KR101865325B1

KR101865325B1 - Method for detecting rotor position of BLDC motor

Info

Publication number: KR101865325B1
Application number: KR1020160181367A
Authority: KR
Inventors: 이성용
Original assignee: 한화시스템 주식회사
Priority date: 2016-12-28
Filing date: 2016-12-28
Publication date: 2018-07-04

Abstract

A two-axis gimbal system according to an embodiment of the present invention includes first and second BLDC motors having driving shafts perpendicular to each other, a BLDC motor driving control unit controlling driving of the first and second BLDC motors, And a 2-axis gimbal device which is driven by a 2-axis BLDC motor. The position of the rotor may be configured to detect rotor position data of any one of the 3 phases of the first and second BLDC motors And a rotor position data calculator for calculating rotor position data of the remaining phases based on the one-phase rotor position data detected by the data detector and the rotor position data detector.
The BLDC motor drive control unit may further include an angular velocity calculating unit that calculates angular velocity data of the two-axis magnetic gimbal device based on the rotor position data detected by the rotor position data detector and the rotor position data calculated and calculated by the rotor position data detector .

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of detecting a rotor position of a BLDC motor for two-

The present invention relates to a method for detecting the position of a rotor of a BLDC motor.

More specifically, the present invention relates to a method for controlling a biaxial magnetization device by detecting the position of a rotor of a BLDC motor using only one terminal voltage component among three-phase terminal voltages.

The two-axis gimbal device includes a servo controller for driving the two-axis gimbal device. On the other hand, the servo controller includes a position loop and a velocity loop.

The velocity loop of the servo controller measures the yaw and pitch of the two-axis gimbal device using a gyroscope sensor.

On the other hand, the position loop of the servo controller receives the angle command and the resolver signal and drives the BLDC motor to perform tracking control of the dual axis jigging device.

Since the BLDC motor must change the phase current of the motor according to the position of the rotor, sensors such as Hall-sensors or encoders that can detect the position of the rotor are essential.

However, when the sensor for detecting the position of the rotor is attached to the BLDC motor as described above, there are many problems such as an increase in the overall price, an increase in volume, restrictions on the use environment, and electromagnetic interference.

In order to solve this problem, a sensorless method in which a sensor is removed in a conventional method using a sensor is used. For example, the position of the rotor of the BLDC motor was indirectly detected using a circuit for detecting the terminal voltage on the non-excitation phase.

On the other hand, since the configuration of the circuit for detecting the terminal voltage is relatively simple and it is directly detected by the analog circuit, the burden on the control unit is reduced, and the advantage is obtained in real time detection and control.

Therefore, the rotor position of the remaining phase can be calculated only by detecting the rotor position of one phase of the BLDC motor without using a separate sensor, and can be used for controlling the two-axis gimbal device.

The present invention provides a method for measuring a terminal voltage component of only one phase and detecting the position of a rotor of a BLDC motor based on the measured terminal voltage component.

A two-axis gimbal system according to an embodiment of the present invention includes first and second BLDC motors having driving shafts perpendicular to each other, a BLDC motor driving control unit controlling driving of the first and second BLDC motors, And a 2-axis gimbal device which is driven by a 2-axis BLDC motor. The position of the rotor may be configured to detect rotor position data of any one of the 3 phases of the first and second BLDC motors And a rotor position data calculator for calculating rotor position data of the remaining phases based on the one-phase rotor position data detected by the data detector and the rotor position data detector.

The BLDC motor drive control unit may further include an angular velocity calculating unit that calculates angular velocity data of the two-axis magnetic gimbal device based on the rotor position data detected by the rotor position data detector and the rotor position data calculated and calculated by the rotor position data detector .

Meanwhile, the first BLDC motor may rotate the biaxial magnetization device in the Yaw direction, and the second BLDC motor may rotate the biaxial magnetization device in the Pitch direction.

On the other hand, the rotor position data detecting section includes a voltage dividing resistor for dividing the terminal voltage on any one of the three phases of the first and second BLDC motors, a terminal voltage divided by the voltage dividing resistor to a predetermined frequency And a zero point comparing circuit for comparing the output value of the integrating circuit with a zero point, wherein the voltage dividing resistor, the active filter, the integrating circuit, and the zero point The comparator can detect the rotor position data on any one of the three phases of the BLDC.

The rotor position data calculator includes a PLL circuit, a binary counter, a Johnson counter, and a logic combination circuit. The rotor position data calculator calculates a rotor position data based on one rotor position data detected by the rotor position data detector, The position data can be calculated.

On the other hand, the angular velocity calculating unit may differentiate the rotor position data detected and calculated by the rotor position data detecting unit and the rotor position data calculating unit to calculate the yaw and pitch angular speeds of the two-axis gimbal device.

Meanwhile, the BLDC motor drive control unit may control the first and second BLDC motors based on the target angle value generated by the image signal processing obtained through the external image detector and the angular velocity values of the two-axis gimbal device received from the angular velocity calculating unit, The driving of the motor can be controlled.

The present invention can control the biaxial jigging device by detecting the position of the rotor of the BLDC motor without a separate sensor.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a general configuration diagram of a biaxial gimbal system according to an embodiment of the present invention; FIG.
2 is a circuit diagram of a rotor position data detecting unit according to an embodiment of the present invention.
3 is a block diagram of a rotor position data calculation unit according to an embodiment of the present invention.
4 is a specific embodiment of the rotor position data detecting unit of the present invention.
5 and 6 are specific embodiments of the rotor position data calculation unit of the present invention.
7 is a configuration diagram, a timing diagram, and a counter truth table of the Johnson counter according to the embodiment of the present invention

Hereinafter, 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. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and similar parts are denoted by like reference characters throughout the specification.

Terms including ordinals, such as first, second, etc., may be used to describe various elements, but the elements are not limited to these terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component. The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise.

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. The word " step (or step) " or " step " used to the extent that it is used throughout the specification does not mean " step for.

While the present invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiments. Also, in certain cases, there may be a term selected arbitrarily by the applicant, in which case the meaning thereof will be described in detail in the description of the corresponding invention. Therefore, the term used in the present invention should be defined based on the meaning of the term, not on the name of a simple term, but on the entire contents of the present invention.

1. Configuration of a two-axis gimbal system according to an embodiment of the present invention

1 is a configuration diagram of a biaxial gimbal system according to an embodiment of the present invention.

The biaxial gimbal system of the present invention includes first and second BLDC motors 210 and 220 having driving shafts perpendicular to each other, a BLDC motor driving control unit 500 for controlling driving of the first and second BLDC motors 210 and 220, And a biaxial jigging device 100 driven by the first and second BLDC motors 210 and 220.

Each of the first and second BLDC motors 210 and 220 includes a rotor position data detector 300 for detecting rotor position data of one phase, And may be connected to the rotor position data calculation unit 400 for calculating the position data.

The BLDC motor drive control unit 500 includes a rotor position data detector 300 and a rotor position data calculator 400 connected to the first and second BLDC motors 210 and 220 for detecting and calculating (Not shown) for calculating the angular velocity data of the two-axis firing device 100 based on the rotor position data.

More specifically, the first BLDC motor 210 rotates the biaxial jigging device 100 in the Yaw direction and the second BLDC motor 220 rotates the biaxial jigging device 100 in the pitch direction have.

2 is a circuit diagram of the rotor position data detecting unit 300 of each of the first and second BLDC motors 210 and 220 according to the embodiment of the present invention.

Hereinafter, the rotor position data detector 300 of the present invention will be described with reference to FIG.

The rotor position data detector 300 according to the embodiment of the present invention includes a voltage divider resistor for dividing the terminal voltage on any one of the three phases of each of the first and second BLDC motors 210 and 220, And a zero point comparing circuit for comparing the output value of the integrating circuit with a zero point, wherein the zero point comparing circuit comprises: The voltage divider resistor, the active filter, the integrator circuit and the zero point comparator circuit can detect the rotor position data on any of the three phases of the BLDC motor.

The rotor position data calculation unit 400 may calculate rotor position data for the remaining phases from any one of the three rotor phase positions of the BLDC motor detected as described above.

More specifically, FIG. 3 is a specific configuration diagram of the rotor position data calculation unit 400 according to the embodiment of the present invention.

Hereinafter, the rotor position data calculation unit 400 of the present invention will be described with reference to FIG.

The rotor position data calculation unit 400 may include a PLL circuit, a binary counter, a Johnson counter, a logic combination circuit, and the like.

On the other hand, the PLL circuit can multiply the detected one-phase rotor position data by six.

On the other hand, the binary counter can rectify the rotor position data of one phase multiplied by one and generate rotor phase position data of one phase.

The rotor position data of one phase that is rectified in this manner can be calculated as the rotor position data of the remaining phases through the Johnson counter and the logic combination circuit.

Hereinafter, specific embodiments for detecting the above-described one-phase rotor position data and calculating rotor position data for the remaining phases from one-phase rotor position data will be described with reference to the drawings.

A method of detecting rotor position data of one phase according to an embodiment of the present invention is shown in Fig. 4,

More specifically, when a terminal voltage of one phase is detected as shown in FIG. 4 (a), the terminal voltage of the phase passes through the active filter to obtain data as shown in FIG. 4 (b).

If the data of FIG. 4 (b) is integrated through the integration circuit, the signal as shown in FIG. 4 (c) can be obtained.

On the other hand, when the signal of FIG. 4 (c) is compared with the zero point detection circuit, the rotor position data of one phase as shown in FIG. 4 (d) can be obtained.

Meanwhile, the method of calculating the rotor position data of the remaining phases from the rotor position data of one phase according to the embodiment of the present invention is as shown in Fig. 5 and Fig.

More specifically, if the rotor position data of one phase as shown in FIG. 5 (a) is multiplied by six through the PLL circuit, data as shown in FIG. 5 (b) can be obtained.

On the other hand, if the data of FIG. 5 (b) is rectified through the binary counter, data as shown in FIG. 5 (c) can be obtained.

5 (c), the Johnson counter and the combinational logic circuit can generate the rotor position data of the remaining phases as shown in FIG.

For example, an exemplary three-stage Johnson counter has a total of six modules, which may represent an equivalent coefficient value of 0 to 5 for a binary number.

7 is a block diagram of the Johnson counter, a timing diagram, and a counter truth table.

Referring to FIG. 7, the circuit configuration of the Johnson counter is such that the inverted signal (Q) of each flip-flop enters the K input of the next-stage flip-flop and the non-inverted signal Q enters the J input. The flip-flop output Q of the last stage is connected to K of the first stage flip-flop, and Q is connected to the first stage J.

The Johnson counter thus constructed assumes that all the flip-flops are reset first, and if the clock is applied thereto, since the inverted signal of the last-stage flip-flop is 1 at the first timing, the first flip-flop is set and the remaining is cleared .

In the second clock, the inverting signal of the last stage flip-flop is still 1, so that the first flip-flop maintains the set state and the second flip-flop changes from the cleared state to the set state.

In the third clock, the inverting signal of the last flip-flop is still 1, so that the first flip-flop maintains the set state and the second flip-flop also maintains the set state.

Then, when the last third flip-flop is set, the inverted signal of the last-stage flip-flop becomes 0 in the fourth clock, so that the first flip-flop is cleared to 0 and the remaining flip-flops maintain the set state.

At the fifth timing, since the inverting signal of the last stage flip-flop is 0, the first flip-flop maintains the state of 0, and the second flip-flop changes from the set state to the clear state since the inverted signal of the first flip- .

At the sixth timing, all flip-flops are cleared.

That is, the output waveform of each flip-flop becomes a waveform shifted by the front-end flip-flop and can be operated as an N-1 counter conversion circuit by a combination of output waveforms at each stage.

Meanwhile, the angular velocity calculating unit (not shown) differentiates the rotor position data detected and calculated by the rotor position data detector 300 and the rotor position data calculator 400, Pitch angular velocity can be calculated.

On the other hand, the BLDC motor drive control unit 500 controls the driving of the BLDC motor based on the target angle value generated by the image signal processing obtained through the external image detector and the angular velocity value of the 2-axis gimbal device received from the angular velocity calculating unit The driving of the first and second BLDC motors 210 and 220 can be controlled.

The rotor position data detector 300, the rotor position data calculator 400, and the angular velocity calculator (not shown) may be provided for the first and second BLDC motors 210 and 220, respectively.

That is, the rotor position data detector 300 of the first BLDC motor 210, the rotor position data calculator 400, the rotor position data detector 300 of the angular velocity calculator and the second BLDC motor 220, The rotor position data calculation unit 400, and the angular velocity calculation unit may be separately provided.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention.

100: Two-axis gimbal device
210: first BLDC motor
220: second BLDC motor
300: Rotor position data detector
400: Rotor position data calculation unit
500: BLDC motor drive control section

Claims

First and second BLDC motors whose drive axes are perpendicular to each other;
A BLDC motor drive control unit for controlling driving of the first and second BLDC motors; And
A 2-axis gimbal device moved by the first and second BLDC motors;
And a biaxial gimbal system,
A rotor position data detector for detecting rotor position data of any one of the three phases of the first and second BLDC motors; And
A rotor position data calculation unit for calculating rotor position data of the remaining phases based on the phase position rotor position data detected by the rotor position data detection unit;
And,
The BLDC motor drive control unit includes:
Further comprising an angular velocity calculating unit for calculating angular velocity data of the two-axis magnetizing device based on the rotor position data detecting unit and the rotor position data detected and calculated by the rotor position data calculating unit,
Wherein the rotor position data detecting unit comprises:
A voltage dividing resistor for dividing the terminal voltage on any one of the three phases of each of the first and second BLDC motors;
An active filter for blocking a terminal voltage divided by the voltage-dividing resistor to a predetermined frequency or less;
An integrating circuit for integrating the signal passed through the active filter; And
A zero point comparing circuit for comparing the output value of the integrating circuit with a zero point;
And,
Detecting the rotor position data on any one of the three phases of the BLDC from the voltage dividing resistor, the active filter, the integrating circuit and the zero point comparing circuit.
The rotor position data calculator
A PLL circuit for multiplying the detected one-phase rotor position data by six;
A binary counter for rectifying rotor position data of one phase multiplied by one and generating rectified rotor phase position data; And
A Johnson counter and a logic combination circuit for calculating rotor position data of the remaining phases on the basis of the rectified one-
And a biaxial gimbal system.

The method according to claim 1,
The first BLDC motor
The two-axis gimbal device is rotated in the Yaw direction,
The second BLDC motor
And the biaxial magnetization device is rotated in the Pitch direction.

delete

The method according to claim 1,
The angular velocity calculating unit may calculate,
Wherein the yaw and pitch angular velocities of the two-axis gimbal device are calculated by differentiating the rotor position data detected and calculated by the rotor position data detector and the rotor position data calculator.

The method according to claim 1,
The BLDC motor drive control unit includes:
And controls driving of the first and second BLDC motors based on a target angle value generated by the image signal processing obtained through the external image detector and an angular velocity value of the dual axis gimbal device received from the angular velocity calculating unit 2-axis gimbal system.