JP2007331682A - Stabilizer system for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a highly-practical active stabilizer system. <P>SOLUTION: The stabilizer system can change a roll suppression force exerted by a stabilizer bar according to an operating amount of an actuator having an electric motor as a driving source. In the stabilizer system, a drive circuit use control or a resistor use control can be selectively performed. In the drive circuit use control, the roll suppression force is controlled by using a drive circuit. In the resistor use control, resistance against motion of the actuator by an external force is given, by using a resistor consuming electric power generated by the electric motor from an electromotive force generated in the electric motor by an external force such as change in roll moment. In this system, the drive circuit use control is performed at normal times, and the resistor use control is performed in the process of reduction in operating amount of the actuator, so as to prevent or suppress problems such as overload on the actuator, abnormal noise and vibration, caused by the drive circuit use control in the process of reduction in operating amount. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a stabilizer system provided in a vehicle, and more particularly to a stabilizer system capable of changing a roll restraining force exerted by a stabilizer bar by operating an actuator.

In recent years, a stabilizer system as described in the following patent document, that is, a so-called active stabilizer system has been studied, and has already been actually installed in some vehicles. This system includes an actuator having an electric motor as a drive source, and the roll suppression force exerted by the stabilizer bar can be changed by the operation of the actuator.
JP 2004-98952 A

  In the stabilizer system described in the above-mentioned patent document, a resistor is connected to the electric motor, and when the electromotive force is generated by an external force such as a disturbance on the road surface or a change in roll moment received by the vehicle body, The device is configured to consume electric power generated by the electric motor by electromotive force. Under such a configuration, the motor force based on the electromotive force is used as a resistance force against the operation of the actuator by the external force using the resistor (hereinafter referred to as “resistor use control”). Is sometimes executed). Resistor use control is control of one suitable stabilizer system, but in an active stabilizer system that is still under development, there is room for improvement in control of the stabilizer system, and the practical use of the stabilizer system by further elaboration It is possible to improve the property. This invention is made | formed in view of such a situation, and makes it a subject to provide a highly practical stabilizer system.

  In order to solve the above problems, a vehicle stabilizer system according to the present invention is a stabilizer system capable of changing a roll restraining force exerted by a stabilizer bar by an operation of an actuator having an electric motor as a drive source. Drive circuit use control for controlling roll suppression force using a drive circuit for supplying electric power to the electric motor and controlling the operation of the electric motor, and for consuming electric power generated by the electric motor by the electromotive force Resistor use control that provides resistance to the operation of the actuator by an external force is selectively executed using the resistor.

  In the above drive circuit use control, it becomes possible to exert a roll restraining force according to the roll moment. In the above resistor use control, even if no power is supplied from the power source, the resistance to the operation of the actuator by an external force is provided. It becomes possible to grant. Since each control can be selectively executed, for example, the control can be switched so that the features of each control can be utilized. According to the present invention, a highly practical stabilizer system can be realized. .

Aspects of the Invention

  In the following, some aspects of the invention that can be claimed in the present application (hereinafter sometimes referred to as “claimable invention”) will be exemplified and described. As with the claims, each aspect is divided into sections, each section is numbered, and is described in a form that cites the numbers of other sections as necessary. This is merely for the purpose of facilitating the understanding of the claimable inventions, and is not intended to limit the combinations of the constituent elements constituting those inventions to those described in the following sections. In other words, the claimable invention should be construed in consideration of the description accompanying each section, the description of the embodiments, etc., and as long as the interpretation is followed, another aspect is added to the form of each section. In addition, an aspect in which constituent elements are deleted from the aspect of each item can be an aspect of the claimable invention.

  In each of the following items, each of the items (1) to (3) corresponds to each of claims 1 to 3, the item (6) is claimed in claim 4, the item (7) is claimed. Each corresponds to item 5.

(1) A stabilizer bar,
An actuator having an electric motor as a power source, and increasing a roll restraining force generated by the stabilizer bar in accordance with an increase in an operation amount;
A drive circuit for supplying power from a power source to the electric motor to control the operation of the electric motor;
In a state connected to the electric motor, a resistor that consumes electric power generated by the electric motor by electromotive force;
(A) a drive circuit use control for controlling a roll restraining force generated by the stabilizer bar by controlling an operation amount of the actuator by controlling the electric motor using the drive circuit; and (B) the resistor A vehicle stabilizer system comprising: a control device that selectively executes resistance use control for providing resistance to an operation due to an external force of the actuator by generating a resistance to the operation of the electric motor using the motor.

  The aspect of this section relates to a stabilizer system capable of changing the roll restraining force exerted by the stabilizer bar by the actuator, and the claimable invention is premised on a so-called active stabilizer. In addition, the “stabilizer bar” in the aspect of this section refers to a roll restraining force that is a force that opposes the roll moment received by the vehicle body, more specifically, an elastic force generated by its own torsion, etc. In the following description, a device constituted by a stabilizer bar and the actuator will be referred to as a “stabilizer device”.

  The configuration of the stabilizer device is not particularly limited. For example, as will be described later, the stabilizer bar is divided into two at the central portion and is constituted by a pair of stabilizer bar members, and an actuator is disposed between the pair of stabilizer bar members. Depending on the force exerted by the motor, the actuator may be configured to relatively rotate the pair of stabilizer bar members to generate the actuator force. In this case, the actuator force is a so-called rotational torque. Also, an actuator is disposed between one end of the stabilizer bar and the wheel holding member so that the actuator generates an actuator force that changes the distance between the one end and the wheel holding member. It may be a simple configuration. Incidentally, the “electric motor” may be a linear motor or a rotary motor.

  In the stabilizer system of the aspect of this section, the control of the actuator, specifically, the control of the electric motor that is the drive source thereof can be executed using a drive circuit such as an inverter. More specifically, for example, the drive circuit is disposed between the electric motor and the power source, and is configured to control the power supplied from the power source to the electric motor. It is controlled by giving a control signal to the circuit. In control using such a drive circuit (hereinafter sometimes referred to as “drive circuit use control”), for example, it becomes possible to exert a roll restraining force in accordance with the roll moment received by the vehicle body. Can be appropriately suppressed. Further, in the stabilizer system according to the aspect of this section, the resistor use control as described above can also be executed. In the resistor usage control, for example, it is possible to give resistance to the operation of the actuator by the external force even when power is not supplied from the power source. Therefore, in the stabilizer system according to the aspect of this section, it is possible to selectively execute two controls each having different characteristics.

  According to the aspect of this section, a highly practical stabilizer system can be realized by selectively executing these two controls so that the respective characteristics of the drive circuit use control and the resistor use control are utilized. Become. The drive circuit use control is a control that exerts a roll restraining force according to the roll moment by driving the electric motor by receiving power from the power source, so it can be considered as a control based on the driving force of the electric motor. it can. That is, in the drive circuit use control, the actuator can be operated against the external force. On the other hand, the resistor usage control is a control that utilizes the force that the electric motor relies on the electromotive force without receiving the power from the power source. Can think. That is, in the resistor usage control, the actuator cannot be operated against the external force, but resistance to the operation of the actuator by the external force can be given. Considering this, for example, when the actuator is to be operated against the external force, that is, when the external force is increasing or when the external force is generated and stable, the drive circuit use control is performed. By executing this, it becomes possible to appropriately suppress the roll of the vehicle body. On the other hand, when there is little need to operate the actuator against the external force, that is, when the external force is decreasing, it is possible to suppress power consumption from the power source by executing resistor use control. .

  The amount of operation of the actuator is often correlated with the force exerted by the actuator, and for a stabilizer system having such a correlation, the aspect of this section shows the amount of operation of the actuator as a direct control target. Instead, the control may be performed such that the force exerted by the actuator is set as a control target and the actuator force becomes the target actuator force. That is, an aspect in which the operation amount of the actuator is an indirect control target is also included in the aspect of this section.

  (2) The vehicle stabilizer system according to (1), wherein the control device executes the resistor use control when the operation amount of the actuator is in a decreasing process.

  The mode of this section is a mode which limited time when performing resistor use control. Considering typical turning of a vehicle, the roll moment received by the vehicle body increases at the beginning of turning, the roll moment stabilizes at the middle of turning, and the rolling moment decreases at the end of turning. For example, when only the drive circuit use control is executed to suppress the roll moment, the roll restraining force required for the drive circuit use control increases in the early stage of the turn and is constant in the middle of the turn. It decreases at the end. Since the “actuator” in this section increases the roll restraining force in response to an increase in the operation amount of the actuator, the operation amount of the actuator is increased at the beginning of the turn and maintained at the middle of the turn. At the end of the turn. When the drive circuit use control is executed in this manner, as will be described in detail later, the direction in which the electric motor actually operates in the initial stage of turning (hereinafter sometimes referred to as the “operation direction of the electric motor”) and the electric motor The direction in which the motor force is exerted (hereinafter sometimes referred to as the “motor force direction”) is the same direction, but at the end of turning, the electric motor operation direction and the motor force direction may not be the same direction. is there. That is, when the operation amount of the actuator is in the process of decreasing, the motor force direction of the electric motor is reversed, which may cause overload, abnormal noise, vibration, etc. to the actuator. Therefore, as in the aspect of this section, when the operation amount of the actuator is in the process of decreasing, the resistor usage control is executed to eliminate or suppress the adverse effects caused by the reversal of the motor force direction of the electric motor. Is possible. In addition, at the end of turning, power is generated by the electromotive force, and power may be generated. At this time, when the drive circuit use control is executed, the generated power is reversely input to the drive circuit and becomes a burden on the drive circuit. In some cases, the generated power is also reversely input to the power supply. It becomes. From this, when the operation amount of the actuator is in a decreasing process, the resistor usage control is executed, so that it is possible to reduce the load on the drive circuit and the power supply due to the power generated by the power generation.

  In this mode, the resistor usage control is executed when the actuator movement amount is in the decreasing process, but the physical quantity that directly or indirectly represents the roll moment received by the vehicle body is in the decreasing process. The same effect as in this section can be expected when the resistor use control is executed. The physical quantity includes various physical quantities such as the lateral moment, the yaw rate, the cornering force, the lateral force, and the slip angle as well as the roll moment itself. Further, the steering angle, the vehicle traveling speed, and the like can also be regarded as physical quantities that indirectly represent the roll moment received by the vehicle body. Furthermore, the same effect as this section can be expected even when the resistor usage control is executed when the target operation amount, which will be described later, is smaller than the actual operation amount of the actuator. it can.

  (3) The vehicle stabilizer system according to (1) or (2), wherein the resistor is capable of changing an electric resistance value.

  The aspect of this section is an aspect in which a limitation relating to the configuration of the resistor is added. According to the aspect of this section, it is possible to change the resistance force against the operation of the actuator due to the external force, and it is possible to control the operation of the actuator. More specifically, as the electrical resistance value is increased, the resistance force is reduced and the actuator becomes easier to move. As the electrical resistance value is reduced, the resistance force is increased and the actuator is less likely to move. Therefore, for example, when the operation amount of the actuator is in a decreasing process, it is possible to appropriately reduce the operation amount of the actuator by using a resistor whose electric resistance value can be changed.

  The “resistor” described in this section may be an electric resistance value that can be changed steplessly or continuously, and an electric resistance value that can be changed stepwise to a limited value of 2 or more. It may be.

  (4) The vehicle according to any one of (1) to (3), wherein the control device has a function of determining a target operation amount that is a target of the operation amount of the actuator according to a roll moment received by a vehicle body. Stabilizer system.

  The aspect of this section is an aspect in which a limitation relating to a method for determining the target operation amount of the actuator is added. When determining the target motion amount “depending on the roll moment” as in this aspect, the target motion amount is determined according to the physical quantity that directly or indirectly represents the roll moment received by the vehicle body as described above. Is possible.

  (5) The vehicle stabilizer system according to (4), wherein the control device executes control so that the operation amount of the actuator becomes the target operation amount as the drive circuit use control.

  The mode described in this section is a mode related to a system that executes drive circuit use control based on the operation amount of the actuator. Specifically, in the aspect of this section, the drive circuit use control is executed so that the operation amount of the actuator is a direct control target, and the operation amount is a target operation amount that provides a desired roll restraining force.

(6) The resistor is capable of changing an electric resistance value,
The control device executes, as the resistor use control, control for changing the electric resistance value of the resistor based on a deviation of the operation amount of the actuator from the target operation amount (paragraph (5) or paragraph (5)). The vehicle stabilizer system described in 1.

  The mode described in this section is a mode related to a system that executes the resistor use control based on a deviation of the operation amount of the actuator from the target operation amount. According to the aspect of this section, the resistance force to the operation of the actuator due to the external force can be changed based on the deviation, and the operation of the actuator can be appropriately controlled. More specifically, for example, the deviation is considered as a guideline for the resistance force against the operation of the actuator due to an external force. As described later, when the deviation is large, the resistance force is reduced, and when the deviation is small, It becomes possible to control the resistance force to be increased.

  (7) The control device executes, as the resistor use control, control to increase the electrical resistance value of the resistor when the deviation of the operation amount of the actuator from the target operation amount is large and to decrease when the deviation is small. The vehicle stabilizer system according to item (6).

  According to the aspect of this section, the actuator becomes easier to operate as the electrical resistance value of the resistor increases, and the actuator becomes difficult to operate as the electrical resistance value of the resistor decreases. It becomes possible to speed up the operation of the actuator, and when the deviation is small, the operation of the actuator is slowed down, that is, the actuator can be operated slowly. Therefore, for example, when the resistor use control described in this section is executed when the operation amount of the actuator is in a decreasing process, the actuator operation amount can be appropriately reduced. The electrical resistance value of the resistor described in this section may be increased continuously as the deviation increases, or may be increased stepwise.

(8) Each of the stabilizer bars includes a torsion bar portion disposed on one axis extending in the vehicle width direction, and extends continuously across the torsion bar portion and intersects with the torsion bar portion, and a distal end portion. And a pair of stabilizer bar members each having an arm portion connected to one of the wheel holding members that hold each of the left and right wheels.
The vehicle stabilizer system according to any one of (1) to (7), wherein the actuator relatively rotates a torsion bar portion of the pair of stabilizer bar members around the axis.

  The mode described in this section is a mode in which a specific structure of the stabilizer device, more specifically, a limitation on the configuration of the stabilizer bar and the actuator is added. According to the aspect of this section, the roll restraining force exhibited by the stabilizer bar can be changed efficiently.

  (9) The actuator includes a speed reducer that decelerates rotation of the electric motor, and a housing that supports the electric motor and the speed reducer, and one torsion bar portion of the pair of stabilizer bar members includes The vehicle stabilizer system according to (8), wherein the housing is connected to the housing in a relatively non-rotatable manner, and the other torsion bar portion is connected to the output unit of the speed reducer in a relatively non-rotatable manner.

  The mode described in this section is a mode in which the structure of the actuator and the connection and arrangement relationship between the actuator and the stabilizer bar are specifically limited. In the aspect of this section, the mechanism of the speed reducer included in the actuator is not particularly limited. For example, it is possible to employ speed reducers of various mechanisms such as a harmonic gear mechanism (sometimes referred to as a “harmonic drive (registered trademark) mechanism”, a “strain wave gearing mechanism”, etc.), a planetary gear mechanism, or the like. Considering the miniaturization of the electric motor, it is desirable that the reduction ratio of the reduction gear is relatively large (meaning that the operation amount of the actuator is small relative to the operation amount of the electric motor), and considering that point, the harmonic gear mechanism The speed reducer that employs is suitable in the system of the aspect of this section. Further, when a reduction gear having a large reduction ratio is employed, it is expected that the resistance force to the operation of the actuator due to the external force will increase. Therefore, it is particularly beneficial to perform resistor usage control for an actuator that employs a reduction gear having a large reduction ratio.

  Hereinafter, embodiments of the claimable invention will be described in detail with reference to the drawings. In addition to the following examples, the claimable invention includes various aspects in which various modifications and improvements have been made based on the knowledge of those skilled in the art, including the aspects described in the above [Aspect of the Invention] section. Can be implemented.

≪Stabilizer system configuration≫
FIG. 1 schematically shows a vehicle stabilizer system 10 which is an embodiment of the claimable invention. The stabilizer system 10 includes two stabilizer devices 14 disposed on the front wheel side and the rear wheel side of the vehicle. Each of the stabilizer devices 14 includes a stabilizer bar 20 connected to each of suspension lower arms as wheel holding members that hold the left and right wheels 16 at both ends via a link rod 18 as a connecting member ( (See FIG. 2). The stabilizer bar 20 includes a pair of stabilizer bar members into which the stabilizer bar 20 is divided, that is, a right stabilizer bar member 22 and a left stabilizer bar member 24. The pair of stabilizer bar members 22 and 24 are connected to each other via an actuator 30 so that they can rotate relative to each other. Roughly speaking, the stabilizer device 14 has the actuator 30 relative to the left and right stabilizer bar members 22 and 24. By rotating, the apparent rigidity of the entire stabilizer bar 20 is changed to suppress the roll of the vehicle body. Although illustration is omitted, a suspension spring is disposed between the suspension lower arm and a part of the vehicle body so that the wheel and the vehicle body are elastically supported.

  The stabilizer device 14 disposed on the front wheel side illustrated in FIG. 2A and the stabilizer device 14 disposed on the rear wheel side illustrated in FIG. explain. Each of the stabilizer bar members 22 and 24 of the stabilizer device 14 includes a torsion bar portion 32 that extends generally in the vehicle width direction, and an arm portion that is integrated with the torsion bar portion 32 and that intersects with the torsion bar portion 32 and extends generally forward or backward. 36. The torsion bar portions 32 of the stabilizer bar members 22 and 24 are rotatably supported by a support portion 40 fixedly provided on the vehicle body at positions close to the arm portion 36 and are arranged coaxially with each other. As will be described in detail later, the end of each torsion bar 32 (the end opposite to the arm 36) is connected to the actuator 30. On the other hand, the end portion of each arm portion 36 (the end portion opposite to the torsion bar portion 32 side) is connected to the wheel holding member via the link rod 18.

  As schematically shown in FIG. 3, the actuator 30 includes an electric motor 70 and a speed reducer 72 that decelerates the rotation of the electric motor 70. The electric motor 70 and the speed reducer 72 are provided in a housing 74 that is an outer shell member of the actuator 30. As can be seen from the figure, the left stabilizer bar member 24 is fixedly connected to the end of the housing 74, and the right stabilizer bar member 22 is disposed so as to extend into the housing 74, and The housing 74 is supported so as to be rotatable and not movable in the axial direction. An end portion of the right stabilizer bar member 22 existing in the housing 74 is connected to the speed reducer 72.

  The electric motor 70 includes a plurality of coils 84 that are fixedly arranged on one circumference along the inner surface of the peripheral wall of the housing 74, a hollow motor shaft 86 that is rotatably held in the housing 74, and a motor shaft. The permanent magnet 88 includes a permanent magnet 88 that is fixedly arranged on one circumference so as to face the coil 84 on the outer circumference of the 86. The electric motor 70 is a motor in which the coil 84 functions as a stator and the permanent magnet 88 functions as a rotor, and is a three-phase DC brushless motor.

  The speed reducer 72 includes a wave generator 90, a flexible gear (flex spline) 92, and a ring gear (circular spline) 94, and includes a harmonic gear mechanism. The wave generator 90 is configured to include an elliptical cam and a ball bearing fitted on the outer periphery thereof, and is fixed to one end of the motor shaft 86. The flexible gear 92 has a cup shape in which the peripheral wall portion can be elastically deformed, and a plurality of teeth (400 teeth in this embodiment) are formed on the outer periphery on the opening side of the peripheral wall portion. The flexible gear 92 is connected to and supported by the right stabilizer bar member 22 described above. More specifically, the right stabilizer bar member 22 penetrates the motor shaft 86, and the end portion extending from the motor shaft 86 penetrates the bottom portion of the flexible gear 92 as the output portion of the speed reducer 72, and is serrated with the bottom portion. They are connected so that they cannot be rotated relative to each other and cannot move relative to each other in the axial direction. The ring gear 94 is generally ring-shaped and has a plurality of teeth (402 teeth in this embodiment) formed on the inner periphery thereof, and is fixed to the housing 74. The flexible gear 92 has a peripheral wall that is externally fitted to the wave generator 90 and is elastically deformed into an elliptical shape. The flexible gear 92 meshes with the ring gear 94 at two positions located in the major axis direction of the ellipse and does not mesh at other positions. It is said that. When the wave generator 90 makes one revolution (360 degrees), that is, when the motor shaft 86 of the electric motor 70 makes one revolution, the flexible gear 92 and the ring gear 94 are relatively rotated by two teeth. That is, the reduction ratio of the reduction gear 72 is set to 1/200.

  With the above configuration, a force that relatively changes the distance between one of the left and right wheels 16 and the vehicle body and the distance between the other of the left and right wheels 16 and the vehicle body, that is, a roll moment, acts on the vehicle body by turning the vehicle or the like. In this case, a force that relatively rotates the left and right stabilizer bar members 22 and 24, that is, an external force acts on the actuator 30. In that case, the actuator 30 causes the external force to be generated by a motor force that is generated by the electric motor 70 (the electric motor 70 is a rotary motor and can be considered as a rotary torque, and may be referred to as a rotary torque). When the force that opposes the actuator force is exerted as an actuator force, one stabilizer bar 20 constituted by the two stabilizer bar members 22 and 24 is twisted. The elastic force generated by this twist becomes a force that opposes the roll moment, that is, a roll restraining force. And if the relative rotational position of the left and right stabilizer bar members 22 and 24 is changed by changing the rotational position (which is the operating position) of the actuator 30 by the motor force, the roll suppression force changes, It becomes possible to change the roll amount of the vehicle body. The stabilizer device 14 is thus a device that can change the apparent rigidity of the stabilizer bar 20.

  The actuator 30 is provided with a motor rotation angle sensor 100 in the housing 74 for detecting the rotation angle of the motor shaft 86, that is, the rotation angle of the electric motor 70. The motor rotation angle sensor 100 mainly includes an encoder in the actuator 30, and the relative rotation angle (relative rotation position) of the left and right stabilizer bar members 22, 24, in other words, the operation amount of the actuator 30, that is, the rotation amount. As an index, it is used for control of the actuator 30, that is, control of the stabilizer device 14.

  In this stabilizer system 10, as shown in FIG. 1, two stabilizer electronic control units (stabilizer ECUs) 102 corresponding to each stabilizer device 14 are provided. Each of the stabilizer ECUs 102 is a control device that controls the operation of each stabilizer device 14, more specifically, each actuator 30. Although not shown, an inverter 103 serving as a drive circuit and a computer including a CPU, ROM, RAM, and the like are provided. And a controller 104 as a main body. The electric motor 70 included in each stabilizer device 14 is selectively connected to the variable resistor 108 whose electric resistance value is variable via the changeover switch 106 and each inverter 103 connected to the battery 112 via the converter 110. Has been to be. The converter 110 has a structure capable of boosting the voltage supplied from the battery 112, and electric power is supplied from the battery 112 to each electric motor 70 via the corresponding inverter 103. Incidentally, a power source is configured including the converter 110 and the battery 102. Since the electric motor 70 is driven at a constant voltage, the amount of supplied power is changed by changing the amount of supplied current, and the electric motor 70 exhibits a force corresponding to the amount of supplied current.

  Each controller 104 includes the motor rotation angle sensor 100, a steering sensor 120 for detecting an operation angle of the steering wheel as an operation amount of the steering operation member as a steering amount, and a lateral acceleration actually generated in the vehicle body. A lateral acceleration sensor 122 that detects actual lateral acceleration is connected. Each controller 104 is further connected to a brake electronic control unit 124 (hereinafter sometimes referred to as “brake ECU”) which is a control device of the brake system. The brake ECU 124 is connected to a wheel speed sensor 126 that is provided for each of the four wheels and detects the rotational speed of each of the four wheels. It has a function to estimate the traveling speed. Each controller 104 is connected to the brake ECU 124, and acquires the vehicle speed therefrom as necessary. Furthermore, each controller 104 is also connected to the corresponding inverter 103 and variable resistor 108, and controls them respectively by controlling them. Incidentally, the controllers 104 can communicate with each other. Note that a ROM provided in the computer of each controller 104 stores a program described later, various data related to the control of each stabilizer device 14, and the like.

≪Inverter and variable resistor configuration≫
As shown in FIG. 4, the electric motor 70 is a Δ-connected three-phase DC brushless motor, and can be selectively connected to either the inverter 103 or the variable resistor 108 via the changeover switch 106. ing. The inverter 103 includes two switching elements on the high side (high potential side) and low side (low potential side) for each phase (U, V, W) (hereinafter, each of the six switching elements). (Referred to as “UHC”, “ULC”, “VHC”, “VLC”, “WHC”, “WLC”). The phase switching circuit determines the rotation phase (electrical angle) based on the detection signal of the motor rotation angle sensor 100, and outputs a control signal according to the rotation phase. According to the control signal, ON / OFF switching of each of the six switching elements is executed.

  In the stabilizer system 10, the switching elements UHC, ULC, VHC, VLC, WHC, and WLC are turned on / off according to the rotation phase of the electric motor 70 by a so-called 120 ° energizing rectangular wave drive. . There are two switching patterns, and the direction in which the motor force is generated differs depending on the pattern. Further, by switching each switching element, ON / OFF control according to a ratio (duty ratio) between a pulse on time and a pulse off time by PWM (Pulse Width Modulation), that is, duty control is performed. By changing the duty ratio, the amount of current supplied to the electric motor 70 is changed. A command from the controller 104 is input to the phase switching circuit, and a switching pattern and a duty ratio are determined based on the command.

  The variable resistor 108 includes three variable resistors 134 disposed between the energization terminals of each phase of the electric motor 70 and a resistance value changing circuit 136 that changes the electric resistance value of the variable resistors 134. Has been. A command from the controller 104 is input to the resistance value changing circuit 136, and the electrical resistance value is changed based on the command.

≪Control of stabilizer device≫
i) Drive circuit use control In this stabilizer system 10, normally, drive circuit use control is performed so that the rotation position of the actuator 30 becomes the target rotation position using the inverter 130 as the drive circuit in order to suppress the roll of the vehicle body. Is done. More specifically, in the drive circuit use control, the target rotation position of the actuator 30 is determined according to the roll moment received by the vehicle body in order to exert the roll suppression force according to the roll moment generated in the vehicle body, and the rotation of the actuator 30 is determined. The position is controlled to be the target rotational position. Here, the rotational position of the actuator 30 means the amount of movement of the actuator 30, and the rotational position of the actuator 30 in the reference state is defined as a neutral position where no roll moment acts on the vehicle body. In some cases, this means the amount of rotation from that neutral position. Further, since the rotation amount of the actuator 30 and the motor rotation angle, which is the rotation angle of the electric motor 70, are in a corresponding relationship, in actual control, they are acquired by the motor rotation angle sensor 100 instead of the rotation amount of the actuator 30. Motor rotation angle is used.

The target rotation amount of the actuator 30, that is, the target motor rotation angle θ *, is determined based on the lateral acceleration indicating the roll moment received by the vehicle body in order to exert an appropriate roll suppression force according to the roll moment. More specifically, based on the estimated lateral acceleration Gyc estimated based on the steering wheel operating angle and the vehicle speed, and the actually measured actual lateral acceleration Gyr, the control lateral acceleration Gy * which is the lateral acceleration used for control. Is determined according to the following equation:
_{Gy * = K 1 · Gyc +} K 2 · Gyr
Here, K ₁ and K ₂ are gains, and the target motor rotation angle θ * is determined based on the control lateral acceleration Gy * determined as described above. The controller stores map data of the target motor angle θ ^{* using} the control lateral acceleration Gy ^* as a parameter, and the target motor angle θ ^* is determined with reference to the map data. Then, by feeding back the actual motor rotation angle θ, which is the actual motor rotation angle, the target supply current i ^* to the electric motor 70 is determined according to the feedback control method based on the motor rotation angle. More specifically, first, a motor rotation angle deviation Δθ (= θ ^* −θ), which is a deviation of the actual motor rotation angle θ from the determined target motor rotation angle θ ^*, is recognized. Then, the target supply current i ^* for the electric motor 70 is determined according to the following equation using the motor rotation angle deviation Δθ as a parameter.
i ^* = Ka · Δθ + Kb · Int (Δθ)
This equation follows the PI control law. The first term and the second term mean the proportional term and the integral term, respectively, and Ka and Kb mean the proportional gain and the integral gain, respectively. Int (Δθ) corresponds to an integral value of the motor rotation angle deviation Δθ, and is approximated to the target motor rotation angle θ ^* (may be considered approximate to the actual motor rotation angle θ). Can be)
i ^* = Ka · Δθ + Kb · θ ^*
Can be considered equivalent. Therefore, in the drive circuit use control in the present system 10, when determining the target supply current i ^* , it is determined according to the above equation, not the equation according to the PI control law.

The formula for determining the target supply current i ^* is composed of two terms, and each of the two terms can be considered as a component of the target supply power. The component of the first term is a component based on the motor rotation angle deviation Δθ (hereinafter sometimes referred to as “deviation-dependent current component”) i _h , and the component of the second term is a component based on the target motor rotation angle θ ^*. (hereinafter referred to as "target rotation angle relying current component") as i _m in the following equation.
i _h = Ka · Δθ
i _m = Kb · θ ^*
The motor rotation angle deviation Δθ represents the direction in which the actual motor rotation angle θ should approach the target motor rotation angle θ ^* , that is, the operation direction of the electric motor 70 and the amount to be operated by the sign thereof. That is, the deviation-dependent current component i _h can be considered as a current component necessary for rotating the electric motor 70 against an external input. In contrast, the target rotation angle relying current component i _m, in order to exert a steady motor force necessary for maintaining the operational position of the actuator 30, the power components to be supplied to the electric motor 70, in other words It can be considered as operating position holding power. That is, it can be considered as a current component for preventing the electric motor 70 from being rotated by an external input. In view of the above, in the present stabilizer system 10, the target supply current i ^* is determined as the sum of the two current components.

The target supply current i ^* can be considered to represent the motor force direction of the electric motor 70 because the power supply direction differs depending on the sign of the target supply current i ^* . Therefore, based on the target supply current i ^* , the duty ratio to the electric motor 70 and the direction of the motor force are determined, and the electric motor 70 is operated according to them. More specifically, a command regarding the motor force direction and the duty ratio based on the determined target supply current i ^* is issued to the inverter 130, and as described above, the switching element of the inverter 130 is switched, and the electric motor 70 is switched. Is activated.

In the present embodiment, the target supply current i ^* is determined according to the PI control law, but the target supply current i ^* can also be determined according to the PDI control law. In this case, for example, the following formula: i ^* = Ka · Δθ + Kb · Int (Δθ) + Kc · Δθ ′
Thus, the target supply current i ^* may be determined. Here, Kc is a differential gain, and the third term means a differential term component. Further, in the target supply current i ^* according to the PDI control law, the sum of the proportional term of the first term and the differential term of the third term corresponds to the deviation-dependent current component i _h, and the integral term of the second term is it can be thought of as corresponding to the target rotation angle relying current component i _m.

ii) Relationship between the direction of operation of the electric motor and the direction of the motor force in the drive circuit use control FIG. 5 shows an example of a typical one-turn operation, and the roll suppression force Is and the target motor rotation required in the drive circuit use control. Angle θ ^* , The relationship among the actual motor rotation angle θ, the deviation-dependent current component i _h , the target rotation angle-dependent current component i _m , and the target supply current i ^* is schematically shown in a graph with the passage of time as the horizontal axis. In one turning operation of the vehicle, the roll suppression force Is changes as follows according to the roll moment received by the vehicle body. First, at the initial turning [a], the roll restraining force Is increases as the steering angle increases. Subsequently, in the turning middle period [b], steady turning with a constant steering angle is performed, and the roll restraining force Is is constant. At the end of turning [c], the roll restraining force Is decreases as the steering angle decreases. Correspondingly, the target motor rotation angle θ ^* and the actual motor rotation angle θ, that is, the operation amount of the actuator 30 are in an increasing process at the initial turning [a], and decreased at the final turning [c]. In the process. However, the actual motor rotation angle θ varies as shown in the figure because it involves a certain delay with respect to the target motor rotation angle θ ^* . That is, in the initial turning stage [a] where the roll restraining force Is changes, the operation direction of the electric motor 70 is a direction away from the neutral position, and in the latter turning period [c], the operation direction of the electric motor 70 approaches the neutral position. It becomes.

Target supply current i ^* is to the electric motor 70, as previously described, the sum of the deviation-dependent current component i _h and the target rotation angle relying current component i _m, according to changes in each of them changes to become. The two components i _h, will be described a i _m respectively, the deviation-dependent current component i _h is determined based on the motor rotational angle deviation [Delta] [theta], the initial stage of cornering [a], to distance the actual motor rotation angle θ from the neutral position , A value for exerting the motor force in the same direction as the operation direction of the electric motor 70, generally 0 in the turning middle period [b], and in the final turning stage [c], the actual motor rotation angle θ is brought closer to the neutral position. This is a value for exerting the motor force in the same direction as the operation direction of the electric motor 34. In contrast, the target rotation angle relying current component i _m, since those serve as operation position holding power, throughout the turning of the vehicle, the actual motor rotation angle θ in the direction of movement of the electric motor 70 from the neutral position The value depends on the target motor rotation angle θ ^* in order to maintain the position at a distance. In other words, the direction of the motor force exerted on the basis of the target rotation angle relying current component i _m is the initial stage of cornering [a], but the same direction as the operation direction of the electric motor 70, the swivel late [c], generally The direction of operation of the electric motor 70 is opposite.

In the turning end [c], due to friction or the like of the speed reducer 36, when the actual motor rotational angle θ changes as wavy, this change, the deviation-dependent current component i _h and the target rotation angle relying current component i _m The direction of the motor force exerted on the basis of the target supply current i ^* , which is the sum of the above, is likely to be the opposite direction or the same direction as the operation direction of the electric motor 70. Such reversal of the motor force direction of the electric motor 70 contributes to overload, abnormal noise, vibration and the like on the actuator 30. In consideration of this, in the present stabilizer system 10, when the operation amount of the actuator 30 is in a decreasing process, in other words, when the operation amount of the actuator 30 is in a decreasing process, the above drive circuit use control is not performed. Control as described below is executed.

iii) Resistor use control When the operation amount of the actuator 30 is in a decreasing process, the roll moment is also decreased as described above, and therefore it is not necessary to operate the actuator against an external force such as a change in the roll moment. . That is, it is possible to appropriately reduce the operation amount of the actuator 30 by appropriately applying resistance to the operation of the actuator 30 due to external force. That is, when the operation amount of the actuator 30 is decreasing, the electric motor and a resistor for consuming electric power generated by the electric motor by the electromotive force are connected, and the motor force based on the electromotive force is Using the resistor, control is performed so as to act as a resistance force against the operation of the actuator by the external force (hereinafter also referred to as “resistor use control”). By doing so, it becomes possible for the electric motor 70 to appropriately reduce the operation amount of the actuator 30 without causing the motor force direction to be reversed. Further, in the system 10, when the resistor use control is executed, the resistance force against the operation of the actuator 30 due to an external force is changed by changing the electric resistance value of the resistor. By doing in this way, it becomes possible to reduce the operation amount of the actuator 30 more appropriately. Since the reduction ratio of the reduction gear 72 employed in the suspension system 10 is a high reduction ratio as described above, the motor force that relies on the electromotive force is relative to the operation of the actuator 30 due to an external force. It can be a relatively large resistance.

  In the resistor use control in the stabilizer system 10, the resistance value against the operation of the actuator 30 due to an external force is changed by changing the electric resistance value of the variable resistor 134 included in the variable resistor 108. More specifically, for example, when the electric resistance value of the variable resistor 134 is increased, the motor force based on the electromotive force is reduced, so that the resistance force against the operation of the actuator 30 due to the external force is also reduced, while the electric resistance value is reduced. Then, since the motor force depending on the electromotive force increases, the resistance force against the operation of the actuator 30 due to the external force also increases. Therefore, in order to appropriately reduce the operation amount of the actuator 30, when the actuator 30 is to be operated quickly by an external force, in other words, when the motor rotation angle deviation Δθ is large, the electric resistance value is increased, When it is desired to make the actuator 30 move easily, on the other hand, when the actuator 30 is to be operated slowly, in other words, when the motor rotation angle deviation Δθ is small, the electrical resistance value is reduced to make the actuator 30 difficult to move.

  More specifically, when the resistor use control is executed, the connection between the electric motor 70 and the inverter 103 is disconnected by the changeover switch 106 based on the changeover signal from the controller 104, and the electric motor 70. Are connected to the variable resistor 108. Then, the controller 104 determines the electric resistance value R of the variable resistor 108 based on the motor rotation angle deviation Δθ. More specifically, the controller 104 stores map data of an electric resistance value R using the motor rotation angle deviation Δθ as a parameter as shown in FIG. 6 and referring to the map data, the electric resistance value R is stored. Is determined. A control signal corresponding to the electric resistance value R is input from the controller 104 to the resistance value changing circuit 136, and the resistance value changing circuit 136 determines the electric resistance value of each of the variable resistors 134 of the three variable resistors 108. Change the value according to the signal. Thereby, the electric motor 70 can control the resistance force to the operation of the actuator 30. By executing this resistor use control, the reversal phenomenon in the motor force direction of the electric motor 70 is suppressed, and the occurrence of overload, abnormal noise, vibration, etc. to the actuator 30 is prevented or suppressed. Further, in the resistor usage control, the power of the battery 112 is not consumed, so that the power saving of the system 10 can be achieved. Furthermore, since the connection between the electric motor 70 and the inverter 103 is disconnected as described above, it is possible to prevent the power generated by the electric motor 70 from the electromotive force from flowing backward toward the inverter 103. . That is, it is possible to prevent a voltage increase at the output unit of the inverter 103, the converter 110, and the like, and to reduce the burden on the inverter 103, the converter 110, and the like.

≪Stabilizer control program≫
The control of the stabilizer device 14 is executed repeatedly by the controller 104 with a short time interval (for example, several msec) while the ignition switch is in the ON state, while the stabilizer control program shown in the flowchart of FIG. Is done by. Hereinafter, the control flow of the stabilizer device 14 will be briefly described with reference to the flowchart shown in the drawing. The stabilizer system 10 includes two stabilizer ECUs 102, that is, two controllers 104, corresponding to the two stabilizer devices 14. In each controller 104, the stabilizer device corresponding to each of them. The following control processing for 14 is executed independently.

  In the processing by this program, first, in step 1 (hereinafter simply referred to as “S1”; the same applies to other steps), the vehicle speed v is acquired based on the calculated value of the brake ECU 124, and the steering wheel operating angle is obtained. δ is acquired based on the detection value of the steering sensor 120. Next, in S2, the estimated lateral acceleration Gyc is estimated based on the vehicle speed v and the operation angle δ acquired in S1. The controller 104 of the stabilizer ECU 102 stores map data related to the estimated lateral acceleration Gyc using the vehicle speed v and the operation angle δ as parameters, and the estimated lateral acceleration Gyc is estimated by referring to the map data. Subsequently, in S <b> 3, the actual lateral acceleration Gyr that is the lateral acceleration actually generated in the vehicle body is acquired based on the detection value of the lateral acceleration sensor 122. In the subsequent S4, the control lateral acceleration Gy * is determined from the estimated lateral acceleration Gyc and the actual lateral acceleration Gyr as described above. In S5, the target motor rotation angle θ * is determined based on the control lateral acceleration Gy *. The Next, in S6, the actual motor rotation angle θ is acquired based on the motor rotation angle sensor 100, and in S7, a motor rotation angle deviation Δθ that is a deviation of the actual motor rotation angle θ from the target motor rotation angle θ * is determined. .

  Subsequently, it is determined whether or not the operation amount of the actuator 30 is decreasing. Specifically, in S8, it is determined whether or not the target motor rotation angle θ * is positive. If it is positive, in S9, is the target motor rotation angle θ * smaller than the actual motor rotation angle θ? It is determined whether or not. If it is determined that the operation amount of the actuator 30 is small, it is determined that the operation amount of the actuator 30 is in a decreasing process, and if it is determined otherwise, it is determined that the operation amount of the actuator 30 is not in a decrease process. If it is determined in S8 that the target motor rotation angle θ * is not positive, it is determined in S10 whether the target motor rotation angle θ * is larger than the actual motor rotation angle θ. When it is determined that it is large, it is determined that the operation amount of the actuator 30 is in a decreasing process, and when it is determined that it is not large, it is determined that the operation amount of the actuator 30 is not in a decreasing process.

  When it is determined that the operation amount of the actuator 30 is in a decreasing process, the switch 106 is operated so as to connect the electric motor 70 and the variable resistor 108 in S11 in order to execute the resistor use control. In S12, the electric resistance value R of the variable resistor 108 is determined based on the motor rotation angle deviation Δθ. In S13, a control signal corresponding to the determined electrical resistance value R is output from the controller 104 to the variable resistor 108. On the other hand, if it is determined that the operation amount of the actuator 30 is not in the decreasing process, the changeover switch 106 is operated so as to connect the electric motor 70 and the inverter 103 in S14 in order to execute the drive circuit use control. In step S15, the target supply current i * is determined as described above. In step S <b> 16, a control signal corresponding to the determined target supply current i * is output from the controller 104 to the inverter 103.

≪Functional structure of controller≫
The controller 104 of the present suspension system 10 that functions by executing the control program as described above can be considered to have a functional configuration as shown in FIG. 8 according to the execution process. As can be seen from the functional configuration diagram, the controller 104 is a target operation amount determination unit as a function unit that executes the process of S5, that is, a function unit that determines the target motor rotation angle θ * that is the target operation amount of the actuator 30. 150 is a functional unit that executes the processing from S8 to S10, that is, a functional unit that authorizes that the operation amount of the actuator 30 is in the decreasing process, and the operation amount decreasing process recognition unit 152 is executed, and the processing from S11 to S13 is executed A resistor usage control unit 154 is provided as a functional unit that performs the resistor usage control. Further, the controller 138 includes a drive circuit use control unit 156 as a function unit that executes the processes of S14 to S16, that is, a function unit that executes drive circuit use control. The resistor usage control unit 154 is a functional unit that executes the process of S12, that is, a functional unit that determines the electrical resistance value R of the variable resistor 108. Reference numeral 156 includes a target supply current determination unit 160 as a function unit that executes the process of S15, that is, a function unit that determines the target supply current i *.

It is a perspective view which shows the whole structure of the stabilizer system which is an Example of claimable invention. It is the schematic which shows the stabilizer apparatus with which the stabilizer system of FIG. 1 is provided. It is a schematic sectional drawing which shows the actuator which comprises a stabilizer apparatus. It is a circuit diagram which shows the inverter and variable resistor with which the stabilizer system of FIG. 1 is provided. Roll restraint force, target motor rotation angle during a typical turning operation of the vehicle, 6 is a chart schematically showing changes of an actual motor rotation angle, a proportional term current component, an integral term current component, and a target supply current with time. It is a figure which shows notionally the map data for determining the electrical resistance value of a variable resistor by using a motor rotation angle deviation as a parameter. It is a flowchart which shows the stabilizer control program performed in the stabilizer system of FIG. It is a block diagram which shows the function of the stabilizer electronic control apparatus which manages control of the stabilizer system of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10: Stabilizer system for vehicles 20: Stabilizer bar 22: Right stabilizer bar member 24: Left stabilizer bar member 30: Actuator 32: Torsion bar part 36: Arm part 70: Electric motor 72: Reduction gear 74: Housing 102: Stabilizer electronic control Unit (stabilizer ECU) (control device) 103: Inverter (drive circuit) 108: Variable resistor (resistor) 110: Converter (power source) 112: Battery (power source)

Claims (5)

A stabilizer bar,
An actuator having an electric motor as a power source, and increasing a roll restraining force generated by the stabilizer bar in accordance with an increase in an operation amount;
A drive circuit for supplying power from a power source to the electric motor to control the operation of the electric motor;
In a state connected to the electric motor, a resistor that consumes electric power generated by the electric motor by electromotive force;
(A) a drive circuit use control for controlling a roll restraining force generated by the stabilizer bar by controlling an operation amount of the actuator by controlling the electric motor using the drive circuit; and (B) the resistor A vehicle stabilizer system comprising: a control device that selectively executes resistance use control for providing resistance to an operation due to an external force of the actuator by generating a resistance to the operation of the electric motor using the motor.   The vehicle stabilizer system according to claim 1, wherein the control device executes the resistor use control when an operation amount of the actuator is in a decreasing process.   The vehicle stabilizer system according to claim 1, wherein the resistor is capable of changing an electric resistance value. The resistor is capable of changing an electric resistance value,
The control device has a function of determining a target operation amount that is a target of the operation amount of the actuator according to a roll moment received by a vehicle body, and the resistance based on a deviation of the operation amount of the actuator from the target operation amount The vehicle stabilizer system in any one of Claim 1 thru | or 3 which performs control which changes the electrical resistance value of a resistor as said resistor use control. The control device executes, as the resistor use control, control for increasing the electrical resistance value of the resistor when the deviation of the operation amount of the actuator from the target operation amount is large and decreasing it when the deviation is small. 5. The vehicle stabilizer system according to 4.

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