JP4639557B2 - DC power supply, DC power supply load device - Google Patents

DC power supply, DC power supply load device Download PDF

Info

Publication number
JP4639557B2
JP4639557B2 JP2001266623A JP2001266623A JP4639557B2 JP 4639557 B2 JP4639557 B2 JP 4639557B2 JP 2001266623 A JP2001266623 A JP 2001266623A JP 2001266623 A JP2001266623 A JP 2001266623A JP 4639557 B2 JP4639557 B2 JP 4639557B2
Authority
JP
Japan
Prior art keywords
power supply
voltage
switch means
current
smoothing capacitor
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
JP2001266623A
Other languages
Japanese (ja)
Other versions
JP2003079152A (en
Inventor
倫雄 山田
守 川久保
和憲 坂廼辺
洋介 篠本
正明 矢部
信也 西田
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Mitsubishi Electric Corp
Original Assignee
Mitsubishi Electric Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Mitsubishi Electric Corp filed Critical Mitsubishi Electric Corp
Priority to JP2001266623A priority Critical patent/JP4639557B2/en
Publication of JP2003079152A publication Critical patent/JP2003079152A/en
Application granted granted Critical
Publication of JP4639557B2 publication Critical patent/JP4639557B2/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Images

Classifications

    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B70/00—Technologies for an efficient end-user side electric power management and consumption
    • Y02B70/10—Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Landscapes

  • Inverter Devices (AREA)
  • Rectifiers (AREA)
  • Dc-Dc Converters (AREA)

Description

【０００１】
【発明の属する技術分野】
本発明は直流電源装置及びこれを使用する装置、特に冷熱空調機器等に使用され力率を改善するもの、交流電源側の高調波を抑制して高調波規制の限度値以下の発生量にするもの、電源側及び負荷側の変動が大きなものに関する。
【０００２】
【従来の技術】
図６は特開平9-247943号公報に示される従来の直流電源装置の構成を示すブロック図である。この図６において１は交流電源、２は交流電源１の電圧を全波整流する４個のダイオードで構成した全波整流回路、３は全波整流回路２の正出力側に一端側が接続され、エネルギーを貯え、電流を平滑にするための直流リアクトル、４は直流リアクトル３の他端側と全波整流回路２の負出力側との間に設けられた直流の母線電圧を平滑するための平滑コンデンサ、５は直流リアクトル３の他端側と平滑コンデンサ４の正側との間に設けられ、平滑コンデンサ４側から全波整流器２へ電流が逆流する事を阻止する逆流阻止用ダイオードである。
【０００３】
６は直流リアクトル３の他端側と全波整流回路２の負出力側との間に設けられ、直流母線間をスイッチングするスイッチ手段、７は平滑コンデンサ４に並列接続された負荷、８は交流電源１の電圧から作成した電源同期信号に基づき電源半周期に少なくとも２回、後述の選択手段が選択した開閉時間でスイッチ手段６を開閉制御する制御手段、９は負荷７の負荷量に応じて予め設定されたスイッチ手段６の開閉時間のデータを格納しておく記憶手段、１０は負荷７の負荷量を検出するための負荷量検出手段、１１は負荷量検出手段１０で検出した負荷量に応じて記憶手段９に予め格納されているスイッチ開閉時間を適切に選択する選択手段である。
【０００４】
次に、動作を説明する。図６に示すようなスイッチ手段６を用い、電源半周期のうち、入力電流の流れない期間中に数回だけ動作させると、スイッチ手段６の動作中は、交流電源１から全波整流器２、直流リアクトル３を通り、スイッチ手段６を経て、全波整流器２を通って、交流電源１に流れるような電流の経路ができる。スイッチ手段６がオン動作して閉じた後であれば、その後にスイッチ手段６を開いたとしても、入力電流が途絶えることはない。これは、直流リアクトル３の性質によるもので、リアクトルは電流を流し続けようとする性質があるため、リアクトルに貯えられたエネルギーが平滑コンデンサ４に充電されることで、入力電流が流れる。従って、直流リアクトル３に貯えられたエネルギーが消費されるまで入力電流は流れ続ける。
【０００５】
図７はゼロクロス点の直後から入力電流が流れる期間の間に２回だけ、スイッチ手段６を動作させた時の入力電流と入力電圧の関係を示した波形図である。なお、Ｔｓｗ１はスイッチ手段６を閉じるまでの第１の遅延時間、Ｔｏｎ１はスイッチ手段６を閉じている第１の閉路時間、Ｔｓｗ２はスイッチ手段６を閉じるまでの第２の遅延時間、Ｔｏｎ２はスイッチ手段６を閉じている第２の閉路時間である。ゼロクロス点通過後、スイッチ手段６を閉じると、前述の通り電流経路ができ、電流が流れる。スイッチ手段６を開いても、直流リアクトル３にはエネルギーが蓄積させており、直流リアクトル３のエネルギー分だけ、電流を流そうと直流リアクトル３が働き、電流がゼロになる前にスイッチ手段６について２回目のスイッチ動作を行う。そして、スイッチ手段６が２回目にオフしたあと、直流電圧より入力電圧のほうが高くなって電流が流れ、図７のような入力電流波形になる。このようにして、入力電流が流れない期間に、スイッチ手段６を動作させて電流を流すことで、電圧と電流の位相差が小さくなり、力率が改善される。また、スイッチ手段６の動作タイミングを制御してやることで、入力電流がピーク付近だけでなく、ゼロクロス付近にも流れるため、高調波が低減されることとなる。
【０００６】
また図８に特公平7-8974３号公報に示される直流電源装置を示す。図８で交流電源１はリアクトル２０およびブリッジ構成の整流回路２を介して整流され、負荷７に直流電力を供給する。４は平滑用コンデンサである。また１９はリアクトルとコンデンサで構成される電源側フィルター、６はスイッチ手段であるパワトランジスタ、５は逆流阻止用ダイオードである。電圧設定器１４で設定された電圧基準E0は直流負荷電圧Ｅと比較され、その差△Ｅが電圧制御増幅器１５で増幅され、掛算器１６で交流電圧信号v1と掛算されて電源位相と同期した誤差信号△ｖに変換される。誤差信号△ｖは比較器１７で電流検出器４０で検出された負荷交流電流信号i1と比較され、△ｖ＞i1のときは比較器１７の論理出力が“１"となつてパワートランジスタ６のベースドライブ回路１８を介してパワトランジスタ１１をオンとし、△ｖ＜i1のときは比較器１７の論理出力が“０"となつてパワトランジスタ６をオフにする。パワトランジスタ６がオンになると負荷側が短絡されて電流i1は増加する。パワトランジスタ６がオフになると電流i1は負荷側すなわち逆流阻止用ダイオード５、平滑コンデンサ４および負荷７に流れ込んで減少し、△ｖ＞i1となつてパワトランジスタ６を再びオンとし、これによつてパワトランジスタ６のオン，オフが比較器１７で形成される電流制御の遅れ要素で決まる数kHzのスイツチング周波数で繰返される。従つて電流i1は図９に示すように上記スイツチング周波数で脈動してほぼ電源電圧ｖと同期し、これによつて力率が１に保たれると共に第３次，第５次、などの高調波がほとんど無くなる。またリアクトルとコンデンサによる電源側フィルタ１９が追加されているので、リアクトル２０のみを用いた場合の整流器の重なり角による電源電圧の落ち込みがなくなり、同期信号としてあたえる電圧信号v1の波形歪みが除去できる。
【０００７】
以上の従来の技術に示される電源装置とその負荷である圧縮機や送風機の電動機を可変速運転するためのインバータ装置はルームエアコンの場合は室外機に収納され、リアクトルおよび電気回路で構成される電源装置およびインバータ装置は、圧縮機や送風機を駆動する事で冷媒を用いた冷熱空調装置として動作する。
【０００８】
変換器回路においてスイッチングを行うときに発生する転流スパイク電圧を吸収するスイッチング手段のスナバダイオードや、スイッチングにより発生する回路の突然の変化を平滑化するフライホイーリングダイオードに対し炭化シリコンダイオードを使用することは特表平１１−５１００００号公報で知られている。更に電源制御回路で逆流防止用ダイオードのショートによる消費電力の改善については、特開平１１−３３２１１３号公報などで知られている。一方冷凍サイクルを冷媒を循環させて空調や冷凍を行う冷熱空調機器などに使用される室外機内の構造として送風機による風路に熱交換器が配置され、熱交換が行われる。熱交換器および送風機の風路を妨げない様に、その側面に圧縮機が配置され、圧縮機の上面にリアクトルが配置される。騒音が大きく高温になる圧縮機およびリアクトルは板金により遮蔽されさらに防音材のカイノールで周囲を覆われる。さらに全体の上面に電気回路部品が配置され、この中には先に述べた直流電源装置のスイッチ手段、逆流防止ダイオードおよびインバータ装置のスイッチ手段が実装される。さらにスイッチ手段および逆流防止ダイオードの放熱フィンも実装される。また電源線への電磁ノイズ対策のためノイズ対策部品のチョークコイル等も実装されている。
【０００９】
【発明が解決しようとする課題】
前項で示される従来の技術では回路のスイッチ手段ならびに、コンデンサからの逆流を防止するためのダイオードに通常のシリコンを用いた素子を用いているため多くの課題を抱えている。まず逆流防止ダイオードが通常のシリコンを用いた素子であるため電圧降下による電力損失が大きく、スイッチ手段のスイッチの如何にかかわらず、電源装置の効率を低下させる。効率性能が基本性能である冷熱空調機器に適用した場合おいて特に大きな課題である。またこれらの逆流防止ダイオードの損失による温度上昇と、逆流防止ダイオードがシリコンを用いた素子である事から使用温度限界が低い事から、素子に大きな放熱部品をつける必要があり、冷熱空調機器に適用した場合冷熱空調機器が大きくなる。また前記の放熱部品を風路に配置しなければならないため電源装置の配置場所のに制約が出てくる。そのため装置が大きくなったり、さらに直流電源装置への配線線路が長くなり電源装置で発生した電磁ノイズの発生量が大きくなり対策部品等のサイズ、コストも大きな課題である。
【００１０】
またスイッチ手段がスイッチした場合にも多くの課題を抱えている。まず逆流防止ダイオードが順方向に電流を流している時、スイッチ手段がオンした場合逆流防止ダイオードは逆バイアスされるが、その時シリコンダイオードのPN接合領域の逆回復電荷が微少時間において非常に大きな逆回復電流を発生し、スイッチ手段を流れ、スイッチ手段のスイッチ損失を非常に大きくしている。現在一般的にパワー用に用いられている定格逆耐圧600V、定格順電流6AのシリコンPN接合ダイオードで逆回復電荷は150〜1500ncもあり、動作温度は125℃までしか保証されていない。そのため電源装置に大きな損失を発生する。先に述べたの損失は効率性能が非常に重視される冷熱空調機器では特に大きな課題で、直流電源装置のスイッチ手段のスイッチ回数を交流電源周期に数回に減らす事で回避されたり、力率改善効果を重視する場合はやむおえず数ｋHzとする事で変換効率を犠牲にしたりしていた。さらにいずれにしても、スイッチ時に電力を蓄積するためのリアクトルに人間の可聴音域である電源周期の数倍もしくは数kHzの電流リップルを発生し、リアクトルから非常に大きな騒音を発生していた。リアクトルの騒音対策のため防音防音対策部品の搭載、防音構造が必要なための設計制約、コストアップが著しい。そのため静音性が要求される、冷熱空調機器とりわけ住環境で使用されるエアコン、冷蔵庫、除湿機等ではこれらの電源装置の使用に制約が多かった。
【００１１】
またスイッチ回数が少ない場合、力率改善ならびに高調波の発生量を抑制しようとした場合、一回あたりリアクトルに蓄積できるエネルギー量を大きくしなくてはならないため、非常に大きく重いリアクトルが必要で、サイズも重量も大きく、コストも高い電源装置となる。元々の持ち運びを前提とした除湿機等では非常に大きな問題である。場合によっては、主機能を発生するモータより、高調波抑制のためのリアクトルの方が大きく重くなる場合もある。またリアクトルの値を大きくする事は、リアクトルの巻き線抵抗値を大きくする事になり、リアクトルの損失が大きくなり、さらに電源装置の効率を低下させる。また先に述べた逆回復電流は電流の時間変化が極めて大きく、大量の高周波ノイズをスイッチ時に発生する。そのため電磁ノイズの対策のためノイズ対策部品が必要で、通常この対策部品にはチョークコイルが用いられ、重量、サイズ、コストを押し上げる事になる。またチョークコイルの抵抗分による電力損失も大きい。さらに冷熱空調機では電源装置の配置にもますます制約が出る。また直流電源装置として電源電圧の変動の大きな太陽電池等の場合や、負荷側から逆流が大きな車両用等の直流電源装置でも同様な問題を抱えている。
【００１２】
本発明は以上のような課題を解決する為になされたもので、電源や負荷の種類に制限されずに高効率で小型軽量な電源装置を得るものである。本発明は効率が良く低騒音の電源装置を得るものである。本発明は性能が良く安価な装置を得るものである。
【００１３】
【課題を解決するための手段】
本発明の直流電源負荷装置は、交流電源からの交流を整流する整流回路または直流電源より供給される直流母線間の直流電圧を平滑する平滑コンデンサと、前記平滑コンデンサより電源側に配置されたスイッチ手段と、前記スイッチ手段より前記電源側に配置され電流エネルギーを蓄積できるリアクトルと、前記平滑コンデンサと前記スイッチ手段の間に配置されて前記平滑コンデンサから電源側への逆流を防止し前記スイッチ手段オフ時に順方向及び逆方向電圧が印加される逆流防止ダイオードと、前記スイッチ手段を開閉する制御手段と、前記平滑コンデンサに並列接続され、直流モータに同期するように前記直流モータの誘起電圧に基づいてスイッチ素子が電気周期一周期に一回スイッチングされるインバータとを備え、 前記制御手段は、前記インバータに接続されたモータの回転数が目標回転数になるように前記スイッチ手段のオン時間を制御するものであり、 前記逆流防止ダイオードは炭化珪素半導体のようなワイドギャップエネルギー帯を有する半導体であることを特徴とするものである。
【００１４】
本発明の直流電源装置は、平滑コンデンサに並列に接続された負荷が軽い状態のときはスイッチ手段を動作させない。
【００１５】
本発明の直流電源装置は、逆流防止ダイオードをショットキー接合ダイオードとしたものである。
【００１６】
本発明の直流電源装置は、平滑コンデンサに並列に接続された負荷を直流ブラシレスモータとし、ブラシレスモータの速度制御を直流電圧を可変する事で行う。
【００１７】
本発明の直流電源装置は、スイッチ手段のスイッチ周波数を非可聴周波数とする。
【００１８】
本発明の直流電源装置は、スイッチ手段は一定時間内に時間設定変更可能なオンとオフを有するサイクルを繰り返すと共にこのサイクル周波数を非可聴周波数とする。
【００１９】
本発明の直流電源装置は、直流電源に太陽電池、蓄電池のように電圧変動の大きな電源を用いたものである。
【００２０】
本発明の直流電源装置は、使用する逆流防止ダイオード以外の半導体部品をシリコン半導体としたものである。
【００２１】
本発明の直流電源負荷装置は、平滑コンデンサに並列に接続された負荷は、負荷に流れる電流が変動する圧縮機用モータ、人や物の移動手段に用いる機器の駆動モータ、送風機用モーター、または系統連系インバータである。
【００２２】
【発明の実施の形態】
実施の形態１．
図１は実施の形態１の直流電源装置の構成を示すブロック図である。図１において１は交流電源、２は交流電源１の電圧を全波整流する４個のシリコンダイオードで構成した全波整流回路、３は全波整流回路２の正出力側に一端側が接続され、エネルギーを貯え、電流を平滑にするための直流リアクトル、４は直流リアクトル３の他端側と全波整流回路２の負出力側との間に設けられた直流の母線電圧を平滑するための平滑コンデンサ、５は直流リアクトル３の他端側と平滑コンデンサ４の正側との間に設けられ、平滑コンデンサ４側から全波整流器2へ電流が逆流する事を阻止する逆流阻止用ダイオードである。
【００２３】
逆流防止ダイオード５は、半導体と金属を接触させてダイオード作用を行うショットキーバリアダイオードを使用する。これは熱的安定性が大きく熱伝導も良い事から高温動作が可能で、また逆回復電荷が非常に少なく逆回復時間が短くそのためスイッチング損失が少なく、合わせて順方向の電圧降下の少ない炭化シリコンを用いたショットキーバリアダイオードを用いる。例えばパワー用に用いられる定格逆耐圧６００V、定格順電流６Aの炭化シリコンショットキーバリアダイオードでは逆回復電荷は２０nc程度とシリコンダイオードPN接合ダイオードに比べ著しく小さい。
【００２４】
６は直流リアクトル３の他端側と全波整流回路２の負出力側との間に設けられ、直流母線間をスイッチングするスイッチ手段、７は平滑コンデンサ４に並列接続されたインバータおよび直流ブラシレスモータ（以後DCBLM）を搭載した空調用圧縮機負荷、８は交流電源１の電圧から作成した電源同期信号、交流電源１の電流信号、後述の回転数検出手段１３から得られる現在の負荷の回転数、後述の電圧検出手段１２から得られる現在の母線電圧および目標回転数から、スイッチ手段６を開閉制御する制御手段、１２は母線電圧の電圧値を検出し低圧電圧信号で制御手段８に伝える電圧検出手段、１３は負荷７のモータの回転数を検出し低圧の電気信号で制御手段８に伝える回転数検出手段である。
【００２５】
図２は図１で示される直流電源装置の負荷の回路並びに構成を示す図で、直流電源装置とあわせて冷熱サイクルの冷媒の圧縮を行う空調装置を構成する。図２で２１〜２６は図1の直流電源装置で選られた直流電圧をスイッチングし交流電圧発生するためのインバータのスイッチでシリコンを用いたIGBTである。図２で３１〜３６は前記IGBTがoff時に順バイアスされ後述のDCBLM圧縮機２７の回生および還流電流を流すシリコンPN接合ダイオードである。図２で２９は前記IGBTスイッチング時、直流電源装置と負荷間のインダクタンスによる直流母線PN間の急峻な電圧変動を吸収するスナバコンデンサである。図２で２７は定常運転時IGBT２１−２６、ダイオード３１−３６、スナバコンデンサ２９から構成される電圧型インバータの主回路からの交流電圧に同期して回転する三相DCBLMを搭載した冷熱サイクルの冷媒を圧縮するDCBLM圧縮機である。図２で２８は、圧縮機27の定常運転時DVBLM圧縮機の相電圧を検出し、２１〜２６のIGBTをon/offさせDCBLMを回転させるDCBLMの制御手段である。
【００２６】
図３は図２の負荷のIGBT２１〜２６のスイッチ動作およびDCBLM圧縮機２７のモータの相電圧を示すタイミング図である。図３で詳細は後述するがA〜Lは圧縮機２７のDCBLMの電気回転周期一周期中にIGBT２１〜２６が通電を切り替えるタイミング間の各通電区間を示す。
【００２７】
次に動作を説明する。まず、図1でスイッチ手段６がまったく動作しない場合は、２の全波整流回路で整流された電流が３のリアクトルおよび５の逆流防止ダイオードを通過し、４のコンデンサに蓄積されパッシブな全波整流による直流電源装置となる。図１に記載の様に整流回路２の出力端子電圧をＶｉ１、スイッチ手段６の直流正母線端子電圧をＶｉ２、平滑コンデンサ４の直流正母線端子電圧をＶｏとする。スイッチ手段６がまったく動作しない場合は、２の全波整流回路で整流された直流がＶｉ２＞Ｖｏ状態では逆流素子用ダイオードに対し順方向のバイアスが掛かりこのダイオードを通して順方向に電流が流れる。なお電圧Ｖｉ２＝Ｖｉ１＋ＶＬであって、この電圧ＶＬは直流リアクトル３に蓄積された電流エネルギーによる増加分である。しかしながら本発明の直流電源装置およぞその負荷では、電源側電圧Ｖｉ２が負荷側電圧Ｖｏより高いとは限らない。電源電圧であるＶｉ１が低下する状態が存在する。更に直流リアクトルの蓄積エネルギーによる電圧増加分は負荷側に放出して低下する。一方負荷側電圧Ｖｏは平滑コンデンサに蓄積されたエネルギーにより電圧が上昇し、負荷７に電力を放出して低下する。更に負荷側モーターが自動車や電車駆動用のモーターなどの場合、移動手段の動いている慣性が大きい状態では、モーターが発電作用を起す場合も存在する。また太陽電池のように負荷として系統に連携するインバータでは負荷側、すなわち系統側の電圧が高い場合が多く存在する。このような多くの場合Ｖｉ２＜Ｖｏの状態が存在し、このときスイッチ手段６が動作しない状態では、全波整流回路２で整流された直流である電源側の電圧が小さく逆流素子用ダイオードに対し負荷側から逆方向のバイアスが掛かりこのダイオードにより順方向に電流が流れない状態となる。
【００２８】
負荷７の消費電力が小さく、交流電源1からの高調波電流および力率が問題にならないレベルの時はスイッチ手段を動作させず、負荷７の側でインバータをパルス幅幅変調（PWM）を用い電圧を可変しモータの回転数を目標の回転数に制御する。この場合直流電源装置はスイッチングしないので、スイッチ手段による損失は発生せず、また逆流阻止用ダイオード5炭化珪素半導体のようにシリコンよりエネルギーギャップの大きなワイドギャップエネルギー帯を有するダイオードを使用するので順方向電圧が低く、運転率の高い軽負荷で直流電源装置を高効率で運転できる。ワイドギャップエネルギー帯を有する半導体として炭化珪素以外にガリウム砒素の半導体やチッカガリウムといわれるガリウムとイトライドの半導体などが知られている。またこのようなワイドギャップエネルギー帯を有するダイオードを使用するので逆方向電圧が印可され長い時間加わり逆電流が流れても素子の熱的安定性が大きく熱伝導度が大きいので、電圧低下の大きな電源を使用しても、あるいは負荷側から大きな電力が供給される場合でも信頼性の高い直流電源装置とすることが出来る。
【００２９】
このように負荷が小さい場合はスイッチ手段６を動作させないが、負荷の大小はモーターの入力電流や回転数を計測し、あるいは圧縮機の冷媒圧力の差を開閉弁の開度で推測したり、あるいは圧縮機から冷凍サイクルに接続される熱交換器の温度など計測可能なデータや推測可能な現象を捉えあらかじめ設定した負荷以下かどうかを判断してスイッチ手段６の動作をさせなければ良い。あるいは電磁ノイズ量が制限値を超えるときだけ、すなわち高周波が規制値を超えた場合、スイッチ手段を動作させるなどの特定条件だけ動作させても良いし、場合によってはほとんどの運転時にスイッチを動作させても良いことは当然である。
【００３０】
次に負荷７の消費電力が大きな場合、すなわち圧縮機の回転数が高く、圧縮機２７から冷凍サイクルに吐出される高温高圧冷媒と空調機などの熱交換器を循環し低温低圧冷媒のこの入出力の冷媒圧力差が大きな場合の直流電源装置の動作について述べる。この場合スイッチ手段６は５０μsec中に一回on/offを行う。制御手段は常に５０μsecの間隔で繰り返し制御をしており、この５０μsec中のonとoffの時間比率を運転状態を検出して制御手段８で逐次制御するパルス幅変調（PWM）とする。図1で、スイッチ手段６のonの間は、交流電源１から全波整流器２、直流リアクトル３を通り、スイッチ手段６を経て、全波整流器２を通って、交流電源１に流れるような電流の経路ができる。スイッチ手段６がオン動作した後であれば、その後にスイッチ手段６をoffしたとしても、しばらくは入力電流が途絶えることはない。これは、直流リアクトル３の性質によるもので、リアクトルは電流を流し続けようとする性質があるため、リアクトルに貯えられたエネルギーが逆流阻止用ダイオード５を通り平滑コンデンサ４に充電されることで、入力電流が流れる。従って、直流リアクトル３に貯えられたエネルギーが消費されるまで入力電流は流れ続ける。なおこの現象は直流リアクトル３が無くとも、図８の交流リアクトル２０が存在する場合でも同様である。リアクトルに蓄積されたエネルギーがスイッチ手段の回路を通して電源側に循環することになる。
【００３１】
直流リアクトル３のインダクタンス値がoff後に次のonまでに充分電流を流し続けられる値ならば、交流電源１からの電流を連続的に流しつづける事ができる。そのためスイッチ手段のon時間を連続的に変調すれば、交流電源１からの電流を連続的に発生させる事ができる。
【００３２】
直流リアクトル３の値と、スイッチ時間の選び方で通常、直流リアクトル３に電流が流れ続けている間にスイッチ手段がonする事があるが、その場合も逆流阻止ダイオード５は逆回復電荷が少ない炭化シリコンダイオードなので、スイッチ手段６がonしてもダイオードからスイッチ手段に流れる逆回復電流は小さくダイオード５およびスイッチ手段６のスイッチ損失は小さく、スイッチ周期を５０μsecとしても損失の小さい直流電源装置を得られる。また損失が小さいのでスイッチ手段および逆流阻止ダイオードの放熱部品も小さくできる。
【００３３】
この場合特に最大５０μ間の電流維持しか必要がないので、直流リアクトルも小さく済み小型化できる。リアクトルが小さい事で、リアクトルの抵抗性分が小さくなり、リアクトルでの損失も下がり小型化できるだけでなく、さらなる高効率化もできる。このサイクル時間を長く取るとリアクトルのチャージ量が大きくなり人の聞こえる周波数帯域に近づくのみならず単位当たりの電圧増加率や電流増加率が増えて直流電源装置に使用する素子など全体に影響することになる。なおスイッチの周期が５０μで、スイッチによる入力電流のリップルは２０kHzとなる。そのためリアクトル３から発生する電流リップルに起因する騒音は人には聞こえない。
【００３４】
先に述べたスイッチ手段６のon時間の決め方であるが、高調波電流を含まない目標電流値と、交流電源1の電流信号からの実際の電流の差を基に制御手段8で決定される。また前記の、目標電流値は実効値が目標回転数と回転数検出手段13から得られる実際の回転数と現在の母線電圧から得られる電流実効値を持つ正弦波状の電流とする。このようにする事で交流電源1からほぼ力率が1に近く高調波電流の少ない状態で電力を取り出し、高効率で直流電圧で駆動される負荷に電力を供給できる小型で軽量な直流電源装置を得る事ができる。スイッチを動作させない条件を設けずにつねにスイッチの周期が５０μで動作させるとすると入力電圧と同相のほぼ正弦波状の電流を得ることが出来る。このように制御手段８にてスイッチ周期毎に正弦波状の電源電圧に同期した正弦波状の目標電流と電流を計測し伝達される計測値との差からスイッチ手段であるＩＧＢＴのＯＮ時間を決定して制御する。目標値より計測値が少ない場合はＯＮ時間を大きく、計測値の方が大きい場合はＯＮ時間を短くする。
【００３５】
なお正弦波状の目標電流の振幅の決め方は母線電圧の目標値に対し母線電圧の計測値との差から決めれば良い。目標に対し実際の母線電圧が低い場合は電流を多くして電圧を増加させる方向とする。また目標に対して母線電圧の計測値が高い場合は電流を絞って母線電圧を低下させる。なおこの目標母線電圧は直流電源装置の供給する負荷に応じて制御しても良い。例えば圧縮機の回転数を制御するため目標回転数と計測値との差に対し制御を加える。ところで図２で負荷のDCBLM圧縮機２７はIGBT２１〜２６をスイッチして得られる交流電圧に同期して回転する。図３でU相に着目すると、DCBLMの相電圧ゼロクロス近傍の通電区間FG,LAの６０度を区間U相のIGBT２１、２２の両方をoffにする事で誘起電圧を相に発生させてそのゼロクロスタイミングを検出し、図２の制御手段２８で同期をとる。誘起電圧の絶対値が高い１２０度区間BCDE、HIJKにIGBT２１もしくは２２をonモータのU相に電圧を印加して回転を維持する。他の相についても同様の動作をする。この通電方式では電気周期一周期に各IGBTは一回しかスイッチされない。
【００３６】
前記の通電方式ではモータの回転数が一定であれば、モータに印加される電圧の実効値はPN間の母線電圧により一意的に決まる。そのためDCBLMの回転数は、母線電圧を可変する事で印加電圧を可変でき制御できる。母線電圧は先に述べた様に図２の制御手段２８、もしくは図1の回転数検出手段１３から図２の制御手段８に伝達され、先に述べた目標電流実効値が可変され最終的に母線電圧が増減し目標のモータ回転数を得て、空調制御を行う。すなわち直流電源装置に回転数制御の機能を持たせている。スイッチ手段６がＯＮするとリアクトルにチャージされその後スイッチがＯＦＦするとリアクトルに貯えられた電圧増分ＶＬが増大して負荷側へ加わることになる。この増大した電圧が平滑コンデンサに貯えられて再びスイッチがＯＮすると、より高い電圧として逆流阻止用ダイオードに加わるが炭化シリコンのようなワイドギャップエネルギー帯を有する半導体を使用するため信頼性が高く損失も小さく出来る。図１でスイッチ６がＯＮされているときはＶｉ２がほぼゼロとなりＶｏが加わるため逆流阻止用ダイオード５には常時逆バイアスが加わることになる。
【００３７】
このような構成と動作で、負荷側では各IGBTおよびダイオードはスイッチ損失が大きく、動作温度の低いシリコンで構成されているが電気周期一周期に1回しかon/offしないので、損失も小さく、放熱構造も簡単で、小型で軽く、スイッチにより発生する電磁ノイズの発生も押さえられる。さらにスイッチしない事でモータに流れる電流リップルが無くなり、モータからのスイッチ音が無く、モータの高周波鉄損も著しく少なく負荷の効率もアップする。
【００３８】
本実施の形態では直流電源装置の高効率化とあわせ負荷側も効率化できるので、冷熱空調機自体を高効率化できる。また直流電源装置側の放熱構造およびリアクトルの小型化とあわせ負荷側の放熱構造の小型化で、冷熱空調機自体、例えば室外機の小型化ができる。
【００３９】
また直流電源装置側のリアクトルの低騒音化とあわせ負荷側のモータの低騒音化で、冷熱空調機自体が低騒音化できる。さらにリアクトルや、モータの防音に用いている強め等の機械部品、ウレタンなどの吸音材や防音構造をなくしたり、簡易化できるためさらに冷熱空調機を小型、軽量化できる。また低騒音であるため、室内で用いる冷熱空調機器等では著しく効果が高い。
【００４０】
また直流電源装置側の低電磁ノイズ化とあわせ負荷側の低電磁ノイズ化で、冷熱空調機自体が低ノイズ化できる。さらに現在ノイズ対策に用いている、電源側ラインフィルタを小さくできたり、電磁シールドが不要となるので空調機を小型、軽量化できる。さらにラインフィルタの小型化は往復線を巻くコモンチョークモードコイルの損失も小さくなり発熱を減らせて構造の簡素化が更に出来、冷熱空調機器等を高効率化できる。
【００４１】
このような小型化や構造の簡素化で、さらに防音、ノイズ対策部品の低減で冷熱空調機等負荷側装置のコストを下げる事になる。また本実施の形態ではシリコンダイオードに比べコストの高い炭化シリコンダイオードを一つだけ用いる事で前記の効果を得られるので、コスト対効果が非常に高い直流電源装置並びに冷熱空調機等の装置が得られる。
【００４２】
図４は別の例の直流電源装置の構成を示すブロック図である。図４において４０は太陽電池の直並列接続による直流電源、３は４０の直流電源の正出力側に一端側が接続され、エネルギーを貯え、電流を平滑にするための直流リアクトル、４は直流リアクトル３の他端側と直流電源４０の負出力側との間に設けられた直流の母線電圧を平滑するための平滑コンデンサ、５は直流リアクトル３の他端側と平滑コンデンサ４の正側との間に設けられ、平滑コンデンサ４側から直流電源４０へ電流が逆流する事を阻止する逆流阻止用ダイオードである。
【００４３】
逆流防止ダイオードは、熱的安定性が大きく熱伝導も良い事から高温動作が可能で、また逆回復電荷が非常に少なく逆回復時間が短くそのためスイッチング損失が少なく、合わせて順方向の電圧降下の少ない炭化シリコンを用いたショットキーバリアダイオードを用いる。現在パワー用に用いられる定格逆耐圧600V、定格順電流6Aの炭化シリコンショットキーバリアダイオードでは逆回復電荷は20nc程度とシリコンダイオードPN接合ダイオードに比べ著しく小さい。
【００４４】
６は直流リアクトル３の他端側と全波整流回路２の負出力側との間に設けられ、直流母線間をスイッチングするスイッチ手段、７は平滑コンデンサ４に並列接続された直流電圧を交流電圧に変換し系統に連系する三相系統連系インバータ、８は交流電源１の電圧から作成した電源同期信号、交流電源1の電流信号、後述の電圧検出手段１２から得られる現在の母線電圧から、スイッチ手段６を開閉制御する制御手段、１２は母線電圧の電圧値を検出し低圧電圧信号で制御手段8に伝える電圧検出手段である。４１は直流電源の電圧を制御手段８に伝える電圧検出手段である。
【００４５】
次に動作について述べる。スイッチ手段６は５０μsec内で一回のon/offが繰り返されるスイッチ動作を行う。図４で、スイッチ手段６のonの間は、直流電源４０から直流リアクトル３を通り、スイッチ手段６を経て、全波整流器２を通って、交流電源１に流れるような電流の経路ができる。スイッチ手段６がonの後であれば、その後にスイッチ手段６をoffしたとしても、しばらくは入力電流が途絶えることはない。これは、直流リアクトル３の性質によるもので、リアクトルは電流を流し続けようとする性質があるため、リアクトルに貯えられたエネルギーが逆流阻止用ダイオード５を通り平滑コンデンサ４に充電されることで、入力電流が流れる。従って、直流リアクトル３に貯えられたエネルギーが消費されるまで入力電流は流れ続け直流電源のエネルギーが電解コンデンサ４に伝達される。制御手段８は電圧検出手段１２の電圧が一定電圧となるように２５μsecのon時間とoff時間を決定する。負荷量が大きく電圧検出手段１２の検出電圧が目標電圧より低い時はスイッチ手段６のon時間が長くなり、逆に目標電圧より低い時はon時間が短くなる。
【００４６】
負荷量すなわち系統に回生する電力量は電圧検出手段４１で検出される直流電源４０すなわち太陽電池の電圧を基に制御手段８で太陽電池の最大発電量を類推し負荷７の負荷量を決定し系統に発電電力を送る。太陽電池は一定の日射量に対し出力できる最大の電力を得られる電圧電流ポイントがあるが、本実施の形態では最大電力が得られる負荷量を日射の状況に応じ常に追随する再大電力点追従制御を行う。この追随制御は出力側電力を若干大小させ電圧と電流の積が光の強度が変化するその時その時最大となる点を探して出力を設定するやり方である。
【００４７】
直流リアクトル３の値と、スイッチ時間の選び方で通常、直流リアクトル３に電流が流れ続けている間にスイッチ手段がonするが、その場合も逆流阻止ダイオード5は逆回復電荷が少ない炭化シリコンダイオードなので、スイッチ６がonしてもダイオードからスイッチ手段に流れる逆回復電流は小さくダイオード５およびスイッチ手段６のスイッチ損失は小さく、スイッチ周期を２５μsecとしても損失の小さい直流電源装置を得られる。また損失が小さいのでスイッチ手段６および逆流阻止ダイオード５の放熱も小さくできる。
【００４８】
また最大２５μ間の電流維持しか必要がないので、直流電源装置で最大サイズで最大重量の直流リアクトルが非常に小さく軽くできる。軽くなる事で、取り付け制約も無くなり、施工時の作業者の人数も少なくて済む。またリアクトルが小さい事で、リアクトルの抵抗性分が小さくなり、リアクトルでの損失や発熱も下がり小型化できるだけでなく、さらなる高効率化もできる。またスイッチの周期が２５μで、スイッチによる入力電流のリップルは４０kHzとなる。そのためリアクトル３から発生する電流リップルに起因する騒音はまったく聞こえない。そのため騒音の少ない直流電源装置が得られる。室内に設置される住宅用の系統連系インバータでは最も騒音の大きな直流リアクトルの騒音を非可聴周波数とする事ができ特に効果が高い。さらに騒音対策で強度アップのためにさらにアップしていたリアクトルの重量がさがり装置全体の重量を下げるという相乗効果もある。
【００４９】
また逆流防止ダイオード５に逆回復電流が少ない炭化シリコンを用いた事で、スイッチングの周期を２５μsecと短くしても電磁ノイズの発生量は著しく小さくできる。そのため電磁ノイズ対策のため直流電源とリアクトルの間に大きなノイズフィルタを必要とする業務用系統連系インバータで特に効果が高い。本発明で逆流につながる条件は、交流電源の場合交流電源を整流したとき平滑次第でリップルが発生し電源周期に対応した逆バイアスが掛かる。直流電源の場合負荷は一定などであるが直流電源の電圧が急激に低下する、太陽電池では日射の低下、蓄電池では電池残量の低下などで逆流が起こる。また負荷側が回生モードとなるインバータ＋モーターの場合は負荷側の回生の発生により母線電圧が急に増加すると逆流が起こる。逆流防止ダイオードの損失は、逆流防止ダイオードが順方向にバイアスされ電流が流れる場合通常のダイオードの両端には順方向電圧が発生し、この電圧と順方向電流の積がダイオードの損失となる。
【００５０】
図５は先に説明した電源装置とその負荷にルームエアコン室外機の圧縮機と送風機およびその電動機を可変速運転するためのインバータ装置としたときのルームエアコン室外機構造の三面図である。図５で５１は室外機の正面図、５２は室外機の上面図、５３は室外機の側面図である。また５４は冷媒を圧縮する圧縮機、５５は送風機、５６は熱交換器、５７は直流電源装置のリアクトル、電源装置およびインバータ装置を含む回路である。
【００５１】
直流電源装置のリアクトル、電源装置およびインバータ装置を含む回路５７で、圧縮機５４および送風機５５を駆動する事で冷媒を用いた冷熱空調装置として動作する。
【００５２】
送風機５５による風路に熱交換器５６が配置され、熱交換が行われる。リアクトルが小型化軽量化したのでリアクトルを回路基板上に実装できる。さらに回路およびリアクトルをおよび圧縮機を、熱交換器５６および送風機５５の風路を妨げない様に、その下面に配置できる。回路５７には先に述べた直流電源装置のスイッチ手段、逆流防止ダイオードおよびインバータ装置のスイッチ手段が実装される。さらに前記スイッチ手段および逆流防止ダイオードの放熱フィンも実装される。また回路には電源線への電磁ノイズ対策のためノイズ対策部品のチョークコイル等も実装されている。
【００５３】
先に説明したように直流電源回路およびインバータを用い、室外機の各部品の配置を回路とリアクトルを共通化でき熱交換器５６および送風機５５の風路を簡素化できる図５の配置とした事で、室外機の幅を小さく軽くする事ができる。そのためベランダ等の狭いスペースにも設置可能な小型で、軽いルームエアコン室外機が得られる。また重量の大きな圧縮機、リアクトルおよび回路を底面に配置できるので、軽い事に加え、重心が低く、持ち上げる時のバランスも良く、施工者が従来に比べ著しく軽く感じるルームエアコンが得られる。更に熱交換器の配置の自由度が増してファンの側面を熱交換器ですべて覆ったり、上部からも空気を取り入れて熱交換器を通過させるなどより熱効率の良い配置を自由に選択できる。
【００５４】
以上の説明では三相モータを負荷としたが他の相数もモータを負荷としても同様の効果が得られる。またDCBLMを負荷としたが誘導電動機、リラクタンスモータ等の他のモータでも同様の効果が得られる。また直流電源に太陽電池を用いたが、鉛畜電池等の電池を用いても同様の効果が得られる。また負荷に系統連系インバータを用いたが、重量が燃料もしくは電気費用に影響することに加え騒音が乗車者の快適性に影響する電車、乗用車および商用車等の車軸もしくはステアリングの駆動用モータを用いても同様に高い効果が得られる。
【００５５】
本発明により安価で変換効率が高く、小型で、軽量で、低騒音で、電磁ノイズの小さな直流電源装置並びに負荷が得られる。
【００５６】
またこの発明によれば逆流防止ダイオードにon損失、スイッチ損失、リカバリー電流の小さなワイドギャップ半導体ダイオードを用いたので、高効率で、小型で、軽量で、低騒音で、電磁ノイズの小さな直流電源装置が得られる。
【００５７】
またこの発明によれば逆流防止ダイオードにon損失、スイッチ損失、リカバリー電流の小さく原料が安価な炭化シリコン半導体ダイオードを用いたので、安価で、高効率で、小型で、軽量で、低騒音で、電磁ノイズの小さな直流電源装置が得られる。
【００５８】
またこの発明によれば逆流防止ダイオードにon損失、スイッチ損失、リカバリー電流の小さく構造が簡単で安価なショットキーダイオードを用いたので、安価で、高効率で、小型で、軽量で、低騒音で、電磁ノイズの小さな直流電源装置が得られる。
【００５９】
またこの発明によれば負荷にモータを用いた事でモータを安価で、高効率で、小型で、軽量で、低騒音で駆動できる直流電源装置が得られる。負荷に圧縮機モータを用いた事で圧縮機を安価で、高効率で、小型で、軽量で、低騒音で駆動できる直流電源装置が得られる。負荷に送風機モータを用いた事で送風機を安価で、高効率で、小型で、軽量で、低騒音で駆動できる直流電源装置が得られる。負荷に直流ブラシレスモータを用いた事でブラシレスモータを安価で、高効率で、小型で、軽量で、低騒音で駆動できる直流電源装置が得られる。
【００６０】
またこの発明によればスイッチ周波数を非可聴周波数とすることで安価で、高効率で、小型で、軽量で、低騒音な直流電源装置およびその負荷が得られる。また安価で、高効率で、小型で、軽量で、低騒音な直流電源装置が得られる。
【００６１】
またこの発明によれば直流電源に太陽電池を用い前記の直流電源装置と組み合わせたことで、安価で、高効率で、小型で、軽量で、低騒音で、電磁ノイズの小さな直流電源装置および太陽光発電システムが得られる。直流電源に畜電池を用い前記の直流電源装置と組み合わせたことで、安価で、高効率で、小型で、軽量で、低騒音で、電磁ノイズの小さな直流電源装置および蓄電システムが得られる。
【００６２】
またこの発明によれば負荷に系統連系インバータを用い直流電源装置と組み合わせたことで、安価で、高効率で、小型で、軽量で、低騒音で、電磁ノイズの小さな直流電源装置および系統連系システムが得られる。またこの発明によれば負荷に人や物の移動手段に用いる機器の駆動モータを用い直流電源装置と組み合わせたことで、安価で、高効率で、小型で、軽量で、低騒音で、電磁ノイズの小さな直流電源装置および移動機器が得られる。
【００６３】
【発明の効果】
本発明の直流電源装置は、交流電源からの交流を整流する整流回路または直流電源より供給される直流母線間の直流電圧を平滑する平滑コンデンサと、平滑コンデンサより電源側に配置されたスイッチ手段と、スイッチ手段より電源側に配置され電流エネルギーを蓄積できるリアクトルと、平滑コンデンサとスイッチ手段の間に配置されて平滑コンデンサから電源側への逆流を防止しスイッチ手段オフ時に順方向及び逆方向電圧が印加される炭化珪素半導体のようなワイドギャップエネルギー帯を有する逆流防止ダイオードと、を備えたので、小型で性能の良い装置が得られる。
【００６４】
本発明の直流電源装置は、平滑コンデンサに並列に接続された負荷が軽い状態のときはスイッチ手段を動作させないので、損失が少ない装置が得られる。
【００６５】
本発明の直流電源装置は、逆流防止ダイオードをショットキー接合ダイオードとしたので、構造が簡単で安価な装置が得られる。
【００６６】
本発明の直流電源装置は、平滑コンデンサに並列に接続された負荷を直流ブラシレスモータとし、ブラシレスモータの速度制御を直流電圧を可変する事で行うので、効率良くモーターを駆動できる。
【００６７】
本発明の直流電源装置は、スイッチ手段のスイッチ周波数を非可聴周波数とするので、低騒音の装置が得られる。
【００６８】
本発明の直流電源装置は、スイッチ手段は一定時間内に時間設定変更可能なオンとオフを有するサイクルを繰り返すと共にこのサイクル周波数を非可聴周波数とするので、音が静かで効率の良い装置が得られる。
【００６９】
本発明の直流電源装置は、直流電源に太陽電池、蓄電池のように電圧変動の大きな電源を用いたので、運転状態により電源電圧が変化しても信頼性が高く効率の良い装置が得られる。
【００７０】
本発明の直流電源装置は、使用する逆流防止ダイオード以外の半導体部品をシリコン半導体としたので、安価な装置が得られる。
【００７１】
本発明の直流電源負荷装置は、平滑コンデンサに並列に接続された負荷は、負荷に流れる電流が変動する圧縮機用モータ、人や物の移動手段に用いる機器の駆動モータ、送風機用モーター、または系統連系インバータであり、負荷側から電源側への逆流があっても信頼性が高く効率の良い装置が得られる。
【図面の簡単な説明】
【図１】 この発明の直流電源装置の構成を示すブロック図。
【図２】 この発明の直流電源装置の負荷の回路および構成図。
【図３】 この発明の直流電源装置の負荷の回路動作およびDCBLM圧縮機のモータの相電圧を示すタイミング説明図。
【図４】 この発明の直流電源装置の構成を示すブロック図。
【図５】 この発明の電源装置とその負荷にルームエアコン室外機の圧縮機と送風機およびその電動機を可変速運転するためのインバータ装置としたときのルームエアコン室外機構造の三面図。
【図６】 従来の直流電源装置の構成を示すブロック図。
【図７】 従来の直流電源装置の入力電流と入力電圧の関係を示した波形図。
【図８】 従来の直流電源装置の回路および制御ブロック図。
【図９】 従来の直流電源装置の入力電流と入力電圧の関係を示した波形図。
【符号の説明】
１ 交流電源、 ２ 全波整流回路、 ３ 直流リアクトル、 ４ コンデンサ、 ５ 逆流防止ダイオード、 ６ スイッチ手段、 ７ 負荷、 ８ 制御手段、 ９ 記憶手段、 １０ 負荷量検出手段、 １１ 選択手段、 １２ 電圧検出手段、 １３ 回転数検出手段、 １４ 電圧設定器、 １５ 電圧制御増幅器、 １６ 掛算器、 １７ 比較器、 １８ ベースドライブ回路、 １９ 電源側フィルタ、 ２０ 交流リアクトル、 ２１〜２６ IGBT、 ２７ DCBLM圧縮機、 ２８ 制御手段、 ２９ スナバコンデンサ、 ３１〜３６ダイオード、 ４０ 直流電源、 ４１ 電圧検出手段、 ５１ ルームエアコン室外機の正面図、 ５２ ルームエアコン室外機の上面図、 ５３ ルームエアコン室外機の側面図、 ５４ 圧縮機、 ５５ 送風機、 ５６ 熱交換器、 ５７ リアクトルおよび回路。[0001]
BACKGROUND OF THE INVENTION
The present invention is a DC power supply device and a device that uses the DC power supply device, particularly those that improve the power factor used in a cooling air conditioner, etc., and suppresses harmonics on the AC power supply side to reduce the generation amount below the limit value of the harmonic regulation. Related to large fluctuations on the power supply side and load side.
[0002]
[Prior art]
FIG. 6 is a block diagram showing a configuration of a conventional DC power supply device disclosed in Japanese Patent Laid-Open No. 9-247943. In FIG. 6, 1 is an AC power source, 2 is a full-wave rectifier circuit composed of four diodes for full-wave rectification of the voltage of the AC power source 1, and 3 is connected at one end to the positive output side of the full-wave rectifier circuit 2, DC reactor 4 for storing energy and smoothing current 4 is a smoothing unit for smoothing the DC bus voltage provided between the other end of DC reactor 3 and the negative output side of full-wave rectifier circuit 2. A capacitor 5 is a reverse current blocking diode that is provided between the other end side of the DC reactor 3 and the positive side of the smoothing capacitor 4 and prevents current from flowing backward from the smoothing capacitor 4 side to the full-wave rectifier 2.
[0003]
6 is provided between the other end of the DC reactor 3 and the negative output side of the full-wave rectifier circuit 2 and switches between the DC buses, 7 is a load connected in parallel to the smoothing capacitor 4, and 8 is an AC Control means for controlling opening / closing of the switch means 6 at an opening / closing time selected by the selection means described later at least twice in a half cycle of the power supply based on the power supply synchronization signal generated from the voltage of the power supply 1, and 9 is according to the load amount of the load 7 Storage means for storing data of opening / closing time of the switch means 6 set in advance, 10 is a load amount detection means for detecting the load amount of the load 7, and 11 is a load amount detected by the load amount detection means 10. Accordingly, it is a selection means for appropriately selecting a switch opening / closing time stored in advance in the storage means 9.
[0004]
Next, the operation will be described. When the switch means 6 as shown in FIG. 6 is used and the switch means 6 is operated only several times during a period in which the input current does not flow, during the operation of the switch means 6, the full-wave rectifier 2, A current path that passes through the DC reactor 3, the switch means 6, the full-wave rectifier 2, and the AC power supply 1 is formed. If the switch means 6 is turned on and closed, the input current will not be interrupted even if the switch means 6 is opened thereafter. This is due to the nature of the direct current reactor 3, and the reactor has the property of continuing to flow current. Therefore, the energy stored in the reactor is charged into the smoothing capacitor 4, whereby the input current flows. Therefore, the input current continues to flow until the energy stored in the DC reactor 3 is consumed.
[0005]
FIG. 7 is a waveform diagram showing the relationship between the input current and the input voltage when the switch means 6 is operated only twice during the period in which the input current flows immediately after the zero cross point. Tsw1 is a first delay time until the switch means 6 is closed, Ton1 is a first closing time when the switch means 6 is closed, Tsw2 is a second delay time until the switch means 6 is closed, and Ton2 is a switch This is the second closing time when the means 6 is closed. When the switch means 6 is closed after passing the zero cross point, a current path is formed as described above, and a current flows. Even if the switch means 6 is opened, energy is accumulated in the direct current reactor 3, and the direct current reactor 3 works to pass the current by the amount of energy of the direct current reactor 3, and the switch means 6 before the current becomes zero. Perform the second switch operation. Then, after the switch means 6 is turned off for the second time, the input voltage becomes higher than the DC voltage and current flows, resulting in an input current waveform as shown in FIG. In this way, the phase difference between the voltage and the current is reduced and the power factor is improved by operating the switch means 6 to flow the current during the period when the input current does not flow. Further, by controlling the operation timing of the switch means 6, since the input current flows not only near the peak but also near the zero cross, harmonics are reduced.
[0006]
FIG. 8 shows a DC power supply device disclosed in Japanese Patent Publication No. 7-89743. In FIG. 8, the AC power source 1 is rectified via a reactor 20 and a rectifier circuit 2 having a bridge configuration, and supplies DC power to the load 7. Reference numeral 4 denotes a smoothing capacitor. Reference numeral 19 denotes a power supply side filter composed of a reactor and a capacitor, 6 denotes a power transistor as a switching means, and 5 denotes a backflow prevention diode. The voltage reference E0 set by the voltage setting unit 14 is compared with the DC load voltage E, the difference ΔE is amplified by the voltage control amplifier 15, and multiplied by the AC voltage signal v1 by the multiplier 16, and synchronized with the power supply phase. It is converted into an error signal Δv. The error signal Δv is compared with the load alternating current signal i1 detected by the current detector 40 by the comparator 17, and when Δv> i1, the logic output of the comparator 17 becomes “1” and the power transistor 6 The power transistor 11 is turned on via the base drive circuit 18, and when Δv <i1, the logic output of the comparator 17 becomes “0” and the power transistor 6 is turned off. When the power transistor 6 is turned on, the load side is short-circuited and the current i1 increases. When the power transistor 6 is turned off, the current i1 flows into the load side, that is, the backflow prevention diode 5, the smoothing capacitor 4 and the load 7 and decreases. When Δv> i1, the power transistor 6 is turned on again. On / off of the power transistor 6 is repeated at a switching frequency of several kHz determined by a current control delay element formed by the comparator 17. Accordingly, as shown in FIG. 9, the current i1 pulsates at the switching frequency and substantially synchronizes with the power supply voltage v. As a result, the power factor is maintained at 1 and the third, fifth, etc. harmonics are maintained. The waves are almost gone. Further, since the power supply side filter 19 including the reactor and the capacitor is added, the power supply voltage does not drop due to the overlapping angle of the rectifier when only the reactor 20 is used, and the waveform distortion of the voltage signal v1 provided as the synchronization signal can be removed.
[0007]
In the case of a room air conditioner, the inverter device for variable speed operation of the power supply device shown in the above prior art and the compressor or blower motor that is the load is housed in an outdoor unit, and is composed of a reactor and an electric circuit. The power supply device and the inverter device operate as a cooling / heating air conditioner using a refrigerant by driving a compressor or a blower.
[0008]
Use silicon carbide diodes for switching means snubber diodes that absorb commutation spike voltages that occur when switching in converter circuits and flywheeling diodes that smooth out sudden changes in the circuit caused by switching This is known from Japanese Patent Publication No. 11-510000. Further, improvement of power consumption by short-circuiting a backflow prevention diode in a power supply control circuit is known from Japanese Patent Application Laid-Open No. 11-332113. On the other hand, a heat exchanger is arranged in an air passage by a blower as a structure in an outdoor unit used for a cold air conditioner that performs air conditioning and refrigeration by circulating a refrigerant in a refrigeration cycle, and heat exchange is performed. In order not to obstruct the air path of the heat exchanger and the blower, the compressor is disposed on the side surface, and the reactor is disposed on the upper surface of the compressor. The compressor and the reactor, which are noisy and have a high temperature, are shielded by sheet metal and are further covered with a soundproof material, quinol. Further, electric circuit components are arranged on the entire upper surface, and the above-described switch means of the DC power supply device, the backflow prevention diode and the switch means of the inverter device are mounted therein. In addition, heat radiation fins for the switch means and the backflow prevention diode are mounted. In addition, noise countermeasure parts such as a choke coil are also mounted as countermeasures against electromagnetic noise on the power line.
[0009]
[Problems to be solved by the invention]
The conventional technique shown in the previous section has many problems because it uses an ordinary silicon element as a circuit switching means and a diode for preventing backflow from the capacitor. First, since the backflow prevention diode is an element using ordinary silicon, the power loss due to the voltage drop is large, and the efficiency of the power supply device is lowered regardless of the switch of the switch means. This is a particularly big problem when applied to a cooling / air-conditioning apparatus whose efficiency performance is a basic performance. Also, since the temperature rise due to the loss of these backflow prevention diodes and the operating temperature limit is low because the backflow prevention diode is an element using silicon, it is necessary to attach large heat dissipation parts to the element, and it is applied to cold air conditioning equipment If so, the cold air conditioning equipment becomes larger. In addition, since the heat dissipating parts must be arranged in the air passage, there is a restriction on the arrangement place of the power supply device. For this reason, the size of the device becomes large, the wiring line to the DC power supply device becomes longer, the amount of electromagnetic noise generated in the power supply device increases, and the size and cost of countermeasure parts and the like are also significant issues.
[0010]
There are also many problems when the switching means is switched. First, when the reverse current prevention diode is conducting a current in the forward direction, the reverse current prevention diode is reverse biased when the switching means is turned on, but at that time, the reverse recovery charge in the PN junction region of the silicon diode is very large in a very short time. A recovery current is generated and flows through the switch means, which greatly increases the switch loss of the switch means. A silicon PN junction diode with a rated reverse breakdown voltage of 600V and a rated forward current of 6A that is generally used for power at present, has a reverse recovery charge of 150 to 1500 nc, and its operating temperature is guaranteed only up to 125 ° C. Therefore, a large loss occurs in the power supply device. The above-mentioned loss is a particularly big problem in the cooling and air-conditioning equipment in which efficiency performance is very important. It can be avoided by reducing the number of switches of the switch means of the DC power supply device to several times in the AC power supply cycle, or power factor When emphasizing the improvement effect, the conversion efficiency is inevitably sacrificed by setting the frequency to several kHz. In any case, a current ripple of several times or several kHz of the power cycle that is a human audible sound range is generated in the reactor for storing electric power at the time of switching, and a very large noise is generated from the reactor. Installation of soundproofing and soundproofing parts for reactor noise countermeasures, design restrictions and cost increase due to the need for soundproofing structure are significant. For this reason, there are many restrictions on the use of these power supply devices in air conditioning equipment, refrigerators, dehumidifiers and the like used in the living environment, which require quietness.
[0011]
In addition, when the number of switches is small, when trying to improve the power factor and reduce the amount of harmonics generated, the amount of energy that can be stored in the reactor must be increased each time, so a very large and heavy reactor is required. The power supply device is large in size, weight, and cost. This is a very big problem with dehumidifiers that are supposed to be originally carried. In some cases, the reactor for suppressing harmonics may be larger and heavier than the motor that generates the main function. Increasing the value of the reactor also increases the winding resistance value of the reactor, increasing the loss of the reactor and further reducing the efficiency of the power supply device. Further, the reverse recovery current described above has a very large time change in current, and a large amount of high frequency noise is generated at the time of switching. For this reason, noise countermeasure parts are required for countermeasures against electromagnetic noise, and choke coils are usually used for these countermeasure parts, which increases weight, size, and cost. Also, the power loss due to the resistance of the choke coil is large. Furthermore, in the case of a cooling / heating air conditioner, there are more restrictions on the arrangement of power supply units. Further, in the case of a solar battery or the like having a large power supply voltage variation as a DC power supply device, or a DC power supply device for a vehicle or the like having a large backflow from the load side, there are similar problems.
[0012]
The present invention has been made to solve the above-described problems, and provides a highly efficient, small, and lightweight power supply device without being limited by the type of power supply or load. The present invention provides an efficient and low noise power supply. The present invention provides a device with good performance and low cost.
[0013]
[Means for Solving the Problems]
A DC power load device according to the present invention includes a rectifier circuit that rectifies AC from an AC power supply or a smoothing capacitor that smoothes a DC voltage between DC buses supplied from a DC power supply, and a switch disposed on the power supply side of the smoothing capacitor. Means, a reactor arranged on the power supply side from the switch means and capable of storing current energy, and arranged between the smoothing capacitor and the switch means to prevent a backflow from the smoothing capacitor to the power supply side and to turn off the switch means Based on the induced voltage of the DC motor, which is connected in parallel to the smoothing capacitor and synchronized with the DC motor, the reverse current prevention diode to which forward and reverse voltages are sometimes applied, the control means for opening and closing the switch means, and the smoothing capacitor. An inverter that is switched once every electrical cycle, and the control means Is for controlling the ON time of the switch means so that the rotational speed of the motor connected to the inverter becomes the target rotational speed, and the backflow prevention diode has a wide gap energy band like a silicon carbide semiconductor. It is characterized by being a semiconductor.
[0014]
The DC power supply device of the present invention does not operate the switch means when the load connected in parallel with the smoothing capacitor is light.
[0015]
In the direct current power supply device of the present invention, the backflow prevention diode is a Schottky junction diode.
[0016]
In the DC power supply device of the present invention, a load connected in parallel to a smoothing capacitor is a DC brushless motor, and speed control of the brushless motor is performed by varying the DC voltage.
[0017]
In the DC power supply device of the present invention, the switch frequency of the switch means is set to an inaudible frequency.
[0018]
In the DC power supply device of the present invention, the switch means repeats a cycle having ON and OFF that can change the time setting within a certain time, and this cycle frequency is set as an inaudible frequency.
[0019]
The DC power supply device of the present invention uses a power supply with large voltage fluctuations such as a solar battery or a storage battery as the DC power supply.
[0020]
In the DC power supply device of the present invention, a semiconductor component other than the backflow prevention diode used is a silicon semiconductor.
[0021]
In the DC power supply load device of the present invention, the load connected in parallel to the smoothing capacitor is a motor for a compressor in which a current flowing through the load fluctuates, a drive motor for a device used as a means for moving a person or an object, a motor for a blower, or It is a grid interconnection inverter.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
Embodiment 1 FIG.
FIG. 1 is a block diagram showing the configuration of the DC power supply device according to the first embodiment. In FIG. 1, 1 is an AC power source, 2 is a full-wave rectifier circuit composed of four silicon diodes for full-wave rectification of the voltage of the AC power source 1, and 3 is connected at one end to the positive output side of the full-wave rectifier circuit 2. DC reactor 4 for storing energy and smoothing current 4 is a smoothing unit for smoothing the DC bus voltage provided between the other end of DC reactor 3 and the negative output side of full-wave rectifier circuit 2. Capacitors 5 are provided between the other end side of the DC reactor 3 and the positive side of the smoothing capacitor 4, and are reverse current blocking diodes for preventing current from flowing back from the smoothing capacitor 4 side to the full-wave rectifier 2.
[0023]
The backflow prevention diode 5 uses a Schottky barrier diode that performs a diode action by bringing a semiconductor into contact with a metal. This is a silicon carbide that has high thermal stability and good heat conduction, so it can operate at high temperature, has a very low reverse recovery charge, has a short reverse recovery time, and therefore has low switching loss and a low forward voltage drop. A Schottky barrier diode using is used. For example, in a silicon carbide Schottky barrier diode having a rated reverse breakdown voltage of 600 V and a rated forward current of 6 A used for power, the reverse recovery charge is about 20 nc, which is significantly smaller than that of a silicon diode PN junction diode.
[0024]
6 is a switch means provided between the other end side of the DC reactor 3 and the negative output side of the full-wave rectifier circuit 2, and switches between DC buses. 7 is an inverter and a DC brushless motor connected in parallel to the smoothing capacitor 4. (Hereinafter referred to as DCBLM) equipped with a compressor load for air conditioning, 8 is a power supply synchronization signal created from the voltage of the AC power supply 1, a current signal of the AC power supply 1, and the current rotational speed of the load obtained from the rotational speed detecting means 13 described later. Control means for controlling opening and closing of the switch means 6 based on a current bus voltage and a target rotational speed obtained from the voltage detection means 12 described later, and a voltage for detecting the voltage value of the bus voltage and transmitting it to the control means 8 with a low voltage signal The detection means 13 is a rotation speed detection means for detecting the rotation speed of the motor of the load 7 and transmitting it to the control means 8 with a low-voltage electric signal.
[0025]
FIG. 2 is a diagram showing a circuit and a configuration of a load of the DC power supply device shown in FIG. 1, and constitutes an air conditioner that compresses the refrigerant in the cooling / heating cycle together with the DC power supply device. In FIG. 2, reference numerals 21 to 26 denote IGBTs using silicon as switches of inverters for switching the DC voltage selected by the DC power supply device of FIG. 1 to generate an AC voltage. In FIG. 2, reference numerals 31 to 36 denote silicon PN junction diodes that are forward-biased when the IGBT is turned off and flow a regenerative and return current of a DCBLM compressor 27 described later. In FIG. 2, reference numeral 29 denotes a snubber capacitor that absorbs steep voltage fluctuations between the DC bus PN due to inductance between the DC power supply and the load during the IGBT switching. In FIG. 2, reference numeral 27 denotes a refrigerant for a cold cycle equipped with a three-phase DCBLM that rotates in synchronization with an AC voltage from a main circuit of a voltage-type inverter composed of IGBTs 21-26, diodes 31-36, and snubber capacitors 29 during steady operation. It is a DCBLM compressor that compresses. In FIG. 2, reference numeral 28 denotes DCBLM control means for detecting the phase voltage of the DVBLM compressor during steady operation of the compressor 27 and turning on / off the IGBTs 21 to 26 to rotate the DCBLM.
[0026]
FIG. 3 is a timing chart showing the switch operation of the IGBTs 21 to 26 and the phase voltage of the motor of the DCBLM compressor 27 of the load shown in FIG. Although details will be described later with reference to FIG. 3, A to L indicate energization intervals between timings at which the IGBTs 21 to 26 switch energization during one electrical rotation period of the DCBLM of the compressor 27.
[0027]
Next, the operation will be described. First, when the switch means 6 does not operate at all in FIG. 1, the current rectified by the 2 full-wave rectifier circuit passes through the reactor 3 and the backflow prevention diode 5 and is accumulated in the capacitor 4 and is passive full-wave. It becomes a DC power supply device by rectification. As shown in FIG. 1, the output terminal voltage of the rectifier circuit 2 is Vi1, the DC positive bus terminal voltage of the switch means 6 is Vi2, and the DC positive bus terminal voltage of the smoothing capacitor 4 is Vo. When the switch means 6 does not operate at all, when the direct current rectified by the full-wave rectifier circuit 2 is in the state of Vi2> Vo, a forward bias is applied to the diode for the backflow element, and a forward current flows through this diode. The voltage Vi2 = Vi1 + VL, and the voltage VL is an increase due to the current energy accumulated in the DC reactor 3. However, in the DC power supply device of the present invention and its load, the power supply side voltage Vi2 is not always higher than the load side voltage Vo. There is a state where the power supply voltage Vi1 decreases. Furthermore, the voltage increase due to the stored energy of the DC reactor is released to the load side and decreases. On the other hand, the voltage on the load side Vo rises due to the energy stored in the smoothing capacitor, and the power is discharged to the load 7 and lowered. Further, when the load side motor is an automobile or a motor for driving a train, there is a case where the motor generates a power generation action in a state where the inertia of the moving means is large. In addition, there are many cases where the voltage on the load side, that is, the system side is high in an inverter that cooperates with the system as a load such as a solar battery. In such a case, the state of Vi2 <Vo exists, and when the switch means 6 does not operate at this time, the voltage on the power source side which is the direct current rectified by the full-wave rectifier circuit 2 is small and the reverse current element diode A reverse bias is applied from the load side, and this diode prevents a current from flowing in the forward direction.
[0028]
When the power consumption of the load 7 is small and the harmonic current and power factor from the AC power source 1 are at a level that does not cause a problem, the switch means is not operated, and the inverter on the load 7 side uses pulse width modulation (PWM). The voltage is varied to control the motor speed to the target speed. In this case, since the DC power supply device does not switch, loss due to the switching means does not occur, and a diode having a wide gap energy band having a larger energy gap than silicon, such as a backflow prevention diode 5 silicon carbide semiconductor, is used in the forward direction. The DC power supply can be operated with high efficiency at light loads with low voltage and high operating rate. As semiconductors having a wide gap energy band, semiconductors of gallium arsenide and semiconductors of gallium and itride called ticker gallium are known in addition to silicon carbide. In addition, since a diode having such a wide gap energy band is used, a reverse voltage is applied, and even if a reverse current flows for a long time, the element has high thermal stability and high thermal conductivity. Even when a large amount of power is supplied from the load side, a reliable DC power supply device can be obtained.
[0029]
The switch means 6 is not operated when the load is small in this way, but the magnitude of the load is measured by measuring the motor input current and the rotational speed, or estimating the difference in the refrigerant pressure of the compressor from the opening of the on-off valve, Alternatively, the switch means 6 may not be operated by determining whether the load is equal to or less than a preset load by capturing measurable data such as the temperature of the heat exchanger connected to the refrigeration cycle from the compressor and a predictable phenomenon. Or only when the amount of electromagnetic noise exceeds the limit value, that is, when the high frequency exceeds the regulation value, it may be operated only for specific conditions such as operating the switch means. Of course, it is okay.
[0030]
Next, when the power consumption of the load 7 is large, that is, the rotation speed of the compressor is high, the high-temperature and high-pressure refrigerant discharged from the compressor 27 to the refrigeration cycle is circulated through a heat exchanger such as an air conditioner, and this entry of the low-temperature and low-pressure refrigerant is performed. The operation of the DC power supply when the output refrigerant pressure difference is large will be described. In this case, the switch means 6 performs on / off once in 50 μsec. The control means always performs repetitive control at intervals of 50 μsec, and the on / off time ratio in 50 μsec is set to pulse width modulation (PWM) in which the operation means is detected and the control means 8 sequentially controls. In FIG. 1, while the switch means 6 is on, the current flows from the AC power supply 1 through the full-wave rectifier 2 and the DC reactor 3, through the switch means 6, through the full-wave rectifier 2, and into the AC power supply 1. Can be routed. After the switch means 6 is turned on, the input current will not be interrupted for a while even if the switch means 6 is turned off thereafter. This is due to the nature of the DC reactor 3, and since the reactor has the property of continuing to flow current, the energy stored in the reactor passes through the backflow prevention diode 5 and is charged to the smoothing capacitor 4, Input current flows. Therefore, the input current continues to flow until the energy stored in the DC reactor 3 is consumed. This phenomenon is the same even when the AC reactor 20 of FIG. The energy stored in the reactor is circulated to the power supply side through the circuit of the switch means.
[0031]
If the inductance value of the DC reactor 3 is a value that allows a sufficient current to flow until the next ON after the OFF, the current from the AC power source 1 can be continuously supplied. Therefore, if the on-time of the switch means is continuously modulated, the current from the AC power source 1 can be continuously generated.
[0032]
Depending on the value of the DC reactor 3 and how to select the switch time, the switch means is usually turned on while the current continues to flow through the DC reactor 3. In this case, the reverse current blocking diode 5 is also carbonized with low reverse recovery charge. Since the silicon diode is used, the reverse recovery current flowing from the diode to the switch means is small even when the switch means 6 is turned on, and the switch loss of the diode 5 and the switch means 6 is small. . Further, since the loss is small, the heat dissipation parts of the switch means and the backflow prevention diode can be reduced.
[0033]
In this case, since it is only necessary to maintain a current of 50 μm at the maximum, the DC reactor can be reduced and the size can be reduced. The small reactor reduces the resistance of the reactor, reduces the reactor loss and reduces the size, and further increases the efficiency. If this cycle time is lengthened, the amount of charge of the reactor will increase and not only will it approach the frequency band that humans can hear, but the voltage increase rate and current increase rate per unit will increase, affecting the elements used for the DC power supply device as a whole. become. The switch period is 50 μ, and the ripple of the input current by the switch is 20 kHz. For this reason, noise caused by the current ripple generated from the reactor 3 cannot be heard by humans.
[0034]
The on-time of the switch means 6 described above is determined by the control means 8 based on the difference between the target current value not including the harmonic current and the actual current from the current signal of the AC power supply 1. . The target current value is a sinusoidal current whose effective value is the target rotational speed, the actual rotational speed obtained from the rotational speed detection means 13, and the current effective value obtained from the current bus voltage. In this way, a small and lightweight DC power supply that can extract power from the AC power supply 1 in a state where the power factor is nearly 1 and with less harmonic current, and can supply power to a load driven by a DC voltage with high efficiency. Can be obtained. If the switch is always operated at a period of 50 μ without providing a condition for not operating the switch, a substantially sinusoidal current in phase with the input voltage can be obtained. In this way, the control means 8 measures the ON time of the IGBT as the switch means from the difference between the sine wave target current synchronized with the sine wave power supply voltage and the measured value transmitted for each switch cycle. Control. When the measured value is smaller than the target value, the ON time is increased, and when the measured value is larger, the ON time is shortened.
[0035]
The amplitude of the sine wave target current may be determined from the difference between the target value of the bus voltage and the measured value of the bus voltage. When the actual bus voltage is lower than the target, the current is increased to increase the voltage. If the measured value of the bus voltage is higher than the target, the current is reduced to lower the bus voltage. This target bus voltage may be controlled according to the load supplied by the DC power supply. For example, in order to control the rotation speed of the compressor, control is applied to the difference between the target rotation speed and the measured value. In FIG. 2, the load DCBLM compressor 27 rotates in synchronization with the AC voltage obtained by switching the IGBTs 21-26. If attention is paid to the U phase in FIG. 3, an induced voltage is generated in the phase by turning off both the IGBTs 21 and 22 of the section U phase at 60 degrees of the energizing sections FG and LA in the vicinity of the DCBLM phase voltage zero cross. The timing is detected, and the control means 28 in FIG. A voltage is applied to the U phase of the on-motor in the 120-degree section BCDE, HIJK where the absolute value of the induced voltage is high, and the rotation is maintained. The same operation is performed for the other phases. In this energization method, each IGBT is switched only once per electrical cycle.
[0036]
In the above energization method, if the rotation speed of the motor is constant, the effective value of the voltage applied to the motor is uniquely determined by the bus voltage between PN. Therefore, the rotational speed of the DCBLM can be controlled by varying the applied voltage by varying the bus voltage. As described above, the bus voltage is transmitted from the control means 28 in FIG. 2 or the rotational speed detection means 13 in FIG. 1 to the control means 8 in FIG. The bus voltage is increased or decreased to obtain the target motor speed, and air conditioning control is performed. That is, the DC power supply device has a function of controlling the rotational speed. When the switch means 6 is turned on, the reactor is charged, and when the switch is turned off thereafter, the voltage increment VL stored in the reactor is increased and applied to the load side. When this increased voltage is stored in the smoothing capacitor and the switch is turned on again, it is added to the backflow blocking diode as a higher voltage, but since a semiconductor having a wide gap energy band such as silicon carbide is used, reliability is high and loss is also caused. Can be small. When the switch 6 is turned on in FIG. 1, Vi2 is almost zero and Vo is applied, so that a reverse bias is always applied to the backflow prevention diode 5.
[0037]
With such a configuration and operation, each IGBT and diode on the load side has a large switch loss and is composed of silicon with a low operating temperature, but it is on / off only once per electrical cycle, so the loss is also small, The heat dissipation structure is simple, small and light, and the generation of electromagnetic noise generated by the switch can be suppressed. Furthermore, by not switching, there is no current ripple flowing through the motor, no switch noise from the motor, high frequency iron loss of the motor is significantly reduced, and load efficiency is increased.
[0038]
In the present embodiment, the load side can be made more efficient together with the higher efficiency of the DC power supply device, so that the cooling / air-conditioning apparatus itself can be made more efficient. In addition, by reducing the size of the heat dissipation structure on the side of the DC power supply and the reactor, the size of the heat dissipation structure on the load side can also be reduced, so that the cooling / heating air conditioner itself, for example, the outdoor unit can be downsized.
[0039]
In addition, the noise on the DC power supply side can be reduced and the noise on the load side motor can be reduced. Furthermore, since the reactor and the mechanical parts used for soundproofing the motor, such as strong mechanical parts, urethane and other sound absorbing materials and soundproofing structures can be eliminated or simplified, the air conditioner can be further reduced in size and weight. In addition, since the noise is low, the effect is remarkably high in a cold air-conditioning apparatus used indoors.
[0040]
In addition, by reducing the electromagnetic noise on the DC power supply side and the electromagnetic noise on the load side, the air conditioner itself can reduce the noise. In addition, the power line filter, which is currently used for noise countermeasures, can be made smaller, and an electromagnetic shield is not required, so the air conditioner can be made smaller and lighter. Further, the downsizing of the line filter reduces the loss of the common choke mode coil wound around the reciprocating wire, reduces heat generation, further simplifies the structure, and improves the efficiency of the cooling / heating air conditioner.
[0041]
Such downsizing and simplification of the structure further reduce the cost of load side devices such as a cold air conditioner by reducing the number of soundproofing and noise countermeasure components. Further, in the present embodiment, the above effect can be obtained by using only one silicon carbide diode, which is more expensive than a silicon diode, so that a DC power supply device and a cold air conditioner that are very cost effective can be obtained. It is done.
[0042]
FIG. 4 is a block diagram showing the configuration of another example DC power supply apparatus. In FIG. 4, 40 is a direct current power supply by series-parallel connection of solar cells, 3 is connected to the positive output side of 40 direct current power supply, one end side is connected to a direct current reactor for storing energy and smoothing current, 4 is a direct current reactor 3 A smoothing capacitor 5 for smoothing the DC bus voltage provided between the other end side of the DC power supply 40 and the negative output side of the DC power supply 40 is provided between the other end side of the DC reactor 3 and the positive side of the smoothing capacitor 4. And a reverse current blocking diode that prevents current from flowing backward from the smoothing capacitor 4 side to the DC power supply 40.
[0043]
The reverse current prevention diode has high thermal stability and good heat conduction, so it can be operated at high temperature, and the reverse recovery charge is very small and the reverse recovery time is short, so the switching loss is small and the forward voltage drop is also reduced. A Schottky barrier diode using a small amount of silicon carbide is used. A silicon carbide Schottky barrier diode with a rated reverse breakdown voltage of 600 V and a rated forward current of 6 A currently used for power has a reverse recovery charge of about 20 nc, which is significantly smaller than that of a silicon diode PN junction diode.
[0044]
6 is a switch means provided between the other end of the DC reactor 3 and the negative output side of the full-wave rectifier circuit 2 and switches between the DC buses. 7 is a DC voltage connected in parallel to the smoothing capacitor 4 to an AC voltage. A three-phase grid-connected inverter that is converted into a grid and connected to the grid, 8 is a power supply synchronization signal created from the voltage of the AC power supply 1, a current signal of the AC power supply 1, and a current bus voltage obtained from the voltage detection means 12 described later. Control means 12 for controlling opening / closing of the switch means 6, and voltage detection means 12 for detecting the voltage value of the bus voltage and transmitting it to the control means 8 by a low voltage signal. Reference numeral 41 denotes voltage detection means for transmitting the voltage of the DC power source to the control means 8.
[0045]
Next, the operation will be described. The switch means 6 performs a switching operation in which on / off is repeated once within 50 μsec. In FIG. 4, while the switch means 6 is on, there is a current path that flows from the DC power supply 40 through the DC reactor 3, through the switch means 6, through the full-wave rectifier 2, and to the AC power supply 1. If the switch means 6 is on, even if the switch means 6 is subsequently turned off, the input current will not be interrupted for a while. This is due to the nature of the DC reactor 3, and since the reactor has the property of continuing to flow current, the energy stored in the reactor passes through the backflow prevention diode 5 and is charged to the smoothing capacitor 4, Input current flows. Accordingly, the input current continues to flow until the energy stored in the DC reactor 3 is consumed, and the energy of the DC power source is transmitted to the electrolytic capacitor 4. The control means 8 determines an on time and an off time of 25 μsec so that the voltage of the voltage detection means 12 becomes a constant voltage. When the load amount is large and the detection voltage of the voltage detection means 12 is lower than the target voltage, the on time of the switch means 6 becomes longer, and conversely, when the load voltage is lower than the target voltage, the on time becomes shorter.
[0046]
The load amount, that is, the amount of power regenerated in the system is determined by the control means 8 based on the voltage of the DC power source 40, that is, the solar cell detected by the voltage detecting means 41, and the load amount of the load 7 is determined by analogy with the maximum power generation amount of the solar cell. Send generated power to the grid. The solar cell has a voltage / current point that can obtain the maximum power that can be output with respect to a certain amount of solar radiation, but in this embodiment, the high power point tracking that always follows the load amount that can obtain the maximum power according to the solar radiation situation. Take control. This follow-up control is a method of setting the output by searching for the point at which the product of the voltage and current becomes the maximum at that time when the light intensity changes, with the output side power slightly increased and decreased.
[0047]
Normally, the switch means is turned on while the current continues to flow through the DC reactor 3 depending on the value of the DC reactor 3 and how to select the switch time. In this case as well, the reverse current blocking diode 5 is a silicon carbide diode with little reverse recovery charge. Even when the switch 6 is turned on, the reverse recovery current flowing from the diode to the switch means is small, the switch loss of the diode 5 and the switch means 6 is small, and a DC power supply device with a small loss can be obtained even if the switch cycle is 25 μsec. Further, since the loss is small, the heat radiation of the switch means 6 and the backflow blocking diode 5 can be reduced.
[0048]
In addition, since it is only necessary to maintain a current of a maximum of 25 μm, the maximum size and maximum DC reactor can be made very small and light in the DC power supply device. Lightening eliminates mounting restrictions and reduces the number of workers during construction. In addition, since the reactor is small, the resistance of the reactor is reduced, and the loss and heat generation in the reactor are reduced, so that not only miniaturization but also higher efficiency can be achieved. Further, the switch cycle is 25 μ, and the ripple of the input current by the switch is 40 kHz. Therefore, noise caused by current ripple generated from the reactor 3 cannot be heard at all. Therefore, a DC power supply device with less noise can be obtained. In a residential grid-connected inverter installed indoors, the noise of the noisy DC reactor can be made an inaudible frequency and is particularly effective. Furthermore, there is a synergistic effect that the weight of the reactor, which has been further increased to increase the strength as a noise countermeasure, is reduced and the weight of the entire apparatus is reduced.
[0049]
Further, by using silicon carbide having a low reverse recovery current for the backflow prevention diode 5, the amount of electromagnetic noise generated can be significantly reduced even if the switching cycle is shortened to 25 μsec. Therefore, it is particularly effective for a commercial grid-connected inverter that requires a large noise filter between the DC power supply and the reactor as a countermeasure against electromagnetic noise. In the case of an AC power supply, the condition that leads to a reverse flow in the present invention is that a ripple occurs depending on smoothness when the AC power supply is rectified, and a reverse bias corresponding to the power supply cycle is applied. In the case of a DC power supply, the load is constant, but the voltage of the DC power supply drops rapidly, the solar battery reduces solar radiation, the storage battery reduces the remaining battery capacity, and so on. In the case of an inverter + motor in which the load side is in the regeneration mode, a reverse flow occurs when the bus voltage suddenly increases due to the occurrence of regeneration on the load side. As for the loss of the backflow prevention diode, when the backflow prevention diode is forward-biased and a current flows, a forward voltage is generated at both ends of the normal diode, and the product of this voltage and the forward current becomes the loss of the diode.
[0050]
FIG. 5 is a three-side view of the structure of the room air conditioner outdoor unit when the power unit described above is used as an inverter device for variable speed operation of the compressor and blower of the room air conditioner outdoor unit and its motor to the load. 5, 51 is a front view of the outdoor unit, 52 is a top view of the outdoor unit, and 53 is a side view of the outdoor unit. Reference numeral 54 denotes a compressor that compresses the refrigerant, 55 a blower, 56 a heat exchanger, and 57 a circuit including a reactor of the DC power supply device, a power supply device, and an inverter device.
[0051]
The circuit 57 including the reactor of the DC power supply device, the power supply device, and the inverter device operates as a cold air conditioner using refrigerant by driving the compressor 54 and the blower 55.
[0052]
A heat exchanger 56 is arranged in the air path by the blower 55 to perform heat exchange. Since the reactor has been reduced in size and weight, the reactor can be mounted on the circuit board. Furthermore, the circuit and the reactor and the compressor can be arranged on the lower surface thereof so as not to obstruct the air path of the heat exchanger 56 and the blower 55. The circuit 57 is mounted with the switching means of the DC power supply device, the backflow prevention diode, and the switching means of the inverter device described above. Further, the switch means and the heat radiation fin of the backflow prevention diode are mounted. The circuit is also equipped with a choke coil, which is a noise countermeasure component, to prevent electromagnetic noise on the power line.
[0053]
As described above, a DC power supply circuit and an inverter are used, and the arrangement of each component of the outdoor unit is made the arrangement of FIG. 5 that can make the circuit and the reactor common, and the air path of the heat exchanger 56 and the blower 55 can be simplified. Thus, the width of the outdoor unit can be reduced. Therefore, a small and light room air conditioner outdoor unit that can be installed in a narrow space such as a veranda can be obtained. In addition, since a heavy compressor, reactor, and circuit can be arranged on the bottom surface, in addition to being light, the center of gravity is low, the balance when lifting is good, and a room air conditioner that feels lighter than before can be obtained. Furthermore, the degree of freedom of arrangement of the heat exchanger is increased, so that the side of the fan is entirely covered with the heat exchanger, or more heat-efficient arrangement such as taking in air from the upper part and passing through the heat exchanger can be freely selected.
[0054]
In the above description, a three-phase motor is used as a load. However, the same effect can be obtained even when the number of other phases is also a motor. Although DCBLM is used as a load, the same effect can be obtained with other motors such as an induction motor and a reluctance motor. Moreover, although the solar cell was used for DC power supply, the same effect is acquired even if it uses batteries, such as a lead livestock battery. In addition, a grid-connected inverter is used for the load, but the axle or steering drive motor for trains, passenger cars, commercial vehicles, etc. whose weight affects fuel and electricity costs and noise affects passenger comfort Even if used, the same high effect can be obtained.
[0055]
According to the present invention, it is possible to obtain a DC power supply apparatus and a load that are inexpensive, have high conversion efficiency, are small, light, have low noise, and have low electromagnetic noise.
[0056]
In addition, according to the present invention, since a wide gap semiconductor diode with small on loss, switch loss, and recovery current is used for the backflow prevention diode, a DC power supply device with high efficiency, small size, light weight, low noise, and low electromagnetic noise Is obtained.
[0057]
In addition, according to the present invention, since a silicon carbide semiconductor diode with low on loss, switch loss, recovery current and low raw material is used for the backflow prevention diode, it is inexpensive, highly efficient, small, lightweight, low noise, A DC power supply device with low electromagnetic noise can be obtained.
[0058]
In addition, according to the present invention, a Schottky diode having a small on-loss, switch loss, and recovery current and a simple and inexpensive structure is used for the backflow prevention diode, so that it is inexpensive, highly efficient, small, lightweight, and low noise. A DC power supply device with small electromagnetic noise can be obtained.
[0059]
Further, according to the present invention, the use of a motor as a load provides a DC power supply device that can be driven with low cost, high efficiency, small size, light weight, and low noise. By using a compressor motor for the load, it is possible to obtain a DC power supply device that can drive the compressor at low cost, high efficiency, small size, light weight and low noise. By using a blower motor for the load, a direct current power supply device that can be driven with low cost, high efficiency, small size, light weight and low noise can be obtained. By using a DC brushless motor as a load, a DC power supply device that can drive the brushless motor at low cost, high efficiency, small size, light weight and low noise can be obtained.
[0060]
In addition, according to the present invention, by setting the switch frequency to an inaudible frequency, a low-cost, high-efficiency, small-sized, light-weight and low-noise DC power supply device and its load can be obtained. Further, an inexpensive, highly efficient, compact, lightweight, and low noise DC power supply device can be obtained.
[0061]
In addition, according to the present invention, a solar battery is used as a direct current power source and combined with the direct current power supply device, so that it is inexpensive, highly efficient, small, lightweight, low noise, and low in electromagnetic noise and solar power. A photovoltaic system is obtained. By using a livestock battery as a DC power source and combining it with the above-described DC power source device, a DC power source device and a power storage system that are inexpensive, highly efficient, small, light, low noise, and low in electromagnetic noise can be obtained.
[0062]
In addition, according to the present invention, a DC power supply using a grid-connected inverter as a load is combined with a DC power supply, so that it is inexpensive, highly efficient, small, lightweight, low noise, and has low electromagnetic noise. A system is obtained. In addition, according to the present invention, a drive motor of equipment used for moving means of people and things is used as a load and combined with a DC power supply device, so that it is inexpensive, highly efficient, compact, lightweight, low noise, electromagnetic noise A small DC power supply device and mobile equipment can be obtained.
[0063]
【The invention's effect】
  The present inventionStraightA rectifying circuit for rectifying alternating current from an alternating current power supply or a smoothing capacitor for smoothing a direct current voltage between direct current buses supplied from a direct current power supply, a switch means disposed on the power supply side from the smoothing capacitor, and a switch means A reactor arranged on the power supply side that can store current energy, and arranged between the smoothing capacitor and the switch means to prevent backflow from the smoothing capacitor to the power supply side, and forward and reverse voltages are applied when the switch means is off. Since a backflow prevention diode having a wide gap energy band such as a silicon carbide semiconductor is provided, a small and high performance device can be obtained.
[0064]
  The present inventionStraightSince the flow power supply device does not operate the switch means when the load connected in parallel to the smoothing capacitor is light, a device with less loss can be obtained.
[0065]
  The present inventionStraightSince the backflow prevention diode is a Schottky junction diode in the flow power supply device, a simple structure and an inexpensive device can be obtained.
[0066]
  The present inventionStraightSince the direct current power supply device uses a DC brushless motor as a load connected in parallel to the smoothing capacitor and performs speed control of the brushless motor by varying the DC voltage, the motor can be driven efficiently.
[0067]
  The present inventionStraightSince the flow power supply device sets the switch frequency of the switch means to an inaudible frequency, a low noise device can be obtained.
[0068]
  The present inventionStraightIn the flow power supply device, the switch means repeats a cycle having ON and OFF that can be changed in time within a certain time and this cycle frequency is set to an inaudible frequency, so that a device with quiet sound and high efficiency can be obtained.
[0069]
  The present inventionStraightSince the direct current power source uses a power source with a large voltage fluctuation, such as a solar battery or a storage battery, as a direct current power source, a highly reliable and efficient device can be obtained even if the power source voltage changes depending on the operating state.
[0070]
  The present inventionStraightSince the semiconductor device other than the backflow prevention diode to be used is a silicon semiconductor in the flow power supply device, an inexpensive device can be obtained.
[0071]
  The present inventionStraightA load connected to a smoothing capacitor is a compressor motor in which the current flowing through the load fluctuates, a drive motor for equipment used for moving people and objects, a fan motor, or a grid connection Even if there is a reverse flow from the load side to the power source side, it is an inverter, and a highly reliable and efficient device can be obtained.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of a DC power supply device according to the present invention.
FIG. 2 is a circuit and configuration diagram of a load of the DC power supply device of the present invention.
FIG. 3 is an explanatory timing diagram showing the circuit operation of the load of the DC power supply device of the present invention and the phase voltage of the motor of the DCBLM compressor.
FIG. 4 is a block diagram showing a configuration of a DC power supply device according to the present invention.
FIG. 5 is a three-sided view of a room air conditioner outdoor unit structure when the power unit of the present invention and an inverter device for variable speed operation of a compressor and a blower of a room air conditioner outdoor unit and a motor for the load are applied to the load.
FIG. 6 is a block diagram showing a configuration of a conventional DC power supply device.
FIG. 7 is a waveform diagram showing the relationship between input current and input voltage of a conventional DC power supply device.
FIG. 8 is a circuit and control block diagram of a conventional DC power supply device.
FIG. 9 is a waveform diagram showing a relationship between an input current and an input voltage of a conventional DC power supply device.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 AC power supply, 2 Full wave rectifier circuit, 3 DC reactor, 4 Capacitor, 5 Backflow prevention diode, 6 Switch means, 7 Load, 8 Control means, 9 Memory | storage means, 10 Load amount detection means, 11 Selection means, 12 Voltage detection Means, 13 rotation speed detection means, 14 voltage setting device, 15 voltage control amplifier, 16 multiplier, 17 comparator, 18 base drive circuit, 19 power supply side filter, 20 AC reactor, 21 to 26 IGBT, 27 DCBLM compressor, 28 Control means, 29 Snubber capacitor, 31-36 diode, 40 DC power supply, 41 Voltage detection means, 51 Front view of room air conditioner outdoor unit, 52 Top view of room air conditioner outdoor unit, 53 Side view of room air conditioner outdoor unit, 54 Compressor, 55 Blower, 56 Heat exchange Vessel, 57 reactors and circuit.

Claims (3)

交流電源からの交流を整流する整流回路または直流電源より供給される直流母線間の直流電圧を平滑する平滑コンデンサと、前記平滑コンデンサより電源側に配置されたスイッチ手段と、前記スイッチ手段より前記電源側に配置され電流エネルギーを蓄積できるリアクトルと、前記平滑コンデンサと前記スイッチ手段の間に配置されて前記平滑コンデンサから電源側への逆流を防止し前記スイッチ手段オフ時に順方向及び逆方向電圧が印加される逆流防止ダイオードと、前記スイッチ手段を開閉する制御手段と、前記平滑コンデンサに並列接続され、直流モータに同期するように前記直流モータの誘起電圧に基づいてスイッチ素子が電気周期一周期に一回スイッチングされるインバータとを備え、
前記制御手段は、前記インバータに接続されたモータの回転数が目標回転数になるように前記スイッチ手段のオン時間を制御するものであり、
前記逆流防止ダイオードは炭化珪素半導体のようなワイドギャップエネルギー帯を有する半導体であることを特徴とする直流電源負荷装置。A rectifier circuit that rectifies alternating current from an alternating current power supply or a smoothing capacitor that smoothes a direct current voltage between direct current buses supplied from a direct current power supply, switch means disposed on the power supply side of the smoothing capacitor, and the power supply from the switch means A reactor arranged on the side for storing current energy, and arranged between the smoothing capacitor and the switch means to prevent a reverse flow from the smoothing capacitor to the power supply side, and forward and reverse voltages are applied when the switch means is off. The switching element is connected in parallel to the smoothing capacitor and synchronized with the DC motor so that the switching element is set to one cycle of the electric cycle based on the induced voltage of the DC motor. An inverter that is switched once ,
The control means controls the ON time of the switch means so that the rotational speed of the motor connected to the inverter becomes a target rotational speed .
The DC power load device, wherein the backflow prevention diode is a semiconductor having a wide gap energy band such as a silicon carbide semiconductor . 交流電源からの交流を整流する整流回路または直流電源より供給される直流母線間の直流電圧を平滑する平滑コンデンサと、前記平滑コンデンサより電源側に配置されたスイッチ手段と、前記スイッチ手段より前記電源側に配置され電流エネルギーを蓄積できるリアクトルと、前記平滑コンデンサと前記スイッチ手段の間に配置されて前記平滑コンデンサから電源側への逆流を防止し前記スイッチ手段オフ時に順方向及び逆方向電圧が印加される逆流防止ダイオードと、前記スイッチ手段を開閉する制御手段と、前記平滑コンデンサに並列接続され、直流モータに同期するように前記直流モータの誘起電圧に基づいてスイッチ素子が電気周期一周期に一回スイッチングされるインバータと、前記平滑コンデンサと前記インバータとの間に配置させた電圧検出手段を備え、
前記制御手段は、前記電圧検出手段で検出した電圧値と、前記インバータに接続されたモータの回転数と目標回転数とに基づいて前記スイッチ手段のオン時間を制御するものであり、
前記逆流防止ダイオードは炭化珪素半導体のようなワイドギャップエネルギー帯を有する半導体であることを特徴とする直流電源負荷装置。A rectifier circuit that rectifies alternating current from an alternating current power supply or a smoothing capacitor that smoothes a direct current voltage between direct current buses supplied from a direct current power supply, switch means disposed on the power supply side of the smoothing capacitor, and the power supply from the switch means A reactor arranged on the side for storing current energy, and arranged between the smoothing capacitor and the switch means to prevent a reverse flow from the smoothing capacitor to the power supply side, and forward and reverse voltages are applied when the switch means is off. The switching element is connected in parallel to the smoothing capacitor and synchronized with the DC motor so that the switching element is set to one cycle of the electric cycle based on the induced voltage of the DC motor. disposed between the inverters times switching between the smoothing capacitor and the inverter Comprising a voltage detecting means which has,
The control means controls the ON time of the switch means based on the voltage value detected by the voltage detection means, the rotational speed of the motor connected to the inverter and the target rotational speed ,
The DC power load device, wherein the backflow prevention diode is a semiconductor having a wide gap energy band such as a silicon carbide semiconductor . 前記スイッチ手段のスイッチ周波数が２０ｋＨｚ以上であることを特徴とする請求項１または２に記載の直流電源負荷装置。  The DC power load device according to claim 1 or 2, wherein a switch frequency of the switch means is 20 kHz or more.
JP2001266623A 2001-09-04 2001-09-04 DC power supply, DC power supply load device Expired - Fee Related JP4639557B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2001266623A JP4639557B2 (en) 2001-09-04 2001-09-04 DC power supply, DC power supply load device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2001266623A JP4639557B2 (en) 2001-09-04 2001-09-04 DC power supply, DC power supply load device

Related Child Applications (1)

Application Number Title Priority Date Filing Date
JP2010156774A Division JP2010220478A (en) 2010-07-09 2010-07-09 Dc power supply and dc power loading device

Publications (2)

Publication Number Publication Date
JP2003079152A JP2003079152A (en) 2003-03-14
JP4639557B2 true JP4639557B2 (en) 2011-02-23

Family

ID=19092882

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2001266623A Expired - Fee Related JP4639557B2 (en) 2001-09-04 2001-09-04 DC power supply, DC power supply load device

Country Status (1)

Country Link
JP (1) JP4639557B2 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010220478A (en) * 2010-07-09 2010-09-30 Mitsubishi Electric Corp Dc power supply and dc power loading device

Families Citing this family (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006129674A (en) * 2004-11-01 2006-05-18 Ecotron:Kk Dc power supply apparatus
JP4765615B2 (en) * 2005-12-26 2011-09-07 三菱電機株式会社 Power converter
JP4983177B2 (en) * 2006-09-15 2012-07-25 サンケン電気株式会社 Power supply overheat detection circuit
JP5029337B2 (en) * 2007-12-12 2012-09-19 株式会社ニコン Power circuit
JP4937281B2 (en) * 2009-01-16 2012-05-23 三菱電機株式会社 Motor drive control device, compressor, blower, air conditioner, refrigerator or freezer
JP2011160503A (en) * 2010-01-29 2011-08-18 Shindengen Electric Mfg Co Ltd Power supply device
JP5477169B2 (en) * 2010-05-27 2014-04-23 株式会社日本自動車部品総合研究所 Power converter
JP2012256729A (en) * 2011-06-09 2012-12-27 Mitsubishi Electric Corp Connection box for photovoltaic power generation
JP2013048180A (en) * 2011-08-29 2013-03-07 Mitsubishi Electric Corp Connection box for photovoltaic generation
JP5640968B2 (en) * 2011-12-26 2014-12-17 新日鐵住金株式会社 Power generation cell system circuit and power generation system using the same
JP5777580B2 (en) * 2012-08-06 2015-09-09 三菱電機株式会社 Terminal box
WO2014106894A1 (en) * 2013-01-07 2014-07-10 三菱電機株式会社 Electric power conversion device and air conditioning device using same
US9614456B2 (en) 2012-11-20 2017-04-04 Mitsubishi Electric Corporation Power conversion apparatus that prevents inrush current and air-conditioning apparatus using the same
CN104682734B (en) * 2013-11-28 2019-02-05 德昌电机(深圳)有限公司 Power-switching circuit
JP6278127B2 (en) * 2014-10-01 2018-02-14 三菱電機株式会社 Dehumidifier
JP2020150711A (en) * 2019-03-14 2020-09-17 東芝ライフスタイル株式会社 Washing machine

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1999033160A1 (en) * 1997-12-19 1999-07-01 Siemens Aktiengesellschaft Electrical circuit arrangement for transforming magnetic field energy into electric field energy
WO2000014809A1 (en) * 1998-09-09 2000-03-16 Hitachi, Ltd. Static induction transistor and its manufacturing method, and power converter
JP2000341937A (en) * 1999-05-28 2000-12-08 Sony Corp Power circuit
JP2001069776A (en) * 1999-08-26 2001-03-16 Rikku:Kk Pam controller
JP2001224175A (en) * 2000-02-09 2001-08-17 Sanyo Electric Co Ltd Power supply unit
JP2001238354A (en) * 2000-02-28 2001-08-31 Matsushita Electric Ind Co Ltd System linked inverter

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1999033160A1 (en) * 1997-12-19 1999-07-01 Siemens Aktiengesellschaft Electrical circuit arrangement for transforming magnetic field energy into electric field energy
JP2001527377A (en) * 1997-12-19 2001-12-25 シーメンス アクチエンゲゼルシヤフト Electric circuit device for converting magnetic field energy to electric field energy
WO2000014809A1 (en) * 1998-09-09 2000-03-16 Hitachi, Ltd. Static induction transistor and its manufacturing method, and power converter
JP2000341937A (en) * 1999-05-28 2000-12-08 Sony Corp Power circuit
JP2001069776A (en) * 1999-08-26 2001-03-16 Rikku:Kk Pam controller
JP2001224175A (en) * 2000-02-09 2001-08-17 Sanyo Electric Co Ltd Power supply unit
JP2001238354A (en) * 2000-02-28 2001-08-31 Matsushita Electric Ind Co Ltd System linked inverter

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010220478A (en) * 2010-07-09 2010-09-30 Mitsubishi Electric Corp Dc power supply and dc power loading device

Also Published As

Publication number Publication date
JP2003079152A (en) 2003-03-14

Similar Documents

Publication Publication Date Title
JP4639557B2 (en) DC power supply, DC power supply load device
CN109874379B (en) Power conversion device and air conditioner
JP6138270B2 (en) DC power supply and refrigeration cycle equipment
US9225258B2 (en) Backflow preventing means, power converting device, and refrigerating and air-conditioning apparatus
AU2010361822B2 (en) Power conversion device and refrigeration air-conditioning device
CN109937531B (en) Power conversion device and refrigerating and air-conditioning machine
KR20170029366A (en) Dc power supply and air conditioner
JP6431413B2 (en) Power conversion device, air conditioner equipped with the same, and power conversion method
JP6671126B2 (en) DC power supply and air conditioner
JP5058314B2 (en) Harmonic suppression device
JP2011160656A (en) Dc power supply
JP4989698B2 (en) POWER CONVERTER, MOTOR DRIVE CONTROL DEVICE EQUIPPED WITH THE SAME, COMPRESSOR AND BLOWER HAVING THE SAME, AND AIR CONDITIONER HAVING THE COMPRESSOR OR BLOWER, REFRIGERATOR AND FREEzer
WO2019159317A1 (en) Power conversion device and air conditioning apparatus using same
JP5664601B2 (en) Room air conditioner
JP5170270B2 (en) Power supply
JP2010220478A (en) Dc power supply and dc power loading device
JP5721669B2 (en) Power converter and refrigeration air conditioning system
JP2019080408A (en) Dc power supply and air conditioner
WO2023084726A1 (en) Power conversion device and apparatus applicable to refrigeration cycle
JP6173435B2 (en) Backflow prevention device, power conversion device and refrigeration air conditioner
JPH061419B2 (en) Power converter

Legal Events

Date Code Title Description
RD01 Notification of change of attorney

Free format text: JAPANESE INTERMEDIATE CODE: A7421

Effective date: 20040705

A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20070927

A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20100426

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20100511

A521 Written amendment

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20100709

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20100817

A521 Written amendment

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20101014

TRDD Decision of grant or rejection written
A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

Effective date: 20101102

A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20101115

R151 Written notification of patent or utility model registration

Ref document number: 4639557

Country of ref document: JP

Free format text: JAPANESE INTERMEDIATE CODE: R151

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20131210

Year of fee payment: 3

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

R250 Receipt of annual fees

Free format text: JAPANESE INTERMEDIATE CODE: R250

LAPS Cancellation because of no payment of annual fees