JP4434402B2

JP4434402B2 - Control device and control method for synchronous motor

Info

Publication number: JP4434402B2
Application number: JP2000017109A
Authority: JP
Inventors: 祐敦稲積; 礼明末吉; 龍一小黒
Original assignee: Yaskawa Electric Corp
Current assignee: Yaskawa Electric Corp
Priority date: 2000-01-26
Filing date: 2000-01-26
Publication date: 2010-03-17
Anticipated expiration: 2020-01-26
Also published as: JP2001211699A

Description

【０００１】
【発明の属する技術分野】
本発明は、ベクトル制御を用いて同期電動機を駆動する制御装置および制御方法に関し、特にモータの回転速度と磁極位置を算出する際に用いる電圧値として指令値を用いるセンサレスベクトル制御を行う同期電動機の制御装置および方法に関する。
【０００２】
【従来の技術】
同期電動機をベクトル制御で駆動する場合、モータの回転速度と磁極位置を外乱オブザーバで推定する方法が提案されている。この外乱オブザーバによる推定には、モータの電流値、電圧値の情報が必要となる。一般に、電流値はセンサで検出しているが、電圧値はセンサで検出するか、もしくは、電圧指令値が替わりに使用される。しかし、モータの回転速度と磁極位置を算出する際に用いる電圧値として電圧指令値を用いることによりセンサを不要とするセンサレスベクトル制御では、電圧指令値と実電圧値との間に誤差が存在するため、この誤差の影響により外乱オブザーバの推定精度が悪化するという問題があった。
【０００３】
【発明が解決しようとする課題】
上述した従来の同期電動機の制御装置および方法では、電圧指令値を用いてモータの回転速度および磁極位置を推定しているため、電圧指令値と実電圧値との間の誤差により外乱オブザーバの推定精度が悪化する場合があるという問題点があった。
【０００４】
本発明の目的は、電圧指令値を用いて回転速度と磁極位置の推定を行うセンサレスベクトル制御を行う場合においても、回転速度および磁極位置を高精度で推定することができる同期電動機の制御装置および制御方法を提供することである。
【０００５】
【課題を解決するための手段】
上記目的を達成するために、本発明の同期電動機の制御方法は、角速度指令値と角速度推定値との偏差からδ軸電流指令値を算出するδ軸速度コントローラと、前記δ軸電流指令値とδ軸電流推定値との偏差からδ軸電圧指令値を算出するδ軸電流コントローラと、γ軸電流指令値とγ軸電流推定値との偏差からγ軸電圧指令値を算出するγ軸電流コントローラと、前記δ軸電圧指令値および前記γ軸電圧指令値と、求められたγ−δ軸位置を入力し、電圧指令絶対値とγ軸からの電圧出力方向の位相である電圧指令位相を算出するベクトル制御回路と、前記ベクトル制御回路において算出された電圧指令絶対値と電圧指令位相を用いて同期電動機の点弧を行うインバータ回路と、前記γ軸電流およびδ軸電流と、前記γ−δ軸の位置と、前記γ軸電圧指令値および前記δ軸電圧指令値を用いた演算を行ない、前記γ軸電流推定値と、前記δ軸電流推定値と、γ軸誘起電圧推定値と、δ軸誘起電圧推定値を算出するγ−δ軸電流・誘起電圧推定器とを備えた同期電動機を制御するための、同期電動機の制御方法であって、
γ軸に電流を流すことにより前記同期電動機の磁軸をγ軸に引き込み、
前記γ軸電流コントローラに対して複数種類のγ軸電流指令値を出力し、その際に前記γ−δ軸電流・誘起電圧推定器から出力されるそれぞれのγ軸誘起電圧推定値の間の偏差を求め、
前記演算において用いられる同期電動機の抵抗値である電動機抵抗値と実際の同期電動機の抵抗値との差である抵抗誤差として複数の値を選択することにより、前記各γ軸誘起電圧推定値の間の偏差が零に近づくような抵抗誤差を求め、
該抵抗誤差が予め定められた一定値以下となった時点におけるγ軸誘起電圧推定値を、前記γ軸電圧指令値と実際のγ軸電圧値との差であるγ軸電圧誤差として前記γ−δ軸電流・誘起電圧推定器に設定されているγ軸電圧値を補正する。
【０００６】
本発明は、γ軸電流指令値を変化させた時のγ−δ軸電流・誘起電圧推定器で推定したγ軸誘起電圧推定値ε^γのオフセットを利用して、同期電動機のγ軸電圧誤差を検出し、γ−δ軸電流・誘起電圧推定器に設定されているγ軸電圧値を補正しているので、センサレスベクトル制御を用いた場合でも高精度な同期電動機の制御を実現することができる。
【０００７】
また、本発明の他の同期電動機の制御方法は、角速度指令値と角速度推定値との偏差からδ軸電流指令値を算出するδ軸速度コントローラと、前記δ軸電流指令値とδ軸電流推定値との偏差からδ軸電圧指令値を算出するδ軸電流コントローラと、γ軸電流指令値とγ軸電流推定値との偏差からγ軸電圧指令値を算出するγ軸電流コントローラと、前記δ軸電圧指令値および前記γ軸電圧指令値と、求められたγ−δ軸位置を入力し、電圧指令絶対値とγ軸からの電圧出力方向の位相である電圧指令位相を算出するベクトル制御回路と、前記ベクトル制御回路において算出された電圧指令絶対値と電圧指令位相を用いて同期電動機の点弧を行うインバータ回路と、前記γ軸電流およびδ軸電流と、前記γ−δ軸の位置と、前記γ軸電圧指令値および前記δ軸電圧指令値を用いた演算を行ない、前記γ軸電流推定値と、前記δ軸電流推定値と、γ軸誘起電圧推定値と、δ軸誘起電圧推定値を算出するγ−δ軸電流・誘起電圧推定器とを備えた同期電動機を制御するための、同期電動機の制御方法であって、
γ軸に電流を流すことにより前記同期電動機の磁軸をγ軸に引き込み、
前記γ軸電流コントローラに対してγ軸電流指令値を出力し、その際に前記γ−δ軸電流・誘起電圧推定器から出力されるδ軸誘起電圧推定値より、前記δ軸電圧指令値と実際のδ軸電圧値との差であるδ軸電圧誤差を算出し、
該δ軸電圧誤差を用いて前記γ−δ軸電流・誘起電圧推定器に設定されているδ軸電圧値を補正する。
【０００８】
本発明は、γ−δ軸電流・誘起電圧推定器で推定したδ軸誘起電圧推定値を利用して、同期電動機のδ軸電圧誤差を検出し、γ−δ軸電流・誘起電圧推定器に設定されているγ軸電圧値を補正しているので、センサレスベクトル制御を用いた場合でも高精度な同期電動機の制御を実現することができる。
【０００９】
【発明の実施の形態】
次に、本発明の実施の形態について図面を参照して詳細に説明する。
【００１０】
（第１の実施形態）
特開平８−３０８２８６号公報に記載されているような同期電動機のセンサレスベクトル制御手法では、回転子の磁軸上に設定されたγ−δ軸座標系に変換されたステータ電流ｉγ、ｉδと、前回推定された電流値
【００１１】
【外１】

【００１２】
との差とγ−δ軸座標系に変換された電圧指令値Ｖγ、Ｖδを入力とし、γ−δ軸座標系における電流
【００１３】
【外２】

【００１４】
と誘起電圧
【００１５】
【外３】

【００１６】
および、回転子の速度
【００１７】
【外４】

【００１８】
を推定している。
【００１９】
ここで、以下
【００２０】
【外５】

【００２１】
を、ｉ^γ（ｋ）、ｉ^δ（ｋ）として表現し、
【００２２】
【外６】

【００２３】
を、ε^γ（ｋ）、ε^δ（ｋ）として表現し、
【００２４】
【外７】

【００２５】
ω^_rmとして表現する。
【００２６】
本実施形態では、このようなセンサレスベクトル制御手法において、時刻ｋ・Ｔｓ秒（但し、ｋ＝０、１、２、３、・・・、Ｔｓはサンプリングタイム）において同期電動機に供給される少なくとも２相分のステータ電流を検出し、回転子上に設定したγ−δ座標系に変換することにより、γ軸電流ｉγ（ｋ）、δ軸電流ｉδ（ｋ）を導出し、前回導出したγ軸電流推定値ｉ^γ（ｋ）、δ軸電流推定値ｉ^δ（ｋ）と、γ軸電圧ｖγ（ｋ）、δ軸電圧ｖδ（ｋ）を用い、同期電動機のγ−δ軸座標系における状態方程式を離散値系に展開した。
【００２７】
【数１】

【００２８】
この式（１）を用いることにより、時刻（ｋ＋１）Ｔｓ秒における電流推定値ｉ^γ（ｋ＋１）、ｉ^δ（ｋ＋１）、誘起電圧推定値ε^γ（ｋ＋１）、ε^δ（ｋ＋１）が求められる。上記の式（１）より、γ軸電圧・電流方程式は、下記の式（２）のように現される。
【００２９】
【数２】

【００３０】
定常状態においては、ｉγ（ｋ＋１）＝ｉγ（ｋ）となるので下記の式（３）が得られる。
【００３１】
【数３】

【００３２】
ここで、γ軸に電流を流し磁極を引き込むとγ−δ軸が回転子磁軸と一致し、γ−δ軸の回転子磁軸のずれ量に相当するε^γ（ｋ）は零となり、このときのγ軸電圧・電流方程式は、下記の式（４）となる。
【００３３】
【数４】

【００３４】
しかし、電動機抵抗値Ｒsに誤差ΔＲsが存在すると、γ軸電圧・電流方程式は、下記の式（５）のようになる。
【００３５】
【数５】

【００３６】
また、ｖγ（ｋ）として、実電圧ではなく電圧指令値を用いるので、実電圧と電圧指令値との間に誤差Δｖγが存在することを考慮すると、γ軸電圧・電流方程式は、下記の式（６）のようになる。
【００３７】
【数６】

【００３８】
ここで、ｖγ（ｋ）＝Ｒs・ｉγ（ｋ）を満たすためにε^γ（ｋ）が発生し、下記の式（７）に示されるような、抵抗誤差ΔＲsを傾きとし、電圧誤差Δｖγを切片とする一次方程式が導き出される。
【００３９】
【数７】

【００４０】
この式（７）を用いて、γ軸に異なる電流を流し、その時のγ軸誘起電圧推定値ε^γ（ｋ）が等しくなるように抵抗誤差ΔＲsを調整し、その時のγ軸誘起電圧推定値ε^γ（ｋ）が零となることにより電圧誤差Δｖγを求め、このγ軸電圧誤差を、同期電動機の回転速度、磁極位置を推定する際に使用するγ軸電圧ｖγ（ｋ）に反映することにより推定精度が高くなる。
【００４１】
本実施形態の同期電動機の制御方法を具体的に構成した制御装置を図１に示す。
【００４２】
本実施形態の同期電動機の制御装置は、δ軸速度コントローラ１と、δ軸電流コントローラ２と、γ軸電流コントローラ３と、ベクトル制御回路４と、インバータ回路５と、相変換器７と、γ−δ軸電流・誘起電圧推定器８と、角速度導出器９と、ずれ角導出器１０と、γ−δ軸位置補正器１１と、γ軸・δ軸電流補正器１２と、電動機定数同定器１３とから構成されている。
【００４３】
そして、本実施形態の同期電動機の制御装置は、角速度指令値ω_rm ^*、γ軸電流指令値ｉγ^*を入力し、同期電動機６の制御を行っている。
【００４４】
δ軸速度コントローラ１は、角速度指令値ω_rm ^*と角速度推定値ω^_rmを入力し、これらの値の偏差からδ軸電流指令値ｉδ^*を算出する。δ軸電流コントローラ２は、δ軸電流指令値ｉδ^*と補正後のδ軸電流推定値ｉ^^δとの偏差からδ軸電圧指令値ｖδ^*を算出する。γ軸電流コントローラ３は、γ軸電流指令値ｉγ^*と補正後のγ軸電流推定値ｉ^＾γとの偏差からγ軸電圧指令値ｖγ^*を算出する。
【００４５】
ベクトル制御回路４は、電圧指令値ｖδ^*とｖγ^*とγ−δ軸位置補正器１１から出力されるγ−δ軸位置を入力し、電圧指令絶対値（ｖδ²＋ｖγ²）^1/2とγ軸からの電圧出力方向の位相である電圧指令位相ｔａｎ^-1（ｖδ／ｖγ）を出力する。インバータ回路５は、ベクトル制御回路４からの電圧指令絶対値（ｖδ²＋ｖγ²）^1/2と電圧指令位相ｔａｎ^-1（ｖδ／ｖγ）を用いて、同期電動機６の点弧を実施する。相変換器７は、同期電動機６のステータ電流ｉ_u、ｉ_vを回転子の磁軸上に設定されたγ−δ軸座標系の電流であるγ軸電流ｉγ、δ軸電流ｉδに変換する。
【００４６】
γ−δ軸電流・誘起電圧推定器８は、相変換器７により変換されたγ軸電流ｉγ、δ軸電流ｉδと、γ−δ軸の位置と、電圧指令値ｖδ^*、ｖγ^*を入力し、上記の式（１）の演算を実施し、γ軸、δ軸電流推定値ｉ^γ、ｉ^δと、γ軸、δ軸誘起電圧推定値ε^γ、ε^δを出力する。また、γ−δ軸電流・誘起電圧推定器８は、電動機定数同定器１３から、抵抗誤差ΔＲs、γ軸電圧誤差Δｖγを入力すると、γ−δ軸電流推定値ｉ^γ、ｉ^δと、γ−δ軸誘起電圧推定値ε^γ、ε^δを算出する際に使用する電動機抵抗値Ｒsおよびγ軸電圧ｖγを補正する。
【００４７】
角速度導出器９は、γ−δ軸電流・誘起電圧推定器８において求められたγ軸誘起電圧推定値ε^γおよびδ軸誘起電圧推定値ε^δを入力し、角速度推定値ω^_rmを算出する。ずれ角導出器１０は、角速度導出器９において算出された角速度推定値ω^_rmと、γ軸誘起電圧推定値ε^γとを用いて、γ−δ軸とｄ−ｑ軸とのずれ角θeを算出する。γ−δ軸位置補正器１１は、ずれ角導出器１０において算出されたずれ角度θeを用いて、γ−δ軸位置の補正を行う。γ軸・δ軸電流補正器１２は、γ−δ軸位置補正器１１により補正されたγ−δ軸位置に基き、δ軸電流推定値ｉ^δおよびγ軸電流推定値ｉ^γを補正し、補正された後のδ軸電流推定値ｉ^^δおよびγ軸電流推定値ｉ^^γとして出力する。
【００４８】
電動機定数同定器１３は、γ軸電流コントローラ３に対して数種類のγ軸電流指令値ｉγ^*を出力し、その時のγ−δ軸電流・誘起電圧推定器８から出力されるそれぞれのγ軸誘起電圧推定値ε^γの偏差が零に近づくように抵抗誤差ΔＲｓを計算し、この偏差が零に近づいた時点でのγ軸誘起電圧推定値ε＾γをγ軸電圧誤差ΔＶγとしてγ−δ軸電流・誘起電圧推定器８に伝達する。
【００４９】
次に、電動機定数同定器１３における処理を図２のフローチャートを参照して説明する。
【００５０】
先ず、γ軸に磁軸を引き込むためにγ軸に図３に示すパターンに従ってγ軸電流ｉγを流す（ステップ１００）。図３において、γ軸電流ｉγを時刻Ｔ₁において引き込み電流ｉγ₀となるように立ち上げ、γ軸電流ｉγがｉγ₀となった状態が安定するようにそのままの状態を時刻Ｔ₂まで維持し、引き込みを完了する（ステップ１１０）。その他のステップでγ軸に電流を流してγ軸誘起電圧推定値ε^γを読み込む時も同様にして時刻Ｔ₁及び時刻Ｔ₂まで待つものとする。
【００５１】
次に、γ軸に電流ｉ₁を流し（ステップ１２０）、その時のγ軸誘起電圧推定値ε^γ₁を求める（ステップ１３０）。さらに、γ軸に電流ｉ₂を流し（ステップ１４０）、その時のγ軸誘起電圧推定値ε^γ₂を求める（ステップ１５０）。ここで、γ軸電流ｉ₁とｉ₂はある程度離れた電流値を設定する。
【００５２】
次に、ステップ１２０及びステップ１４０で与えたγ軸電流ｉ₁、ｉ₂並びにγ軸電流指令値ｉ^*γを変化させた時のステップ１３０、１５０で求めたγ軸誘起電圧ｖγの偏差から、式（７）を用いて抵抗誤差ΔＲsを計算し、現在設定されている電動機抵抗値Ｒsの補正を行う（ステップ１６０）。そして、この抵抗誤差ΔＲsが予め設定された値以下となり電動機抵抗値Ｒsが目標とする精度まで達したと判定されると抵抗誤差計算を完了し、抵抗誤差ΔＲsが予め設定された値より大きい場合には、電動機抵抗値Ｒsは目標とする精度に達していないと判定し、ステップ１２０〜１６０までの処理を電動機抵抗値Ｒsが目標とする精度に達するまで繰り返す（ステップ１７０）。
【００５３】
次に、抵抗誤差ΔＲsが予め設定された値以下となり、電動機抵抗値Ｒsが目標とする精度に達したと判定された時のγ軸誘起電圧推定値ε^γ₁及びε^γ₂の平均値を求め、γ軸電圧誤差Δｖγを求める（ステップ１８０）。
【００５４】
本実施形態では、γ軸電流指令値ｉ^*γを変化させた時のγ−δ軸電流・誘起電圧推定器８で推定したγ軸誘起電圧推定値ε^γのオフセットを利用して、同期電動機６のγ軸電圧誤差Δｖγを検出し、γ−δ軸電流・誘起電圧推定器８に設定されているγ軸電圧値ｖγを補正しているので、センサレスベクトル制御を用いた場合でも高精度な同期電動機６の制御を実現することができる。
【００５５】
（第２の実施形態）
次に、本発明の第２の実施形態の同期電動機の制御方法について説明する。
【００５６】
上記第１の実施形態の同期電動機の制御装置および方法では、γ軸電圧指令値ｖ^*γと、実際のγ軸電圧ｖγとの間の偏差であるγ軸電圧誤差Δｖγを求めて、同期電動機の回転速度、磁極位置の推定を行う際の電圧値の補正を行っている。これに対して、本実施形態の同期電動機の制御方法は、δ軸電圧指令値ｖ^*δと、実際のδ軸電圧ｖδとの間の偏差を求めて、同期電動機の回転速度、磁極位置の推定を行う際の電圧値の補正を行うようにしたものである。
【００５７】
第１の実施形態において示した式（１）を用いることにより、時刻（ｋ＋１）Ｔｓ秒における電流推定値ｉ^γ（ｋ＋１）、ｉ^δ（ｋ＋１）、誘起電圧推定値ε^γ（ｋ＋１）、ε^δ（ｋ＋１）が求められる。上記の式（１）より、δ軸電圧・電流方程式は、下記の式（８）のように現される。
【００５８】
【数８】

【００５９】
定常状態においては、ｉ^δ（ｋ＋１）＝ｉ^δ（ｋ）、ｉγ（ｋ）＝ｉ^γ（ｋ）、ｉδ（ｋ）＝ｉ^δ（ｋ）となるので下記の式（９）が得られる。
【００６０】
【数９】

【００６１】
ここで、無負荷だと、トルク成分電流であるδ軸電流ｉ^δ（ｋ）は零となり、このときのδ軸電圧・電流方程式は、下記の式（１０）となる。
【００６２】
【数１０】

【００６３】
しかし、ｄ軸インダクタンスＬ_dに誤差ΔＬ_dが存在すると、δ軸電圧・電流方程式は、下記の式（１１）のようになる。
【００６４】
【数１１】

【００６５】
また、ｖδ（ｋ）として、実電圧ではなく電圧指令値を用いるので、実電圧と電圧指令値との間にγ軸電圧誤差Δｖδが存在することを考慮すると、δ軸電圧・電流方程式は、下記の式（１２）のようになる。
【００６６】
【数１２】

【００６７】
ここで、式（１０）を満たすためにΔＬ_d・ω^_rm・ｉ^γとΔｖδを打ち消すためのΔε^δが発生し、下記の式（１３）が成立する。
【００６８】
【数１３】

【００６９】
ここで、同期電動機が一定速度で回転しているとすると、式（１３）はΔＬdを傾きとし、電圧誤差Δｖδを切片とする一次方程式となる。γ軸に電流を流し、位相を固定すると、ω^_rm（ｋ）＝０より、上記の式（１３）は下記の式（８）のようになる。
【００７０】
【数１４】

【００７１】
この式（１４）を用いて、γ軸に電流を流し、位相を固定した時のγ軸誘起電圧推定値ε^δ（ｋ）より、実電圧と電圧指令値の間の誤差Δｖδを補正する。
【００７２】
本実施形態の同期電動機の制御方法を具体的に構成した制御装置を図４に示す。
【００７３】
本実施形態の同期電動機の制御装置は、図１に示した第１の実施形態の制御装置に対して、電動機定数同定器１３を電動機定数同定器２３に置き換え、γ-δ軸電流・誘起電圧推定器８をγ-δ軸電流・誘起電圧推定器２８に置き換えたものである。
【００７４】
γ−δ軸電流・誘起電圧推定器２８は、相変換器７により変換されたγ軸電流ｉγ、δ軸電流ｉδと、γ−δ軸の位置と、電圧指令値ｖδ^*、ｖγ^*を入力し、上記の式（１）の演算を実施し、γ軸、δ軸電流推定値ｉ^γ、ｉ^δと、γ軸、δ軸誘起電圧推定値ε^γ、ε^δを出力する。また、γ−δ軸電流・誘起電圧推定器２８は、電動機定数同定器２３から、δ軸電圧誤差Δｖδを入力すると、γ−δ軸電流推定値ｉ^γ、ｉ^δと、γ−δ軸誘起電圧推定値ε^γ、ε^δを算出する際に使用するδ軸電圧ｖδを補正する。
【００７５】
電動機定数同定器２３は、γ軸電流コントローラ３に対してγ軸電流指令値ｉγ^*を出力し、その時のγ−δ軸電流・誘起電圧推定器２８から出力されるδ軸誘起電圧推定値ε^δより、δ軸電圧誤差Δｖδを計算し、このδ軸電圧誤差Δｖδをγ−δ軸電流・誘起電圧推定器２８に伝達する。
【００７６】
また、本実施形態では、角速度指令ω^*rm＝０、角速度推定値ω^rm＝０がδ軸速度コントローラ１に入力される。
【００７７】
次に、本実施形態における電動機定数同定器２３の動作を図５のフローチャートを参照して説明する。
【００７８】
先ず、γ軸に磁軸を引き込むためにγ軸に図３に示すパターンに従ってγ軸電流ｉγを流す（ステップ２００）。図３において、γ軸電流ｉγを時刻Ｔ₁において引き込み電流ｉγ₀となるように立ち上げ、γ軸電流ｉγがｉγ₀となった状態が安定するようにそのままの状態を時刻Ｔ₂まで維持し、引き込みを完了する（ステップ２１０）。その他のステップでγ軸に電流を流してγ軸誘起電圧推定値ε^γを読み込む時も同様にして時刻Ｔ₁及び時刻Ｔ₂まで待つものとする。
【００７９】
次に、その時のδ軸誘起電圧推定値ε^δを求める（ステップ２２０）。
【００８０】
次に、ステップ２２０において求めたδ軸誘起電圧推定値ε^δから、上記の式（１４）を用いてδ軸電圧誤差Δｖδを計算し、γ−δ軸電流・誘起電圧推定器２８に伝達する。γ−δ軸電流・誘起電圧推定器２８では、伝達されたδ軸電圧誤差Δｖδを用いて、電動機の回転速度、磁極位置の推定を行う際に使用するδ軸電圧ｖδの補正を行う（ステップ２３０）。
【００８１】
本実施形態では、γ−δ軸電流・誘起電圧推定器２８で推定したδ軸誘起電圧推定値ε^δを利用して、同期電動機６のδ軸電圧誤差Δｖδを検出し、γ−δ軸電流・誘起電圧推定器２８に設定されているγ軸電圧値ｖδを補正しているので、センサレスベクトル制御を用いた場合でも高精度な同期電動機６の制御を実現することができる。
【００８２】
上記第１および第２の実施形態において説明した同期電動機の制御方法をソフトウェアにより構成してインバータ装置に組み込むようにすることもできる。
【００８３】
【発明の効果】
以上説明したように、本発明は、下記のような効果を有する。
（１）本発明は、γ軸電流指令値を変化させた時のγ−δ軸電流・誘起電圧推定器で推定したγ軸誘起電圧推定値のオフセットを利用して、同期電動機のγ軸電圧誤差を検出し、γ−δ軸電流・誘起電圧推定器に設定されているγ軸電圧値を補正しているので、センサレスベクトル制御を用いた場合でも高精度な同期電動機の制御を実現することができる。
（２）本発明は、γ−δ軸電流・誘起電圧推定器で推定したδ軸誘起電圧推定値を利用して、同期電動機のδ軸電圧誤差を検出し、γ−δ軸電流・誘起電圧推定器に設定されているγ軸電圧値を補正しているので、センサレスベクトル制御を用いた場合でも高精度な同期電動機の制御を実現することができる。
【図面の簡単な説明】
【図１】本発明の第１の実施形態の同期電動機の制御装置の構成を示すブロック図である。
【図２】図１中の電動機定数同定器１３の動作を示すフローチャートである。
【図３】γ軸に磁軸を引き込むためのγ軸電流ｉγの変化を示す図である。
【図４】本発明の第２の実施形態の同期電動機の制御装置の構成を示すブロック図である。
【図５】図４中の電動機定数同定器２３の動作を示すフローチャートである。
【符号の説明】
１ δ軸速度コントローラ
２ δ軸電流コントローラ
３ γ軸電流コントローラ
４ベクトル制御回路
５インバータ回路
６同期電動機
７相変換器
８ γ−δ軸電流・誘起電圧推定器
９角速度導出器
１０ずれ角導出器
１１ γ−δ軸位置補正器
１２ γ軸・δ軸電流補正器
１３電動機定数同定器
２３電動機定数同定器
２８ γ−δ軸電流・誘起電圧推定器
１００、１１０、１２０、１３０、１４０、１５０、１６０、１７０、１８０ステップ
２００、２１０、２２０、２３０ステップ[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a control device and a control method for driving a synchronous motor using vector control, and more particularly to a synchronous motor that performs sensorless vector control using a command value as a voltage value used when calculating a rotation speed and a magnetic pole position of a motor. The present invention relates to a control apparatus and method.
[0002]
[Prior art]
When the synchronous motor is driven by vector control, a method for estimating the rotational speed and magnetic pole position of the motor with a disturbance observer has been proposed. The estimation by the disturbance observer requires information on the motor current value and voltage value. In general, a current value is detected by a sensor, but a voltage value is detected by a sensor, or a voltage command value is used instead. However, in sensorless vector control that does not require a sensor by using a voltage command value as a voltage value used when calculating the rotation speed and magnetic pole position of the motor, there is an error between the voltage command value and the actual voltage value. Therefore, there is a problem that the estimation accuracy of the disturbance observer deteriorates due to the influence of this error.
[0003]
[Problems to be solved by the invention]
In the conventional synchronous motor control apparatus and method described above, the rotational speed of the motor and the magnetic pole position are estimated using the voltage command value. Therefore, the disturbance observer is estimated based on the error between the voltage command value and the actual voltage value. There was a problem that accuracy may deteriorate.
[0004]
An object of the present invention is to provide a control apparatus for a synchronous motor capable of estimating a rotation speed and a magnetic pole position with high accuracy even when performing sensorless vector control for estimating a rotation speed and a magnetic pole position using a voltage command value, and It is to provide a control method.
[0005]
[Means for Solving the Problems]
In order to achieve the above object, a method for controlling a synchronous motor according to the present invention includes a δ-axis speed controller that calculates a δ-axis current command value from a deviation between an angular velocity command value and an estimated angular velocity value, and the δ-axis current command value A δ-axis current controller that calculates a δ-axis voltage command value from the deviation from the δ-axis current estimated value, and a γ-axis current controller that calculates a γ-axis voltage command value from the deviation between the γ-axis current command value and the γ-axis current estimated value Then, the δ-axis voltage command value and the γ-axis voltage command value and the obtained γ-δ axis position are input, and the voltage command absolute value and the voltage command phase that is the phase of the voltage output direction from the γ-axis are calculated. A vector control circuit that performs the ignition of the synchronous motor using the voltage command absolute value and the voltage command phase calculated in the vector control circuit, the γ-axis current and the δ-axis current, and the γ-δ Axis position and the γ-axis voltage command Γ− to calculate the γ-axis current estimated value, the δ-axis current estimated value, the γ-axis induced voltage estimated value, and the δ-axis induced voltage estimated value. A control method for a synchronous motor for controlling a synchronous motor including a δ-axis current / induced voltage estimator,
Pull the magnetic axis of the synchronous motor into the γ-axis by passing a current through the γ-axis,
A plurality of types of γ-axis current command values are output to the γ-axis current controller, and the deviation between the respective γ-axis induced voltage estimated values output from the γ-δ axis current / induced voltage estimator at that time Seeking
By selecting a plurality of values as the resistance error that is the difference between the resistance value of the synchronous motor used in the calculation and the resistance value of the actual synchronous motor, the γ-axis induced voltage estimated value Find the resistance error so that the deviation of
The estimated γ-axis induced voltage at the time when the resistance error becomes equal to or less than a predetermined value is used as the γ-axis voltage error that is the difference between the γ-axis voltage command value and the actual γ-axis voltage value. The γ-axis voltage value set in the δ-axis current / induced voltage estimator is corrected.
[0006]
The present invention uses the offset of the estimated γ-axis induced voltage ε ^ γ estimated by the γ-δ-axis current / induced voltage estimator when the γ-axis current command value is changed to Since the error is detected and the γ-axis voltage value set in the γ-δ-axis current / induced voltage estimator is corrected, highly accurate synchronous motor control can be realized even when sensorless vector control is used. Can do.
[0007]
Further, another method for controlling a synchronous motor according to the present invention includes a δ-axis speed controller that calculates a δ-axis current command value from a deviation between an angular velocity command value and an angular speed estimated value, and the δ-axis current command value and the δ-axis current estimated value. A δ-axis current controller that calculates a δ-axis voltage command value from the deviation from the value, a γ-axis current controller that calculates a γ-axis voltage command value from the deviation between the γ-axis current command value and the γ-axis current estimated value, and the δ A vector control circuit for inputting an axis voltage command value and the γ-axis voltage command value and the obtained γ-δ axis position and calculating a voltage command phase which is a voltage command absolute value and a phase of a voltage output direction from the γ-axis An inverter circuit for starting a synchronous motor using the voltage command absolute value and voltage command phase calculated in the vector control circuit, the γ-axis current and the δ-axis current, and the position of the γ-δ axis, , The γ-axis voltage command value and the δ-axis Γ-δ-axis current / induced to calculate the γ-axis current estimated value, the δ-axis current estimated value, the γ-axis induced voltage estimated value, and the δ-axis induced voltage estimated value by performing calculation using the pressure command value A control method for a synchronous motor for controlling a synchronous motor including a voltage estimator,
Pull the magnetic axis of the synchronous motor into the γ-axis by passing a current through the γ-axis,
A γ-axis current command value is output to the γ-axis current controller, and at that time, the δ-axis voltage command value is calculated from the δ-axis induced voltage estimated value output from the γ-δ-axis current / induced voltage estimator. Calculate the δ-axis voltage error, which is the difference from the actual δ-axis voltage value,
The δ-axis voltage value set in the γ-δ-axis current / induced voltage estimator is corrected using the δ-axis voltage error.
[0008]
The present invention detects a δ-axis voltage error of a synchronous motor using a δ-axis induced voltage estimated value estimated by a γ-δ-axis current / induced voltage estimator, and provides a γ-δ-axis current / induced voltage estimator. Since the set γ-axis voltage value is corrected, highly accurate synchronous motor control can be realized even when sensorless vector control is used.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the present invention will be described in detail with reference to the drawings.
[0010]
(First embodiment)
In a sensorless vector control method of a synchronous motor as described in JP-A-8-308286, stator currents iγ and iδ converted into a γ-δ axis coordinate system set on a magnetic axis of a rotor, Previously estimated current value [0011]
[Outside 1]

[0012]
And the voltage command values Vγ and Vδ converted into the γ-δ axis coordinate system as inputs, and the current in the γ-δ axis coordinate system.
[Outside 2]

[0014]
And induced voltage
[Outside 3]

[0016]
And the speed of the rotor.
[Outside 4]

[0018]
Is estimated.
[0019]
Here, the following [0020]
[Outside 5]

[0021]
Is expressed as i ^ γ (k), i ^ δ (k),
[0022]
[Outside 6]

[0023]
Is expressed as ε ^ γ (k), ε ^ δ (k),
[0024]
[Outside 7]

[0025]
Expressed as ω ^ _rm .
[0026]
In this embodiment, in such a sensorless vector control method, at least 2 supplied to the synchronous motor at time k · Ts seconds (where k = 0, 1, 2, 3,..., Ts is a sampling time). By detecting the stator current of the phase and converting it to the γ-δ coordinate system set on the rotor, the γ-axis current iγ (k) and δ-axis current iδ (k) are derived, and the previously derived γ-axis Γ-δ axis coordinate system of synchronous motor using current estimated value i ^ γ (k), δ-axis current estimated value i ^ δ (k), γ-axis voltage vγ (k), δ-axis voltage vδ (k) The state equation in is expanded into a discrete value system.
[0027]
[Expression 1]

[0028]
By using this equation (1), current estimated values i ^ γ (k + 1), i ^ δ (k + 1), induced voltage estimated values ε ^ γ (k + 1), ε ^ δ (k + 1) at time (k + 1) Ts seconds ) Is required. From the above equation (1), the γ-axis voltage / current equation is expressed as the following equation (2).
[0029]
[Expression 2]

[0030]
In the steady state, since iγ (k + 1) = iγ (k), the following equation (3) is obtained.
[0031]
[Equation 3]

[0032]
Here, when a current is applied to the γ-axis and the magnetic pole is drawn, the γ-δ axis coincides with the rotor magnetic axis, and ε ^ γ (k) corresponding to the deviation of the rotor magnetic axis from the γ-δ axis becomes zero. The γ-axis voltage / current equation at this time is expressed by the following equation (4).
[0033]
[Expression 4]

[0034]
However, if there is an error ΔRs in the motor resistance value Rs, the γ-axis voltage / current equation is as shown in the following equation (5).
[0035]
[Equation 5]

[0036]
Further, since the voltage command value is used as vγ (k) instead of the actual voltage, considering that an error Δvγ exists between the actual voltage and the voltage command value, the γ-axis voltage / current equation is expressed by the following equation: It becomes like (6).
[0037]
[Formula 6]

[0038]
Here, ε ^ γ (k) is generated in order to satisfy vγ (k) = Rs · iγ (k), and the resistance error ΔRs as shown in the following equation (7) is used as the slope, and the voltage error Δvγ. A linear equation with the intercept is derived.
[0039]
[Expression 7]

[0040]
Using this equation (7), a different current is passed through the γ-axis, the resistance error ΔRs is adjusted so that the estimated γ-axis induced voltage ε ^ γ (k) at that time is equal, and the estimated γ-axis induced voltage at that time The voltage error Δvγ is obtained when the value ε ^ γ (k) becomes zero, and this γ-axis voltage error is reflected in the γ-axis voltage vγ (k) used when estimating the rotational speed and magnetic pole position of the synchronous motor. Doing so increases the estimation accuracy.
[0041]
FIG. 1 shows a control device that specifically configures the synchronous motor control method of this embodiment.
[0042]
The control apparatus for the synchronous motor of this embodiment includes a δ-axis speed controller 1, a δ-axis current controller 2, a γ-axis current controller 3, a vector control circuit 4, an inverter circuit 5, a phase converter 7, and γ -Δ-axis current / induced voltage estimator 8, angular velocity derivation unit 9, deviation angle derivation unit 10, γ-δ-axis position correction unit 11, γ-axis / δ-axis current correction unit 12, and motor constant identifier 13.
[0043]
The control device for the synchronous motor of this embodiment inputs the angular velocity command value ω _rm ^* and the γ-axis current command value i γ ^* and controls the synchronous motor 6.
[0044]
The δ-axis speed controller 1 inputs an angular velocity command value ω _rm ^* and an estimated angular velocity value ω ^ _rm , and calculates a δ-axis current command value i δ ^* from a deviation between these values. [delta] axis current controller 2 calculates the [delta] -axis voltage value v? ^* from the deviation between the [delta] -axis current value i? ^* and the corrected [delta]-axis current estimated value i ^^ [delta]. The γ-axis current controller 3 calculates the γ-axis voltage command value vγ ^* from the deviation between the γ-axis current command value iγ ^* and the corrected γ-axis current estimated value i ^^ γ.
[0045]
The vector control circuit 4 inputs the voltage command values vδ ^* and vγ ^* and the γ-δ axis position output from the γ-δ axis position corrector 11, and outputs the voltage command absolute value (vδ ² + vγ ² ) ^1/2 . A voltage command phase tan ⁻¹ (vδ / vγ) that is a phase in the voltage output direction from the γ-axis is output. The inverter circuit 5 performs the ignition of the synchronous motor 6 by using the voltage command absolute value (vδ ² + vγ ² ) ^1/2 and the voltage command phase tan ⁻¹ (vδ / vγ) from the vector control circuit 4. Phase converter 7 converts synchronous stator current i _u of the motor 6, i _v a current at which gamma-axis current iγ of gamma-[delta]-axis coordinate system set on the magnetic axis of the rotor, the [delta] axis current iδ .
[0046]
The γ-δ-axis current / induced voltage estimator 8 inputs the γ-axis current iγ, the δ-axis current iδ converted by the phase converter 7, the position of the γ-δ axis, and the voltage command values vδ ^* , vγ ^* . Then, the above equation (1) is calculated, and the γ-axis and δ-axis current estimated values i ^ γ and i ^ δ and the γ-axis and δ-axis induced voltage estimated values ε ^ γ and ε ^ δ are output. . The γ-δ-axis current / induced voltage estimator 8 receives the resistance error ΔRs and the γ-axis voltage error Δvγ from the motor constant identifier 13, and obtains γ-δ-axis current estimated values i ^ γ, i ^ δ. , The motor resistance value Rs and the γ-axis voltage vγ used when calculating the γ-δ-axis induced voltage estimated values ε ^ γ and ε ^ δ are corrected.
[0047]
The angular velocity derivation unit 9 inputs the γ-axis induced voltage estimated value ε ^ γ and the δ-axis induced voltage estimated value ε ^ δ obtained by the γ-δ-axis current / induced voltage estimator 8 and inputs the angular velocity estimated value ω ^ _rm Is calculated. The deviation angle deriving unit 10 uses the angular velocity estimated value ω ^ _rm calculated by the angular velocity deriving unit 9 and the γ-axis induced voltage estimated value ε ^ γ to produce a deviation angle between the γ-δ axis and the dq axis. θe is calculated. The γ-δ axis position corrector 11 corrects the γ-δ axis position using the shift angle θe calculated by the shift angle deriving unit 10. The γ-axis / δ-axis current corrector 12 corrects the δ-axis current estimated value i ^ δ and the γ-axis current estimated value i ^ γ based on the γ-δ axis position corrected by the γ-δ axis position corrector 11. The corrected δ-axis current estimated value i ^^ δ and γ-axis current estimated value i ^^ γ are output.
[0048]
The motor constant identifier 13 outputs several types of γ-axis current command values iγ ^* to the γ-axis current controller 3, and the respective γ-axis inductions output from the γ-δ-axis current / induced voltage estimator 8 at that time. The resistance error ΔRs is calculated so that the deviation of the estimated voltage value ε ^ γ approaches zero, and the estimated γ-axis induced voltage value ε ^ γ at the time when the deviation approaches zero becomes the γ-axis voltage error ΔVγ, and γ−δ This is transmitted to the shaft current / induced voltage estimator 8.
[0049]
Next, processing in the motor constant identifier 13 will be described with reference to the flowchart of FIG.
[0050]
First, in order to draw the magnetic axis into the γ-axis, a γ-axis current iγ is passed through the γ-axis according to the pattern shown in FIG. In FIG. 3, the γ-axis current iγ is raised so as to become the drawn current iγ ₀ at time T ₁ , and the state is maintained until time T ₂ so that the state where the γ-axis current iγ becomes iγ ₀ is stabilized. Then, the pull-in is completed (step 110). Similarly, when the current is passed through the γ-axis and the estimated γ-axis induced voltage ε ^ γ is read in other steps, the process waits until time T ₁ and time T ₂ .
[0051]
Next, the current i ₁ is passed through the γ-axis (step 120), and the estimated γ-axis induced voltage ε ^ γ ₁ at that time is obtained (step 130). Further, the current i ₂ is passed through the γ axis (step 140), and the estimated γ axis induced voltage ε ^ γ ₂ at that time is obtained (step 150). Here, the γ-axis currents i ₁ and i ₂ are set to current values separated to some extent.
[0052]
Next, from the deviation of the γ-axis induced voltage vγ obtained in

steps

130 and 150 when the γ-axis currents i ₁ and i _{2 and the} γ-axis current command value i ^* γ given in

steps

120 and 140 are changed, The resistance error ΔRs is calculated using equation (7), and the currently set motor resistance value Rs is corrected (step 160). When it is determined that the resistance error ΔRs is equal to or less than a preset value and the motor resistance value Rs has reached the target accuracy, the resistance error calculation is completed, and the resistance error ΔRs is greater than the preset value. Therefore, it is determined that the motor resistance value Rs has not reached the target accuracy, and the processing from steps 120 to 160 is repeated until the motor resistance value Rs reaches the target accuracy (step 170).
[0053]
Next, the average of the estimated γ-axis induced voltages ε ^ γ ₁ and ε ^ γ ₂ when it is determined that the resistance error ΔRs is equal to or less than a preset value and the motor resistance value Rs has reached the target accuracy. A value is obtained to obtain a γ-axis voltage error Δvγ (step 180).
[0054]
In this embodiment, the offset of the estimated γ-axis induced voltage ε ^ γ estimated by the γ-δ-axis current / induced voltage estimator 8 when the γ-axis current command value i ^* γ is changed is used for synchronization. Since the γ-axis voltage error Δvγ of the electric motor 6 is detected and the γ-axis voltage value vγ set in the γ-δ-axis current / induced voltage estimator 8 is corrected, high accuracy is obtained even when sensorless vector control is used. Control of the synchronous motor 6 can be realized.
[0055]
(Second Embodiment)
Next, a control method for the synchronous motor according to the second embodiment of the present invention will be described.
[0056]
In the synchronous motor control device and method of the first embodiment, a synchronous motor is obtained by obtaining a γ-axis voltage error Δvγ which is a deviation between the γ-axis voltage command value v ^* γ and the actual γ-axis voltage vγ. The voltage value at the time of estimating the rotation speed and the magnetic pole position is corrected. On the other hand, the synchronous motor control method of the present embodiment obtains the deviation between the δ-axis voltage command value v ^* δ and the actual δ-axis voltage vδ to determine the rotational speed and magnetic pole position of the synchronous motor. The voltage value at the time of estimation is corrected.
[0057]
By using the equation (1) shown in the first embodiment, the current estimated values i ^ γ (k + 1), i ^ δ (k + 1) and the induced voltage estimated value ε ^ γ (k + 1) at time (k + 1) Ts seconds. ), Ε ^ δ (k + 1). From the above equation (1), the δ-axis voltage / current equation is expressed as the following equation (8).
[0058]
[Equation 8]

[0059]
In the steady state, i ^ δ (k + 1) = i ^ δ (k), iγ (k) = i ^ γ (k), and iδ (k) = i ^ δ (k). ) Is obtained.
[0060]
[Equation 9]

[0061]
Here, when there is no load, the δ-axis current i ^ δ (k) that is the torque component current becomes zero, and the δ-axis voltage / current equation at this time is expressed by the following equation (10).
[0062]
[Expression 10]

[0063]
However, if an error ΔL _d exists in the d-axis inductance L _d , the δ-axis voltage / current equation is as shown in the following equation (11).
[0064]
## EQU11 ##

[0065]
Further, since the voltage command value is used as vδ (k) instead of the actual voltage, considering that the γ-axis voltage error Δvδ exists between the actual voltage and the voltage command value, the δ-axis voltage / current equation is The following equation (12) is obtained.
[0066]
[Expression 12]

[0067]
Here, ΔL _d · ω ^ _rm · i ^ γ and Δε ^ δ for canceling Δvδ are generated to satisfy the equation (10), and the following equation (13) is established.
[0068]
[Formula 13]

[0069]
Assuming that the synchronous motor is rotating at a constant speed, the equation (13) is a linear equation with ΔLd as a slope and a voltage error Δvδ as an intercept. When a current is passed through the γ-axis and the phase is fixed, from ω ^ _rm (k) = 0, the above equation (13) becomes the following equation (8).
[0070]
[Expression 14]

[0071]
Using this equation (14), the error Δvδ between the actual voltage and the voltage command value is corrected from the estimated γ-axis induced voltage value ε ^ δ (k) when a current is passed through the γ-axis and the phase is fixed. .
[0072]
FIG. 4 shows a control device that specifically configures the synchronous motor control method of the present embodiment.
[0073]
The synchronous motor control device according to the present embodiment replaces the motor constant identifier 13 with a motor constant identifier 23 with respect to the control device according to the first embodiment shown in FIG. The estimator 8 is replaced with a γ-δ axis current / induced voltage estimator 28.
[0074]
The γ-δ-axis current / induced voltage estimator 28 receives the γ-axis current iγ and δ-axis current iδ converted by the phase converter 7, the position of the γ-δ axis, and the voltage command values vδ ^* and vγ ^* . Then, the above equation (1) is calculated, and the γ-axis and δ-axis current estimated values i ^ γ and i ^ δ and the γ-axis and δ-axis induced voltage estimated values ε ^ γ and ε ^ δ are output. . Further, when the γ-δ axis current / induced voltage estimator 28 receives the δ-axis voltage error Δvδ from the motor constant identifier 23, the γ-δ-axis current estimated values i ^ γ, i ^ δ, and γ-δ The δ-axis voltage vδ used when calculating the estimated shaft induced voltage values ε ^ γ and ε ^ δ is corrected.
[0075]
The motor constant identifier 23 outputs the γ-axis current command value iγ ^* to the γ-axis current controller 3, and the δ-axis induced voltage estimated value ε output from the γ-δ-axis current / induced voltage estimator 28 at that time. From δ, the δ-axis voltage error Δvδ is calculated, and this δ-axis voltage error Δvδ is transmitted to the γ-δ-axis current / induced voltage estimator 28.
[0076]
In this embodiment, the angular velocity command ω ^* rm = 0 and the estimated angular velocity value ω ^ rm = 0 are input to the δ-axis velocity controller 1.
[0077]
Next, the operation of the motor constant identifier 23 in this embodiment will be described with reference to the flowchart of FIG.
[0078]
First, in order to draw the magnetic axis into the γ-axis, a γ-axis current iγ is supplied to the γ-axis according to the pattern shown in FIG. In FIG. 3, the γ-axis current iγ is raised so as to become the drawn current iγ ₀ at time T ₁ , and the state is maintained until time T ₂ so that the state where the γ-axis current iγ becomes iγ ₀ is stabilized. Then, the pull-in is completed (step 210). Similarly, when the current is passed through the γ-axis and the estimated γ-axis induced voltage ε ^ γ is read in other steps, the process waits until time T ₁ and time T ₂ .
[0079]
Next, the estimated δ-axis induced voltage value ε ^ δ at that time is obtained (step 220).
[0080]
Next, the δ-axis voltage error Δvδ is calculated from the δ-axis induced voltage estimated value ε ^ δ obtained in step 220 using the above equation (14) and transmitted to the γ-δ-axis current / induced voltage estimator 28. To do. The γ-δ axis current / induced voltage estimator 28 uses the transmitted δ axis voltage error Δvδ to correct the δ axis voltage vδ used when estimating the rotation speed and magnetic pole position of the motor (step). 230).
[0081]
In the present embodiment, the δ-axis voltage error Δvδ of the synchronous motor 6 is detected using the δ-axis induced voltage estimated value ε ^ δ estimated by the γ-δ axis current / induced voltage estimator 28, and the γ-δ axis is detected. Since the γ-axis voltage value vδ set in the current / induced voltage estimator 28 is corrected, highly accurate control of the synchronous motor 6 can be realized even when sensorless vector control is used.
[0082]
The synchronous motor control method described in the first and second embodiments may be configured by software and incorporated into the inverter device.
[0083]
【The invention's effect】
As described above, the present invention has the following effects.
(1) The present invention uses the offset of the estimated value of the γ-axis induced voltage estimated by the γ-δ-axis current / induced voltage estimator when the γ-axis current command value is changed, and uses the offset of the γ-axis voltage of the synchronous motor. Since the error is detected and the γ-axis voltage value set in the γ-δ-axis current / induced voltage estimator is corrected, highly accurate synchronous motor control can be realized even when sensorless vector control is used. Can do.
(2) The present invention detects the δ-axis voltage error of the synchronous motor using the δ-axis induced voltage estimated value estimated by the γ-δ-axis current / induced voltage estimator, and detects the γ-δ axis current / induced voltage. Since the γ-axis voltage value set in the estimator is corrected, highly accurate synchronous motor control can be realized even when sensorless vector control is used.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of a synchronous motor control device according to a first embodiment of the present invention;
FIG. 2 is a flowchart showing an operation of an electric motor constant identifier 13 in FIG.
FIG. 3 is a diagram showing a change in a γ-axis current iγ for drawing a magnetic axis into the γ-axis.
FIG. 4 is a block diagram illustrating a configuration of a synchronous motor control device according to a second embodiment of the present invention.
5 is a flowchart showing the operation of an electric motor constant identifier 23 in FIG.
[Explanation of symbols]
1 δ-axis speed controller 2 δ-axis current controller 3 γ-axis current controller 4 vector control circuit 5 inverter circuit 6 synchronous motor 7 phase converter 8 γ-δ-axis current / induced voltage estimator 9 angular velocity deriver 10 deviation angle deriver 11 γ-δ axis position corrector 12 γ-axis / δ-axis current corrector 13 Motor constant identifier 23 Motor constant identifier 28 γ-δ-axis current / induced

voltage estimator

100, 110, 120, 130, 140, 150, 160 170, 180

steps

200, 210, 220, 230 steps

Claims

A δ-axis speed controller that calculates a δ-axis current command value from the deviation between the angular velocity command value and the estimated angular velocity value; and a δ-axis voltage command value that calculates from the deviation between the δ-axis current command value and the δ-axis current estimated value δ An axis current controller, a γ-axis current controller that calculates a γ-axis voltage command value from the deviation between the γ-axis current command value and the estimated γ-axis current value, and the δ-axis voltage command value and the γ-axis voltage command value are obtained. A vector control circuit that inputs the obtained γ-δ axis position, calculates a voltage command absolute value and a voltage command phase that is a phase in the voltage output direction from the γ axis, and a voltage command absolute value calculated by the vector control circuit And an inverter circuit for starting a synchronous motor using a voltage command phase, the γ-axis current and δ-axis current, the position of the γ-δ axis, the γ-axis voltage command value and the δ-axis voltage command value To calculate the γ-axis power For controlling a synchronous motor comprising an estimated value, the δ-axis current estimated value, a γ-axis induced voltage estimated value, and a γ-δ-axis current / induced voltage estimator for calculating a δ-axis induced voltage estimated value A control method for a synchronous motor,
Pull the magnetic axis of the synchronous motor into the γ-axis by passing a current through the γ-axis,
A plurality of types of γ-axis current command values are output to the γ-axis current controller, and the deviation between the respective γ-axis induced voltage estimated values output from the γ-δ axis current / induced voltage estimator at that time Seeking
By selecting a plurality of values as the resistance error that is the difference between the resistance value of the synchronous motor used in the calculation and the resistance value of the actual synchronous motor, the γ-axis induced voltage estimated value Find the resistance error so that the deviation of
The estimated γ-axis induced voltage at the time when the resistance error becomes equal to or less than a predetermined value is used as the γ-axis voltage error that is the difference between the γ-axis voltage command value and the actual γ-axis voltage value. A control method for a synchronous motor that corrects a γ-axis voltage value set in a δ-axis current / induced voltage estimator.

A δ-axis speed controller that calculates a δ-axis current command value from the deviation between the angular velocity command value and the estimated angular velocity value; and a δ-axis voltage command value that calculates from the deviation between the δ-axis current command value and the δ-axis current estimated value δ An axis current controller, a γ-axis current controller that calculates a γ-axis voltage command value from the deviation between the γ-axis current command value and the estimated γ-axis current value, and the δ-axis voltage command value and the γ-axis voltage command value are obtained. A vector control circuit that inputs the obtained γ-δ axis position, calculates a voltage command absolute value and a voltage command phase that is a phase in the voltage output direction from the γ axis, and a voltage command absolute value calculated by the vector control circuit And an inverter circuit for starting a synchronous motor using a voltage command phase, the γ-axis current and δ-axis current, the position of the γ-δ axis, the γ-axis voltage command value and the δ-axis voltage command value To calculate the γ-axis power For controlling a synchronous motor comprising an estimated value, the δ-axis current estimated value, a γ-axis induced voltage estimated value, and a γ-δ-axis current / induced voltage estimator for calculating a δ-axis induced voltage estimated value A control method for a synchronous motor,
Pull the magnetic axis of the synchronous motor into the γ-axis by passing a current through the γ-axis,
A γ-axis current command value is output to the γ-axis current controller, and at that time, the δ-axis voltage command value is calculated from the δ-axis induced voltage estimated value output from the γ-δ-axis current / induced voltage estimator. Calculate the δ-axis voltage error, which is the difference from the actual δ-axis voltage value,
A method for controlling a synchronous motor, wherein the δ-axis voltage value set in the γ-δ-axis current / induced voltage estimator is corrected using the δ-axis voltage error.

A δ-axis speed controller that calculates a δ-axis current command value from the deviation between the angular velocity command value and the estimated angular velocity value;
A δ-axis current controller that calculates a δ-axis voltage command value from a deviation between the δ-axis current command value and the δ-axis current estimated value;
a γ-axis current controller that calculates a γ-axis voltage command value from a deviation between the γ-axis current command value and the γ-axis current estimated value;
A vector for inputting the δ-axis voltage command value and the γ-axis voltage command value and the obtained γ-δ-axis position and calculating a voltage command phase that is a voltage command absolute value and a phase in the voltage output direction from the γ-axis. A control circuit;
In the synchronous motor control device comprising an inverter circuit for starting the synchronous motor using the voltage command absolute value and the voltage command phase calculated in the vector control circuit,
A phase converter for converting the two-phase stator current of the synchronous motor into a γ-axis current and a δ-axis current that are currents in a γ-δ axis coordinate system set on the magnetic axis of the rotor;
Calculation using the γ-axis current and δ-axis current, the position of the γ-δ axis, the γ-axis voltage command value and the δ-axis voltage command value, the γ-axis current estimated value, and the δ-axis The current estimated value, the γ-axis induced voltage estimated value, and the δ-axis induced voltage estimated value are calculated, and the difference between the resistance value of the synchronous motor used in the calculation and the actual resistance value of the synchronous motor is calculated. When the γ-axis voltage error, which is the difference between the γ-axis voltage command value and the actual γ-axis voltage value, is input, the motor resistance value and the γ-axis voltage used in the calculation are corrected. A δ-axis current / induced voltage estimator;
A plurality of types of γ-axis current command values are output to the γ-axis current controller, and the deviation between the respective γ-axis induced voltage estimated values output from the γ-δ axis current / induced voltage estimator at that time The resistance error is calculated such that the resistance error approaches 0, and the estimated γ-axis induced voltage at the time when the harmful resistance error falls below a predetermined value is used as the γ-axis voltage error to estimate the γ-δ-axis current / induced voltage. A control device for a synchronous motor, comprising: an electric motor constant identifier for transmission to a motor.

A δ-axis speed controller that calculates a δ-axis current command value from the deviation between the angular velocity command value and the estimated angular velocity value;
A δ-axis current controller that calculates a δ-axis voltage command value from a deviation between the δ-axis current command value and the δ-axis current estimated value;
a γ-axis current controller that calculates a γ-axis voltage command value from a deviation between the γ-axis current command value and the γ-axis current estimated value;
A vector for inputting the δ-axis voltage command value and the γ-axis voltage command value and the obtained γ-δ-axis position and calculating a voltage command phase that is a voltage command absolute value and a phase in the voltage output direction from the γ-axis. A control circuit;
In the synchronous motor control device comprising an inverter circuit for starting the synchronous motor using the voltage command absolute value and the voltage command phase calculated in the vector control circuit,
A phase converter for converting the two-phase stator current of the synchronous motor into a γ-axis current and a δ-axis current that are currents in a γ-δ axis coordinate system set on the magnetic axis of the rotor;
Calculation using the γ-axis current and δ-axis current, the position of the γ-δ axis, the γ-axis voltage command value and the δ-axis voltage command value, the γ-axis current estimated value, and the δ-axis When calculating a current estimated value, a γ-axis induced voltage estimated value, a δ-axis induced voltage estimated value, and inputting a δ-axis voltage error that is a difference between the δ-axis voltage command value and the actual δ-axis voltage value, A γ-δ axis current / induced voltage estimator for correcting the δ axis voltage used in the calculation;
The γ-axis current command value is output to the γ-axis current controller, and the δ-axis voltage error is calculated from the δ-axis induced voltage estimated value output from the γ-δ-axis current / induced voltage estimator at that time. And a motor constant identifier for transmitting the δ-axis voltage error to the γ-δ-axis current / induced voltage estimator.