JP2010111254A - Electric power steering control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electrical power steering control device capable of supplying an accurate assisting force corresponding to a steering sense that a driver feels and obtaining a satisfactory steering feeling. <P>SOLUTION: A differential command value T<SB>1</SB>is calculated based on the steering torque T of a steering, a differential gain g and a first current command value I<SB>1</SB>are calculated based on the steering torque T and the vehicle speed V, a convergence value AS is calculated based on the vehicle speed V and the rotation speed RE of a motor, a gain G is calculated based on the steering torque T and the angular velocity AV, a second current command value I<SB>2</SB>is calculated based on the differential command value T<SB>1</SB>and the differential gain g, a convergence command value as is calculated based on the convergence value AS and the gain G, a third current command value I<SB>3</SB>is calculated based on the first current command value I<SB>1</SB>and the second current command value I<SB>2</SB>, a drive current command value I<SB>d</SB>is calculated based on the third current command value I<SB>3</SB>and the convergence command value as, and the motor is driven based on the drive current command value I<SB>d</SB>. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an electric power steering control device used in an electric power steering system.

  An electric power steering system is a system that assists a driver's steering by applying an assisting force by an electric motor during steering of a steering wheel that constitutes a steering mechanism in an automobile, for example. This system allows the driver to steer the steering with a light force.

  In such an electric power steering system, in order to improve the steering feeling of the steering, in Patent Document 1, the steering angular velocity data corresponding to the steering angle based on the output from the steering angle sensor and the output from the vehicle speed sensor are disclosed. Is stored a predetermined number of times within a predetermined time, and after deleting the upper limit and the lower limit of the stored data, the average speed and the average steering angular speed are calculated based on the remaining data. The driver's characteristics are determined by comparing the calculated average speed and average steering angular speed with a standard steering pattern stored in advance. And based on the said determination, an electric motor is controlled by the controller which has a standard assist pattern, and assist force is exhibited.

  Further, in Patent Document 2, a steering assist command value is calculated based on the steering torque and the vehicle speed, a current control value is calculated from the steering assist command value and the motor current value, and the motor output current and the terminal voltage are calculated. The angular velocity of the motor (steering angular velocity) is estimated from this, and the angular velocity is multiplied by a constant with a predetermined gain corresponding to the angular velocity of the motor to obtain a convergence signal (convergence control value). Then, the steering state of the steering is detected from the angular velocity of the motor and the output current. When the angular velocity of the motor is equal to or higher than a predetermined value and the output current is equal to or higher than the predetermined value, the gain is switched, and the convergence signal is subtracted from the current control value. The motor is driven by the command value obtained in this way.

  In Patent Document 3, the assist current value is determined based on the output of the torque sensor that detects the steering torque of the steering wheel and the output of the vehicle speed sensor that detects the vehicle speed, and the differential gain is determined by the output of the torque sensor and the vehicle speed. Thus, within a predetermined steering torque range, when the vehicle speed is 0, the differential command value is determined by multiplying the differential gain, which is small when neutral and increases as the steering torque increases, with the differential amount of the torque sensor output. To do. Then, the assist motor is driven by adding the differential command value to the assist current value, and the assist torque is added to the steering torque.

  In Patent Document 4, in order to accurately recognize the operational feeling felt by the driver, a two-dimensional model is shown in which the horizontal axis represents the torque sensor value applied to the steering device and the vertical axis represents the rotational value of the assist motor. Sensitivity areas as areas of each sensitivity index are set in the graph, and a sensitivity identification map in which the sensitivity areas are set is provided for each vehicle speed value and stored in the storage unit. Then, by referring to the sensitivity identification map based on the input vehicle speed value, torque sensor value, and rotation value, a sensitivity index indicating the steering feeling felt by the driver at each time point is output.

Japanese Patent No. 3222506 Japanese Patent No. 3637714 Japanese Patent No. 3809594 JP 2007-276708 A

  By the way, in the electric power steering system, the electric motor rotates in accordance with a preset control program, and the auxiliary force is supplied to the steering by the rotational force of the electric motor. However, at present, since a control program that can supply an assisting force that matches the steering feeling felt by the driver is not sufficiently realized, it is easy for the driver to feel uncomfortable in steering, and the steering feeling. May get worse.

  In view of the above-described problems, the present invention provides an electric power steering control device that can supply an appropriate assisting force according to a steering feeling felt by a driver to improve steering feeling. The purpose is that.

  An electric power steering control device according to the present invention includes a steering torque input means for inputting a steering torque of a steering mechanism of a vehicle, an angular speed input means for inputting a rotational angular speed of the steering mechanism, and a vehicle speed input for inputting the vehicle speed of the vehicle. Based on inputs from the means, rotational speed input means for inputting the rotational speed of the motor for applying assisting force to the steering mechanism, steering torque input means, angular speed input means, vehicle speed input means, and rotational speed input means. Drive current command value output means for outputting a drive current command value for driving, the drive current command value output means, differential command value calculation means for differentiating the steering torque and calculating a differential command value, Differential gain calculating means for calculating a differential gain that is a gain for the differential command value based on the steering torque and the vehicle speed; and a first current index based on the steering torque and the vehicle speed. Determining a steering sensation of the steering mechanism based on a steering torque and a rotational angular velocity; a first current command value calculating means for calculating a value; a convergent value calculating means for calculating a convergent value based on the vehicle speed and the rotational speed; A convergence gain calculating means for calculating a convergence gain that is a gain for the convergence value based on the determination result; a second current command value calculating means for calculating a second current command value by multiplying the differential command value and the differential gain; A convergence command value calculating means for calculating the convergence command value by multiplying the convergence value and the convergence gain, and a third current command value by adding the first current command value and the second current command value. Current command value calculating means; and drive current command value calculating means for calculating a drive current command value by subtracting the convergence command value from the third current command value.

  In this way, unlike the conventional technology that changes only the assist current value and the differential command value according to the steering torque and the vehicle speed, the drive current command value for driving the motor is finely controlled, and its adjustment accuracy Therefore, the driving force of the motor can be finely adjusted as compared with the prior art. As a result, it is possible to supply an appropriate auxiliary force (motor driving force) according to the steering sensation felt by the steering operator, so that the steering feeling can be improved.

  In the electric power steering control device of the present invention, the convergence gain calculating means determines a steering sensation corresponding to each steering torque and rotational angular velocity from a plurality of steering sensations classified based on the steering torque and the rotational angular velocity. And a convergence gain determination unit that determines a convergence gain corresponding to the determination result based on the determination result by the first determination unit.

  By doing in this way, unlike the prior art that determines the steering sensation in association with the rotational speed of the motor, the rotational speed of the motor is not used for determination of the steering sensation. There is no need to tune for steering feel determination. For this reason, complicated tuning is not required, and the cost can be reduced. Further, since it is not necessary to input an adjustment value for the steering sensation by the steering hand, which has been performed in the past, it is possible to save the trouble of inputting the adjustment value.

  In the electric power steering control device of the present invention, when there are a plurality of steering sensations corresponding to the steering torque and the rotational angular velocity, the first determination means determines which of the plurality of steering sensations according to a predetermined priority order. Such steering feeling may be used as the determination result.

  By doing in this way, even when there are a plurality of steering senses corresponding to the steering torque and the rotational angular velocity, any one of the steering senses can be set as the determination result by the first determination means according to the priority order. System errors can be suppressed.

  In the electric power steering control device of the present invention, the convergence gain calculating means determines whether or not the steering sensation of the steering mechanism corresponds to a specific steering sensation based on the steering torque, the differential command value, and the vehicle speed. You may have a 2nd determination means. Then, if the determination result by the second determination means is applicable, it is verified whether there are a plurality of steering feelings determined by the first determination means. If there are a plurality of steering feelings, the second determination means It is verified whether or not the specific steering sensation matches any of the plurality of steering sensations by the first determination means. If there is a matching steering sensation, the matching steering sensation is determined as the steering sensation of the steering mechanism. May be.

  By doing in this way, in order to finally determine the steering sensation based on the determination result by the first determination unit and the determination result by the second determination unit, the steering sensation felt by the steering hand is more accurately specified. I can do it. Thereby, the uncomfortable feeling of the steering feeling felt by the steering operator can be further reduced, and thus the steering feeling can be improved.

  In the electric power steering control device of the present invention, the current gain calculating means is different between a first determination result that is a determination result by the first determination means and a second determination result that is a determination result subsequent to the first determination result. If not, the steering sensation of the steering mechanism is determined based on the second determination result, and the first determination result is different from the second determination result, and the same determination result as the second determination result is 2 If the predetermined number of times has not been obtained continuously after the determination result, the steering sensation of the steering mechanism is determined based on the first determination result, and the first determination result and the second determination result are different, and When the same determination result as the second determination result is continuously obtained a predetermined number of times after the second determination result, the steering sensation of the steering mechanism may be determined based on the second determination result.

  By doing in this way, even when the determination result by a 1st determination means changes frequently, it can suppress that a steering feeling is changed frequently based on the said determination result. Thereby, the uncomfortable feeling of the steering feeling felt by the steering operator can be further reduced, and thus the steering feeling can be improved.

  In the electric power steering control device of the present invention, a filter unit that smoothes a change in gain output from the convergence gain calculation unit may be provided between the convergence gain calculation unit and the convergence command value calculation unit.

  By doing in this way, the rapid change of the gain based on the change of steering feeling can be suppressed. As a result, a sudden change in the drive current command value for driving the motor can be suppressed, so that the steering feeler does not feel a sense of discomfort in the steering feeling when switching the steering sense. .

  According to the present invention, the steering sensation of the steering mechanism determined based on the steering torque, the rotational angular velocity of the steering mechanism, the vehicle speed, the rotational parameter of the motor that gives auxiliary force to the steering mechanism, and the steering torque and the rotational angular velocity. Based on this, since the drive current command value for driving the motor is calculated, the drive current command value can be finely controlled to increase the adjustment accuracy. As a result, it is possible to supply an appropriate auxiliary force (motor driving force) according to the steering sensation felt by the steering operator, so that the steering feeling can be improved.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 to 2, 8 to 9, and 12 to 13, the same or corresponding parts are denoted by the same reference numerals.

  FIG. 1 is a diagram showing an electric power steering system 100 which is an embodiment of the present invention and includes an electric power steering control device (for example, FIG. 2) described later. The electric power steering system 100 is mounted on a vehicle (for example, an automobile).

  In the electric power steering system 100 in the figure, when the steering 1 is steered (rotated), the steering force is transmitted to the gear mechanism 3 via the shaft 2a, and further the shaft via the shaft 2b and the gear mechanism 5. 6 is transmitted. The shaft 6 is driven by the steering force. When the shaft 6 is driven, the direction of the wheel 8 is changed via the link mechanism 7.

  When the motor 15 rotates, the driving force is transmitted to the gear mechanism 3 via the clutch 4 and further transmitted to the shaft 6 via the shaft 2 b and the gear mechanism 5. Thereby, in addition to the steering force transmitted by the steering of the steering 1, the driving force of the motor 15 is also transmitted to the shaft 6, so that the driving of the shaft 6 and the turning of the wheels 8 are assisted by the driving force. . That is, steering by the steering 1 is assisted by the motor 15. In addition, the motor 15 in this embodiment consists of a brush motor, for example.

  The torque sensor 11 detects a steering torque applied by the steering 1. The angular velocity sensor 12 detects the angular velocity (rotational operation speed) of the steering 1. The vehicle speed sensor 13 detects the vehicle speed (traveling speed) of the vehicle. The motor rotation sensor 14 detects the rotation speed of the motor 15. Here, the rotation speed per unit time can be used instead of the rotation speed. However, if the rotation speed is known, the rotation speed is also known. Therefore, detecting the rotation speed is substantially equivalent to detecting the rotation speed. Are the same. Therefore, the rotational speed in the present invention is a concept including the rotational speed. The torque sensor 11 is an embodiment of the steering torque input means in the present invention, the angular velocity sensor 12 is an embodiment of the angular speed input means in the present invention, and the vehicle speed sensor 13 is the vehicle speed input means in the present invention. The motor rotation sensor 14 is an embodiment of the rotational speed input means in the present invention.

  An ECU (Electronic Control Unit) 10 controls the clutch 4 to be ON (coupled) / OFF (disengaged). The ECU 10 determines a current command value for driving the motor 15 based on the steering torque detected by the torque sensor 11, the angular velocity detected by the angular velocity sensor 12, and the vehicle speed detected by the vehicle speed sensor 13, and the current command The drive of the motor 15 is controlled based on the value. The ECU 10 is an embodiment of the drive current command value output means in the present invention.

  The battery 9 supplies electric power to the ECU 10 and the motor 15. The ECU 10, the torque sensor 11, the angular velocity sensor 12, the vehicle speed sensor 13, and the motor rotation sensor 14 constitute an embodiment of the electric power steering control device according to the present invention.

  2, 9, and 12 to 13 are diagrams showing functional blocks of the ECU 10, and a portion surrounded by an alternate long and short dash line (except for the motor driving unit 51) in each drawing is an internal part of the ECU 10. Is a function executed by the program.

  FIG. 2 is a diagram showing functional blocks of the ECU 10 in the first example of the present embodiment. Similarly, FIG. 9 shows the second example, FIG. 12 shows the fifth example, and FIG. 13 shows the sixth example. It is a figure which shows an Example. The third and fourth embodiments are not shown (details will be described later).

  First, the ECU 10 (first embodiment) shown in FIG. 2 will be described. The steering torque T of the steering 1 (FIG. 1) detected by the torque sensor 11 is input to a differential command value calculator 21, a differential gain calculator 22, a first current command value calculator 23, and a convergence gain calculator 25a. .

  The angular velocity AV of the steering 1 detected by the angular velocity sensor 12 is input to the convergence gain calculator 25a. The vehicle speed V of the vehicle detected by the vehicle speed sensor 13 is input to the differential gain calculator 22, the first current command value calculator 23, and the convergence value calculator 24. The rotational speed RE of the motor 15 detected by the motor rotation sensor 14 is input to the convergence value calculator 24.

The differential command value calculator 21 calculates the differential command value T ₁ by differentiating the steering torque T with respect to time, and outputs it to the multiplier 31. The differential gain calculator 22 calculates a differential gain g that is a gain for the differential command value T ₁ based on the steering torque T and the vehicle speed V, and outputs the differential gain g to the multiplier 31. Specifically, the differential gain calculator 22 stores in advance three types of differential gain curves (FIG. 3) that vary depending on the vehicle speed V. The differential command value calculator 21 constitutes an embodiment of the differential command value calculation means in the present invention.

In the differential gain curve shown in FIG. 3, the differential gain g when the vehicle speed V is V ₀ (eg, V ₀ = 0: when the vehicle is stopped) (solid line) is constant regardless of the value of the steering torque T. When the vehicle speed V is V ₁ (for example, V ₁ = 10: when the vehicle is running) (dotted line), the differential gain g decreases as the value of the steering torque T increases. Similarly, the vehicle speed V is V _{2 (e.g.,} V 2 ₌ 20: when vehicle is traveling) differential gain g when it is (dashed line) becomes smaller as the value of the steering torque T increases.

Regardless of the value of the steering torque T, the differential gain g when the vehicle speed V is V ₀ is always larger than the differential gain g when the vehicle speed V is V ₁ and V ₂ , and the vehicle speed V is V _1. the differential gain g of the case where is always larger than the differential gain g when the vehicle speed V is V _2.

  The differential gain calculator 22 selects one of the differential gain curves according to the vehicle speed V, and calculates the differential gain g from the differential gain curve and the steering torque T. The differential gain calculator 22 constitutes an embodiment of differential gain calculation means in the present invention.

The first current command value calculator 23 (FIG. 2) calculates a first current command value I ₁ based on the steering torque T and the vehicle speed V, and outputs it to the adder 33. Specifically, the first current command value calculator 23 stores in advance three types of first current command value curves (FIG. 4) that vary depending on the vehicle speed V. The first current command value calculator 23 constitutes an embodiment of the first current command value calculation means in the present invention.

In the first current command value curve shown in FIG. 4, when the vehicle speed V is V ₀ (eg, V ₀ = 0: when the vehicle is stopped) (solid line), the first current command value I ₁ has a predetermined steering torque T. increases to a value T _0, becomes constant exceeds the predetermined value T _0. Similarly, the vehicle speed V is _{V 1 (e.g.,} V 1 = 10: when vehicle is traveling) first current command value _{I 1} when it is (dotted line) increases until the steering torque T becomes a predetermined value _{T 1} , becomes constant exceeds the predetermined value T _1. Vehicle speed V is _{V 2 (e.g.,} V 2 = 20: when vehicle is traveling) first current command value _{I 1} when it is (chain line) is increased to the steering torque T becomes a predetermined value _{T 2,} the predetermined becomes constant exceeds a value T _2. In the present embodiment, the relationship between the predetermined values T ₀ , T ₁ , and T ₂ described above is T ₀ ≦ T ₁ ≦ T ₂ and T ₀ > 0.

Further, regardless of the value of the steering torque T, the first current command value I ₁ when the vehicle speed V is V _0, rather than the first current command value I ₁ when the vehicle speed V is V _1, V ₂ always greater, the first current command value I ₁ when the vehicle speed V is V _1, the vehicle speed V is set to be always larger than the first current command value I ₁ when it is V _2.

The first current command value calculator 23 selects one of the first current command value curves according to the vehicle speed V, and calculates the first current command value I ₁ from the first current command value curve and the steering torque T. To do.

  The convergence value calculator 24 (FIG. 2) calculates a convergence value AS based on the vehicle speed V and the rotation speed RE of the motor 15 and outputs it to the multiplier 32. Specifically, the convergence value calculator 24 includes a first viscosity value curve (FIG. 5) showing the relationship between the vehicle speed V and the viscosity (convergence strength) related to the vehicle speed V, the rotational speed RE of the motor 15, and the rotational speed. A second viscosity value curve (FIG. 6) showing the relationship with the viscosity (convergence strength) related to RE is stored in advance. The convergence value calculator 24 constitutes an embodiment of the convergence value calculation means in the present invention.

In the first viscosity value curve shown in FIG. 5, when the vehicle speed V is 0, the first viscosity value K _x is a predetermined value K ₀ that is greater than ₀ , and is once until the vehicle speed V reaches the predetermined value V _0. Decrease. When the vehicle speed V exceeds a predetermined value V _0, becomes constant at K ₁ is a predetermined value of at the predetermined value V ₀ to a predetermined value V _1, the vehicle speed V exceeds a predetermined value V _1, It increases again until a predetermined value V _2. When the vehicle speed V exceeds a predetermined value V _2, again becomes constant at K ₂ is a predetermined value of at the predetermined value V _2. The relationship between the predetermined values V ₀ , V ₁ , V ₂ of the vehicle speed V described above is V ₀ <V ₁ <V ₂ and V ₀ > 0. Further, the relationship between the predetermined values K ₀ , K ₁ , and K ₂ of the first viscosity value K _x described above is K ₁ <K ₀ ≦ K ₂ and K ₁ > 0.

In the second viscosity value curve shown in FIG. 6, the second viscosity value K _y is K _y = 0 until the rotational speed RE of the motor 15 changes from 0 to a predetermined value RE _0, and from the predetermined value RE ₀ to the predetermined value. It increases up to RE ₁ and becomes constant when it exceeds the predetermined value RE ₀ . Here, the second viscosity value K _y when the rotational speed RE is the predetermined value RE ₀ is K ₃ . Note that RE ₀ > 0 and K ₃ > 0.

The convergence value calculator 24 calculates (determines) the first viscosity value K _x from the first viscosity value curve (FIG. 5) based on the vehicle speed V, and based on the rotational speed RE of the motor 15, the second viscosity value. The second viscosity value _Ky is calculated (determined) from the value curve (FIG. 6), and the first viscosity value _Kx and the second viscosity value _Ky are multiplied to calculate the convergence value AS.

  The convergence gain calculator 25 a (FIG. 2) calculates (determines) a gain G that is a gain with respect to the convergence value AS and outputs the gain G to the multiplier 32. Specifically, the convergence gain calculator 25a includes a classification map 71 (FIG. 7A) that classifies the steering sensation felt by the driver based on the steering torque T and the angular velocity AV, and the classification map 71. A correspondence table 72 (FIG. 5B) in which an identifier (hereinafter referred to as “ID”) related to a determination result and a gain value (gain G) are associated with each other is stored in advance. The convergence gain calculator 25a is an embodiment of the convergence gain calculation means according to the present invention, the classification map 71 is an embodiment of the first determination means in the present invention, and the correspondence table 72 is the present invention. It is one Embodiment of the gain determination means in. The gain G corresponds to the convergence gain in the present invention.

  The classification map 71 shown in FIG. 7A includes, for example, a steering sensation A (region in a broken line), a steering sensation B (region in a solid line), a steering sensation C (region in a one-dot chain line), Four types of steering senses with different steering senses D that do not belong to any of the steering senses A to C are distributed.

  Further, the IDs described above are set in advance for each steering sense (A to D). For example, the ID when the determination result is the steering sense A is ID = 0. Similarly, the ID when the determination result is the steering sensation B is ID = 1, the ID when the determination is the steering sensation C is ID = 2, and the ID when the determination result is the steering sensation D is ID = 3.

In this manner, the steering feeling felt by the driver is determined based on the steering torque T and the angular velocity AV, and the correspondence table 72 shown in FIG. 7B is referred to based on the ID related to the determination result. Thus, the gain G is calculated (determined). For example, the steering torque T is _{T A,} the determination results in the case the angular velocity AV is AV _A is the steering sense A, the ID related to such a determination result is 0, the correspondence table 72, the ID ( A gain G (G = a) corresponding to ID = 0) is calculated.

Similarly, the steering torque T is T _B, for the determination results in the case the angular velocity AV is AV _B is the steering sense B, ID related to the determination result is 1, the correspondence table 72, the A gain G (G = b) corresponding to ID (ID = 1) is calculated.

Steering torque T is _{T C,} the determination results in the case the angular velocity AV is AV _C is the steering sense C, the ID related to such a determination result is two, the correspondence table 72, the ID (ID = A gain G (G = c) corresponding to 2) is calculated.

Steering torque T is _{T D,} the determination results in the case the angular velocity AV is AV _D is the steering sense D, and the ID related to such a determination result is three, the correspondence table 72, the ID (ID = A gain G (G = d) corresponding to 3) is calculated.

  When the steering sensation is difficult to determine by the above-described method, that is, in the classification map 71, the portion where the steering sensation A and the steering sensation B overlap (shaded portion), or the portion where the steering sensation B and the steering sensation C overlap. When determining the steering sensation of (gray portion), in this embodiment, priority is given to the steering sensation on the front (not hidden) of the classification map 71.

  Specifically, when determining the steering sensation of the portion (shaded portion) where the steering sensation A and the steering sensation B overlap, the steering sensation B positioned in front of the steering sensation A in the classification map 71 is prioritized as a determination result. And a gain G (G = b) corresponding to the ID (ID = 1) is calculated. Similarly, when determining the steering sensation of the portion where the steering sensation B and the steering sensation C overlap (gray portion), the steering sensation B positioned in front of the steering sensation C in the classification map 71 is prioritized as a determination result. And a gain G (G = b) corresponding to the ID (ID = 1) is calculated.

Multiplier 31 (FIG. 2) calculates the second current command value I ₂ by multiplying the differential command value T ₁ and the differential gain g, and outputs to the adder 33 (FIG. 2). Multiplier 32 (FIG. 2) calculates convergence command value as by multiplying convergence value AS and gain G, and outputs the result to subtractor 34 (FIG. 2). The adder 33 calculates the third current command value I ₃ by adding the second current command value I ₂ to the first current command value I ₁ and outputs it to the subtractor 34. Subtractor 34 calculates the drive current command value I _d by subtracting the convergence command value as the third current command value I _3, and outputs to the motor driver 51. The multiplier 31 is an embodiment of the second current command value calculating means in the present invention, the multiplier 32 is an embodiment of the convergence command value calculating means in the present invention, and the adder 33 is It is one embodiment of the third current command value calculating means in the invention, and the subtractor 34 is one embodiment of the drive current command value calculating means in the present invention.

FIG. 8 is a diagram showing details of the motor drive unit 51 for driving the motor 15. The motor drive unit 51 drives the motor 15 in PWM (Pulse Width Modulation) control on the basis of the drive current command value _{I d} to be input to the FET (Field Effect Transistor) gate drive circuit 52 to be described later.

Specifically, the motor drive unit 51 includes an FET gate drive circuit 52, a boost power source 53, an H bridge circuit including FETs 61 to 64, and the like. FET gate driving circuit 52 drives the gate of each FET61~64 based on the drive current command value _{I d.}

FET61 or FET62, when driving the motor 15, the ON / OFF switched by the PWM signal of a predetermined duty ratio determined based on the drive current command value _{I d.} The FET 63 or FET 64 is turned on when the motor 15 is driven. The FETs 61 to 64 to be driven are switched according to the rotation direction of the motor 15 determined from the sign of the PWM signal.

For example, when the FET 64 is ON, by ON / OFF control of the FET 61, current levels according to the drive current command value _{I d} is, from the power source 54 FET 61, through the motor 15, FET 64, and the resistor 66 Then, the motor 15 is driven to rotate in the forward direction.

Further, when the FET 63 is ON, by ON / OFF control of the FET 62, current levels according to the drive current command value _{I d} is, from the power source 54 FET 62, through the motor 15, FET 63 and resistor 65, The motor 15 is driven to rotate in the reverse direction.

Thus, in the first embodiment of the present embodiment, ECU 10 (Fig. 2) calculates the differential command value T ₁ based on the steering torque T of the steering wheel 1 (Fig. 1), the steering torque T and the vehicle speed V Based on this, the differential gain g and the first current command value I ₁ are calculated, the convergence value AS is calculated based on the vehicle speed V and the rotational speed RE of the motor 15, and the gain G is calculated based on the steering torque T and the angular speed AV. Calculated.

Then, the second current command value I ₂ is calculated based on the differential command value T ₁ and the differential gain g, the convergence command value as is calculated based on the convergence value AS and the gain G, and the first current command value I The third current command value I ₃ is calculated based on ₁ and the second current command value I _2, and the drive current command value I _d is calculated based on the third current command value I ₃ and the convergence command value as Yes.

Therefore, unlike the first current command value I ₁ and the prior art of changing only the differential command value T ₁ according to the steering torque T and vehicle speed V, the motor 15 driving current command value for driving (Fig. 1) and finely control the I _d, since it is possible to increase the adjustment accuracy, the driving force of the motor 15 is also tunable to become compared with the prior art. Thereby, since it is possible to supply an accurate assisting force (driving force of the motor 15) according to the steering feeling felt by the driver, the steering feeling of the steering wheel 1 can be improved. In addition, a good steering feeling can be obtained even in an emergency steering state of the steering wheel in the case of danger avoidance or the like.

  Also, as a means for determining the steering sensation of the steering 1, unlike the prior art that uses the rotational speed of the motor 15 as one of the parameters, in the present embodiment, the rotational speed of the motor 15 is determined as a steering sensation. Since it is not used for the determination ((a) of FIG. 7), it is not necessary to change the setting (tuning) of the electric power steering system 100 according to the number of rotations of the motor 15 that is different for each vehicle.

  Furthermore, unlike the prior art that has an adjustment value input unit for adjusting the steering feeling, the driver does not need to input an adjustment value for adjusting the steering feeling, reducing the driver's trouble. I can do it.

  Next, the ECU 10 (second embodiment) shown in FIG. 9 will be described. In this figure, the differential command value calculator 21, differential gain calculator 22, first current command value calculator 23, convergence value calculator 24, multiplier 31, multiplier 32, adder 33, subtractor 34, The motor drive unit 51 is the same as those in the above-described ECU 10 (FIG. 2, the first embodiment) and has the same function. Therefore, description thereof will be omitted below.

  The convergence gain calculator 25b in FIG. 9 includes the steering torque T of the steering 1 (FIG. 1) detected by the torque sensor 11, as in the convergence gain calculator 25a (FIG. 2) in the first embodiment described above. The angular velocity (rotational operation speed) AV of the steering 1 detected by the angular velocity sensor 12 is input. The convergence gain calculator 25b is an embodiment of the convergence gain calculation means in the present invention.

In addition to this, the vehicle speed V of the vehicle detected by the vehicle speed sensor 13, also differential command value T ₁ are inputted. Here, the differential command value T ₁ is a value calculated by the differential command value calculator 21 by differentiating the steering torque T with respect to time, as in the first embodiment.

  The convergence gain calculator 25b calculates (determines) a gain G that is a gain with respect to the convergence value AS, and outputs the same to the multiplier 32, similarly to the convergence gain calculator 25a (FIG. 2, first embodiment). Here, the convergence value AS is a value calculated by the convergence value calculator 24 based on the vehicle speed V and the rotational speed RE of the motor 15 as in the first embodiment.

Specifically, in the convergence gain calculator 25b, as in the convergence gain calculator 25a (FIG. 2), a classification map 71 (FIG. 7A) and a correspondence table 72 (FIG. 7B) are stored in advance. is stored, in addition to this, based on the steering torque T and the differential command value T ₁ and the vehicle speed V, the determination whether or not corresponding to a particular steering sense (determination) to identify sensory discrimination A graph (hereinafter simply referred to as “discrimination graph”) 74 (FIG. 10) is stored in advance. The discrimination graph 74 is an embodiment of the second determination means in the present invention.

  Here, the calculation method of the gain G in the convergence gain calculator 25b is different from the calculation method of the gain G in the convergence gain calculator 25a (FIG. 2), and will be described below.

  The convergence gain calculator 25b determines the steering sensation using the classification map 71 ((a) of FIG. 7) based on the steering torque T and the angular velocity AV. Note that the steering feeling determination method using the classification map 71 (FIG. 7A) is the same as the determination method in the convergence gain calculator 25a (FIG. 2), and thus the description thereof is omitted.

Apart from this, the convergence gain calculator 25b, based on the differential command value T ₁ and the vehicle speed V and the steering torque T, whether corresponds to a particular steering sense, determination graph 74 (Fig. 10) Determined by

  Specifically, the discrimination graph 74 is a graph for discriminating whether or not the steering sensation at each time point corresponds to a specific (important) steering sensation set in advance. A threshold value is set in advance for determining whether or not the steering sense is met. The specific steering sensation described above may be any of the steering sensations A to D ((a) in FIG. 7). However, in the present embodiment, the specific steering sensation is referred to as the steering sensation A. Follow the instructions.

To determine the graph 74, for example, the threshold value α of the steering torque T, beta and (dashed line portion), a threshold value γ of the differential command value T _1, [delta] (dotted line) is set. Note that these threshold values α to δ are sequentially changed based on the vehicle speed V.

Here, with respect to determination graph 74, the steering torque T shown by the broken line, when the differential command value T ₁ indicated by the solid line is input, in the present embodiment, for example, the steering torque T is a threshold α And the differential command value T ₁ is a value between the threshold γ and the threshold δ, that is, both the steering torque T and the differential command value T ₁ are hatched in the figure. When the value is within the unit, it is determined that the steering sense at that time is the steering sense A.

  As described above, when the steering feeling is obtained from the classification map 71 (FIG. 7A) and the discrimination graph 74 (FIG. 10), the convergence gain calculator 25b (FIG. 9), for example, FIG. In accordance with Table 75 shown in FIG. 5, the final determination of the steering feeling felt by the driver is performed. The final determination result (steering feeling) is a portion indicated by the hatched portion in FIG.

  Specifically, as shown in (1), when the determination result by the classification map 71 is the steering feeling A and the determination result by the determination graph 74 is the steering feeling A, the steering feeling finally determined is the steering feeling A. It becomes. When the discrimination result based on the discrimination graph 74 is not the steering sensation A, the steering sensation finally determined is the steering sensation A with priority given to the classification map 71.

  As shown in (2), the determination result based on the classification map 71 is the steering sensation B that is prioritized when the steering sensation A and the steering sensation B overlap (the hatched portion in FIG. 7A), and the determination graph 74 When the determination result by is the steering sensation A, the steering sensation finally determined is the steering sensation A. At this time, since the steering sensation A is included in the overlapping part of the steering sensation in the classification map 71 and the discrimination result by the discrimination graph 74 is also the steering sensation A (coincidence of the steering sensation), the discrimination result by the discrimination graph 74 Takes precedence. When the determination result by the determination graph 74 is not the steering sensation A, the steering sensation finally determined is the steering sensation B.

  As in (3), when the determination result by the classification map 71 is the steering sensation B when the steering sensation A and the steering sensation B do not overlap, and the determination result by the determination graph 74 is the steering sensation A, the final As for the steering sensation to be determined, the determination result by the classification map 71 is prioritized and becomes the steering sensation B. At this time, since the steering sense A is not included in the steering sense obtained from the classification map 71, the determination result (steering sense A) by the determination graph 74 is not prioritized. When the determination result by the determination graph 74 is not the steering sensation A, the steering sensation finally determined is the steering sensation B.

  As shown in (4), the determination result based on the classification map 71 is the steering sensation B that is prioritized when the steering sensation B and the steering sensation C overlap (gray portion in FIG. 7A). When the determination result by is the steering sensation A, the steering sensation finally determined becomes the steering sensation B by giving priority to the determination result by the classification map 71. At this time, since the steering sensation A is not included in the overlapping part of the steering sensation in the classification map 71, the discrimination result (steering sensation A) by the discrimination graph 74 is not prioritized. When the determination result by the determination graph 74 is not the steering sensation A, the steering sensation finally determined is the steering sensation B.

  As in (5), when the determination result by the classification map 71 is the steering sensation C when the steering sensation B and the steering sensation C do not overlap, and the determination result by the determination graph 74 is the steering sensation A, finally As for the steering sensation to be determined, the determination result by the classification map 71 is given priority and becomes the steering sensation C. At this time, for the same reason as (3), the discrimination result by the discrimination graph 74 is not prioritized. When the determination result by the determination graph 74 is not the steering sensation A, the steering sensation finally determined is the steering sensation C.

  As in (6), when the determination result by the classification map 71 is the steering feeling D and the determination result by the determination graph 74 is the steering feeling A, the steering feeling finally determined is the determination result by the classification map 71. Is given priority and becomes the steering sensation D. Also at this time, for the same reason as in (3), the discrimination result by the discrimination graph 74 is not prioritized. When the discrimination result based on the discrimination graph 74 is not the steering sense A, the steering sense finally determined is the steering sense D.

  The steering feeling felt by the driver is finally determined by the above determination method, and the gain G is calculated by referring to the correspondence table 72 ((b) of FIG. 7) based on the ID related to the final determination result.

The gain G calculated by the convergence gain calculator 25 b (FIG. 9) is multiplied by the convergence value AS in the multiplier 32, and the convergence command value as calculated by the multiplication is input to the subtractor 34. The subtracter 34 subtracts the convergence command value as from the third current command value I ₃ output from the adder 33. Note that, as described above, the third current command value I ₃ is a value calculated by the adder 33 based on the first current command value I ₁ and the second current command value I ₂ . Here, the first current command value I ₁ is a value calculated by the first current command value calculator 23 based on the steering torque T and the vehicle speed V, as in the first embodiment. The second current command value I ₂ is calculated by the multiplier 31 based on the differential command value T ₁ and the differential gain g calculated by the differential gain calculator 22 as in the first embodiment described above. Value.

Then, the subtracter 34, the drive current command value I _d to the convergence command value as calculated by subtracting from the third current command value I _3, and outputs to the motor driver 51. Note that the driving method of the motor drive unit 51 based on the drive current command value I _d, is the same as in the first embodiment described above, description thereof is omitted.

  As described above, in the second example of the present embodiment, the ECU 10 (FIG. 9) determines whether the steering feeling at each time point is set in advance in addition to the above-described steering feeling determination method (first example). Is determined based on the determination result based on the classification map 71 (FIG. 7A) and the determination result based on the determination graph 74. The steering feeling is finally determined. For this reason, when it corresponds to the part in which the steering sensation overlaps in the classification map 71, the optimal steering sensation can be selected. For example, in the case of (2) in FIG. 11, the original steering sensation is B according to the classification map 71, but when the steering sensation is determined as A by the discrimination graph 74, it is corrected from B to A. Therefore, the steering sensation matches the specific steering sensation A and becomes more optimal. Thus, by using the classification map 71 and the discrimination graph 74, the steering sensation felt by the driver can be more accurately specified.

  Therefore, the uncomfortable feeling of the steering feeling felt by the driver can be further reduced, and the steering feeling of the steering 1 (FIG. 1) can be further improved. The other effects are the same as those of the first embodiment, and thus the description thereof is omitted.

  Next, third and fourth embodiments will be described. A third embodiment to be described later is a modification of the ECU 10 (first embodiment) shown in FIG. 2, and a fourth embodiment is a modification of the ECU 10 (second embodiment) shown in FIG.

  Moreover, since there is no change regarding the functional block of ECU10 in each of 1st Example, 3rd Example, 2nd Example, and 4th Example, about the functional block of ECU10 which concerns on 3rd, 4th Example, FIG. 2 and FIG. 9 are used respectively.

  In the third embodiment, as in the first embodiment, the convergence feeling calculator 25a (FIG. 2) determines the steering sensation by the classification map 71 ((a) of FIG. 7).

  However, in this embodiment, when a change occurs in the determination result, that is, when the previous determination result is different from the current determination result, the previous determination result is prioritized and the current determination result is not applied. The previous determination result is an example of the first determination result in the present invention, and the current determination result is an example of the second determination result in the present invention.

  Then, only when the determination result similar to the determination result of this time is continuously obtained a predetermined number of times after this time, the determination result obtained by applying the predetermined number of times is applied, and the steering feeling is changed continuously. If the predetermined number of times cannot be obtained, the steering feeling is not changed.

  Specifically, when the determination result based on the classification map 71 ((a) in FIG. 7) is the steering sensation A last time and the steering sensation B this time, the steering sensation that is the previous determination result is given priority, and this time The steering sensation B that is the determination result is not applied.

  Then, when the steering sensation B is obtained a predetermined number of times (for example, 10 times) continuously after this time, the determination result is changed from the steering sensation A to the steering sensation B, and the predetermined number of times (for example, (10 times) If the result is not obtained, the determination result is left as steering feeling A.

  Here, as an example of a case where a determination result similar to the above-described determination result is not continuously obtained a predetermined number of times (for example, 10 times) after this time, first, it is determined that the steering feel is A, and then The steering sensation B is determined. Thereafter, the steering sensation B is determined to be the steering sensation A or the steering sensation C after being determined to be the steering sensation B less than a predetermined number of times (for example, 8 times). Then, after determining in the order of the steering sensation B and the steering sensation C, the determination may be repeatedly performed in the order of the steering sensations A, B, and C.

  Since the determination method as described above is also performed in the convergence gain calculator 25b (FIG. 9) in the fourth embodiment, the description in the convergence gain calculator 25b is omitted.

  Thus, in the third and fourth examples of the present embodiment, each ECU 10 has the same determination result (steering feeling) in addition to the above-described steering feeling determination methods (first to fourth examples). ) Is successively verified whether or not the predetermined number of times has been obtained. As a result of the verification, if the determination result is continuously obtained a predetermined number of times, the steering feeling is changed by applying the determination result, and if the determination result is not continuously obtained a predetermined number of times, The determination result is not applied, and the steering feeling is not changed. For this reason, even when a determination result changes frequently, it can suppress that a steering feeling is frequently changed based on the said determination result.

  Thereby, the uncomfortable feeling of the steering feeling felt by the driver can be further reduced, so that the steering feeling of the steering 1 (FIG. 1) can be improved. Since other effects are the same as those in the first and second embodiments, description thereof will be omitted.

  Finally, a fifth embodiment shown in FIG. 12 and a sixth embodiment shown in FIG. 13 will be described.

  An ECU 10 (fifth embodiment) shown in FIG. 12 is another modification of the ECU 10 (first embodiment) shown in FIG. 2, and a filter 71 is further provided between the convergence gain calculator 25a and the multiplier 32. Is provided.

  Similarly, the ECU 10 (sixth embodiment) shown in FIG. 13 is another modification of the ECU 10 (second embodiment) shown in FIG. 9, and is further provided between the convergence gain calculator 25 b and the multiplier 32. A filter 71 is provided.

  Here, the above-described filter 71 is composed of, for example, an LPF (Low Pass Filter). In each embodiment (first and second embodiments), the gain G output from the convergence gain calculator (25a, 25b) is input to the multiplier 32 via the filter 71. The filter 71 is an embodiment of the filter means in the present invention.

  As described above, in the fifth and sixth examples of the present embodiment, each ECU 10 adds a certain steering feeling (for example, in addition to the above-described steering feeling determination methods (first and second examples)). When the steering sensation A) is changed to another steering sensation (for example, the steering sensation B), the gain G output from each of the convergence gain calculators 25a and 25b corresponding to the change is passed through the filter 71. , Input to the multiplier 32. For this reason, an abrupt change in the gain G based on the change in the steering feeling can be suppressed by the action of the filter 71 that smoothes the change in the gain.

Thus, since it is possible to suppress an abrupt change of the drive current command value I _d outputted to the motor driver 51 (FIG. 8), when switching the steering sense, a steering hand discomfort in the steering feeling You can avoid feeling. Since other effects are the same as those in the first and second embodiments, description thereof will be omitted.

  In the present invention, various embodiments other than those described above can be adopted. For example, in all examples (first to sixth examples) of the above embodiment, the differential gain calculator 22 (for example, FIG. 2) stores in advance three different types of differential gain curves (FIG. 3) depending on the vehicle speed V. However, the present invention is not limited to this, and the vehicle speed V may be set more finely, and more types of differential gain curves for each vehicle speed V may be stored.

In all examples of the above embodiment, the differential gain g when the vehicle speed V is V ₀ in the differential gain curve (FIG. 3) is set to a constant value regardless of the value of the steering torque T, and the vehicle speed V is The differential gain g in the case of V ₁ is set to a value that decreases as the value of the steering torque T increases. Similarly, the differential gain g in the case where the vehicle speed V is V ₂ is increased in the value of the steering torque T. However, the present invention is not limited to this, and may be a differential gain g that is constant regardless of the value of the steering torque T at different vehicle speeds V (V ₀ , V ₁ , V ₂ ). Further, the differential gain g when the vehicle speed V is V0 may be a value that decreases as the value of the steering torque T increases. Further, there may be a value (region) of the steering torque T such that the differential gain g when the vehicle speed V is V1 or V2 is larger than the differential gain g when the vehicle speed V is V0.

  In all the examples of the above embodiment, the first current command value calculator 23 (for example, FIG. 2) stores in advance three types of first current command value curves (FIG. 4) that differ depending on the vehicle speed V. However, the present invention is not limited to this, and the vehicle speed V may be set more finely and more types of first current command value curves for each vehicle speed V may be stored.

Further, in all examples of the above embodiment, the steering torque T is set to a positive value regardless of the rotation direction of the steering 1, and the first current is calculated from the value of the steering torque T and the first current command value curve for each vehicle speed V. Although the command value I ₁ is calculated (FIG. 4), the present invention is not limited to this, and the steering torque T when the rotation direction of the steering 1 is the right direction is a positive value, and the steering torque T when the rotation direction is the left direction is negative. As a value, the first current command value I ₁ may be calculated from the value of the steering torque T and the first current command value curve for each vehicle speed V.

In this case, the magnitude relationship between the predetermined values T ₀ , T ₁ , T ₂ when the rotation direction of the steering wheel 1 is the left direction is T ₀ ≧ T ₁ ≧ T ₂ , and T ₀ <0. The first current command value curve is a curve in which the curve shown in FIG. 4 and a curve (not shown) obtained by rotating the curve 180 degrees around the origin (a point where T = 0 and I ₁ = 0) are continuous. (not shown). Therefore, when the steering torque T is a negative value, the first current command value I ₁ is a negative value.

Further, in all examples of the above embodiment, the steering torque T at which the first current command value I ₁ is saturated in the first current command value curve (FIG. 4) for each vehicle speed V is set to the predetermined values T ₀ , T ₁ and T _2, and the relationship between these predetermined values T ₀ , T ₁ and T ₂ is T ₀ ≦ T ₁ ≦ T _2. However, the present invention is not limited to this, and T ₂ ≦ T ₀ ≦ T ₁ may be used. That is, for the magnitude relationship of the predetermined value _{T 0, T 1, T 2} , may not be formed in particular restrictions.

In all examples of the above-described embodiment, in the first current command value curve for every vehicle speed V (Fig. 4), the saturation value of the first current command value I ₁ is, although different for each vehicle speed V, the limited thereto The value may not be different for each vehicle speed. In other words, the predetermined value T _0, the first current command value in the T ₁ I ₁ is may also be the same, as a predetermined value T _0, the first current command value in the T ₂ I ₁ are the same Also good. Similarly, to the first current command value _{I 1} at the predetermined value _T 1, _{T 2} may be set to be equal, predetermined value _{T 0,} T 1, the first current command value in the _{T 2 I 1} is the same It may be made to become.

  In all examples of the above embodiment, the classification map 71 (FIG. 7A) is a classification map in which four types of steering sensations A to D are distributed. However, the present invention is not limited to this. Furthermore, a classification map in which a variety of steering sensations are distributed may be used.

  In this case, each convergence gain calculator 25a, 25b has a correspondence table 72 in which the ID and gain value (gain G) related to the determination result in the classification map 71 are associated (FIG. 7B). ) Is also stored in advance, and as the type of steering sensation in the classification map 71 increases, the ID related to the determination result (steering sensation) in the classification map 71 also needs to be increased. It is also necessary to set a gain value (gain G).

  Further, in all examples of the above embodiment, in the case of determining the steering sensation of the portion where the steering sensation A and the steering sensation B overlap in the classification map 71 ((a) of FIG. 7), the steering sensation is obtained. When B is preferentially applied as a determination result and the steering sensation where the steering sensation B and the steering sensation C overlap is determined (gray portion), the steering sensation B is preferentially applied as a determination result. For example, when determining the steering sensation of a portion (shaded portion) where the steering sensation A and the steering sensation B overlap, the steering sensation A may be preferentially applied as a determination result. That is, the priority order of the steering senses can be arbitrarily selected in the overlapping portions of the steering senses.

  In the second, fourth, and sixth examples of the above embodiment, a specific (important) steering sensation in the discrimination graph 74 (FIG. 10) stored in advance in the convergence gain calculator 25b is defined as the steering sensation A. However, the present invention is not limited to this, and the steering sensation B or the steering sensation C may be a specific steering sensation.

In the second, fourth, and sixth examples of the above embodiment, threshold values α and β for the steering torque T and threshold values γ and δ for the differential command value T ₁ are set in the discrimination graph 74 (FIG. 10). When the steering torque T is a value between the threshold value α and the threshold value β and the differential command value T ₁ is a value between the threshold value γ and the threshold value δ, a predetermined steering feeling ( For example, it is determined that it corresponds to the steering sensation A), but is not limited thereto. For example, the steering torque T is a value between the threshold α and the threshold β, and the differential command value T ₁ is the threshold γ and the threshold. If it is not a value between δ, it may be determined that a specific steering feeling (for example, steering feeling A) is met.

In addition to this, as a condition corresponding to a specific steering sense, for example, the steering torque T is not a value between the threshold value α and the threshold value β, and the differential command value T ₁ is a threshold value γ and a threshold value δ. The steering torque T may not be a value between the threshold value α and the threshold value β, and the differentiation command value T ₁ may not be a value between the threshold value γ and the threshold value δ. .

  In all the examples of the above embodiment, the angular velocity (rotational operation speed) is obtained using the angular velocity sensor 12, but the present invention is not limited to this, and a sensor (not shown) for detecting the amount of rotation of the steering 1 or the motor 15 The angular speed may be estimated from the output value of the motor rotation sensor 14 or the like that detects the rotational speed of the motor.

  In all examples of the above embodiment, the motor 15 is a brush motor. However, the present invention is not limited to this, and a brushless motor may be used.

  Furthermore, in the above-described embodiment, the electric power steering system 100 is mounted on a vehicle (for example, an automobile). However, the present invention is not limited to this. May be.

It is a figure showing an electric power steering system. It is a figure which shows the functional block of ECU. It is a figure which shows a differential gain curve. It is a figure which shows a 1st electric current command value curve. It is a figure which shows a 1st viscosity value curve. It is a figure which shows a 2nd viscosity value curve. It is a figure which shows a classification map and a correspondence table. It is a figure which shows a motor drive part. It is a figure which shows the other Example of the functional block of ECU. It is a figure which shows a discrimination graph. It is a figure which shows the table | surface for performing final determination. It is a figure which shows the other Example of the functional block of ECU. It is a figure which shows the other Example of the functional block of ECU.

Explanation of symbols

1 Steering (steering mechanism)
10 ECU
DESCRIPTION OF SYMBOLS 11 Torque sensor 12 Angular velocity sensor 13 Vehicle speed sensor 14 Motor rotation sensor 15 Motor 21 Differential command value calculator 22 Differential gain calculator 23 First current command value calculator 24 Convergence value calculator 25a, 25b Convergence gain calculator 31, 32 Multiplication Device 33 Adder 34 Subtractor 51 Motor drive unit 71 Classification map 72 Correspondence table 74 Specific sense discrimination graph

Claims (6)

Steering torque input means for inputting a steering torque of a steering mechanism of the vehicle;
Angular velocity input means for inputting the rotational angular velocity of the steering mechanism;
Vehicle speed input means for inputting the vehicle speed of the vehicle;
A rotational speed input means for inputting a rotational speed of a motor that gives an auxiliary force to the steering mechanism;
A drive current command value output means for outputting a drive current command value for driving the motor based on inputs from the steering torque input means, the angular speed input means, the vehicle speed input means, and the rotational speed input means; ,
In the electric power steering control device with
The drive current command value output means includes
Differential command value calculating means for differentiating the steering torque to calculate a differential command value;
Differential gain calculating means for calculating a differential gain that is a gain for the differential command value based on the steering torque and the vehicle speed;
First current command value calculating means for calculating a first current command value based on the steering torque and the vehicle speed;
A convergence value calculating means for calculating a convergence value based on the vehicle speed and the rotational speed;
A convergence gain calculating means for determining a steering feeling of the steering mechanism based on the steering torque and the rotational angular velocity, and calculating a convergence gain that is a gain for the convergence value based on the determination result;
Second current command value calculating means for calculating a second current command value by multiplying the differential command value and the differential gain;
A convergence command value calculating means for calculating a convergence command value by multiplying the convergence value by the convergence gain;
A third current command value calculating means for calculating a third current command value by adding the first current command value and the second current command value;
Drive current command value calculating means for calculating the drive current command value by subtracting the convergence command value from the third current command value;
An electric power steering control device comprising: In the electric power steering control device according to claim 1,
The convergence gain calculating means includes first determination means for determining a steering feeling corresponding to each steering torque and rotational angular velocity from among a plurality of steering feelings classified based on the steering torque and the rotational angular velocity; An electric power steering control device comprising: a convergence gain determining unit that determines the convergence gain corresponding to the determination result based on a determination result by the first determination unit. In the electric power steering control device according to claim 2,
When there are a plurality of steering sensations corresponding to the steering torque and the rotational angular velocity, the first determination means determines one of the plurality of steering sensations as a determination result according to a predetermined priority order. An electric power steering control device. In the electric power steering control device according to claim 3,
The convergence gain calculating means includes second determination means for determining whether the steering sensation of the steering mechanism corresponds to a specific steering sensation based on the steering torque, the differential command value, and the vehicle speed. And
When the determination result by the second determination unit is applicable, it is verified whether or not there are a plurality of steering sensations determined by the first determination unit, and when there are a plurality of steering sensations, the second determination unit It is verified whether or not the specific steering sensation according to the above coincides with any of the plurality of steering sensations by the first determination means. An electric power steering control device characterized by determining as a steering sensation. In the electric power steering control device according to any one of claims 2 to 4,
The current gain calculating means includes
When the first determination result that is the determination result of the first determination means and the second determination result that is the determination result subsequent to the first determination result are not different, the steering mechanism is based on the second determination result. The steering sensation of
When the first determination result is different from the second determination result, and the same determination result as the second determination result is not continuously obtained a predetermined number of times after the second determination result, Determining a steering sensation of the steering mechanism based on the first determination result;
When the first determination result is different from the second determination result, and the same determination result as the second determination result is continuously obtained a predetermined number of times after the second determination result, An electric power steering control device that determines a steering feeling of the steering mechanism based on a second determination result. In the electric power steering control device according to any one of claims 1 to 5,
Electric power steering control characterized in that filter means for smoothing a change in the convergence gain output from the convergence gain calculation means is provided between the convergence gain calculation means and the convergence command value calculation means. apparatus.

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