JPH0695743A - Motor positioning controller - Google Patents

Abstract

PURPOSE:To provide the motor positioning controller where the responsiveness and the stability of a control system are compatible with each other. CONSTITUTION:In a brake controller as the motor positioning controller, a deviation calculating circuit 90 obtains the deviation between the target crank angle obtained by a control target crank angle determining circuit 74 and the crank angle obtained by a crank angle calculating circuit 78; and if the deviation is smaller than a prescribed value, a differential stop signal is led out from a first discriminating circuit 96 to a differentiating circuit 92 to make a differential term zero. Thus, the instability of control caused by the occurrence of a large differential term due to a small disturbance in the vicinity of the target crank angle is prevented regardless of motor control of high responsiveness.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor positioning control device for controlling the rotational position of a motor based on the result of calculation after performing proportional, differential and integral calculation processing. The present invention relates to a motor positioning control device that changes a differential term that is set based on a deviation between a control value after being actually controlled and a control target value based on the deviation.

[0002]

2. Description of the Related Art Conventionally, when performing servo control, based on a deviation between a control target value and an actually controlled value for the purpose of improving responsiveness and preventing overshooting,
Proportional / differential / integral control (hereinafter referred to as PID control) is performed. For example, when the position of the actuator is controlled by driving the motor, it is possible to quickly control the actuator to the target position by the PID control and prevent overshooting to converge the target position.

However, even if the deviation is small (the control value converges near the target control value), the differential term may cause vibration in a control system with a fast change speed (response).

Therefore, in a system with a fast response, the value of the differential term is set to be proportional to the deviation to prevent the control value from oscillating (Japanese Utility Model Publication No. 2-72492).

[0005]

Even in the PID control in which the above measures are taken, when controlling a system with a quick response, even if the above measures are taken, a large differential term is generated due to a small disturbance. There is a risk that the value of will occur and the control system will become unstable.

The present invention has been made in order to solve this kind of problem, and an object of the present invention is to provide a motor positioning control device that achieves both high responsiveness and stability of the control system.

[0007]

In order to achieve the above-mentioned object, the present invention calculates the deviation between the position detecting means for detecting the rotational position of the motor and the target position of the motor and the current rotational position, Deviation output means for outputting as a deviation signal, judgment means for judging whether or not the deviation signal is within a predetermined range, and if the deviation signal is judged to be outside the predetermined range by the judgment means, A control signal that is a combination of a proportional proportional signal, a differential signal obtained by differentiating the deviation signal, and an integrated signal obtained by integrating the deviation signal is output, and if the deviation signal is determined to be within a predetermined range, The present invention is characterized by including a proportional signal proportional to the deviation signal and a control means for outputting a control signal obtained by combining an integrated signal obtained by integrating the signal, and driving the motor by the control signal.

[0008]

In the motor positioning control device according to the present invention, when the PID control is performed, it is determined whether the deviation signal detected by the deviation detecting means is within a predetermined range,
When it is determined that the value is out of the predetermined range, a high responsiveness is obtained because a control signal that is a combination of a proportional signal, a derivative signal, and an integral signal based on the deviation signal is output, that is, PID control is performed. Have. When it is determined that the deviation signal is within the predetermined range, the control means outputs a control signal that combines only the proportional signal and the integral signal. Therefore, even if the system has a fast response, there is a small disturbance near the control target value. A large differential signal is output to, and the control value does not vibrate. Therefore, it is possible to perform stable motor positioning control with high responsiveness.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A control method according to the present invention will be described in detail below with reference to the accompanying drawings with reference to preferred embodiments.

First, a brake control device according to this embodiment to which a motor positioning control device is applied will be described.

FIG. 1 is a schematic configuration diagram of a brake control device 10 according to the present embodiment, in which a control unit 12 controls a modulator 14 to control a brake pressure to obtain an optimum braking force.

The control unit 12 detects wheel speeds via wheel speed sensors 16 and 16a provided near driven wheels (front wheels) Wf and drive wheels (rear wheels) Wr, and outputs pulse signals of the wheel speeds. It is installed in the control unit 12.

The brake device 18 includes a master cylinder 24 driven by a brake lever 22 provided on a handle 20 and a caliper cylinder 2 for braking a front wheel Wf.
6, the master cylinder 24 and the caliper cylinder 26
Are mutually connected via a modulator 14.
The master cylinder 24 adjusts the hydraulic pressure under the action of the brake lever 22 and transmits the hydraulic pressure to a cut valve described later, while the caliper cylinder 26 controls the disc plate based on the hydraulic pressure controlled by the cut valve. The braking force is applied to 28.

The modulator 14 of the front wheels Wf is provided with a motor controller 32 for energizing and deenergizing the DC motor 30 which constitutes the modulator to drive and control the DC motor 30. The motor controller 32 is electrically connected to the control unit 12 and receives the signal derived from the control unit 12. A pinion 34 is connected to the drive shaft of the DC motor 30, and a gear 36 meshes with the pinion 34. A crankshaft 38 is fixed to the center of the gear 36,
One end of a crank pin 42 is connected to the crank shaft 38 via a crank arm 40. This crank pin 4
A crank arm 44 is connected to the other end portion of 2, and a potentiometer 46 that detects the deviation angle of the crank pin 42 is connected to the crank arm 44.

A cam bearing 48 is rotatably mounted on the outer circumference of the crank pin 42.
8 is pressed upward via the return spring 50. The expander piston 52 that moves up and down due to the displacement of the cam bearing 48 contacts the upper surface of the cam bearing 48, and the cut valve 54 is opened and closed under the action of the vertical movement of the expander piston 52. It The cut valve 54 is vertically displaceable in the cut valve storage portion 56, and an input port 58 communicating with the master cylinder 24 is provided on the upper surface of the cut valve 54, while the cut valve storage portion 56 and the extract valve 54 are connected to each other. An output port 60, which communicates with the caliper cylinder 26, is provided at the connecting portion of the panda piston 52. The input port 58 and the output port 60 communicate with each other through a communication hole 62 defined on the outer peripheral surface of the cut valve 54.

The brake control device 1 having such a configuration
0, the control configuration of the control unit 12 and the controller 32 related to the control method of the present invention will be described with reference to a block diagram (FIG. 2).

The control unit 12 has a front wheel W.
A wheel speed calculation circuit 64 that calculates the wheel speed from the output values of the wheel speed sensor 16 of f and the wheel speed sensor 16a of the rear wheel Wr, and a vehicle speed calculation circuit 66 that calculates and estimates the traveling speed of the vehicle from the rotation speed of the wheels. And a slip ratio calculation circuit 68 for obtaining the slip ratio of the wheel based on the traveling speed of the vehicle body and the rotation speed of the wheel, and a wheel acceleration / deceleration calculation circuit 70 for calculating the acceleration / deceleration of the front wheel Wf and the rear wheel Wr from the wheel speed. And a caliper pressure increase / decrease amount determination circuit 72 for determining the increase / decrease amount of the caliper pressure applied to the caliper cylinder 26 from the slip ratio and the wheel acceleration / deceleration, and the crankpin of the modulator 14 based on the increase / decrease amount of the caliper pressure. And a control target crank angle determination circuit 74 for obtaining a target crank angle which is a control target in which the position of 42 is raised or lowered. That.

The motor controller 32 includes an A / D conversion circuit 76 for converting the output of the potentiometer 46 for detecting the position information of the crank pin 42 of the modulator 14 into a digital value, and a crank angle for obtaining a crank angle based on the digital value. An arithmetic circuit 78, a PID determining circuit 80 for obtaining a PID value based on the deviation between the crank angle and the target crank angle, and a duty ratio determining circuit 81 for determining a pulse duty ratio based on the PID value.
A PWM circuit 82 that generates a pulse train based on the duty ratio determined by the duty ratio determination circuit 81, and a motor driver 84 that drives the DC motor 30 according to the pulse train.

As shown in FIG. 3, the PID determining circuit 80 calculates a deviation from the crank angle output from the crank angle calculating circuit 78 and the target crank angle output from the control target crank angle determining circuit 74. Arithmetic circuit 90
And a proportional circuit 9 for deriving a proportional signal based on the deviation.
1, a differentiating circuit 92 for deriving a differential signal based on the deviation, an integrating circuit 94 for deriving an integral signal based on the deviation, and a differentiating operation stop signal to the differentiating circuit 92 based on the deviation. The first determination circuit 96 and the PWM
A second determination circuit 98 that derives a stop signal of the integration operation based on the signal derived from the circuit 82, and a PID calculation circuit 10 that obtains a PID value from the deviation, the differential signal, and the integrated signal.
With 0 and.

On the other hand, the modulator 14a of the rear wheel Wr is
The master cylinder 24a connected to the brake pedal 23 of the rear wheel Wr and the caliper cylinder 26a connected to the disc plate 28a of the rear wheel Wr are communicated with each other.
It has the same configuration as the modulator 14 described above, and detailed description thereof will be omitted.

Next, a control method in the brake control device 10 thus configured will be described.

First, the wheel speeds of the front wheels Wf and the rear wheels Wr are calculated based on the input signals from the wheel speed sensors 16 and 16a, and the slip ratios of the front wheels Wf and the rear wheels Wr with respect to the road surface are calculated from the wheel speeds. Based on this, it is determined whether or not to enter the antilock control that limits the brake pressure.

When anti-lock control is not performed (normal control), the crank pin 42 is held at a preset upper limit position by the elastic force of the return spring 50, and the cam bearing 48 mounted on the crank pin 42 is It is maintained in a state of being pushed up by the expander piston 52. As a result, the cut valve 54 is pushed up by the expander piston 52, and the input port 58 and the output port 60 communicate with each other.

Then, the master cylinder 24 is urged by gripping the brake lever 22, and the brake pressure generated by the master cylinder 24 is transmitted to the caliper cylinder 26 via the input port 58 and the output port 60. The braking force is applied to the disc plate 28.

On the other hand, when it is determined that the antilock control is to be entered based on the slip ratio, the control is performed as shown in the flowchart of FIG.

First, from the wheel acceleration / deceleration calculated on the basis of the slip ratio and the wheel speed, for example, an increase / decrease amount of the brake pressure, that is, a displacement amount of the crank pin 42 based on a table such as a pressure increase / decrease map not shown. (Target crank angle θT) is set. On the other hand, the motor controller 32 outputs the output signal from the potentiometer 46 to the A / D.
The conversion circuit 76 performs analog / digital signal conversion, and the crank angle calculation circuit 78 calculates the present crank angle θC based on the output signal (step S).
1).

The PID determination circuit 80 determines the PID value as follows based on the crank angle θC and the target crank angle θT thus obtained.

First, the deviation calculation circuit 90 calculates the difference between the target crank angle θT and the crank angle θC as the deviation Δθ (step S2).

Further, the first judgment circuit 96 judges whether or not the absolute value of the deviation Δθ is equal to or larger than the predetermined value θDH (the deviation Δθ is outside the predetermined range) (step S3).

If the deviation Δθ is within the predetermined range, the differentiation stop signal is derived to the differentiation circuit 92 and the differentiation term Dθ is set to 0 (step S4). That is, if the deviation Δθ is within the predetermined range, it is considered that the positioning of the crank pin 42 is completed, and the differential operation is stopped. Therefore, even when controlling a motor with high responsiveness, generation of a large differential term Dθ due to small disturbance is prevented. The deviation Δθ
Is out of the predetermined range, the differentiating circuit 92 multiplies the difference between the deviation Δθ calculated in the current sampling and the deviation ΔθP calculated in the previous sampling by the differential gain KD to obtain the differential term Dθ (step S5). ).

Then, in the second judgment circuit 98, PM
It is determined whether the PWM signal value, which is derived from the W circuit 82 and is the control signal for the DC motor 30, is equal to or greater than the integral range PWMH corresponding to a duty ratio of 80% (step S
6) (see FIG. 5). If the PWM signal value is equal to or higher than PWMH, the integration stop signal is derived to the integration circuit 94, and the integration value Iθ
P is set to 0 (step S7). On the other hand, if the PWM signal value is equal to or lower than PWMH, the integration circuit 94 sets the sum of the previous integrated value IθP and the deviation Δθ as the current integrated value IθP (step S8). The integral value IθP is multiplied by the integral gain KI to obtain the integral term Iθ (step S
9). With this integration operation, as shown in FIG. 5, a PID value (PIDa, PIDa corresponding to a duty ratio of 80% (PWMH),
Part A defined by PIDb) (PIDb ≦ PID
Within the range of ≦ PIDa), the output of the motor is displaced according to the change of the PID value. However, outside the range of the section A, the output of the motor causes an overshoot, so that the PID value of the section A is If out of range (PWM ≧ PW
In step S7, the integrated value IθP is set to 0 to prevent overshoot.

Therefore, in the PID arithmetic circuit 100,
The PID value is obtained by adding the obtained deviation Δθ, the differential term Dθ, and the integral term Iθ (step S10). Further, the deviation Δθ is replaced with the previous deviation ΔθP (step S11). In this embodiment, in the proportional circuit 91, the proportional gain is set to 1 and the direct deviation Δθ is used to determine PI.
Although the D value is obtained, it goes without saying that the proportional circuit 91 multiplies the deviation Δθ by a proportional gain to derive a proportional signal and PI
The D value may be obtained.

The PID value is output to the duty ratio determining circuit. Here, whether the PID value is positive or negative is determined (step S12). If the PID value is positive, it is determined whether or not it is equal to or more than the rotation effective value PIDH described later (step S1
3). When the PID value is equal to or greater than the effective rotation value PIDH, the forward rotation (brake pressure increasing direction) flag is set (step S14), and the sum of the PID value multiplied by the coefficient a and the predetermined number b is used as the PWM signal. Ask (Step S
15). The coefficient a and the predetermined number b are the slope and intercept of the portion B in FIG.

When it is determined in step S12 that the PID value is negative, it is determined whether the PID value is equal to or less than the rotation effective value PIDL described later (step S1).
6). When the PID value is equal to or less than the rotation effective value PIDL, a reverse rotation (brake pressure decreasing direction) flag is set (step S17), and the sum of PID multiplied by a coefficient c and a predetermined number d is obtained as a PWM signal (step S17). Step S1
8). The coefficient b and the predetermined number d are C in FIG.
The slope and intercept of the part.

Further, in step S13, the PID value is smaller than the rotation effective value PIDH, or in step S13.
When it is determined in 16 that the PID value is larger than the rotation effective value PIDL, the brake flag is set (step S19) and the PWM signal is set to 0 (step S20).

The rotation effective values PIDH and PIDL are
As shown in FIG. 5, when the PID value is less than this, the duty ratio is a threshold value of 0. That is, when the PID value is small, the influence of noise becomes large, and in order to prevent this, the duty ratio is set to 0 if PIDL <PID <PIDH.

The DC motor 30 is driven by the motor driver 84 based on the PWM signal and the flag thus obtained. For example, when the forward rotation flag and the PWM signal are derived to the motor driver 84, the DC motor 30
Are rotated in the normal rotation (pressure increase) direction, the crank shaft 38 is rotated, and the crank pin 42 is displaced, whereby the expander piston 52 is displaced upward, and the capacity of the output port 60 is reduced, so that the caliper is reduced. Increase pressure. When the brake flag and the PWM signal are derived, the DC motor 30 is stopped and the displacement of the expander piston 52 is stopped.

As described above, in the brake control device of the present embodiment, when the deviation Δθ is equal to or less than the predetermined value θDH when performing the PID control, the differentiation stop signal is derived from the first determination circuit 96 to the differentiation circuit 92, Since the differential term Dθ is set to 0, a large differential term Dθ is generated due to a small disturbance as shown by the broken line D in FIG. 6 even when the motor control has high responsiveness while the crank pin 42 is located near the target crank angle. The control will not become unstable. Further, when the deviation Δθ is equal to or larger than the predetermined value θDH, the normal differential operation is performed, so that the control with good responsiveness is performed. Furthermore, PW is higher than PWMH, which is a duty ratio of 80% corresponding to the motor output value.
If M is large, the integral term Iθ is set to 0, so E in FIG.
It is possible to reliably suppress the overshoot as indicated by the broken line portion, and since the integration operation is performed again when PWM becomes equal to or lower than PWMH, the steady deviation can be eliminated and the target value can be converged.

[0039]

According to the motor positioning control apparatus of the present invention, the following effects can be obtained.

That is, when the PID control is performed, if the deviation is within a predetermined range, the control means outputs a control signal that combines only the proportional signal and the integral signal. The value does not oscillate after being controlled due to disturbance near the value. Further, when the deviation is out of the predetermined range, the normal PID control is performed, so stable and highly responsive motor positioning control can be performed.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a brake control device including a motor positioning control device according to the present invention.

FIG. 2 is a configuration diagram illustrating a motor positioning control device according to the present invention in relation to the brake control device.

FIG. 3 is a PI of a motor positioning control device according to the present invention.
It is a structure explanatory view of a D determination circuit.

FIG. 4 is a PI of a motor positioning control device according to the present invention.
6 is a flowchart showing a D control method.

FIG. 5 is a PI of the motor positioning control device according to the present invention.
It is a figure which shows a D control method.

FIG. 6 is a PI of a motor positioning control device according to the present invention.
It is a figure which shows a D control result.

[Explanation of symbols]

 10 ... Brake control device 12 ... Control unit 14 ... Modulator 16, 16a ... Wheel speed sensor 30 ... DC motor 32 ... Motor controller 42 ... Crank pin 46 ... Potentiometer 74 ... Control target crank angle determination circuit 78 ... Crank angle calculation circuit 80 ... PID determining circuit 81 ... Duty ratio determining circuit 82 ... PWM circuit 90 ... Deviation computing circuit 91 ... Proportional circuit 92 ... Differentiating circuit 94 ... Integrating circuit 96 ... First determining circuit 98 ... Second determining circuit 100 ... PID computing circuit

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[Procedure amendment]

[Submission date] September 30, 1992

[Procedure Amendment 1]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 1

[Correction method] Change

[Correction content]

[Figure 1]

Claims (1)

[Claims] 1. A position detecting means for detecting a rotational position of a motor, and a deviation between a target position of the motor and a current rotational position is calculated,
Deviation output means for outputting as a deviation signal, judgment means for judging whether or not the deviation signal is within a predetermined range, and if the deviation signal is judged to be outside the predetermined range by the judgment means, A proportional signal proportional to
A control signal that is a combination of a differential signal obtained by differentiating the deviation signal and an integrated signal obtained by integrating the deviation signal is output, and when the deviation signal is determined to be within a predetermined range, a proportional proportion to the deviation signal A motor positioning control device comprising: a control unit that outputs a control signal that is a combination of a signal and an integrated signal obtained by integrating the signal, and drives the motor according to the control signal.