paste is applied with a thickness of 10 to 20 μm, it is fired. By firing, the dispersant sublimes, and a silver thin film having a thickness of 2 to 5 μm is fixed to the surface. The width of the resolver rotor pattern 30 is 0.5 mm.
An insulating layer made of polyimide having a thickness of 10 μm is formed on the surfaces of the resolver rotor pattern 30 and the rotary transformer pattern 31. This insulating layer is also fired after applying polyimide.

The four resolver rotor patterns 30 are each formed in a loop shape in a section divided by 90 degrees. After the four resolver patterns 30 are formed, an insulating layer made of polyimide is formed by baking except for the vicinity of the terminal portions of each pattern. On the insulating layer, connection lines (connection lines for connecting 37A and 37B in the figure) for connecting one end 34 of the resolver pattern 30A and one end of the resolver rotor pattern 30B are formed. This connection line is formed by an ink jet printer.
Further, one end 34 of the resolver pattern 30A is connected to one end 36 of the rotary transformer pattern 31 through a similar connection line. The other end of the resolver rotor pattern 30B is connected to one end of the resolver rotor pattern 30C through a similar connection line. The other end of the resolver rotor pattern 30C is connected to one end of the resolver rotor pattern 30D via a connection line (a connection line connecting 37C and 37D in the figure). The other end 34 of the resolver pattern 30D is connected to the other end 35 of the rotary transformer pattern 31 through a similar connection line.
Thereafter, an insulating layer made of polyimide is formed by baking on the connection line and the terminal portion. As a result, the sum of the induced currents generated in the four resolver rotor patterns 30A, 30B, 30C, and 30D flows to the rotary transformer pattern 31 due to the change in the magnetic field.
In the present embodiment, the connection is made by providing a multi-layer connection line on the same surface, but the connection may be made using the back surface using a through hole.

Next, the resolver stator member 23 will be described. The resolver stator member 23 has a disk shape in which a circular center hole is formed at the center. The diameter is 100 to 150 mm. The material of the resolver stator member 23 is PPS resin or LCP liquid crystal polymer, and the thickness is 3 to 5 mm.
The resolver stator member 23 is fitted and adhered to the inner surface of the lid casing 20 inside a positioning projection 20a formed as a circumferential projection. Thereby, the resolver stator member 23 is positioned with respect to the shaft center of the motor shaft 13 via the bearing 21.
In this embodiment, the distance between the resolver rotor pattern 30 on the surface of the resolver rotor member 19 and the resolver stator second pattern 52 on the surface of the resolver stator member 23 is set to about 1.5 mm.

As shown in FIG. 21, resolver stator first patterns 51A, 51B, 51C, and 51D are formed on one surface of the resolver stator member 23 at four locations. A rotary transformer pattern 57 is formed near the center.
Further, a polyimide insulating layer having a thickness of 10 μm is formed on the surfaces of the first resolver stator pattern 51 and the rotary transformer pattern 57. This insulating layer is also fired after applying polyimide. Then, the resolver stator second pattern 52 of FIG. 22 which is 90 degrees out of phase with the resolver stator first pattern 51 is formed on the surface of the insulating layer so as to overlap.
The resolver stator first pattern 51, the rotary transformer pattern 57, and the resolver stator second pattern 52 are formed by an ink jet printer. As the ink, a silver paste in which silver particles are dispersed in a dispersant is used. After the silver paste is applied with a thickness of 10 to 20 μm, it is fired. By firing, the dispersant sublimes, and a silver thin film having a thickness of 2 to 5 μm is fixed to the surface. The width of the resolver rotor pattern 30 is 0.5 mm.

An insulating layer made of polyimide having a thickness of 10 μm is formed on the surface of the resolver stator second pattern 52. This insulating layer is also fired after applying polyimide.
The four resolver stator first patterns 51A, 51B, 51C, 51D are connected by the connection lines described in FIG. The resolver stator first pattern 51 is formed with a pair of input terminals 53. The input terminal 53 is connected to the drive circuit 56 as shown in FIG. FIG. 23 is a diagram illustrating a control configuration of the resolver.
Further, the four resolver stator second patterns 52A, 52B, 52C, and 52D are connected by the connection lines described in FIG. A pair of input terminals 53 are formed on the resolver stator second pattern 52. The input terminal 53 is connected to the drive circuit 56 as shown in FIG.

Next, the control configuration will be described. As shown in FIG. 23, the drive circuit 56 for generating the 7.2 kHz sin curve (Asin ωt) as the first excitation signal and the 7.2 kHz cos curve (Acos ωt) as the second excitation signal includes the resolver stator first. The first pattern 51 and the resolver stator second pattern 52 are connected. The resolver stator first pattern 51 is supplied with a sin curve from the drive circuit 56, and the resolver stator second pattern 52 is supplied with a cosine curve from the drive circuit 56. The sin curve and the cos curve have the same amplitude and are 90 degrees out of phase.
In the resolver rotor pattern 30, the output signal ABsin (ωt + θ) is generated as an induced current. The output signal is input to the comparator 54 provided on the stator side via the rotary transformer patterns 31 and 57. On the other hand, a sin curve (Asinωt) is input from the drive circuit 56 to the comparator 55.

In order to avoid erroneous detection due to noise, the position calculator 58 uses a dead band that does not respond to noise as a hysteresis voltage, and a predetermined hysteresis voltage is input to the comparator 54 that detects zero crossing.
Similarly, in the comparator 55, in order to avoid erroneous detection due to noise, the position calculator 58 inputs a dead band that does not respond to noise to the comparator 55 that detects a zero cross.

  Next, the operation of the resolver having the above configuration will be described. The resolver stator first pattern 51 is excited with a sin curve (Asin ωt) as a first excitation signal S1, and the resolver stator second pattern 52 is excited with a cosine curve as a second excitation signal, whereby a resolver rotor pattern. 30, ABsin (ωt + θ), which is the output signal S2, is generated as an induced current. The output signal S2 is input to the comparator 54 provided on the stator side via the rotary transformer patterns 31 and 57. On the other hand, a sin curve (Asin ωt) that is the first excitation signal S <b> 1 is input from the drive circuit 56 to the comparator 55. The position calculator 58 calculates the rotation angle of the motor rotor 15 from the difference between the zero cross detection timing of the comparator 54 and the zero cross detection timing of the comparator 55.

As described in detail above, according to the motor structure with a resolver of the present embodiment, the resolver is fixed to the lid casing 20, and the thin-film resolver stator first pattern 51 and resolver stator second pattern 52 are formed on the surface. Since it has the disk-shaped resolver stator member 23 formed and the disk-shaped resolver rotor member 19 fixed to the end face of the motor rotor 15 and having a thin-film resolver rotor pattern 30 formed on the surface thereof, The resolver stator first pattern 51, the resolver stator second pattern 52, and the resolver rotor pattern 30 are arranged so as to face the axial direction of the motor shaft 13, so that the resolver is in the axial direction of the motor shaft 13. Occupied length can be shortened.

Further, since the resolver rotor pattern 30 is formed as a thin film pattern on the surface of the resolver rotor member 19 by an ink jet printer, the thin film pattern can be accurately formed with a thickness of 10 μm or less, and an accurate width Since a thin film pattern can be formed, the accuracy of the resolver can be improved.
Furthermore, since the resolver rotor pattern 30 is fixed to the resolver rotor member 19 by applying an ink liquid in which silver particles are dispersed in a dispersant, and then baking the ink liquid, the thin film pattern is surely formed. It can be fixed to the resolver rotor member 19.
Further, since the shield plate 18 is provided between the rotor and the resolver rotor member 19, the influence of the magnetic field by the permanent magnet 16 provided in the resolver rotor member 19 and the influence of the magnetic field that is generated in the motor stator 12 are changed. Therefore, the rotation angle can be detected with high accuracy. Furthermore, since the shield member is the copper shield plate 18 or copper plating, sufficient shielding can be performed against the lines of magnetic force.

  The present invention can be applied in various ways in addition to the above embodiments. For example, in each of the above embodiments, the shield plate 18 made of aluminum or copper is used as the shield member, but a shield plate made of brass may be used. Further, a thick copper plating may be used.

  The present invention can be used, for example, in a motor of a hybrid vehicle or an electric vehicle.

71 Motor casing 72 Motor stator 73 Motor rotor 74 Motor shaft 78 Shield plate 75 Resolver rotor 71 Cover casing 76 Bearing 77 Resolver stator 91 SIN signal excitation coil 92 COS signal excitation coil 110, 120 Insulation coating 111, 112, 121, 122 Through hole 128 129 Jumper wire 11 Motor casing 12 Motor stator 13 Motor shaft 15 Motor rotor 18 Shield plate 19 Resolver rotor member 20 Lid casing 21 Bearing 23 Resolver stator member 30 Resolver rotor pattern 31, 57 Rotary transformer pattern 51 Resolver stator first pattern 52 Resolver Stator second pattern

Claims (5)

A casing in which a motor stator and a bearing are fixed, a rotating shaft having a motor rotor rotatably supported by the bearing, and a resolver stator of a resolver for detecting a rotation angle of the motor rotor are attached to the casing, and the resolver rotor In the motor structure with a resolver attached to the motor rotor,
The resolver rotor is constituted by an air-core coil, and is provided on an end surface of the motor rotor;
The resolver stator is constituted by an air-core coil;
A motor structure with a resolver. In the motor structure with a resolver according to claim 1,
A resolver-equipped motor structure comprising a nonmagnetic flat plate between the resolver rotor and an end surface of the motor rotor. In the motor structure with a resolver according to claim 1 or claim 2,
A resolver-equipped motor structure, wherein the air-core coil is formed of conductive ink. In the motor structure with a resolver according to claim 3,
The air-core coil has a structure in which a SIN coil layer in which a through hole is formed, a first insulating layer, a jumper wire layer, a second insulating layer, and a COS coil layer are laminated;
The conductive ink of the layer on the upper side of each layer is connected to the conductive ink of the lower layer through the through-hole,
Resolver-equipped motor structure. In any one of the motor structures with a resolver described in claim 1 to claim 4,
Using a signal of 300 kHz to 500 kHz or a signal of 1.8 MHz to 2.7 MHz as the excitation signal of the resolver stator;
Resolver-equipped motor structure.

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