JP5212696B2 - Electric motor control device - Google Patents

Description

  The present invention relates to a motor control device that performs field weakening control of a permanent magnet field motor by changing the relative displacement angles of two rotors provided concentrically around a rotation shaft.

  A first rotor and a second rotor are provided concentrically around the rotating shaft of a permanent magnet field-type rotary motor, and the field is changed by changing the phase difference between the first rotor and the second rotor according to the rotational speed. An electric motor that performs magnetic field weakening control is known (see, for example, Patent Document 1).

  FIG. 12 is a cross-sectional view of an electric motor including a double rotor. In the electric motor 1 shown in FIG. 12, the inner rotor 11 in which the fields of the permanent magnets 11a and 11b are arranged at equal intervals along the circumferential direction, and the field of the permanent magnets 12a and 12b are at equal intervals along the circumferential direction. And the stator 10 having the armature 10a for generating a rotating magnetic field for the inner rotor 11 and the outer rotor 12.

  The inner rotor 11 and the outer rotor 12 are both arranged concentrically so that the rotating shaft is coaxial with the rotating shaft 2 of the electric motor 1. In the inner rotor 11, permanent magnets 11 a having the N pole as the rotating shaft 2 side and permanent magnets 11 b having the S pole as the rotating shaft 2 side are alternately arranged. Similarly, in the outer rotor 12, permanent magnets 12 a having the N pole as the rotating shaft 2 side and permanent magnets 12 b having the S pole as the rotating shaft 2 side are alternately arranged.

  The phase difference between the outer rotor 12 and the inner rotor 11 (hereinafter referred to as “rotor phase difference”) can be changed to the advance side or the retard side at least in the range of 180 degrees in electrical angle. For this reason, the state of the electric motor 1 includes a field-enhanced state in which the permanent magnets 12a and 12b of the outer rotor 12 and the permanent magnets 11a and 11b of the inner rotor 11 are arranged opposite to each other, and a permanent state of the outer rotor 12. It can be set as appropriate between the magnets 12a, 12b and the field weakening state in which the permanent magnets 11a, 11b of the inner rotor 11 are arranged with the same poles facing each other.

  The rotor phase difference is changed by a rotor phase difference changing unit provided inside the electric motor 1. FIG. 13 is a diagram illustrating an internal structure of a rotor phase difference changing unit included in the electric motor 1. As shown in FIG. 13, the rotor phase difference changing unit 30 is a single pinion type planetary gear mechanism disposed in the hollow portion on the inner peripheral side of the inner rotor 11, and is formed coaxially and integrally with the outer rotor 12. The first ring gear R1, the second ring gear R2 that is coaxially and integrally formed with the inner rotor 11, the first planetary gear 31 that meshes with the first ring gear R1, and the second planetary gear 32 that meshes with the second ring gear R2. The first planetary carrier C1 rotatably supports the sun gear S and the first planetary gear 31 that are engaged with the first planetary gear 31 and the second planetary gear 32. , And a second planetary carrier C2 that rotatably supports the second planetary gear 32 and is fixed to the stator 10.

  The first ring gear R1 and the second ring gear R2 have substantially the same gear shape, and the first planetary gear 31 and the second planetary gear 32 also have substantially the same gear shape. The rotating shaft 33 of the sun gear S is disposed coaxially with the rotating shaft 2 of the electric motor 1 and is rotatably supported by a bearing 34. For this reason, the 1st planetary gear 31 and the 2nd planetary gear 32 mesh with the sun gear S, and the outer side rotor 12 and the inner side rotor 11 rotate in synchronization. Further, the rotation shaft 35 of the first planetary carrier C1 is disposed coaxially with the rotation shaft 2 of the electric motor 1 and is connected to the actuator 25, and the second planetary carrier C2 is fixed to the stator 10.

  The actuator 25 rotates the first planetary carrier C1 in the normal rotation direction or the reverse rotation direction by hydraulic pressure according to a control signal input from the phase difference control system of the control device, or the first planetary carrier C1 around the rotation axis 2. Regulate the rotation of When the first planetary carrier C1 is rotated by the actuator 25, the relative positional relationship (phase difference) between the outer rotor 12 and the inner rotor 11 changes.

  FIG. 14 is a diagram showing a field strengthening state (a) and a field weakening state (b) of the electric motor 1. In the field-strengthened state shown in FIG. 14A, the direction of the magnetic flux Q2 of the permanent magnets 12a and 12b of the outer rotor 12 and the magnetic flux Q1 of the permanent magnets 11a and 11b of the inner rotor 11 is the same. Q3 is large. On the other hand, in the field weakening state shown in FIG. 14B, the directions of the magnetic flux Q2 of the permanent magnets 12a and 12b of the outer rotor 12 and the magnetic flux Q1 of the permanent magnets 11a and 11b of the inner rotor 11 are reversed. The magnetic flux Q3 is small.

  As described above, in the electric motor 1 including the double rotor, the induced voltage constant Ke can be changed by changing the rotor phase difference to increase or decrease the magnetic flux of the field. FIG. 15 is a diagram showing an operable region according to the rotation speed and torque of the electric motor 1 that changes according to the induced voltage constant Ke. As shown in FIG. 15, when the rotor phase difference is small and the induced voltage constant Ke is large (field strong state), the operable speed of the electric motor 1 decreases, but a large torque can be output. On the other hand, when the rotor phase difference is large and the induced voltage constant Ke is small (field weakening state), the torque that can be output from the electric motor 1 is reduced, but operation is possible up to a high rotational speed. As described above, the operable range of the electric motor 1 with respect to the rotation speed and the torque changes according to the induced voltage constant Ke.

  As described above, when the rotor phase difference is changed, the induced voltage constant Ke of the electric motor 1 changes, and the operable region of the electric motor 1 changes as shown in FIG. For this reason, the rotor phase difference in which the operating range of the electric motor 1 and the operating efficiency of the electric motor 1 are optimal can be expressed as shown in FIG. Conventionally, the phase difference control system included in the control device of the electric motor 1 controls the rotor phase difference based on the graph shown in FIG. 16 so that the operation efficiency of the electric motor 1 is maximized.

JP 2002-204541 A JP 2007-159219 A JP 2007-259549 A

  The control device for the electric motor 1 using the graph shown in FIG. 16 controls the rotor phase difference so that the operating efficiency of the electric motor 1 is maximized according to the requested torque value and the rotational speed of the electric motor 1. As described above, the rotor phase difference changes when the actuator 25 is mechanically operated by the control signal from the control device and the rotor phase difference changing unit 30 provided in the electric motor 1 functions. Therefore, for example, when the maximum torque value is requested when the rotor phase difference is 100 ° and the torque is low, the control device controls the rotor phase difference to change from 100 ° to 0 °. However, since the actuator 25 and the rotor phase difference changing unit 30 are mechanically operated by hydraulic pressure or the like, it takes, for example, about 1 second until the rotor phase difference is delayed by 100 °.

  When the electric motor 1 is used as a vehicle drive source, there is no particular problem even if the time required for the advance or delay of the rotor phase difference is in seconds as long as the vehicle is in a regenerative braking state. However, if it takes 1 second to adjust the rotor phase difference when a rapid acceleration operation or the like is performed by the driver, a satisfactory result may not be obtained as a running performance of the vehicle.

  An object of the present invention is to provide an electric motor control device that can output a required torque without being affected by the operation time of a means for adjusting the relative displacement angle of two rotors of the electric motor. is there.

In order to solve the above-described problems and achieve the object, an electric motor control device according to a first aspect of the present invention is a rotating shaft (for example, electric motor 1 in the embodiment) of a permanent magnet field type electric motor. For example, a first rotor (for example, outer rotor 12 in the embodiment) and a second rotor (for example, inner side in the embodiment) provided concentrically around the rotation shaft 2) in the embodiment. A control device for an electric motor that controls a relative displacement angle of the rotor (11) (for example, a rotor phase difference in the embodiment), and detects the number of rotations per unit time of the first rotor or the second rotor. Detected by the rotation speed detection unit (for example, the resolver 101 and the rotation speed calculation unit 103 in the embodiment), the requested torque value (for example, the torque command value T in the embodiment), and the rotation speed detection unit Number of revolutions (eg, implementation form On the basis of the rotational speed Nm) of the first and second rotors of the electric motor (for example, the rotor phase difference command value θc in the embodiment) or the relative displacement angle. A command value determining unit (for example, command value determining units 121 and 321 in the embodiment) for determining a command value of a variable to be correlated (for example, a command value θc of the induced voltage constant Ke_c in the embodiment), and the command A control unit that controls the relative displacement angles of the first rotor and the second rotor of the electric motor according to the command value determined by the value determination unit (for example, the rotor phase difference control unit 123 in the embodiment). , 323), and the command value determining unit on the graph showing the relationship between the torque and the rotational speed of the motor, the orthogonal region where the field weakening control is not required for the motor (for example, implementation) orthogonal region X) in the form, the In a region where the operating efficiency of the motor is better when the counter displacement angle is advanced than the relative displacement angle at which the induced voltage of the motor at the rotational speed is maximum, the induced voltage of the motor at the rotational speed is maximum. An intermediate value between the relative displacement angle and the relative displacement angle with the best operating efficiency of the motor is determined as the command value.

Furthermore, in the motor control device according to claim 2 , the command value determination unit is configured such that the relative displacement angle within the orthogonal region is a relative displacement angle at which an induced voltage of the motor is maximized at the rotation speed. In a region where the operation efficiency of the electric motor is better when advanced, the relative displacement at which the induced voltage of the electric motor at the rotation speed becomes maximum instead of the determination by the command value determination unit according to claim 1. An intermediate value between a variable correlated with an angle and a variable correlated with a relative displacement angle with the best operating efficiency of the electric motor is determined as the command value.

Furthermore, in the motor control device according to the third aspect of the present invention, the rotating shaft (for example, the rotating shaft 2 in the embodiment) of the permanent magnet field motor (for example, the motor 1 in the embodiment) is provided. Relative displacement angles (for example, implementation) of a first rotor (for example, outer rotor 12 in the embodiment) and a second rotor (for example, inner rotor 11 in the embodiment) provided concentrically around the circumference. a control unit for an electric motor for controlling the rotor phase difference) in the form, the rotation speed detector which detects the number of revolutions per unit time of the first rotor or the second rotor (e.g., in the embodiment Resolver 101 and rotation speed calculation unit 103), requested torque value (for example, torque command value T in the embodiment) and rotation speed detected by the rotation speed detection unit (for example, in the embodiment) Based on the rotational speed Nm) Relative displacement angle of the first rotor and the second rotor of the motive (for example, the command value θc of the rotor phase difference in the embodiment) or a variable correlated with the relative displacement angle (for example, in the embodiment A command value determining unit (for example, command value determining units 221 and 321 in the embodiment) for determining a command value of the induced voltage constant Ke_c), and a command value determined by the command value determining unit A control unit (for example, rotor phase difference control unit 223, 323 in the embodiment) for controlling the relative displacement angle of the first rotor and the second rotor of the electric motor, and the command value The determination unit includes an orthogonal region (for example, an orthogonal region X in the embodiment) that does not require field weakening control on the electric motor on the graph indicating the relationship between the torque and the rotational speed of the electric motor, and the electric motor. Where field weakening control is required The induced voltage generated when the motor is driven in a state where the induced voltage of the motor is fixed at a relative displacement angle at which the maximum is maximized, from the rotation speed exceeding the withstand voltage of the motor or the electronic component related to the motor. In a specific region (e.g., region Z in the embodiment) that is less than a predetermined rotational speed, the relative displacement angle at which the induced voltage of the electric motor at the rotational speed is maximum or a variable related to the relative displacement angle is It is characterized by being determined as a command value.

Furthermore, in the motor control device of the invention according to claim 4 , the command value determining unit is configured to determine that the induced voltage of the motor at the rotational speed is the maximum in the relative displacement angle in the orthogonal region and the specific region. In an area where the operating efficiency of the electric motor is better when the angle is advanced than the relative displacement angle, the induced voltage of the electric motor at the rotational speed is the maximum instead of the determination by the command value determining unit according to claim 3. An intermediate value between the relative displacement angle and the relative displacement angle with the best operating efficiency of the motor is determined as the command value.

Furthermore, in the motor control device of the invention according to claim 5 , the command value determination unit is configured to determine that the induced voltage of the motor at the rotational speed is the maximum in the relative displacement angle in the orthogonal region and the specific region. In an area where the operating efficiency of the electric motor is better when the angle is advanced than the relative displacement angle, the induced voltage of the electric motor at the rotational speed is the maximum instead of the determination by the command value determining unit according to claim 3. An intermediate value between a variable that correlates with the relative displacement angle and a variable that correlates with the relative displacement angle with the best operating efficiency of the motor is determined as the command value.

Furthermore, in the motor control device according to the sixth aspect of the present invention, the rotating shaft (for example, the rotating shaft 2 in the embodiment) of the permanent magnet field motor (for example, the motor 1 in the embodiment) is provided. Relative displacement angles (for example, implementation) of a first rotor (for example, outer rotor 12 in the embodiment) and a second rotor (for example, inner rotor 11 in the embodiment) provided concentrically around the circumference. a control unit for an electric motor for controlling the rotor phase difference) in the form, the rotation speed detector which detects the number of revolutions per unit time of the first rotor or the second rotor (e.g., in the embodiment Resolver 101 and rotation speed calculation unit 103), requested torque value (for example, torque command value T in the embodiment) and rotation speed detected by the rotation speed detection unit (for example, in the embodiment) Based on the rotational speed Nm) Relative displacement angle of the first rotor and the second rotor of the motive (for example, the command value θc of the rotor phase difference in the embodiment) or a variable correlated with the relative displacement angle (for example, in the embodiment A command value determining unit (for example, command value determining units 121, 221 and 321 in the embodiment) for determining a command value of the induced voltage constant Ke_c), and a command value determined by the command value determining unit And a control unit (for example, rotor phase difference control units 123, 223, and 323 in the embodiment) that controls relative displacement angles of the first rotor and the second rotor of the electric motor. The command value determining unit, on a graph showing the relationship between the torque of the motor and the rotational speed, a relative displacement angle at which the induced voltage of the motor at the rotational speed is maximum or a variable related to the relative displacement angle. As the command value The region to be determined is an orthogonal region (for example, the orthogonal region X in the embodiment) that does not require field weakening control for the electric motor, or a field for the electric motor, depending on the operating state of the electric motor. The induced voltage generated when the motor is driven in a state where the induced voltage of the motor is fixed at a relative displacement angle at which the induced voltage of the motor is maximum is within a region where weak control is necessary. It is characterized in that it is set in a specific region (for example, region Z in the embodiment) which is lower than a predetermined rotational speed lower than the rotational speed exceeding the withstand voltage and the orthogonal region.

According to the motor control device of the first to sixth aspects of the present invention, the operation efficiency is somewhat sacrificed, but the rotor phase difference is not changed even when the maximum torque is suddenly requested. As a result, the electric motor can output the required torque without being affected by the operation time of the means for adjusting the relative displacement angle of the two rotors.

In addition, according to the control device for an electric motor of the invention according to claim 1 , 2 , 4, or 5 , even if the maximum torque is suddenly requested while maintaining the driving efficiency in a better state, The required torque can be output without being greatly affected by the operation time of the means for adjusting the relative displacement angle of the rotor.

According to the electric motor control apparatus of the sixth aspect of the invention, it is possible to change the characteristics of the torque output according to the optimum operating efficiency and the sudden maximum torque request according to the operating state of the electric motor.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  The electric motors used in the embodiments described below are the same as the permanent magnet field motor 1 shown in FIGS. 12 and 13, and the inner rotor 11 and the outer rotor 12 provided concentrically around the rotating shaft 2. And a stator 10 having an armature 10a and a rotor phase difference changing unit 30. The electric motor is used as, for example, a drive source of a hybrid vehicle or an electric vehicle, and operates as an electric motor and a generator when mounted on the hybrid vehicle. Further, the control device for the electric motor 1 (hereinafter simply referred to as “control device”) corresponds to a current control system for controlling the current supplied to the electric motor 1 based on the torque command value and the like, the torque command value and the rotational speed, and the like. And a phase difference control system for controlling the phase difference of the double rotor of the electric motor 1.

(First embodiment)
FIG. 1 is a block diagram showing a control device for an electric motor 1 according to a first embodiment of the present invention. As shown in FIG. 1, the control device of the first embodiment includes a resolver 101, a rotation speed calculation unit 103, a current command calculation unit 105 included in a current control system, a bandpass filter (BPF) 107, and a three-phase. -Dp conversion unit 109, current FB control unit 111, rθ conversion unit 113, PWM calculation unit 115, actuator 25 described above, Ke calculation unit 119, command value determination unit 121 and rotor included in the phase difference control system And a phase difference control unit 123.

  The resolver 101 detects the mechanical angle of the outer rotor 12 and outputs an electrical angle θm corresponding to the detected mechanical angle. The electrical angle θm output from the resolver 101 is sent to the three-phase-dq converter 109 and the rotation speed calculator 103. The rotational speed calculation unit 103 calculates the angular speed ω of the outer rotor 12 and the rotational speed Nm per unit time of the outer rotor 12 from the electrical angle θm input from the resolver 101. The rotation speed Nm calculated by the rotation speed calculation unit 103 is sent to the current command calculation unit 105 and the command value determination unit 121. Further, the angular velocity ω calculated by the rotation speed calculation unit 103 is sent to the Ke calculation unit 119.

  The current command calculation unit 105 is based on the torque command value T input from the outside, the rotation number Nm of the motor 1 calculated by the rotation number calculation unit 103, and the induced voltage constant Ke calculated by the Ke calculation unit 119. The command value Id_c of the current (hereinafter referred to as “d-axis current”) flowing through the d-axis side armature (hereinafter referred to as “d-axis armature”) and the q-axis side armature (hereinafter referred to as “q-axis armature”). The command value Iq_c of the current (hereinafter referred to as “q-axis current”) to be passed through is determined.

  The three-phase-dq converter 109 is based on the current detection signals Iu and Iw detected by the current sensors 131 and 133 and unnecessary components removed by the BPF 107, and the electrical angle θm of the outer rotor 12 detected by the resolver 73. Three-phase-dq conversion is performed to calculate a detected value Id_s of the d-axis current and a detected value Iq_s of the q-axis current.

  The current FB control unit 111 is configured to reduce the deviation ΔId between the d-axis current command value Id_c and the detection value Id_s and the deviation between the q-axis current command value Iq_c and the detection value Iq_s ΔIq. Hereinafter, a command value Vd_c of “d-axis voltage”) and a command value Vq_c of a terminal voltage of the q-axis armature (hereinafter referred to as “q-axis voltage”) are determined. The deviation ΔId is controlled by the field controller 141. The deviation ΔIq is controlled by the power control unit 143.

  The rθ converter 113 converts the d-axis voltage command value Vd_c and the q-axis voltage command value Vq_c into components of magnitude V1 and angle θ. The PWM calculation unit 115 converts the component of the magnitude V1 and the angle θ into a three-phase (U, V, W) AC voltage by PWM control.

The Ke calculator 119 calculates an induced voltage constant Ke from the following formula (1).
Ke = (Vq−ω · Ld · Id−R · Iq) / ω (1)
(Ω: angular velocity of motor 1, R: resistance of q-axis armature and d-axis armature, Iq: q-axis current, Vq: voltage between terminals of q-axis armature, Ld: inductance of d-axis armature, Id: d-axis current)

  The command value determination unit 121 is based on the torque command value T input from the outside, the rotation speed Nm of the electric motor 1 calculated by the rotation speed calculation unit 103, and the battery voltage Vdc of a capacitor (not shown) input from the outside. Thus, the command value Ke_c of the induced voltage constant is determined. The command value determination unit 121 uses the first Ke map shown in FIG. 2 stored in a memory (not shown) when determining the command value Ke_c of the induced voltage constant. The first Ke map is created in advance based on the graph shown in FIG. 3 and stored in the memory. FIG. 3 is a graph showing the relationship between the rotational speed Nm and the torque of the electric motor 1 and the induced voltage constant set in the first embodiment.

  FIG. 4 is a graph showing a region where the field weakening control of the electric motor 1 is necessary. Similar to FIG. 3, the vertical axis of the graph represents torque, and the horizontal axis represents the rotational speed Nm. In addition, the symbol u in the figure is an orthogonal line of the electric motor 1 (when the electric motor 1 is operated without performing field weakening control, the phase voltage of the electric motor 1 is equal to the power supply voltage by the combination of the rotational speed Nm and the torque. Line connecting the points. Symbol X indicates a region (orthogonal region) that does not require field weakening control, and symbol Y indicates a region (non-orthogonal region) that requires field weakening control.

  In the present embodiment, the command value determination unit 121 sets the induced voltage constant to the maximum in the orthogonal region X, and appropriately sets the induced voltage constant in the non-orthogonal region Y according to the relationship between the rotational speed Nm and the torque. In the example shown in FIG. 3, when the induced voltage constant has a relationship of Ke1> Ke2> Ke3> Ke4> Ke5, the induced voltage constant Ke1 is set in the orthogonal region X, and in the non-orthogonal region Y, depending on the relationship with the torque. Appropriate induced voltage constants (Ke1 to Ke5) are appropriately set.

  Note that the relationship between the rotation speed and torque of the electric motor 1 changes according to the battery voltage Vdc of the battery. Therefore, the first Ke map is provided with a plurality of tables that differ depending on the battery voltage Vdc. For example, as shown in FIG. 2, a plurality of tables such as a table used when the battery voltage Vdc is about V1 and a table used when the battery voltage Vdc is about V2 are provided in the first Ke map.

  As shown in FIG. 5, the command value determination unit 121 uses the first Ke map of the table corresponding to the battery voltage Vdc input from the outside, and generates an induced voltage constant Ke corresponding to the torque command value T and the rotational speed Nm. Then, the command value ke_c of the induced voltage constant is output.

  The rotor phase difference control unit 123 outputs a control signal such that the deviation ΔKe between the command value Ke_c of the induced voltage constant output from the command value determination unit 121 and the induced voltage constant Ke calculated by the Ke calculation unit 119 is reduced, The actuator 25 is controlled. When the rotor phase difference is changed by the actuator 25, the magnetic flux of the field changes, so that the induced voltage constant Ke of the electric motor 1 also changes.

  As described above, according to the control device of the present embodiment, in the orthogonal region X, the induced voltage constant is set to the maximum regardless of the required torque value T and the rotational speed Nm, so the rotor position of the electric motor 1 is The phase difference is kept constant, and in the non-orthogonal region Y, the rotor phase difference is adjusted according to the torque value T and the rotational speed Nm required to maximize the operating efficiency of the electric motor 1 as in the conventional case. Therefore, in the orthogonal region X, the driving efficiency is somewhat sacrificed, but the rotor phase difference is not changed even when a rapid acceleration operation or the like is performed by the driver. As a result, the electric motor 1 can output the required torque without being affected by the operating time of the actuator 25 and the rotor phase difference changing unit 30 when the rotor phase difference is advanced or retarded.

  The command value determination unit 121 may set the induced voltage constant to a value not less than about Ke1 and not more than about half of Ke2 in the orthogonal region X. That is, as shown in the graph of FIG. 16, the orthogonal region X includes a region where the operating efficiency of the electric motor 1 is better when the rotor phase difference is advanced by 100 ° to 120 °. In the above description, the rotor phase difference is not advanced even in this region, that is, the induced voltage constant is kept constant. However, the rotor phase difference may be advanced by about 50 ° to 60 °.

(Second Embodiment)
Similarly to the first command value determination unit 121, the command value determination unit 221 of the second embodiment and the torque command value T input from the outside and the rotation speed of the electric motor 1 calculated by the rotation speed calculation unit 103. A command value Ke_c of the induced voltage constant is determined based on Nm and a battery voltage Vdc of a capacitor (not shown) input from the outside. However, the command value determination unit 221 uses the second Ke map shown in FIG. 6 stored in a memory (not shown) when determining the command value Ke_c of the induced voltage constant. The second Ke map is created in advance based on the graph shown in FIG. 7 and stored in the memory. FIG. 7 is a graph showing the relationship between the rotational speed Nm and the torque of the electric motor 1 and the induced voltage constant set in the second embodiment.

  In the present embodiment, the command value determining unit 221 sets the induced voltage constant to the maximum in the region Z equal to or less than the rotation speed indicated by the dotted line v in FIG. In the region other than the region Z of Y, the induced voltage constant is appropriately set according to the relationship between the rotational speed Nm and the torque. In the example shown in FIG. 7, when the induced voltage constant has a relationship of Ke1 >> Ke4> Ke5, the orthogonal region X and the region Z are set to the induced voltage constant Ke1 and the regions other than the region Z of the non-orthogonal region Y Then, an appropriate induced voltage constant (Ke4 or Ke5) is appropriately set according to the relationship with the torque.

  The rotational speed indicated by the dotted line v in FIG. 7 is the induced voltage generated in the motor 1 when the motor 1 is driven in a state where the maximum induced voltage constant Ke1 is set, that is, in a state where the rotor phase difference is fixed at 0 °. The number of rotations is lower than the number of rotations when (= induced voltage constant × number of rotations) exceeds the breakdown voltage of the switching element of the inverter connected to the electric motor 1.

  Note that the second Ke map also includes a plurality of different tables depending on the battery voltage Vdc, as in the first Ke map described in the first embodiment. For example, as shown in FIG. 6, a plurality of tables such as a table used when the battery voltage Vdc is about V1 and a table used when the battery voltage Vdc is about V2 are provided in the second Ke map.

  The command value determination unit 221 determines an induced voltage constant Ke corresponding to the torque command value T and the rotational speed Nm using the second Ke map of the table corresponding to the battery voltage Vdc input from the outside, and the induced voltage constant Command value ke_c is output.

  Thus, in the present embodiment, the induced voltage constant is set to the maximum even in a part of the region Z of the non-orthogonal region Y that requires field weakening control. However, if the induced voltage constant is set to the maximum in the region Z, that is, if the rotor phase difference is fixed at 0 °, the operating efficiency of the electric motor 1 is lowered. Therefore, in the control device of the present embodiment, in the region Z, the phase difference control system sets the induced voltage constant to the maximum, but the current control system that controls the current supplied to the motor 1 supplies the field weakening current to the motor 1. Energize.

  The command value determination unit 221 may set the induced voltage constant to a value not less than Ke1 and not more than about half of Ke2, Ke3, or Ke4 in the orthogonal region X and the region Z. That is, as shown in the graph of FIG. 16, in the orthogonal region X, there is a region where the operating efficiency of the electric motor 1 is better when the rotor phase difference is advanced by 100 ° to 120 °. There is a region where the operating efficiency of the electric motor 1 is better when the angle is advanced by 150 °. In the above description, the rotor phase difference is not advanced even in this region, that is, the induced voltage constant is kept constant. However, the rotor phase difference may be advanced by about 50 ° to 75 °.

  The control device according to the present embodiment is the same as the control device according to the first embodiment, except for the energization of the field weakening current by the command value determination unit 221 and the current control system described above. Description is omitted.

  As described above, according to the control device of the present embodiment, in the partial region Z of the orthogonal region X and the non-orthogonal region Y, the induced voltage constant is maximum regardless of the required torque value T and the rotational speed Nm. Therefore, the rotor phase difference of the electric motor 1 is kept constant, and the torque value required to maximize the operating efficiency of the electric motor 1 in the region excluding the region Z of the non-orthogonal region Y is the same as in the past. The rotor phase difference is adjusted according to T and the rotational speed Nm. Therefore, in the orthogonal region X and the region Z, the driving efficiency is sacrificed, but the rotor phase difference is not changed even when a rapid acceleration operation or the like is performed by the driver. As a result, the electric motor 1 can output the required torque without being affected by the operating time of the actuator 25 and the rotor phase difference changing unit 30 when the rotor phase difference is advanced or retarded.

  In the above-described embodiment, the command value determination unit 121 uses the first Ke map and the command value determination unit 221 uses the second Ke map. However, the command value determination units 121 and 221 are operating states of the electric motor 1. Accordingly, any one of the Ke map, the first Ke map, and the second Ke map based on the graph shown in FIG. 16 may be selected and the selected Ke map may be used.

  In the first embodiment and the second embodiment described above, the command value determination units 121 and 221 determine the induced voltage constant according to the requested torque value T and the rotational speed Nm, and the rotor phase difference The control unit 123 outputs a control signal to the actuator 25 so that the deviation ΔKe between the command value Ke_c of the induced voltage constant output from the command value determination units 121 and 221 and the induced voltage constant Ke calculated by the Ke calculation unit 119 decreases. doing. As another embodiment, as shown in FIG. 8, a command value determining unit 321 may be provided instead of the command value determining units 121 and 221, and a rotor phase difference control unit 323 may be provided instead of the rotor phase difference control unit 123. good.

  The command value determination unit 321 is based on the torque command value T input from the outside, the rotation speed Nm of the electric motor 1 calculated by the rotation speed calculation unit 103, and the battery voltage Vdc of a capacitor (not shown) input from the outside. Thus, the rotor phase difference command value θc is determined. The command value determining unit 321 uses the θ map shown in FIG. 9 stored in a memory (not shown) when determining the rotor phase difference command value θc. The θ map is created in advance based on the graph shown in FIG. 3 or 7 and stored in the memory. In the θ map, an angle given in parentheses to each induced voltage constant Ke in FIGS. 3 and 7 is set as a rotor phase difference.

  The rotor phase difference control unit 323 controls the rotor phase difference command value θc output from the command value determination unit 321 and the control signal so that the deviation Δθ between the actual rotor phase difference θs detected by the rotor phase difference detection unit 117 decreases. And the actuator 25 is controlled.

  Further, instead of the Ke calculation unit 119 that calculates the induced voltage constant Ke based on the equation (1) described in the first embodiment, the induction is performed from the actual rotor phase difference θs obtained by the rotor phase difference detection unit 117. A Ke calculator 319 for calculating the voltage localization number Ke may be provided.

  Furthermore, although the said embodiment demonstrated the case where the requested | required torque command value T was power running torque, it is applicable similarly also in the case of regenerative torque. FIG. 10 shows a modification of the graph showing the relationship between the rotational speed Nm of the electric motor 1 and the power running torque or the regenerative torque and the set induced voltage constant. FIG. 11 shows a modification of the first Ke map applicable to both the power running torque and the regenerative torque.

The block diagram which shows the control apparatus of the electric motor 1 of 1st Embodiment or 2nd Embodiment which concerns on this invention The figure which shows the 1st Ke map used with the control apparatus of 1st Embodiment. The graph which shows the relationship between the rotation speed Nm of the electric motor 1, and a torque, and the induced voltage constant set in 1st Embodiment. The graph which shows the area | region where the field weakening control of the electric motor 1 is required The flowchart which shows operation | movement of the command value determination part 121 with which the control apparatus of 1st Embodiment is provided. The figure which shows the 2nd Ke map used with the control apparatus of 2nd Embodiment. The graph which shows the relationship between the rotation speed Nm of the electric motor 1, and a torque and the induced voltage constant set in 2nd Embodiment. The block diagram which shows the control apparatus of the electric motor 1 of other embodiment which concerns on this invention. The figure which shows (theta) map used with the control apparatus of other embodiment. The graph which shows the relationship between the rotation speed Nm of the electric motor 1, power running torque, or regenerative torque, and the induced voltage constant set. The figure which shows the modification of the 1st Ke map applicable to both power running torque and regenerative torque. Cross section of electric motor with double rotor The figure which shows the internal structure of the rotor phase difference change part which the electric motor 1 has The figure which shows the field strengthening state (a) and the field weakening state (b) of the electric motor 1 The figure which shows the driveable area | region according to the rotation speed and torque of the electric motor 1 which changes according to the induced voltage constant Ke. The graph which shows the relationship between the rotation speed Nm of the electric motor 1, and a torque, and the induced voltage constant set conventionally.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electric motor 2 Rotating shaft 11 Inner rotor 12 Outer rotor 10a Armature 10 Stator 30 Rotor phase difference change part R1 1st ring gear R2 2nd ring gear 31 1st planetary gear 32 2nd planetary gear 33, 35 Rotating shaft 34 Bearing S Sun gear C1 1st planetary carrier C2 2nd planetary carrier 101 Resolver 103 Rotation speed calculation part 105 Current command calculation part 107 Band pass filter (BPF)
109 3-phase-dp conversion unit 111 Current FB control unit 113 rθ conversion unit 115 PWM calculation unit 25 Actuator 117 Rotor phase difference detection unit 119, 319 Ke calculation units 121, 221 and 321 Command value determination unit 123, 323 Rotor phase difference control Part

Claims (6)

A control device for an electric motor for controlling a relative displacement angle between a first rotor and a second rotor provided concentrically around a rotation shaft of a permanent magnet field motor,
A rotational speed detector for detecting the rotational speed per unit time of the first rotor or the second rotor;
Based on the requested torque value and the rotational speed detected by the rotational speed detection unit, the relative displacement angle of the first rotor and the second rotor of the electric motor or a variable command correlated with the relative displacement angle A command value determining unit for determining a value;
A control unit that controls a relative displacement angle of the first rotor and the second rotor of the electric motor according to the command value determined by the command value determination unit;
The command value determining unit
On the graph showing the relationship between the torque of the motor and the number of revolutions, in the orthogonal region where field weakening control is not required for the motor , the relative displacement angle is the maximum induced voltage of the motor at the number of revolutions. In the region where the operating efficiency of the motor is better than the relative displacement angle, the relative displacement angle at which the induced voltage of the motor at the rotational speed is maximum and the relative displacement angle at which the operating efficiency of the motor is the best An intermediate value of the motor is determined as the command value. The motor control device according to claim 1,
The command value determining unit
2. The region according to claim 1, wherein the operating efficiency of the electric motor is better when the relative displacement angle in the orthogonal region is advanced than the relative displacement angle at which the induced voltage of the electric motor at the rotational speed is maximum. Instead of the determination by the command value determination unit , the intermediate between the variable correlated with the relative displacement angle at which the induced voltage of the electric motor at the rotational speed is maximum and the variable correlated with the relative displacement angle at which the operating efficiency of the electric motor is the best Is determined as the command value. A control device for an electric motor for controlling a relative displacement angle between a first rotor and a second rotor provided concentrically around a rotation shaft of a permanent magnet field motor,
A rotation speed detector which detects the number of revolutions per unit time of the first rotor or the second rotor,
Based on the requested torque value and the rotational speed detected by the rotational speed detection unit, the relative displacement angle of the first rotor and the second rotor of the electric motor or a variable command correlated with the relative displacement angle A command value determining unit for determining a value;
A control unit that controls a relative displacement angle of the first rotor and the second rotor of the electric motor according to the command value determined by the command value determination unit;
The command value determining unit
On the graph showing the relationship between the torque and the rotational speed of the motor, the motor in an orthogonal region where field weakening control is not required for the motor and in a region where field weakening control is required for the motor A predetermined rotational speed at which the induced voltage generated when the electric motor is driven with the relative displacement angle at which the induced voltage of the electric motor is fixed is lower than the rotational speed exceeding the withstand voltage of the electric motor or the electronic component related to the electric motor. In the following specific region, the relative displacement angle at which the induced voltage of the electric motor at the rotational speed becomes maximum or a variable related to the relative displacement angle is determined as the command value. The motor control device according to claim 3 ,
The command value determining unit
Wherein the orthogonal region and the specific region, in the operating efficiency is good area towards the induced voltage of the motor to the relative angular displacement in the rotational speed was advanced from the relative displacement angle that maximizes said motor, wherein Instead of the determination by the command value determination unit according to Item 3, an intermediate value between a relative displacement angle at which the induced voltage of the electric motor at the rotational speed is maximum and a relative displacement angle at which the operating efficiency of the electric motor is the best is A control device for an electric motor, wherein the control device determines the command value. The motor control device according to claim 3 ,
The command value determining unit
Wherein the orthogonal region and the specific region, in the operating efficiency is good area towards the induced voltage of the motor to the relative angular displacement in the rotational speed was advanced from the relative displacement angle that maximizes said motor, wherein Instead of the determination by the command value determination unit according to Item 3, the variable correlates with a relative displacement angle at which the induced voltage of the electric motor at the rotation speed is maximum and a relative displacement angle at which the operating efficiency of the electric motor is the best. An intermediate value of a variable to be determined is determined as the command value. A control device for an electric motor for controlling a relative displacement angle between a first rotor and a second rotor provided concentrically around a rotation shaft of a permanent magnet field motor,
A rotation speed detector which detects the number of revolutions per unit time of the first rotor or the second rotor,
Based on the requested torque value and the rotational speed detected by the rotational speed detection unit, the relative displacement angle of the first rotor and the second rotor of the electric motor or a variable command correlated with the relative displacement angle A command value determining unit for determining a value;
A control unit that controls a relative displacement angle of the first rotor and the second rotor of the electric motor according to the command value determined by the command value determination unit;
The command value determining unit
On the graph showing the relationship between the torque of the motor and the rotational speed, an area for determining, as the command value, a relative displacement angle at which the induced voltage of the motor at the rotational speed is maximum or a variable related to the relative displacement angle. Depending on the operating state of the motor, the induced voltage of the motor is maximum in an orthogonal region where field weakening control is not required for the motor or in a region where field weakening control is required for the motor. A specific region below a predetermined number of revolutions that is lower than the number of revolutions in which the induced voltage generated when the electric motor is driven in a state of being fixed at a relative displacement angle that exceeds the pressure resistance of the electric motor or the electronic component related to the electric motor, and The motor control device is set in the orthogonal region.

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