JP4331344B2 - Motor control device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to, as an example, a motor control device that controls a braking force applied to a rotationally driven motor.
[0002]
[Prior art]
As an example, a motor used for an automatic door or the like uses a brake signal as a drive signal supplied to the motor from an inverter circuit when braking against rotation and adjusting a braking force. As a brake signal for adjusting the braking force, a signal obtained by subjecting the brake logic signal to pulse width modulation (PWM) with a certain constant high frequency modulation pulse is used.
[0003]
[Problems to be solved by the invention]
In a conventional motor braking system, when the frequency of the modulation pulse is a relatively low frequency band such as a frequency band within a human audible frequency band, the motor is turned on / off in such a frequency band. Therefore, there is a problem in that noise is generated that can be heard by the surrounding people.
[0004]
Further, when the frequency of the modulation pulse is a relatively high frequency band such as a frequency band exceeding the audible frequency band, the frequency of the brake signal supplied to the motor becomes excessively high, and sufficient braking force is applied to the motor. It becomes difficult to give. In particular, if the brake-off time of the PWM modulated brake signal is increased as much as possible, there is a problem that the braking force of the motor is greatly reduced. In either case, the designed braking performance cannot be obtained, and the operational reliability is lowered.
[0005]
When braking with a general braking logic signal power generation braking method, when the rotational speed is high, the amount of power generation is large and the braking is strong, but when the rotational speed becomes low, even if the braking command is the same, it is actually There is a problem when the braking force of the vehicle becomes weaker. As the rotational speed becomes slower, the slope of the speed change due to braking becomes smoother.
[0006]
The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a motor control device with improved operational reliability by braking the motor in a desired manner. is there.
[0007]
[Means for Solving the Problems]
The motor control apparatus of the first aspect of the present invention, in the motor controller a pulse width modulated braking logic signal is used to brake the rotation state of the motor, positive regulation to generate a constant positive regulatory power regardless of age Positively regulated power command control means for generating a power command signal, secondary braking force command control means for generating a secondary braking force command signal for generating a secondary braking force that increases with elapsed time , and the positively regulated power command signal An elapsed time calculating means for calculating an elapsed time from the occurrence of the occurrence, and when the elapsed time calculated by the elapsed time calculating means exceeds a predetermined reference elapsed time, a secondary that is larger than the positive regulation power command signal Braking force command switching control means for selecting a braking force command signal .
[0008]
The motor control apparatus of the invention of claim 2, wherein, in the motor controller a pulse width modulated braking logic signal is used to brake the rotation state of the motor, positive regulation to generate a constant positive regulatory power regardless of the rotational speed A positive regulation power command control means for generating a power command signal; a secondary braking force command control means for generating a secondary braking force command signal for generating a secondary braking force that gradually increases as the rotational speed decreases; a rotational speed calculating means for calculating a rotational speed of the motor after the occurrence of the power command signal, when the rotation speed calculated in the rotational speed calculating means, falls below the reference rotational speed predetermined, positive regulation power command Braking force command switching control means for selecting a secondary braking force command signal larger than the signal .
[0009]
[Action]
In the motor control device according to the first aspect of the present invention, a pulse width modulated braking logic signal for braking the rotation state of the motor is used. When braking the motor, first, a positive regulation power command signal is output from the positive regulation power command control means, and a constant positive regulation power is generated in the motor regardless of the elapsed time . On the other hand, a secondary braking force command signal that increases with elapsed time is output from the secondary braking force command control means. When the elapsed time calculating means calculates the elapsed time from the generation of the regular regulation power command signal and the elapsed time calculated by the elapsed time calculating means exceeds a predetermined reference elapsed time, the braking force command switching control means Selects a secondary braking force command signal that is larger than the positively regulated power command signal .
[0010]
Thereby, even if the frequency of the modulation signal used for the pulse width modulation is high or relatively low, the secondary braking force brakes the motor following the initial positive regulation power. The braking performance can be realized, and the operational reliability is improved.
[0011]
In the motor control device according to the second aspect of the present invention, a pulse width modulated braking logic signal for braking the rotation state of the motor is used. When braking the motor, first, a positively regulated power command signal is output from the positively regulated power command control means, and a constant positively regulated power is generated in the motor regardless of the rotational speed . On the other hand, the secondary braking force command control means outputs a secondary braking force command signal that gradually increases as the rotational speed decreases. When the rotation speed calculation means calculates the rotation speed of the motor after the generation of the regular regulation power command signal, and the rotation speed of the motor calculated by the rotation speed calculation means falls below a predetermined reference rotation speed, the braking force command switching control means selects the larger secondary braking force command signal than the normal braking force command signal.
[0012]
Thereby, the same effect as the effect demonstrated regarding Claim 1 is realizable.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a block diagram showing an electrical configuration of a motor control device (hereinafter referred to as a control device) 1 according to a first embodiment of the present invention, and FIG. 2 shows an electrical configuration of a motor drive control unit of the control device 1. FIG. 3 is a waveform diagram showing an example of the operation of the control device 1.
[0014]
Hereinafter, the control device 1 will be described with reference to FIGS. The control device 1 controls the rotation state of the motor 2, in this embodiment, the braking state. The motor 2 is provided with a magnetic pole detection element 3 such as a hole element as an example. A change in the magnetic flux density of the second rotating magnetic field is detected. Thus, the magnetic pole detection element 3 can detect the rotational speed and rotational direction of the motor 2 and the position in the rotational direction, and outputs a position signal SP corresponding thereto. The control device 1 includes a motor drive control unit (hereinafter referred to as a drive control unit) 4 that supplies drive signals Su, Sv, and Sw for driving the motor 2 to rotate.
[0015]
The control device 1 includes, as an example, an input / output command signal control unit (hereinafter referred to as a control unit) 5 formed of a microcomputer or the like, and the control unit 5 performs normal regulation power command control based on an external braking force command S1. The regular regulation power command control unit 6 as a means is caused to output a regular regulation power command. The normal regulation power command signal is a signal for causing the motor 1 to generate a certain level of braking force as shown in FIG.
[0016]
On the other hand, the control unit 5 outputs a braking start command S3 to the elapsed time calculation unit 7 which is an elapsed time calculation means at a timing at which the regular regulation power command control unit 6 generates the regular regulation power. The elapsed time calculation unit 7 calculates the elapsed time T from the time when the braking start command S3 is input. When the elapsed time T exceeds a predetermined reference elapsed time T0, the secondary braking force command control means is a secondary braking force command control means. An output command signal is output to the command calculation unit 8. The secondary braking force command calculation unit 8 outputs the secondary braking force command to the braking force command switching control unit 9. The secondary braking force command is a signal for increasing the braking force with time as shown in FIG.
[0017]
The braking force command switching control unit 9 selects and outputs a high level braking force signal out of the regular regulated power command signal and the secondary braking force command signal. The selected braking force command from the braking force command switching control unit 9 is input to the drive control unit 4, and the drive signals Su, Sv, Sw are output from the drive control unit 4. The drive signals Su, Sv, Sw become the brake signals when the motor 1 is braked.
[0018]
For example, the drive control unit 4 may have an electrical configuration shown in FIG. The drive control unit 4 includes a waveform synthesis circuit 10 to which the position signal SP from the magnetic pole detection element 3 is input. The position signal SP from the magnetic pole detection element 3 is input to the waveform synthesis circuit 10, and the waveform of the position signal SP for each phase is synthesized to output a position velocity direction signal. This makes it possible to determine the phase and period of the position signal SP for each phase, the mutual phase difference and the traveling direction of the phase, that is, the rotational position, rotational speed and rotational direction of the motor 2. A position speed direction signal from the waveform synthesis circuit 10 is input to the speed control circuit 12 and the control unit 5.
[0019]
A speed command signal corresponding to the reference speed is separately input to the control unit 5, and a control signal based on the speed command signal is input to the logic circuit 12 together with a signal from the speed control circuit 11. A control signal for turning on / off each of the 13 transistors is created and output to the inverter circuit 13. A DC power supply is connected to the inverter circuit 13, and voltage / current from the DC power supply is modulated by the inverter circuit 13 and supplied to the motor 2. The level of the drive current supplied to the motor 2 is input from the inverter circuit 13 to the speed control circuit 11 as a feedback signal. In this way, the motor 2 is controlled to rotate at the reference speed based on the speed command signal.
[0020]
In the control device 1 of the present embodiment, when the motor 2 is braked, the control unit 5 is based on a braking force command S1 from the outside to the control unit 5, and the control power command control unit 6 and the elapsed time calculation unit. 7 outputs a braking start signal S3. As a result, a positive restriction power command signal is first output from the positive restriction power command control unit 6. At this time, since the elapsed time T being calculated in the elapsed time calculation unit 7 has not reached the reference elapsed time T0, the secondary braking force command calculation unit 8 corresponds to a secondary braking force of 0 level. A signal is input to the braking force command switching control unit 9, and the braking force command switching control unit 9 outputs a positive regulation power signal from the regular regulation power command control unit 6 to the motor drive control unit 4. As a result, the motor drive control unit 4 gives the motor 2 positive regulation power at a certain level in time as shown in FIG.
[0021]
The elapsed time calculation unit 7 calculates an elapsed time T from the generation of the regular regulation power command signal S3, and when the calculated elapsed time T exceeds a predetermined reference elapsed time T0, a braking force command switching control unit 9 selects a secondary braking force command signal at a level higher than the normal regulation power command signal as shown in FIG. 3 (3), and outputs it to the motor drive control unit 4. As a result, the motor drive control unit 4 gives the motor 2 a secondary braking force at a level that increases with time as shown in the period after the reference elapsed time T0 in FIG.
[0022]
As a result, whether the frequency of the modulation signal used for pulse width modulation is high or relatively low, the secondary braking force that realizes a higher braking force following the initial positive regulation power is applied to the motor. Since 2 is braked, desired braking performance can be realized and operational reliability is improved.
[0023]
FIG. 4 is a block diagram showing the electrical configuration of the control device 1a according to the second embodiment of the present invention, and FIG. 5 is a waveform diagram for explaining the operation of the control device 1a. Hereinafter, the control device 1a will be described with reference to FIGS. The configuration of the control device 1a is similar to the configuration of the control device 1 of the first embodiment, and corresponding parts are denoted by the same reference numerals.
[0024]
A structural feature of the control device 1a is that in the control device 1, instead of the elapsed time calculation unit 7, a rotation speed calculation that calculates the rotation speed of the motor 2 based on the position signal PS from the magnetic pole detection element 3 is used. This is the provision of a rotation speed calculation unit 14 as means. The rotation speed calculation unit 14 calculates the rotation speed R of the motor 2 based on the position signal PS from the magnetic pole detection element 3, and compares the calculated rotation speed R with a predetermined reference rotation speed R0. When the rotational speed R falls below the reference rotational speed R0, a control signal is output to the secondary braking force command calculation unit 8, and the secondary braking force command control unit 8 serving as the secondary braking force command control means A secondary braking force command that gradually increases the braking force as the rotational speed of the motor 2 decreases as shown in 5 (2) is output.
[0025]
The secondary braking force command is input to the braking force command switching control unit 9 as in the case of the control device 1. In the braking force command switching control unit 9, from the regular regulation power command control unit 6 that outputs a regular regulation power command that realizes a constant level of braking force regardless of the rotational speed of the motor 2 as shown in FIG. As described later, the positively regulated power command and the secondary braking force command are switched to each other and output to the motor drive control unit 4a.
[0026]
Since the control device 1a has such a configuration, the motor drive control unit 4a is compared with the motor drive control unit 4 in the case of the control device 1 of the first embodiment, and the logic circuit 12 in the motor drive control unit 4. And an inverter 13. The functions of the remaining waveform synthesis circuit 10 and the speed control circuit 11 are realized by the rotation speed calculation unit 114 in FIG.
[0027]
In the control device 1a of the present embodiment, when the motor 2 is braked, the control unit 5 controls the control unit 5 based on the external braking force command S1 to the control unit 5 and the secondary regulation power command control unit 6 and the secondary braking force. A braking start signal S3 is output to the command calculation unit 8. As a result, a positive restriction power command signal is first output from the positive restriction power command control unit 6. At this time, in the rotation speed calculation unit 14, the calculated rotation speed R does not reach the reference rotation speed R0, so that the secondary braking force command calculation unit 8 corresponds to the secondary braking force of 0 level. A signal is input to the braking force command switching control unit 9, and the braking force command switching control unit 9 outputs a positive regulation power signal from the regular regulation power command control unit 6 to the motor drive control unit 4. As a result, the motor drive control unit 4 gives the motor 2 positive regulation power at a certain level in time as shown in FIG.
[0028]
When the rotation speed R of the motor 2 calculated by the rotation speed calculation unit 14 is lower than a predetermined reference rotation speed R0, the braking force command switching control unit 9 has a secondary level that is higher than the normal regulation power command signal. A braking force command signal is selected as shown in FIG. 5 (3), and is output to the motor drive control unit 4. As a result, the motor drive control unit 4 gives the motor 2 a secondary braking force at a gradually increasing level as shown in the rotational speed range below the reference rotational speed R0 in FIG.
[0029]
Thereby, even in the case of the present embodiment, it is possible to realize the same operational effects as those in the case of the first embodiment.
[0030]
The present invention is not limited to the above-described embodiments, and has a wide variety of modifications without departing from the spirit of the present invention.
[0031]
【The invention's effect】
As described above, in the motor control device according to the first aspect of the present invention, the pulse width-modulated braking logic signal for braking the rotation state of the motor is used. When braking the motor, first, a positively regulated power command signal is output from the positively regulated power command control means, and a predetermined positively regulated power is generated in the motor. When the elapsed time calculating means calculates the elapsed time from the generation of the regular regulation power command signal, and the elapsed time calculated by the elapsed time calculating means exceeds a predetermined reference elapsed time, the secondary braking force command control The means generates a secondary braking force that is greater than the positive regulation power.
[0032]
Thereby, even if the frequency of the modulation signal used for the pulse width modulation is high or relatively low, the secondary braking force brakes the motor following the initial positive regulation power. The braking performance can be realized, and the operational reliability is improved.
[0033]
In the motor control device according to the second aspect of the present invention, a pulse width modulated braking logic signal for braking the rotation state of the motor is used. When braking the motor, first, a positively regulated power command signal is output from the positively regulated power command control means, and a predetermined positively regulated power is generated in the motor. When the rotation speed calculation means calculates the rotation speed of the motor after the generation of the regular regulation power command signal, and the rotation speed of the motor calculated by the rotation speed calculation means falls below a predetermined reference rotation speed, the secondary control The power command control means generates a secondary braking force that is greater than the positive regulation power.
[0034]
Thereby, the same effect as the effect demonstrated regarding Claim 1 is realizable.
[Brief description of the drawings]
FIG. 1 is a block diagram showing an electrical configuration of a control device 1 according to a first embodiment of the present invention.
FIG. 2 is a block diagram illustrating an example of an electrical configuration of a motor drive control unit 4 of the control device 1;
FIG. 3 is a waveform diagram showing an operation example of the control device 1;
FIG. 4 is a block diagram showing an electrical configuration of a control device 1a according to a second embodiment of the present invention.
FIG. 5 is a waveform diagram for explaining the operation of the control device 1a.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1, 1a Control apparatus 2 Motor 3 Magnetic pole detection element 4 Motor drive control part 5 Input / output command signal control part 6 Positive control power command control part 7 Elapsed time calculation part 8 Secondary braking force command calculation part 9 Braking force command switching control part 14 Rotational speed calculation unit S1 Braking force command S3 Braking start command SP Position signals Su, Sv, Sw

Claims (2)

In a motor control device using a pulse width modulated braking logic signal for braking the rotational state of the motor,
A positively regulated power command control means for generating a positively regulated power command signal for generating a constant positively regulated power regardless of the elapsed time ;
Secondary braking force command control means for generating a secondary braking force command signal for generating a secondary braking force that increases with elapsed time;
An elapsed time calculating means for calculating an elapsed time from the generation of the regular regulation power command signal;
Braking force command switching control means for selecting a secondary braking force command signal larger than the positively regulated power command signal when the elapsed time calculated by the elapsed time calculating means exceeds a predetermined reference elapsed time; A motor control device provided. In a motor control device using a pulse width modulated braking logic signal for braking the rotational state of the motor,
A positively regulated power command control means for generating a positively regulated power command signal for generating a constant positively regulated power regardless of the rotational speed ;
Secondary braking force command control means for generating a secondary braking force command signal for generating a secondary braking force that gradually increases as the rotational speed decreases;
A rotation speed calculating means for calculating the rotation speed of the motor after the generation of the regular regulation power command signal;
Braking force command switching control means for selecting a secondary braking force command signal that is larger than the positively regulated power command signal when the rotational speed calculated by the rotational speed calculation means falls below a predetermined reference rotational speed; A motor control device provided.

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