JP5124336B2 - Control device for electric vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a controller for electric vehicles wherein a motor having such characteristics that it is stabilized in a weakening phase position is mounted and fluid energy can be reduced. <P>SOLUTION: The controller for electric vehicles includes: a phase changing mechanism that changes a phase between a phase position where synthesized magnetic flux arising from a magnet piece is enhanced and a phase position where it is weakened by supplying working fluid to relatively rotate first and second magnetized rotors; and a motor having such characteristics that it is stabilized on the weakening phase position side. The tile angle of a running road is detected (S14) and a request creep torque Tcrp required at the detected tilt angle is computed (S16). A target value &theta; of phase is determined so that the computed request creep torque Tcrp is satisfied and the fluid pressure of the working fluid is minimized (S18 to S22). The operation of the phase changing mechanism is controlled so that the determined target value is reached (S24). <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a control device for an electric vehicle, and more specifically to a control device for an electric vehicle including an electric motor that changes the phase by relatively rotating two magnetized rotors.

As an example of an electric motor that changes the phase indicating the relative rotation angle by rotating two magnetized rotors relative to each other, a technique described in Patent Document 1 below can be cited. In the technique described in Patent Document 1, the magnet piece is rotated around the same axis, and the magnet piece is arranged so as to face the circumferential direction with the first rotor arranged so that the longitudinal direction thereof faces the radial direction. And a first working chamber defined by a member fixed to one of the rotors and a member fixed to the other, and the first and second working chambers. The working fluid is supplied / discharged through the fluid passage communicated with the working chamber, and the first and second rotors are relatively rotated so that the phase is a phase position where the combined magnetic flux by the magnet piece is strengthened and a phase position where the phase is weakened. It is configured to change between.
JP 2004-072978 A

  By the way, since an electric motor having such a magnet arrangement has a characteristic of being stabilized at a weak phase position, when a large load is expected, the working fluid is supplied to and discharged from the first and second working chambers in advance to increase the phase position. It is necessary to fix to. Therefore, when mounted on a vehicle, a large fluid energy is generated in the working chamber at a high load and a low vehicle speed, and is fixed at a strong phase position, and power consumption in a fluid supply device such as an electric oil pump that supplies fluid is increased. There was an inconvenience of increasing.

  Accordingly, an object of the present invention is to eliminate the above-described problems, and to provide a control device for an electric vehicle that is equipped with an electric motor having a characteristic that is stable at a weak phase position and that can reduce fluid energy. There is.

  In order to achieve the above object, according to claim 1, a plurality of magnet pieces are provided, and first and second rotors that rotate about the same axis and a working fluid are supplied. Then, the first and second rotors are rotated relative to each other about the axis, and the phase indicating the relative rotation angle between the phase position where the combined magnetic flux by the magnet piece is strengthened most and the phase position where it is weakened most. A phase changing mechanism that changes at least between them, and when the working fluid is not supplied, the composite magnetic flux has a characteristic that is stable at a phase position where the combined magnetic flux is strengthened most and an intermediate position between the weakest phase position or the weakest phase position. In a control apparatus for an electric vehicle including an electric motor provided and a wheel driven by the electric motor, an inclination angle detection unit that detects an inclination angle of a travel path on which the electric vehicle travels, and A required creep torque calculating means for calculating a required creep torque required at the tilt angle, and a target of the phase so as to satisfy the calculated required creep torque and minimize the fluid pressure of the working fluid. A phase target value determining means for determining a value and a control means for controlling the operation of the phase changing mechanism so as to be the determined target value are provided.

  In the control apparatus for an electric vehicle according to claim 2, any one of an internal combustion engine and an operation mode in which an occupant can freely operate and places importance on driving force performance and an operation mode that places importance on fuel consumption performance of the internal combustion engine. The phase target value determining means determines the target value so as to minimize the fluid pressure of the working fluid when the operation mode in which the fuel efficiency is emphasized is selected. When the operation mode emphasizing the driving force performance is selected, the target value is determined in the vicinity of the phase position where the combined magnetic flux is most enhanced.

  In the control apparatus for an electric vehicle according to a third aspect, the phase target value determining means is configured to determine the target value when the traveling speed of the vehicle is in a creep state less than a minute vehicle speed.

  In the control apparatus for an electric vehicle according to claim 4, the phase target value determining means is configured to determine the target value when the inter-vehicle distance from the preceding vehicle is in a traffic jam state less than a predetermined value. .

  According to claim 1, the first and second rotors magnetized by supplying the working fluid are rotated relative to each other, and the phase position is the phase position where the combined magnetic flux by the magnet piece is most strengthened and the phase position where it is most weakened. And a characteristic that the combined magnetic flux is stable at the intermediate position between the weakest phase position and the weakest phase position or when the working fluid is not supplied. In the control device for an electric vehicle driven by an electric motor, the inclination angle of the traveling path is detected, the required creep torque required by the detected inclination angle is calculated, and the required creep torque is satisfied and the fluid pressure of the working fluid is reduced. Since the target value of the phase is determined so as to be minimized, and the operation of the phase change mechanism is controlled so as to be the determined target value, it is calculated by detecting the inclination angle of the traveling road. By controlling the phase so as to minimize the fluid pressure that satisfies the required creep torque, it is possible to reduce the fluid energy correspondingly.

  In the control apparatus for an electric vehicle according to claim 2, any one of an internal combustion engine and an operation mode that is provided so as to be freely operated by an occupant and places importance on driving force performance and an operation mode that emphasizes fuel consumption performance of the internal combustion engine. When an operation mode that emphasizes fuel efficiency is selected, a target value is determined so as to minimize the fluid pressure of the working fluid, while an operation mode that emphasizes driving force performance is selected. In this case, since the target value is determined in the vicinity of the phase position where the combined magnetic flux is most strengthened, in addition to the effects described above, the passenger's intention can be well met.

  In the control device for an electric vehicle according to claim 3, since the target value is determined when the traveling speed of the vehicle is in a creep state less than the minute vehicle speed, in addition to the above effect, the vehicle is in an uphill traveling. Sometimes, the necessary driving force can be ensured.

  In the control device for an electric vehicle according to the fourth aspect, the target value is determined when the inter-vehicle distance from the preceding vehicle is in a congested state that is less than a predetermined value. Responsiveness at the time of acceleration can be ensured by performing the above-described control only when traveling in a traffic jam where acceleration cannot be predicted.

  The best mode for carrying out the motor control device according to the present invention will be described below with reference to the accompanying drawings.

  FIG. 1 is a schematic diagram showing the overall configuration of an electric vehicle control apparatus according to an embodiment of the present invention.

  In FIG. 1, symbol V indicates an electric vehicle, specifically a hybrid vehicle, more specifically a series / parallel hybrid vehicle (hereinafter referred to as “vehicle”). The vehicle V includes a spark ignition type internal combustion engine (hereinafter referred to as “ENG”, hereinafter referred to as “engine”) 10 using gasoline as fuel. The output of the engine 10 is connected to the input shaft 14a of the transmission 14 via a damper (flywheel mass) 12 for absorbing torque.

  A first electric motor (motor) 16 is connected to the input shaft 14 a of the transmission 14. The first motor 16 is a brushless or AC synchronous motor. The engine 10 and the first electric motor 16 are directly connected, and when one rotates, the other is also rotated.

  In the transmission 14, the input shaft 14a is connected to a small-diameter first gear 14c via a hydraulic clutch 14b, and the first gear 14c meshes with a large-diameter second gear 14d. The second gear 14d is connected to the small-diameter third gear 14e on the one hand, and similarly meshes with the small-diameter fourth gear 14f on the other hand.

  The third gear 14e is connected to the differential D and is connected to the wheel W through it. A second electric motor (motor) 18 is connected to the fourth gear 14f. The second motor 18 is also a brushless or AC synchronous motor.

  The first and second electric motors 16 and 18 are connected to a battery 22 via a PDU (Power Drive Unit) 20. The PDU 20 includes an inverter, converts direct current (electric power) supplied (discharged) from the battery 22 into alternating current, and supplies the alternating current to the first and second electric motors 16 and 18, and the first and second electric motors 16 and 18. The alternating current generated by the regenerative operation is converted into direct current and supplied to the battery 22.

  When the hydraulic clutch 14b is turned on (engaged), the output of the engine 10 and the first electric motor 16 is transmitted to the first gear 14c, and when turned off (dissociated), the engine 10 and the first electric motor 16 are turned on. Disconnect from the first gear 14c. The second electric motor 18 is always connected to the fourth gear 14f.

  Explaining the travel of the vehicle V, when starting, the hydraulic clutch 14b is turned off and the engine 10 and the first electric motor 16 are disconnected from the transmission 14, while the electric power is supplied from the battery 22 via the PDU 20 and the second electric motor. 18 is activated. The output of the second electric motor 18 drives the wheels W via the fourth gear 14f, and the vehicle V starts.

  When the traveling speed of the vehicle V reaches a certain value, the first electric motor 16 is activated by being supplied with electric power from the PDU 20, and starts by cranking the engine 10. Then, the engine 10 conversely drives the first electric motor 16 and operates the first electric motor 16 as a generator. The second electric motor 18 continues to rotate with the electric power generated by the first electric motor 16 instead of the output of the battery 22. Thus, the first electric motor 16 mainly functions as a generator rather than as an electric motor.

  When the traveling speed of the vehicle V further increases and the vehicle V is in the low load region, the hydraulic clutch 14b is turned on, and the output of the engine 10 is transmitted to the wheels W via the first gear 14c and the second gear 14d. Start driving.

  As the engine 10 is started, the second electric motor 18 is stopped. Even if the second electric motor 18 is stopped, the second electric motor 18 is driven from the side of the wheel W to generate electric power. At this time, the phase of the second electric motor 18 is made weaker so that the second electric motor 18 is not loaded as much as possible.

  In addition, after the vehicle V starts, when the driving force is insufficient with only the second electric motor 18, the hydraulic clutch 14 b is turned on, and the output of the engine 10 (or the first electric motor 16 in addition thereto) is also connected to the wheel W. Is done.

  In FIG. 1, reference numeral 24 denotes an ECU (Electronic Control Unit). The ECU 24 is composed of a microcomputer, and controls the travel of the vehicle V as described above by controlling the operations of the first and second electric motors 16 and 18 via the PDU 20.

  The ECU 24 controls on / off of the clutch 14b via the clutch control hydraulic circuit 260 of the hydraulic mechanism 26, and controls the torques of the first and second electric motors 16 and 18 based on the detection result such as the operating state. At the same time, the phase is controlled via the phase control hydraulic circuit 261.

  The detection of the driving state will be described. A vehicle speed sensor 28 is provided in the vicinity of the drive shaft (not shown) of the vehicle V and outputs a pulse signal every time the drive shaft rotates, and an accelerator pedal (not shown) in the driver's seat. )), An accelerator opening sensor 30 is provided to generate an output indicating the accelerator opening (the amount of depression of the accelerator pedal by the occupant).

  A brake switch 32 is provided in the vicinity of a brake (not shown) of the vehicle V. When a brake is depressed by an occupant, an on signal is output, and a radar device 34 is disposed in front of the vehicle V. An electromagnetic wave is transmitted in the traveling direction of V, a reflected wave reflected by an object such as a preceding vehicle is received, and a relative position (separation distance) and a relative speed with respect to the object such as the preceding vehicle are detected.

  Further, an inclination angle sensor 36 is provided at an appropriate position of the vehicle V, and generates an output indicating an inclination angle (gradient) of a traveling path (road) on which the vehicle V travels. Further, a driving mode selection switch 38 is provided in the vicinity of the driver's seat of the vehicle V, and selects either a driving mode in which driving force performance is emphasized or driving mode in which fuel efficiency performance is emphasized as the traveling of the vehicle V by the operation of the occupant. Configured to be able to.

  The outputs of the sensors and switch groups described above are sent to the ECU 24, and the ECU 24 controls the torque and phase of the first and second electric motors 16 and 18 based on these outputs.

  In FIG. 1, a thick line indicates a high pressure hydraulic system for operation, a thin line indicates a low pressure hydraulic system for lubrication / cooling, and a black circle indicates a bearing. The winding 40a of the stator 40 of the first and second electric motors 16 and 18 is cooled by being supplied with hydraulic oil.

  Next, the structure of the first and second electric motors 16 and 18 will be described with reference to FIG. In the following, the structure of the second electric motor 18 will be described, but the structure is applicable to the first electric motor 16 as it is.

  2 is a cross-sectional view of a main part of the second electric motor 18 shown in FIG. 1, FIG. 3 is an exploded perspective view showing a phase changing mechanism of the electric motor shown in FIG. 2, and FIG. 4 is a diagram of magnetic poles of the rotor magnet shown in FIG. FIG. 5 is a schematic view showing the direction, and FIG. 5 is a side view of the rotor of the electric motor shown in FIG.

  As shown in the figure, the second electric motor 18 includes an annular stator (stator) 40, a similarly annular rotor 42 housed inside the stator 40, and a rotation shaft (rotation axis) 44. The stator 40 is formed by laminating thin plates manufactured from iron-based materials (or casting iron-based materials), and is arranged with three-phase (U, V, W-phase) stator windings 40a.

  The rotor 42 includes an outer peripheral side (first) rotor 42 a and an inner peripheral side (second) rotor 42 b that is relatively displaceable about a rotating shaft (rotating axis) 44. The rotors 42a and 42b are made of, for example, an iron core made of sintered metal, and a plurality of, more specifically 16 sets of elongated magnet pieces (permanent magnets) 46a and 46b are slightly connected to each other on the circumferential side. Are arranged at a certain interval.

  More specifically, as shown in FIG. 5, 16 sets of magnet pieces 46a are arranged on the rotor 42a on the outer peripheral side so that the longitudinal direction of the magnet pieces 46a faces the radial direction of the rotor 42a, Sixteen sets of magnet pieces 46b are arranged on the inner rotor 42b so that the longitudinal direction of the magnet pieces 46b faces the circumferential direction of the rotor 42a, and thus has a U-shape in plan view with the magnet pieces 46a. Is done.

  As shown in FIG. 3, the rotor 42 is provided with a phase changing mechanism 50. The phase changing mechanism 50 includes a vane rotor 52 that is fixed to the rotating shaft 44 via a spline (not shown), an annular housing 54 that is fitted and fixed to the inner peripheral surface of the rotor 42b on the inner peripheral side, The vane rotor 52 includes a pair of drive plates 56 that fix the vane rotor 52 to the rotor 42a on the outer peripheral side with pins 56a, and the hydraulic mechanism 26 that supplies hydraulic oil (working fluid, more specifically, hydraulic pressure) to them.

  The vane rotor 52 is formed with a plurality of (six) vanes (members) 52a projecting from the central boss portion at equal intervals in the radial direction, and the annular housing 54 has an equal interval on the center side. Thus, a plurality of (six) partition walls (members) 54a are formed. Seal members 52b and 54b are disposed at the tips of the vane 52a and the partition wall 54a, respectively, and provide a fluid-tight seal between the vane 52a and the inner wall surface of the annular housing 54 and between the partition wall 54a and the outer peripheral surface of the boss portion of the vane rotor 52. .

  As shown in FIG. 2, the annular housing 54 has an axial length (width) larger than that of the rotor 42b on the inner peripheral side, and an annular groove 56b (FIG. 3) formed in the two drive plates 56. The annular housing 54 and the inner peripheral rotor 42b are rotatably supported by the outer peripheral rotor 42a and the rotating shaft 44.

  The two drive plates 56 are slidably brought into close contact with both side surfaces of the annular housing 54, and a plurality of (6) sealed spaces are formed between the partition wall 54 a of the annular housing 54 and the outer peripheral surface of the boss portion of the vane rotor 52. )Form. This sealed space is divided into two by a vane 52a of the vane rotor 52, and forms an advance side working chamber (first working chamber) 54c and a retard side working chamber (second working chamber) 54d. Here, the “advance angle” (ADV) means that the rotor 42b on the inner circumference side is in the same direction as the rotation direction of the second electric motor 18 indicated by the arrow ADV (FIG. 5) with respect to the rotor 42a on the outer circumference side. The “retard angle” (RTD) means rotating in the opposite direction.

  The advance-side working chamber 54c and the retard-side working chamber 54d have a working fluid, specifically an incompressible fluid, more specifically, an ATF (Automatic Transmission Fluid) of the transmission 14 or a lubricating oil of the engine 10. Of hydraulic oil is supplied. The hydraulic oil is supplied from the rotating shaft 44 to the advance side working chamber 54c and the retard side working chamber 54d through two oil passages 62 and 64 formed in the vane rotor 52.

  The oil passages 62 and 64 are substantially parallel to each other, and as shown in FIGS. 2 and 5, the oil passages 62 a and 64 a drilled in the axial direction of the rotation shaft 44 and the outer peripheral surface of the rotation shaft 44 continuously therewith. The oil passages 62b and 64b are formed, and the oil passages 62c and 64c are formed continuously in the boss portion of the vane rotor 52. The oil passage 62 is connected to the advance side working chamber 54c, and the oil passage 64 is connected to the retard side working chamber 54d, and hydraulic oil is supplied to and discharged from a reservoir described later.

  The advance-side working chamber 54c and the retard-side working chamber 54d expand and contract by being supplied and discharged with hydraulic oil, so that the inner periphery integrated with the partition wall 54a with respect to the vane 52a fixed to the outer rotor 42a. The phase of the relative displacement angle between the outer peripheral rotor 42a and the inner peripheral rotor 42b is reduced from 0 degrees by the relative rotation of the side rotor 42b about the rotation axis (rotation axis) 44. It is changed between 180 degrees, and the induced voltage of the second electric motor 18 is changed accordingly.

  FIG. 5 shows the advance side working chamber 54c and the retard side working chamber 54d at the most advanced position. When in the advanced position, hydraulic fluid is supplied to the advanced working chamber 54c, while hydraulic fluid is discharged from the retarded working chamber 54d, but in the most advanced position, the advanced working chamber 54c is While expanding to the maximum limit, the retard side working chamber 54d contracts to the maximum limit.

  In the second electric motor 18 (and the first electric motor 16) according to this embodiment, as shown in FIG. 4A, the magnet piece 46a of the outer rotor 42a and the inner rotor. When the magnet piece 46b of 42b is in a phase where the same poles are arranged in the same polarity opposite to each other, it becomes a strong field (increase in the field) in which the combined magnetic flux of both is strengthened (in other words, in a strong phase position). ). On the other hand, as shown in FIG. 4B, when the magnet piece 46a of the rotor 42a on the outer peripheral side and the magnet piece 46b of the rotor 42b on the inner peripheral side are in a phase where the different poles are opposed to each other, The resulting magnetic field is weakened (the field is reduced) (in other words, at the weakening phase position).

  The phase of the outer rotor 42a and the inner rotor 42b can be changed between 0 degrees and 180 degrees in electrical angle so that a desired combined magnetic flux can be obtained. The 180 degree side is the advance side. FIG. 4A shows the same-pole arrangement of the magnet pieces 46a and 46b at 0 degree (most retarded angle position). At this time, the field is strengthened most. On the other hand, FIG. 4B shows the counter electrode arrangement of the magnet pieces 46a and 46b at 180 degrees (most advanced angle position), and at this time, the field is weakened most.

  Thereby, the induced voltage constant Ke of the second electric motor 18 is changed, and the characteristics of the second electric motor 18 are changed. That is, when the induced voltage constant Ke increases due to the strong field, the allowable rotational speed at which the second electric motor 18 can operate decreases, but the maximum torque that can be output increases, and conversely the induced voltage constant Ke due to the weak field. When the torque decreases, the maximum torque that can be output decreases and the allowable rotational speed increases.

  In the second electric motor 18 (and the first electric motor 16), the rotor 42b on the inner peripheral side has the most advanced position (phase 180 degrees) or the most retarded position (phase) with respect to the outer rotor 42a. 0 degree) and the most recent angle position (90 degrees), in other words, it is stable when it is on the weaker phase position side. That is, when hydraulic pressure is not supplied, the rotor 42 is relatively displaced by itself toward the most advanced position.

  FIG. 6 is a circuit diagram showing in detail the phase control hydraulic circuit 261 of the hydraulic mechanism 26 that supplies hydraulic oil to the advance side working chamber 54c and the retard side working chamber 54d via the oil passages 62 and 64. is there.

  As shown in the figure, the hydraulic mechanism 26 includes a hydraulic pump 26d that pumps hydraulic oil from a reservoir (tank; hydraulic oil storage source) 26a through a filter 26b, increases the pressure, and outputs the hydraulic pressure as a line pressure to the oil path 26c. The switching valve 26e is connected to the advance-side working chamber 54c and the retard-side working chamber 54d via the oil passages 62 and 64, and the switching valve 26e is inserted into the oil passage 26c. Is provided with a flow rate adjusting valve 26f for adjusting the flow rate of the hydraulic fluid supplied to the advance side working chamber 54c and the retard side working chamber 54d. These operations are controlled by the ECU 24 described above.

  The switching valve 26e is a 4-port valve (direction switching valve). A linear solenoid valve 26g for switching the port is connected to the switching valve 26e. The linear solenoid valve 26g is interposed between the hydraulic pump 26d and the switching valve 26e in the oil passage 26c, and includes an electromagnetic solenoid 26g1. It is possible to switch between a first position where oil, more specifically oil pressure, acts on the spool (not shown) of the switching valve 26e and a second position where the hydraulic oil is drained. A broken line indicates a relief valve system.

  The switching valve 26e has a spool (valve element) that connects the oil passage 26c to the advance side working chamber 54c via the oil passage 62 by the linear solenoid valve 26g and supplies hydraulic oil, while operating on the retard side. The first position where the chamber 54d is connected to the drain side to discharge the hydraulic oil, and the oil passage 26c is connected to the retard side working chamber 54d via the oil passage 64 to supply the hydraulic oil, while the advance side operation is performed. Between the second position where the chamber 54c is connected to the drain side and the hydraulic oil is drained (discharged), and the middle position (neutral) position where the four ports are closed to hold the hydraulic oil between them. It is configured to be switchable. The spool is biased to the second position by the spring 26e1.

  The flow rate adjusting valve 26f is also a linear solenoid valve, and includes an electromagnetic solenoid 26f1. When the electromagnetic solenoid 26f1 is PWM-controlled, hydraulic oil is supplied to the advance side working chamber 54c and the like via the switching valve 26e. Between the first position where the hydraulic oil is drained and the second position where the hydraulic oil is drained is configured to be switchable, and the hydraulic oil having a flow rate corresponding to the switched position is output to the oil passage 26c. Adjust the flow rate of hydraulic oil. A broken line shows a relief valve system.

  The hydraulic oil in the oil passage 26c whose flow rate is adjusted by the flow rate adjusting valve 26f is supplied to the advance side working chamber 54c or the retard side working chamber 54d via the switching valve 26e. As described above, when the hydraulic fluid is supplied, the advance side working chamber 54c expands according to the flow rate thereof, and the phase is set to an arbitrary position between the most advanced position (180 degrees) and the intermediate position (90 degrees). When the hydraulic oil is supplied, the retard side working chamber 54d also expands according to the flow rate, and the phase is between the intermediate position (90 degrees) and the most retarded position (0 degrees). Change to any position.

  As shown at the end of FIG. 6, the hydraulic pump 26d is connected to the second electric motor 26j and driven by the third electric motor 26j. The third electric motor 26j is connected to an inverter circuit (INV) 20a of the PDU 20. Thus, the hydraulic pump 26d is configured as an EOP (Electric Oil Pump).

  The ECU 24 controls the operation of the second electric motor 18 (and the first electric motor 16) via the inverter circuit 20a of the PDU 20, and changes the phase via the phase changing mechanism 50 based on the rotational speed of the second electric motor 18 and the like. Change (control). More specifically, the ECU 24 excites and demagnetizes the linear solenoid 26g and the electromagnetic solenoids 26g1 and 26f1 of the flow rate adjustment valve 26f based on the output of the phase sensor 26n and the like.

  Next, the operation of the control device for the vehicle V according to this embodiment, that is, the ECU 24 will be described.

  FIG. 7 is a flowchart showing the operation.

  In the following, it is determined whether or not the vehicle speed V detected in S10 is less than the creep vehicle speed Vcrp, for example, 5 km / h. In an AT vehicle, when the selector lever is put in the D or R range, a phenomenon called “creep” occurs in which the vehicle moves forward at a minute speed even if the accelerator pedal is not depressed.

  Although the transmission 14 of the vehicle V according to this embodiment is not an automatic transmission, the “creep” vehicle speed in S10 also means the vehicle speed of the creep phenomenon. Therefore, the process of S10 corresponds to determining whether or not the traveling speed VP of the vehicle V is in a creep state that is less than the minute vehicle speed.

  When the result in S10 is negative, the subsequent process is skipped. When the result is affirmative, the process proceeds to S12 to determine whether the inter-vehicle distance R with the preceding vehicle is less than the predetermined value R1, and when the result is negative, the subsequent process is performed. Skip processing. The process of S12 is intended to determine the vehicle V is in a traffic jam state, in other words, a driving state in which it is expected that no sudden acceleration instruction will be given from the occupant.

  When the result in S12 is negative, the subsequent processing is skipped. When the result is affirmative and it is determined that the vehicle V is in a traffic jam state, the process proceeds to S14, and the vehicle V detected by the inclination angle sensor 36 is traveling. Read the inclination angle (gradient) of the road.

  Next, in S16, a table showing the characteristics in FIG. 8 is retrieved from the detected inclination angle (degree), and the required creep torque Tcrp, that is, the required creep torque Tcrp required for the vehicle V at the detected inclination angle is obtained. At the same time, a minimum induced voltage constant command value Ke1 that satisfies the calculated required creep torque Tcrp is calculated. In S16, “inclination angle” means the inclination angle (uphill slope) of the uphill road.

  The above process will be described with reference to FIG.

  FIG. 9A shows the characteristic of the induced voltage constant Ke with respect to the phase (phase angle) of the second electric motor 18. As shown, the induced voltage constant Ke is approximately equal to the torque constant and inversely proportional to the phase. FIG. 9B shows the line pressure and the magnet reaction force torque with respect to the phase when a constant current is supplied to the second electric motor 18.

  In the hydraulic mechanism 26 shown in FIG. 6, the line pressure discharged from the EOP 26 d is large enough to cancel the reaction force torque of the magnet 46, more precisely to a value obtained by adding a slight margin to the reaction force torque of the magnet 46. Is set. However, since the generation G of the vehicle V is large in the vicinity of the strongest phase (0 degree) and the vane 52a may be fluttered, the margin value is increased (in the weakest phase (180 degrees) side, the magnet is increased). The reaction torque acts in the pressing direction and is a stable phase, so that the vane 52a has little fluctuation).

  Therefore, even if the magnet reaction force torque is large, there may be a region where the power consumption of the EOP 26d is smaller than the strongest phase. Therefore, the calculation of the induced voltage constant command value Ke1 in S16 means that Ke1 is narrowed down from the phase interval α in FIG. 9A, in the illustrated example, from 0 degrees to 90 degrees.

  Returning to the description of the flowchart of FIG. 7, the process then proceeds to S18, where the operation mode selected by the occupant via the operation mode selection switch 38 is determined, and it is determined that the operation mode that places importance on driving force performance has been selected. When the process proceeds to S20, the phase (more precisely, the target value of the phase) θ is set to θ1.

  That is, in the region from θ2 to 180 degrees in FIG. 9B, the power consumption of the EOP 26d is smaller than θ1, but the induced voltage constant Ke is small, so the occupant emphasizes the driving force performance. Precisely, the phase target value (θ) is determined as θ1 when the constant Ke is the largest in the range of the induced voltage constant Ke1 calculated in S16. In other words, the target value θ is determined near the phase position where the combined magnetic flux is most strengthened.

On the other hand, when it is determined that the operation mode that emphasizes fuel efficiency is selected, the process proceeds to S22, and the phase θKe1 corresponding to the induced voltage constant Ke1 calculated in S16 is compared with θ2, and the phase (more accurately, the phase Target value) θ is determined. That is, the phase θ is determined as follows.
When 0 <θKe1 <θ2, θ1
When θKe1 ≧ θ2, θKe1

  That is, the target value of the phase that minimizes the power consumption of the EOP 26d is determined from 0 to 180 degrees. More specifically, when the traveling speed of the vehicle V is in a creep state where the traveling speed is less than a minute vehicle speed (creep vehicle speed Vcrp) and the traffic distance R with the preceding traveling vehicle is less than a predetermined value R1, the power consumption of the EOP 26d is Determine the target value of the minimum phase.

  Next, the process proceeds to S24, and a table indicating the characteristics in FIG. 10 is retrieved from the determined phase (phase target value) θ to determine the energization command value to the EOP 26d. Based on the determined energization command value, the operation of the EOP 26d, that is, the operation of the phase changing mechanism 50 is controlled so as to be the determined target value in a routine (not shown).

  Next, the process proceeds to S26, where it is determined whether the accelerator pedal is not operated and the brake pedal is not operated from the outputs of the accelerator opening sensor 30 and the brake switch 32. When the result is affirmative, the process proceeds to S28, and the energization of the second electric motor 18 is controlled so that the output of the second electric motor 18 becomes the required creep torque value Tcrp calculated in S16.

  In this embodiment, as described above, a plurality of magnet pieces 46a and 46b are provided respectively, and the first (outer peripheral side) and second (inner peripheral side) rotors 42a, which rotate about the same axis 44, are provided. 42b and a working fluid (hydraulic oil) are supplied, the first and second rotors are rotated relative to each other about the axis, and the phase indicating the relative rotation angle between the two is enhanced by the combined magnetic flux of the magnet piece. At least a phase changing mechanism 50 that changes between a phase position to be adjusted (0 degree side) and a phase position that is weakest (180 degrees), and a phase position at which the combined magnetic flux is most strengthened when no working fluid is supplied. An electric motor (second electric motor 18) having characteristics stable at an intermediate position (90 degrees) between (0 degree) and the weakest phase position (180 degrees) or at the weakest phase position, and driven by the electric motor In the control device (ECU 24) for the electric vehicle V including the wheels 20, the inclination angle detecting means (inclination angle sensors 36, S14) for detecting the inclination angle of the travel path on which the electric vehicle travels, and the detected inclination The required creep torque calculating means (S10, S12, S16) for calculating the required creep torque Tcrp required by the angle, and satisfying the calculated required creep torque Tcrp and minimizing the fluid pressure of the working fluid. Are provided with phase target value determining means (S18 to S22) for determining the phase target value θ, and control means (S24) for controlling the operation of the phase changing mechanism 50 so as to be the determined target value. Thus, the phase is controlled so that the minimum fluid pressure (hydraulic pressure) that satisfies the required creep torque Tcrp calculated by detecting the inclination angle of the travel path is obtained. As a result, the fluid energy, more specifically, the power consumption of the EOP 26d can be reduced accordingly.

  In addition, an internal combustion engine (engine) 10 and a switch 38 that is provided so as to be freely operated by the occupant and that selects either an operation mode that emphasizes driving force performance or an operation mode that emphasizes fuel efficiency of the internal combustion engine are provided. The phase target value determining means determines the target value so as to minimize the fluid pressure of the working fluid when the operation mode in which the fuel efficiency is emphasized is selected (S22), while the driving force performance is determined. Since the target value is determined in the vicinity of the phase position where the combined magnetic flux is most strengthened (S20) when the operation mode that emphasizes is selected, in addition to the effects described above, It can respond well to the intention that consists of any one that emphasizes fuel efficiency.

  The phase target value determining means determines the target value (S20, S22) when the traveling speed (vehicle speed V) of the vehicle V is in a creep state less than a minute vehicle speed (creep vehicle speed Vcrp) (S10). Since it comprised as mentioned above, in addition to the above-mentioned effect, also when the vehicle V is going uphill driving, a required driving force can be ensured.

  Further, the phase target value determining means is configured to determine the target value (S20, S22) when the vehicle distance R with the preceding vehicle is in a traffic jam state where the inter-vehicle distance R is less than the predetermined value R1 (S12). In addition to the effects described above, the above-mentioned control is performed only when the vehicle is traveling in a traffic jam where sudden acceleration cannot be predicted, so that it is possible to respond promptly even when the passenger intends to accelerate, thus ensuring responsiveness during acceleration. be able to.

  In the above description, the present invention has been described by taking as an example the case where the vehicle V is an electric vehicle, more specifically, a series / parallel hybrid vehicle. However, the present invention includes a normal series hybrid vehicle and further an internal combustion engine. Not applicable to electric cars.

  Moreover, although the inclination angle of the traveling road is detected from the output of the inclination angle sensor 36 in S14 of FIG. 7, the inclination angle may be obtained by acquiring external information such as internavi or by calculation. Further, the distance from the preceding vehicle may be obtained from the visual sensor.

  In addition, the second rotor 42b is relatively rotated about the rotation axis so as to change the phase θ indicating the relative displacement angle between them, but both the first and second rotors are relatively rotated. The phase may be changed.

  Furthermore, although the working oil has been exemplified as the working fluid, other fluids may be used.

1 is a schematic diagram illustrating an overall configuration of a control device for an electric vehicle according to an embodiment of the present invention. It is principal part sectional drawing of the electric motor shown in FIG. It is a disassembled perspective view which shows the phase change mechanism of the electric motor shown in FIG. It is a schematic diagram which shows direction of the magnetic pole of the magnet of the rotor shown in FIG. It is a side view of the rotor of the electric motor shown in FIG. FIG. 6 is a hydraulic circuit diagram of a hydraulic mechanism that supplies hydraulic pressure to the working chamber of the phase change mechanism shown in FIG. 5. 2 is a flowchart showing the operation of the control device for the electric vehicle shown in FIG. 1 and the like. 7 is an explanatory graph showing the characteristics of the required creep torque used in the processing of the flow chart. 7 is an explanatory graph for explaining the processing of the flow chart. 7 is an explanatory graph showing the characteristics of the energization command value to the EOP used in the processing of the flowchart of FIG.

Explanation of symbols

  V vehicle, 10 engine (internal combustion engine), 14 transmission, 16, 18 first and second electric motors (motors), 20 PDU (power drive unit), 22 battery, 24 ECU (electronic control unit), 26 hydraulic mechanism, 26d hydraulic pump (EOP), 26e switching valve (4 port valve), 26g linear solenoid valve, 28 vehicle speed sensor, 30 accelerator opening sensor, 34 radar device, 36 tilt angle sensor, 38 operation mode selection switch, 40 stator, 42 rotor, 42a outer peripheral side (first) rotor, 42b inner peripheral side (second) rotor, 44 rotary shaft (rotation axis), 46a, 46b magnet piece, 50 phase change mechanism, 52 vane rotor, 52a Vane (member), 54 annular housing, 54a partition wall (member), 54c advance side working chamber (first operation) ), 54d retard side hydraulic chamber (second working chamber), 62 and 64 oil passage (fluid passage)

Claims (4)

  A plurality of magnet pieces are provided on each of the first and second rotors rotating around the same axis, and a working fluid is supplied to center the first and second rotors around the axis. At least a phase changing mechanism for changing the phase indicating the relative rotation angle between the phase position where the combined magnetic flux by the magnet piece is most strengthened and the phase position where the combined magnetic flux is most weakened; An electric motor having a characteristic that the composite magnetic flux is stable at a position intermediate between the weakest phase position and the weakest phase position or the weakest phase position, and a wheel driven by the electric motor when not supplied; In a vehicle control device, an inclination angle detecting means for detecting an inclination angle of a traveling path on which the electric vehicle travels, and a required creep torque required for the detected inclination angle are provided. A required creep torque calculating means to be outputted; a phase target value determining means for determining a target value of the phase so as to minimize the fluid pressure of the working fluid while satisfying the calculated required creep torque; And a control means for controlling the operation of the phase change mechanism so as to achieve the set target value.   The phase target value determining means includes an internal combustion engine and a switch that is provided so as to be freely operated by an occupant and that selects either an operation mode that emphasizes driving force performance or an operation mode that emphasizes fuel efficiency of the internal combustion engine. When the operation mode emphasizing the fuel efficiency is selected, the target value is determined so as to minimize the fluid pressure of the working fluid, while the operation mode emphasizing the driving force performance is selected. 2. The control apparatus for an electric vehicle according to claim 1, wherein the target value is determined in the vicinity of a phase position where the combined magnetic flux is strengthened most.   3. The control apparatus for an electric vehicle according to claim 1, wherein the phase target value determining means determines the target value when the traveling speed of the vehicle is in a creep state less than a minute vehicle speed.   The electric vehicle according to any one of claims 1 to 3, wherein the phase target value determining means determines the target value when the inter-vehicle distance from the preceding vehicle is in a traffic jam state less than a predetermined value. Control device.

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