KR101726684B1 - Method and apparatus for driving alternating-current motor - Google Patents

Abstract

A method and apparatus for driving an alternating-current motor are disclosed. A method of driving an alternating-current motor according to an embodiment of the present invention includes steps (a) and (b) as a method of driving the alternating-current electric motor while periodically determining the rotor angle of the alternating-current electric motor. Step (a), the excitation current voltage of d ^S for in the stationary coordinate-q ^S voltage for the rotational force generated in the axial voltage and the stationary coordinate-doedoe by the shaft voltage that the alternating-current electric motor drive, the polarity combination in controlling the injection period the four pairs of each other d ^S-axis and the q ^S-axis injection voltage are applied sequentially. Step (b), control injection in the cycle, q of current unit of period ^S-axis d ^S of the previous unit period from the value of the injection current - the value of the axial injection current subtraction result, and the present unit period d ^S-axis The rotor angle in the current unit period is obtained by adding the value of the injection current and the value of the q ^S - axis injection current in the previous unit period.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an alternating-

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for driving an alternating-current motor, and more particularly, to a method and apparatus for driving an alternating-current motor while periodically determining an angle of a rotor of the alternating-current motor.

In the driving method of a general AC motor, d ^S of the synchronous coordinate system and the q-axis ^S-axis target current values are used.

Therefore,, d ^S in the still coordinate system based on the current angle of the rotor-feeds back the driving current values is converted into axial-axes driving current value ^S d in synchronization coordinate-axis and q-axis and the q ^{S S.} Further, according to the current rotor angle, d ^S of the synchronous coordinate system to thereby convert axis control voltage values, perform the control-the-axis control voltage d ^S in the stationary coordinate-axis and the q ^S-axis and the q ^S .

Therefore, it is important to precisely grasp the current rotor angle. For this purpose, resolvers are used in the past. For example, referring to Korean Patent Registration No. 0176469 (Applicant: Samsung Electronics Co., Ltd., name of invention: phase offset correction method of servo motor), a resolver is attached to a servo motor to measure the position of the rotor Technology is disclosed. Here, the resolver generates position data of the rotor.

Therefore, according to the conventional method and apparatus for driving an alternating-current motor as described above, there is a problem that the size of a driving apparatus for the alternating-current motor is increased and manufacturing cost is increased by using an additional rotor-position sensing apparatus such as a resolver.

For example, resolvers, connectors and cables for signal connections, and devices (RDC) and circuits that process output signals from resolvers must be added.

Korean Patent Registration No. 0176469 (Applicant: Samsung Electronics Co., Ltd., name of invention: method of compensating phase offset of servo motor)

The embodiment of the present invention can detect the position of the rotor internally without using an additional rotor-position sensing device such as resolver in the method and apparatus for driving the AC motor, And to reduce manufacturing cost.

According to an aspect of the present invention, there is provided a method of driving an alternating-current motor that periodically obtains a rotor angle of an alternating-current motor and includes steps (a) and (b).

Wherein in step (a), the excitation current voltage of d ^S for in the stationary coordinate-q ^S voltage for the rotational force generated in the axial voltage and the stationary coordinate-doedoe which the alternating current motor driven by the shaft voltage, polarity control infusion period the combination of four pairs of different ^S d - ^S-axis and the q - axis injection voltage are applied sequentially.

In the step (b), with a period of the control injection, q of current unit of period ^S-axis d ^S of the previous unit period from the value of the injection current - the value of the axial injection current subtraction result, and the present unit period d ^S - The rotor angle in the current unit period is obtained according to the result of addition of the value of the axial injection current and the value of q ^S - axis injection current in the previous unit period.

Further, in the above-mentioned steps (a) and the step (b), the control injection period is four unit periods have been set by As the quarter, the four unit periods q ^S in each-axis injection current and d ^S-axis injecting currents of d ^s 4 pairs in said fourth unit cycle-axis and the q ^s-axis injection voltage and so on are further shed current to the stator by injecting as sequentially.

Further, in the above step (b), in order to apply the relation of voltage and current caused by the inductance of the alternating current, q ^S at the current unit of cycle - in a previous unit period in the axis value of the injection current d ^S-axis injection current the subtraction equation for subtracting the value is set, d ^S of the current unit cycle - are the axial adding equations for adding the value of the injection current set-q ^S in the previous unit period from the value of the axial injection current .

The step (b) may also include steps (b1) and (b2).

In the step (b1), q ^S at the current unit of cycle-axis value of the injection current, d ^S of the previous unit period - the value of the axial injection current, d ^S at the current unit of cycle-axis value of the injection current, and The value of q ^S - axis injection current in the previous unit cycle is measured.

In the step (b2), the sine component and the cosine component of the rotor angle are obtained by substituting the measured injection current values into the subtraction equation and the addition equation.

According to another aspect of the present invention, there is provided a driving apparatus for an alternating-current motor that drives the alternating-current motor while periodically determining a rotor angle of the alternating-current motor, the apparatus may include a control unit and a driving unit.

The driving unit drives the AC electric motor in accordance with an applied voltage from the control unit.

The control unit includes a drive control unit and a rotor position detection unit.

The drive control unit, woman d ^S the commutation voltage for the in-rotating coordinates - q ^S voltage for the rotational force generated in the axial voltage and the still coordinate system, but by the shaft voltage driving the alternating current motor, the polarity combination in controlling the injection period and sequentially applying voltage injection axis - different four pairs of ^S d-axis and q ^S.

The rotor position detecting unit, with a period of the control injection, the present unit period q ^S-axis d ^S of the previous unit period from the value of the injection current - a result of subtracting the value of the axial injection current, and the current unit period d ^S - Calculate the rotor angle in the current unit period according to the result of adding the value of the axis injection current and the value of q ^S - axis injection current in the previous unit period.

In addition, the control injection period is set four unit periods by As the quarter are, q ^S at each of the four units of period-axis injection current and d ^S-axis injection current of the d 4 pairs in said fourth unit period ^S - q-axis and the ^S - axial injection voltage to be further flowed to the stator by injecting as sequentially.

In addition, the time from an electronic position detector, to become the relation of voltage and current caused by the inductance of the alternating current are applied, q ^S at the current unit of cycle - in a previous unit period in the axis value of the injection current d ^S-axis injection current the equation of the subtraction for subtracting a value is applied, d ^S of the current unit period - q ^S in the previous unit period from the value of the injection current axis - the axis added to the equation for adding the value of the injection current is applied.

Further, when the three-phase alternating voltage is applied to the stator of the alternating-current motor, the rotor of the alternating-current motor can be rotated. Here, the driving unit may include a driving voltage converting unit and a pulse width modulating unit.

The driving voltage converting unit converts the applied voltages (V ^s _dqs ), which are the d ^s -axis voltage (V ^s _ds ) and the q ^s -axis voltage (V ^s _qs ) from the control _unit , into a three-phase AC voltage.

The pulse width modulator applies a three-phase AC voltage from the drive voltage converter to the stator of the AC motor by pulse width modulation.

The drive control unit may include a first feedback current conversion unit, a second feedback current conversion unit, a first current subtraction unit, a proportional-integral control unit, a forward control voltage generation unit, a first voltage addition unit, a control voltage conversion unit, And a second voltage adder.

The first return current converter comprises: d ^S in the still coordinate system, detects a three-phase drive current flowing in the stator of the alternating-current motor-driven shaft calculate the current values (i ^S _dqs) - ^S-axis and q.

_r)에 따라, 상기 제1 귀환 전류 변환부로부터의 상기 정지 좌표계에서의 d^S-축 및 q^S-축 구동 전류 값들(i^S _dqs)을 동기 좌표계에서의 d^S-축 및 q^S-축 구동 전류 값들(i^r _dqs)로 변환한다.The second feedback current converter converts the input rotor angle

according to _r), the first of d ^S in the still coordinate system from the return current converter-axis and the q ^S - in a shaft drive current values (i ^S _dqs) the synchronous coordinate system, d ^S-axis and the q ^S-axis To drive current values (i ^r _dqs ).

The first current subtracting portion, in synchronization coordinate system d ^S-axis and the q ^S-axis target current values (i ^{r *} _dqs) and the first 2 d ^S from the negative feedback current conversion-axis and the q ^S-axis drive current And generates error current values that are difference values of the values (i ^r _dqs ).

The proportional-integral control unit performs proportional-integral control on the error current values from the first current subtracter to obtain d ^s -axis and q ^s -axis feedback control voltage values (V ^r _dqsfb ) in the synchronous coordinate system.

The forward control voltage generation section ^S d in synchronization with the coordinate system that is consistent with the intrinsic properties of the alternating current motor-shaft to generate a forward control voltage values (V ^r _dqsfb) - ^S-axis and q.

From the integral control unit d ^S - - wherein the first voltage adder unit the proportional-axis and the q ^S-axis feedback control voltage values (V ^r _dqsfb) and d ^S from the forward control voltage generation section-axis and the q ^S-axis forward The control voltage values (V ^r _dqsfb ) produce the resulting d ^s -axis and q ^s -axis control voltage values (V ^r _dqsf ).

_r)에 따라, 상기 제1 전압 가산부로부터의 동기 좌표계에서의 d^S-축 및 q^S-축 제어 전압 값들(V^r _dqsf)을 정지 좌표계에서의 d^S-축 및 q^S-축 제어 전압 값들(V^S _dqsf)로 변환시킨다.The control voltage converter converts the input angle of the rotor

_r), the d ^S in the synchronous coordinate system from the first voltage addition unit according to the-axis and q ^S-axis of the d ^S in control voltage values (V ^r _dqsf) a stationary coordinate-axis and the q ^S-axis control voltage Values (V ^S _dqsf ).

The injection produces a voltage axis (V ^S _dqsh) sequentially-axis and the q ^S - the injection voltage generator comprises the d ^S of the injection period the control polarity combined with different four pairs in.

It said second voltage addition unit of d ^S in the rotating coordinates from said control voltage converting unit-axis and the q ^S-axis control voltage values (V ^S _dqsf) and the d ^S in the stationary coordinate from the injection voltage generator - ^s-axis and the q - axis thereby enter the injection voltage values (V ^s _dqsh) of the applied voltage of the addition result ^(s _dqs V) to the driving voltage conversion unit in the drive unit.

Meanwhile, the rotor position detecting unit may include a signal processing unit, a rotor angle calculating unit, and a filter unit.

The signal processor, d ^S from the first feedback current converter-axis and the q ^S-axis drive currents d ^S from the (i ^S _dqs), and the injected voltage generation section-axis and the q ^S-axis injection It receives the voltages (V ^s _dqsh), q ^s at the current unit of cycle-axis d ^s of the previous unit period from the value of the injected current-axis results of the data obtained by subtracting the value of the injection current (Dat1), and the current and it outputs the data (Dat2) the result of adding the value of the injected current at the same time shaft - q ^S in the previous unit period from the value of the axial injection current - d ^S in the unit period.

_rCal)를 구한다.The rotor angle calculation unit calculates a sine component of the rotor angle and a sine component of the rotor angle by substituting the subtraction result data (Dat1) and the addition result data (Dat2) from the signal processing unit into the subtraction equation and the addition equation, respectively. (2) in the current unit cycle according to a sine component and a cosine component of the obtained rotor angle,

_rCal ).

_rCal)의 신호의 노이즈 성분을 제거하면서 회전자 각도(

_r)를 최종적으로 구하고, 상기 최종적으로 구해진 회전자 각도(

_r)를 상기 구동 제어부 내의 상기 제2 귀환전류 변환부 및 상기 제어 전압 변환부에 각각 제공한다.The filter unit may be configured to have a rotor angle of twice as large as the angle

_rCal ) while removing the noise component of the signal of the rotor

_r ) is finally obtained, and the finally obtained rotor angle (

_r ) to the second feedback current converting unit and the control voltage converting unit in the drive control unit, respectively.

Further, the signal processing unit included in the rotor position detection unit may include a first unit period delay unit, a polarity discriminator, a band pass filter, a second unit period delay unit, a second current subtractor, a current addition unit, A multiplier, and a second multiplier.

The first unit period delay unit from the injection voltage generating portion d ^S - axis and q ^S - axial injection voltage values (V ^S _dqsh) to by as a unit by delayed cycle output, of d ^S in the current unit of cycle - axis and q ^S -axis generate the injection voltage values (V ^S _dqsh ).

The polarity discriminating unit, the first of d ^S in the current unit period from the sub-unit period delay-axis and the q ^S-axis injection voltage values (V ^S _dqsh) the input received, d ^S at the current unit of cycle-axis injection The polarity signal Sig D of the voltage value and the polarity signal Sig Q of the q ^S -axis injection voltage value.

The band-pass filter, wherein the 1 d ^S from the negative feedback current conversion-axis and the q ^S-axis drive currents (i ^S _dqs) of d ^S in the period the current unit by performing a band filtering on-axis It generates an-axis value of an injection current _{^{(i S qsh (j + 1}} )) - the value of the injection current _{^{(i S dsh (j + 1}} )) , and ^S q.

The second unit period delay unit, the bandpass d ^S of the current unit period from the filter - the value of the axial injection current _{^{(i S dsh (j + 1}} )) and the q ^S-axis value of the injection current (i ^S _qsh (j + 1)) a unit period by, d ^S of the current unit period by as by the output delay - the value of the axial injection current (i ^S _dsh (j + 1)) and the q ^S-axis value of the injection current ( the axis value of the injection current _{^{(i S qsh (j))}} - i S qsh (j + 1)) d S of the previous unit period for the - value of the axial injection current (i ^S _dsh (j)) and a q ^S .

Wherein the second current subtracting unit subtracts the value of the q ^S -axis injection current (i ^S _qsh (j + 1)) in the current unit period from the band pass filter in the previous unit period from the second unit- of d ^S - subtracting the value of the axial injection current (i ^S _dsh (j)), and outputs the value of the subtraction result.

The current adding unit, wherein in a previous unit period from the sub-second unit period delay q ^S-axis value of the injection current (i ^S _qsh (j)) and the d ^S in the current unit period from the bandpass filter - Adds the value of the axis injection current (i ^S _dsh (j + 1)), and outputs the value of the addition result.

The first multiplication unit, and the second of d ^S from the subtraction result and the polarity determining unit from the current subtraction section-axis receives the injection voltage polarity signal (Sig D) of the second subtracted from the current subtraction unit the resulting ^S d - axis is multiplied by the polarity of the injection voltage and generates data (Dat1) of the subtraction result.

Wherein the second multiplier receives the addition result from the current addition unit and the polarity signal (Sig Q) of the q ^S -axis injection voltage value from the polarity determination unit, and adds q ^S - The data (Dat1) of the addition result is generated by multiplying the polarity of the axial injection voltage value.

According to an embodiment of the present invention, the control in the injection cycle, the polarity combination with each other pair of the other 4 ^S d - ^S-axis and the q - axis injection voltage are applied sequentially.

Further, in the control injection cycle, q ^S of the current unit of cycle-previous unit period in the axis value of the injection current d ^S - the value of the axial injection current subtraction result, and the present unit period d ^S - the axial injection current And the value of q ^S - axis injection current in the previous unit period are added, the rotor angle in the current unit period can be obtained.

That is, the rotor angle in the current unit cycle can be obtained by substituting the subtraction result and the addition result into the relational expression of the voltage and current by the inductance of the AC motor.

Therefore, since the rotor position can be internally detected without using an additional rotor-position sensing device such as a resolver, the size and manufacturing cost of the drive device of the AC motor can be reduced.

1 is a block diagram illustrating a method and apparatus for driving an alternating-current motor according to an embodiment of the present invention.
FIG. 2 is a graph showing the inductance of the induction motor according to the rotor angle, which is a principle for deriving the embodiment of FIG.
Axis control voltage value _{^{(V S dsf), q S}} - - 3 is d ^S from the control voltage converting unit in accordance with the control cycle of the pulse width modulation (PWM) carrier signal in the driving apparatus of the alternating current motor of Figure 1. Figure axis control voltage value (V ^S _qsf), and further d ^S from the injection voltage generating unit - is a timing chart showing the injection axis voltage value (V ^S _qsh) - injection axis voltage value (V ^S _dsh) and ^S q.
4 is a control in Fig. 3 in the injection period d ^S - axis and the q ^S - - No. 1 d ^S with respect to the axis control voltage values (V ^S _dqsf) - axis and the q ^S the axial injection voltage (V ^S _dqsh1), the 2 d ^s - axis and the q ^s - axial injection voltages (V ^s _dqsh2), the 3 d ^s - axis and the q ^s - axial injection voltages (V ^s _dqsh3), and a 4 d ^s - axis and the q ^s - Is a vector diagram showing that the axial injection voltages (V ^s _dqsh4 ) are generated per unit period.
5 is a block diagram showing the internal configuration of the rotor position detection unit of FIG.
6 is a block diagram showing an internal configuration of the signal processing unit of FIG.

The following description and accompanying drawings are for understanding the operation according to the present invention, and parts that can be easily implemented by those skilled in the art can be omitted.

Furthermore, the specification and drawings are not intended to limit the present invention, and the scope of the present invention should be determined by the claims. The terms used in the present specification should be construed to mean the meanings and concepts consistent with the technical idea of the present invention in order to best express the present invention.

For reference, in the present specification, drawings and claims, the superscript s denotes a stationary coordinate system, the superscript r denotes a synchronous coordinate system, and the subscript s denotes a stator.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

1 is a block diagram illustrating a method and apparatus for driving an alternating-current motor according to an embodiment of the present invention.

FIG. 2 is a graph showing the inductance of the induction motor according to the rotor angle, which is a principle for deriving the embodiment of FIG.

Axis control voltage value _{^{(V S dsf), q S}} - - 3 is d ^S from the control voltage converting unit in accordance with the control cycle of the pulse width modulation (PWM) carrier signal in the driving apparatus of the alternating current motor of Figure 1. Figure axis control voltage value (V ^S _qsf), and further d ^S from the injection voltage generating unit - is a timing chart showing the injection axis voltage value (V ^S _qsh) - injection axis voltage value (V ^S _dsh) and ^S q.

4 is a control injection of Figure 3 in the period d ^S - axis and the q ^S - - axial injection voltages (V ^S _dqsh1), claim 1 d ^S with respect to the axis control voltage values (V ^S _dqsf) - axis and the q ^S claim 2 d ^s - axis and the q ^s - axial injection voltages (V ^s _dqsh2), the 3 d ^s - axis and the q ^s - the axial injection voltage (V ^s _dqsh3), and a 4 d ^s - axis and the q ^s - It is a vector diagram showing that the axial injection voltages (V ^s _dqsh4 ) are generated per unit period.

Referring to FIGS. 1 to 4, a driving apparatus according to an embodiment of the present invention includes an AC motor 11, for example, a rotor angle of an Interior-Permanent Magnet Synchronous Motor (IPMSM) And includes a control unit 12 and a driving unit 13, which drives the AC electric motor 11. [

The driving unit 13 drives the AC electric motor 11 in accordance with the applied voltage (V ^S _dqs ) from the control unit 12.

The control unit 12 includes a drive control unit 121 and a rotor position detection unit 122.

But applying an axial voltage (V ^S _dqs) to the drive (13), - the drive control system 121 includes a d ^S voltage for the exciting current in still coordinate system - q ^S, as for the rotational force voltage generated in the axial voltage and the stationary coordinate It is applied to the shaft of the injection voltage (V ^s _dqsh) sequentially controlling the injection period (Tci in Fig. 3) polar combination of different pairs from the 4 ^s d-axis and q ^s.

_r)를 구한다.A rotor position detecting section 122, control injection period in (Tci), the current unit period (△ T) q ^S - axis of the previous unit period from the value of the injection current (i ^S _qsh) d ^S - the axial injection current (I ^S _dsh ) of the current unit period and the value of the d ^S -axis injection current (i ^S _dsh ) of the current unit period and the value of the q ^S -axis injection current (i ^S _qsh ) in the previous unit cycle are added According to the result, the rotor angle at the current unit period? T (?

_r ).

_r)가 구해질 수 있다. 이와 관련된 내용은 이하에서 상세히 설명될 것이다. That is, the subtraction result and the addition result are substituted into the relational expression of voltage and current due to the inductance of the AC electric motor 11, and the rotor angle (

_r ) can be obtained. The related contents will be described in detail below.

Accordingly, since the rotor position can be internally detected without using an additional rotor-position sensing device such as a resolver, the size and manufacturing cost of the drive devices 12 and 13 of the AC electric motor 11 are reduced .

When the three-phase AC voltage is applied to the stator of the AC electric motor 11, the rotor of the AC electric motor 11 rotates. The driving unit 13 includes a driving voltage converting unit 131 and a pulse width modulator (PWM) 132.

The driving voltage converter 131 converts the applied voltages V ^s _dqs , which are the d ^s -axis voltage V ^s _ds and the q ^s -axis voltage V ^s _qs from the controller 12, into three- .

The pulse width modulating unit 132 applies the three-phase alternating voltage from the driving voltage converting unit 131 to the stator of the alternating-current electric motor 11 by pulse width modulation.

The driving control unit 12 includes a first feedback current conversion unit 1211, a second feedback current conversion unit 1212, a first current subtraction unit 1213, a proportional-integral control unit 1214, a forward control voltage generation unit 1215 A first voltage addition unit 1216, a control voltage conversion unit 1217, an injection voltage generation unit 1218, and a second voltage addition unit 1219.

The first of d ^S in the feedback current converter 1211 is an AC Motor 11 is a three-phase coordinate system (abcs) three-phase drive is detected by the stationary coordinate (dqs) a current in flows in the stator of a-axis and the q ^S - Axis drive current values (i ^S _dqs ).

_r)에 따라, 제1 귀환 전류 변환부(1211)로부터의 정지 좌표계(dqs)에서의 d^S-축 및 q^S-축 구동 전류 값들(i^S _dqs)을 동기 좌표계에서의 d^S-축 및 q^S-축 구동 전류 값들(i^r _dqs)로 변환한다.The second feedback current conversion section 1212 converts the rotor angle detected by the rotor position detection section 122

axis and the q ^S --axis of the d ^S in the drive current values (i ^S _dqs) a synchronous coordinate system axis and _r), the first of d ^S in the still coordinate system (dqs) from the return current converter 1211 according to the q ^S -axis drive current values (i ^r _dqs ).

Claim of d ^S in the first current subtraction section 1213 synchronous coordinate system (dqr) axis and the q ^S-axis target current values (i ^{r *} _dqs) and a second of d ^S from the return current converter 1212-axis And q ^S -axis driving current values (i ^r _dqs ).

The proportional-integral control unit 1214 performs proportional-integral control on the error current values from the first subtractor 1213 to calculate d ^s -axis and q ^s -axis feedback control voltage values V (dqr) in the synchronous coordinate system dqr ^r _dqsfb .

Forward control voltage generation section 1215 ^S d in synchronization with the coordinate system (dqr) consistent with the intrinsic properties of the alternating current motor (11) generates an axial forward control voltage values (V ^r _dqsff) - ^S-axis and q.

A first voltage adder section 1216 is proportional to - d ^S from the integration control 1214-axis and the q ^S - from the axis feedback control voltage values (V ^r _dqsfb) and a forward control voltage generating section (1215) d ^S - ^S-axis and the q - axis forward control voltage values (V ^r _dqsff) of the added result ^S d - ^S-axis and the q - axis control voltage values (V ^r _dqsf) is generated.

_r)에 따라, 제1 전압 가산부(1216)로부터의 동기 좌표계(dqr)에서의 d^S-축 및 q^S-축 제어 전압 값들(V^r _dqsf)을 정지 좌표계(dqs)에서의 d^S-축 및 q^S-축 제어 전압 값들(V^S _dqsf)로 변환시킨다.The control voltage converter 1217 converts the input angle of the rotor (

according to _r), the first voltage d ^S in the synchronous coordinate system (dqr) from the addition unit 1216-axis and the q ^S-in axis control voltage values (V ^r _dqsf) a stationary coordinate (dqs) d ^S - Axis and q ^S -axis control voltage values (V ^S _dqsf ).

The axial injection voltage (V ^S _dqsh) - injections voltage for electronic position detection generating unit 1218 controls the injection period the above (a Tci 3) polar combination of different four pairs in d ^S - axis and q ^S Are sequentially generated.

Here, the control injection frequency, which is an inverse number of the control injection period (Tci in Fig. 3), is 1/2 of the switching frequency of the pulse width modulation unit 132. [

For example, when the switching frequency of the pulse width modulation section 132 is 5 kilohertz (KHz) and the proportional-integral control section 1214 performs double sampling, the sampling frequency of the proportional-integral control section 1214 is 10 kHz and the control injection frequency is 2.5 kHz (see Figures 3 and 4).

As such a relatively low control injection frequency is used, there is a further effect that the response performance of the proportional-integral controller 1214 can be further improved.

Second voltage addition unit 1219 d ^S in the still coordinate system (dqs) from the control voltage converting unit 1217-axis and the q ^S-axis control voltage values (V ^S _dqsf) and injection voltage generation section 1215 in a still coordinate system (dqs) from d ^s - axis and q ^s - axial injection voltage values (V ^s _dqsh) the driving voltage conversion unit in said applied voltage of the addition result (V ^s _dqs) a drive (13) (131).

Axis and the q ^S - - axial injection voltage (V ^S _dqsh1) in the control injection period (Tci in Fig. 3), the first 1 d ^S in one unit period (sampling period of 3 △ T, t ₀ to t ₁₎ is applied and the second unit period (t ₁ to t ₂₎ the second d ^S in the - in the axial injection voltage (V ^S _dqsh2) is applied, the third unit period (t ₂ to t _3)-axis and q ^S claim 3 d ^S - axis and q ^S - axial injection a voltage (V ^S _dqsh3) is applied, a fourth a fourth unit period (t ₃ to t ₄₎ d ^S - axis and q ^S - axial injection voltage (V ^S _dqsh4 ) is applied.

Hereinafter, the operation principle of the rotor position detection unit 122 of FIG. 1 will be described with reference to the equations.

Generally, the voltage equations of the stationary coordinate system of the three-phase AC electric motor 11 are expressed by the following equation (1).

In the above Equation 1 v ^S _ds is d ^S - the axis control voltage values, v ^S _qs is q ^S - to the axis control voltage value, R _S is the stator resistance, i ^S _ds is d ^S - axis stator current a, i ^S _qs is q ^S - axis stator current value, λ ^S _ds is d ^S - an axial magnetic flux value, λ ^S _qs is q ^S - an axial magnetic flux value, L _S is the inductance matrix, λ _f is a primary a magnetic flux value, θ _r is e times the angle, L _ds is d ^S - axis inductance, and L is _qs q ^S - refers to the axis inductance, respectively.

Therefore, a relational expression of voltage and current due to inductance can be derived as shown in Equation (2) below.

In the above equation (2), ω _r denotes a rotor angular velocity, v ^S _dqs denotes a d ^S -axis or q ^S -axis control voltage value, i ^S _dqs denotes a d ^S -axis or q ^{S- S} _ds is d ^S - a-axis current value, ^S i is _qs q ^S - refers to a-axis current value, respectively.

Here, the d ^S in the still coordinate system (dqs) from the injection voltage generation unit 1215-axis and the q ^S-axis injection voltage frequency of (V ^S _dqsh) is still coordinate system from the control voltage conversion section 1217 significantly higher than the frequency of the axis control voltage (V ^s _dqsf) - ^s-axis and the q - d ^s in (dqs).

That is, in the above to remove all anti except for the second term on the right hand side of equation (2), rotating coordinates (dqs) d ^S - axis or q ^S - axis value of the injected voltage (V ^S _dqsh) and the injection current value (i ^S _dqsh ). Therefore, by substituting (L _S ) for the inductance matrix of the above equation (1) into this relation, the following equation (3) can be derived.

When the above formula (3) is summarized with respect to the injection current value (i ^S _dqsh ), the following equation (4) is established.

On the other hand, in the case of this embodiment, d ^S - axial injection voltage (V ^S _dsh) q ^S sine (sine) functions is with respect to the time (t) - the axis injection voltage (V ^S _qsh) is a cosine with respect to time (t) (sine) function. That is, the injection voltage generation unit of d ^S in the still coordinate system (dqs) from a 1215-can the be obtained by the equation (5) under axial injection voltage values (V ^S _dqsh) (3-axis and the q ^S And 4).

In Equation 5 V _inj is ^S d - axis or q ^S - is the size of the injection axis voltage (V ^S _dqsh), ω _h is an angular velocity of the injected voltage (V ^S _dqsh).

In this case, Substituting Equation (5) to Equation (4), the rotor angle cosine component of (cos 2θ _r) of twice (cos 2θ _r) from the d ^S - axis to obtain the injection current (i ^S _dsh) , And the q ^S -axis injection current (i ^S _qsh ) can be obtained from the sinusoidal component (sin 2θ _r ) of the rotor angle (cos 2θ _r ) at two times. That is, the following equation (6) can be derived.

Here, the controlled injection period (Tci in Fig. 3) includes a first unit period (Fig. 3 of t ₀ to t _1), the second unit period (t ₁ to t _2), the third unit period (t ₂ to t ₃ ), And a fourth unit period (t ₃ to t ₄ ). The voltage injection point in the first unit period (t ₀ to t _{1 in} FIG. 3) is t ₀ , the voltage injection point in the second unit period (t ₁ to t ₂ ) is t ₁ , and the third unit period t ₂ to t ₃ is t _2, and the voltage injection time at the fourth unit period (t ₃ to t ₄ ) is t ₃ .

Therefore, when the result (ω _h t) obtained by multiplying the angular speed (ω _h ) of the injection voltage (V ^s _dqsh ) by the time t is 0 in the above Equation (6) t ₀ to t ₁ ). When the result (ω _h t) obtained by multiplying the angular speed ω _h of the injection voltage (V ^s _dqsh ) by the time t is π / 2 corresponds to the second unit period (t ₁ to t _{2 in} FIG. 3) do. When the result (ω _h t) obtained by multiplying the angular velocity ω _h of the injection voltage (V ^s _dqsh ) by the time t corresponds to the third unit period (t ₂ to t ₃ in FIG. ₃ ). Then, when the result (ω _h t) of the angular velocity ω _h of the injection voltage (V ^s _dqsh ) multiplied by the time t is 3π / 2 corresponds to the fourth unit period (t ₃ to t _{4 in} FIG. 3) do.

Thus, by as substituted for the details on the equation 6, d ^S in each unit period of the - to derive the formula to calculate the axial injection current (i ^S _qsh)-axis injection current (i ^S _dsh) and q ^S .

Thus, the first unit period (Fig. 3 of t ₀ to t ₁₎ of d ^S in-axis injection current (i ^S _dsh1) and q ^S-axis injection current (i ^S _qsh1) equation of equations below for calculating a 7 Can be expressed as:

In addition, the second unit period (Fig. 3 of t ₁ to t ₂₎ of d ^S in-axis injection current (i ^S _dsh2) and q ^S-axis equation Equation 8 below for calculating the injection current (i ^S _qsh2) Can be expressed as:

In addition, the third unit period (Fig. 3 of t ₂ to t ₃₎ of d ^S in-axis injection current (i ^S _dsh3) and q ^S-axis expression equation below 9 for calculating the injection current (i ^S _qsh3) Can be expressed as

And a fourth unit period (Fig. 3 of t ₃ to t ₄₎ of d ^S in-axis injection current (i ^S _dsh4) and q ^S-axis expression equation (10) below to calculate the injection current (i ^S _qsh4) Can be expressed as:

Using Equations (7) to (10), subtraction equations and addition equations can be commonly set between the previous unit period and the current unit period. Further, a cosine component of the rotor angle (2θ _r) of 2 times by as substituting the value of the measured injection current to the subtraction equations and adding equation (cos 2θ _r) and sine component (sin 2θ _r) can be obtained and, a cosine component (cos 2θ _r) and sine component (sin 2θ _r) from the rotor angle (θ _r) of the current unit period is determined may be obtained.

Between the previous unit cycle and the current unit cycle, the subtraction equation and the addition equation can be set as shown in Equation (11) below.

To summarize the equation (11), to calculate for each of the unit cycle, times the cosine component of the electronic angle (2θ _r) of twice (cos 2θ _r) and sine component (sin 2θ _r), the following two operations Are performed first.

First, q ^S at the current unit of cycle-axis value of the injection current _{^{(i S qsh (j + 1}} )) at d ^S in the previous unit period - the value of the axial injection current (i ^S _dsh (j)) is subtracted , the subtraction result ^S d-axis injection polarity (+ or -) of the voltage value of the subtraction result data (Dat1) haejyeoseo the product is generated.

Second, q ^S in the previous unit period - and adding the value of the axial injection current _{^{(i S dsh (j + 1}} )) - axis value of the injection current (i ^S _qsh (j)) and d ^S of the current unit period , The addition result is multiplied by the polarity (+ or -) of the q ^S -axis injection voltage value, and the addition result data Dat2 is generated

The polarity sign (V ^S _dsh ) of the d ^S -axis injection voltage value, the polarity sign (V ^S _qsh ) of the q ^S -axis injection voltage value, and the sine component (sin 2? _R ) And cosine components (cos 2? _R ) are summarized in the following Table 1.

  The first unit cycle   The second unit cycle   Third unit cycle   The fourth unit cycle sign (V ^S _dsh ) - -         +         + sign (V ^S _qsh )        +         -         -         + sin 2? _r i ^S _qsh1 + i ^S _dsh2 (Added) i ^S _dsh2 - i ^S _qsh3 (Subtraction) -i ^S _qsh3 - i ^S _dsh4 (Added) -i ^S _dsh4 + i ^S _qsh1 (Subtraction) cos 2? _r i ^S _dsh1 - i ^S _qsh2 (Subtraction) -i ^S _qsh2 - i ^S _dsh3 (Added) -i ^S _dsh3 + i ^S _qsh4 (Subtraction) i ^S _qsh4 + i ^S _dsh1 (Added)

Thus, the current in each of the unit cycle, the double rotor angle cosine component of the _{(2θ r) (cos 2θ r} ) and sine component (sin 2θ _r) is obtained, by the arc tangent (tan ^-1) operation The rotor angle? _R in the unit period can be obtained.

Therefore, since the rotor position can be internally detected without using an additional rotor-position sensing device such as a resolver, the size and manufacturing cost of the drive device of the AC motor can be reduced.

5 shows the internal structure of the rotor position detector 122 of FIG.

1 and 5, the rotor position detection unit 122 includes a signal processing unit 51, a rotor angle calculation unit 52, and a filter unit 53.

Signal processor 51, a 1 d ^S from the return current converter 1211-axis and the q ^S-axis drive currents (i ^S _dqs), and d ^S from the injection voltage generation unit 1218-axis And q ^S -axis injection voltages (V ^s _dqsh ) and subtracting the value of the d ^s -axis injection current in the previous unit cycle from the value of q ^s -axis injection current in the current unit period (Dat1), and d ^S at the current unit of cycle-axis and outputs a result of the data obtained by adding the value of the injection current (Dat2) at the same time - q ^S in the previous unit period from the value of the axial injection current.

_rCal)를 구한다.The rotor angle calculation section 52 substitutes the subtraction result data Dat1 and the addition result data Dat2 from the signal processing section 51 into the subtraction and addition equation of the expression (11) a sine (sine) component and a cosine (cosine) to obtain the composition, the obtained times twice the current unit period in accordance with a sign of the electron angle (sine) component (sin 2θ _r) and a cosine (cosine) component (cos 2θ _r) Of the rotor angle (2

_rCal ).

_rCal)의 신호의 노이즈 성분을 제거하면서 회전자 각도(

_r)를 최종적으로 구하고, 최종적으로 구해진 회전자 각도(

_r)를 구동 제어부(121) 내의 제2 귀환전류 변환부(1212) 및 제어 전압 변환부(1217)에 각각 제공한다.The filter section 53 has a rotor angle of twice as large as the rotor angle from the rotor angle calculator 52

_rCal ) while removing the noise component of the signal of the rotor

_r ) is finally obtained, and the finally obtained rotor angle (

_r to the second feedback current converter 1212 and the control voltage converter 1217 in the drive controller 121, respectively.

Fig. 6 shows the internal configuration of the signal processing unit 51 of Fig.

1, 6 and Table 1, the signal processing unit 51 included in the rotor position detection unit 122 includes a first unit period delay unit 601, a polarity discrimination unit 602, a band pass filter A second current subtractor 605, a current adder 606, a first multiplier 607, and a second multiplier 608. The second multiplier 608 multiplies the output of the second multiplier 608 by the second multiplier 608,

A first unit period delay unit 601, d ^S from the injection voltage generation unit 1218-axis and the q ^S-axis injection voltage values (V ^S _dqsh) to by as a unit by delaying period output current unit It generates an injection axis voltage values (V ^S _dqsh) - in the period d ^S - ^S-axis and q.

Polarity determination unit 602, the first in the current unit of period from a unit period delay unit (601) d ^S - axis and q ^S - axis receives the injection voltage values (V ^S _dqsh), in the current unit of cycle d ^S - Generates the polarity signal (Sig D) of the axis injection voltage value and the polarity signal (Sig Q) of the q ^S - axis injection voltage value.

A band-pass filter 603, a first feedback from the current converter (1211) d ^S - axis and q ^S - axis drive currents at the period the current unit by performing a band filter with respect to (i ^S _dqs) It generates an-axis value of an injection current _{^{(i S qsh (j + 1}} )) - d S - axis value of an injection current _{^{(i S dsh (j + 1}} )) , and ^S q.

A second unit period delay unit 604, d ^S of the current unit period from the band-pass filter 603 - the value of the axial injection current (i ^S _dsh (j + 1)) and the q ^S-axis of the injection current value by as _{^{(i S qsh (j + 1}} )) a unit delays by period outputs a, d ^S of the current unit cycle - the value of the axial injection current _{^{(i S dsh (j + 1}} )) and the q ^S-axis the value of the axial injection current (i ^S _dsh (j)) and a q ^S - - the value of the injection current _{^{(i S qsh (j + 1}} )) before d ^S in the unit period to the axis values of the injection current (i ^S _qsh (j).

The second current subtractor 605 subtracts the value of the q ^S -axis injection current (i ^S _qsh (j + 1)) in the current unit period from the band pass filter 603 from the second unit period delay unit 604 (I ^S _dsh (j)) of the d ^s -axis injection current in the previous unit cycle from the output of the subtracter ₂₂ , and outputs the value of the subtraction result.

The current adding unit 606 adds the value of the q ^S -axis injection current (i ^S _qsh (j)) in the previous unit period from the second unit period delay unit 604 and the current unit cycle d ^S in - adding the value of the axial injection current _{^{(i S dsh (j + 1}} )) , and outputs the value of the addition result.

The first multiplier 607, a second d ^S from the subtraction result and an edge determination unit 602 from the current subtraction unit (605) receives the shaft polarity signal (Sig D) of the injection voltage, the second subtracting the result from the current subtraction unit (605) d ^S - multiplying the polar axis of the injection voltage to generate the data (Dat1) of the subtraction result.

The second multiplier 608 receives the addition result from the current addition unit 606 and the polarity signal Sig Q of the q ^S -axis injection voltage value from the polarity determination unit 602, 606 by the polarity of the q ^S -axis injection voltage value to generate the data (Dat 1) of the addition result.

As described above, according to embodiments of the present invention, controlled by the injection period, the polarity of each other in combination with other four pairs of ^S d - ^S-axis and the q - axis injection voltage are applied sequentially.

Further, the control implant in the period, the current unit period q ^S-axis d ^S of the previous unit period from the value of the injection current - the value of the axial injection current subtraction result, and the present unit period d ^S-value in the axial injection current And the value of q ^S - axis injection current in the previous unit cycle are added, the rotor angle in the present unit cycle can be obtained.

That is, the rotor angle in the current unit cycle can be obtained by substituting the subtraction result and the addition result into the relational expression of the voltage and current by the inductance of the AC motor.

Therefore, since the rotor position can be internally detected without using an additional rotor-position sensing device such as a resolver, the size and manufacturing cost of the drive device of the AC motor can be reduced.

The present invention has been described above with reference to preferred embodiments. It will be understood by those skilled in the art that the present invention may be embodied in various other forms without departing from the spirit or essential characteristics thereof. Therefore, the above-described embodiments should be considered in a descriptive sense rather than a restrictive sense. The scope of the present invention is defined by the appended claims rather than by the foregoing description, and the inventions claimed by the claims and the inventions equivalent to the claimed invention are to be construed as being included in the present invention.

There is a possibility of being used in a DC motor other than an AC motor.

11: AC motor, 12: control part,
13: driving unit, 121: driving control unit,
122: rotor position detection unit, 131: drive voltage conversion unit
132: pulse width modulation unit, 1211: first feedback current conversion unit,
1212: second feedback current conversion section, 1213: first current subtraction section,
1214; A proportional-integral control unit, 1215: a forward control voltage generating unit,
1216: first voltage adding unit, 1217: control voltage converting unit,
1218: an injection voltage generating unit, 1219: a second voltage adding unit,
51: signal processing section, 52: rotor angle calculating section,
53: filter unit, 601: first unit-cycle delay unit,
602: Polarity discrimination unit, 603: Band-pass filter,
604: second unit period delay unit, 605: second current subtractor,
606: current addition unit, 607: first multiplier unit,
608: second multiplication unit.

Claims (11)

delete A method of driving an alternating-current motor in which the alternating-current motor is driven while periodically determining a rotor angle of the alternating-current motor,
q ^S voltage for the rotational force generated in the axial voltage and the still coordinate system - - (a) rotating coordinates exciting current voltage of d ^S for in by the shaft voltage, but driving the alternating current motor, controlled injection cycle polarity combination is different from four pairs of ^S d - ^S-axis and the q - the method comprising applying axial injection voltage in sequence;
(b) in the control injection cycle, q ^S of the current unit of cycle - a result of subtracting the value of the axial injection current, and the current unit period d ^S - - d ^S of the previous unit period in the axis value of the injection current axial injection current the value of ^S and q in the previous unit period - according to the result of adding the value of the axial injection current, and a step to obtain a rotor angle in the current unit period,
In the step (a) and the step (b)
Four unit periods are set by dividing the control injection period by four,
To the stator, by As-axis injection voltage are injected sequentially-axis injection current and d ^S--axis injection current is four pairs of d ^S in the four-unit period-axis and the q ^S q ^S at each of the four unit periods And a current flowing in addition to the AC motor. delete delete delete An AC motor drive apparatus for driving an AC motor while periodically determining a rotor angle of the AC motor,
A control unit; And
And a driving unit for driving the AC electric motor in accordance with an applied voltage from the control unit,
The control unit,
Q ^S voltage for the rotational force generated in the axial voltage and the stationary coordinate-exciting current voltage of d ^S for in-rotating coordinates by the shaft voltage, but driving the alternating current motor, controlled injection cycle polarity combination with each other pair of the other four in ^S d - ^S-axis and the q - drive control unit for applying the axial injection voltage in sequence; And
In the control injection cycle, the current unit of cycle q ^S of - a result of subtracting the value of the axial injection current, and the current unit period d ^S - - axis d ^S of the previous unit period from the value of the injection current value of the axial injection current and And a rotor position detector for obtaining a rotor angle in a current unit cycle according to a result of adding the value of q ^S - axis injection current in the previous unit cycle,
Four unit periods are set by dividing the control injection period by four,
To the stator, by As-axis injection voltage are injected sequentially-axis injection current and d ^S--axis injection current is four pairs of d ^S in the four-unit period-axis and the q ^S q ^S at each of the four unit periods The drive of the alternating current motor, which is additionally shedding currents. delete delete delete delete delete

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