JP2019119337A - Electric brake device - Google Patents

Abstract

To provide an electric brake device capable of determining an abnormality in angle estimation inexpensively and at the time of a brake operation or the like.SOLUTION: A control device 2 of an electric brake device has an angle estimation function unit 26 for estimating a motor angle, a reaction force estimation function unit 27 for estimating a reaction force of a pressing force of a friction material 9, and an angle estimation abnormality detection function unit 24 for determining the presence or absence of an abnormality of the angle estimation function unit 26. The angle estimation abnormality detection function unit 24 has a data acquisition unit 29 for acquiring an estimated angle and an estimated reaction force as data, a reaction force correlation deriving unit 28 for estimating a reaction force correlation that associates the estimated angle with the estimated reaction force acquired by the data acquisition unit 29 according to a predetermined condition, and an abnormality determination unit 31 for determining that the angle estimating function unit 26 is abnormal when a degree of coincidence between the reaction force correlation estimated by the reaction force correlation deriving unit 28 and the data acquired by the data acquisition unit 29 is below a predetermined reference.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an electric brake system, and relates to a technology capable of determining abnormality in angle estimation inexpensively and at the time of brake operation or the like.

The following techniques have been proposed as an electric motor device and an electric actuator using the electric motor.
(1) A technology for reducing the rotational driving force of an electric motor by a reduction gear and converting it into a linear motion via a linear motion mechanism, pressing the friction pad against the disc rotor to apply a braking force (Patent Document 1) .
(2) A technology for operating the motor when the brake is not operated and judging abnormality of the brake (Patent Document 2).

JP 2003-247576 Japanese Patent Application Laid-Open No. 11-170991

  For example, in an electric brake device using an electric actuator as in Patent Document 1, for example, when used for an application such as a brake of a vehicle, in general, extremely high safety is often required. In particular, if an abnormality occurs in the sensor system of the electric brake device, there is a high possibility that a serious operation abnormality will occur. Therefore, it is important to accurately detect the abnormality of the sensor system.

Above all, in the above-mentioned electric brake device, it is often difficult to detect an abnormality in the angle sensor. As a countermeasure, for example, in the case of providing a plurality of angle sensors for redundancy, the cost and mounting space of the sensors may be a problem.
For example, when driving an electric motor in a situation where the driver does not operate the brake and judging an abnormality as in Patent Document 2, when an abnormality occurs at the time of the brake operation, the abnormality can not be detected and the operation abnormality occurs. There is.

  An object of the present invention is to provide an electric brake system capable of judging abnormality of angle estimation inexpensively and at the time of brake operation and the like.

The electric brake device 1 according to the present invention includes a brake rotor 8, a friction member 9 which generates a braking force by coming into contact with the brake rotor 8, an electric motor 4, and an output of the electric motor 4 In an electric brake device provided with friction material operating means 6 for converting into pressure and a control device 2 for controlling the electric motor 4
The control device 2 is
An angle estimation function unit 26 for estimating the angle of the electric motor 4;
A reaction force estimation function unit 27 for estimating a reaction force due to a reaction of the pressing force of the friction material 9;
And an angle estimation abnormality detection function unit 24 that determines presence or absence of an abnormality of the angle estimation function unit 26;
The angle estimation abnormality detection function unit 24
A data acquisition unit that acquires, as data, an estimated angle that is an angle estimated by the angle estimation function unit 26 or a parameter equivalent to the estimated angle, and an estimated reaction force that is a reaction force estimated by the reaction force estimation function unit 27 29, and
A reaction force correlation deriving unit 28 for estimating a reaction force correlation that associates the estimated angle or the parameter acquired by the data acquiring unit 29 with the estimated reaction force according to a defined condition;
When the degree of coincidence between the reaction force correlation estimated by the reaction force correlation deriving unit 28 and the data acquired by the data acquiring unit 29 falls below a predetermined reference, the angle estimating function unit 26 is abnormal. And an abnormality determination unit 31 that determines that
The above-defined conditions and the above-mentioned criteria are the conditions and criteria arbitrarily determined by the design etc., for example, determined by finding the appropriate conditions and criteria by either or both of the test and the simulation. .
Good agreement between the estimated reaction force correlation and the data means that the degree of coincidence is high, and meaning that the degree of coincidence is low when the estimated reaction force correlation is not largely coincident with the data. Do.

According to this configuration, the reaction force correlation deriving unit 28 estimates a reaction force correlation that associates the acquired estimated angle or parameter with the estimated reaction force according to a defined condition. The abnormality judgment unit 31 evaluates the degree of coincidence between the estimated reaction force correlation and the original data (that is, the actual result). The abnormality determining unit 31 determines that the angle estimation function unit 26 is abnormal when the degree of coincidence falls below a predetermined reference.
In the angle estimation function unit 26, for example, when an abnormality such as sticking of the output occurs, the estimated angle stops in that state. At this time, since the angle does not move, the magnitude of the estimated reaction force increases, for example, to the maximum torque that can be exhibited by the electric motor 4. At this time, the reaction force correlation between the estimated angle and the estimated reaction force draws a locus like a broken point with high discontinuity from a continuous curve depending on the actuator stiffness. Because of this, the degree of agreement of the original data with such trajectories results in relatively large estimation errors. Therefore, when the degree of coincidence falls below the defined reference, the angle estimation function unit 26 can be judged to be abnormal. As described above, the abnormality in the angle estimation can be determined more inexpensively than in the prior art and also at the time of the brake operation or the like.

The reaction force correlation deriving unit 28 has a reference correlation function that associates the estimated angle or the parameter with the estimated reaction force as the determined condition, and the reference correlation function and the data acquisition unit 29 acquire the reference correlation function. Has a function of deriving the reaction force correlation that minimizes an evaluation index based on an error with the extracted data,
When the evaluation unit based on the error at the time of estimation of the reaction force correlation is evaluated in the abnormality determination unit 31 when the evaluation corresponding to a state in which the error is larger than the determined amount is performed, the abnormality estimation unit 31 You may judge that it is abnormal.
The predetermined amount is an amount arbitrarily determined by design or the like, and is determined by determining an appropriate amount by, for example, one or both of a test and a simulation.
According to this configuration, since the degree of coincidence can be calculated relatively easily, it is possible to accurately detect an angle estimation abnormality of the electric brake device 1 and to enhance redundancy. In addition, since the abnormality of the angle estimation function unit 26 can be determined without providing a plurality of angle sensors or the like, the cost of the sensor can be reduced.

The reaction force correlation is a reaction force correlation that relates the estimated angle and the estimated reaction force in a first brake cycle which exerts a braking force from a state in which the brake is released to when the brake is released again,
The abnormality determination unit 31 performs the first estimated angle and the first estimated reaction force during a second brake cycle that is performed after the first brake cycle and causes the brake force to be exerted from the released state of the brake. When the amount of deviation with respect to the reaction force correlation determined during the braking cycle is larger than a predetermined amount, it may be determined that the angle estimation function unit 26 is abnormal.
The predetermined amount is an amount arbitrarily determined by design or the like, and is determined by determining an appropriate amount by, for example, one or both of a test and a simulation.
According to this configuration, even when it is difficult to perform the correlation estimation in real time due to the operation load etc., it is possible to estimate the abnormality of the angle estimation function unit 26 using the correlation when the brake is operated. It becomes.

The control device 2 has an angular velocity estimation function unit 25 for estimating the angular velocity of the electric motor 4, and the electric motor 4 is the friction material based on an estimated angular velocity which is an angular velocity estimated by the angular velocity estimation function unit 25. Determine whether the pressure of 9 is rotating in the direction of pressure increase or in the direction of pressure decrease,
The reaction force correlation deriving unit 28 is, as the reaction force correlation, a positive operation correlation when the electric motor 4 is rotating in the pressure rising direction, and a case where the electric motor 4 is rotating in the pressure lowering direction. Has a function to estimate the inverse operation correlation,
The abnormality determination unit 31 determines the degree of coincidence of the positive operation correlation when the electric motor 4 is rotating in the pressure rising direction, and the reverse operation correlation when the electric motor 4 is rotating in the pressure decreasing direction. When one or both of the coincidence degree and the coincidence degree fall below a predetermined reference, it may be judged that the angle estimation function unit 26 is abnormal.
The predetermined standard is a standard which is arbitrarily determined by design or the like, and is determined, for example, by searching for an appropriate standard by one or both of a test and a simulation.
According to this configuration, the electric brake device 1 provided with the friction material operating means 6 and the like exhibits hysteresis characteristics under the influence of the frictional force and the like, so that the positive operation time and the step-down direction when the electric motor 4 rotates in the pressure rising direction. The accuracy of the abnormality determination can be improved by evaluating the abnormality of the angle estimation function unit 26 separately from the reverse operation at the time of rotation.

The control device 2 has an angular velocity estimation function unit 25 for estimating the angular velocity of the electric motor 4, and the electric motor 4 is the friction material based on an estimated angular velocity which is an angular velocity estimated by the angular velocity estimation function unit 25. 9 has a function to determine whether it is rotating in the direction of pressure increase or in the direction of pressure decrease,
The reaction force correlation deriving unit 28 has one of a positive operation correlation when the electric motor 4 is rotating in the pressure rising direction and a reverse operation correlation when the electric motor 4 is rotating in the pressure decreasing direction. It has a function of estimating one, and has a function of estimating the other's correlation via a defined conversion factor based on the correlation of any one of the estimated positive-acting correlation or reverse-acting correlation,
The abnormality determination unit 31 determines the degree of coincidence of the positive operation correlation when the electric motor 4 is rotating in the pressure rising direction, and the reverse operation correlation when the electric motor 4 is rotating in the pressure decreasing direction. The angle estimation function unit 26 may be determined to be abnormal when either one or both of the coincidence degrees falls below a predetermined reference.
The defined conversion factor and the defined standard are conversion factors and standards arbitrarily determined by design etc., and an appropriate conversion factor and standard are determined by, for example, either or both of test and simulation. Is determined.
According to this configuration, in the actuator characteristics, when the efficiency characteristics at the time of normal operation and at the time of reverse operation are strongly related to each other, the operation correlation of either the positive or the reverse can also be defined, and the calculation The load can be reduced.

The control device 2 has a function of regarding the electric motor 4 as being in a stop state when the estimated angular velocity is smaller than a predetermined magnitude,
When the electric motor 4 can be considered to be in a stopped state, the control device 2 can use the positive parameter from one of the first parameters to derive the reaction force correlation based on the positive operation correlation and the reverse operation correlation. Has a function of deriving another second parameter based on the operation correlation and the inverse operation correlation,
The abnormality determining unit 31 determines that the second parameter is out of the range expanded from the range of the second parameter group derived based on the normal operation correlation and the reverse operation correlation based on the error correction ratio. At this time, it may be determined that the angle estimation function unit 26 is abnormal.
The predetermined size and the error correction ratio are respectively an arbitrary size determined by design etc. and an error correction ratio, for example, an appropriate size according to any one or both of test and simulation, error correction Determined by determining the ratio.
According to this configuration, it is possible to determine the abnormality of the angle estimation function unit 26 not only at the time of the positive / reverse operation of the electric motor 4 but also at the time of the hysteresis.

The reaction force correlation deriving unit 28 includes, as the determined condition, a reaction force and an angle including a variable stiffness parameter α that changes the stiffness based on the stiffness of the components of the electric brake device 1 including the friction material 9. A second combination function f2 based on the first combination function f1 of the first combination function f1, the second combination function f2 based on the rigidity of the components of the electric brake device 1 other than the components included in the first combination function f1, and the first combination function Using the deformation ratio β between the component related to f 1 and the component related to the second combined function f 2, for the estimated reaction force p and the estimated angle or estimated position x,
The variable stiffness parameter α and the deformation ratio β may be determined so as to minimize the variance of the calculation error due to p = f1 (α, βx) + f2 ((1−β) x).
According to this configuration, the calculation load can be reduced by defining the shape of the correlation function in advance to some extent and reducing the related variables.

The control device 2 has a load estimation function unit 19 that estimates the pressing force of the friction material 9;
The reaction force correlation is a reaction force correlation that associates an estimated load, which is a pressing force estimated by the load estimation function unit 19, with the estimated reaction force,
The abnormality determination unit 31 determines that the angle estimation function unit 26 is abnormal when the degree of coincidence between the reaction force correlation and the data acquired by the data acquisition unit 29 falls below a predetermined reference. You may
The predetermined standard is a standard which is arbitrarily determined by design or the like, and is determined, for example, by searching for an appropriate standard by one or both of a test and a simulation.
According to this configuration, since the reaction force correlation between the estimated reaction force and the estimated load is not affected by the nonlinear stiffness of the actuator, the correlation can be set relatively easily.

The control device 2 has an angular acceleration estimation function unit 33 for estimating the angular acceleration of the electric motor 4 or a value corresponding to this angular acceleration,
The reaction force correlation deriving unit 28 estimates the reaction force correlation using the estimated reaction force and the estimated angle under the condition that the estimated angular acceleration estimated by the angular acceleration estimation function unit 33 is smaller than the determined magnitude. Good.
The predetermined size is an arbitrary size determined by design or the like, and is determined by obtaining an appropriate size by, for example, one or both of a test and a simulation.
Under conditions where the angular velocity is large, the accuracy of the reaction force estimation may decrease due to an inertia moment error or the like. Therefore, according to this configuration, it is possible to improve the accuracy of the abnormality determination by estimating the reaction force correlation by excluding such a state in which the angular velocity is large.

  The electric brake device according to the present invention comprises a brake rotor, a friction material which contacts the brake rotor to generate a braking force, an electric motor, and a friction material operation which converts the output of the electric motor into a pressing force of the friction material. And a control device for controlling the electric motor, wherein the control device includes an angle estimation function unit for estimating an angle of the electric motor, and a counteraction by a reaction force of the pressing force of the friction material. The reaction force estimation function unit for estimating the force, and the angle estimation abnormality detection function unit for judging presence / absence of abnormality of the angle estimation function unit, and the angle estimation abnormality detection function unit is the angle estimation function unit. A data acquisition unit for acquiring, as data, an estimated angle which is an estimated angle or a parameter equivalent to the estimated angle, and an estimated reaction force which is a reaction force estimated by the reaction force estimation function unit; A reaction force correlation deriving unit that estimates a reaction force correlation that associates the estimated angle or the parameter acquired by the data acquisition unit with the estimated reaction force according to a defined condition, and the reaction force estimated by the reaction force correlation deriving unit And an abnormality determination unit that determines that the angle estimation function unit is abnormal when the degree of coincidence between the correlation and the data acquired by the data acquisition unit falls below a defined reference. For this reason, it is possible to judge the abnormality of the angle estimation inexpensively and at the time of the brake operation or the like.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows roughly the electrically-driven brake device which concerns on embodiment of this invention. It is a block diagram of the control system of the same electric brake device. It is a flowchart which shows the example of execution of the angle estimation abnormality detection function part of the same electric brake device. It is a figure which shows the operation example of the same electric brake device. FIG. 6 is a view showing a normal operation example of the electric brake device without sticking of the angle sensor in the example of FIG. 4. It is a block diagram of a control system of an electric brake device concerning other embodiments of this invention. It is a flowchart which shows the example of execution of the angle estimation abnormality detection function part of the electric brake device which concerns on other embodiment of this invention. It is a figure which shows the operation example of the same electric brake device. It is a flowchart which shows the example of execution of the angle estimation abnormality detection function part of the electric brake device which concerns on other embodiment of this invention. It is a flowchart which shows the example of execution of the angle estimation abnormality detection function part of the electric brake device which concerns on other embodiment of this invention. FIG. 14 is a block diagram of a control system of an electric brake device according to still another embodiment of the present invention. It is a figure which shows the operation example of the same electric brake device.

An electric brake device according to an embodiment of the present invention will be described with reference to FIGS. 1 to 5. The electric brake device is mounted on, for example, a vehicle.
As shown in FIG. 1, the electric brake device 1 includes an electric linear motion actuator DA, a power supply 3, and a friction brake BR. First, the structures of the electric linear actuator DA and the friction brake BR will be described.

<Structure of electric linear actuator DA and friction brake BR>
As shown in FIG. 1, the electric linear actuator DA includes an actuator body AH and a control device 2 described later. As shown in FIGS. 1 and 2, the actuator main body AH includes an electric motor 4, a reduction mechanism 5, a direct acting mechanism 6 as friction material operating means, a parking brake mechanism 7, an angle sensor Sa, and a load sensor. And Sb.

  As shown in FIG. 1, when the electric motor 4 is constituted by a permanent magnet type synchronous motor, it is possible to save space and achieve high efficiency and high torque, which is preferable. However, for example, a DC motor using a brush or a permanent magnet is not used. A reluctance motor, an induction motor or the like can also be applied.

  The reduction mechanism 5 is a mechanism that reduces the rotation of the electric motor 4 and includes a primary gear 12, an intermediate gear 13, and a tertiary gear 11. In this example, the reduction mechanism 5 reduces the rotation of the primary gear 12 attached to the rotor shaft 4 a of the electric motor 4 by the intermediate gear 13 and transmits it to the tertiary gear 11 fixed to the end of the rotating shaft 10 It is possible.

  The linear motion mechanism 6 is a mechanism that converts the rotational motion output from the speed reduction mechanism 5 into linear motion of the linear motion portion 14 by the feed screw mechanism, and causes the friction material 9 to contact and separate from the brake rotor 8. The linear motion portion 14 is detentated and supported movably in the axial direction indicated by the arrow mark A1. A friction material 9 is provided at the outboard side end of the linear movement portion 14. By transmitting the rotation of the electric motor 4 to the linear motion mechanism 6 through the reduction mechanism 5, the rotational motion is converted into a linear motion, which is converted into the pressing force of the friction material 9 to generate a braking force. . In the state where the electric brake device 1 is mounted on a vehicle, the outside in the vehicle width direction of the vehicle is referred to as the outboard side. The center side of the vehicle in the vehicle width direction is called the inboard side.

  As an actuator 16 of the parking brake mechanism 7, for example, a linear solenoid is applied. The locking member 15 is advanced by the actuator 16 and fitted into a locking hole (not shown) formed in the intermediate gear 13 for locking, and the rotation of the intermediate gear 13 is prohibited, whereby the parking lock state is obtained. Make it By disengaging the lock member 15 from the locking hole, the rotation of the intermediate gear 13 is allowed to be in the unlocked state.

  As shown in FIG. 2, the angle sensor Sa detects the angle of rotation of the electric motor 4. As the angle sensor Sa, for example, using a resolver or a magnetic encoder is preferable because of high accuracy and high reliability, but various sensors such as an optical encoder can also be applied. Instead of using the angle sensor Sa, for example, it is possible to use angle sensorless estimation in which the motor angle is estimated from the relationship between the voltage and the current of the electric motor 4 or the like in the control device 2 described later.

  The load sensor Sb detects displacement or deformation of a predetermined portion on which the load of the linear motion mechanism 6 acts. As such a load sensor Sb, for example, a magnetic sensor, a strain sensor, a pressure sensor or the like can be used. Instead of using the load sensor Sb, the control device 2 may perform load sensorless estimation from the motor angle, the electric brake device stiffness, the motor current, the efficiency of the electric actuator DA, and the like. Alternatively, for example, other external sensors may be used, such as a sensor that detects a wheel torque of a wheel on which the friction brake BR is mounted or a longitudinal force of a vehicle on which the electric brake device 1 is mounted. Also, various sensors such as a thermistor may be separately provided according to the requirements.

  As shown in FIG. 1, the friction brake BR has a brake rotor 8 that rotates in conjunction with the wheels of the vehicle, and a friction member 9 that contacts the brake rotor 8 to generate a braking force. The friction material 9 is disposed near the brake rotor. A mechanism may be used in which the friction material 9 is operated by the actuator body AH and pressed against the brake rotor 8 to generate a braking force by the frictional force. The brake rotor 8 and the friction member 9 may be, for example, a disk brake device using a brake disk and a caliper, or may be a drum brake device using a drum and a lining.

<About control device 2>
As shown in FIG. 2, each control device 2 controls the corresponding electric motor 4. The power supply device 3 and a host ECU 17 which is an upper control means of each control device 2 are connected to each control device 2. The power supply device 3 supplies power to the electric motor 4 and the control device 2. The power supply device 3 can apply, for example, a low voltage (for example, 12 V) battery of a vehicle on which the electric brake device 1 is mounted.

  For example, an electric control unit (Vehicle Control Unit, VCU) that controls the entire vehicle is applied as the host ECU 17. The host ECU 17 has an integrated control function of each control device 2. The host ECU 17 includes command means 17a. The command means 17a sets a target brake force command value for each control device 2 according to the output of a sensor that changes in accordance with the amount of operation of the brake operation means (not shown). Output. The command means 17a may be the brake operation means itself or may not depend on the operation of the brake operation means, for example, judging the braking in the autonomous driving vehicle and outputting the command value to each control device 2 respectively. Is also possible.

  Each control device 2 includes various control calculation function units that perform control calculations, a current sensor Sc, and a motor driver 18. The various control operation function units are configured by, for example, a processor such as a microcomputer or an arithmetic unit such as an FPGA or an ASIC and a peripheral circuit. The various control calculation function units include a load estimation function unit 19, a current estimation function unit 20, a load control function unit 21, a current control function unit 22, a motion state estimation function unit 23, and an angle estimation abnormality detection function unit 24.

  The load estimation function unit 19 has a function of estimating the load (estimated load) used for the control calculation from the output of the load sensor Sb. Alternatively, as described above, the load estimation function unit 19 may perform load sensorless estimation for obtaining an estimated load without using the load sensor Sb.

As the current sensor Sc, for example, a sensor formed of an amplifier that detects a voltage across the shunt resistor, or a noncontact sensor that detects a magnetic flux or the like around the current path can be used.
The current estimation function unit 20 has a function of estimating the current used for control calculation from the output of the current sensor Sc. Alternatively, as another configuration of FIG. 2, for example, a terminal voltage of an element or the like constituting the motor driver 18 may be detected, or a motor phase current may be estimated from a current on the primary side. Alternatively, without providing any current sensor, feedforward control can be performed based on characteristics such as resistance or inductance of the electric motor 4 in the current control function unit 22 described later.

  The load control function unit 21 calculates an operation amount so that the estimated load follows the command value requested by the command unit 17a. The operation amount may be, for example, a motor torque, and may be a current norm or a current vector. The control calculation of the load control function unit 21 may use, for example, the load command value and the estimated load directly for the control calculation, or may convert the braking force into another physical quantity such as an angle to perform the control calculation. In addition to load feedback control, for example, a plurality of minor feedback loops may be provided such that a motor current control loop is provided in a braking force control loop. It may be a structure to calculate. Alternatively, feed forward control or the like may be used, or feedback control and feed forward control may be used in combination as appropriate.

  The current control function unit 22 has a function of driving the electric motor 4 with a motor torque or current, which is an operation amount of the load control function unit 21, as a command value. In particular, in the case where the command value is a motor torque, the current control function unit 22 may have a current conversion function of obtaining a current command value for exerting a predetermined motor torque, which is estimated by the angular velocity estimation function unit 25. It is preferable that the electric motor 4 can be driven to a high output if it has a function of deriving a current command value in accordance with a predetermined condition such as a motor angular velocity. Also, for current control of the current control function unit 22, for example, current feedback control may be used, or feedforward control may be used based on predetermined motor characteristics, and these current feedback control and feedforward control may be used in combination as appropriate. May be

  The motion state estimation function unit 23 includes an angle estimation function unit 26 that estimates a motor angle, the angular velocity estimation function unit 25, and a reaction force estimation function unit 27 that estimates a reaction force due to a reaction by the pressing force of the friction material 9. Have. The angle estimation function unit 26 has a function of estimating the angle (estimated angle) of the electric motor 4 used for the control calculation from the output of the angle sensor Sa. Note that the angle estimation function unit 26 may perform angle sensorless estimation for obtaining an estimated angle without using the angle sensor Sa.

  The motion state estimation function unit 23 can configure a state estimation observer that includes physical properties such as actuator inertia in a state transition formula using, for example, an operation amount such as a motor torque and an estimated angle. The angular velocity estimation function unit 25 and the reaction force estimation function unit 27 can be provided by including a reaction force or the like. Alternatively, the motion state estimation function unit 23 estimates a parameter equivalent to the state quantity, for example, by the reaction force estimation function unit 27 using a disturbance observer, and the angular velocity estimation function unit 25 that estimates angular velocity by differential calculation of estimated angles. You may In addition to the configuration of FIG. 2, for example, an angular velocity sensor may be provided, and an angle (estimated angle) may be derived as a state quantity that is an integral equivalent of the angular velocity detected by this angular velocity sensor.

  The angle estimation abnormality detection function unit 24 determines the presence or absence of an abnormality of the angle estimation function unit 26. The angle estimation abnormality detection function unit 24 is a reaction force correlation deriving unit 28 that estimates a correlation between an estimated reaction force and an estimated angle, and a reaction force correlation as a data acquisition unit that acquires data for deriving a reaction force correlation. Based on the convergence results of the data storage unit 29 for estimation, the convergence operation unit 30 for converging the result of the reaction force correlation derivation unit 28 to an appropriate result, and judging the abnormality of the angle estimation function unit 26 from the convergence results of the reaction force correlation derivation unit 28 And an abnormality judging unit 31.

  The reaction force correlation deriving unit 28 estimates a predetermined reaction force correlation (predetermined function) that associates the estimated reaction force with the estimated angle. The predetermined function may be, for example, a method of setting the adjustment coefficient in a function including a predetermined polynomial and an adjustment coefficient for adjusting a gradient or non-linearity, or a polynomial coefficient having a higher degree of freedom Can be set directly.

  For example, in the friction brake BR, it can be said that the caliper stiffness, the actuator stiffness, and the brake rotor stiffness are generally constant from the design stage except for minute effects due to temperature. On the other hand, friction material rigidity changes largely due to wear. That is, the coefficient of stiffness change due to wear of the friction material 9, the function f1 (α, x1) with the amount of deformation of the wear material x1 as a variable, and the function f2 (x2) with the amount of deformation x2 of the caliper, actuator etc. as a variable The reaction force p can be set to p = f1 (α, x1) + f2 (x2).

  Furthermore, with respect to the deformation amount x1 of the wear material and the deformation amount x2 of the caliper or the like, finally by setting the rigidity ratio β to x1 = β · x and x2 = (1−β) x with respect to the total deformation amount x Assuming that the reaction force p is p = f1 (α, βx) + f2 ((1-β) x) and the convergence operation for the binary values of the variables α and β should be performed, the convergence solution is compared using the response surface method etc. Can be easily obtained. The deformation amounts x, x 1 and x 2 may be motor angle conversion values, or may be linear displacement amounts through equivalent leads and the like.

  Further, the estimated reaction force exhibits hysteresis characteristics with respect to the direction of pressure increase / decrease of the actuator body AH. Therefore, the reaction force correlation derivation unit 28 estimates the positive operation correlation estimation unit 28a that estimates the positive operation correlation during positive operation when the electric motor 4 is rotating in the pressure increasing (boosting) direction, and the electric motor 4 And a reverse operation correlation estimation unit 28b for estimating a reverse operation correlation during reverse operation rotating in the direction of step-down), and it is preferable to distinguish the forward operation correlation estimation unit 28a and the reverse operation correlation estimation unit 28b for each situation is there. At this time, although the normal operation and the reverse operation can be distinguished from, for example, the polarity of the motor angular velocity, etc., data near the angular velocity zero at which the normal operation and the reverse operation are switched is excluded in the correlation estimation. It is preferable because the estimation accuracy can be improved.

  With regard to the estimated angle, it may have a function of complementing the periodic motion of the overlap or underlap angle in a predetermined cycle to derive a continuous angle. For example, when the load in the electric brake device is generally shifted from zero to the maximum value with respect to one cycle in the angle sensor Sa or angle sensorless estimation such as a resolver, the electric motor rotates by an amount corresponding to a plurality of cycles. By performing the complement, the total rotation angle can be derived.

  The reaction force correlation estimation data storage unit 29 has a function of accumulating data to be used in the reaction force correlation derivation unit 28. At this time, the reaction force correlation estimation data storage unit 29 may use, for example, a process that does not store data as long as at least one of the estimated reaction force and the estimated angle does not change by a predetermined amount or more. By using the above-described process, it is preferable to be able to suppress an increase in operation load due to sampling of data that is not meaningful in deriving correlation. Alternatively, for example, processing such as sampling at the time of rapid acceleration of a motor which easily causes an error in the estimated reaction force may be provided.

  The convergence operation unit 30 can have a function of performing a convergence operation for obtaining a predetermined function that relates the estimated reaction force and the estimated angle based on, for example, a least squares method represented by the Levenberg-Muckart method or the like. As an end condition of the convergence operation in the convergence operation unit 30, when the error is less than a predetermined value, when an extreme value of the error reduction tendency is detected, a predetermined repetition number can be used, etc. You may

  For example, the abnormality determination unit 31 may evaluate the error reduction value of the convergence calculation result, and may determine that the angle estimation function unit 26 is abnormal if the error is large. In other words, the abnormality determination unit 31 determines the degree of agreement between the reaction force correlation estimated by the reaction force correlation derivation unit 28 and the data acquired by the reaction force correlation estimation data storage unit 29 When the height of) falls below a defined reference, the angle estimation function unit 26 can be judged to be abnormal.

  The motor driver 18 controls the power supplied to the coil of the electric motor 4. The motor driver 18 constitutes, for example, a half bridge circuit using a switch element such as a field effect transistor (abbreviated as FET), and performs PWM control to determine a motor applied voltage by an ON-OFF duty ratio of the switch element. It is cheap and high performance when it is configured to Alternatively, a transformer circuit or the like may be provided to perform PAM control.

  Among the half bridge circuits, as a switching potential source of the H arm switch element for connection to the positive side of the power supply device 3, charges are accumulated from a predetermined potential source when the L arm switch element is turned on, It is preferable to provide a charge circuit using a bootstrap capacitor that functions as a potential source to be applied to the gate when the H arm switch element is turned on, since the motor driver 18 can be driven at low cost.

This figure only shows the concept of the functional configuration, and elements not shown are appropriately provided according to the requirements. Also, each functional block is provided for the sake of convenience, and can be appropriately integrated or divided according to the convenience of mounting.
Moreover, the connection form of each function is shown as an example, and can be changed in the range which does not disturb the above-mentioned function. For example, the parameters estimated in the motion state estimation function unit can also be used in the load control function unit not connected in this figure.

<Execution flow example of angle estimation error detection function unit>
FIG. 3 is a flow chart showing an example of execution of the angle estimation abnormality detection function unit of the electric brake device of FIG. In the description of FIG. 3, FIG. 2 will also be described with appropriate reference.
After the process starts, the reaction force correlation estimation data storage unit 29 acquires the estimated angle and the estimated reaction force as data for correlation calculation (step S1). In the example of this FIG. 3, although the example which uses an angle and reaction force as data is shown, as shown in FIG. 6, FIG. 11 mentioned later, it can be suitably changed. The parameter may be equivalent to that described above. For example, instead of the angle, a stroke amount or the like through an equivalent lead of the actuator body AH can be used.

  Next, the reaction force correlation derivation unit 28 obtains a function f of Fre = f (Th) relating the reaction force Fre and the angle Th (step S2). The function f may be a function for obtaining an angle using the reaction force as an argument in reverse to the above. The reaction force correlation deriving unit 28 evaluates an error between the correlation obtained in step S2 and the actual estimated value obtained in step S1 (step S3). The evaluation of the error is given, for example, by the root mean square of the deviation between the value calculated from the determined correlation and the actual estimated value. Alternatively, the evaluation of the error may use a root mean square or a sum of error rates, and a weighting factor or the like may be appropriately provided to focus a region of a predetermined angle or reaction force.

  The convergence operation unit 30 performs curve fitting convergence operation for adjusting the correlation in step S2 so that the error in step S3 is reduced (step S4). For the convergence operation, for example, a convergence operation method represented by the Levenberg-Marquardt method or the Gauss-Newton method can be used. When the error does not converge to the minimum value (step S4: no), the process returns to step S2.

The abnormality determination unit 31 compares the finalized convergence error (step S4: yes) with respect to a predetermined reference value (step S5), and if the error is larger than the reference value (step S5): yes), the angle estimation function unit 26 determines that it is abnormal (step S6). Thereafter, the process ends.
FIG. 3 is abbreviated to the minimum necessary flow, and a flow not described in FIG. 3 may be appropriately provided in actual operation. For example, since steps S2 to S4 can be an infinite loop, it is also possible to complete the convergence operation according to the upper limit of the number of iterations and provide a process for leaving the loop.

<Operation Example of Electric Brake Device>
FIG. 4 shows an execution example of the angle estimation abnormality detection function unit of FIG. 2 when sticking of the output of the angle sensor occurs.
As shown in FIGS. 4A and 4B, when sticking of the output of the angle sensor occurs during operation of the electric brake device, the estimated angle stops in that state. At this time, since the angle does not move, as shown in FIG. 4C, the estimated reaction force rises to a value equivalent to the maximum torque that can be exhibited by the electric motor.

  At this time, as shown in FIG. 4E, the correlation between the estimated angle and the estimated reaction force draws a locus like a broken point with high discontinuity from a continuous curve depending on the actuator stiffness. For this reason, the result of curve fitting for such a trajectory will generate a relatively large estimation error, and as shown in FIG. 4 (d), the abnormality determining unit 31 (FIG. 2) determines that this error has a predetermined threshold value. When it exceeds, it can be judged that the angle estimation function unit 26 (FIG. 2) is abnormal. In the present embodiment, for example, when angle sensorless estimation is performed, the same error estimation as in this figure is possible even when an abnormality occurs due to sticking of a register that stores observation abnormalities or estimated values of input / output or the like. It is.

  FIG. 5 shows an example in the case where the fixation of the output of the angle sensor does not occur in the example of FIG. 4 and the operation is normal. In the case of FIG. 5, the correlation between the estimated angle and the estimated reaction force describes a continuous curve locus depending on the actuator stiffness. The result of curve fitting for such trajectories does not produce large estimation errors.

<Function effect>
According to the electric brake device 1 described above, the reaction force correlation deriving unit 28 estimates the reaction force correlation to associate the acquired estimated angle with the estimated reaction force according to the defined conditions. The abnormality determination unit 31 evaluates the degree of coincidence between the estimated reaction force correlation and the original data. The abnormality determining unit 31 determines that the angle estimation function unit 26 is abnormal when the degree of coincidence falls below a predetermined reference. As described above, the abnormality in the angle estimation can be determined more inexpensively than in the prior art and also at the time of the brake operation or the like.

<Other Embodiments>
In the following description, the portions corresponding to the items described in advance in each embodiment are denoted by the same reference numerals, and the redundant description will be omitted. When only a part of the configuration is described, the other parts of the configuration are the same as those described in the preceding embodiment unless otherwise stated. The same function and effect can be obtained from the same configuration. Not only the combination of the portions specifically described in the embodiments but also the embodiments may be partially combined if any problem does not occur in the combination.

  FIG. 6 shows an example in which the convergence operation unit is not provided in FIG. In the case of FIG. 6, the reaction force correlation deriving unit 28 has a function of uniquely determining a correlation function from a predetermined estimated reaction force and an estimated angle. For example, it can be confirmed by preliminary verification that a sufficiently accurate predetermined correlation function can be obtained only by finely adjusting the correlation function from a predetermined estimated reaction force and an estimated angle without performing a convergence operation by simulation, experiment, etc. In this case, the calculation load can be reduced by the method of FIG. The error calculating unit 32 calculates an error between the calculated correlation and the actual estimated value. The abnormality determination unit 31 may determine that the angle estimation function unit 26 is abnormal when this error exceeds a predetermined threshold.

FIG. 7 shows forward operation when the electric motor of the actuator main body rotates in the pressure increasing direction, reverse operation when the electric motor rotates in the pressure decreasing direction, and hysteresis intermediate operation. The example which performs correlation estimation and abnormality judgment is shown.
After the start of this process, the control device 2 (FIG. 2 etc.) determines the motor rotation direction (step S11), and separates the conditions into the pressure increase direction, the pressure decrease direction, and zero (no rotation). The rotational direction can be determined from, for example, a motor angular velocity. Further, since it is difficult to strictly determine the zero velocity, for example, when the angular velocity is within a predetermined range such as ± 0.5 rad / s, it may be regarded as the zero velocity, and the angular velocity threshold at this time is It may be determined arbitrarily.

When the electric motor rotates in the pressure increasing direction, the reaction force correlation deriving unit 28 (FIG. 2 and the like) derives a correlation (positive operation correlation) in the positive operation (step S12). The correlation derivation process of step S12 corresponds to, for example, steps S2 to S4 of FIG.
If the error in the correlation derivation is large (step S13: yes), the abnormality determination unit 31 (FIG. 2 and the like) determines that the angle estimation is abnormal (step S16). Thereafter, the process ends.

When the electric motor is rotating in the pressure reducing direction, the reaction force correlation deriving unit 28 (FIG. 2 and the like) derives a correlation (reverse operation correlation) in reverse operation (step S14). The correlation derivation process of step S14 corresponds to, for example, steps S2 to S4 of FIG.
If the error in the correlation derivation is large (step S15: yes), the abnormality determination unit 31 (FIG. 2 or the like) determines that the angle estimation is abnormal (step S17). Thereafter, the process ends.

  At this time, depending on the specification of the actuator, it may be possible to roughly estimate the other from one of the characteristics at the time of normal operation or at the time of reverse operation. In this case, only one of the reaction force correlation estimation in step S12 in the normal operation and the reaction force correlation estimation in step S14 in the reverse operation is performed, and the conversion factor determined in the result is calculated. The other reaction force correlation is calculated, and on the other side, the error of the actual estimation result with respect to the predetermined result based on the calculated reaction force correlation is evaluated, and the case where the error is larger than a predetermined is determined as the angle estimation abnormality. It is good also as processing to do.

  When it can be considered that the electric motor is in the stopped state, the controller 2 is based on the forward operation correlation and the reverse operation correlation from the first parameter for deriving the reaction force correlation based on the forward operation correlation and the reverse operation correlation. It has a function of deriving the other second parameter. The abnormality determination unit 31 estimates the angle when the second parameter is out of the range of the second parameter group derived based on the normal operation correlation and the reverse operation correlation based on the error correction ratio. It is determined that the function unit 26 is abnormal.

In the reaction force correlation that relates the motor angle and the estimated reaction force, the motor angle is a first parameter, and the estimated reaction force is a second parameter. In the case of the hysteresis intermediate operation where the motor angular velocity is approximately zero, the upper and lower limit values (second parameter group) of the reaction force, which is the second parameter, are calculated based on the positive operation correlation and the reverse operation correlation calculated up to that point (Step S18). If the estimated reaction force exceeds the calculated reaction force from the correlation at the time of normal operation (step S19: yes), or if the estimated reaction force is smaller than the calculated reaction force at the reverse operation (step S20: yes) It is determined that the estimated reaction force, which is the second parameter, deviates from the range of upper and lower limit values of the reaction force, which is the second parameter group, and it is determined that the angle estimation is abnormal (step S21). Thereafter, the process ends.
The upper and lower limit values of the reaction force are corrected in consideration of the error of correlation estimation, and the upper and lower limit values are expanded based on a predetermined error correction ratio based on the derived upper and lower limit values so that the width consisting of the upper and lower limit values is expanded. The above determination may be performed based on upper and lower limit values obtained by expanding the width.
Also, contrary to the above, the estimated reaction force may be set as the first parameter, and the motor angle may be set as the second parameter. The situation where the estimated reaction force deviates from the upper and lower limit values of the reaction force at a predetermined angle is roughly equivalent to the situation where the estimated angle deviates from the upper and lower limit values of the angle at a predetermined reaction force.

  FIG. 8 shows an example of operation in the case where sticking of the angle sensor occurs at the time of pressure reduction in pressure increase / decrease operation by applying the method of separating reaction force correlation by dividing normal operation / reverse operation shown in FIG. When the sticking of the angle sensor occurs, the correlation between the estimated angle and the estimated reaction force draws a locus such as a break point with a high degree of discontinuity from a continuous curve dependent on the actuator stiffness. For this reason, the result of curve fitting for such a trajectory will generate a relatively large estimation error, and the abnormality judgment unit 31 (FIG. 2) determines that the angle estimation function unit is abnormal when this error exceeds a predetermined threshold. to decide. Even when sticking of the angle sensor occurs at the time of pressure increase, abnormality of the angle estimation function unit can be determined in the same manner as described above.

  FIG. 9 shows an example of applying processing for excluding data from correlation estimation when the angular acceleration of the electric motor is larger than a predetermined value. In general, when the angular acceleration is large, the estimation error of the estimated reaction force often becomes relatively large mainly due to the inertia moment error, the sliding resistance and the like. Can reduce the effects of large estimates of

  If the magnitude of the angular acceleration estimated by the angular acceleration estimation function unit 33 (FIG. 2) is smaller than a predetermined value after the start of this process (step S31: no), the reaction force correlation estimation data storage unit 29 (FIG. 2) Data for force correlation is acquired (step S32). The angular acceleration in step S31 can be obtained from, for example, estimation using output torque, estimated reaction force torque, and moment of inertia, or a second-order derivative value of estimated angle, or the like.

Further, the “magnitude” of the angular acceleration in step S31 means the magnitude as an absolute value regardless of whether it is positive or negative. The data acquired in step S32 may be the estimated reaction force and estimated angle shown in step S1 of FIG. 3, or may be other estimated stroke amount, estimated brake load, or other parameters. When the number of data is equal to or more than a predetermined number (step S33: yes), estimation of reaction force correlation and angle estimation abnormality diagnosis (steps S34 to S37) are performed. Thereafter, the process ends.
According to this configuration, the accuracy of the abnormality determination can be improved by estimating the reaction force correlation by excluding the state in which the angular velocity is large.

  In a vehicle equipped with an electric brake device, FIG. 10 performs a braking operation for exerting a braking force from a state in which a friction brake (brake) is released and performs reaction force correlation in at least one brake cycle until the friction brake is released. Estimate An example in which an angle estimation abnormality is determined from the reaction force correlation from the error between the estimated reaction force and the estimated angle at the time of the next and subsequent braking operations is shown.

  After the start of this process, the control device determines whether the friction brake is being released or in operation (step S41), and if being released, the reaction force correlation estimation data storage unit 29 (FIG. 2 etc.) The data for correlation calculation is acquired from the brake operation history of (step S45), and the reaction force correlation derivation unit 28 (FIG. 2 and the like) calculates reaction force correlation (step S46). The data acquired in step S45 may be the estimated reaction force and estimated angle shown in step S1 of FIG. 3, or may be other estimated stroke amount, estimated brake load, and other parameters.

  At this time, for example, when only a very low brake load is exhibited, there may be cases where it is not sufficient to calculate the reaction force correlation. For example, when at least a predetermined brake load is exerted. The process of steps S46 to S46 may be performed. The reaction force correlation calculated in step S46 may be one brake cycle from brake application to release, or may be a predetermined plurality of brake cycles.

  When the friction brake is in operation (during operation), the angle estimation abnormality detection function unit 24 (FIG. 2 and the like) is the estimated correlation and estimated angle in the current braking operation with respect to the reaction force correlation derived from the previous braking operations. An error (amount of deviation) is calculated (step S42). This calculation is performed, for example, when the predetermined function pn = fn (Thn) for obtaining the reaction force pn with respect to the angle Thn in the previous brake operations is obtained, for example, for the current estimated reaction force pt and the estimated angle Tht May be obtained by calculating Δ = | pt−fn (Tht) |, and an error rate or the like may be used instead of the simple difference as described above.

If the error is larger than the predetermined value (step S43: yes), it is determined that the angle estimation function unit is abnormal (step S44). Thereafter, the process ends.
According to this configuration, even when processing in real time is difficult due to a problem such as calculation load, it is possible to estimate an abnormality of the angle estimation function unit using the correlation at the time of braking.

  FIG. 11 shows an example of using an estimated weight instead of the estimated angle with respect to FIG. FIG. 12 shows an example using the correlation between the estimated reaction force and the estimated load (estimated brake load). In general, the relationship between the load and the reaction force exhibits a relatively monotonous correlation, which facilitates the derivation of the correlation function. According to the configurations shown in FIGS. 11 and 12, the reaction force correlation between the estimated reaction force and the estimated load is not affected by the non-linear stiffness of the actuator body AH, so that the correlation can be set relatively easily. In the case of this configuration, the load estimation function unit 19 is limited to the function of estimating the load using the load sensor Sb.

  If the abnormality determination unit 31 determines that the angle estimation function unit 26 is abnormal, the abnormality determination unit 31 transmits the fact that the angle estimation result is abnormal to the various control function units, and each control function unit determines the angle It is good also as a specification which performs predetermined safe operation, when presumed abnormality occurs. For example, the operation of the electric brake device 1 may be continued by the control method of the electric motor 4 which does not use the angle estimation result.

  Specifically, for example, the control device 2 does not depend on the actual angle of the electric motor 4 but on the deviation between the brake force estimated value obtained from the estimated load estimated by the load estimation function unit 19 and the brake force command value. Based on this, the current phase of the electric motor 4 is determined. The control device 2 obtains the calculated electrical angular velocity from the deviation between the estimated braking force value and the brake force command value, and obtains the motor current from the calculated electrical angle determined from the calculated electrical angular velocity. The control device 2 causes the motor current or the like determined from the calculated electrical angle to follow the motor current target value determined from the determined current phase or the like.

  Alternatively, when an abnormality occurs in the angle estimation function unit 26, the control device 2 may perform a process of stopping energization of the electric motor 4, and these processes may be appropriately performed based on safety design requirements in the vehicle. It shall be selectable.

  As a conversion mechanism portion of the linear motion mechanism 6, various screw mechanisms such as a planetary roller and a ball screw, a mechanism utilizing an inclination of a ball lamp or the like, and the like can be used.

  As mentioned above, although the form for implementing this invention was demonstrated based on embodiment, embodiment disclosed this time is an illustration and restrictive at no points. The scope of the present invention is indicated not by the above description but by the claims, and is intended to include all modifications within the meaning and scope equivalent to the claims.

2 ... Control device 4 ... Electric motor 6 ... Linear motion mechanism (friction material operation means)
8 Brake rotor 9 Friction material 19 Load estimation functional unit 24 Angle estimation abnormality detection functional unit 25 Angular velocity estimation functional unit 26 Angle estimation functional unit 27 Reaction force estimation functional unit 28 Reaction force correlation derivation unit 29 Reaction force correlation estimation data storage unit (data acquisition unit)
31 ... abnormality determination unit 33 ... angular acceleration estimation function unit

Claims (9)

A brake rotor, a friction material that contacts the brake rotor to generate a braking force, an electric motor, friction material operation means that converts the output of the electric motor to a pressing force of the friction material, and the electric motor are controlled An electric brake device comprising:
The controller is
An angle estimation function unit for estimating the angle of the electric motor;
A reaction force estimation function unit that estimates a reaction force due to a reaction of the pressing force of the friction material;
An angle estimation abnormality detection function unit that determines presence or absence of an abnormality of the angle estimation function unit;
The angle estimation abnormality detection function unit
A data acquisition unit that acquires, as data, an estimated angle that is an angle estimated by the angle estimation function unit or a parameter equivalent to the estimated angle, and an estimated reaction force that is a reaction force estimated by the reaction force estimation function unit;
A reaction force correlation deriving unit that estimates a reaction force correlation that associates the estimated angle or the parameter acquired by the data acquisition unit with the estimated reaction force according to a defined condition;
When the degree of coincidence between the reaction force correlation estimated by the reaction force correlation derivation unit and the data acquired by the data acquisition unit falls below a defined reference, the angle estimation function unit is determined to be abnormal. An electric brake device having an abnormality determination unit. The electromotive brake device according to claim 1, wherein the reaction force correlation deriving unit has, as the determined condition, a reference correlation function that associates the estimated angle or the parameter with the estimated reaction force, and the reference correlation function It has a function of deriving the reaction force correlation that substantially minimizes an evaluation index based on an error between a function and data acquired by the data acquisition unit,
The abnormality estimation unit determines that the angle estimation function unit is abnormal when an evaluation index based on the error at the time of estimation of the reaction force correlation is evaluated corresponding to a state in which the error is larger than a predetermined amount. An electric brake device that is judged to be present. The electric brake device according to claim 1, wherein the reaction force correlation exerts a braking force from a state where the brake is released, and the estimated angle and the estimated angle in a first brake cycle until the brake is released again. It is a reaction force correlation that relates the force,
The abnormality determination unit is configured to execute the estimated angle and the first estimated reaction force during a second brake cycle that is performed after the first brake cycle and causes the brake force to be exerted from the released state of the brake. The electric brake system, wherein the angle estimation function unit is determined to be abnormal when the deviation amount with respect to the reaction force correlation determined during the brake cycle is larger than a predetermined amount. The electric brake system according to any one of claims 1 to 3, wherein the control device has an angular velocity estimation function unit for estimating the angular velocity of the electric motor, and the angular velocity estimated by the angular velocity estimation function unit. Based on the estimated angular velocity, it is determined whether the electric motor is rotating in the direction of increasing or decreasing the pressing force of the friction material,
The reaction force correlation deriving unit, as the reaction force correlation, a positive operation correlation when the electric motor is rotating in the pressure rising direction, and a reverse operation correlation when the electric motor is rotating in the pressure decreasing direction Have a function to estimate
The abnormality determination unit is configured to match the degree of coincidence of the positive operation correlation when the electric motor is rotating in the boosting direction and the degree of coincidence of the reverse operation correlation when the electric motor is rotating in the step-down direction. The electric brake device, which determines that the angle estimation function unit is abnormal, when one or both of the coincidence degree falls below a defined reference. The electric brake system according to any one of claims 1 to 3, wherein the control device has an angular velocity estimation function unit for estimating the angular velocity of the electric motor, and the angular velocity estimated by the angular velocity estimation function unit. And has a function of determining whether the electric motor is rotating in the direction of increasing or decreasing the pressing force of the friction material, based on the estimated angular velocity.
The reaction force correlation deriving unit estimates either one of a positive operation correlation when the electric motor is rotating in the pressure rising direction and a reverse operation correlation when the electric motor is rotating in the pressure decreasing direction. And the function of estimating the correlation of the other through a defined conversion factor based on the correlation of any one of the estimated positive-working correlation or reverse-working correlation,
The abnormality determination unit is configured to match the degree of coincidence of the positive operation correlation when the electric motor is rotating in the boosting direction and the degree of coincidence of the reverse operation correlation when the electric motor is rotating in the step-down direction. The electric brake device which judges that the said angle estimation function part is abnormal, when the coincidence degree of any one or both falls below the defined reference | standard. The electric brake device according to claim 4 or 5, wherein the control device has a function of regarding the electric motor as being in a stop state when the estimated angular velocity is smaller than a predetermined magnitude.
In the case where it can be considered that the electric motor is in a stopped state, the control device is configured to calculate the positive operation correlation from one of the first parameters for deriving the reaction force correlation based on the positive operation correlation and the reverse operation correlation. And a function of deriving the other second parameter based on the inverse operation correlation,
When the second parameter is out of the range expanded based on the error correction ratio from the range of the second parameter group derived based on the normal operation correlation and the reverse operation correlation, the abnormality determination unit An electric brake device that determines that the angle estimation function unit is abnormal. The electric brake device according to any one of claims 1 to 6, wherein the reaction force correlation deriving unit is based on the rigidity of the component of the electric brake device including the friction material as the determined condition. A first combined function f1 of the reaction force and the angle including the variable stiffness parameter α that changes the stiffness, and the stiffness of components of the electric brake device other than the above-described components included in the first combined function f1 And a deformation ratio β between a component related to the first combination function f1 and a component related to the second combination function f2 based on And for the estimated angle or estimated position x
An electric brake system having a function of determining the variable stiffness parameter α and the deformation ratio β so as to minimize the variance of the calculation error due to p = f1 (α, βx) + f2 ((1−β) x). The electric brake device according to any one of claims 1 to 6, wherein the control device has a load estimation function unit for estimating a pressing force of the friction material,
The reaction force correlation is a reaction force correlation that associates an estimated load, which is a pressing force estimated by the load estimation function unit, with the estimated reaction force,
The abnormality determination unit determines that the angle estimation function unit is abnormal when the degree of coincidence between the reaction force correlation and the data acquired by the data acquisition unit falls below a predetermined reference. apparatus. The electric brake system according to any one of claims 1 to 8, wherein the control device has an angular acceleration estimation function unit for estimating an angular acceleration of the electric motor or a value corresponding to the angular acceleration. And
The said reaction force correlation derivation | leading-out part estimates the said reaction force correlation using the estimated reaction force and estimated angle in conditions smaller than the magnitude | size in which the presumed angular acceleration estimated by the said angular acceleration estimation function part was defined.

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