JP2007318856A - Control device of motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a control device which can perform the operation of a motor suitable for an actual phase difference while enabling the phase difference between an external rotor and an internal rotor to be changed according to various kinds of requirements. <P>SOLUTION: The phase difference between the external rotor 3 and the internal rotor 4 can be changed by operating the pressure P1, P2 of pressure chambers 24, 25 to which working fluids (working oil) are fed. A value of a parameter of the phase difference between both the rotors 3, 4 or a parameter of a phase difference such as an induction voltage constant Ke is estimated by detecting the pressure P1, P2, and on the basis of the detected results. A conducting current of the motor 1 is controlled according to the estimated value of the phase difference parameter. A means 30 for relatively rotating both the rotors 3, 4 operates the pressure P1, P2 of the pressure chambers 24, 25 according to operation command values P1_c, P2_c which are determined according to differences between the phase parameters and the estimated value. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a motor control device that changes a field by changing a phase difference between an outer rotor and an inner rotor each having a permanent magnet.

  2. Description of the Related Art Conventionally, in a permanent magnet type electric motor, a double rotor structure electric motor having a permanent magnet for each of two coaxially arranged rotors (an outer rotor and an inner rotor) is known (for example, see Patent Document 1). reference). In this type of electric motor, the outer rotor and the inner rotor are capable of relative rotation about their axis. By changing the phase difference between the outer rotor and the inner rotor, the total field strength generated by the permanent magnets of both rotors can be changed.

  In the electric motor found in Patent Document 1, the phase difference between the outer rotor and the inner rotor changes mechanically according to the rotational speed of the electric motor. That is, the outer rotor and the inner rotor are connected via a member that is displaced in the radial direction of the electric motor by the action of centrifugal force. And with the displacement of this member, the outer rotor rotates relative to the inner rotor, and the phase difference between the outer rotor and the inner rotor changes. In this case, when the electric motor is in a stopped state, the direction of the magnetic pole of the permanent magnet provided in the outer rotor is the same as the direction of the magnetic pole of the permanent magnet provided in the inner rotor, and is generated by those permanent magnets. The permanent magnets of each rotor are arranged so that the total field magnetic flux is maximized. As the rotational speed of the electric motor increases, the phase difference between the two rotors increases due to the centrifugal force, and the total field magnetic flux decreases (the field is weakened).

  Here, in FIG. 10, the vertical axis represents the output torque Tr of the motor, and the horizontal axis represents the number of revolutions N of the motor. In FIG. A line (a line connecting points where the phase voltage of the motor becomes equal to the power supply voltage by a combination of the rotation speed and the output torque when the motor is operated with the field constant). In the figure, X is a region that does not require field weakening, and Y is a region that requires field weakening.

  As shown in FIG. 10, the region Y in which field weakening is required depends not only on the rotational speed N of the motor but also on the output torque Tr. For this reason, as can be seen in Patent Document 1, in an electric motor configured such that the strength of the field changes only in accordance with the rotational speed of the electric motor, it is likely to cause an excess or deficiency of the field depending on the operating state. There is an inconvenience.

  In addition, the field weakening control originally reduces the counter electromotive force generated in the armature due to the rotation of the motor and suppresses the voltage between the terminals of the armature from becoming higher than the power supply voltage. It can be used in the rotation range. And in the technique of patent document 1 which changes the phase difference between an outer rotor and an inner rotor with the rotation speed and centrifugal force of an electric motor, since the parameter for operating the field strength is only the rotation speed, There is an inconvenience that the control range of the output torque and the rotational speed of the electric motor cannot be changed flexibly.

  In addition, in an electric motor that also operates as a generator, in general, the field strength for the same number of revolutions is set during driving (when the output torque is positive) and during power generation (when the output torque is negative). Changing it will increase the driving efficiency. However, the technique of Patent Document 1 that changes the phase difference between the outer rotor and the inner rotor by the rotational speed or centrifugal force has a disadvantage that the field strength cannot be changed between driving and power generation. .

Furthermore, the electric motor found in Patent Document 1 does not have means for detecting the actual phase difference between the outer rotor and the inner rotor, and thus the actual field state, on the control device side that controls energization of the electric motor. Therefore, the energization control of the motor may not match the actual field state. In such a case, the output torque of the electric motor is likely to cause an error with respect to the torque command value, and problems such as a decrease in operating efficiency of the electric motor and vibration of the electric motor are likely to occur.
JP 2002-204541 A

  The present invention has been made in view of the above background, and it is possible to change the phase difference between the outer rotor and the inner rotor according to various demands, and to provide an electric motor suitable for the actual phase difference. It is an object of the present invention to provide a control device that enables operation.

  In order to achieve the above object, an electric motor control apparatus according to the present invention includes an outer rotor having a plurality of permanent magnets arranged in the circumferential direction, and a plurality of permanent magnets arranged in the circumferential direction, An inner rotor provided coaxially with the inner rotor, and an inter-rotor relative rotation means for rotating one of the outer rotor and the inner rotor relative to the other around the axis of both rotors, the outer rotor and the inner rotor. A control device for an electric motor capable of changing a composite field of permanent magnets of both rotors by changing a phase difference between the two rotors by relative rotation between the rotors, and the relative rotation means between the rotors A first member provided integrally with the outer rotor so as to be rotatable relative to the inner rotor; a second member provided integrally with the inner rotor so as to be rotatable relative to the outer rotor; Phase difference And a pressure chamber constituted by the first member and the second member so that the volume thereof changes as a result of the control, and by operating the pressure in the pressure chamber with a working fluid supplied to the pressure chamber, A means for causing relative rotation between the rotors, a pressure detecting means for detecting the pressure in the pressure chamber, and an actual phase difference between the two rotors based on the pressure detected by the pressure detecting means; A phase difference parameter estimating means for estimating a value of the phase difference parameter using any one of the characteristic parameters of the motor having a predetermined correlation with the phase difference as a phase difference parameter; and the phase difference parameter And an energization control unit that controls energization of the electric motor based on the value of the phase difference parameter estimated by the estimation unit (first invention).

  According to the first aspect of the invention, the phase difference between the two rotors (outer rotor) is obtained by operating (increasing or decreasing) the pressure in the pressure chamber formed by the first member and the second member of the inter-rotor relative rotation means. And the rotation angle of the inner rotor) can be controlled to a required phase difference (target phase difference). In this case, the required phase difference can be arbitrarily determined according to various requirements. For example, when increasing the energy efficiency of the motor, the target phase difference may be determined so that the motor can be operated at an operating point where the energy efficiency is as high as possible.

  In the first invention, the phase difference between the two rotors (difference between the rotation angles of the outer rotor and the inner rotor) can be controlled by operating the pressure in the pressure chamber as described above. It defines the phase difference between the rotors. Therefore, based on the pressure in the pressure chamber detected by the pressure detection means, the phase difference between the rotors, or a predetermined correlation with this phase difference (for example, monotonously increasing or decreasing with respect to the change in phase difference) It is possible to estimate the value of the phase difference parameter, which is a characteristic parameter of an electric motor having such a relationship.

  Therefore, in the first invention, the phase difference parameter estimation means estimates the value of the phase difference parameter based on the pressure in the pressure chamber detected by the pressure detection means. The first invention performs energization control of the electric motor according to the estimated phase difference parameter. As a result, it is possible to operate the electric motor suitable for the state of the composite field by the permanent magnets of both rotors.

  Therefore, according to the first aspect of the invention, it is possible to change the phase difference between the outer rotor and the inner rotor according to various demands, and to operate the electric motor suitable for the actual phase difference. It becomes possible.

  Supplementally, in the present invention, the output shaft of the electric motor (the rotation shaft that outputs torque to the outside) is provided so as to be rotatable integrally with one of the outer rotor and the inner rotor. In this case, the other of the outer rotor and the inner rotor can rotate relative to the output shaft, but in a state where the phase difference between the rotors is kept constant, both rotors are integrated with the output shaft. It will rotate.

  Further, the magnetic force acting between the permanent magnet of the outer rotor and the permanent magnet of the inner rotor generates a rotational force that tries to rotate the other of the two rotors. In addition, the magnitude | size and direction of the rotational force by this magnetic force become a thing according to the phase difference between both rotors. Therefore, when the phase difference between the two rotors is maintained at a certain value, the pressure may be manipulated so that a rotational force that balances the rotational force due to the magnetic force is generated between the two rotors by the pressure in the pressure chamber.

  Further, the pressure detection means may not be a means for directly detecting the pressure in the pressure chamber by a sensor, and estimates the pressure from a detected value of a physical quantity having a correlation with the pressure in the pressure chamber (the It may be a means for indirectly detecting the pressure.

  In the first aspect of the invention, more specifically, the pressure chamber includes a first pressure chamber that generates a pressure for rotating the inner rotor relative to the outer rotor in a first direction, and the outer chamber. And a second pressure chamber that generates a pressure to rotate the inner rotor in a second direction opposite to the first direction with respect to the rotor, and the pressure detecting means includes the first pressure chamber. The first pressure detecting means and the second pressure detecting means for detecting respective pressures of the pressure chamber and the second pressure chamber. In this case, it is preferable that the phase difference parameter estimation means estimates the value of the phase difference parameter based on the pressures respectively detected by the first pressure detection means and the second pressure detection means ( Second invention).

  In the second aspect of the invention, relative rotation (change in phase difference) between the two rotors is performed by the differential pressure between the pressure in the first pressure chamber and the pressure in the second pressure chamber. Therefore, by estimating the value of the phase difference parameter based on the pressure respectively detected by the first pressure detecting means and the second pressure detecting means, the estimation can be performed appropriately. In this case, when the phase difference between the two rotors is maintained at a certain value, the first and second torques are generated between the two rotors by the differential pressure so as to generate a rotational force that balances the rotational force generated by the magnetic force. What is necessary is just to operate each pressure of a pressure chamber.

  For example, the first member and the second member in the second invention are configured as follows. That is, the first member is provided coaxially with the outer rotor, and a shaft portion that is provided integrally with the outer rotor so as to be relatively rotatable with respect to the inner rotor, and projects radially from the outer peripheral surface of the shaft portion. A plurality of first-member-side protrusions provided, and the second member is provided coaxially with the shaft portion of the first member, and the tip of the first-member-side protrusion is disposed on the inner periphery. An annular portion that is slidably contacted with the surface, and an inner peripheral surface of the annular portion, each projectingly provided at a position between each pair of first member side protrusions adjacent to each other in the circumferential direction of the shaft portion, A plurality of second member-side protrusions that are in sliding contact with the outer peripheral surface of the shaft portion, and one of each pair of first member-side protrusion portions adjacent to each other in the circumferential direction of the shaft portion. A space between the pair of first member-side protrusions and the second member-side protrusion is present as the first pressure chamber. The space between the other of the pair of first member side projections and the second member side projection located at a position between the pair of first member side projections is the second pressure chamber. (Third invention).

  According to the third aspect of the present invention, the first member side protrusion and the second member side protrusion are between the outer peripheral surface of the shaft portion of the first member and the inner peripheral surface of the annular portion of the second member. They are arranged alternately in the circumferential direction. At this time, the space between the first member side protrusion and the second member side protrusion adjacent to each other in the circumferential direction becomes the first or second pressure chamber, and these first and second pressure chambers The pressure chambers are formed alternately in the circumferential direction between the outer peripheral surface of the shaft portion of the first member and the inner peripheral surface of the annular portion of the second member. With such a configuration, the pressure in the first pressure chamber and the pressure in the second pressure chamber become pressures that cause the inner rotor to rotate in directions opposite to each other with respect to the outer rotor. Relative rotation between the rotors can be performed. With the relative rotation between the two rotors (relative rotation between the first member and the second member), the volume of one pressure chamber of the first and second pressure chambers increases while the pressure chamber of the other pressure chamber increases. The volume will decrease.

  According to the third aspect of the invention, the relative rotation between the rotors can be performed with a simple configuration of the first member and the second member.

  In the first to third aspects of the invention, there is provided a rotational speed detection means for detecting a rotational speed of an output shaft of an electric motor that is rotatably provided integrally with any one of the outer rotor and the inner rotor. The phase difference parameter estimating means is preferably means for estimating the value of the phase difference parameter based on the pressure detected by the pressure detecting means and the rotational speed detected by the rotational speed detecting means (first). 4 invention).

  That is, during rotation of the output shaft of the motor, particularly at high speed, the pressure for maintaining the phase difference between the two rotors at a certain value due to the inertial force even if the phase difference between the two rotors is constant. The chamber pressure value varies slightly. Therefore, by estimating the value of the phase difference parameter using not only the pressure detected by the pressure detecting means but also the rotational speed detected by the rotational speed detecting means, the accuracy of the estimated value can be estimated. Can be increased.

  In the first to fourth inventions, examples of the characteristic parameter of the motor include an induced voltage constant of the motor (fifth invention).

  This induced voltage constant is a constant that defines the relationship between the rotational speed of the output shaft of the motor and the induced voltage generated in the armature of the motor, and depends on the magnetic flux of the synthetic field. Since the composite field is determined corresponding to the phase difference between the two rotors, the induced voltage constant has a predetermined correlation with the phase difference between the two rotors. In this case, for example, when the phase difference between the two rotors where the magnetic flux of the synthetic field is maximized is used as a reference, the absolute value of the difference between the actual phase difference between the two rotors and the reference phase difference increases. The value of the induced voltage constant decreases monotonously. Therefore, the value of the induced voltage constant is estimated by the phase difference parameter estimating means, and the energization control of the motor is performed according to the estimated value, so that the energization control of the motor is performed according to the actual phase difference between the rotors. The same control as in the case of performing

  In the first to fifth inventions, a phase difference parameter command value output means for outputting a command value for the phase difference parameter, and a deviation between the command value for the phase parameter and the value of the estimated phase difference parameter And an operation command value determining means for determining an operation command value of the inter-rotor relative rotation means, and the inter-rotor relative rotation means preferably operates the pressure in the pressure chamber in accordance with the operation command value ( (Sixth invention).

  According to the sixth aspect of the invention, the operation command value of the inter-rotor relative rotation means is determined according to the deviation between the command value of the phase difference parameter and the estimated value of the phase difference parameter. The actual phase difference can be appropriately feedback controlled to the phase difference defined by the command value of the phase difference parameter.

  Supplementally, when determining the operation command value of the inter-rotor relative rotation means, not only the deviation but also the command value of the phase difference parameter may be used. For example, a feedforward value (basic operation command value) of the operation command value is determined according to the command value of the phase difference parameter, and the operation command value is determined by correcting this feedforward value according to the deviation. It may be.

  The operation command value may be a command value for the pressure in the pressure chamber or a command value for a phase difference between the rotors. In this case, when the operation command value is a command value of the phase difference between the two rotors, the command value of the phase difference may be converted into a command value of the pressure in the pressure chamber by the relative rotation means between the rotors. .

  Further, the phase difference parameter command value output means, for example, from a command value of the output torque of the electric motor, a detected value of the rotational speed of the output shaft of the electric motor, and a target value of the power supply voltage of the electric motor, by a map or the like, The command value of the phase difference parameter may be determined and output. In this case, for example, the phase difference parameter is set so that the generated voltage of the armature of the motor does not exceed the target value of the power supply voltage of the motor, and the motor can be operated in a state where the energy efficiency is high. The command value can be determined. Note that the command value of the phase difference parameter may be determined in consideration of a request for preventing overheating of the electric motor, for example. The command value of the phase difference parameter can be variously set according to the request regarding the operation mode of the electric motor.

  In the sixth aspect of the invention, when the operation command value is a command value of the pressure in the pressure chamber, the energization control unit is configured to calculate the command value of the pressure and the pressure detected by the pressure detection unit. It is preferable to provide means for operating the energization current of the electric motor in accordance with the deviation (hereinafter also referred to as pressure deviation) (seventh invention).

  Alternatively, when the operation command value is a command value of the phase difference between the two rotors, the energization control unit is configured to output the phase difference command value and the phase difference estimated by the phase difference parameter estimation unit. It is preferable to provide means for operating the energization current of the motor in accordance with a deviation from the value of the phase difference between the two rotors corresponding to the parameter value (hereinafter sometimes referred to as phase difference deviation) (eighth invention). ).

  According to these seventh and eighth inventions, the energization control means includes means for operating an energization current of the electric motor in accordance with the pressure deviation or phase difference deviation. Therefore, when the actual phase difference between the two rotors does not reach the phase difference corresponding to the command value of the phase difference parameter, the phase difference between the two rotors required by the operation command value (this is the final value) In practice, it is possible to compensate for the deviation between the synthesized field of the permanent magnet and the actual synthesized field at the phase difference corresponding to the command value of the phase difference parameter by the energization current of the motor. It becomes. That is, the deviation of the combined field of the permanent magnets due to the delay of the actual phase difference with respect to the phase difference between the two rotors required by the operation command value can be compensated by the field due to the energization current of the motor. As a result, the electric motor required by the phase difference between the rotors corresponding to the command value of the phase difference parameter before the actual phase difference between the rotors reaches the phase difference corresponding to the command value of the phase difference parameter. This makes it possible to perform an operation equivalent to the above operation, and improve the responsiveness of the electric motor.

  In the seventh invention or the eighth invention, the energization control means is a so-called dq vector control (rotational coordinate system (dq coordinate system) fixed with respect to the output shaft of the motor). (Control method for handling the current flowing through the electric element as a combined current of a d-axis current (field current) as a current component in the field direction and a q-axis current (torque current) as a current component orthogonal to the field direction) Therefore, when the energization control of the electric motor is performed, the d-axis current may be operated according to the pressure deviation or the phase difference deviation.

  In the seventh invention or the eighth invention, more specifically, the energization control means estimates the command value of the output torque of the motor and the detected value of the rotational speed of the output shaft of the motor, for example. And a current command value determining means for determining a command value (basic command value) of the energization current of the motor based on the input value of the phase difference parameter. The means for operating the energization current of the motor corrects the command value of the energization current (for example, the command value of the d-axis current) according to the pressure deviation or the phase difference deviation, and What is necessary is just to control the energization current of an electric motor according to command value.

  In the first to eighth aspects of the present invention, it is preferable that the present invention further comprises abnormality detection means for determining whether or not the rotor relative rotation means is abnormal based on the pressure detected by the pressure detection means (9th invention).

  That is, when the relative rotation means between the rotors is operating normally, the pressure detected by the pressure detection means changes within a certain range. Therefore, the abnormality of the relative rotation means between the rotors (based on the detected pressure ( For example, it is possible to determine the presence or absence of leakage of the working fluid or malfunction of the first member or the second member. When the ninth aspect of the invention is combined with the second aspect of the invention, the rotor relative rotation means is based on the pressure sets detected by the first pressure detecting means and the second pressure detecting means. The presence or absence of abnormality will be judged.

  An embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a cross-sectional view of a main part of the electric motor according to the present embodiment, and FIG. 2 is a view as seen in the axial direction of the electric motor with the drive plate 19 of the electric motor of FIG. 1 removed.

  Referring to FIG. 1, this electric motor 1 is a DC brushless motor having a double rotor structure, and includes an output shaft 2, an outer rotor 3, and an inner rotor 4 coaxially. A stator 5 fixed to a housing (not shown) of the electric motor 1 is provided outside the outer rotor 3, and an armature (three-phase armature) not shown is attached to the stator 5. . The electric motor 1 is mounted on a vehicle as a driving power source for a hybrid vehicle or an electric automobile, for example, and can operate as a motor (powering operation) and operate as a generator (regenerative operation). .

  The outer rotor 3 is formed in an annular shape, and includes a plurality of permanent magnets 6 arranged at substantially equal intervals in the circumferential direction. The permanent magnet 6 is formed in the shape of a long rectangular plate, and the outer side of the permanent magnet 6 is oriented in the axial direction of the outer rotor 3 and the normal direction is directed in the radial direction of the outer rotor 3. Embedded in the rotor 3. Further, the outer rotor 3 is provided with a plurality of screw holes 7 having an axis parallel to the axis. These screw holes 7 are arranged at equal intervals in the circumferential direction of the outer rotor 3.

  The inner rotor 4 is also formed in an annular shape. The inner rotor 4 is disposed coaxially with the outer rotor 3 on the inner side of the outer rotor 3 with the outer peripheral surface thereof being in sliding contact with the inner peripheral surface of the outer rotor 3. A slight clearance may be provided between the outer peripheral surface of the inner rotor 4 and the inner peripheral surface of the outer rotor 3. Further, the output shaft 2 passes through the axial center portion of the inner rotor 4 coaxially with the inner rotor 4 and the outer rotor 3. In this case, the inner diameter of the inner rotor 4 is larger than the outer diameter of the output shaft 2, and there is a gap between the outer peripheral surface of the output shaft 2 and the inner peripheral surface of the inner rotor 4.

  Further, the inner rotor 4 includes a plurality of permanent magnets 8 arranged at substantially equal intervals in the circumferential direction. The permanent magnet 8 has the same shape as the permanent magnet 6 of the outer rotor 3 and is embedded in the inner rotor 4 in the same form as that of the outer rotor 3. The number of permanent magnets 8 in the inner rotor 4 is the same as the number of permanent magnets 8 in the outer rotor 3.

  Here, with reference to FIG. 2, the permanent magnet 6 a shown in white among the permanent magnets 6 of the outer rotor 3 and the permanent magnet 6 b with stippling indicate that the magnetic poles are oriented in the radial direction of the outer rotor 3. They are opposite to each other. For example, the permanent magnet 6a has an N pole on the outer side (outer peripheral surface side of the outer rotor 4) and an S pole on the inner side (inner peripheral surface side of the outer rotor 3), and the permanent magnet 6b has an outer side. This surface is the S pole and the inner surface is the N pole. Similarly, the permanent magnet 8a shown in white among the permanent magnets 8 of the inner rotor 4 and the dotted permanent magnet 8b are opposite to each other in the direction of the magnetic poles in the radial direction of the inner rotor 4. . For example, the permanent magnet 8a has an N-pole surface on the outer side (the outer peripheral surface side of the inner rotor 4) and an S-pole surface on the inner side (the inner peripheral surface side of the inner rotor 4). This surface is the S pole and the inner surface is the N pole.

  In the present embodiment, in the outer rotor 4, as shown in FIG. 2, the pair of permanent magnets 6 a and 6 a adjacent to each other and the pair of permanent magnets 6 b and 6 b adjacent to each other are combined with each other. Are arranged alternately in the circumferential direction. Similarly, in the inner rotor 4, pairs of permanent magnets 8 a and 8 a adjacent to each other and pairs of permanent magnets 8 b and 8 b adjacent to each other are alternately arranged in the circumferential direction of the inner rotor 4. .

  A first member 9 and a second member 10 are provided between the inner rotor 4 and the outer peripheral surface of the output shaft 2.

  The second member 10 includes an annular portion 11 and a plurality of projecting portions (second member-side projecting portions) 12 projecting radially from the inner peripheral surface of the annular portion 11 toward the central portion of the annular portion 11. And have. The second member 10 is fixed coaxially to the inner rotor 4 by fitting the annular portion 11 coaxially to the inner rotor 4. Further, the protrusions 12 of the second member 10 are provided at equal intervals in the circumferential direction.

  The first member 9 has a vane rotor shape, and includes an annular portion 13 as a shaft portion thereof, and a plurality of protrusions (first member side protrusions) protruding in a radial direction from the outer peripheral surface of the annular portion 13. 14. The annular portion 13 of the first member 9 is provided coaxially with the annular portion 11 on the inner side of the annular portion 11 of the second member 10, and the distal end portion of each protrusion 12 of the second member 10 is sealed on the outer peripheral surface thereof. It is in sliding contact with the member 15. Further, the annular portion 13 of the first member 9 is extrapolated to the output shaft 2, and an inner peripheral surface thereof is fitted to a spline 16 formed on the outer peripheral surface of the output shaft 2. The first member 9 can rotate integrally with the output shaft 2 by this spline fitting.

  The number of protrusions 14 of the first member 9 is the same as the number of protrusions 12 of the second member 10 and is arranged at equal intervals in the circumferential direction. In this case, each protrusion 14 of the first member 9 is interposed at a location between the two protrusions 12, 12 adjacent to each other in the circumferential direction of the second member 10. In other words, the first member 9 and the second member 10 are engaged so that their protrusions 14 and 12 are alternately arranged in the circumferential direction. And the front-end | tip part of each projection part 14 of the 1st member 9 is slidably contacted by the internal peripheral surface of the cyclic | annular part 11 of the 2nd member 10 via the sealing member 17. FIG. Each projection 14 of the first member 9 has a screw hole 18 having an axis parallel to the axis of the annular portion 13.

  With reference to FIG. 1, disk-shaped drive plates 19, 19 are mounted coaxially with the outer rotor 3 at both end surfaces in the axial direction of the outer rotor 3. Each of these drive plates 19, 19 has a hole 20 having a diameter larger than the outer diameter of the output shaft 2 at its center (axial center), and the output shaft 2 passes coaxially through this hole 20. In addition, each end of the annular portion 13 of the first member 9 is fitted into the hole 20. Each drive plate 19 is fastened to each screw hole 7 of the outer rotor 3 and each screw hole 18 of each protrusion 14 of the first member 9 by bolts 21. Thereby, the outer rotor 3 and the 1st member 9 are connected so that rotation is possible integrally. In this case, since the first member 9 can rotate integrally with the output shaft 2 by spline fitting as described above, the outer rotor 3 can also rotate integrally with the output shaft 2.

  The drive plates 19 and 19 support the inner rotor 4 and the second member 10 between them. Specifically, annular grooves 22 are formed coaxially on the mutually opposing surfaces of the drive rates 19 and 19, respectively. Then, each end of the annular portion 11 of the second member 10 is slidably inserted into the annular groove 22. As a result, the inner rotor 4 and the second member 10 are supported by the drive plates 19 and 19 via the annular portion 11, and along the annular groove 22 of the drive plates 19 and 19, the outer rotor 3 and the first member. 9 and the output shaft 2 are rotatable relative to each other.

  The first member 9 and the second member 10 are components of the inter-rotor relative rotation means 23 that rotates the inner rotor 3 relative to the outer rotor 4. The inter-rotor relative rotation means 23 is surrounded by the annular portion 13 of the first member 9, the annular portion 11 of the second member 10, and the drive plates 19, 19 by the first member 9 and the second member 10. In this space, a plurality of pairs (the same number of pairs as the protrusions 12 and 14) of pressure chambers 24 and 25 are formed as shown in FIG. These pressure chambers 24 and 25 correspond to the first pressure chamber and the second pressure chamber in the present invention. More specifically, in the space between the annular portion 11 of the second member 10 and the annular portion 13 of the first member 9, each protrusion 12 of the second member 10 and both sides (circumferential direction) of the protrusion 12. The spaces between the two protrusions 14 and 14 of the first member 9 on both sides of the first member 9 are pressure chambers 24 and 25 for flowing in and out working oil as working fluid, respectively. In this case, the pressure chamber 24 on one side of each projecting portion 12 of the second member 10 is formed in the annular portion 13 of the first member 9 in the oil passage 26 provided inside the output shaft 2. The hydraulic fluid is filled through communication through an oil passage (not shown). Similarly, the pressure chamber 25 on the other side of each protrusion 12 of the second member 10 is connected to an oil passage 27 provided separately from the oil passage 26 inside the output shaft 2, and the annular portion 13 of the first member 9. The hydraulic fluid is filled through a fluid passage (not shown) formed in the pipe. In this case, the pressure (hydraulic pressure) in the pressure chamber 24 becomes a pressure for rotating the inner rotor 4 relative to the outer rotor 3 in the clockwise direction in FIG. Further, the pressure (hydraulic pressure) of the pressure chamber 24 becomes a pressure to rotate the inner rotor 4 relative to the outer rotor 3 in the counterclockwise direction of FIG. 2 when the pressure is increased.

  As shown in FIG. 1, the inter-rotor relative rotation means 23 includes a hydraulic power source device 30 connected to the oil passages 26 and 27 of the output shaft 2 outside the electric motor 1. The hydraulic power source device 30 increases or decreases the pressure in each pressure chamber 24, 25 by controlling the supply of hydraulic oil to each pressure chamber 24, 25. In this case, due to the pressure difference between the pressure chambers 24 and 25, a rotational force is generated to rotate the inner rotor 4 together with the second member 10 with respect to the outer rotor 3 and the first member 9. That is, by making the pressure of the pressure chamber 24 larger than that of the pressure chamber 25, a rotational force is generated to rotate the inner rotor 4 in the clockwise direction of FIG. To do. On the contrary, by making the pressure in the pressure chamber 25 larger than that in the pressure chamber 23, a rotational force for rotating the inner rotor 4 with respect to the outer rotor 3 in the counterclockwise direction of FIG. appear. Therefore, the inter-rotor relative rotation means 23 rotates the inner rotor 4 with respect to the outer rotor 3 by increasing or decreasing the pressures of the pressure chambers 24 and 25 and operating the pressure difference therebetween (both rotors 3 and 3). 4).

  Supplementally, due to the magnetic force acting between the permanent magnets 8 a and 8 b of the inner rotor 4 and the permanent magnets 6 a and 6 b of the outer rotor 3, the inner rotor 4 becomes permanent between the permanent magnets 8 a and 8 b and the outer rotor 3. The magnets 6a and 6b try to balance in a state where the opposite poles face each other (the permanent magnets 8a and 8b face the permanent magnets 6a and 6b, respectively). For this reason, when the inner rotor 4 is rotated with respect to the outer rotor 3 from the equilibrium state, a torque (hereinafter sometimes referred to as a magnetic torque) for returning the inner rotor 4 to the equilibrium state is generated. For this reason, when the inner rotor 4 is rotated relative to the outer rotor 3 due to the pressure difference between the pressure chambers 24 and 25, a rotational force against the magnetic torque is applied to the inner rotor 4 via the second member 10. Thus, it is necessary to manipulate the pressure in the pressure chambers 24 and 25. Note that the magnetic torque changes according to the phase difference between the inner rotor 4 and the outer rotor 3.

  A first pressure sensor 28 serving as a first pressure detecting means for detecting the pressure P <b> 1 of the pressure chamber 24 is provided in the oil passage 26 a that connects the hydraulic power source device 30 and the oil passage 26 of the output shaft 2. . Further, a second pressure sensor 29 as a second pressure detecting means for detecting the pressure P2 of the pressure chamber 25 is provided in the oil passage 27a that connects the hydraulic device 23 and the oil passage 27 of the output shaft 2.

  The above is the mechanical configuration of the electric motor 1 and the interrotor relative rotation means 23.

  In the present embodiment, the output shaft 2 and the outer rotor 3 of the electric motor 1 are configured to rotate integrally. However, the output shaft and the inner rotor are configured to rotate integrally so that the output shaft and the inner rotor rotate. You may comprise so that an outer rotor can rotate relatively with respect to a rotor. Further, the configurations of the first member and the second member are not limited to the configurations described above.

  A field generated by the permanent magnets 8a and 8b of the inner rotor 4 by rotating the inner rotor 4 with respect to the outer rotor 3 and changing the phase difference between the rotors 3 and 4 by the relative rotation means 23 between the rotors. The strength of the combined magnetic field (radial magnetic flux toward the stator 5) of the magnetic field and the field generated by the permanent magnets 6a and 6b of the outer rotor 3 changes. Hereinafter, the combined magnetic flux is referred to as a combined magnetic flux, the state in which the combined magnetic flux is maximized is referred to as a field strengthened state, and the state in which the combined magnetic flux is minimum is referred to as a field weakened state. FIG. 3A is a diagram showing a phase relationship between the inner rotor 4 and the outer rotor 3 in the field strengthened state, and FIG. 3B is a diagram of the inner rotor 4 and the outer rotor 3 in the field weakened state. It is a figure which shows a phase relationship.

  As shown in FIG. 3A, the field strengthened state is a state in which the permanent magnets 8a and 8b of the inner rotor 4 and the permanent magnets 6a and 6b of the outer rotor 3 are opposed to each other. More specifically, in this field strong state, the permanent magnet 8a of the inner rotor 4 faces the permanent magnet 6a of the outer rotor 3, and the permanent magnet 8b of the inner rotor 4 faces the permanent magnet 6b of the outer rotor 3. In this state, in the radial direction, the direction of the magnetic flux Q1 of the permanent magnets 8a and 8b of the inner rotor 4 and the direction of the magnetic flux Q2 of the permanent magnets 6a and 6b of the outer rotor 3 are the same. The strength of the combined magnetic flux Q3 of the magnetic fluxes Q1 and Q2 is maximized. This field strengthening state is the equilibrium state.

  Further, as shown in FIG. 3B, the field weakening state is a state in which the permanent magnets 8a and 8b of the inner rotor 4 and the permanent magnets 6a and 6b of the outer rotor 3 face each other. More specifically, in this field-enhanced state, the permanent magnet 8 a of the inner rotor 4 faces the permanent magnet 6 b of the outer rotor 3, and the permanent magnet 8 b of the inner rotor 4 faces the permanent magnet 6 a of the outer rotor 3. In this state, the direction of the magnetic flux Q1 of the permanent magnets 8a and 8b of the inner rotor 4 and the direction of the magnetic flux Q2 of the permanent magnets 6b and 6a of the outer rotor 3 are opposite in the radial direction. The strength of the combined magnetic flux Q3 of these magnetic fluxes Q1 and Q2 is minimized.

  In this embodiment, the phase difference between the inner rotor 4 and the outer rotor 3 in the field-enhanced state (the phase of the inner rotor 4 with respect to the outer rotor 3; hereinafter referred to as the inter-rotor phase difference) is 0 [deg], The phase difference between the rotors in the field weakening state is defined as 180 [deg].

  FIG. 4 is a graph comparing the induced voltages induced in the armature of the stator 5 when the output shaft 2 of the electric motor 1 is operated at a predetermined rotational speed in the field strengthening state and the field weakening state. is there. The vertical axis and horizontal axis of this graph are the induced voltage [V] and the rotation angle [degree] of the output shaft 2 in electrical angle, respectively. A graph with reference symbol a is a graph in a field strengthened state (state where rotor phase difference is 0 [deg]), and a graph with reference symbol b is a field weakened state (phase difference between rotors). = 180 [deg] state). As can be seen from FIG. 4, the level of the induced voltage (amplitude level) can be changed by changing the inter-rotor phase difference between 0 [deg] and 180 [deg]. Note that when the inter-rotor phase difference is increased to 0 [deg] and 180 [deg], the resultant magnetic flux decreases, and the induced voltage level decreases accordingly.

  Thus, the induced voltage constant Ke of the electric motor 1 can be changed by changing the phase difference between the rotors to increase or decrease the magnetic flux of the field. The induced voltage constant Ke is a proportional constant that defines the relationship between the angular velocity of the output shaft 2 of the electric motor 1 and the induced voltage generated in the armature according to the angular velocity. As will be described later, the value of the induced voltage constant Ke decreases as the inter-rotor phase difference is increased from 0 [deg] to 180 [deg].

  Next, a control device (control system) for the electric motor 1 in the present embodiment will be described with reference to FIGS. FIG. 5 is a block diagram illustrating a functional configuration of a control device (hereinafter simply referred to as a control device) of the electric motor 1, and FIGS. 6 to 8 are diagrams for explaining processing of a Ke calculation unit 47 provided in the control device. FIG. 9 is a flowchart showing the processing of the Ke calculation unit 47. In FIG. 5, the electric motor 1 is schematically illustrated and a mechanism including the first member 9 and the second member 10 is expressed as a “phase variable mechanism”.

  The control device of the present embodiment controls energization of the electric motor 1 by so-called dq vector control. That is, the control device converts the electric motor 1 into an equivalent circuit in the dq coordinate system, which is a two-phase DC rotating coordinate system in which the field direction is the d axis and the direction orthogonal to the d axis is the q axis. handle. The equivalent circuit has an armature on the d-axis (hereinafter referred to as d-axis armature) and an armature on the q-axis (hereinafter referred to as q-axis armature). The dq coordinate system is a coordinate system fixed with respect to the output shaft 2 of the electric motor 1. Then, the control device controls the energization current of the armature (three-phase armature) of the electric motor 1 so that the torque corresponding to the torque command value Tc given from the outside is output from the output shaft 2 of the electric motor 1. In parallel with this energization control, the control device determines the command value Ke_c of the induced voltage constant Ke of the electric motor 1 according to the torque command value Tc and the like, and estimates the actual induced voltage constant Ke of the electric motor 1. Then, the inter-rotor phase difference is controlled via the inter-rotor relative rotation means 23 so that the estimated value of Ke coincides with the command value Ke_c.

  In order to perform these controls, in the present embodiment, the first and second pressure sensors 28 and 29 are provided as sensors, and two of the three phases of the armature of the motor 1, for example, the U phase. And current sensors 41 and 42 (current detection means) for detecting currents in the W phase and the rotation angle of the output shaft 2 of the electric motor 1 (in the present embodiment, this is equal to the rotation angle of the outer rotor 3). And a resolver 43 (rotation angle detection means).

  The control device is an electronic unit including a CPU, a memory, and the like, and its control processing is sequentially executed at a predetermined calculation processing cycle. The functional means of the control device will be specifically described below.

  As a functional means, the control device removes unnecessary components from the output signals of the current sensors 41 and 42, thereby obtaining the U-phase and W-phase current detection values Iu and Iw, Based on the current detection values Iu and Iw and the rotation angle θm of the output shaft 2 detected by the resolver 43, detection of the current of the d-axis armature (hereinafter referred to as d-axis current) by three-phase-dq conversion The motor 1 by differentiating the rotation angle θm detected by the resolver 43 and the three-phase-dq converter 45 that calculates the value Id and the detected value Iq of the q-axis armature current (hereinafter referred to as q-axis current). The differential calculation part 46 which detects the rotational speed Nm of the output shaft 2 and the Ke calculation part 47 which estimates the actual induced voltage constant Ke of the electric motor 1 are provided.

  In the present embodiment, an induced voltage constant Ke which is one of the characteristic parameters of the electric motor 1 is used as the phase difference parameter in the present invention. Therefore, the Ke calculation unit 47 corresponds to the phase difference parameter estimation means in the present invention. Details of the Ke calculation unit 47 will be described later. The differential calculation unit 46 corresponds to the rotation speed detection means in the present invention.

  The control device is further obtained by the Ke command calculation unit 49 for determining the command value Ke_c of the induced voltage constant, the command value Ke_c of the induced voltage constant determined by the Ke command calculation unit 49 and the Ke calculation unit 47. Based on the calculation unit 57 for obtaining the deviation ΔKe (= Ke_c−Ke) from the estimated value of the induced voltage constant Ke and the deviation ΔKe and the command value Ke_c of the induced voltage constant, the command values of the pressures P1 and P2 are And a hydraulic pressure control unit 58 that determines certain pressure command values P1_c and P2_c and outputs the determined pressure command values P1_c and P2_c to the hydraulic power source device 30.

  The Ke command calculation unit 49 includes a torque command value Tc given from the outside of the control device, the rotation speed Nm (detection value) of the output shaft 2 of the motor 1 detected by the processing of the differential calculation unit 46, and the motor 1. The command value Ke_c of the induced voltage constant is determined from the power supply voltage Vdc (target value) of the power supply voltage Vdc based on a preset map. In this case, the map shows, for example, the generated voltage of the d-axis armature and the generated voltage of the q-axis armature for the set of the torque command value Tc, the rotation speed Nm (detected value), and the power supply voltage Vdc. The command value Ke_c that can increase the energy efficiency (ratio of output energy to input energy) of the motor 1 as much as possible while determining the magnitude of the combined voltage (vector sum) of the motor 1 and the power supply voltage Vdc is determined. Is set to

  Here, generally, the smaller the induced voltage constant Ke (in other words, the greater the phase difference between the rotors), the more the output shaft 2 of the electric motor 1 can be rotated in a higher speed range. The region where the energy efficiency of the electric motor 1 is high can be shifted to the high speed rotation side. Further, the torque that can be generated by the electric motor 1 can be increased as the induced voltage constant Ke is increased (in other words, the phase difference between the rotors is decreased). Therefore, the command value Ke_c of the induced voltage constant may be set in consideration of the characteristics of the electric motor 1 with respect to the induced voltage constant Ke as described above and the operation mode required of the electric motor 1, and various setting methods are possible. Is possible.

  When the electric motor 1 is mounted on a vehicle as a driving power source for the vehicle, the torque command value Tc is set according to, for example, the accelerator operation amount or the traveling speed of the vehicle. In addition to the energy efficiency of the electric motor 1, the map may be set in consideration of requests for preventing overheating of the electric motor 1.

  The hydraulic pressure control unit 58 corresponds to the operation command value determining means in the present invention, and determines the pressure command values P1_c and P2_c as operation command values for the inter-rotor relative rotation means 23. Details of the processing of the hydraulic control unit 58 will be described later.

  The control device further includes a current command calculation unit as a current command value determination unit that determines a d-axis current command value Id_c that is a command value for the d-axis current and a q-axis current command value Iq_c that is a command value for the q-axis current. 48.

  The current command calculation unit 48 includes the torque command value Tc, the rotation speed Nm of the output shaft 2 of the motor 1 detected by the processing of the differentiation calculation unit 46, and the motor 1 obtained by the Ke calculation amount 47. Based on the estimated value of the induced voltage constant Ke, the d-axis current command value Id_c and the q-axis current command value Iq_c are determined based on a preset map.

  Then, the control device obtains a correction value ΔId_vol for correcting the d-axis current command value Id_c among the d-axis current command value Id_c and the q-axis current command value Id_c determined by the current command calculation unit 48; By adding the correction value ΔId_vol to the d-axis current command value Id_c, a calculation unit 50 for obtaining a corrected d-axis current command value Id_c ′, the corrected d-axis current command value Id_c, and the q-axis current command value Id_c Deviations ΔId (= Id_c−Id) and ΔIq (= Iq_c−Iq) between the detected value Id of the d-axis current and the detected value Iq of the q-axis current obtained by the three-phase-dq converter 45, respectively. Are provided with calculation units 53 and 51, respectively.

  Here, in this embodiment, the field control unit 52 receives the pressures P1 and P2 detected by the pressure sensors 28 and 29, and the pressure command values P1_c and P2_c determined by the hydraulic control unit 58, respectively. In accordance with the deviation between P1 and P1_c and the deviation between P2 and P2_c, the correction value ΔId_vol is calculated by a feedback control law or the like so that these deviations approach 0. The correction value ΔId_vol is the pressure command value P1_c until the actual rotor phase difference reaches the rotor phase difference corresponding to the induced voltage constant command value Ke_c when the induced voltage constant command value Ke_c is changed. , P2_c to compensate for the deviation between the combined field of the permanent magnets 6 and 8 at the rotor phase difference and the combined field at the rotor phase difference corresponding to the actual rotor phase difference Ke ( This means an operation amount of the d-axis current for compensating the deviation of the combined field by a field due to the d-axis current (field current).

  Further, the control device uses the feedback control law such as the PI control law to make the deviations ΔId and Iq close to 0 in accordance with the deviations ΔId and ΔIq calculated as described above. The current feedback control unit 54 determines a d-axis voltage command value Vd_c that is a value and a q-axis voltage command value Vq_c that is a voltage command value of the q-axis armature. When the d-axis voltage command value Vd_c and the q-axis voltage command value Vq_c are determined, the d-axis voltage command value and the q-axis voltage command value respectively obtained from the deviations ΔId and Iq by a Fordback control law such as a PI control law. In addition, it is preferable to obtain the d-axis voltage command value Vd_c and the q-axis voltage command value Vq_c by adding a non-interference component for canceling the influence of the speed electromotive force that interferes between the d-axis and the q-axis. .

  Furthermore, the control device includes an rθ conversion unit 55 that converts a vector having components of the d-axis voltage command value Vd_c and the q-axis voltage command value Vq_c into a component of the magnitude V1 and a component of the angle θ, A PWM calculation unit 56 is provided that converts the component of the magnitude V1 and the angle θ into a three-phase AC voltage by PWM control and energizes the armature of each phase of the electric motor 1.

  Supplementally, the current command calculation unit 48, the calculation units 50, 51, and 53, the field control unit 52, the current feedback control unit 54, the rθ conversion unit 55, and the PWM calculation unit 56, that is, a portion surrounded by a broken line in FIG. Thus, the energization control means in the present invention is configured.

  In the field control unit 52, as a simple method, the phase voltage obtained from the d-axis voltage command value Vd_c and the q-axis voltage command value Vq_c traces the target voltage circle obtained from the power supply voltage Vdc ( In other words, the correction value ΔId_vol for manipulating the d-axis current Id may be determined so that the combined vector of Vd_c and Vq_c matches Vdc as the radius of the target voltage circle. .

  Next, the Ke calculation portion 47 will be described in more detail. In this Ke calculation unit 47, in order to estimate the induced voltage constant Ke as a phase difference parameter, the detected value of the rotational speed Nm obtained by the differential calculation unit 46 and the first and second pressure sensors 38, 39 are detected. The pressures P1 and P2 detected in step S1 are input.

  Here, in this embodiment, when controlling the phase difference between the rotors, basically, the pressures P1 and P2 of the pressure chambers 24 and 25 are in a form along the graphs c and d in FIG. Change. That is, for the pressure P1, as shown in the graph c, the inter-rotor phase difference θ is calculated as follows: a phase difference in the field strong state (= 0 degree) and a phase difference in the field weak state (= 180 degree). P1 increases monotonously as the inter-rotor phase difference θd increases. When the inter-rotor phase difference θd becomes larger than the predetermined value θdx, P1 is maintained at a value substantially equal to the value of P1 at the predetermined value θdx.

  On the other hand, with respect to the pressure P2, as shown in the graph d, when the inter-rotor phase difference θd is equal to or less than the predetermined value θdx, P2 is maintained at substantially zero. When the inter-rotor phase difference θ becomes larger than the predetermined value θdx, P2 monotonously increases as the inter-rotor phase difference θd increases. The increase in P2 is performed so as to coincide with P1 when the inter-rotor phase difference θd is 180 degrees. Thus, by changing the pressures P1 and P2, the pressure difference (P1−P2) has a peak value in the vicinity of the predetermined value θdx as shown by the graph e in FIG. (Convex form). The pressures P1 and P2 are thus changed with respect to the inter-rotor phase difference θd because the magnetic torque that is opposite to the torque acting on the inner rotor 4 due to the pressure difference (P1-P2) is the phase difference between the rotors. This is because θd changes in the same manner as the graph e in FIG. That is, the pressures P1 and P2 are changed with respect to the inter-rotor phase difference θd so that the torque acting on the inner rotor 4 is substantially balanced with the magnetic torque by the pressure difference P1-P2.

  In the present embodiment, correlation data (table) representing the relationship between the rotor phase difference θd and P1 and P2 as shown in the graphs c and d is predetermined and stored in the memory of the control device. . In this case, the relationship between the rotor phase difference θ and P1 and P2 depends on the rotational speed Nm of the output shaft 2 of the electric motor 1 due to the influence of the inertia force during rotation of the inner rotor 4 and the outer rotor 3. Change a little. For this reason, in the present embodiment, the correlation data is provided for each rotation speed Nm of the output shaft 2 of the electric motor 1 (more precisely, corresponding to each of a plurality of rotation speed Nm values). Then, the Ke calculation unit 47 estimates the inter-rotor phase difference θd based on the correlation data from the input detection value of the rotational speed Nm and the detection values of the pressures P1 and P2. For example, if the detected values of pressures P1 and P2 at a certain rotational speed Nm are P1a and P2a shown in FIG. 6, respectively, θda shown in FIG. 4 is obtained as an estimated value of the inter-rotor phase difference θd. The correlation between the detected value of the rotational speed Nm, the detected values of the pressures P1 and P2, and the inter-rotor phase difference θd is mapped, and an estimated value of the inter-rotor phase difference θd is obtained based on the map. May be. Further, when the electric motor 1 is operated only in the low speed region, the inter-rotor phase difference θd may be estimated from only the detected values of the pressures P1 and P2.

  The inter-rotor phase difference θd estimated as described above has a close correlation with the induced voltage constant Ke of the electric motor 1. That is, the inter-rotor phase difference θd and the induced voltage constant Ke have a correlation as shown by the graph f in FIG. 7, and the induced voltage constant Ke decreases as the inter-rotor phase difference θd increases. This is because the strength of the combined magnetic flux decreases as the inter-rotor phase difference θd increases.

  Therefore, in the present embodiment, correlation data representing the relationship between the rotor phase difference θd and the induced voltage constant Ke as shown by the graph f in FIG. 7 is stored and held in the memory of the control device. Then, the Ke calculating unit 47 obtains an estimated value of the induced voltage constant Ke based on the correlation data from the estimated value of the inter-rotor phase difference θd obtained as described above.

  The correlation between the rotational speed Nm, the pressures P1 and P2, and the induced voltage constant Ke (or the correlation between the pressures P1 and P2 and the induced voltage constant Ke) is mapped, and Nm is detected based on the map. The estimated value of the induced voltage constant Ke may be obtained directly from the value and the detected values of P1 and P2 (or from the detected values of P1 and P2).

  As described above, by using the detected values of the pressures P1 and P2, the actual rotor phase difference θd can be appropriately estimated, and the actual induced voltage constant Ke can be appropriately estimated.

  Further, in the present embodiment, the Ke calculation unit 47 is based on the detected values of the pressures P1 and P2, and abnormalities in the hydraulic system constituting the inter-rotor relative rotation means 23 (the hydraulic power source device 30 and the first member 9, the first member 9). It also has a function of checking malfunctions of the two members 10 and abnormalities such as oil leakage. Specifically, the Ke calculation unit 47 determines that the combination of the detected values of the pressures P1 and P2 is an area AR (area in a coordinate system in which the horizontal axis is P1 and the vertical axis is P2) surrounded by a broken line in FIG. ), It is determined that the inter-rotor relative rotation means 23 is functioning normally. The area AR is an area where a point determined by a set of values of P1 and P2 that can be obtained when P1 and P2 are changed in the form shown by the graphs c and d in FIG. Further, the Ke calculation unit 47 determines that an abnormality of the inter-rotor relative rotation means 23 has occurred when the combination of the detected values of the pressures P1 and P2 deviates from the area AR. When the abnormality is determined, an error signal indicating that is output to the outside. For example, when the combination of the detected values of the pressures P1 and P2 is represented by the point A1 in FIG. 8, it is determined that the inter-rotor relative rotation unit 23 is normal. Further, when the combination of the detected values of the pressures P1 and P2 is represented by the point A2 in FIG. 8, it is determined that an abnormality in the inter-rotor relative rotation means 23 has occurred, and an error signal is output from the Ke calculation unit 47. Is done. The error signal is used for notifying the occurrence of an abnormality and for stopping the operation of the electric motor 1.

  The processing of the Ke calculating unit 47 described above is executed as shown in the flowchart of FIG. That is, in STEP1, the Ke calculation unit 47 acquires the detected values of the rotational speed Nm and the pressures P1 and P2. Next, the Ke calculation unit 47 determines whether or not the combination of the detection values of P1 and P2 is normal depending on whether or not the combination of the detection values of P1 and P2 exists in the area AR of FIG. (STEP2). At this time, when it is determined that the combination of the detected values of P1 and P2 is normal, the Ke calculating unit 47 obtains the estimated value of the inter-rotor phase difference θ from the detected values of P1, P2, and Nm as described above. (STEP3). Further, the Ke calculator 47 obtains an estimated value of the induced voltage constant Ke from the estimated value of the rotor phase difference θ as described above (STEP 4).

  If it is determined in STEP2 that the combination of the detected values of P1 and P2 is abnormal, the Ke calculation unit 47 outputs an error signal (STEP5). In this case, since the phase difference θ between the rotors and the induced voltage constant Ke cannot be estimated properly, the Ke calculation unit 47 does not execute the processes of STEPs 3 and 4.

  The details of the processing of the Ke calculation unit 47 have been described above. Supplementally, the determination process of STEP 2 executed by the Ke calculation unit 47 corresponds to the abnormality detection means in the present invention.

  Next, processing of the hydraulic control unit 58 will be described. In the hydraulic control unit 58, first, the correlation data between the induced voltage constant Ke and the inter-rotor phase difference θd shown in FIG. 7 from the command value Ke_c of the induced voltage constant input from the Ke command calculation unit 49. Is obtained as a command value of the inter-rotor phase difference θd corresponding to the command value Ke_c (the command value Ke_c is converted into a command value of the inter-rotor phase difference θd). Then, based on the obtained command value of the inter-rotor phase difference θd, the feedforward command values of the pressures P1 and P2 are determined based on the correlation data determined in advance as shown by the graphs c and d in FIG. . Further, each feedforward command value is corrected in accordance with the deviation ΔKe input from the calculation unit 57 (for example, a value obtained by multiplying ΔKe by a certain gain is added to the feedforward command value), whereby the pressure command Values P1_c and P2_c are determined. Thereby, the pressure command values P1_c and P2_c are determined so that the deviation ΔKe approaches 0 (the actual induced voltage constant Ke is made to coincide with the command value Ke_c).

  The hydraulic pressure source device 30 of the inter-rotor relative rotation means 23 operates the pressures P1 and P2 according to the pressure command values P1_c and P2_c. That is, the supply of hydraulic oil to the pressure chambers 24 and 25 is controlled so that the respective pressures P1 and P2 of the pressure chambers 24 and 25 are changed from the current pressures to the pressure command values P1_c and P2_c.

  According to the control device of the present embodiment described above, the induced voltage constant Ke is estimated based on the pressures P1 and P2 detected by the pressure sensors 28 and 29, respectively, and the rotational speed Nm of the output shaft 2 of the electric motor 1. Thus, the estimation can be performed appropriately. Then, using the estimated value of the induced voltage constant Ke, the command values Id_c and Iq_c of the energizing current of the electric motor 1 are determined and the energized current is controlled, so that the rotor corresponding to the actual induced voltage constant Ke is determined. It is possible to perform energization control of the electric motor 1 suitable for the composite field with the interphase difference.

  Further, the hydraulic control unit 58 makes the actual induced voltage constant Ke (the induced voltage constant Ke estimated by the Ke calculating unit 47) coincide with the command value Ke of the induced voltage constant determined by the Ke command calculating unit 49. Thus, the command values P1_c and P2_c for the pressures P1 and P2 of the pressure chambers 24 and 25 are determined, and the operation of the inter-rotor relative rotation means 23 is controlled by the command values P1_c and P2_c. In addition, it is possible to control the phase difference between the rotors to be suitable for satisfying the requirements regarding the energy efficiency of the electric motor 1.

  Furthermore, in the energization control of the electric motor 1, the field control unit 52 and the calculation unit 50 correct the d-axis current command value Id_c and manipulate the d-axis current, so that the actual phase difference between the rotors is an induced voltage constant. Until the phase difference between the rotors corresponding to the command value Ke_c is reached, the combined field with the actual phase difference between the rotors and the combined field with the phase difference between the rotors required by the pressure command values P1_c and P2_c. The deviation can be compensated by a field due to the d-axis current. As a result, the torque required for the phase difference between the rotors corresponding to the command value Ke_c of the induced voltage constant before the actual phase difference between the rotors reaches the phase difference between the rotors corresponding to the command value Ke_c of the induced voltage constant. The output shaft 2 of the electric motor 1 can be smoothly generated without any trouble, and the responsiveness of the electric motor 2 can be kept high.

  In the embodiment described above, the induced voltage constant Ke is used as the phase difference parameter and is estimated by the Ke calculating unit 47. Instead of the induced voltage constant Ke, the inter-rotor phase difference θd is set as the phase difference parameter. May be used. In this case, the estimated value of the inter-rotor phase difference θd obtained by the Ke calculating unit 47 as described above is input to the current command calculating unit 48, and the current command calculating unit 48 uses the current command value Id_c. , Iq_c, the inter-rotor phase difference θd may be used instead of Ke.

  Further, the Ke command calculation unit 49 converts this command value Ke_c into a command value of the inter-rotor phase difference θd according to the correlation data represented by the graph f shown in FIG. 7 instead of the command value Ke_c of the induced voltage constant. Then, a command value for the inter-rotor phase difference θd may be output. Alternatively, the command value for the inter-rotor phase difference θd may be directly determined and output from the torque command value Tc, the rotational speed Nm, and the power supply voltage Vdc using a map or the like. In such a case, the hydraulic pressure control unit 58 receives the command value of the inter-rotor phase difference, and the command value and the estimated value of the inter-rotor phase difference θd obtained by the Ke calculation unit 47 as described above. Enter the deviation. Then, in the hydraulic control unit 58, for example, the feedforward command value of the pressures P1 and P2 is determined from the input command value of the phase difference between the rotors as in the above-described embodiment, and this feedforward command value is determined. Is corrected according to the input deviation of the inter-rotor phase difference, and the operation command value for the pressure P1, P2 inter-rotor relative rotation means 23 may be determined.

  The hydraulic control unit 58 determines and outputs the command values P1_c and P2_c of the pressures P1 and P2 as the operation command values for the relative rotation means 23 between the rotors. A command value for θd may be determined and output. In this case, when Ke_c and ΔKe are input to the hydraulic pressure control unit 58, a value obtained by converting the command value Ke_c of the induced voltage constant into the inter-rotor phase difference θd according to the graph of FIG. It is only necessary to determine the command value of the inter-rotor phase difference θd for the inter-rotor relative rotation means 23 by performing correction according to the above. In addition, when the command value of the corresponding inter-rotor phase difference θd and the deviation of the inter-rotor phase difference are input to the hydraulic pressure control unit 58 instead of Ke_c and ΔKe, the input inter-rotor phase difference θd. The command value of the inter-rotor phase difference with respect to the inter-rotor relative rotation means 23 may be determined by correcting the command value according to the input deviation. When the hydraulic control unit 58 determines and outputs the command value for the phase difference between the rotors as described above, the relative rotation means 23 between the rotors uses the input command value for the phase difference between the rotors as described above. The pressures P1 and P2 may be determined based on the correlation data represented by the graphs c and d in FIG. 6, and the pressures P1 and P2 may be operated accordingly.

Sectional drawing of the principal part of the electric motor in one Embodiment of this invention. The figure which looked at the axial center direction of this electric motor in the state which removed the drive plate 19 of the electric motor of FIG. FIG. 3A is a diagram showing a phase relationship between the inner rotor and the outer rotor of the motor in the field strengthened state, and FIG. 3B is a diagram showing the relationship between the inner rotor and the outer rotor of the motor in the field weakened state. The figure which shows a phase relationship. The graph which shows the induced voltage of the armature of an electric motor in a field strengthening state and a field weakening state. The block diagram which shows the functional structure of the control apparatus of the electric motor of FIG. The figure for demonstrating the process of Ke calculation part 47 with which the control apparatus was equipped. The figure for demonstrating the process of Ke calculation part 47 with which the control apparatus was equipped. The figure for demonstrating the process of Ke calculation part 47 with which the control apparatus was equipped. The flowchart which shows the process of Ke calculation part 47 with which the control apparatus was equipped. The figure which shows the operating characteristic of the electric motor in a drive side and a regeneration side.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Electric motor, 2 ... Output shaft, 3 ... Outer rotor, 4 ... Inner rotor, 6 (6a, 6b) ... Permanent magnet of outer rotor, 8 (8a, 8b) ... Permanent magnet of inner rotor, 9 ... First member DESCRIPTION OF SYMBOLS 10 ... 2nd member, 11 ... Ring part of 2nd member, 12 ... Projection part of 2nd member, 13 ... Ring part (shaft part) of 2nd member, 14 ... Projection part of 2nd member, 23 ... Rotor Relative rotation means 24 ... first pressure chamber 25 ... second pressure chamber 28 ... pressure sensor (first pressure detection means) 29 ... pressure sensor (second pressure detection means) 46 ... differentiation calculation section (Rotational speed detection means), 47... Ke calculation section (phase difference parameter estimation means), 49... Ke command calculation section (phase difference parameter command value output means), 48, 50, 51, 52, 53, 54, 55, 56... Energization control means, 58... Hydraulic control unit (operation command value determination means), STEP 2. It means.

Claims (9)

An outer rotor having a plurality of permanent magnets arranged in the circumferential direction, an inner rotor having a plurality of permanent magnets arranged in the circumferential direction and provided coaxially with the outer rotor, and the outer rotor and the inner rotor. A relative rotation means between the rotors for rotating either one relative to the other around the axis of the two rotors, and changing the phase difference between the two rotors by the relative rotation between the outer rotor and the inner rotor. According to the control device of the electric motor that can change the synthetic field of the permanent magnets of both rotors,
The inter-rotor relative rotation means includes a first member provided integrally with the outer rotor so as to be rotatable relative to the inner rotor, and a first member provided integrally with the inner rotor so as to be rotatable relative to the outer rotor. Two members, and a pressure chamber constituted by the first member and the second member so that the volume changes in accordance with a change in phase difference between the two rotors. Is a means for causing relative rotation between the two rotors by operating with a working fluid supplied to the
Pressure detecting means for detecting the pressure in the pressure chamber;
Based on the pressure detected by the pressure detecting means, either the actual phase difference between the rotors or the characteristic parameter of the motor having a predetermined correlation with the phase difference is determined. A phase difference parameter estimating means for estimating a value of the phase difference parameter as a phase difference parameter;
An electric motor control device comprising: energization control means for performing energization control of the electric motor based on the value of the phase difference parameter estimated by the phase difference parameter estimation means. The pressure chamber includes a first pressure chamber that generates a pressure for rotating the inner rotor in a first direction relative to the outer rotor, and the first rotor in the first direction relative to the outer rotor. And a second pressure chamber that generates a pressure to rotate relative to the second direction opposite to the second direction,
The pressure detection means includes first pressure detection means and second pressure detection means for detecting respective pressures of the first pressure chamber and the second pressure chamber,
2. The electric motor according to claim 1, wherein the phase difference parameter estimation unit estimates a value of the phase difference parameter based on pressures respectively detected by the first pressure detection unit and the second pressure detection unit. Control device. The first member is provided coaxially with the outer rotor, and is provided with a shaft portion integrally provided with the outer rotor so as to be relatively rotatable with respect to the inner rotor, and projecting radially from the outer peripheral surface of the shaft portion. A plurality of first member side protrusions,
The second member includes an annular portion provided coaxially with the shaft portion of the first member and having the tip end portion of the first member-side protruding portion slidably contacted with an inner peripheral surface, and an inner peripheral surface of the annular portion. And a plurality of second members projecting at locations between the pair of first member side projections adjacent to each other in the circumferential direction of the shaft portion, and having their tip portions slidably contacted with the outer peripheral surface of the shaft portion. It is a member consisting of side protrusions,
A space between one of the pair of first member side projections adjacent to each other in the circumferential direction of the shaft portion and the second member side projection at a position between the pair of first member side projections Is configured as the first pressure chamber, and between the other of the first member side protrusions of the pair and the second member side protrusions present at a location between the first member side protrusions of the pair. The motor control device according to claim 2, wherein the space is configured as the second pressure chamber.   Rotational speed detecting means for detecting the rotational speed of an output shaft of an electric motor provided so as to be rotatable integrally with any one of the outer rotor and the inner rotor is provided, and the phase difference parameter estimating means includes the pressure detecting means The means for estimating the value of the phase difference parameter based on the pressure detected by the rotation speed and the rotation speed detected by the rotation speed detection means. The control apparatus of the electric motor of description.   The motor control device according to claim 1, wherein the characteristic parameter of the electric motor is an induced voltage constant of the electric motor.   The phase difference parameter command value output means for outputting the command value of the phase difference parameter, and the operation of the inter-rotor relative rotation means according to the deviation between the command value of the phase parameter and the estimated value of the phase difference parameter 6. An operation command value determining means for determining a command value, wherein the inter-rotor relative rotation means operates the pressure in the pressure chamber according to the operation command value. The control apparatus for the electric motor according to item 1.   The operation command value is a command value of the pressure of the pressure chamber, and the energization control unit is configured to energize the electric motor according to a deviation between the command value of the pressure and the pressure detected by the pressure detection unit. The electric motor control device according to claim 6, further comprising means for operating current.   The operation command value is a command value of the phase difference between the two rotors, and the energization control means corresponds to the command value of the phase difference and the value of the phase difference parameter estimated by the phase difference parameter estimation means. The motor control device according to claim 6, further comprising means for operating an energization current of the motor in accordance with a deviation from a phase difference value between the rotors.   9. The electric motor according to claim 1, further comprising an abnormality detection unit that determines whether or not the rotor relative rotation unit is abnormal based on the pressure detected by the pressure detection unit. Control device.

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