JP3770239B2

JP3770239B2 - AC power source direct-coupled brushless DC motor and electrical equipment equipped with the same

Info

Publication number: JP3770239B2
Application number: JP2003025592A
Authority: JP
Inventors: 昌亨高田
Original assignee: Panasonic Corp; Matsushita Electric Industrial Co Ltd
Current assignee: Panasonic Corp; Panasonic Holdings Corp
Priority date: 2003-02-03
Filing date: 2003-02-03
Publication date: 2006-04-26
Anticipated expiration: 2023-02-03
Also published as: JP2004236488A

Description

【０００１】
【発明の属する技術分野】
本発明は、主にパイプファンや天井埋め込み型等の排気用および給気用の換気装置や、送風機、加湿器、除湿機、冷凍機器などのファン駆動用のブラシレスＤＣモータおよびそのブラシレスＤＣモータを搭載した電気機器に関するものである。
【０００２】
【従来の技術】
近年、換気装置等の電気機器に搭載するファン駆動用の電動機においては、低価格化、高効率化、静音化が強く求められており、誘導電動機では大幅な高効率化は困難であることから、永久磁石を使用したブラシレスＤＣモータが増えてきている。一方では、交流電源に接続するだけで簡単に回転するというような、使い勝手の良い電動機も求められている。
【０００３】
従来、この種の電動機は、特許文献１〜３に開示された構成のものが知られている。
【０００４】
以下、その電動機について図９〜図１２を参照しながら説明する。
【０００５】
図に示すように、単一のプリント基板５６に商用のＡＣ電源を整流する整流部５１と、ＤＣモータの２相の駆動コイル５３、５４と、永久磁石５５ａを配した磁石回転子５５と、モータ駆動コイル５３、５４と整流部５１の間には平滑コンデンサ５９として大容量の電解コンデンサを配し、モータ駆動コイル５３、５４に一方向にのみ電流を流すスイッチング素子５７、５８と、このスイッチング素子５７、５８を含め、モータ駆動コイル５３、５４への通電を制御する制御部５２とを備え、整流部５１で整流してなる高圧ＤＣ電源をモータ駆動コイル５３、５４に直接に供給し、整流部５１で整流した高圧ＤＣ電源を減圧して制御部５２に供給するようにした２相半波駆動方式の構成としている。
【０００６】
【特許文献１】
特開２０００−４１３７０号公報
【特許文献２】
特開２０００−４１３９５号公報
【特許文献３】
特開２００２−１０６０９号公報
【０００７】
【発明が解決しようとする課題】
このような従来の電動機によれば、２相半波駆動方式であることから、死点の発生を防止するために、空間高調波トルクを重畳しての対策や、固定子ティースの間隔を変えて対策したとしても、トルクリップル、トルク変化率が大きくなるので、騒音・振動が大きくなり、静音化ができないという課題があり、トルクリップルおよびトルク変化率を小さくし、騒音・振動の発生を抑制することが要求されている。
【０００８】
また、半波駆動方式であることから、電流が大きくなるとともに、負荷トルクに対する電流変化も大きくなるので、使用可能な負荷トルクの範囲が狭くなるという課題があり、電流を小さくでき、使用可能な負荷トルクの範囲が広いことが要求されている。
【０００９】
また、半波駆動方式であることから、出力の高い領域では銅損が極端に大きくなるために、誘導電動機に対しての消費電力の削減効果がなくなってしまうという課題があり、出力の高い領域であっても低消費電力を実現できることが要求されている。
【００１０】
また、整流部で得た高圧ＤＣ電圧を直接駆動電源としているため、安定した高圧ＤＣ電圧を得るためには整流部後段の平滑コンデンサの容量を大きくする必要があり、そのためには電解コンデンサの使用が必須となるので、回路の小型化、品質の安定性確保、長寿命化ができないという課題があった。また、平滑コンデンサの容量を小さくした場合は電源リップルが大きくなるため、トルクリップルが極端に大きくなり振動・騒音がさらに大きくなるとともに、回転むらも極端におおきくなることからファン駆動用に使用した場合、風量がばらつき安定した送風量を確保できないという課題があり、回路の小型化、高品質化、長寿命化を実現した上で、安定した送風量を確保できることが要求されている。
【００１１】
また、電動機をより一層高出力領域で使用するためには、スイッチング素子などの発熱する部品を樹脂にて一体的にモールドすることにより、発熱部品の放熱効果を高くする必要があるが、平滑コンデンサに電解コンデンサを使用した場合は、電解コンデンサの構造上の特性から、モールド成形時には電解液の漏洩による漏れ電流の増加や、アルミ素子の破損の可能性を有し、高温での実使用時においては、電解液の化学反応において発生する水素ガスの拡散が阻害されることによるアルミケースの破裂の可能性を有する等の品質面での課題がある上、電解液の消耗による寿命が確実にあるという課題があり、製造時および実使用時の品質を確保するとともに、発熱部品を含め一体的に樹脂モールドを可能にすることによって、より一層高出力領域での使用を可能にできることが要求されている。
【００１２】
本発明は、このような従来の課題を解決するものであり、トルクリップルおよびトルク変化率を小さくし、騒音・振動の発生を抑制することができ、また、電流を小さくし、使用可能な負荷トルクの範囲が広く、高出力域でも低消費電力を実現でき、回路の小型化、高品質化、長寿命化を実現した上で、回転むらの発生も抑制できる交流電源直結型のブラシレスＤＣモータを提供することを目的としている。
【００１３】
そして、速度調節ができないことから、換気装置における強制換気モードと風量の少ない常時換気モードのどちらかにしか対応できないので、換気装置への搭載が困難であるという課題があり、速度調節ができることが要求されている。
【００１４】
本発明は、このような従来の課題を解決するものであり、任意に速度調節ができる交流電源直結型のブラシレスＤＣモータを提供することを目的としている。
【００１５】
さらには、ダクト式換気装置のようなシロッコファンなど遠心型の送風機を内蔵した機器では、誘導電動機を搭載し、そのトルク特性において起動トルクから最大トルクまでの回転数変化の大きな領域で使用している機器が大半を占めており、このような送風機にブラシレスＤＣモータを搭載して、印加電圧一定で運転した場合、図１２のトルク−回転数特性比較グラフに示すように、最大静圧時の回転数と静圧ゼロ時の回転数差が誘導電動機の場合と比較して極端に小さくなるので、風量−静圧特性において、最大静圧値を誘導電動機搭載時の値と同等にした場合は、静圧ゼロ時の風量が極端に多くなり、騒音・振動が大きくなるうえ、冷暖房エネルギーロスも含めて消費電力の削減効果も少なくなるという課題があり、逆に静圧ゼロ時の風量を同等にした場合は最大静圧の値が極端に低くなり、外風などにより機外圧力損失の変化にともなって風量が大きく変動するという課題があり、誘導電動機を搭載した場合と同等の風量−静圧特性が得られることが要求されている。
【００１６】
本発明は、このような従来の課題を解決するものであり、誘導電動機を搭載した場合と同等の風量−静圧特性を得ることができる交流電源直結型のブラシレスＤＣモータを提供することを目的としている。
【００１７】
【課題を解決するための手段】
本発明のブラシレスＤＣモータは上記目的を達成するために、駆動コイルに所定の方向と順序で順次全波通電するための駆動ロジック制御手段と、交流電源を全波整流する整流手段と、この整流手段によって得た高圧電圧を低圧直流電圧に変換する低圧直流電圧変換手段と、前記駆動ロジック制御手段の出力に基づいて前記低圧直流電圧変換手段によって生成した低圧直流電圧を前記駆動コイルに供給する複数のスイッチング素子と、前記低圧直流電圧変換手段によって生成する低圧直流電圧の値を変更する低圧直流電圧値変更手段と、この低圧直流電圧値変更手段を制御して前記スイッチング素子に供給する平均電流を略一定に制御して出力トルクを略一定に制御する供給電流値制御手段とを配し、前記スイッチング素子に供給される電流を検出する電流検出手段と、前記供給電流値制御手段によって制御する電流値を設定する電流設定手段を備え、この電流設定手段を露出して設けたことを特徴とする交流電源直結型ブラシレスＤＣモータの構成としたものである。
【００１８】
本発明によれば、供給電流値制御手段と、露出して設けた電流設定手段によって、任意に設定したトルクにて略一定運転となり、負荷変化に対する回転数差が大きくなるため、シロッコファンなど遠心型の送風機に搭載しても、最大静圧時の回転数と静圧ゼロ時の回転数差が誘導電動機を搭載した場合と同等になるので、最大静圧が極端に低くなることや、静圧ゼロ時の風量が極端に多くなることを防止できるとともに、静音化、低消費電力化を実現でき、誘導電動機を搭載した場合と同等の風量−静圧特性が任意かつ数多く設定できる交流電源直結型のブラシレスＤＣモータおよび電気機器が得られる。
【００１９】
また他の手段は、磁石回転子の磁束密度分布を検知する磁束密度分布検知手段と、この磁束密度分布検知手段の信号を基に、駆動コイルに所定の方向と順序で順次全波通電するための駆動ロジック制御手段と、交流電源を全波整流する整流手段と、この整流手段によって得た高圧電圧を低圧直流電圧に変換する低圧直流電圧変換手段とを備え、前記磁束密度分布検知手段は検知する磁束密度分布波形が、前記磁石回転子が回転することによって前記駆動コイルに誘起される誘起電圧波形に略相似形となるよう配置し、前記駆動ロジック制御手段には前記磁束密度分布検知手段が検出した波形に略相似形の電流を前記駆動コイルに流す電流波形制御手段を設け、この電流波形制御手段の指示に基づいて前記低圧直流電圧変換手段によって生成した低圧直流電圧を前記駆動コイルに供給する複数のスイッチング素子を備えるとともに、前記低圧直流電圧変換手段によって生成する低圧直流電圧の値を変更する低圧直流電圧値変更手段と、この低圧直流電圧値変更手段を制御して前記スイッチング素子に供給する平均電流を略一定に制御して出力トルクを略一定に制御する供給電流値制御手段とを配し、前記スイッチング素子に供給される電流を検出する電流検出手段と、前記供給電流値制御手段によって制御する電流値を設定する電流設定手段を備え、この電流設定手段を露出して設けたことを特徴とする交流電源直結型ブラシレスＤＣモータの構成としたものである。
【００２０】
本発明によれば、誘起電圧波形と電流波形が略相似形となることから、トルクリップルおよびトルク変化率を小さくし、騒音・振動の発生を抑制するとともに、ブラシレスＤＣモータの効率が大幅に向上するので、使用可能な負荷トルクの範囲が広くなるとともに、銅損が低減できることによって、低消費電力化が実現できる交流電源直結型のブラシレスＤＣモータおよび電気機器が得られる。さらには、低圧直流電圧を駆動コイルに供給することから、全波整流回路の後段に用いる平滑コンデンサの容量を低く抑えることができるので、電解コンデンサを必要としなくなり、回路の大幅な小型化が実現でき、高品質化、長寿命化、回転むらの発生が抑制できるとともに、供給電流値制御手段と露出した電流設定手段によって、任意に設定したトルクにて略一定運転となり、負荷変化に対する回転数差が大きくなるため、シロッコファンなど遠心型の送風機に搭載しても、最大静圧時の回転数と静圧ゼロ時の回転数差が誘導電動機を搭載した場合と同等になるので、最大静圧が極端に低くなることや、静圧ゼロ時の風量が極端に多くなることを防止できるとともに、静音化、低消費電力化を実現でき、誘導電動機を搭載した場合と同等の風量−静圧特性が任意かつ数多く設定できる交流電源直結型のブラシレスＤＣモータおよび電気機器が得られる。
【００２１】
また他の手段は、磁石回転子の磁束密度分布を検知する磁束密度分布検知手段と、この磁束密度分布検知手段の信号を基に、駆動コイルに所定の方向と順序で順次全波通電するための駆動ロジック制御手段と、交流電源を全波整流する整流手段と、この整流手段によって得た高圧電圧を低圧直流電圧に変換する低圧直流電圧変換手段とを備え、前記磁束密度分布検知手段は検知する磁束密度分布波形が、前記磁石回転子が回転することによって前記駆動コイルに誘起される誘起電圧波形に略相似形となるよう配置し、前記駆動ロジック制御手段には前記磁束密度分布検知手段が検出した波形に略相似形の電流を前記駆動コイルに流す電流波形制御手段を設け、この電流波形制御手段の指示に基づいて前記低圧直流電圧変換手段によって生成した低圧直流電圧を前記駆動コイルに供給する複数のスイッチング素子を備えるとともに、前記低圧直流電圧変換手段によって生成する低圧直流電圧の値を変更する低圧直流電圧値変更手段と、この低圧直流電圧値変更手段を制御して前記スイッチング素子に供給する平均電力を略一定に制御する供給電力値制御手段とを配し、この供給電力制御手段によって制御する電力値を設定する電力設定手段を備え、この電力設定手段を露出して設けたことを特徴とする交流電源直結型ブラシレスＤＣモータの構成としたものである。
【００２２】
本発明によれば、誘起電圧波形と電流波形が略相似形となることから、トルクリップルおよびトルク変化率を小さくし、騒音・振動の発生を抑制するとともに、ブラシレスＤＣモータの効率が大幅に向上するので、使用可能な負荷トルクの範囲が広くなるとともに、銅損が低減できることによって、低消費電力化が実現できる交流電源直結型のブラシレスＤＣモータおよび電気機器が得られる。さらには、低圧直流電圧を駆動コイルに供給することから、全波整流回路の後段に用いる平滑コンデンサの容量を低く抑えることができるので、電解コンデンサを必要としなくなり、回路の大幅な小型化が実現でき、高品質化、長寿命化、回転むらの発生が抑制できるとともに、供給電力制御手段と露出した電力設定手段によって、負荷が軽くなるにしたがって電流が低くなり、印加電圧を高くすることになるので、負荷変化に対する回転数差が大きくなることとなり、シロッコファンなど遠心型の送風機に搭載しても、最大静圧時の回転数と静圧ゼロ時の回転数差が誘導電動機を搭載した場合と同等になるので、最大静圧が極端に低くなることや、静圧ゼロ時の風量が極端に多くなることを防止できるとともに、静音化、低消費電力化を実現でき、誘導電動機を搭載した場合と同等の風量−静圧特性が任意かつ数多く設定できる交流電源直結型のブラシレスＤＣモータおよび電気機器が得られる。
【００２３】
また他の手段は、磁束密度分布検知手段が検出した波形のうち２相分の波形を合成する磁束密度分布波形合成手段を設け、駆動ロジック制御手段は前記磁束密度分布波形合成手段が合成した波形に略相似形の電流を駆動コイルに流すことを特徴とする交流電源直結型ブラシレスＤＣモータの構成としたものである。
【００２４】
本発明によれば、電流波形における３次調波や５次調波などの高調波成分が除去できることから、瞬時トルクに高調波成分の含有を抑制した低騒音化・低振動化が可能な交流電源直結型のブラシレスＤＣモータおよび電気機器が得られる。
【００２５】
また他の手段は、ＰＷＭ制御することによって、電流波形を形成することを特徴とする交流電源直結型ブラシレスＤＣモータの構成としたものである。
【００２６】
本発明によれば、スイッチング素子の発熱を抑制できるので、使用可能な負荷トルクの範囲がさらに広くできる交流電源直結型のブラシレスＤＣモータおよび電気機器が得られる。
【００２７】
また他の手段は、前記磁石回転子の永久磁石は極異方性磁石としたことを特徴とする交流電源直結型ブラシレスＤＣモータの構成としたものである。
【００２８】
本発明によれば、誘起電圧波形と電流波形が略正弦波となることから、トルクリップルおよびトルク変化率をより一層小さくし、騒音・振動の発生をさらに抑制した低騒音化・低振動化が可能な交流電源直結型のブラシレスＤＣモータおよび電気機器が得られる。
【００２９】
【発明の実施の形態】
請求項１に記載の発明は、駆動コイルに所定の方向と順序で順次全波通電するための駆動ロジック制御手段と、交流電源を全波整流する整流手段と、この整流手段によって得た高圧電圧を低圧直流電圧に変換する低圧直流電圧変換手段と、前記駆動ロジック制御手段の出力に基づいて前記低圧直流電圧変換手段によって生成した低圧直流電圧を前記駆動コイルに供給する複数のスイッチング素子と、前記低圧直流電圧変換手段によって生成する低圧直流電圧の値を変更する低圧直流電圧値変更手段と、この低圧直流電圧値変更手段を制御して前記スイッチング素子に供給する平均電流を略一定に制御して出力トルクを略一定に制御する供給電流値制御手段とを配し、前記スイッチング素子に供給される電流を検出する電流検出手段と、前記供給電流値制御手段によって制御する電流値を設定する電流設定手段を備え、この電流設定手段を露出して設けたことを特徴とする交流電源直結型ブラシレスＤＣモータの構成としたものであり、供給電流値制御手段と露出して設けた電流設定手段によって、任意に設定したトルクにて略一定運転となるという作用を有する。
【００３０】
請求項２に記載の発明は、磁石回転子の磁束密度分布を検知する磁束密度分布検知手段と、この磁束密度分布検知手段の信号を基に、駆動コイルに所定の方向と順序で順次全波通電するための駆動ロジック制御手段と、交流電源を全波整流する整流手段と、この整流手段によって得た高圧電圧を低圧直流電圧に変換する低圧直流電圧変換手段とを備え、前記磁束密度分布検知手段は検知する磁束密度分布波形が、前記磁石回転子が回転することによって前記駆動コイルに誘起される誘起電圧波形に略相似形となるよう配置し、前記駆動ロジック制御手段には前記磁束密度分布検知手段が検出した波形に略相似形の電流を前記駆動コイルに流す電流波形制御手段を設け、この電流波形制御手段の指示に基づいて前記低圧直流電圧変換手段によって生成した低圧直流電圧を前記駆動コイルに供給する複数のスイッチング素子を備えるとともに、前記低圧直流電圧変換手段によって生成する低圧直流電圧の値を変更する低圧直流電圧値変更手段と、この低圧直流電圧値変更手段を制御して前記スイッチング素子に供給する平均電流を略一定に制御して出力トルクを略一定に制御する供給電流値制御手段とを配し、前記スイッチング素子に供給される電流を検出する電流検出手段と、前記供給電流値制御手段によって制御する電流値を設定する電流設定手段を備え、この電流設定手段を露出して設けたことを特徴とする交流電源直結型ブラシレスＤＣモータの構成としたものであり、誘起電圧波形と電流波形が略相似形となることから、トルクリップルおよびトルク変化率が小さくなるとともに、効率を大幅に向上でき、低圧直流電圧を駆動コイルに供給することから、全波整流回路の後段に用いる平滑コンデンサの容量を低く抑えることができるという作用を有するとともに、供給電流値制御手段と露出した電流設定手段によって、任意に設定したトルクにて略一定運転となるという作用を有する。
【００３１】
請求項３に記載の発明は、磁石回転子の磁束密度分布を検知する磁束密度分布検知手段と、この磁束密度分布検知手段の信号を基に、駆動コイルに所定の方向と順序で順次全波通電するための駆動ロジック制御手段と、交流電源を全波整流する整流手段と、この整流手段によって得た高圧電圧を低圧直流電圧に変換する低圧直流電圧変換手段とを備え、前記磁束密度分布検知手段は検知する磁束密度分布波形が、前記磁石回転子が回転することによって前記駆動コイルに誘起される誘起電圧波形に略相似形となるよう配置し、前記駆動ロジック制御手段には前記磁束密度分布検知手段が検出した波形に略相似形の電流を前記駆動コイルに流す電流波形制御手段を設け、この電流波形制御手段の指示に基づいて前記低圧直流電圧変換手段によって生成した低圧直流電圧を前記駆動コイルに供給する複数のスイッチング素子を備えるとともに、前記低圧直流電圧変換手段によって生成する低圧直流電圧の値を変更する低圧直流電圧値変更手段と、この低圧直流電圧値変更手段を制御して前記スイッチング素子に供給する平均電力を略一定に制御する供給電力値制御手段とを配し、この供給電力制御手段によって制御する電力値を設定する電力設定手段を備え、この電力設定手段を露出して設けたことを特徴とする交流電源直結型ブラシレスＤＣモータの構成としたものであり、誘起電圧波形と電流波形が略相似形となることから、トルクリップルおよびトルク変化率が小さくなるとともに、効率を大幅に向上でき、低圧直流電圧を駆動コイルに供給することから、全波整流回路の後段に用いる平滑コンデンサの容量を低く抑えることができるという作用を有するとともに、供給電力制御手段と露出した電力設定手段によって、負荷が軽くなるにしたがって電流が低くなり、印加電圧を高くするという作用を有する。
【００３２】
請求項４に記載の発明は、磁束密度分布検知手段が検出した波形のうち２相分の波形を合成する磁束密度分布波形合成手段を設けるとともに、特に請求項２、３記載の駆動ロジック制御手段を前記磁束密度分布波形合成手段が合成した波形に略相似形の電流を前記駆動コイルに流す駆動ロジック制御手段にすることにより、電流波形における３次調波や５次調波などの高調波成分が除去できるという作用を有する。
【００３３】
請求項５に記載の発明は、特に請求項２、３記載の駆動ロジック制御手段をＰＷＭ制御することによって、電流波形を形成する駆動ロジック制御手段にすることにより、スイッチング素子の発熱を抑制できるという作用を有する。
【００３４】
請求項６に記載の発明は、特に請求項２、３記載の磁石回転子の永久磁石を極異方性磁石とすることにより、誘起電圧波形と電流波形が略正弦波となることから、トルクリップルおよびトルク変化率をより一層小さくするという作用を有する。
【００３５】
以下、本発明の実施例について図１〜図９を参照しながら説明する。
【００３６】
【実施例】
（実施例１）
図１〜図３に示すように、１は交流電源直結型のブラシレスＤＣモータで、１０は複数のスロットを有する固定子鉄心１０ａに絶縁材にて形成されたインシュレータ１１を介して駆動コイル２を巻装した固定子で、固定子１０は熱硬化性樹脂２１にてモールド成形されて外被を形成しており、１７はブラケットで軸受け２０を保持している。３は磁石回転子であり、プラスチックマグネットを射出成形時に極配向させてシャフト１９と一体成形して形成しており、主磁極部は極異方性磁石３ａとなっている。２２はプリント基板で、電子部品等を実装、はんだ付けしている。熱硬化性樹脂２１にて形成した外被の一部にはプリント基板２２に達するまでの凹部２４を設けている。４は極異方性磁石３ａの磁束密度分布を検知する磁束密度分布検知手段となるホール素子で、このホール素子４の検知した波形が極異方性磁石３ａによって駆動コイル２に誘起される誘起電圧波形と略相似となるようにホール素子４と極異方性磁石３ａの空隙を設定して配置している。１２は磁束密度分布波形合成手段で、駆動コイル２のｕ相に供給する電流波形の高調波成分を除去するために、ホール素子４のｕ相波形からｖ相波形を減算し、同様に駆動コイル２のｖ相にはホール素子４のｖ相波形からｗ相波形を減算し、駆動コイルのｗ相にはホール素子４のｗ相波形からｕ相波形を減算している。５は駆動ロジック制御手段で、駆動コイル２に所定の方向と順序で順次全波通電となるようスイッチング素子のＯＮ・ＯＦＦを制御し、電流波形制御手段７は磁束密度分布波形合成手段１２によって高調波成分を除去した波形に略相似形になるように、スイッチング素子６が飽和に近い非飽和状態になるようにフィードバックしながら出力バイアス電流を調整する。１５は商用交流電源を接続する交流電源接続手段であり、９は交流電源を全波整流する整流手段で、８は整流手段９にて全波整流されたリプルを有する高圧の電圧を４５Ｖ以下の略平坦な低圧直流電圧に変換する低圧直流電圧変換手段で、この低圧直流電圧変換手段８にて変換された低圧直流電圧はスイッチング素子６を介して駆動コイル２に供給されるとともに、駆動ロジック制御手段５等への制御電源としても供給される。そして、低圧直流電圧変換手段８と整流手段９の間には、交流１００Ｖ５０Ｈｚを全波整流した時に４５Ｖ以下となる２．１ミリ秒の期間の電圧を補う小容量の平滑コンデンサ１８を配している。１３は電圧設定手段であり、凹部２４に露出している。２３は低圧直流電圧変換手段８にて生成した電圧と電圧設定手段１３にて出力される電圧の比によって、低圧直流電圧変換手段８にて生成する低圧直流電圧値を指示する生成電圧指示手段であり、１４は生成電圧指示手段２３の指示により、低圧直流電圧変換手段８にて生成する低圧直流電圧値を変更する低圧直流電圧値変更手段である。そして、図１において一点鎖線にて囲まれた電子部品の内、低圧直流電圧変換手段８を構成する部品の一つとなるチョークコイルと２次側平滑コンデンサを除いて、アルミナ製基板の上に実装、配線接続、フェノール系樹脂にて保護コートして形成したワンチップＩＣ１６の構成になっている。
【００３７】
このような本発明の交流電源直結型のブラシレスＤＣモータ１によれば、全波整流する整流手段９によって整流されたリプルを有する高圧電圧を、低圧直流電圧変換手段８が４５Ｖ以下の略平坦な低圧直流電圧に変換し、駆動電源として駆動コイル２に供給することにより、全波整流後の平滑コンデンサ１８は電圧不足となる非常に短い期間（例えば、ＡＣ１００Ｖ５０Ｈｚの場合は２．１ミリ秒）を補うだけの容量に低く抑えることができるので、コンデンサの小型化、省スペース化ができるとともに、電解コンデンサを使用しなくても、セラミックコンデンサやフイルムコンデンサを使用できるため、温度特性の変化がない、電解液の漏洩、枯渇等がないなどの高品質化、長寿命化および大幅な小型化ができるとともに、発熱部品を含め一体的に樹脂モールドすることが可能になるので、より一層高出力領域での使用が可能となる交流電源直結型のブラシレスＤＣモータが得られる。
【００３８】
また、露出して設けた電圧設定手段１３により、低圧直流電圧の値が任意に変更できることから、複数段の速度調節が可能となるとともに、モータが機器に搭載された後であっても、その機器の性能の調整を必要に応じて、その都度容易にできるので、モータ搭載機器の標準化に貢献できる交流電源直結型のブラシレスＤＣモータが得られる。
【００３９】
また、平滑コンデンサ１８の容量が少なくても、低圧直流電圧変換手段８が略平坦な低圧直流電圧にするので、トルクリップルや回転むらを抑えた交流電源直結型のブラシレスＤＣモータが得られる。そして、ファン駆動用に使用しても回転が安定するので、送風量の安定化が実現できる。
【００４０】
また、駆動ロジック制御手段５が３相全波駆動することにより、死点を考慮する必要がなくなるうえ、トルクリップルやトルク変化率を小さくでき、駆動電流を小さくできるとともに、高出力領域での銅損を削減できるため、騒音・振動の発生を抑制し、使用可能な負荷トルクの範囲が広く、高出力領域であっても低消費電力を実現できる交流電源直結型のブラシレスＤＣモータが得られる。
【００４１】
また、磁束密度分布検知手段４の検知する波形が極異方性磁石３ａによって駆動コイル２に誘起される誘起電圧波形と略相似となるように磁束密度分布検知手段４と磁石の空隙を設定して配置し、電流波形制御手段７は磁束密度分布検知手段４が検知した磁束密度分布波形に略相似形の電流を駆動コイル２に流すことにより、誘起電圧波形と電流波形が略相似となるので、トルクリップルおよびトルク変化率を一層低く抑えることができるとともに、モータ効率が大幅に向上するため、低騒音化、高効率化を実現した交流電源直結型のブラシレスＤＣモータが得られる。
【００４２】
また、磁石回転子３の主磁極部を極異方性磁石３ａとすることにより、誘起電圧波形も電流波形もともに正弦波となることから、トルクリップルおよびトルク変化率をより一層低く抑えることができるとともに、モータ効率も大幅に向上するので、静音化、高効率化を実現した交流電源直結型のブラシレスＤＣモータが得られる。
【００４３】
また、磁束密度分布波形合成手段１２が、磁束密度分布検知手段４が検知したｕ相、ｖ相、ｗ相の波形を合成することにより、各相の磁束密度分布検知手段４のばらつきの影響が小さくなるとともに、ｕ相、ｖ相、ｗ相各相の磁束密度分布波形は、基本的には位相が単にずれただけの波形であることから、２相を減算合成することにより、検知した磁束密度分布波形に含まれた高調波成分が除去されるので、回転むらの発生が抑制できるとともに、トルクリップルおよびトルク変化率をさらに低く抑えることができるため、高品質化を実現した交流電源直結型のブラシレスＤＣモータが得られる。
【００４４】
なお、本実施例１では駆動コイル２に供給される電流波形を、誘起電圧波形に略相似形となるように構成したが、用途、商品の要求される騒音レベルに応じて、１２０度矩形波通電や、１４０度、１５０度通電のように広角通電方式としても良く、低圧直流電圧を駆動電源として駆動コイル２に供給することにより、全波整流後の平滑コンデンサの容量を低く抑え、回転むらを抑制し、高出力領域での銅損の削減による、大幅な小型化、高品質化、長寿命化、使用可能な負荷トルクの範囲が広く、高出力領域であっても低消費電力を実現できる交流電源直結型のブラシレスＤＣモータが得られることに差異は生じない。
【００４５】
また、本実施例１では磁束密度分布検知手段４を用いた構成としたが、非通電相に誘起される誘起電圧や、電流を検知して磁石回転子に対する通電位相を決める方式としても良く、その作用効果に差異を生じない。
【００４６】
また、本実施例１ではスイッチング素子６が飽和に近い非飽和状態になるようにフィードバックしながら出力バイアス電流を調整したが、スイッチング素子６をＰＷＭ制御して電流波形を制御しても良く、その場合にはスイッチング素子６の損失が低減できるので、スイッチング素子６の発熱が抑制され、使用可能な負荷トルクの範囲がさらに広くできる交流電源直結型のブラシレスＤＣモータが得られることとなる。
【００４７】
また、本実施例１では低圧直流電圧変換手段８が４５Ｖ以下の略平坦な低圧直流電圧に変換したが、３６Ｖ以下の低圧直流電圧に変換するならば、１．７ミリ秒の期間を補うだけのコンデンサ容量にさらに低く抑えることができることとなる。
【００４８】
また、本実施例１ではスイッチング素子６に供給する低圧直流電圧を低圧直流電圧変換手段８にて生成した電圧と電圧設定手段１３にて出力される電圧の比によって、低圧直流電圧変換手段８にて生成する低圧直流電圧値を指示する生成電圧指示手段２３と、この生成電圧指示手段２３の指示により、低圧直流電圧変換手段８にて生成する低圧直流電圧値を変更する低圧直流電圧値変更手段１４を設けて可変する構成としたが、出力の低いブラシレスＤＣモータにおいては、図４に示すように低圧直流電圧変換手段８より出力される低圧直流電圧を抵抗分圧回路等にて降圧し、その降圧した直流電圧をスイッチング素子に供給する構成としても良くその作用効果に差異を生じない。
（実施例２）
図５〜図７に示すように、３１は換気装置の一種である天井埋め込み型の換気扇であり、交流電源直結型のブラシレスＤＣモータ２９をファン駆動用として搭載している。２６はスイッチング素子６に供給される電流を検知する電流検出手段で、２７は供給電流値制御手段である。この供給電流値制御手段２７は電流検出手段２６にて検出するスイッチング素子６に供給される平均電流値が設定された電流値と同等になるように、低圧直流電圧値変更手段１４を制御することにより、低圧直流電圧変換手段８から出力される電圧を可変しながらフィードバック制御する。２５は電流設定手段で、低圧直流電圧変換手段８にて生成した低圧直流電圧を抵抗分圧回路などにて減圧して供給電流値指示電圧に変換し、凹部２４に露出して配置されている。２８は供給電流値変更手段で、低圧直流電圧変換手段８にて生成した低圧直流電圧と電流設定手段２５にて生成した低圧直流電圧との比に応じて、供給電流値制御手段２７が略一定に制御する平均電流値を決定する。そして、図５において一点鎖線にて囲まれた電子部品の内、低圧直流電圧変換手段８を構成する部品の一つとなるチョークコイルと２次側平滑コンデンサを除いて、アルミナ製基板の上に実装、配線接続、フェノール系樹脂にて保護コートして形成したワンチップＩＣ３０の構成になっており、その他の構成において、実施例１と同一部分には同一番号を付し、詳細な説明は省略する。
【００４９】
このような本発明の交流電源直結型のブラシレスＤＣモータ２９によれば、供給電流値制御手段２７がスイッチング素子６に供給する平均電流を略一定に制御するので、出力トルクが略一定運転となり、負荷変化に対する回転数差が大きくなるため、シロッコファンなど遠心型の送風機を搭載した換気装置３１においては、最大静圧時の回転数と静圧ゼロ時の回転数差が誘導電動機を搭載した場合と同等になるので、最大静圧が極端に低くなることや、静圧ゼロ時の風量が極端に多くなることを防止できるとともに、静音化、低消費電力化を実現できる。
【００５０】
また、電流設定手段２５を露出させて設け、この電流設定手段２５の生成する電圧に応じて供給電流値変更手段２８が供給電流値制御手段２７にて略一定制御する平均電流値を変更する構成とすることにより、無段階で任意のトルクで略一定運転ができることとなり、シロッコファンなど遠心型の送風機に搭載した時に、誘導電動機を搭載した場合と同様の風量−静圧特性が無段階で設定できる交流電源直結型のブラシレスＤＣモータ２９およびそのブラシレスＤＣモータ２９を搭載した換気装置３１などの電気機器が得られる。さらには、モータが機器に搭載された後であっても、その機器の性能の調整を容易にできる交流電源直結型のブラシレスＤＣモータが得られる。
【００５１】
なお、本実施例２ではスイッチング素子６に供給する電流を略一定に制御する構成としたが、図８に示すように、供給電流値制御手段２７を供給電力制御手段３３に置き換え、供給電流値変更手段２８を供給電力変更手段３４に置き換え、電流設定手段２５を電力設定手段３２に置き換えた交流電源直結型のブラシレスＤＣモータ３５の構成とすることにより、モータにかかる負荷が軽くなるにしたがって供給電流が低くなり、それに応じて印加電圧を高くすることになり、逆に負荷が重くなれば供給電流が高くなるので、印加電圧を低くするので、負荷変化に対する回転数差が大きくなることとなり、シロッコファンなど遠心型の送風機に搭載しても、最大静圧時の回転数と静圧ゼロ時の回転数差が誘導電動機を搭載した場合と同等になるので、最大静圧が極端に低くなることや、静圧ゼロ時の風量が極端に多くなることを防止できるとともに、負荷変動に対して消費電力の変化がなく、静音化、低消費電力化を実現できるため、誘導電動機を搭載した場合と同様の風量−静圧特性が無段階設定できる交流電源直結型のブラシレスＤＣモータおよびそのブラシレスＤＣモータを搭載した電気機器が得られることとなる。さらには、モータが機器に搭載された後であっても、その機器の性能の調整を必要に応じて容易にできるので、モータ搭載機器の標準化に貢献できる交流電源直結型のブラシレスＤＣモータが得られる。
【００５２】
【発明の効果】
以上の実施例から明らかなように、本発明によれば、全波整流する整流手段によって整流されたリプルを有する高圧電圧を、低圧直流電圧変換手段が４５Ｖ以下の略平坦な低圧直流電圧に変換し、駆動電源として駆動コイルに供給することにより、全波整流後の平滑コンデンサは電圧不足となる非常に短い期間（例えば、ＡＣ１００Ｖ５０Ｈｚならば２．１ミリ秒）を補うだけの容量に低く抑えることができるので、コンデンサの小型化、省スペース化ができるとともに、電解コンデンサを使用しなくても、セラミックコンデンサやフイルムコンデンサを使用できるため、大幅な小型化や、温度特性の変化がないなどの高品質化、大幅な長寿命化ができるとともに、トルクリップルや回転むらの発生を抑制できる交流電源直結型のブラシレスＤＣモータが得られる。そして、ファン駆動用に使用しても送風量の安定化が実現できる。
【００５３】
また、駆動ロジック制御手段が３相全波駆動することにより、死点を考慮する必要がなくなるうえ、トルクリップルやトルク変化率を小さくでき、駆動電流を小さくできるとともに、高出力領域での銅損を削減できるため、騒音・振動の発生を抑制し、使用可能な負荷トルクの範囲が広く、高出力領域であっても低消費電力を実現できる交流電源直結型のブラシレスＤＣモータが得られる。
【００５４】
また、磁束密度分布検知手段の検知する波形が磁石回転子によって駆動コイルに誘起される誘起電圧波形と略相似となるように磁束密度分布検知手段と磁石の空隙を設定して配置し、電流波形制御手段は磁束密度分布検知手段が検知した磁束密度分布波形に略相似形の電流を駆動コイルに流すことにより、誘起電圧波形と電流波形が略相似となるので、トルクリップルおよびトルク変化率を一層低く抑えることができるとともに、モータ効率が大幅に向上するため、低騒音化、高効率化を実現した交流電源直結型のブラシレスＤＣモータが得られる。
【００５５】
また、電圧設定手段を露出して設けることにより、低圧直流電圧の値が任意に変更できることから、複数段の速度調節が可能となるとともに、モータが機器に搭載された後であっても、その機器の性能の調整を容易にできる交流電源直結型のブラシレスＤＣモータが得られ、電気機器においては、性能調整が都度対応できることから標準化ができることとなる。
【００５６】
また、電流検出手段によってスイッチング素子に流れる平均電流値を検知し、供給電流値制御手段がスイッチング素子に供給する平均電流を略一定に制御するので、出力トルクが略一定運転となり、負荷変化に対する回転数差が大きくなるため、シロッコファンなど遠心型の送風機を搭載した換気装置等の電気機器においては、最大静圧時の回転数と静圧ゼロ時の回転数差が誘導電動機を搭載した場合と同等になるので、最大静圧が極端に低くなることや、静圧ゼロ時の風量が極端に多くなることを防止できるとともに、静音化、低消費電力化を実現できる。
【００５７】
また、電流設定手段を露出して設けることにより、供給電流値が任意に変更できることから、複数段の速度調節が可能となるとともに、モータが機器に搭載された後であっても、その機器の性能の調整を容易にできる交流電源直結型のブラシレスＤＣモータが得られ、電気機器においては、性能調整が都度対応できることから標準化ができることとなる。
【００５８】
また、スイッチング素子に供給する平均電力を略一定に制御する供給電力制御手段を備えることにより、モータにかかる負荷が軽くなるにしたがって供給電流が低くなるため、それに応じて印加電圧を高くすることになり、逆に負荷が重くなれば供給電流が高くなるので、印加電圧を低くするため、負荷変化に対する回転数差が大きくなることとなり、シロッコファンなど遠心型の送風機に搭載しても、最大静圧時の回転数と静圧ゼロ時の回転数差が誘導電動機を搭載した場合と同等になるので、最大静圧が極端に低くなることや、静圧ゼロ時の風量が極端に多くなることを防止できるとともに、負荷変動に対して消費電力の変化がなく、静音化、低消費電力化を実現できる。
【００５９】
また、電力設定手段を露出して設けることにより、電力が任意に変更できることから、複数段の速度調節が可能となるとともに、モータが機器に搭載された後であっても、その機器の性能の調整を容易にできる交流電源直結型のブラシレスＤＣモータが得られ、電気機器においては、性能調整が都度対応できることから標準化ができることとなる。
【００６０】
また、磁束密度分布波形合成手段が、磁束密度分布検知手段が検知した２相分の波形を合成することにより、各相の磁束密度分布検知手段のばらつきの影響が小さくなるとともに、各相の磁束密度分布波形は、基本的には位相が単にずれただけの波形であることから、２相を減算合成することにより、検知した磁束密度分布波形に含まれた高調波成分が除去されるので、回転むらの発生が抑制できるとともに、トルクリップルおよびトルク変化率をさらに低く抑えることができるため、高品質化を実現した交流電源直結型のブラシレスＤＣモータおよびそのブラシレスＤＣモータを搭載した電気機器が得られる。
【００６１】
また、ＰＷＭ制御することによって、電流波形を形成する駆動ロジック制御手段にすることにより、スイッチング素子の発熱を抑制できるので、使用可能な負荷トルクの範囲がさらに広くできる交流電源直結型のブラシレスＤＣモータおよびそのブラシレスＤＣモータを搭載した電気機器が得られる。
【００６２】
また、磁石回転子の永久磁石を極異方性磁石とすることにより、誘起電圧波形も電流波形もともに正弦波となることから、トルクリップルおよびトルク変化率をより一層低く抑えることができるとともに、モータ効率も大幅に向上するので、静音化、高効率化を実現した交流電源直結型のブラシレスＤＣモータおよびそのブラシレスＤＣモータを搭載した電気機器が得られる。
【図面の簡単な説明】
【図１】本発明の実施例１における交流電源直結型ブラシレスＤＣモータを示す断面図
【図２】同ブラシレスＤＣモータを示すブロック図
【図３】同ブラシレスＤＣモータの整流後の電圧波形を示す図
【図４】同ブラシレスＤＣモータにおいて他の構成を示すブロック図
【図５】本発明の実施例２における交流電源直結型ブラシレスＤＣモータを示すブロック図
【図６】同ブラシレスＤＣモータを示す断面図
【図７】同ブラシレスＤＣモータを搭載した換気装置を示す断面図
【図８】同ブラシレスＤＣモータにおいて他の構成を示すブロック図
【図９】従来のＤＣモータを示す回路図
【図１０】同ＤＣモータを示す断面図
【図１１】同ＤＣモータを示す斜視図
【図１２】同ＤＣモータと誘導電動機のトルク−回転数特性を比較するグラフ
【符号の説明】
１ブラシレスＤＣモータ
２駆動コイル
３磁石回転子
４磁束密度分布検知手段
５駆動ロジック制御手段
６スイッチング素子
７電流波形制御手段
８低圧直流電圧変換手段
９整流手段
１０固定子
１０ａ固定子鉄心
１１インシュレータ
１２磁束密度分布波形合成手段
１３電圧設定手段
１４低圧直流電圧値変更手段
１５交流電源接続手段
１６ワンチップＩＣ
１７ブラケット
１８平滑コンデンサ
１９シャフト
２０軸受け
２１熱硬化性樹脂
２２プリント基板
２３生成電圧指示手段
２４凹部
２５電流設定手段
２６電流検出手段
２７供給電流値制御手段
２８供給電流値変更手段
２９ブラシレスＤＣモータ
３０ワンチップＩＣ
３１換気装置
３２電力設定手段
３３供給電力制御手段
３４供給電力変更手段
３５ブラシレスＤＣモータ[0001]
BACKGROUND OF THE INVENTION
The present invention mainly includes a ventilation device for exhaust and supply of air such as a pipe fan and a ceiling-embedded type, a brushless DC motor for driving a fan of a blower, a humidifier, a dehumidifier, a refrigeration device, and the brushless DC motor thereof. It relates to the electrical equipment installed.
[0002]
[Prior art]
In recent years, there has been a strong demand for low-price, high-efficiency, and low-noise performance in fan-driven motors mounted on electrical equipment such as ventilators, and it is difficult to achieve significant increases in efficiency with induction motors. The number of brushless DC motors using permanent magnets is increasing. On the other hand, there is also a demand for an electric motor that is easy to use, such as simply rotating by connecting to an AC power source.
[0003]
Conventionally, the thing of the structure disclosed by patent documents 1-3 is known for this kind of electric motor.
[0004]
Hereinafter, the electric motor will be described with reference to FIGS.
[0005]
As shown in the figure, a rectifier 51 that rectifies commercial AC power on a single printed circuit board 56, two-phase drive coils 53 and 54 of a DC motor, and a magnet rotor 55 provided with permanent magnets 55a, Between the motor drive coils 53 and 54 and the rectifying unit 51, a large-capacity electrolytic capacitor is arranged as a smoothing capacitor 59, and switching elements 57 and 58 that allow current to flow in the motor drive coils 53 and 54 only in one direction, and this switching Including the elements 57 and 58, and a control unit 52 that controls energization of the motor drive coils 53 and 54, and directly supplies the high-voltage DC power source rectified by the rectification unit 51 to the motor drive coils 53 and 54. The high-voltage DC power source rectified by the rectifying unit 51 is reduced in pressure and supplied to the control unit 52.
[0006]
[Patent Document 1]
JP 2000-41370 A
[Patent Document 2]
JP 2000-41395 A
[Patent Document 3]
Japanese Patent Laid-Open No. 2002-10609
[0007]
[Problems to be solved by the invention]
According to such a conventional electric motor, since it is a two-phase half-wave drive system, in order to prevent the occurrence of dead center, countermeasures by superimposing spatial harmonic torque and the interval between stator teeth are changed. Even if countermeasures are taken, there is a problem that the torque ripple and torque change rate will increase, so noise and vibration will increase and noise reduction will not be possible, and the torque ripple and torque change rate will be reduced to reduce noise and vibration. Is required to do.
[0008]
In addition, since it is a half-wave drive system, the current increases and the current change with respect to the load torque also increases, so there is a problem that the range of usable load torque is narrowed, and the current can be reduced and usable. A wide range of load torque is required.
[0009]
In addition, since it is a half-wave drive system, copper loss becomes extremely large in high output areas, and there is a problem that the effect of reducing power consumption for induction motors is lost. Even so, it is required to realize low power consumption.
[0010]
In addition, since the high-voltage DC voltage obtained at the rectifier is directly used as the drive power supply, it is necessary to increase the capacity of the smoothing capacitor after the rectifier in order to obtain a stable high-voltage DC voltage. Therefore, there is a problem that the circuit cannot be downsized, the stability of quality can be ensured, and the life cannot be extended. When the smoothing capacitor has a small capacity, the power ripple will increase, resulting in an extremely large torque ripple, further vibration and noise, and excessive rotation unevenness. However, there is a problem that the air volume varies and a stable air flow cannot be secured, and it is required that a stable air flow can be secured after realizing miniaturization, high quality, and long life of the circuit.
[0011]
In addition, in order to use an electric motor in a higher output region, it is necessary to increase the heat dissipation effect of the heat generating component by molding the heat generating component such as a switching element integrally with a resin. When an electrolytic capacitor is used, due to the structural characteristics of the electrolytic capacitor, there is a possibility of an increase in leakage current due to leakage of the electrolyte and the damage of the aluminum element during molding. Has problems in terms of quality, such as the possibility of rupture of the aluminum case due to the inhibition of the diffusion of hydrogen gas generated in the chemical reaction of the electrolyte, and has a certain life due to the consumption of the electrolyte In addition to ensuring the quality during manufacturing and actual use, it is possible to increase the output even further by enabling resin molding including heat-generating parts. It has been required to be able to enable the use of the area.
[0012]
The present invention solves such a conventional problem, can reduce torque ripple and torque change rate, suppress the generation of noise and vibration, reduce current, and can be used. A brushless DC motor with a direct connection to an AC power source that has a wide torque range, can achieve low power consumption even in a high output range, and can reduce the size of the circuit, improve quality, and prolong its service life, while also suppressing the occurrence of uneven rotation. The purpose is to provide.
[0013]
And since the speed cannot be adjusted, only the forced ventilation mode in the ventilator or the constant ventilation mode with a small air volume can be supported, so there is a problem that it is difficult to mount on the ventilator, and the speed can be adjusted. It is requested.
[0014]
An object of the present invention is to solve such a conventional problem and to provide a brushless DC motor directly connected to an AC power source capable of arbitrarily adjusting the speed.
[0015]
Furthermore, equipment with a built-in centrifugal fan such as a sirocco fan such as a duct type ventilation device is equipped with an induction motor and used in a region where the rotational speed change from the starting torque to the maximum torque is large in its torque characteristics. Most of the devices are installed. When a brushless DC motor is mounted on such a blower and it is operated at a constant applied voltage, as shown in the torque-rotational speed characteristic comparison graph of FIG. Since the difference between the rotation speed and the rotation speed at zero static pressure is extremely small compared to the induction motor, the maximum static pressure value is equivalent to the value when the induction motor is installed. However, there is a problem that the air volume at zero static pressure becomes extremely large, noise and vibration increase, and the effect of reducing power consumption including cooling and heating energy loss is reduced. If the volume is made equal, the maximum static pressure value will be extremely low, and there will be a problem that the air volume will fluctuate greatly due to changes in external pressure loss due to outside wind, etc., which is the same as when an induction motor is installed. It is required that air flow-static pressure characteristics be obtained.
[0016]
The present invention solves such a conventional problem, and an object thereof is to provide an AC power supply directly connected brushless DC motor capable of obtaining an air volume-static pressure characteristic equivalent to that when an induction motor is mounted. It is said.
[0017]
[Means for Solving the Problems]
In order to achieve the above object, the brushless DC motor of the present invention has a drive logic control means for sequentially energizing a drive coil in a predetermined direction and order, a rectifying means for full-wave rectification of an AC power supply, and this rectification. A plurality of low voltage DC voltage conversion means for converting the high voltage obtained by the means into a low voltage DC voltage, and a plurality of low voltage DC voltages generated by the low voltage DC voltage conversion means based on the output of the drive logic control means. Switching element, low-voltage DC voltage value changing means for changing the value of the low-voltage DC voltage generated by the low-voltage DC voltage conversion means, and an average current supplied to the switching element by controlling the low-voltage DC voltage value changing means Almost constant To control the output torque to be almost constant. A current detection means for detecting a current supplied to the switching element, and a current setting means for setting a current value controlled by the supply current value control means. The AC power source direct connection type brushless DC motor is characterized in that the means is exposed.
[0018]
According to the present invention, the supply current value control means and the exposed current setting means provide a substantially constant operation with an arbitrarily set torque, and the rotational speed difference with respect to the load change becomes large. Even if it is mounted on a blower of the type, the difference between the number of rotations at maximum static pressure and the number of rotations at zero static pressure is the same as when an induction motor is installed. Directly connected to an AC power source that can prevent an excessive increase in the air flow at zero pressure, achieve noise reduction and low power consumption, and can set any number of air flow-static pressure characteristics equivalent to those equipped with an induction motor A brushless DC motor and electrical device of the type are obtained.
[0019]
Another means is to sequentially energize the drive coil in a predetermined direction and in order based on the magnetic flux density distribution detecting means for detecting the magnetic flux density distribution of the magnet rotor and the signal of the magnetic flux density distribution detecting means. Drive logic control means, rectifying means for full-wave rectification of the AC power supply, and low voltage DC voltage converting means for converting a high voltage obtained by the rectifying means into a low voltage DC voltage, the magnetic flux density distribution detecting means detecting The magnetic flux density distribution waveform is arranged so that it is substantially similar to the induced voltage waveform induced in the drive coil as the magnet rotor rotates, and the drive logic control means includes the magnetic flux density distribution detection means. Current waveform control means for causing a current substantially similar to the detected waveform to flow through the drive coil is provided, and generated by the low-voltage DC voltage conversion means based on an instruction from the current waveform control means. A plurality of switching elements for supplying a low-voltage DC voltage to the drive coil, a low-voltage DC voltage value changing means for changing the value of the low-voltage DC voltage generated by the low-voltage DC voltage conversion means, and the low-voltage DC voltage value changing means To control the average current supplied to the switching element to be substantially constant. To control the output torque to be almost constant. A current detection means for detecting a current supplied to the switching element, and a current setting means for setting a current value controlled by the supply current value control means. The AC power source direct connection type brushless DC motor is characterized in that the means is exposed.
[0020]
According to the present invention, since the induced voltage waveform and the current waveform are substantially similar, the torque ripple and torque change rate are reduced, noise and vibration are suppressed, and the efficiency of the brushless DC motor is greatly improved. Therefore, the range of the load torque that can be used is widened, and the copper loss can be reduced, so that an AC power supply directly connected brushless DC motor and an electric device that can realize low power consumption can be obtained. Furthermore, since a low-voltage DC voltage is supplied to the drive coil, the capacity of the smoothing capacitor used in the subsequent stage of the full-wave rectifier circuit can be kept low, so that no electrolytic capacitor is required and the circuit is greatly reduced in size. High quality, long service life, and rotation unevenness can be suppressed, and the supply current value control means and the exposed current setting means enable almost constant operation at an arbitrarily set torque. Therefore, even if it is installed in a centrifugal blower such as a sirocco fan, the difference between the number of rotations at maximum static pressure and the number of rotations at zero static pressure is the same as when an induction motor is installed. Can be prevented from becoming extremely low and the air volume at zero static pressure can be prevented from becoming excessively high, as well as being able to achieve low noise and low power consumption, equivalent to the case where an induction motor is installed. Air volume - the brushless DC motor and electrical equipment of the AC power source directly coupled to the static pressure characteristics can be arbitrarily and many settings are obtained.
[0021]
Another means is to sequentially energize the drive coil in a predetermined direction and in order based on the magnetic flux density distribution detecting means for detecting the magnetic flux density distribution of the magnet rotor and the signal of the magnetic flux density distribution detecting means. Drive logic control means, rectifying means for full-wave rectification of the AC power supply, and low voltage DC voltage converting means for converting a high voltage obtained by the rectifying means into a low voltage DC voltage, the magnetic flux density distribution detecting means detecting The magnetic flux density distribution waveform is arranged so that it is substantially similar to the induced voltage waveform induced in the drive coil as the magnet rotor rotates, and the drive logic control means includes the magnetic flux density distribution detection means. Current waveform control means for causing a current substantially similar to the detected waveform to flow through the drive coil is provided, and generated by the low-voltage DC voltage conversion means based on an instruction from the current waveform control means. A plurality of switching elements for supplying a low-voltage DC voltage to the drive coil, a low-voltage DC voltage value changing means for changing the value of the low-voltage DC voltage generated by the low-voltage DC voltage conversion means, and the low-voltage DC voltage value changing means Power supply value control means for controlling the average power supplied to the switching element by controlling the power supply, and comprising power setting means for setting a power value controlled by the supply power control means. The AC power source direct connection type brushless DC motor is characterized in that the means is exposed.
[0022]
According to the present invention, since the induced voltage waveform and the current waveform are substantially similar, the torque ripple and torque change rate are reduced, noise and vibration are suppressed, and the efficiency of the brushless DC motor is greatly improved. Therefore, the range of the load torque that can be used is widened, and the copper loss can be reduced, so that an AC power supply directly connected brushless DC motor and an electric device that can realize low power consumption can be obtained. Furthermore, since a low-voltage DC voltage is supplied to the drive coil, the capacity of the smoothing capacitor used in the subsequent stage of the full-wave rectifier circuit can be kept low, so that no electrolytic capacitor is required and the circuit is greatly reduced in size. High quality, long life, and uneven rotation can be suppressed, and the supply power control means and the exposed power setting means reduce the current and increase the applied voltage as the load becomes lighter. As a result, the difference in rotational speed with respect to load changes becomes large, and even if it is installed in a centrifugal blower such as a sirocco fan, the difference between the rotational speed at the maximum static pressure and the rotational speed at zero static pressure is installed in the induction motor. Therefore, it is possible to prevent the maximum static pressure from becoming extremely low and the air volume at zero static pressure from being excessively increased, and to achieve low noise and low power consumption. It can, when provided with the induction motor equivalent air volume - of the AC power source directly coupled to the static pressure characteristics can be arbitrarily and many settings brushless DC motors and electrical equipment are obtained.
[0023]
Another means is provided with a magnetic flux density distribution waveform synthesizing means for synthesizing two phases of the waveforms detected by the magnetic flux density distribution detecting means, and the drive logic control means is a waveform synthesized by the magnetic flux density distribution waveform synthesizing means. The configuration of the brushless DC motor with direct connection to an AC power source is characterized in that a substantially similar current is passed through the drive coil.
[0024]
According to the present invention, since harmonic components such as third-order harmonics and fifth-order harmonics in current waveforms can be removed, alternating current capable of reducing noise and vibration while suppressing the inclusion of harmonic components in instantaneous torque. A brushless DC motor and electrical equipment directly connected to the power source can be obtained.
[0025]
Another means is a configuration of a brushless DC motor having a direct connection to an AC power source characterized in that a current waveform is formed by PWM control.
[0026]
According to the present invention, since the heat generation of the switching element can be suppressed, a brushless DC motor and an electric device directly connected to an AC power source that can further widen the range of usable load torque can be obtained.
[0027]
Another means is a configuration of a brushless DC motor directly connected to an AC power source, wherein the permanent magnet of the magnet rotor is a polar anisotropic magnet.
[0028]
According to the present invention, since the induced voltage waveform and the current waveform are substantially sine waves, the torque ripple and the torque change rate are further reduced, and noise and vibration can be further reduced and noise and vibration can be reduced. A brushless DC motor and an electric device directly connected to a possible AC power source can be obtained.
[0029]
DETAILED DESCRIPTION OF THE INVENTION
According to the first aspect of the present invention, there is provided a drive logic control means for sequentially energizing a drive coil in a predetermined direction and order, a rectifying means for full-wave rectifying an AC power supply, and a high voltage obtained by the rectifying means. Low voltage direct current voltage conversion means for converting the low voltage direct current voltage into the low voltage direct current voltage conversion means, a plurality of switching elements for supplying the drive coil with the low voltage direct current voltage generated by the low voltage direct current voltage conversion means based on the output of the drive logic control means, Low voltage DC voltage value changing means for changing the value of the low voltage DC voltage generated by the low voltage DC voltage converting means, and controlling the low voltage DC voltage value changing means to control the average current supplied to the switching element to be substantially constant. To control the output torque to be almost constant. A current detection means for detecting a current supplied to the switching element, and a current setting means for setting a current value controlled by the supply current value control means. The AC power supply direct-coupled brushless DC motor is characterized in that the means is exposed and provided with a torque set arbitrarily by the supply current value control means and the exposed current setting means. It has the effect that the operation is substantially constant.
[0030]
According to the second aspect of the present invention, the magnetic flux density distribution detecting means for detecting the magnetic flux density distribution of the magnet rotor, and all the waves are sequentially applied to the drive coil in a predetermined direction and order based on the signal of the magnetic flux density distribution detecting means. A drive logic control means for energizing, a rectifying means for full-wave rectification of an AC power supply, and a low-voltage DC voltage conversion means for converting a high voltage obtained by the rectification means into a low-voltage DC voltage, and detecting the magnetic flux density distribution The means is arranged so that the detected magnetic flux density distribution waveform is substantially similar to the induced voltage waveform induced in the drive coil as the magnet rotor rotates, and the magnetic flux density distribution is provided in the drive logic control means. Current waveform control means is provided for flowing a current substantially similar to the waveform detected by the detection means to the drive coil, and the low-voltage DC voltage conversion means is configured to operate based on an instruction from the current waveform control means. A plurality of switching elements for supplying the generated low-voltage DC voltage to the drive coil, low-voltage DC voltage value changing means for changing the value of the low-voltage DC voltage generated by the low-voltage DC voltage conversion means, and the low-voltage DC voltage value By controlling the changing means, the average current supplied to the switching element is controlled to be substantially constant. To control the output torque to be almost constant. A current detection means for detecting a current supplied to the switching element, and a current setting means for setting a current value controlled by the supply current value control means. The AC power supply direct-coupled brushless DC motor is characterized in that the means are exposed, and the induced voltage waveform and the current waveform are substantially similar, so the torque ripple and torque change rate are small. In addition, the efficiency can be greatly improved, and the low-voltage DC voltage is supplied to the drive coil, so that the capacity of the smoothing capacitor used in the subsequent stage of the full-wave rectifier circuit can be kept low, and the supply current value control By the means and the exposed current setting means, there is an effect that the operation becomes substantially constant at an arbitrarily set torque.
[0031]
Claim 3 According to the invention described in the above, the magnetic flux density distribution detecting means for detecting the magnetic flux density distribution of the magnet rotor, and the full-wave energization sequentially in a predetermined direction and order based on the signal of the magnetic flux density distribution detecting means. Drive logic control means, rectifying means for full-wave rectification of the AC power supply, and low voltage DC voltage converting means for converting a high voltage obtained by the rectifying means into a low voltage DC voltage, the magnetic flux density distribution detecting means detecting The magnetic flux density distribution waveform is arranged so that it is substantially similar to the induced voltage waveform induced in the drive coil as the magnet rotor rotates, and the drive logic control means includes the magnetic flux density distribution detection means. Current waveform control means for causing a current substantially similar to the detected waveform to flow through the drive coil is provided, and generated by the low-voltage DC voltage conversion means based on an instruction from the current waveform control means. A plurality of switching elements for supplying a low-voltage DC voltage to the drive coil, a low-voltage DC voltage value changing means for changing the value of the low-voltage DC voltage generated by the low-voltage DC voltage conversion means, and the low-voltage DC voltage value changing means Power supply value control means for controlling the average power supplied to the switching element by controlling the power supply, and comprising power setting means for setting a power value controlled by the supply power control means. The AC power supply direct-coupled brushless DC motor is characterized in that the means are exposed, and the induced voltage waveform and the current waveform are substantially similar, so the torque ripple and torque change rate are small. In addition, the efficiency can be greatly improved and a low-voltage DC voltage is supplied to the drive coil. With an effect that it is possible to suppress the capacity of the capacitor, such an action by the power setting unit exposed the supply power control means, the load current is lowered in accordance becomes lighter, increasing the applied voltage.
[0032]
Claim 4 The invention according to claim 2 further includes magnetic flux density distribution waveform synthesizing means for synthesizing two phases of the waveforms detected by the magnetic flux density distribution detecting means. 3 The drive logic control means described above is used as a drive logic control means for causing a current substantially similar to the waveform synthesized by the magnetic flux density distribution waveform synthesis means to flow through the drive coil, so that a third harmonic or a fifth harmonic in the current waveform can be obtained. Harmonic components such as waves can be removed.
[0033]
Claim 5 The invention described in claim 2, in particular, 3 By performing PWM control of the mounted drive logic control means, the drive logic control means for forming a current waveform has the effect that heat generation of the switching element can be suppressed.
[0034]
Claim 6 The invention described in claim 2, in particular, 3 By making the permanent magnet of the mounted magnet rotor into a polar anisotropic magnet, the induced voltage waveform and the current waveform become substantially sine waves, so that the torque ripple and the torque change rate are further reduced.
[0035]
Embodiments of the present invention will be described below with reference to FIGS.
[0036]
【Example】
(Example 1)
As shown in FIGS. 1 to 3, reference numeral 1 denotes a brushless DC motor directly connected to an AC power source, and 10 denotes a drive coil 2 via an insulator 11 formed of an insulating material on a stator core 10a having a plurality of slots. In the wound stator, the stator 10 is molded with a thermosetting resin 21 to form a jacket, and 17 is a bracket that holds the bearing 20. Reference numeral 3 denotes a magnet rotor, which is formed by integrally orienting a plastic magnet with the shaft 19 during the injection molding, and the main magnetic pole portion is a polar anisotropic magnet 3a. Reference numeral 22 denotes a printed circuit board on which electronic components and the like are mounted and soldered. A part of the jacket formed of the thermosetting resin 21 is provided with a recess 24 that reaches the printed circuit board 22. A hall element 4 serves as a magnetic flux density distribution detecting means for detecting the magnetic flux density distribution of the polar anisotropic magnet 3a. The waveform detected by the hall element 4 is induced in the drive coil 2 by the polar anisotropic magnet 3a. The gap between the Hall element 4 and the polar anisotropic magnet 3a is set and arranged so as to be substantially similar to the voltage waveform. A magnetic flux density distribution waveform synthesizing unit 12 subtracts the v-phase waveform from the u-phase waveform of the Hall element 4 in order to remove the harmonic component of the current waveform supplied to the u-phase of the drive coil 2, and similarly the drive coil. For the v phase of 2, the w phase waveform is subtracted from the v phase waveform of the Hall element 4, and for the w phase of the drive coil, the u phase waveform is subtracted from the w phase waveform of the Hall element 4. Reference numeral 5 denotes drive logic control means for controlling ON / OFF of the switching elements so that the drive coil 2 is sequentially full-wave energized in a predetermined direction and order. The current waveform control means 7 is controlled by the magnetic flux density distribution waveform synthesis means 12. The output bias current is adjusted while performing feedback so that the switching element 6 is in a non-saturated state close to saturation so that the waveform is substantially similar to the waveform from which the wave component is removed. 15 is an AC power supply connecting means for connecting a commercial AC power supply, 9 is a rectifying means for full-wave rectification of the AC power supply, and 8 is a high voltage having a ripple that has been full-wave rectified by the rectifying means 9 to 45 V or less. The low-voltage DC voltage conversion means for converting into a substantially flat low-voltage DC voltage is supplied to the drive coil 2 through the switching element 6 and the drive logic is controlled. Also supplied as control power to the means 5 and the like. Between the low-voltage DC voltage converting means 8 and the rectifying means 9, a small-capacity smoothing capacitor 18 is arranged to compensate for a voltage of 2.1 milliseconds, which is 45V or less when full-wave rectification is performed on AC 100V50Hz. Yes. Reference numeral 13 denotes voltage setting means, which is exposed in the recess 24. Reference numeral 23 denotes generated voltage indicating means for instructing a low-voltage DC voltage value generated by the low-voltage DC voltage converting means 8 based on a ratio between the voltage generated by the low-voltage DC voltage converting means 8 and the voltage output by the voltage setting means 13. And 14 is a low-voltage DC voltage value changing means for changing the low-voltage DC voltage value generated by the low-voltage DC voltage conversion means 8 in accordance with an instruction from the generated voltage instruction means 23. 1 is mounted on an alumina substrate except for a choke coil and a secondary smoothing capacitor which are one of the components constituting the low-voltage DC voltage conversion means 8 among the electronic components surrounded by a one-dot chain line in FIG. In this configuration, the wiring connection and the one-chip IC 16 are formed by protective coating with a phenolic resin.
[0037]
According to the brushless DC motor 1 directly connected to the AC power source of the present invention, the high voltage having ripples rectified by the rectifying means 9 for full-wave rectification is converted into a substantially flat voltage whose low voltage DC voltage converting means 8 is 45 V or less. By converting the voltage into a low-voltage DC voltage and supplying it to the drive coil 2 as a drive power supply, the smoothing capacitor 18 after full-wave rectification has a very short period of time when the voltage is insufficient (for example, 2.1 milliseconds for AC100V50Hz). Capacitance can be kept as low as possible, so the capacitor can be reduced in size and space can be saved, and there is no change in temperature characteristics because ceramic capacitors and film capacitors can be used without using electrolytic capacitors. High quality, long life and drastic downsizing, including no leakage of electrolyte, no depletion, etc. Since the body to it is possible to resin molding, the AC power source directly connected brushless DC motor can be obtained more becomes possible further use in high output region.
[0038]
In addition, the value of the low-voltage DC voltage can be arbitrarily changed by the voltage setting means 13 provided in an exposed manner, so that it is possible to adjust the speed of a plurality of stages and even after the motor is mounted on the device. Since adjustment of the performance of the device can be easily performed as needed, an AC power supply directly connected brushless DC motor that can contribute to standardization of the motor-equipped device is obtained.
[0039]
Further, even if the capacity of the smoothing capacitor 18 is small, the low-voltage DC voltage conversion means 8 generates a substantially flat low-voltage DC voltage, so that a brushless DC motor directly connected to an AC power source with reduced torque ripple and rotation unevenness can be obtained. And since rotation is stabilized even if it uses for a fan drive, stabilization of ventilation volume is realizable.
[0040]
In addition, since the driving logic control means 5 performs three-phase full-wave driving, there is no need to consider the dead point, torque ripple and torque change rate can be reduced, driving current can be reduced, and copper in a high output region can be reduced. Since the loss can be reduced, it is possible to obtain a brushless DC motor directly connected to an AC power source that suppresses the generation of noise and vibration, has a wide range of usable load torque, and can realize low power consumption even in a high output region.
[0041]
Further, the gap between the magnetic flux density distribution detecting means 4 and the magnet is set so that the waveform detected by the magnetic flux density distribution detecting means 4 is substantially similar to the induced voltage waveform induced in the drive coil 2 by the polar anisotropic magnet 3a. The current waveform control means 7 causes the induced voltage waveform and the current waveform to be substantially similar by passing a current substantially similar to the magnetic flux density distribution waveform detected by the magnetic flux density distribution detection means 4 to the drive coil 2. The torque ripple and the rate of change in torque can be further reduced, and the motor efficiency is greatly improved. Therefore, a brushless DC motor directly connected to an AC power source that achieves low noise and high efficiency can be obtained.
[0042]
Further, by making the main magnetic pole portion of the magnet rotor 3 the polar anisotropic magnet 3a, both the induced voltage waveform and the current waveform become sinusoidal waves, so that the torque ripple and the torque change rate can be further reduced. In addition, since the motor efficiency is greatly improved, it is possible to obtain a brushless DC motor directly connected to an AC power source that achieves low noise and high efficiency.
[0043]
Further, the magnetic flux density distribution waveform synthesizing unit 12 synthesizes the u-phase, v-phase, and w-phase waveforms detected by the magnetic flux density distribution detection unit 4, so that the influence of variations in the magnetic flux density distribution detection unit 4 of each phase is affected. As the magnetic flux density distribution waveform of each of the u-phase, v-phase, and w-phase is basically a waveform that is simply shifted in phase, the detected magnetic flux is obtained by subtracting and synthesizing the two phases. Since harmonic components contained in the density distribution waveform are removed, rotation irregularity can be suppressed, and torque ripple and torque change rate can be further reduced. The brushless DC motor is obtained.
[0044]
In the first embodiment, the current waveform supplied to the drive coil 2 is configured to be substantially similar to the induced voltage waveform. However, a 120-degree rectangular wave is used depending on the use and the noise level required for the product. A wide-angle energization method such as energization or 140-degree or 150-degree energization is also possible. By supplying a low-voltage DC voltage to the drive coil 2 as a drive power supply, the capacity of the smoothing capacitor after full-wave rectification is kept low, and rotation unevenness By reducing copper loss in the high output area, it achieves significant downsizing, high quality, long life, wide range of usable load torque, and low power consumption even in the high output area There is no difference in that a brushless DC motor that can be directly connected to an AC power supply can be obtained.
[0045]
In the first embodiment, the magnetic flux density distribution detecting means 4 is used. However, an induced voltage or current induced in the non-energized phase may be detected to determine the energized phase for the magnet rotor, There is no difference in the effect.
[0046]
In the first embodiment, the output bias current is adjusted while performing feedback so that the switching element 6 is in a non-saturated state close to saturation. However, the switching element 6 may be PWM controlled to control the current waveform. In this case, since the loss of the switching element 6 can be reduced, the heat generation of the switching element 6 is suppressed, and a brushless DC motor directly connected to an AC power source that can further widen the range of usable load torque can be obtained.
[0047]
In the first embodiment, the low-voltage DC voltage converting means 8 converts the voltage to a substantially flat low-voltage DC voltage of 45V or less. However, if the voltage is converted to a low-voltage DC voltage of 36V or less, it only compensates for a period of 1.7 milliseconds. Therefore, the capacitance of the capacitor can be further reduced.
[0048]
In the first embodiment, the low-voltage DC voltage conversion means 8 is supplied to the low-voltage DC voltage conversion means 8 according to the ratio of the voltage generated by the low-voltage DC voltage conversion means 8 to the voltage output from the voltage setting means 13. Generated voltage indicating means 23 for instructing the low voltage DC voltage value to be generated, and low voltage DC voltage value changing means for changing the low voltage DC voltage value generated by the low voltage DC voltage converting means 8 according to the instruction of the generated voltage instruction means 23 In the brushless DC motor having a low output, as shown in FIG. 4, the low voltage DC voltage output from the low voltage DC voltage converting means 8 is stepped down by a resistance voltage dividing circuit or the like. The step-down DC voltage may be supplied to the switching element, and there is no difference in the operation and effect.
(Example 2)
As shown in FIGS. 5 to 7, reference numeral 31 denotes a ceiling-embedded ventilation fan, which is a type of ventilation device, and is mounted with a brushless DC motor 29 directly connected to an AC power source for driving the fan. Reference numeral 26 denotes current detection means for detecting the current supplied to the switching element 6, and reference numeral 27 denotes supply current value control means. The supply current value control means 27 controls the low-voltage DC voltage value changing means 14 so that the average current value supplied to the switching element 6 detected by the current detection means 26 is equal to the set current value. Thus, feedback control is performed while varying the voltage output from the low-voltage DC voltage conversion means 8. Reference numeral 25 denotes current setting means. The low-voltage DC voltage generated by the low-voltage DC voltage conversion means 8 is reduced by a resistance voltage dividing circuit or the like to be converted into a supply current value indicating voltage, and is exposed to the recess 24. . Reference numeral 28 denotes supply current value changing means. The supply current value control means 27 is substantially constant according to the ratio of the low-voltage DC voltage generated by the low-voltage DC voltage conversion means 8 and the low-voltage DC voltage generated by the current setting means 25. The average current value to be controlled is determined. 5 is mounted on an alumina substrate except for the choke coil and the secondary smoothing capacitor which are one of the components constituting the low-voltage DC voltage conversion means 8 among the electronic components surrounded by the one-dot chain line in FIG. In this configuration, the same parts as those of the first embodiment are denoted by the same reference numerals and detailed description is omitted. .
[0049]
According to the brushless DC motor 29 directly connected to the AC power source of the present invention as described above, the supply current value control means 27 controls the average current supplied to the switching element 6 so that the output torque is substantially constant, Since the rotational speed difference with respect to load changes becomes large, in the ventilator 31 equipped with a centrifugal blower such as a sirocco fan, when the induction motor is equipped with a rotational speed difference between the maximum static pressure and zero static pressure Therefore, it is possible to prevent the maximum static pressure from becoming extremely low and the air volume at the time of zero static pressure from being extremely increased, as well as to realize low noise and low power consumption.
[0050]
Further, the current setting means 25 is exposed so that the supply current value changing means 28 changes the average current value that is substantially constant controlled by the supply current value control means 27 in accordance with the voltage generated by the current setting means 25. As a result, it is possible to perform almost constant operation at any torque steplessly, and when installed in a centrifugal blower such as a sirocco fan, the same air volume-static pressure characteristics as when an induction motor is installed are set steplessly. An electric device such as a brushless DC motor 29 that can be directly connected to an AC power supply and a ventilator 31 equipped with the brushless DC motor 29 can be obtained. Furthermore, even after the motor is mounted on a device, an AC power supply directly connected brushless DC motor capable of easily adjusting the performance of the device can be obtained.
[0051]
In the second embodiment, the current supplied to the switching element 6 is controlled to be substantially constant. However, as shown in FIG. 8, the supply current value control means 27 is replaced with the supply power control means 33 to replace the supply current value. By replacing the changing means 28 with the power supply changing means 34 and replacing the current setting means 25 with the power setting means 32, the AC power supply direct-coupled brushless DC motor 35 is configured so that the load applied to the motor is reduced. The current decreases, the applied voltage is increased accordingly, and conversely, if the load is heavy, the supply current increases, so the applied voltage is decreased, so that the rotational speed difference with respect to the load change becomes large, Even if it is installed in a centrifugal blower such as a sirocco fan, the difference between the number of rotations at maximum static pressure and the number of rotations at zero static pressure is the same as when an induction motor is installed. Therefore, it is possible to prevent the maximum static pressure from becoming extremely low and the air volume at zero static pressure from being excessively increased, and there is no change in power consumption due to load fluctuations, resulting in quietness and low power consumption. Since this can be realized, an AC power supply directly connected brushless DC motor capable of setting the same air volume-static pressure characteristics as in the case where an induction motor is installed and an electric device equipped with the brushless DC motor can be obtained. Furthermore, even after the motor is mounted on the equipment, the performance of the equipment can be easily adjusted as necessary, so that a brushless DC motor directly connected to an AC power source that can contribute to the standardization of motor-mounted equipment is obtained. It is done.
[0052]
【The invention's effect】
As is clear from the above embodiments, according to the present invention, the high voltage having ripples rectified by the rectifying means for full wave rectification is converted into a substantially flat low voltage DC voltage by the low voltage DC voltage converting means of 45V or less. Then, by supplying the drive coil as a drive power supply, the smoothing capacitor after full-wave rectification should be kept low enough to compensate for a very short period of time when the voltage is insufficient (for example, 2.1 milliseconds for AC100V50Hz). Capacitors can be reduced in size and space, and ceramic capacitors and film capacitors can be used without using electrolytic capacitors, resulting in significant downsizing and no change in temperature characteristics. Brushless AC power supply direct connection type that can improve quality, extend the service life, and suppress torque ripple and rotation unevenness C motor can be obtained. And even if it uses for fan drive, stabilization of ventilation volume is realizable.
[0053]
In addition, since the driving logic control means performs three-phase full-wave driving, there is no need to consider dead points, torque ripple and torque change rate can be reduced, driving current can be reduced, and copper loss in a high output region can be reduced. Therefore, it is possible to obtain a brushless DC motor directly connected to an AC power source that suppresses the generation of noise and vibration, has a wide range of usable load torque, and can realize low power consumption even in a high output region.
[0054]
Further, the magnetic flux density distribution detecting means and the magnet gap are set and arranged so that the waveform detected by the magnetic flux density distribution detecting means is substantially similar to the induced voltage waveform induced in the drive coil by the magnet rotor, and the current waveform The control means causes a current similar to the magnetic flux density distribution waveform detected by the magnetic flux density distribution detection means to flow through the drive coil, so that the induced voltage waveform and the current waveform become substantially similar. Since it can be kept low and the motor efficiency is greatly improved, a brushless DC motor directly connected to an AC power source that achieves low noise and high efficiency can be obtained.
[0055]
Moreover, since the voltage setting means is exposed and provided, the value of the low-voltage DC voltage can be arbitrarily changed, so that it is possible to adjust the speed of a plurality of stages and even after the motor is mounted on the device. A brushless DC motor directly connected to an AC power source that can easily adjust the performance of the device can be obtained, and the electrical device can be standardized because the performance adjustment can be dealt with each time.
[0056]
Further, since the average current value flowing through the switching element is detected by the current detection means and the average current supplied to the switching element by the supply current value control means is controlled to be substantially constant, the output torque becomes substantially constant operation, and the rotation with respect to the load change Because the number difference becomes large, in the electrical equipment such as a ventilator equipped with a centrifugal blower such as a sirocco fan, the difference between the number of rotations at maximum static pressure and the number of rotations at zero static pressure Since they are equivalent, it is possible to prevent the maximum static pressure from becoming extremely low and the air volume at the time of zero static pressure from being extremely increased, as well as to achieve low noise and low power consumption.
[0057]
In addition, since the supply current value can be arbitrarily changed by providing the current setting means exposed, it is possible to adjust the speed in multiple stages, and even after the motor is mounted on the equipment, A brushless DC motor directly connected to an AC power source that can easily adjust the performance can be obtained, and the electrical equipment can be standardized because the performance adjustment can be made every time.
[0058]
Further, by providing a supply power control means for controlling the average power supplied to the switching element to be substantially constant, the supply current decreases as the load applied to the motor becomes lighter, so that the applied voltage is increased accordingly. On the other hand, since the supply current increases as the load becomes heavier, the applied voltage is reduced, and therefore the difference in rotational speed with respect to the load change becomes large. Even if it is mounted on a centrifugal blower such as a sirocco fan, the maximum static The difference between the number of rotations at the time of pressure and the number of rotations at the time of zero static pressure is the same as when an induction motor is installed, so that the maximum static pressure is extremely low and the air volume at zero static pressure is extremely large Can be prevented, and there is no change in power consumption with respect to load fluctuations.
[0059]
In addition, since the power can be changed arbitrarily by exposing the power setting means, it is possible to adjust the speed of multiple stages, and even after the motor is mounted on the equipment, the performance of the equipment can be adjusted. A brushless DC motor directly connected to an AC power source that can be easily adjusted can be obtained, and in electrical equipment, performance adjustment can be handled each time, so that standardization can be performed.
[0060]
Further, the magnetic flux density distribution waveform synthesizing means synthesizes the waveforms for two phases detected by the magnetic flux density distribution detecting means, thereby reducing the influence of variations in the magnetic flux density distribution detecting means of each phase and increasing the magnetic flux of each phase. Since the density distribution waveform is basically a waveform whose phase is merely shifted, the harmonic component contained in the detected magnetic flux density distribution waveform is removed by subtracting and synthesizing the two phases. Since the occurrence of uneven rotation can be suppressed and the torque ripple and torque change rate can be further reduced, a brushless DC motor directly connected to the AC power supply that achieves high quality and an electric device equipped with the brushless DC motor can be obtained. It is done.
[0061]
In addition, since it is possible to suppress the heat generation of the switching element by using the drive logic control means for forming a current waveform by PWM control, the AC power supply direct-coupled brushless DC motor that can further expand the range of usable load torque And the electric equipment carrying the brushless DC motor is obtained.
[0062]
In addition, by making the permanent magnet of the magnet rotor a polar anisotropic magnet, both the induced voltage waveform and the current waveform become sine waves, so that the torque ripple and the torque change rate can be further reduced, Since the motor efficiency is also greatly improved, a brushless DC motor directly connected to an AC power source that achieves low noise and high efficiency and an electric device equipped with the brushless DC motor can be obtained.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an AC power supply directly connected brushless DC motor according to Embodiment 1 of the present invention.
FIG. 2 is a block diagram showing the brushless DC motor.
FIG. 3 is a diagram showing a voltage waveform after rectification of the brushless DC motor.
FIG. 4 is a block diagram showing another configuration of the brushless DC motor.
FIG. 5 is a block diagram showing an AC power supply directly connected brushless DC motor according to a second embodiment of the present invention.
FIG. 6 is a sectional view showing the brushless DC motor.
FIG. 7 is a sectional view showing a ventilator equipped with the brushless DC motor.
FIG. 8 is a block diagram showing another configuration of the brushless DC motor.
FIG. 9 is a circuit diagram showing a conventional DC motor.
FIG. 10 is a sectional view showing the DC motor.
FIG. 11 is a perspective view showing the DC motor.
FIG. 12 is a graph comparing torque-rotational speed characteristics of the DC motor and the induction motor.
[Explanation of symbols]
1 Brushless DC motor
2 Drive coil
3 Magnet rotor
4 Magnetic flux density distribution detection means
5 Drive logic control means
6 Switching elements
7 Current waveform control means
8 Low voltage DC voltage conversion means
9 Rectification means
10 Stator
10a stator core
11 Insulator
12 Magnetic flux density distribution waveform synthesis means
13 Voltage setting means
14 Low voltage DC voltage value change means
15 AC power supply connection means
16 One-chip IC
17 Bracket
18 Smoothing capacitor
19 Shaft
20 Bearing
21 Thermosetting resin
22 Printed circuit board
23 Generated voltage instruction means
24 recess
25 Current setting means
26 Current detection means
27 Supply current value control means
28 Supply current value changing means
29 Brushless DC motor
30 One-chip IC
31 Ventilator
32 Power setting means
33 Supply power control means
34 Supply power changing means
35 Brushless DC motor

Claims

A brushless DC motor that is directly connected to an AC power source, in which a stator coil is wound with a drive coil via an insulator, a magnet rotor having a permanent magnet, and a magnetic pole position of the magnet rotor is detected. Magnetic pole position detecting means, a drive logic control means for sequentially energizing the drive coil in a predetermined direction and order based on a signal from the magnetic pole position detecting means, and rectification for full-wave rectification of the AC power supply Means, a low voltage DC voltage converting means for converting a high voltage obtained by the rectifying means into a low voltage DC voltage, and driving the low voltage DC voltage generated by the low voltage DC voltage converting means based on the output of the driving logic control means. A plurality of switching elements to be supplied to the coil, a low-voltage DC voltage value changing means for changing a value of the low-voltage DC voltage generated by the low-voltage DC voltage converting means, and the switch. Current detecting means for detecting a current supplied to the ring element, to control the substantially constant control to output torque average current supplied by controlling the low DC voltage value changing means to the switching element substantially constant AC power supply direct connection type characterized by comprising a current setting means for setting a current value controlled by the supply current value control means and exposing the current setting means Brushless DC motor.

A brushless DC motor that is directly connected to an AC power source, a stator having a stator core wound with a drive coil via an insulator, a magnet rotor having a permanent magnet, and a magnetic flux density distribution of the magnet rotor A magnetic flux density distribution detecting means for detecting, a drive logic control means for sequentially energizing the drive coil in a predetermined direction and order based on a signal of the magnetic flux density distribution detecting means, and the AC power supply for a full wave Rectifying means for rectifying and low voltage DC voltage converting means for converting a high voltage obtained by the rectifying means into a low voltage DC voltage, the magnetic flux density distribution detecting means detects the magnetic flux density distribution waveform, and the magnet rotor It is arranged so as to be substantially similar to the induced voltage waveform induced in the drive coil by rotating, and the drive logic control means has a waveform substantially similar to the waveform detected by the magnetic flux density distribution detection means. A plurality of switching elements for supplying a low-voltage DC voltage generated by the low-voltage DC voltage conversion means to the drive coil based on an instruction of the current waveform control means. A low voltage DC voltage value changing means for changing a value of the low voltage DC voltage generated by the low voltage DC voltage converting means, a current detecting means for detecting a current supplied to the switching element, and the low voltage DC voltage value changing. arranged a supply current value control means that controls to control means control to output torque substantially constant average current supplied to the switching element substantially constant, the current controlled by the value of supply current control means AC power supply direct connection type brushless DC mode characterized by comprising current setting means for setting a value and exposing the current setting means .

A brushless DC motor that is directly connected to an AC power source, a stator having a stator core wound with a drive coil via an insulator, a magnet rotor having a permanent magnet, and a magnetic flux density distribution of the magnet rotor Based on the magnetic flux density distribution detection means to detect, the drive logic control means for sequentially energizing the drive coil in a predetermined direction and order based on the signal of the magnetic flux density distribution detection means, and the AC power supply to the full wave Rectifying means for rectifying and low voltage DC voltage converting means for converting a high voltage obtained by the rectifying means into a low voltage DC voltage, the magnetic flux density distribution detecting means detects the magnetic flux density distribution waveform, and the magnet rotor It is arranged so as to be substantially similar to the induced voltage waveform induced in the drive coil by rotating, and the drive logic control means has a waveform substantially similar to the waveform detected by the magnetic flux density distribution detection means. A plurality of switching elements for supplying a low-voltage DC voltage generated by the low-voltage DC voltage conversion means to the drive coil based on an instruction of the current waveform control means. And low voltage DC voltage value changing means for changing the value of the low voltage DC voltage generated by the low voltage DC voltage converting means, and the average power supplied to the switching element by controlling the low voltage DC voltage value changing means is substantially constant. A power supply value control means for controlling the power supply, a power setting means for setting a power value controlled by the power supply control means, and the power setting means being exposed to be provided. Type brushless DC motor.

In the AC power source directly connected brushless DC motor according to claim 2 or 3, provided the magnetic flux density distribution waveform synthesis means for synthesizing the two phases of the waveform of the magnetic flux density distribution detection unit waveform detected, drive The AC power supply direct-coupled brushless DC motor is characterized in that the logic control means is replaced with drive logic control means for supplying a current substantially similar to the waveform synthesized by the magnetic flux density distribution waveform synthesis means to the drive coil.

In the AC power source directly connected brushless DC motor according to claim 2 or 3, the drive logic control means by the PWM control, AC power source, characterized in that replacing the drive logic control means for forming a current waveform Direct connection type brushless DC motor.

AC power supply direct connection type brushless DC motor according to any one of claims 1-5 permanent magnets of the magnet rotor, characterized in that a polar anisotropic magnet.

An electric device equipped with the brushless DC motor directly connected to an AC power source according to any one of claims 1 to 6 .

The electric device according to claim 7 is any one of a ventilator, a blower, a dehumidifier, a humidifier, a refrigeration device, and a fan filter unit.