JP2004364473A

JP2004364473A - Starting method and device for motor

Info

Publication number: JP2004364473A
Application number: JP2003163355A
Authority: JP
Inventors: Koji Harada; 浩二原田
Original assignee: Nidec Corp
Current assignee: Nidec Corp
Priority date: 2003-06-09
Filing date: 2003-06-09
Publication date: 2004-12-24

Abstract

<P>PROBLEM TO BE SOLVED: To start a sensor-less, three-phase, brushless motor as quickly as possible and surely. <P>SOLUTION: When a starting command is generated, a before-starting conduction control changes over a conducting direction at an interval shorter than a sensitive time of a rotor. Pulse currents are conducted in sequence to the Y-connected, sensor-less, three-phase, brushless motor to be started. During this conduction, whether a voltage on a non-conducting phase winding of the motor is high or low with respect to a neutral point voltage is determined to form non-conducting phase voltage information in each conducting direction. Reference voltage information that corresponds to the non-conducting phase voltage data at the time when the starting command is generated is detected from the reference voltage data of each rotor position of the rotor held in a reference data table. Rotor positions at the time when the starting command is generated are detected from the rotor position of the information. The conducting direction for starting the motor is determined quickly and surely on the basis of this detection. Then, the motor is started by being forcedly conducted in the determined conducting direction. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
この発明は、センサレス方式の３相ブラシレスモータを起動するモータ起動方法及びモータ起動装置に関する。
【０００２】
【従来の技術】
従来、車両の燃料ポンプの駆動モータには、ブラシと整流子（コミュテータ）を有する、いわゆるブラシ付の直流モータが用いられる（例えば、特許文献１参照。）。
【０００３】
そして、前記の燃料ポンプの駆動モータだけでなく、水中ポンプの駆動モータ等の液体に浸漬された状態で使用される種々の機器・装置の駆動や制御のモータには、ブラシ付の直流モータが多用される。
【０００４】
【特許文献１】
特開平１１−３３６６３０号公報（第４頁、図３）
【０００５】
【発明が解決しようとする課題】
前記従来のブラシ付の直流モータは、ブラシ等の磨耗が生じるため、運用中に頻繁に保守作業をする必要がある。
【０００６】
また、前記の磨耗によって生じた粉塵がモータ等に付着して故障が発生する問題もある。
【０００７】
さらに、火花雑音が発生し、周辺の電子機器等に悪影響を与える問題もある。
【０００８】
そこで、ブラシ付の直流モータに代えて、ブラシレスＤＣサーボモータ（３相永久磁石同期モータ）に代表される３相ブラシレスモータを、車両の燃料ポンプの駆動モータ等に用いることが考えられる。
【０００９】
この３相ブラシレスモータは、ブラシがなく、その保守が不要で、粉塵による故障の発生がなく、火花雑音が発生することもない。
【００１０】
しかしながら、この種の３相ブラシレスモータを駆動するため、電磁式、光学式等の位置センサを設けてそのロータ位置を検出し、この検出に基づき、３相巻線の通電方向を切り換えようとすると、位置センサがコイル、ホール素子等の電気・電子部品からなり、その電気特性の変動防止、腐食防止等を図るため、少なくともモータの位置センサ部分を液密な構造にして位置センサを燃料油等から防護する必要が生じ、極めて高価になり、実用的でない。
【００１１】
そこで、この種の３相ブラシレスモータを、位置センサを設けることなく、センサレス方式で用いることが考えられるが、この場合、ロータ位置をどのように検出して起動するかが重要な問題であり、とくに、前記の燃料ポンプの駆動モータ等として用いる場合は、起動の失敗が重大事故にも結びつくことから、極力迅速に、しかも、確実に、起動する必要がある。
【００１２】
そして、センサレス方式の３相ブラシレスモータを起動する最適な構成は、発明されていない。
【００１３】
本発明は、センサレス方式の３相ブラシレスモータを、極力迅速に、しかも、確実に起動することを目的とし、とくに、この種のセンサレス方式の３相ブラシレスモータを車両の燃料ポンプの駆動モータ等として用いる場合に好適なモータ起動方法及びモータ起動装置を提供することを目的とする。
【００１４】
【課題を解決するための手段】
上記した課題を解決するために、本発明のモータ起動方法は、起動指令が発生したときに、起動前通電制御により、Ｙ結線された起動対象のセンサレス方式の３相ブラシレスモータに、ロータの感応時間より短い間隔で通電方向を切り換えて、Ｕ相の巻線からＶ相の巻線、Ｖ相の巻線からＷ相の巻線、Ｗ相の巻線からＵ相の巻線の向きのパルス電流を順に通電し、前記各パルス電流の通電中に前記３相ブラシレスモータの非通電相巻線の電圧の前記Ｙ結線の中点電圧に対する高低を判別して各通電方向の判別結果からなる非通電相電圧情報を形成し、基準情報テーブルに保持された前記３相ブラシレスモータの複数のロータ位置それぞれでの前記非通電相電圧情報からなるロータ位置毎の基準電圧情報から、前記起動指令が発生したときの前記非通電相電圧情報に一致する前記基準電圧情報を検出し、検出した前記基準電圧情報のロータ位置を、前記起動指令が発生したときのロータ位置として検出し、該検出に基づいて前記３相ブラシレスモータの起動の通電方向を決定し、決定した通電方向に前記３相ブラシレスモータを強制通電して起動することを特徴としている（請求項１）。
【００１５】
また、本発明のモータ起動装置は、起動指令の発生により、Ｙ結線された起動対象のセンサレス方式の３相ブラシレスモータに、ロータの感応時間より短い間隔で通電方向を切り換えて、Ｕ相の巻線からＶ相の巻線、Ｖ相の巻線からＷ相の巻線、Ｗ相の巻線からＵ相の巻線にパルス電流を順に通電する起動前通電制御手段と、前記各パルス電流の通電中に前記３相ブラシレスモータの非通電相巻線の電圧の前記Ｙ結線の中性点電圧に対する高低を判別して各通電方向の判別結果からなる非通電相電圧情報を形成する起動前電圧判別手段と、前記３相ブラシレスモータの複数のロータ位置それぞれでの前記非通電相電圧情報からなるロータ位置毎の基準電圧情報を保持した基準情報テーブルと、該テーブルの前記ロータ位置毎の基準電圧情報から、前記起動指令が発生したときの前記非通電相電圧情報に一致する前記基準電圧情報を検出し、検出した前記基準電圧情報のロータ位置を、前記起動指令が発生したときのロータ位置として検出するロータ位置検出手段と、該ロータ位置検出手段の検出に基づいて前記３相ブラシレスモータの起動の通電方向を決定し、決定した通電方向に前記３相ブラシレスモータを強制通電して起動する起動通電制御手段とを備えたことを特徴としている（請求項４）。
【００１６】
これらの構成によれば、起動対象のセンサレス方式の３相ブラシレスモータの起動指令が発生すると、ロータが回転しない微小時間ずつ、モータのＵ相の巻線からＶ相の巻線、Ｖ相の巻線からＷ相の巻線、Ｗ相の巻線からＵ相の巻線の向きのパルス電流が順に通電され、Ｕ相からＶ相の通電時はＷ相の電圧、Ｖ相からＷ相の通電時はＵ相の電圧、Ｗ相からＵ相通電時はＶ相の電圧それぞれの中性点電圧に対する高低を判別して、判別結果の非通電相電圧情報が形成される。
【００１７】
つぎに、基準情報テーブルに保持された複数ロータ位置の基準電圧情報から、起動指令が発生したときの非通電相電圧情報に一致する基準電圧情報が検出され、その基準電圧情報から起動のロータ位置が検出される。
【００１８】
そして、この検出に基づいて起動の通電方向が決定され、決定された通電方向にモータが強制通電されて起動される。
【００１９】
この場合、起動指令が発生したときに、起動のロータ位置が、短時間に、かつ、正確に検出され、この検出に基づき、起動対象のセンサレス方式の３相ブラシレスモータが、極力迅速に、しかも、確実に起動され、主として液体に浸漬されて使用されるこの種のセンサレス方式の３相ブラシレスモータの起動の最適な構成が提供される。
【００２０】
つぎに、本発明のモータ起動方法は、決定した通電方向の強制通電によって所定の時間内に非通電巻線が逆起電圧の発生状態にならないときに、起動前制御に戻して起動の通電方向を再決定し、起動対象のセンサレス方式の３相ブラシレスモータを再起動することを特徴としている（請求項２）。
【００２１】
また、本発明のモータ起動装置は、起動通電制御手段の強制通電によって所定の時間内に非通電巻線が逆起電圧の発生状態にならないときに、前記強制通電から前記起動前通電制御手段による前記各パルス電流の通電に戻して起動の通電方向を再決定し、起動対象のセンサレス方式の３相ブラシレスモータを再起動する再起動制御手段を備えたことを特徴としている（請求項５）。
【００２２】
これらの構成によれば、起動指令が発生したときに、何らかの原因で起動のロータ位置の最初の検出に基づく起動失敗が発生すると、ロータ位置が再検出されて起動の通電方向が再決定され、この再決定に基づき、起動対象のセンサレス方式の３相ブラシレスモータが再起動されて一層確実に起動される。
【００２３】
そして、起動対象のセンサレス方式の３相ブラシレスモータが車両の燃料ポンプの駆動モータであって、起動指令が前記車両のエンジンスタートによって発生することにより（請求項３、６）、ブラシの保守が不要で粉塵による故障や火花雑音のない３相ブラシレスモータを用いた車両の燃料ポンプの信頼性の高い駆動が実現する。
【００２４】
【発明の実施の形態】
起動対象のセンサレス方式の３相ブラシレスモータが車両の燃料ポンプの駆動モータであって、起動指令が車両のエンジンスタートによって発生する場合に適用した本発明の一実施形態について、図１及び図２を参照して説明する。
【００２５】
図１はモータ起動装置を含む起動対象モータの駆動装置のブロック図、図２はその動作説明用のフローチャートである。
【００２６】
図１の起動対象モータ１は車両の燃料ポンプの駆動モータであって、ブラシレスＤＣサーボモータからなり、Ｙ結線された中性点非接地又は中性点接地の３相Ｕ、Ｖ、Ｗの巻線（電機子巻線）１ｕ、１ｖ、１ｗ及び永久磁石（マグネット）のロータを備え、通常運転中は、３相バイポーラブリッジ構成のＰＷＭインバータ２からモータ１の各相の巻線端子ｕ、ｖ、ｗに、例えば１２０度通電の矩形波駆動方式でバイポーラ（交番）のパルス電流が通流して回転する。
【００２７】
また、モータ１、インバータ２を除く図１の各部は、この実施形態にあっては、マイクロコンピュータからなり、このコンピュータが図２のステップＳ１〜Ｓ１５のモータ駆動制御を実行することにより、そのソフトウエア処理によってつぎの各手段が形成される。
【００２８】
（１）起動前通電制御手段
この手段は図１の発振部５、起動前通電制御部６により構成され、起動指令の発生により、モータ１のロータ感応時間より短い間隔で通電方向を切り換えて、モータ１のＵ相の巻線１ｕからＶ相の巻線１ｖ、Ｖ相の巻線１ｖからＷ相の巻線１ｗ、Ｗ相の巻線１ｗからＵ相の巻線１ｕにパルス電流を順に通電する。
【００２９】
（２）起動前電圧判別手段
この手段は図１の微小電圧検出部９、判別部１０により構成され、各パルス電流の通電中にモータ１の非通電相巻線の電圧のＹ結線の中性点電圧に対する高低を判別して各通電方向の判別結果からなる非通電相電圧情報を形成する。
【００３０】
（３）ロータ位置検出手段
この手段は図１のロータ位置検出部１１により構成され、基準情報テーブル１２のロータ位置毎の基準電圧情報から、起動指令が発生したときの非通電相電圧情報に一致する基準電圧情報を検出し、検出した基準電圧情報のロータ位置を、起動指令が発生したときのロータ位置として検出する。
【００３１】
（４）起動通電制御手段
この手段は図１の起動通電決定部１３、起動通電制御部１４により構成され、ロータ位置検出手段の検出に基づいてモータ１の起動の通電方向を決定し、決定した通電方向にモータ１を強制通電して起動する。
【００３２】
（５）再起動制御手段
この手段は図１の逆起電圧検出部１５及び前記の起動前通電制御手段、起動前電圧判別手段、ロータ位置検出手段、起動通電制御手段により構成され、起動通電制御手段の強制通電によって、非通電巻線が逆起電圧の未発生状態になるときに、すなわち、非通電巻線が所定の時間内に逆起電圧の発生状態にならないときに、強制通電から起動前通電制御手段による各パルス電流の通電に戻して起動の通電方向を再決定し、モータ１を再起動する。
【００３３】
そして、モータ１の起動時、起動指令としての車両のエンジンスタートが発生し、イグニッションオン信号が起動指令入力端子３からオアゲート４を介して発振部５に入力されると、図２のステップＳ１を肯定（ＹＥＳ）で通過して発振部５が動作し、モータ１のロータの感応時間より短い間隔、具体的には１ミリ秒（ｍｓ）以下の所定間隔（周期）τで起動前準備のタイミングパルスを３回出力する。
【００３４】
なお、１回目のタイミングパルスは、発振部５の動作開始直後に発生し、２回目、３回目のタイミングパルスは、１回目のタイミングパルスからτ後、２τ後それぞれに発生する。
【００３５】
また、発振部５は、タイミングパルスを３回発生すると、再起動指令又は新たな起動指令の入力待ちの状態になる。
【００３６】
つぎに、発振部５のタイミングパルスが起動前通電制御部６に入力され、この制御部６は、予め設定されたシーケンス動作によってステップＳ２〜Ｓ４を実行し、モータ１の通電方向を、タイミングパルスの入力毎に、Ｕ相の巻線１ｕからＶ相の巻線１ｖ、Ｖ相の巻線１ｖからＷ相の巻線１ｗ、Ｗ相の巻線１ｗからＵ相の巻線１ｕの向きに順に切り換えるように、通常運転中の制御周波数より高周波数の数キロヘルツ〜数十キロヘルツの３相通電制御パルスＳａｕ、Ｓａｖ、Ｓａｗを発生する。
【００３７】
これらの通電制御パルスＳａｕ、Ｓａｖ、Ｓａｗが信号加算部７、起動／通常の制御切換部８を介してインバータ２に供給され、モータ１の通電方向が、瞬時τ毎に、モーター１のＵ相の巻線１ｕからＶ相の巻線１ｖ、Ｖ相の巻線１ｖからＷ相の巻線１ｗ、Ｗ相の巻線１ｗからＵ相の巻線１ｕの向きに順に高速に切り換わるように、インバータ２がスイッチングする。
【００３８】
このとき、モータ１は、Ｕ相の巻線１ｕからＶ相の巻線１ｖ、Ｖ相の巻線１ｖからＷ相の巻線１ｗ、Ｗ相の巻線１ｗからＵ相の巻線１ｕの向きの瞬時τずつのパルス電流の通電により、ロータは回転しないが、ロータと磁極の位置関係及び通電方向に基づき、中性点Ｏの電圧Ｖｏ（接地電位に対する電圧）に対して、非通電相（オープン相）巻線に誘起した微小電圧（接地電位に対する電圧）が高低変化する。
【００３９】
このとき、各通電方向の通電に基づく各オープン相巻線の電圧の高、低（Ｈ、Ｌ）の組み合わせから、モータ１のロータ位置（ポジション）が０度、６０度、１２０度、…、３００度の６０度間隔の機械角度のいずれの位置にあるかがわかり、これからモータ１の起動方向を判別できることが、種々の実験等から判明した。
【００４０】
すなわち、前記の６０度間隔の６ポジションを▲１▼〜▲６▼とすると、巻線１ｕから巻線１ｖ（Ｕ→Ｖ）、巻線１ｖから巻線１ｗ（Ｖ→Ｗ）、巻線１ｗから巻線１ｕ（Ｗ→Ｕ）への通電時、オープン相Ｗ、Ｕ、Ｖの巻線１ｗ、１ｕ、１ｖの微小電圧（各巻１ｕ〜１ｗの端部と接地点との間の電圧）の電圧Ｖｏ（中性点Ｏと接地点との電圧）に対するＨ、Ｌは、つぎの表１に示すようになる。
【００４１】
【表１】

【００４２】
この表１から明らかなように、オープン相Ｗ、Ｕ、Ｖの巻線１ｗ、１ｕ、１ｖの微小電圧Ｖｗ、Ｖｕ、ＶｖのＨ、Ｌの組み合わせは、ロータ位置によって異なる。
【００４３】
そして、前記のＵ→Ｖ、Ｖ→Ｗ、Ｗ→Ｕの通電に基づくＨ、Ｌの組み合わせ（パターン）がわかれば、表１から起動時のロータ位置を正確に判別することができる。
【００４４】
そこで、起動前通電制御部６は通電制御パルスＳａｕ、Ｓａｖ、Ｓａｗの発生に連動して電圧取り込み・判別のタイミング指令を微小電圧検出部９、判別部１０に出力する。
【００４５】
そして、微小電圧検出部９は図２のステップＳ５を実行し、前記のタイミング指令に基づき、Ｕ→Ｖ、Ｖ→Ｗ、Ｗ→Ｕの通電に基づくオープン相Ｗ、Ｕ、Ｖの前記数キロヘルツ〜数十キロヘルツの周波数で変化する微小な電圧Ｖｗ、Ｖｕ、Ｖｖを、周波数フイルタ処理等で抽出して検出し、順次に取り込むと共に、これらの取り込みに同期して電圧Ｖｏも取り込んで判別部１０に転送する。
【００４６】
この判別部１０は、微小電圧検出部９からの電圧Ｖｗ、Ｖｕ、Ｖｖと電圧Ｖｏとの大きさを比較してオープン相Ｗ、Ｕ、Ｖの電圧Ｖｗ、Ｖｕ、ＶｖのＨ、Ｌを判別し、判別結果のＨ、Ｌの組み合わせからなるオープン相電圧情報（非通電相電圧情報）をロータ位置検出部１１に出力する。
【００４７】
一方、不揮発性のメモリからなる基準情報テーブル１２は、前記表１の各ポジション▲１▼〜▲６▼の通電方向とオープン相Ｗ、Ｕ、Ｖの電圧Ｖｗ、Ｖｕ、Ｖｖの組み合わせとからなるロータ位置毎の基準電圧情報を保持する。
【００４８】
そして、ロータ位置検出部１１は図２のステップＳ６を実行し、基準情報テーブル１２の各ポジションの基準電圧情報から、オープン相の電圧情報に一致するＨ、Ｌパターンのポジションの基準電圧情報を検出し、そのポジションから、起動指令が発生したときのロータ位置を検出し、検出したロータ位置の情報を起動通電決定部１３に出力する。
【００４９】
この決定部１３は図２のステップＳ７を実行し、予め設定された各ロータ位置での起動の通電方向から、検出したロータ位置のときの起動の通電方向を決定し、決定した通電方向の情報を起動通電制御部１４に通知する。
【００５０】
そして、起動通電決定部１３の通知に基づき、起動通電制御部１４は図２のステップＳ８を実行し、通常のＰＷＭ運転周波数の３相通電制御パルスＳｂｕ、Ｓｂｖ、Ｓｂｗを、信号加算部７、切換部８を介してインバータ２に供給し、インバータ２を決定した起動の強制転流の通電状態にスイッチングしてモータ１を起動する。
【００５１】
この強制転流の起動でモータ１のロータが回転すると、オープン相の巻線に、所定のしきい値電圧より大きな逆起電力の電圧（逆起電圧）が発生する。
【００５２】
そして、通常運転の逆起電圧検出部１５は図２のステップＳ９を実行し、モータ１の各相の電圧及び電圧Ｖｏから、前記のしきい値電圧より大きな逆起電圧を検出してモータ１の起動を検知すると、その逆起電圧相の検出通知を通常運転通電制御部１６に供給する。
【００５３】
この通常運転通電制御部１６は図２のステップＳ１０を実行し、例えば、逆起電圧検出部１５から通知された逆起電圧（オープン相）と、起動通電制御部１４の３相制御パルスＳｂｕ、Ｓｂｖ、Ｓｂｗとに基づき、モータ１の回転を維持する３相通電制御パルスＳｃｕ、Ｓｃｖ、Ｓｃｗを形成し、これらのパルスＳｃｕ、Ｓｃｖ、Ｓｃｗを、ＰＷＭ制御部１７に供給する。
【００５４】
このＰＷＭ制御部１７は、３相制御パルスＳｃｕ、Ｓｃｖ、Ｓｃｗに基づいて前記の１２０度通電のＰＷＭ制御パルスＳｄｕ、Ｓｄｖ、Ｓｄｗを形成する。
【００５５】
また、モータ１の起動を検知した逆起電圧検出部１５は、ＰＷＭ制御部１７のＰＷＭ制御パルスＳｄｕ、Ｓｄｖ、Ｓｄｗの形成に同期して切換部８を起動側から通常側に切り換える。
【００５６】
この切り換えに基づき、強制転流の通電制御パルスＳｂｕ、Ｓｂｖ、Ｓｂｗに代えて、ＰＷＭ制御部１７のＰＷＭ制御パルスＳｄｕ、Ｓｄｖ、Ｓｄｗが、切換部８からインバータ２に供給される。
【００５７】
この供給に基づき、インバータ２がＰＷＭ制御パルスＳｄｕ、Ｓｄｖ、Ｓｄｗにしたがってスイッチングし、モータ１の通電方向が、そのロータの回転にしたがってセンサレスで切り換えられ、モータ１が回転して給油ポンプが動作する。
【００５８】
この場合、起動指令であるイグニッションオン信号が発生すると、モータ１の通電方向をＵ→Ｖ、Ｖ→Ｗ、Ｗ→Ｕに３回だけ切り換えて得られたオープン相の電圧のＨ、Ｌパターンから、極力迅速に、しかも、確実に、ロータの位置が検出され、この検出に基づき、センサレス方式でモータ１が起動されて車両のエンジンスタートと同時に給油ポンプが確実に動作する。
【００５９】
以降は、車両のエンジンが停止するまで、図２のステップＳ１０、Ｓ１１のループでモータ１が通常運転され、エンジンが停止すると、ステップＳ１１からステップＳ１２に移行してモータ１を停止し、給油ポンプを止める。
【００６０】
ところで、何らかの原因により、イグニッションオン信号が発生した直後の起動の強制転流の通電ではロータが回転しない事態、すなわち、起動失敗が発生したときは、故障が発生したとして、モータ１を停止状態に保ってもよいが、モータ１が車両の給油ポンプの駆動モータの場合等には、起動の失敗による重大事故の発生等を防止するため、起動指令の発生から予め設定されたモータ起動時間内は、再起動を試みることが要求される。
【００６１】
なお、車両の給油ポンプの駆動モータの場合、前記のモータ起動時間は、例えば１５０ｍｓ以下の適当な時間である。
【００６２】
そして、イグニッションオン信号が発生した直後のオープン相の電圧のＨ、Ｌパターンに基づいて最初に決定した起動の転流通電によっては、モータ１が起動しないときは、逆起電圧検出部１５のオープン相の逆起電圧の未検出に基づき、モータ１を再起動する。
【００６３】
すなわち、通電制御パルスＳｂｕ、Ｓｂｖ、Ｓｂｗの出力に連動して起動通電制御部１３から逆起電圧検出部１５に起動スタートが通知され、この通知から、モータ起動時間より短い起動検出の設定時間内に、逆起電圧検出部１５が前記のしきい値電圧より大きな逆起電圧を検出しないとき、換言すれば、所定の時間内にオープン相の巻線に逆起電圧が発生せず、オープン相の巻線が逆起電圧の未発生状態になるときは、図２のステップＳ９からステップＳ１３を介してステップＳ１４に移行して逆起動電圧検出部１５が再起動指令を発生し、この再起動指令が、オアゲート４を介して発振部５に起動指令の代わりに入力される。
【００６４】
このとき、再起動指令によって発振部５が動作し、再び通電制御パルスＳａｕ、Ｓａｖ、Ｓａｗが発生して前記のＵ→Ｖ、Ｖ→Ｗ、Ｗ→Ｕの通電に基づくＨ、Ｌパターンが検出され、この検出に基づいてロータ位置が再検出され、このロータ位置の再検出に基づいて起動の通電方向が再決定され、この再決定に基づいてモータ１が再起動される。
【００６５】
つぎに、モータ起動時間内はモータ１が起動されるまで前記の再起動がくり返され、モータ起動時間が経過してもモータ１が起動しないときは、ステップＳ１３からステップＳ１５に移行し、逆起電圧検出部１５が再起動指令の出力を停止して故障報知部１８に故障報知を指令し、この指令に基づき、故障報知部１８が画面表示や音声、警報音等でモータ１の故障の発生を報知する。
【００６６】
したがって、モータ起動時間内の再起動により、一層確実にモータ１が起動されて信頼性等が一層向上し、しかも、モータ起動時間内にモータ１が起動しなければ、その旨か報知されて信頼性がさらに一層向上する。
【００６７】
そして、本発明は上記した実施形態に限定されるものではなく、その趣旨を逸脱しない限りにおいて上述したもの以外に種々の変更を行うことが可能であり、例えば、起動対象のセンサレス方式の３相ブラシレスモータは、車両の燃料ポンプの駆動モータのような液体に浸漬されて用いられるか否かにかかわらず、種々の機器、装置のモータであってよく、また、位置センサが設けられていないＹ結線のブラシレスＤＣサーボモータ、ブラシレスＤＣモータ等で構成されていてよい。
【００６８】
さらに、起動指令は、電源投入等で自動的に発生するものであってもよく、手動の操作によって発生するものであってもよい。
【００６９】
つぎに、起動前のＵ→Ｖ、Ｖ→Ｗ、Ｗ→Ｕの通電時間やパルス電流の周波数及びモータ起動時間等は実験等に基づいて適当に設定してよく、各手段の構成も図１のものに限られるものではない。
【００７０】
そして、図１のモータ１、インバータ２を除く各部は、図２と異なるモータ駆動制御のソフトウエア処理で形成されていてもよく、ハードウエア回路で形成されていてもよい。
【００７１】
【発明の効果】
以上のように、請求項１、４に記載の発明によれば、起動対象のセンサレス方式の３相ブラシレスモータの起動指令が発生すると、ロータが回転しない微小時間ずつ、モータのＵ相の巻線からＶ相の巻線、Ｖ相の巻線からＷ相の巻線、Ｗ相の巻線からＵ相の巻線の向きのパルス電流を順に通電し、これらの通電の間に、Ｕ相からＶ相の通電時はＷ相の電圧、Ｖ相からＷ相の通電時はＵ相の電圧、Ｗ相からＵ相通電時はＶ相の電圧それぞれの中性点電圧に対する高低を判別して、判別結果の非通電相電圧情報を形成することができる。
【００７２】
さらに、基準情報テーブルに保持された複数ロータ位置の基準電圧情報から、起動指令が発生したときの非通電相電圧情報に一致する基準電圧情報を検出し、その基準電圧情報から、センサレス方式で起動のロータ位置を検出することができる。
【００７３】
そして、この検出に基づいて起動の通電方向を決定し、決定した通電方向にモータを強制通電して起動することができる。
【００７４】
したがって、起動指令が発生したときに、起動のロータ位置を、センサレス方式で、迅速に、かつ、正確に検出し、この検出に基づき、起動対象のセンサレス方式の３相ブラシレスモータを、極力迅速に、しかも、確実に起動することができ、この種のセンサレス方式の３相ブラシレスモータを起動する最適な構成を提供することができる。
【００７５】
また、請求項２、５に記載の発明によれば、起動指令が発生したときに、何らかの原因でロータ位置の最初の検出に基づく起動失敗が発生しても、この起動失敗によって逆起電圧が発生しないときに、ロータ位置の検出をくり返して起動の通電方向を再決定し、この再決定に基づいて、起動対象のセンサレス方式の３相ブラシレスモータを再起動して一層確実に起動することができる。
【００７６】
さらに、請求項３、６に記載の発明によれば、起動対象のセンサレス方式の３相ブラシレスモータが車両の燃料ポンプの駆動モータであって、起動指令が車両のエンジンスタートによって発生するため、センサレス方式の３相ブラシレスモータを用いて、保守が容易で信頼性の高い車両の燃料ポンプの駆動を実現することができる。
【図面の簡単な説明】
【図１】この発明の一実施形態のブロック図である。
【図２】図１の動作説明用のフローチャートである。
【符号の説明】
１起動対象モータ
１ｕ、１ｖ、１ｗ巻線
２ＰＷＭインバータ
５発振部
６起動前通電制御部
９微小電圧検出部
１０判別部
１１ロータ位置検出部
１２基準情報テーブル
１３起動通電決定部
１４起動通電制御部
１５逆起電圧検出部[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a motor starting method and a motor starting device for starting a sensorless three-phase brushless motor.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, a so-called brushed DC motor having a brush and a commutator (a commutator) has been used as a drive motor of a fuel pump of a vehicle (for example, see Patent Document 1).
[0003]
DC motors with brushes are used not only for the drive motor of the fuel pump, but also for the motors for driving and controlling various devices and devices used in a state of being immersed in liquid, such as the drive motor of a submersible pump. Often used.
[0004]
[Patent Document 1]
JP-A-11-336630 (page 4, FIG. 3)
[0005]
[Problems to be solved by the invention]
In the conventional DC motor with a brush, the brush and the like are worn, so that it is necessary to frequently perform maintenance work during operation.
[0006]
In addition, there is also a problem that dust generated by the above-mentioned abrasion adheres to a motor or the like and causes a failure.
[0007]
Further, there is a problem that spark noise is generated and adversely affects peripheral electronic devices and the like.
[0008]
Therefore, it is conceivable to use a three-phase brushless motor typified by a brushless DC servomotor (a three-phase permanent magnet synchronous motor) as a drive motor for a fuel pump of a vehicle, instead of a DC motor with a brush.
[0009]
This three-phase brushless motor has no brushes, does not require maintenance, does not cause breakdown due to dust, and does not generate spark noise.
[0010]
However, in order to drive this type of three-phase brushless motor, a position sensor such as an electromagnetic type or an optical type is provided to detect the rotor position, and based on this detection, it is attempted to switch the energizing direction of the three-phase winding. The position sensor is composed of electric and electronic parts such as coils and Hall elements. To prevent fluctuations in electric characteristics and corrosion, etc., at least the position sensor part of the motor is made to have a liquid-tight structure and the position sensor is made of fuel oil, etc. From the point of view, making it extremely expensive and impractical.
[0011]
Therefore, it is conceivable to use this type of three-phase brushless motor in a sensorless manner without providing a position sensor. In this case, how to detect and start the rotor position is an important problem. In particular, when used as a drive motor for the above-described fuel pump or the like, since starting failure leads to a serious accident, it is necessary to start as quickly and reliably as possible.
[0012]
An optimum configuration for starting the sensorless three-phase brushless motor has not been invented.
[0013]
An object of the present invention is to start a sensorless three-phase brushless motor as quickly and reliably as possible. In particular, this type of sensorless three-phase brushless motor is used as a drive motor for a fuel pump of a vehicle. It is an object of the present invention to provide a motor starting method and a motor starting device suitable for use.
[0014]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, a motor starting method according to the present invention provides a sensor-less three-phase brushless motor of a Y-connected starting target by a pre-start energizing control when a starting command is generated. The energization direction is switched at intervals shorter than the time, and a pulse is applied in the direction from the U-phase winding to the V-phase winding, the V-phase winding to the W-phase winding, and the W-phase winding to the U-phase winding. Currents are sequentially applied, and during the application of the respective pulse currents, the level of the voltage of the non-energized phase winding of the three-phase brushless motor with respect to the midpoint voltage of the Y connection is determined. The activation command is generated from the reference voltage information for each rotor position, which is formed of energized phase voltage information and is the non-energized phase voltage information at each of the plurality of rotor positions of the three-phase brushless motor held in the reference information table. Before Detecting the reference voltage information corresponding to the non-energized phase voltage information, detecting a rotor position of the detected reference voltage information as a rotor position when the start command is generated, and based on the detection, detecting the three-phase brushless An energizing direction for starting the motor is determined, and the three-phase brushless motor is forcibly energized and started in the determined energizing direction (claim 1).
[0015]
In addition, the motor starting device of the present invention switches the energizing direction to the sensorless type three-phase brushless motor of the Y-connection starting target at an interval shorter than the response time of the rotor by generating a start command, thereby generating a U-phase winding. Pre-start energization control means for sequentially energizing a pulse current from a wire to a V-phase winding, a V-phase winding to a W-phase winding, a W-phase winding to a U-phase winding, A pre-start voltage for determining the level of the voltage of the non-energized phase winding of the three-phase brushless motor with respect to the neutral point voltage of the Y connection during energization and forming the non-energized phase voltage information based on the determination result of each energizing direction. Discriminating means, a reference information table holding reference voltage information for each rotor position comprising the non-energized phase voltage information at each of a plurality of rotor positions of the three-phase brushless motor, and a reference voltage for each rotor position of the table. Information Detecting the reference voltage information that matches the non-energized phase voltage information when the start command is generated, and detecting the rotor position of the detected reference voltage information as the rotor position when the start command is generated. A rotor position detecting means, and an energizing control for activating the three-phase brushless motor based on the detection by the rotor position detecting means, and forcibly energizing and starting the three-phase brushless motor in the determined energizing direction. Means (claim 4).
[0016]
According to these configurations, when a start command for the sensorless three-phase brushless motor to be started is generated, the U-phase winding and the V-phase winding of the motor are changed every minute time during which the rotor does not rotate. A pulse current in the direction from the wire to the W-phase winding, from the W-phase winding to the U-phase winding is supplied in order, and when the U-phase to the V-phase is supplied, the W-phase voltage is applied, and the V-phase to the W-phase is supplied. When the U-phase voltage is applied to the U-phase from the W-phase, the voltage relative to the neutral point voltage is determined for each of the V-phase voltages when the U-phase is energized.
[0017]
Next, from the reference voltage information of the plurality of rotor positions held in the reference information table, reference voltage information that matches the non-energized phase voltage information when the start command is generated is detected, and the starting rotor position is detected from the reference voltage information. Is detected.
[0018]
Then, based on this detection, the energizing direction of activation is determined, and the motor is forcibly energized in the determined energizing direction and activated.
[0019]
In this case, when a start command is generated, the start rotor position is detected in a short time and accurately, and based on this detection, the sensorless three-phase brushless motor to be started is quickly and as quickly as possible. Thus, an optimum configuration for starting a sensorless three-phase brushless motor of this type, which is started reliably and mainly used by being immersed in a liquid, is provided.
[0020]
Next, the motor starting method according to the present invention returns to the pre-start control when the non-energized winding does not enter the back electromotive voltage generation state within a predetermined time due to the forced energization in the determined energizing direction. Is determined again, and the sensorless three-phase brushless motor to be started is restarted (claim 2).
[0021]
Further, the motor starting device of the present invention is configured such that when the non-energized winding does not enter a state where a back electromotive voltage is generated within a predetermined time due to the forced energization of the start energizing control means, the forcible energizing control means starts the forcible energization. The present invention is characterized in that there is provided a restart control means for returning to the application of the respective pulse currents, redetermining the energizing direction of the start, and restarting the sensorless three-phase brushless motor to be started (claim 5).
[0022]
According to these configurations, when a start-up command is issued, if a start-up failure based on the first detection of the start-up rotor position occurs for some reason, the rotor position is re-detected and the energizing direction of the start-up is determined again, Based on the redetermination, the sensorless three-phase brushless motor to be started is restarted and started more reliably.
[0023]
The sensor-less three-phase brushless motor to be started is a drive motor for the fuel pump of the vehicle, and the start command is generated by starting the engine of the vehicle (claims 3 and 6), so that brush maintenance is unnecessary. As a result, highly reliable driving of a fuel pump of a vehicle using a three-phase brushless motor free from failure due to dust and spark noise is realized.
[0024]
BEST MODE FOR CARRYING OUT THE INVENTION
FIGS. 1 and 2 show one embodiment of the present invention applied to a case where a sensorless three-phase brushless motor to be started is a drive motor for a fuel pump of a vehicle and a start command is generated by an engine start of the vehicle. It will be described with reference to FIG.
[0025]
FIG. 1 is a block diagram of a driving device for a motor to be started including a motor starting device, and FIG. 2 is a flowchart for explaining the operation.
[0026]
The motor 1 to be started in FIG. 1 is a drive motor for a fuel pump of a vehicle, and is a brushless DC servomotor, and is a three-phase U, V, W winding of a neutral point non-grounded or neutral grounded Y connection. The winding terminals u, v of each phase of the motor 1 are provided from the PWM inverter 2 having a three-phase bipolar bridge configuration during normal operation, including wires (armature windings) 1 u, 1 v, 1 w and a permanent magnet (magnet) rotor. , W, for example, a bipolar (alternating) pulse current flows in a rectangular wave drive system with 120-degree conduction, and rotates.
[0027]
1 except for the motor 1 and the inverter 2 are constituted by a microcomputer in this embodiment, and the computer executes the motor drive control in steps S1 to S15 in FIG. The following means are formed by the wear processing.
[0028]
(1) Pre-start energization control means This means is constituted by the oscillating unit 5 and the pre-start energization control unit 6 shown in FIG. 1, and switches the energization direction at intervals shorter than the rotor-sensitive time of the motor 1 upon generation of a start command. A pulse current is supplied to the U-phase winding 1u to the V-phase winding 1v, the V-phase winding 1v to the W-phase winding 1w, and the W-phase winding 1w to the U-phase winding 1u of the motor 1 in order. I do.
[0029]
(2) Pre-start voltage discriminating means This means is constituted by the minute voltage detecting section 9 and the discriminating section 10 shown in FIG. 1, and the neutral Y connection of the voltage of the non-energized phase winding of the motor 1 during the energization of each pulse current. Non-energized phase voltage information based on the result of determination of each energizing direction is determined by determining the level of the point voltage.
[0030]
(3) Rotor position detecting means This means is constituted by the rotor position detecting unit 11 shown in FIG. 1, and matches the non-energized phase voltage information at the time when the start command is generated from the reference voltage information for each rotor position in the reference information table 12. The detected reference voltage information is detected, and the rotor position of the detected reference voltage information is detected as the rotor position when the start command is generated.
[0031]
(4) Start energization control means This means is constituted by the start energization determination unit 13 and the start energization control unit 14 in FIG. 1, and determines and determines the energization direction for starting the motor 1 based on the detection of the rotor position detection means. The motor 1 is started by forcibly energizing the motor 1 in the energizing direction.
[0032]
(5) Restart control means This means is constituted by the back electromotive voltage detection section 15 of FIG. 1 and the above-described pre-start energization control means, pre-start voltage determination means, rotor position detection means, and start energization control means. When the non-energized winding is in a state where a back electromotive voltage is not generated by the forced energization of the means, that is, when the non-energized winding does not become a state where a back electromotive voltage is generated within a predetermined time, the apparatus is started from the forced energization. Returning to the energization of each pulse current by the pre-energization control means, the energization direction of starting is determined again, and the motor 1 is restarted.
[0033]
When the engine of the vehicle is started as a start command when the motor 1 is started, and an ignition-on signal is input from the start command input terminal 3 to the oscillation unit 5 through the OR gate 4, step S1 in FIG. When the signal passes through the affirmative (YES), the oscillating unit 5 operates, and the pre-start preparation timing is performed at an interval shorter than the response time of the rotor of the motor 1, specifically, at a predetermined interval (period) τ of 1 millisecond (ms) or less. The pulse is output three times.
[0034]
Note that the first timing pulse is generated immediately after the start of the operation of the oscillation unit 5, and the second and third timing pulses are generated τ and 2τ after the first timing pulse, respectively.
[0035]
When the timing pulse is generated three times, the oscillating unit 5 waits for a restart command or a new start command.
[0036]
Next, the timing pulse of the oscillating unit 5 is input to the pre-start energization control unit 6, and the control unit 6 executes steps S2 to S4 by a preset sequence operation, and determines the energization direction of the motor 1 by the timing pulse. , The U-phase winding 1u to the V-phase winding 1v, the V-phase winding 1v to the W-phase winding 1w, and the W-phase winding 1w to the U-phase winding 1u in order. For switching, three-phase energization control pulses Sau, Sav, Saw of several kilohertz to several tens of kilohertz higher than the control frequency during normal operation are generated.
[0037]
These energization control pulses Sau, Sav, Saw are supplied to the inverter 2 via the signal addition unit 7 and the start / normal control switching unit 8, and the energization direction of the motor 1 is changed at every instant τ by the U phase of the motor 1. From the winding 1u to the V-phase winding 1v, from the V-phase winding 1v to the W-phase winding 1w, and from the W-phase winding 1w to the U-phase winding 1u in order. The inverter 2 switches.
[0038]
At this time, the direction of the motor 1 is from the U-phase winding 1u to the V-phase winding 1v, the V-phase winding 1v to the W-phase winding 1w, and the W-phase winding 1w to the U-phase winding 1u. The rotor does not rotate due to the application of the pulse current at each instant τ, but the non-energized phase (voltage with respect to the ground potential) at the neutral point O is determined based on the positional relationship between the rotor and the magnetic pole and the energizing direction. The minute voltage (voltage with respect to the ground potential) induced in the winding (open phase) changes in level.
[0039]
At this time, the rotor position (position) of the motor 1 is 0 degree, 60 degrees, 120 degrees,..., Based on a combination of high and low (H, L) of the voltage of each open phase winding based on the energization in each energization direction. It has been found from various experiments and the like that it is possible to determine which position of the mechanical angle at an interval of 60 degrees of 300 degrees, and to determine the starting direction of the motor 1 from this position.
[0040]
That is, assuming that the six positions at 60-degree intervals are (1) to (6), winding 1u to winding 1v (U → V), winding 1v to winding 1w (V → W), winding 1w When the current flows from the winding 1u (W → U) to the windings 1w, 1u, 1v of the open phases W, U, V, the minute voltage (the voltage between the ends of the windings 1u to 1w and the ground point). H and L with respect to the voltage Vo (voltage between the neutral point O and the ground point) are as shown in Table 1 below.
[0041]
[Table 1]

[0042]
As is clear from Table 1, the combination of H and L of the minute voltages Vw, Vu, Vv of the windings 1w, 1u, 1v of the open phases W, U, V differs depending on the rotor position.
[0043]
If the combination (pattern) of H and L based on the energization of U → V, V → W and W → U is known, the rotor position at the time of starting can be accurately determined from Table 1.
[0044]
Thus, the pre-startup energization control unit 6 outputs a timing command for voltage capture / determination to the minute voltage detection unit 9 and the determination unit 10 in conjunction with generation of the energization control pulses Sau, Sav, Saw.
[0045]
Then, the minute voltage detecting unit 9 executes step S5 in FIG. 2 and, based on the timing command, the open phase W, U, V of the several kilohertz based on the energization of U → V, V → W, W → U. The minute voltages Vw, Vu, Vv, which change at a frequency of up to several tens of kilohertz, are extracted and detected by frequency filter processing and the like, and are sequentially taken in, and the voltage Vo is also taken in synchronism with these taking-in to determine the judgment unit 10. Transfer to
[0046]
The determination unit 10 compares the magnitudes of the voltages Vw, Vu, Vv from the minute voltage detection unit 9 and the voltage Vo to determine the H, L of the voltages Vw, Vu, Vv of the open phases W, U, V. Then, open phase voltage information (non-energized phase voltage information) composed of a combination of H and L as a result of the determination is output to the rotor position detecting unit 11.
[0047]
On the other hand, the reference information table 12 composed of a non-volatile memory includes a combination of the energizing direction of each of the positions (1) to (6) in Table 1 and the voltages Vw, Vu, and Vv of the open phases W, U, and V. Holds reference voltage information for each rotor position.
[0048]
Then, the rotor position detection unit 11 executes step S6 in FIG. 2 to detect, from the reference voltage information of each position in the reference information table 12, reference voltage information of the H and L pattern positions that match the open-phase voltage information. Then, from the position, the rotor position at the time when the start command is generated is detected, and information on the detected rotor position is output to the start energization determining unit 13.
[0049]
The determining unit 13 executes step S7 in FIG. 2 to determine the energizing direction of activation at the detected rotor position from the energizing direction of activation at each preset rotor position, and information on the determined energizing direction. Is notified to the activation energization control unit 14.
[0050]
Then, based on the notification from the start energization determining unit 13, the start energization control unit 14 executes step S8 in FIG. 2 and outputs the three-phase energization control pulses Sbu, Sbv, and Sbw of the normal PWM operation frequency to the signal addition unit 7, The power is supplied to the inverter 2 via the switching unit 8, and the inverter 1 is switched to the energized state of the determined forced commutation to start the motor 1.
[0051]
When the rotor of the motor 1 is rotated by the start of the forced commutation, a voltage of a back electromotive force (back electromotive voltage) larger than a predetermined threshold voltage is generated in the winding of the open phase.
[0052]
Then, the back electromotive voltage detection unit 15 in the normal operation executes step S9 in FIG. 2 to detect a back electromotive voltage larger than the threshold voltage from the voltage and the voltage Vo of each phase of the motor 1, Is detected, the detection notification of the back electromotive force phase is supplied to the normal operation energization control unit 16.
[0053]
The normal operation energization control unit 16 executes step S10 in FIG. 2. For example, the back electromotive voltage (open phase) notified from the back electromotive voltage detection unit 15 and the three-phase control pulse Sbu of the activation energization control unit 14 are output. Based on Sbv and Sbw, three-phase energization control pulses Scu, Scv and Scw for maintaining the rotation of the motor 1 are formed, and these pulses Scu, Scv and Scw are supplied to the PWM control unit 17.
[0054]
The PWM control unit 17 forms the PWM control pulses Sdu, Sdv, Sdw of 120-degree conduction based on the three-phase control pulses Scu, Scv, Scw.
[0055]
Further, the back electromotive voltage detection unit 15 that has detected the start of the motor 1 switches the switching unit 8 from the starting side to the normal side in synchronization with the formation of the PWM control pulses Sdu, Sdv, and Sdw of the PWM control unit 17.
[0056]
Based on this switching, PWM control pulses Sdu, Sdv, Sdw of the PWM control unit 17 are supplied to the inverter 2 from the switching unit 8 instead of the energization control pulses Sbu, Sbv, Sbw of the forced commutation.
[0057]
Based on this supply, the inverter 2 switches according to the PWM control pulses Sdu, Sdv, Sdw, and the energizing direction of the motor 1 is switched sensorlessly according to the rotation of its rotor, and the motor 1 rotates to operate the refueling pump. .
[0058]
In this case, when an ignition-on signal, which is a start command, is generated, the energizing direction of the motor 1 is switched from U to V, V to W, and W to U three times, and the open-phase voltage H and L patterns are obtained. The position of the rotor is detected as quickly and reliably as possible, and based on this detection, the motor 1 is started in a sensorless manner, and the refueling pump operates reliably at the same time as the engine start of the vehicle.
[0059]
Thereafter, the motor 1 is normally operated in a loop of steps S10 and S11 in FIG. 2 until the engine of the vehicle stops, and when the engine stops, the process proceeds from step S11 to step S12, where the motor 1 is stopped and the refueling pump is stopped. Stop.
[0060]
By the way, for some reason, the rotor does not rotate by the energization of forced commutation immediately after the ignition-on signal is generated, that is, when the startup fails, it is determined that a failure has occurred and the motor 1 is stopped. However, in the case where the motor 1 is a drive motor of a fuel pump of a vehicle, for example, in order to prevent the occurrence of a serious accident due to a failure in starting, a motor starting time from a start command is generated within a preset motor starting time. Attempt to restart.
[0061]
In the case of a drive motor for a fuel pump of a vehicle, the above-described motor start-up time is an appropriate time of, for example, 150 ms or less.
[0062]
When the motor 1 is not started by the commutation energization of the start determined first based on the H and L patterns of the open phase voltage immediately after the generation of the ignition ON signal, the back electromotive voltage detection unit 15 is opened. The motor 1 is restarted based on the undetected back electromotive voltage of the phase.
[0063]
That is, in response to the output of the energization control pulses Sbu, Sbv, and Sbw, the start energization control unit 13 notifies the back electromotive voltage detection unit 15 of the start of the start. When the back electromotive voltage detector 15 does not detect a back electromotive voltage larger than the threshold voltage, in other words, no back electromotive voltage is generated in the open phase winding within a predetermined time, and When the winding of FIG. 2 is in a state in which no back electromotive voltage is generated, the process proceeds from step S9 in FIG. 2 to step S14 via step S13, where the reverse starting voltage detection unit 15 generates a restart command, and this restart is performed. A command is input to the oscillation unit 5 via the OR gate 4 instead of the start command.
[0064]
At this time, the oscillating unit 5 is operated by the restart command, and the energization control pulses Sau, Sav, Saw are generated again, and the H and L patterns based on the energization of the above U → V, V → W, W → U are detected. Then, the rotor position is re-detected based on this detection, and the energizing direction of starting is re-determined based on the re-detection of the rotor position, and the motor 1 is restarted based on the re-determination.
[0065]
Next, during the motor start time, the restart is repeated until the motor 1 is started. If the motor 1 does not start even after the motor start time has elapsed, the process proceeds from step S13 to step S15, and vice versa. The electromotive voltage detection unit 15 stops outputting the restart command and instructs the failure notification unit 18 to perform failure notification. Based on this command, the failure notification unit 18 uses a screen display, a sound, an alarm sound, or the like to detect the failure of the motor 1. Report an occurrence.
[0066]
Therefore, the motor 1 is started more reliably by the restart within the motor start time, and the reliability and the like are further improved. Further, if the motor 1 is not started within the motor start time, it is notified that the motor 1 is not started and the reliability is notified. The properties are further improved.
[0067]
The present invention is not limited to the above-described embodiment, and various changes other than those described above can be made without departing from the gist of the present invention. The brushless motor may be a motor of various devices and devices regardless of whether it is used by being immersed in a liquid, such as a drive motor of a fuel pump of a vehicle, and may be a Y motor without a position sensor. It may be composed of a connected brushless DC servo motor, brushless DC motor, or the like.
[0068]
Further, the start command may be automatically generated when the power is turned on, or may be generated by a manual operation.
[0069]
Next, the U-> V, V-> W, W-> U energizing time, pulse current frequency, motor starting time, and the like before starting may be appropriately set based on experiments and the like. It is not limited to those.
[0070]
Each unit except for the motor 1 and the inverter 2 in FIG. 1 may be formed by software processing of motor drive control different from that in FIG. 2 or may be formed by a hardware circuit.
[0071]
【The invention's effect】
As described above, according to the first and fourth aspects of the present invention, when a start command of a sensorless type three-phase brushless motor to be started is generated, the U-phase winding of the motor is set for each minute time during which the rotor does not rotate. From the V-phase winding, from the V-phase winding to the W-phase winding, from the W-phase winding to the U-phase winding in order. When energizing the V phase, the voltage of the W phase, when energizing the V phase to the W phase, the voltage of the U phase, and when energizing the W phase to the U phase, determining the level of the neutral point voltage with respect to the neutral point voltage, The non-energized phase voltage information of the determination result can be formed.
[0072]
Further, based on the reference voltage information of the plurality of rotor positions held in the reference information table, reference voltage information that matches the non-energized phase voltage information when the start command is generated is detected, and the sensor-less start is performed based on the reference voltage information. Can be detected.
[0073]
Then, the energizing direction of the start is determined based on this detection, and the motor can be started by forcibly energizing the motor in the determined energizing direction.
[0074]
Therefore, when a start command is issued, the start rotor position is quickly and accurately detected in a sensorless manner, and based on this detection, the sensorless three-phase brushless motor to be started is moved as quickly as possible. In addition, it is possible to reliably start the motor, and to provide an optimum configuration for starting this type of sensorless three-phase brushless motor.
[0075]
According to the second and fifth aspects of the present invention, when a start-up command is issued, even if a start-up failure based on the first detection of the rotor position occurs for some reason, the start-up failure causes the back electromotive voltage to be reduced. When this does not occur, the detection of the rotor position is repeated to determine again the energizing direction of the start, and based on this redetermination, the sensorless three-phase brushless motor to be started can be restarted to start more reliably. it can.
[0076]
Further, according to the third and sixth aspects of the present invention, the sensorless three-phase brushless motor to be started is a drive motor for the fuel pump of the vehicle, and the start command is generated when the engine of the vehicle is started. By using the three-phase brushless motor of the system, it is possible to realize the driving of the fuel pump of the vehicle which is easy to maintain and has high reliability.
[Brief description of the drawings]
FIG. 1 is a block diagram of one embodiment of the present invention.
FIG. 2 is a flowchart for explaining the operation of FIG. 1;
[Explanation of symbols]
REFERENCE SIGNS LIST 1 Start target motor 1 u, 1 v, 1 w Winding 2 PWM inverter 5 Oscillator 6 Pre-start energization controller 9 Microvoltage detector 10 Discriminator 11 Rotor position detector 12 Reference information table 13 Start energization determiner 14 Starter energization controller 15 Back electromotive voltage detector

Claims

When a start command is generated, the energizing direction is switched by a pre-start energizing control to a three-phase brushless motor of a sensorless type to be Y-connected to be started at an interval shorter than the response time of the rotor. A pulse current in the direction of V-phase winding, V-phase winding to W-phase winding, W-phase winding to U-phase winding is supplied in order, and the three-phase current is supplied during the application of each pulse current. Determining the level of the voltage of the non-energized phase winding of the brushless motor with respect to the neutral point voltage of the Y-connection to form non-energized phase voltage information including the determination result of each energizing direction;
The non-energized phase voltage when the start command is generated from the reference voltage information for each rotor position including the non-energized phase voltage information at each of the plurality of rotor positions of the three-phase brushless motor held in the reference information table. Detecting the reference voltage information that matches the information, detecting the rotor position of the detected reference voltage information as the rotor position when the start command is generated,
A motor starting method, comprising determining an energizing direction for starting the three-phase brushless motor based on the detection, and forcibly energizing and starting the three-phase brushless motor in the determined energizing direction.

When the non-energized winding does not enter the back electromotive voltage generation state within a predetermined time due to the forced energization in the determined energization direction, the control is returned to the pre-start control, the energizing direction of the start is re-determined, and the sensorless method of the start target is used. The method according to claim 1, wherein the three-phase brushless motor is restarted.

The motor starting method according to claim 1, wherein the sensorless three-phase brushless motor to be started is a drive motor of a fuel pump of the vehicle, and the start command is generated by starting the engine of the vehicle.

When a start command is issued, the energizing direction is switched to a Y-connected sensorless three-phase brushless motor to be started at an interval shorter than the response time of the rotor, and the U-phase winding, the V-phase winding, and the V-phase winding are switched. Pre-start energization control means for sequentially applying a pulse current to the W-phase winding, the W-phase winding to the U-phase winding,
During the energization of each of the pulse currents, the level of the voltage of the non-energized phase winding of the three-phase brushless motor with respect to the neutral point voltage of the Y connection is determined, and the non-energized phase voltage information including the determination result of each energizing direction is determined. Pre-start voltage determining means to be formed;
A reference information table holding reference voltage information for each rotor position including the non-energized phase voltage information at each of a plurality of rotor positions of the three-phase brushless motor;
From the reference voltage information for each rotor position in the table, the reference voltage information that matches the non-energized phase voltage information when the start command is generated is detected, and the detected rotor position of the reference voltage information is Rotor position detecting means for detecting as a rotor position when a start command is generated,
Starting energizing control means for determining an energizing direction for starting the three-phase brushless motor based on the detection of the rotor position detecting means, and forcibly energizing and starting the three-phase brushless motor in the determined energizing direction. A motor starting device.

When the non-energized winding does not enter the back electromotive voltage generation state within a predetermined time due to the forced energization of the activation energization control means, the energization is returned from the energized energization control to the energization of the respective pulse currents by the pre-activation energization control means. The motor starting device according to claim 4, further comprising restart control means for re-determining the energizing direction of the motor and restarting the sensorless three-phase brushless motor to be started.

6. The motor starting device according to claim 4, wherein the sensorless three-phase brushless motor to be started is a drive motor of a fuel pump of the vehicle, and the start command is generated by starting the engine of the vehicle.