JP3627426B2 - Control device for rotating electrical machine - Google Patents

Description

【００２１】
またトルクは前述の式（１）で表わされる。トルクの式（１）において、温度変化により永久磁石による鎖交磁束λが変化するとトルクＴが変化するが、変化後の鎖交磁束λを推定して電流指令値を計算することにより、トルク指令に対して正確に一致するトルク制御が可能となる。
【００２２】
図６に示す制御装置において磁化電流指令Ｉ_ｄ ^＊ は、図４に示す制御装置と同様に、最大トルク制御、弱め界磁による定出力制御を行なうべく電気角周波数ωをパラメータとしてトルク指令Ｔ^＊ に基づき磁化電流指令テーブル１３より導出する。すなわち、この磁化電流指令テーブル１３はトルク指令Ｔ^＊ 及び電気角周波数ωにより一意に決定される磁化電流指令Ｉ_ｄ ^＊ をテーブルとして記憶している。
【００２３】
かくしてトルク指令Ｔ^＊ 、磁化電流指令Ｉ_ｄ ^＊ 及び電気角周波数ωが決定され、鎖交磁束λの推定値である磁束推定値λ^＊＊が与えられると式（２）を変形して次式（３）によりトルク電流指令Ｉ_ｑ ^＊ が求められる。
【００２４】
【数２】

【００２５】
トルク電流指令演算部１４はトルク指令Ｔ^＊ 、磁化電流指令Ｉ_ｄ ^＊ 及び磁束推定器１５で推定する磁束推定値λ^＊＊に基づき上式（３）の演算を行ってトルク電流指令Ｉ_ｑ ^＊ を出力する。この結果得られた磁化電流指令Ｉ_ｄ ^＊ 及びトルク電流指令Ｉ_ｑ ^＊ が電流制御部８に供給される。
【００２６】
ここで、磁束推定値λ^＊＊は次の原理により求める。すなわち、式（２）において、鎖交磁束λはトルク電圧Ｖ_ｑ の式にのみ影響する。ここで、Ｒ_１ ，Ｌ_ｄ はモータパラメータとして既知であるため、トルク電圧推定値Ｖ_ｑ ^＊＊は磁束推定値λ^＊＊を用いた次式（４）で表される。
Ｖ_ｑ ^＊＊＝Ｒ_１Ｉ_ｑ ＋ωＬ_ｄＩ_ｄ ＋ωλ^＊＊ ……（４）
（λ^＊＊＝λ_ｎ ＋Δλ^＊＊）
λ_ｎ ：磁束の初期設定値（基準温度において測定した磁束）
Δλ^＊＊：磁束変化量の推定値
【００２７】
図６の電流制御系８においては、磁化電流指令Ｉ_ｄ ^＊ ，トルク電流指令Ｉ_ｑ ^＊ が実際の磁化電流検出値Ｉ_ｄ， トルク電流検出値Ｉ_ｑ に一致する様にフィードバック制御しているため、温度変化により鎖交磁束λが変化した場合には、磁化電流指令Ｉ_ｄ ^＊ ， トルク電流指令Ｉ_ｑ ^＊ の電流を流すために必要なトルク電圧指令Ｖ_ｑ ^＊ と式（４）により求められるトルク電圧推定値Ｖ_ｑ ^＊＊に偏差が生ずる。この電圧偏差は磁束変化量の推定値Δλ^＊＊に対応しているため、この磁束変化量の推定値Δλ^＊＊は次式（５）により求めることができる。
Δλ^＊＊＝Ｇ・（Ｖ_ｑ ^＊ −Ｖ_ｑ ^＊＊） ……（５）
Ｇ：伝達関数
【００２８】
式（５）より磁束推定値λ^＊＊は、次式（６）で求められる。
λ^＊＊＝λ_ｎ ＋Ｇ（Ｖ_ｑ ^＊ −Ｖ_ｑ ^＊＊） ……（６）
式（６）における（Ｖ_ｑ ^＊ −Ｖ_ｑ ^＊＊）の偏差が０となる様にλ^＊＊を推定する。 この結果（Ｖ_ｑ ^＊ −Ｖ_ｑ ^＊＊）が０となると、実際のＰＭモータ２における鎖交磁束λと磁束推定値λ^＊＊とが一致する。
【００２９】
ここで電流制御系８の出力であるトルク電圧指令Ｖ_ｑ ^＊ は、図６より次式（７）で与えられる。
【００３０】
【数３】

【００３１】
【数４】

【００３２】
したがって磁束の推定は、式（４）の演算を行わなくても、換言すれば図６に示す磁束推定器１５を用いなくてもｑ軸のＩＰ制御部１０の出力Ｖ_ＩＰを式（５）の（Ｖ_ｑ ^＊ −Ｖ_ｑ ^＊＊）に代入することで可能となる。すなわち式（５）より、
λ^＊＊＝λ_ｎ ＋Ｇ・Ｖ_ＩＰ ……（９）
となる。
【００３３】
式（９）における伝達関数ＧとしてはＫ_Ｐ （比例ゲイン）、Ｋ_ｉ ／Ｓ（積分ゲイン）、（Ｋ_Ｐ ／１＋ＳＴ）（一次遅れ）、（Ｋ_Ｐ ＋Ｋ_ｉ ／Ｓ）（比例・積分ゲイン）等が考えられる。
【００３４】
上述の如き知見に基づく本発明の第１の実施の形態に係るブロック線図を図１に示す。同図に示すように、本形態に係る磁束推定器１６はＩＰ制御部１０の出力Ｖ_ＩＰに所定の伝達関数Ｇを掛けることにより磁束推定値λ^＊＊を演算するように構成してある。この演算結果である磁束推定値λ^＊＊は、トルク電流指令演算部１４及び式（２）の鎖交磁束λを補正すべくトルク電圧供給部１７にそれぞれ供給される。他の構成は図６と同じであるため同一部分には同一番号を付し重複する説明は省略する。
【００３５】
かかる本形態によれば磁束推定器１６において式（９）の演算を行うことにより磁束推定値λ^＊＊を求める。トルク電流指令演算部１４では磁束推定値λ^＊＊に基づき式（３）の演算を行うことによりトルク電流指令Ｉ_ｑ ^＊ を求め、これを電流制御部８に供給する。このトルク電流指令Ｉ_ｑ ^＊ は現実の永久磁石の鎖交磁束をλを反映してトルク指令Ｔ^＊ に正確に対応した指令とすることができる。
【００３６】
なお、図１においてＩＰ制御部１０をＰＩ制御部として構成しても良い。
【００３７】
図１に示す制御装置では理想状態を考えたが、実際にはＩＰ制御部１０の出力Ｖ_ＩＰには、出力電流による電力変換素子（ＩＧＢＴ等）の電圧降下分を補正する成分が含まれることになる。
【００３８】
ここで、ｄ軸に電流を流さないＩ_ｄ ＝０制御では、電力変換素子の電圧降下分はｑ軸電圧Ｖ_ｑ のみに現れるため、ｄ−ｑ座標上の直流量にて補正が可能となる。すなわち、基準温度において、磁束の補償を行なわずに（磁束は初期設定値とする）トルク指令Ｔ^＊ （トルク電流指令Ｉ_ｑ ^＊ ）を変化させ、その時のＩＰ制御部１０の出力Ｖ_ＩＰを測定すれば、トルク指令Ｔ^＊ に対する電力変換素子の電圧降下分に基づく電圧降下補正分Ｖ_ｘ が分かる。したがって、この測定データをテーブル化しておき、式（７）に加算することで、ＩＰ制御部１０の出力Ｖ_ＩＰはトルク電圧指令Ｖ_ｑ ^＊ とトルク電圧推定値Ｖ_ｑ ^＊＊の偏差分をより正確に反映したものとなる。
【００３９】
【数５】

【００４０】
上述の如き知見に基づく本発明の第２の実施の形態に係るブロック線図を図２に示す。同図に示すように、本形態に係るＶ_ｘ テーブル１８にはトルク指令Ｔ^＊ に対応する電圧降下補正分Ｖ_ｘ を記憶してあり、トルク指令Ｔ^＊ に応じた電圧降下補正分Ｖ_ｘ を出力して出力Ｖ_ＩＰに加算するように構成してある。他の構成は図１と同じであるため同一部分には同一番号を付し重複する説明は省略する。
【００４１】
かかる本形態によれば、Ｉ_ｄ ＝０制御において精度よく磁束の推定ができ、トルク制御精度も向上する。
【００４２】
さらに、電力変換素子のスイッチング時間の影響により、デットタイムを設ける必要があり、このためトルク電圧指令Ｖ_ｑ ^＊ と実際の出力電圧とに誤差が生じてくる。これは、電気角周波数に依存して変化する。したがって、図２に示す制御装置の電圧降下補正分Ｖ_ｘ もＩＰ制御部１０の出力Ｖ_ＩＰに含まれてくることになる。
【００４３】
ここで第２の実施の形態と同様に、トルク指令Ｔ^＊ のみならず電気角周波数ωに対してＩＰ制御部１０の出力Ｖ_ＩＰを測定し、トルク指令Ｔ^＊ 及び電気角周波数ωに対する３次元のテーブルを形成し、このテーブルに基づく電圧降下補正分Ｖ_ｘ を式（１０）に代入すればＩＰ制御部１０の出力Ｖ_ＩＰはトルク電圧指令Ｖ_ｑ ^＊ とトルク電圧推定値Ｖ_ｑ ^＊＊との偏差分となる。そして、このときの電圧降下補正分Ｖ_ｘ は電力変換素子の電圧降下分とデットタイムの影響による補正分を表わすことになる。
【００４４】
上述の如き知見に基づく本発明の第３の実施の形態に係るブロック線図を図３に示す。同図に示すように、本形態に係るＶ_ｘ テーブル１８にはトルク指令Ｔ^＊ 及び電気角周波数ωに対応する電圧降下補正分Ｖ_ｘ を記憶してあり、トルク指令Ｔ^＊ 及び電気角周波数ωに応じた電圧降下補正分Ｖ_ｘ を出力して出力Ｖ_ＩＰに加算するように構成してある。他の構成は図１と同じであるため同一部分には同一番号を付し重複する説明は省略する。
【００４５】
かかる本形態によれば、Ｉ_ｄ ＝０制御において精度よく磁束の推定ができ、トルク制御精度も向上する。このとき第２の実施の形態よりも磁束推定及びトルク制御の精度がさらに向上する。
【００４６】
【発明の効果】
以上実施の形態とともに詳細に説明したように、本発明によれば磁束推定手段はトルク電流指令系の出力を用いているので、永久磁石の温度による減磁分を補償して指令値に対応する正確な制御を実現することができるばかりでなく、磁束推定のための演算時間も短縮することができる。さらに、Ｉ_ｄ ＝０制御においてトルク電流指令の制御部に電力変換素子の電圧降下、又は電圧降下とデッドタイムの影響とによる補正分を予め加算しておくことにより磁束推定及びトルク制御精度をさらに改善することができる。
【図面の簡単な説明】
【図１】本発明の第１の実施の形態を示すブロック線図。
【図２】本発明の第２の実施の形態を示すブロック線図。
【図３】本発明の第３の実施の形態を示すブロック線図。
【図４】従来技術に係る制御装置を示すブロック線図。
【図５】永久磁石の温度特性を示す特性図。
【図６】磁束推定の原理を説明するための制御装置を示すブロック線図。
【符号の説明】
２ ＰＭモータ
１０ ＩＰ制御部
１３ 磁化電流指令テーブル
１４ トルク電流指令演算部
１６ 磁束推定器
１７ トルク電圧供給部
１８ Ｖ_ｘ テーブル
λ^＊＊ 磁束推定値
Ｔ^＊ トルク指令
Ｉ_ｄ ^＊ 磁化電流指令
Ｉ_ｑ ^＊ トルク電流指令
Ｖ_ｄ ^＊ 磁化電圧指令
Ｖ_ｑ ^＊ トルク電圧指令
ω 電気角周波数
Ｖ_ｑ ^＊＊ トルク電圧推定値
Ｖ_ＩＰ 出力
Ｖ_ｘ 電圧降下補正分[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a control device for a rotating electrical machine, and is particularly useful when applied to an apparatus having a permanent magnet as a field.
[0002]
[Prior art]
Permanent magnet synchronous motors (hereinafter abbreviated as “PM motors”) driven by inverters are widely used mainly as small-capacity AC servomotors.
[0003]
FIG. 4 is a block diagram showing an example of this type of PM motor control device together with this PM motor. As shown in the figure, the PM motor 2 is rotated by a three-phase current supplied by the PWM inverter 1. The speed detector 3 rotates with the rotor of the PM motor 2 and outputs a pulse signal P. Based on the pulse signal P, the position detection unit 4 detects a phase detection value θ indicating the rotor position (phase) of the PM motor 2.
[0004]
The current detection units 5 and 6 obtain U-phase and W-phase current detection values I _U and I _w . Coordinate converter 7 current detection value _I U, obtains a current detection value _{I v} of the V-phase from the _{I w,} further converts the three-phase current detection value _{I U, I v,} the three-phase / two-phase of _{I w,} the phase The magnetizing current detection value _Id and the torque current detection value _Iq of the rotating coordinate system are obtained in consideration of the detection value θ.
[0005]
The current control unit 8 rotates by performing a proportional / integral calculation on a deviation between the magnetizing current command I _d ^* and the torque current command I _q ^* in the rotating coordinate system and the magnetizing current detection value I _d and the torque current detection value I _q. A magnetization voltage command V _d ^* and a torque voltage command V _q ^* in the coordinate system are obtained.
[0006]
Here, the magnetizing current command I _d ^* and the torque current command I _q ^* are obtained from the current command table 11 based on the torque command T ^* . That is, the current command table 11 stores the magnetizing current command I _d ^* and the torque current command I _q ^* corresponding to the torque command T ^* as a table. In addition, an electrical angular frequency ω obtained by differentiating the phase detection value θ by the differentiator 12 is supplied to the current command table 11 as a reference signal. Thus, the current command table 11 sends out the magnetizing current command I _d ^* and the torque current command I _q ^* which are uniquely determined with reference to the electrical angular frequency ω based on the torque command T ^* .
[0007]
The coordinate conversion unit 9 converts the magnetization voltage command V _d ^* and the torque voltage command V _q ^* in the rotating coordinate system and converts the three-phase voltage commands V _U ^* , V _v ^* , and V _w ^* in the stationary coordinate system. Ask.
[0008]
The PWM inverter 1 controls the inverter unit based on the voltage commands V _U ^* , V _v ^* , and V _w ^* in the PWM modulation unit incorporated therein. As a result, three-phase power is supplied from the PWM inverter 1 to the PM motor 2.
[0009]
As a control method of the PM motor 2 using such a control device, maximum torque control, maximum efficiency control, and the like are known, and when these controls are performed, an electric power representing the torque command T ^* and the rotation speed of the PM motor 2 is known. The magnetizing current command I _d ^* and the torque current command I _q ^* are determined according to the angular frequency ω.
[0010]
The output torque T of the PM motor 2 at this time is represented by the following equation (1).
T = P _n {λI _q + ω (L _d −L _q ) I _d · I _q } (1)
Where P _{n is the number of} pole pairs, λ is the flux linkage caused by a permanent magnet,
ω: electrical angular frequency, L _d : direct-axis inductance,
L _q : horizontal axis inductance, I _d : magnetizing current,
I _q : Torque current
Here, in the prior art, the magnetizing current command I _d ^* and the torque current command I _q ^* are obtained on the assumption that the value of the interlinkage magnetic flux λ in the equation (1) is constant.
[0012]
[Problems to be solved by the invention]
As shown in FIG. 5, the interlinkage magnetic flux λ due to the permanent magnet (Nd—Fe—B magnet) decreases as the temperature of the permanent magnet increases, and the rate of demagnetization increases particularly at higher temperatures. Accordingly, the linkage flux λ decreases and the output torque T decreases as the temperature rises. That is, in the past, demagnetization due to temperature rise was not taken into consideration, so when the motor was operated at a high temperature, the torque T actually output from the PM motor 2 was small with respect to the torque command T ^* .
[0013]
An object of the present invention is to provide a control device for a rotating electrical machine that can obtain an output torque accurately corresponding to a torque command even when the temperature rises.
[0014]
[Means for Solving the Problems]
The configuration of the present invention that solves the above problems is characterized by the following points.
[0015]
1) In a control device for a rotating electrical machine having a permanent magnet as a field,
A magnetizing current command table for outputting a magnetizing current command uniquely determined by a torque command and an electrical angular frequency;
Magnetic flux estimating means for calculating a magnetic flux estimated value that is an estimated value of the linkage flux by the current permanent magnet based on a deviation between the torque current command and the torque current detected value fed back;
Torque current command calculation means for outputting a torque current command by calculation based on a torque command, an electrical angular frequency, and a magnetic flux estimation value.
[0016]
2) In a control device for a rotating electrical machine that has a permanent magnet as a field and performs control to make a magnetization current command zero.
A magnetizing current command table for outputting a magnetizing current command uniquely determined by a torque command and an electrical angular frequency;
Magnetic flux estimating means for calculating a magnetic flux estimated value that is an estimated value of the linkage flux by the current permanent magnet based on a deviation between the torque current command and the torque current detected value fed back;
A torque current command calculating means for outputting a torque current command by a calculation based on the torque command, the electrical angular frequency and the magnetic flux estimated value;
A table of voltage drop by the power conversion element formed in correspondence with the torque command is stored, and compensation means for compensating for the voltage drop by the power conversion element based on this table is provided.
[0017]
3) In a control device for a rotating electrical machine that has a permanent magnet as a field and performs control to make a magnetization current command zero.
A magnetizing current command table for outputting a magnetizing current command uniquely determined by a torque command and an electrical angular frequency;
Magnetic flux estimating means for calculating a magnetic flux estimated value that is an estimated value of the linkage flux by the current permanent magnet based on a deviation between the torque current command and the torque current detected value fed back;
A torque current command calculating means for outputting a torque current command by a calculation based on the torque command, the electrical angular frequency and the magnetic flux estimated value;
A table of voltage drop due to the power conversion element formed corresponding to the torque command and the electrical angular frequency is stored, and compensation means for compensating for the voltage drop due to the power conversion element based on this table is provided. To do.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Each form estimates the current magnetic flux of the permanent magnet as a magnetic flux estimated value λ ^** , and corrects the torque current command I _q ^* using this magnetic flux estimated value λ ^** .
[0019]
Here, the principle of the calculation method of the magnetic flux estimated value λ ^** will be described with reference to FIG. The control device shown in FIG. 6 is obtained by improving a portion for giving a torque current command I _q ^* in the current command table 11 in the control device shown in FIG. Therefore, the same parts as those in FIG.
[0020]
The voltage equation of the PM motor 2 is expressed by the following equation (2) on the synchronous rotation coordinates (dq axes) in a steady state.
[Expression 1]

[0021]
The torque is expressed by the above-described formula (1). In the torque equation (1), the torque T changes when the flux linkage λ by the permanent magnet changes due to a temperature change. However, the torque command is calculated by estimating the linkage flux λ after the change and calculating the current command value. Thus, torque control that exactly coincides with can be performed.
[0022]
In the control device shown in FIG. 6, the magnetizing current command I _d ^* is the torque command T ^{* using the} electrical angular frequency ω as a parameter for maximum torque control and constant output control by field weakening, as in the control device shown in FIG. 4. Based on the magnetization current command table 13. That is, the magnetizing current command table 13 stores the magnetizing current command I _d ^* uniquely determined by the torque command T ^* and the electrical angular frequency ω as a table.
[0023]
Thus, when the torque command T ^* , the magnetizing current command I _d ^*, and the electrical angular frequency ω are determined and the magnetic flux estimated value λ ^** that is the estimated value of the interlinkage magnetic flux λ is given, the equation (2) is transformed to the following equation: The torque current command I _q ^* is obtained from (3).
[0024]
[Expression 2]

[0025]
The torque current command calculation unit 14 performs the calculation of the above formula (3) based on the torque command T ^* , the magnetization current command I _d ^*, and the estimated magnetic flux value λ ^** estimated by the magnetic flux estimator 15 to obtain the torque current command I _q ^*. Is output. The magnetizing current command I _d ^* and torque current command I _q ^* obtained as a result are supplied to the current control unit 8.
[0026]
Here, the estimated magnetic flux value λ ^** is obtained by the following principle. That is, in equation (2), the flux linkage λ only affects expression of a torque voltage V _q. Here, since R ₁ and L _d are known as motor parameters, the torque voltage estimated value V _q ^** is expressed by the following equation (4) using the magnetic flux estimated value λ ^** .
V _q ^** = R ₁ I _q + ωL _d I _d + ωλ ^** (4)
_{^{(Λ ** = λ n + Δλ}} **)
λ _n : Initial setting value of magnetic flux (magnetic flux measured at reference temperature)
Δλ ^** : Estimated value of magnetic flux change amount
In the current control system 8 of FIG. 6, feedback control is performed so that the magnetization current command I _d ^* and the torque current command I _q ^* coincide with the actual magnetization current detection value I _d and the torque current detection value I _q . , if the flux linkage λ by temperature change is changed is determined by the magnetizing current command I _d ^*, the torque current command I _q ^* required torque voltage to flow a current command V _q ^* and the formula (4) Deviations occur in the estimated torque voltage value V _q ^** . The voltage deviation is because it corresponds to the estimated value [Delta] [lambda] ^** of magnetic flux change amount can be determined by the estimated value of the magnetic flux change amount [Delta] [lambda] ^** The following equation (5).
_{^{Δλ ** = G · (V q}} * -V q **) ...... (5)
G: Transfer function [0028]
From formula (5), the estimated magnetic flux value λ ^** is obtained by the following formula (6).
_{^{λ ** = λ n + G (}} V q * -V q **) ...... (6)
Λ ^** is estimated so that the deviation of (V _q ^* −V _q ^** ) in Equation (6) becomes zero. When this result (V _q ^* −V _q ^** ) becomes 0, the flux linkage λ and the estimated magnetic flux value λ ^** in the actual PM motor 2 coincide with each other.
[0029]
Here, the torque voltage command V _q ^* , which is the output of the current control system 8, is given by the following equation (7) from FIG.
[0030]
[Equation 3]

[0031]
[Expression 4]

[0032]
Estimation of flux thus, formula (4) even without operation, in other words the output V _IP expressions IP control unit 10 of the q-axis without using the flux estimator 15 shown in FIG. 6 (5) This can be achieved by substituting (V _q ^* −V _q ^** ). That is, from equation (5),
λ ^** = λ _n + G · V _IP (9)
It becomes.
[0033]
As the transfer function G in the equation (9), K _P (proportional gain), K _i / S (integral gain), (K _P / 1 + ST) (first-order lag), (K _P + K _i / S) (proportional / integral gain) ) Etc. are considered.
[0034]
FIG. 1 shows a block diagram according to the first embodiment of the present invention based on the knowledge as described above. As shown in the figure, the magnetic flux estimator according to the present embodiment 16 is arranged to calculating a magnetic flux estimation value lambda ^** by applying a predetermined transfer function G to the output V _IP of IP control unit 10. The magnetic flux estimation value λ ^** , which is the calculation result, is supplied to the torque voltage command calculation unit 14 and the torque voltage supply unit 17 in order to correct the linkage flux λ in the equation (2). Since other configurations are the same as those in FIG. 6, the same parts are denoted by the same reference numerals and redundant description is omitted.
[0035]
According to this embodiment, the magnetic flux estimator 16 calculates the formula (9) to obtain the magnetic flux estimated value λ ^** . The torque current command calculation unit 14 obtains the torque current command I _q ^* by performing the calculation of Equation (3) based on the estimated magnetic flux value λ ^** , and supplies this to the current control unit 8. The torque current command I _q ^* can be a command that accurately corresponds to the torque command T ^* by reflecting the actual flux linkage of the permanent magnet with λ.
[0036]
In FIG. 1, the IP control unit 10 may be configured as a PI control unit.
[0037]
Although it considered an ideal state in the controller shown in FIG. 1, in practice the output V _IP of IP control unit 10 may include the components for correcting the voltage drop of the power conversion device (IGBT, etc.) due to the output current become.
[0038]
Here, in I _d = 0 control in which no current flows through the d-axis, the voltage drop of the power conversion element appears only in the q-axis voltage V _q , so that correction can be made with a DC amount on the dq coordinate. . That is, a reference temperature, without compensation of the magnetic flux (magnetic flux is the initial setting) torque command T ^{* (the} torque current command I _{q ^*)} is varied and measuring the output V _IP of IP control unit 10 at that time by words, it is understood voltage drop correction amount V _x based on the voltage drop of the power conversion devices for the torque command T ^*. Therefore, by making this measurement data into a table and adding it to the equation (7), the output V _IP of the IP control unit 10 is obtained by calculating the deviation between the torque voltage command V _q ^* and the torque voltage estimated value V _q ^**. It will reflect accurately.
[0039]
[Equation 5]

[0040]
FIG. 2 shows a block diagram according to the second embodiment of the present invention based on the knowledge as described above. As shown in the figure, the V _x table 18 according to the present embodiment is Yes stores a voltage drop correction amount V _x corresponding to the torque command T ^*, the voltage drop correction amount V _x corresponding to the torque command T ^* output to have configured to sum the output V _IP. Since other configurations are the same as those in FIG. 1, the same parts are denoted by the same reference numerals and redundant description is omitted.
[0041]
According to this embodiment, the magnetic flux can be estimated with high accuracy in the I _d = 0 control, and the torque control accuracy is improved.
[0042]
Furthermore, due to the influence of the switching time of the power conversion element, it is necessary to provide a dead time, which causes an error between the torque voltage command V _q ^* and the actual output voltage. This varies depending on the electrical angular frequency. Therefore, the voltage drop correction amount V _{x of the} control device shown in FIG. 2 is also included in the output VIP of the _IP control unit 10.
[0043]
Here as in the second embodiment, the output V _IP of IP control unit 10 measures the electric angular frequency ω not the torque command T ^* only, the torque command T ^* and 3D for the electrical angular frequency ω When the voltage drop correction amount V _x based on this table is substituted into the equation (10), the output V _IP of the IP control unit 10 becomes the torque voltage command V _q ^* and the torque voltage estimated value V _q ^** . Deviation. The voltage drop correction amount V _{x at} this time represents a correction amount due to the influence of the voltage drop of the power conversion element and the dead time.
[0044]
FIG. 3 shows a block diagram according to the third embodiment of the present invention based on the knowledge as described above. As shown in the figure, the V _x table 18 according to the present embodiment is Yes stores a voltage drop correction amount V _x corresponding to the torque command T ^* and the electrical angular frequency omega, the torque command T ^* and the electrical angular frequency omega It is configured so as to output a voltage drop correction amount V _x is added to the output V _IP corresponding to. Since other configurations are the same as those in FIG. 1, the same parts are denoted by the same reference numerals and redundant description is omitted.
[0045]
According to this embodiment, the magnetic flux can be estimated with high accuracy in the I _d = 0 control, and the torque control accuracy is improved. At this time, the accuracy of magnetic flux estimation and torque control is further improved as compared with the second embodiment.
[0046]
【The invention's effect】
As described above in detail with the embodiment, according to the present invention, since the magnetic flux estimating means uses the output of the torque current command system, it compensates for the demagnetization due to the temperature of the permanent magnet and corresponds to the command value. Not only can accurate control be realized, but also the calculation time for magnetic flux estimation can be shortened. Further, in I _d = 0 control, a correction for the voltage drop of the power conversion element or the influence of the voltage drop and the dead time is added to the torque current command control unit in advance to further improve the magnetic flux estimation and torque control accuracy. Can be improved.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a first embodiment of the present invention.
FIG. 2 is a block diagram showing a second embodiment of the present invention.
FIG. 3 is a block diagram showing a third embodiment of the present invention.
FIG. 4 is a block diagram showing a control device according to the prior art.
FIG. 5 is a characteristic diagram showing temperature characteristics of a permanent magnet.
FIG. 6 is a block diagram showing a control device for explaining the principle of magnetic flux estimation.
[Explanation of symbols]
2 PM motor 10 IP control unit 13 Magnetization current command table 14 Torque current command calculation unit 16 Magnetic flux estimator 17 Torque voltage supply unit 18 V _x table λ ^** Magnetic flux estimation value T ^* Torque command I _d ^* Magnetization current command I _q ^* Torque current command V _d ^* magnetization voltage command V _q ^* torque voltage command ω electrical angular frequency V _q ^** torque voltage estimated value V _IP output V _x voltage drop correction amount

Claims (3)

In a controller for a rotating electrical machine having a permanent magnet as a field, a magnetizing current command table that outputs a magnetizing current command uniquely determined by a torque command and an electrical angular frequency;
Magnetic flux estimating means for calculating a magnetic flux estimated value that is an estimated value of the linkage flux by the current permanent magnet based on a deviation between the torque current command and the torque current detected value fed back;
A control device for a rotating electrical machine, comprising: a torque current command calculation means for outputting a torque current command by a calculation based on a torque command, an electrical angular frequency and a magnetic flux estimation value. In a control device for a rotating electrical machine that has a permanent magnet as a field and performs control to make the magnetization current command zero,
A magnetizing current command table for outputting a magnetizing current command uniquely determined by a torque command and an electrical angular frequency;
Magnetic flux estimating means for calculating a magnetic flux estimated value that is an estimated value of the linkage flux by the current permanent magnet based on a deviation between the torque current command and the torque current detected value fed back;
A torque current command calculating means for outputting a torque current command by a calculation based on the torque command, the electrical angular frequency and the magnetic flux estimated value;
A table of voltage drop due to the power conversion element formed corresponding to the torque command is stored, and a compensation means for compensating for the voltage drop due to the power conversion element based on this table is included. Control device. In a control device for a rotating electrical machine that has a permanent magnet as a field and performs control to make the magnetization current command zero,
A magnetizing current command table for outputting a magnetizing current command uniquely determined by a torque command and an electrical angular frequency;
Magnetic flux estimating means for calculating a magnetic flux estimated value that is an estimated value of the linkage flux by the current permanent magnet based on a deviation between the torque current command and the torque current detected value fed back;
A torque current command calculating means for outputting a torque current command by a calculation based on the torque command, the electrical angular frequency and the magnetic flux estimated value;
A table of voltage drop due to the power conversion element formed corresponding to the torque command and the electrical angular frequency is stored, and compensation means for compensating for the voltage drop due to the power conversion element based on this table is provided. A control device for a rotating electrical machine.

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