KR20170018565A - System and method for detecting a number of rotations in motor using a ripple of motor - Google Patents

Abstract

The present invention relates to a system and a method for detecting the number of rotations of a motor using a motors ripples, which detect the number of rotations of the motor by counting square wave signals obtained by amplifying and filtering ripple signals generated from the motor when the motor is driven and comparing the ripple signals with a reference voltage signal. The system for detecting the number of rotations of a motor using ripples of the motor comprises: an amplifying unit which receives a ripple signal caused by a gap between commutators of the motor and outputs an amplification signal amplified to a predetermined amplitude or greater; a filtering delay unit which delays a phase of the amplification signal and filters the amplification signal to a low-pass signal; a comparison output unit which inputs the delayed and filtered signal as a tracking reference voltage and compares the same with the amplification signal output from the amplifying unit to output a square wave signal (PWM); and a control unit which counts the square wave signal to output the number of rotations of the motor.

Description

TECHNICAL FIELD [0001] The present invention relates to a method and a system for detecting the number of revolutions of a motor using pulsation of a motor,

The present invention relates to a method and system for detecting the number of revolutions of a motor using a pulse of a motor, and more particularly, to a method and system for detecting a number of revolutions of a motor by amplifying and filtering a ripple signal generated by a motor installed in a vehicle, And more particularly, to a method and a system for detecting the number of revolutions of a motor using pulsation of a motor so as to be able to detect the number of revolutions of the motor.

Conventionally, the number of rotations of the motor uses a Hall sensor signal generated from a motor. That is, the PWM (Pulse With Modulation) signal shown in FIG. 1 generated from the motor through the hall sensor is recognized as a signal through a normal signal determination algorithm. 1 is a diagram showing an example of recognizing a PWM signal generated through a hall sensor through a normal signal judgment algorithm.

However, there is a problem in the manufacturing process of such a motor. In order to recognize the conventional Hall sensor, we are carrying out the magnet attaching process. At this time, the deviation should be set to 15% due to the equipment problem in the process. Therefore, when the PWM signal exceeding the reference value is generated at a certain voltage, there is a problem in that the user's lost or stolen memory location is deleted.

      In addition, Hall sensors are structurally located inside the motor and are heavily influenced by heat. Therefore, there is a problem that the characteristics of the Hall sensor vary due to heat.

Korean Registered Patent No. 796,055 (Registered on Jan. 11, 2008)

SUMMARY OF THE INVENTION An object of the present invention to solve the above problems is to amplify a ripple signal generated in a motor at the time of driving a motor vehicle and to filter the rectangular wave signal obtained by comparing the ripple signal with a reference voltage signal, And to provide a method and system for detecting the number of revolutions of a motor using pulsation of a motor.

According to an aspect of the present invention, there is provided a motor rotation speed detection system using a pulse of a motor. The motor rotation speed detection system comprises: a motor for receiving a ripple signal generated by a commutator gap of a motor, An amplifying unit for outputting the amplified signal; A filtering delay unit for delaying the phase of the amplified signal and filtering the signal by a signal of a low frequency band (Low Pass); A comparison output unit that receives the filtered delayed signal as a tracking reference voltage and outputs a square wave (PWM) signal as compared with the amplified signal output from the amplifying unit; And a controller for counting the square wave signal and calculating the number of revolutions of the motor.

The amplifying unit may be configured to input the ripple signal to a positive terminal of an amplifier OP AMP, a resistor R connected between a negative terminal of the amplifier and ground, A resistor R2 having a resistance value equal to or higher than a predetermined value may be connected in parallel between the output terminal OUT and the output terminal OUT.

In addition, the filtering delay unit may delay the phase of the amplified signal by a time constant circuit in which the resistor (R3) and the capacitor (C1) are connected in parallel, and filter the amplified signal into a signal of a low frequency band.

The comparison output unit receives the amplified signal output from the amplification unit at the negative terminal of the comparator COMP and receives the filtered delayed signal at the positive terminal of the comparator to compare the two signals And can output a square wave signal.

The controller detects the first edge of the square wave signal and recognizes the first edge as a pulse signal when detecting the second edge. The controller counts each pulse signal having two edges as a period, The number of revolutions of the motor is calculated.

According to another aspect of the present invention, there is provided a method of detecting a motor speed using a pulse of a motor, the method including: (a) receiving a ripple signal generated by a commutator gap of the motor, Outputting an amplified signal amplified to a size greater than the amplified signal; (b) filtering delay the phase of the amplified signal with a low-pass signal to output a filtered delayed signal; (c) receiving a filtered delayed signal as a tracking reference voltage and comparing the amplified signal with the amplified signal to output a square wave (PWM) signal; And (d) calculating a rotational speed of the motor by counting the rectangular wave signal by the control unit.

In the step (a), a resistor (R) is connected between the amplification unit (-) terminal and ground, and a resistor (R) having a resistance value equal to or more than a predetermined value between a connection point of the resistor R2 may be connected to the (+) terminal of an amplifier (OP AMP) connected in parallel to output the amplified signal amplified by a predetermined magnitude or more to the output OUT.

In the step (b), the filtering delay unit may delay the phase by the time constant circuit connected in parallel with the resistor (R3) and the capacitor (C1) and filter the amplified signal into a signal of a low frequency band.

In the step (c), the comparison output unit receives the amplified signal at the (-) terminal of the comparator (COMP), receives the filtered delayed signal at the (+) terminal of the comparator, And output it as a square wave signal.

In the step (d), when the controller detects the first edge of the square wave signal and then detects the second edge, the controller recognizes the pulse signal as one pulse signal, The pulse signal is counted to calculate the number of revolutions of the motor.

According to the present invention, the position and speed of the motor can be controlled by using the pulsation generated by the gap of the commutator of the motor.

In addition, it is possible to solve the problems caused by the dispersion of 15% generated when the magnet is attached for the output of a conventional Hall sensor.

In addition, it is possible to solve the problem that the characteristic due to heat changes in the characteristic of the Hall sensor.

In addition, although the controllers using the pulsation of the conventional motor use only motors having a certain characteristic, the present invention can generate the same effect by using motors having a constant structure. That is, even if the structure of the motor is different, it is generated as a PWM signal by the 'tracking reference voltage', and is available to all motors.

Further, by simplifying the structure of the motor, there is an advantage that the unit cost of the overall structure is reduced due to the simplification of the motor, the reduction of the process, and the reduction of the connector and the wiring.

1 is a diagram showing an example of recognizing a PWM signal generated through a hall sensor through a normal signal judgment algorithm.
2 is a block diagram showing a circuit configuration of a motor rotation number detection system using pulsation of a motor according to an embodiment of the present invention.
3 is a diagram illustrating an example of counting each pulse signal having two edges as a period according to an embodiment of the present invention.
4 is a flowchart illustrating a method of detecting the number of revolutions of a motor using pulsation of a motor according to an embodiment of the present invention.
FIG. 5 is a diagram illustrating a waveform change of a pulse signal according to an applied voltage according to an embodiment of the present invention. Referring to FIG.
6 is a graph illustrating an example of delaying an amplified signal into a time domain and filtering the amplified signal into a frequency domain according to an embodiment of the present invention.
7 is a diagram illustrating an example of outputting an amplified signal and a filtered delayed signal as a square wave signal through a comparator according to an embodiment of the present invention.
8 is a view showing three phenomena when the motor is driven according to the embodiment of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings, which will be readily apparent to those skilled in the art to which the present invention pertains. The present invention may be embodied in many different forms and is not limited to the embodiments described herein.

In order to clearly illustrate the present invention, parts not related to the description are omitted, and the same or similar components are denoted by the same reference numerals throughout the specification.

Throughout the specification, when a part is referred to as being "connected" to another part, it includes not only "directly connected" but also "electrically connected" with another part in between . Also, when an element is referred to as "comprising ", it means that it can include other elements as well, without departing from the other elements unless specifically stated otherwise.

If any part is referred to as being "on" another part, it may be directly on the other part or may be accompanied by another part therebetween. In contrast, when a section is referred to as being "directly above" another section, no other section is involved.

The terms first, second and third, etc. are used to describe various portions, components, regions, layers and / or sections, but are not limited thereto. These terms are only used to distinguish any moiety, element, region, layer or section from another moiety, moiety, region, layer or section. Thus, a first portion, component, region, layer or section described below may be referred to as a second portion, component, region, layer or section without departing from the scope of the present invention.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. The singular forms as used herein include plural forms as long as the phrases do not expressly express the opposite meaning thereto. Means that a particular feature, region, integer, step, operation, element and / or component is specified and that the presence or absence of other features, regions, integers, steps, operations, elements, and / It does not exclude addition.

Terms indicating relative space such as "below "," above ", and the like may be used to more easily describe the relationship to other portions of a portion shown in the figures. These terms are intended to include other meanings or acts of the apparatus in use, as well as intended meanings in the drawings. For example, when inverting a device in the figures, certain parts that are described as being "below" other parts are described as being "above " other parts. Thus, an exemplary term "below" includes both up and down directions. The device can be rotated by 90 degrees or rotated at different angles, and terms indicating relative space are interpreted accordingly.

Unless otherwise defined, all terms including technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Commonly used predefined terms are further interpreted as having a meaning consistent with the relevant technical literature and the present disclosure, and are not to be construed as ideal or very formal meanings unless defined otherwise.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

2 is a block diagram showing a circuit configuration of a motor rotation number detection system using pulsation of a motor according to an embodiment of the present invention.

Referring to FIG. 2, the motor rotation speed detection system 100 using pulsation of a motor according to the present invention includes an amplification unit 110, a filtering delay unit 120, a comparison output unit 130, and a control unit 140 .

The amplification unit 110 receives a ripple / noise signal generated by a commutator gap of the motor and outputs an amplified signal amplified to a predetermined magnitude or more.

The amplifying unit 110 inputs the pulsating signal to the (+) terminal of the amplifier OP AMP and the resistor R 1 is connected between the (-) terminal of the amplifier and the ground, And a resistor R2 having a resistance value equal to or greater than a predetermined value are connected in parallel between the output terminal OUT and the output terminal OUT.

The filtering delay unit 120 delays the phase of the amplified signal and filters it by using a signal of a low frequency band (Low Pass).

In addition, the filtering delay unit 120 delays the phase of the amplified signal by a time constant circuit in which the resistor R3 and the capacitor C2 are connected in parallel, and filters the amplified signal into a signal of a low frequency band.

In addition, the filtered delayed signal is extracted from the amplification unit 110 and can be structurally corresponding to any characteristic change of the motor. As shown in FIG. 8, it can be confirmed that PWM (Pulse Width Modulation) is generated at the start, stop and stall of the motor. 8 is a view showing three phenomena when the motor is driven according to the embodiment of the present invention.

In other words, there are three kinds of phenomenon when the motor is driven. Start (?) Is an over run phenomenon for the start current, and Normal (?) Is a stable phenomenon when the load is constant. Finally, stop (?) Refers to the overrun phenomenon caused by inertia at stop.

The comparison output unit 130 receives the filtered delayed signal as a tracking reference voltage and outputs a square wave (PWM) signal as compared with the amplified signal output from the amplification unit 110.

The comparison output unit 130 receives the amplified signal output from the amplification unit 110 at the negative terminal of the comparator COMP and receives the filtered delayed signal at the positive terminal of the comparator, And outputs it as a square wave signal.

The control unit 140 counts the square wave signal to calculate the number of revolutions of the motor.

That is, the control unit 140 recognizes the square wave signal as one pulse (Pulse) signal when detecting the first edge Edge1 as shown in FIG. 3 and then detecting the second edge Edge2, The number of rotations of the motor is calculated by counting each pulse signal having the edges Edge1 and Edge2 as a period. 3 is a diagram illustrating an example of counting each pulse signal having two edges as a period according to an embodiment of the present invention.

4 is a flowchart illustrating a method of detecting the number of revolutions of a motor using pulsation of a motor according to an embodiment of the present invention.

The key of the present invention is to generate a signal which can be effectively counted by amplifying a ripple signal generated in a motor through an amplifier.

4, the motor rotation speed detection system 100 using the pulsation of a motor according to the present invention receives a ripple signal generated by a commutator gap of a motor And outputs an amplified signal amplified to a predetermined size or more (S410).

At this time, the amplifier 110 is connected to the resistor R1 between the (-) terminal and the ground, and the resistor R1 having a resistance value of 10 k? Or more between the connection point of the resistor R1 and the output terminal OUT Ripple signal such as NOISE is inputted to the (+) terminal of the amplifier OP AMP connected in parallel to the output terminal OUT.

The ripple generated in the motor is structurally generated. Structural generation means the precision of the production technology that can be produced precisely in the design of the commutator. However, this technique is incompatible with all motors. In order to overcome the difference, the reference voltage value should follow the waveform of the ripple signal generated by the motor. In this case, the same circuit can be applied to all motors.

In the case of a motor, as shown in FIG. 5, when the applied voltage is increased, the rotation speed is increased and the current flow is increased, thereby causing a DC bias change. FIG. 5 is a diagram illustrating a waveform change of a pulse signal according to an applied voltage according to an embodiment of the present invention. Referring to FIG. 5, when the reference voltage is fixed to an intermediate value and the applied voltage is slowly increased, the DC value of the pulse signal increases according to the applied voltage.

Next, the filtering delay unit 120 delays the phase of the amplified signal and filters the signal with a low-frequency band signal (Low Pass) to output a filtered delayed signal (S420).

At this time, the filtering delay unit 120 delays the phase of the amplified signal by a time constant circuit in which the resistor R3 and the capacitor C2 are connected in parallel, and filters the amplified signal into a signal of a low frequency band.

Here, the delay time? Of the filtering delay unit 120 can be calculated according to the following equation (1) when calculating the time domain of FIG. 6. 6 is a graph illustrating an example of delaying an amplified signal into a time domain and filtering the amplified signal into a frequency domain according to an embodiment of the present invention.

In Equation (1), R represents the value of the resistor R3 of the time constant circuit in which the resistor R3 and the capacitor C2 are connected in parallel, and C represents the capacitance value of the capacitor C2. For example, when R3 is 10 k? And C2 is 100 k ?, the delay time? Is 1 ms.

The filtering delay unit 120 filters the amplified signal in a low frequency band to generate a frequency signal (Freq.) In the frequency domain of FIG. 6 according to Equation (2).

Here Freq. Represents the frequency, R represents the value of the resistor R3, and C represents the capacitance value of the capacitor C2.

That is, the filtering delay unit 120 outputs the frequency of the low frequency band of the effective component through the RC low pass filter (LPF). For example, when R3 is 10 k? And C2 is 100 k?, A frequency signal of 1.5 kHz is obtained.

Next, the comparison output unit 130 receives the filtered delayed signal as a tracking reference voltage, compares it with the amplified signal, and outputs a PWM (Pulse Width Modulation) signal in operation S430.

At this time, the comparison output unit 130 receives the amplified signal ⓒ as the negative terminal of the comparator COMP as shown in FIG. 7 and inputs the filtered delayed signal ⓓ to the positive terminal of the comparator And compares the two signals and outputs them as a square wave signal (). 7 is a diagram illustrating an example of outputting an amplified signal and a filtered delayed signal as a square wave signal through a comparator according to an embodiment of the present invention. As shown in FIG. 7, it can be seen that the amplified signal (C) and the filtered delayed signal (D) remain in phase difference within 90 to 180 °.

Next, the controller 140 counts the square wave signals to calculate the number of revolutions of the motor (S440).

That is, as shown in FIG. 4, the controller 140 detects a first edge (Edge1) of a rectangular wave signal and then recognizes a second pulse (Edge2) as a pulse signal, The number of rotations of the motor is calculated by counting each pulse signal having the cycle of the edges Edge1 and Edge2.

Therefore, when the motor revolution detection system 100 using the pulsation of the motor according to the present invention is applied to a seat of an automobile, it is possible to calculate the revolution number of the motor using the pulse signal generated in the motor The seat position can be stored in the memory and the same can be applied to all controllers using a DC motor.

As described above, according to the present invention, a ripple signal generated in a motor at the time of motor driving of a vehicle is amplified, filtered, and compared with a reference voltage signal to obtain a rectangular wave signal, The motor rotation speed detection method and system using the pulsation of the motor can be realized.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the following claims and their equivalents. Only. The scope of the present invention is defined by the appended claims rather than the detailed description and all changes or modifications derived from the meaning and scope of the claims and their equivalents are to be construed as being included within the scope of the present invention do.

100: Motor rotation speed detection system using motor pulse
110:
120: Filtration delay unit
130:
140:

Claims (10)

An amplifier for receiving a ripple signal generated by a commutator gap of the motor and outputting an amplified signal amplified to a predetermined magnitude or more;
A filtering delay unit for delaying the phase of the amplified signal and filtering the signal by a signal of a low frequency band (Low Pass);
A comparison output unit that receives the filtered delayed signal as a tracking reference voltage and outputs a square wave (PWM) signal as compared with the amplified signal output from the amplifying unit; And
A control unit for counting the square wave signal to calculate the number of revolutions of the motor;
The motor rotation speed detection system using the pulsation of the motor.
The method according to claim 1,
Wherein the amplifying unit inputs the ripple signal to a positive terminal of an amplifier OP AMP and a resistor R is connected between a negative terminal of the amplifier and a ground, And a resistor (R2) having a resistance value equal to or greater than a predetermined value is connected in parallel between the output terminal (OUT) and the output terminal (OUT).
The method according to claim 1,
Wherein the filter delay unit delays the phase of the amplified signal by a time constant circuit in which a resistor (R3) and a capacitor (C1) are connected in parallel and filters the amplified signal by a signal of a low frequency band. Detection system.
The method according to claim 1,
The comparison output unit receives the amplified signal output from the amplification unit at the negative terminal of the comparator COMP and receives the filtered delayed signal at the positive terminal of the comparator to compare the two signals, The motor rotation speed detection system using the pulse of the motor.
The method according to claim 1,
The control unit recognizes the first edge of the rectangular wave signal as a pulse when the second edge is detected, counts each pulse signal having two edges as a period, And the rotation speed of the motor is calculated.
(a) receiving a ripple signal generated by a commutator gap of the amplifying unit motor and outputting an amplified signal amplified to a predetermined magnitude or more;
(b) filtering delay the phase of the amplified signal with a low-pass signal to output a filtered delayed signal;
(c) receiving a filtered delayed signal as a tracking reference voltage and comparing the amplified signal with the amplified signal to output a square wave (PWM) signal; And
(d) calculating a rotational speed of the motor by counting the rectangular wave signal by the control unit;
The motor rotation speed detection method using the pulsation of the motor.
The method of claim 6,
In the step (a), a resistor (R) is connected between the amplifying unit (-) terminal and ground, and a resistor (R2) having a resistance value equal to or higher than a predetermined value is connected between a connection point of the resistor (R) And the amplified signal amplified to a predetermined magnitude or more is output to the output terminal (OUT) by receiving the pulsation signal at a (+) terminal of an amplifier (OP AMP) connected in parallel. Detection method.
The method of claim 6,
Wherein the filtering delay unit delays the phase of the amplified signal by a time constant circuit connected in parallel with the resistor (R3) and the capacitor (C1), and filters the amplified signal by a signal of a low frequency band. Detection Method of Motor Speed Using Pulse.
The method of claim 6,
Wherein the comparison output section receives the amplified signal from the negative terminal of the comparator COMP and receives the filtered delayed signal from the positive terminal of the comparator and compares the two signals to obtain a square wave And outputting the signal as a signal.
The method of claim 6,
In the step (d), when the controller detects the first edge of the rectangular wave signal and then detects the second edge, the controller recognizes the pulse signal as one pulse signal, And counting the number of revolutions of the motor to calculate the number of revolutions of the motor.

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