JP4767435B2

JP4767435B2 - Generator

Info

Publication number: JP4767435B2
Application number: JP2001140179A
Authority: JP
Inventors: 忠後藤; 学鷲津; 克明田中
Original assignee: Nippon Sharyo Ltd
Current assignee: Nippon Sharyo Ltd
Priority date: 2001-05-10
Filing date: 2001-05-10
Publication date: 2011-09-07
Anticipated expiration: 2021-05-10
Also published as: JP2002335696A

Description

【０００１】
【発明の属する技術分野】
本発明は、星形結線した三相交流発電機に関し、特に三相電力のみの使用と三相電力及び単相３線電力の同時使用とを可能にした発電機に関する。
【０００２】
【従来の技術】
工事現場などで使用される可搬式の発電機などには、稼働させる機器や装置などによる異なる負荷に対応すべく、例えば２００Ｖと４００Ｖとの２段階に発電電圧を切替え可能としたものがある。図１３は、発電機に使用される電機子コイルの結線図を示したものである。この発電機は、三相電力の電圧を切り替えられるようにしたものであり、具体的には、図示するようにＵ相、Ｖ相、Ｗ相とも二つずつの電機子コイル１０１〜１０６によって構成し、不図示の切替端子板で図１３（ａ）と図１３（ｂ）とに切り替えられるようにしたものである。そのため、各相で電機子コイル１０１〜１０６が、図１３（ａ）に示すように直列接続すれば高電圧（例えば４００Ｖ）の三相電力が得られ、端子の接続を切り替えて図１３（ｂ）に示すように並列接続すれば低電圧（例えば２００Ｖ）の三相電力が得られる。
【０００３】
一方、こうした三相電力の切り替えの他、三相電力と単相３線電力とを切り替えるようにしたものがある。図１４は、そうした発電機に使用される電機子コイルの結線図を示したものである。これはＵ相、Ｖ相、Ｗ相の電機子コイル２０１〜２０４のうちＶ相だけ２分割して構成し、不図示の切替端子板で図１４（ａ）と図１４（ｂ）とに切り替えられるようにしたものである。そのため、図１４（ａ）に示すように電機子コイル２０２，２０３を直列接続すれば三相電力（例えば２００Ｖ）が得られ、端子の接続を切り替えて図１４（ｂ）に示すようにＶ相の電機子コイル２０３を中性点に対して逆向きに接続すれば、単相３線電力（例えば１００Ｖ）が得られる。
【０００４】
【発明が解決しようとする課題】
しかしながら、従来の発電機において切り替えて得られる出力は、電圧が例えば前述したように三相２００Ｖ、三相４００Ｖ、それに単相１００Ｖなどの単一の電圧のみであった。これに対して工事現場などでは、発電機が、例えば電動工具や現場事務所における電気機器の電源として単相２００Ｖや単相１００Ｖで使用され、水中ポンプや溶接機等の電源としては三相２００Ｖで使用されることが多い。工事現場ではこうた負荷に対する電源種類が複数あるため、従来は電源仕様の異なる負荷には個別に電源を用意するか、トランス等を使用して電源をつくる必要があった。
【０００５】
具体的には、三相２００Ｖと単相１００Ｖの負荷を同時に使用するには、三相２００Ｖ出力の発電機の他に、図１４（ｂ）に示すように電機子コイル２０１〜２０４を結線した単相１００Ｖの別の発電機を用意するか、図１４（ａ）に示すように電機子コイル２０１〜２０４を結線した発電機の出力をトランス等によって単相１００Ｖに変換する必要があった。そのため、三相電力と単相３線電力を必要とする場合には別の発電機やトランス等が必要であり、従来の工事現場では運用コストが高くなってしまっていた。
更に、図１４（ｂ）に示すように切り替えて単相３線電力を得ようとした場合、電機子コイル２０２が使用されずにいたため、その分だけ発電機本来の発電能力を活かせないで無駄が生じていた。
【０００６】
そこで、本発明は、係る課題を解決すべく、三相電力のみの使用に加えて三相電力及び単相３線電力の同時使用とを切り替えて使用可能にした発電機を提供することを目的とする。
【０００７】
【課題を解決するための手段】
本発明の発電機は、中性点に三相の電機子コイルが星形結線され、三相電力の出力と単相３線電力の出力との結線状態の切り替えが可能な切替手段を有し、前記三相の電機子コイルは、第１相及び第２相が各相に巻数の等しい二つの電機子コイルを備え、第３相が前記第１相及び第２相における電機子コイルと巻数の等しい同巻電機子コイルを一つと巻数半分の半巻電機子コイルを二つ備えたものであり、前記切替手段は、三相電力のみの出力の場合には、各相の電機子コイルを中性点と出力端子との間に直列接続にするか、或いは巻数を等しくして並列接続させ、三相電力及び単相３線電力の出力の場合には、前記第１相及び第２相の電機子コイルを中性点と出力端子との間に並列接続させ、前記第３相における半巻電機子コイルを並列にし且つ同巻電機子コイルとは位相を１８０度ずらせて、該半巻電機子コイルと同巻電機子コイルとをそれぞれ中性点と出力端子との間に接続させるように切り替えるものであることを特徴とする。
【０００９】
よって、本発明によれば、二相分には巻数の等しい電機子コイルを二つずつ備え、残る一相分にはこれらと同じ電機子コイルを一つと、巻数半分にした電機子コイルとを二つ備えるようにしたので、切り替え手段によって先ず、各相の電機子コイルを中性点と出力端子との間に直列接続にするかあるいは巻数を等しくして並列接続させるようにすれば、高電圧と低電圧との三相電力を切り替えて出力することができる。そして次に、二相の電機子コイルを中性点と出力端子との間に並列接続し、残りの一相における巻数半分の電機子コイルを巻数の等しい電機子コイルとは逆向きかつ並列にそれぞれ中性点と出力端子との間に接続させるようにすれば、三相電力と単相３線電力とが同時に出力することができる。
【００１０】
また、本発明の発電機は、前記切替手段が、前記三相電力のみの使用と前記三相電力及び単相３線電力の同時使用との切り替えを、端子への接続変更を行うことで達成する切替端子板であることを特徴とする。
また、本発明の発電機は、前記切替手段が、前記切替端子板に加えて、前記第３相における半巻電機子コイルの接続を、当該第３相における同巻電機子コイルに対して同位相で直列接続させる場合と位相を１８０度ずらせて並列接続させる場合との切り替えを行うナイフスイッチを有するものであることを特徴とする。
よって本発明によれば、従来と同じく切替端子板によって切り替えることができるため、従来の切替操作と何ら変わることなく使いやすい。また、ナイフスイッチを用いれば、三相電力と単相３線電力との同時使用に容易に切り替えることができて使い勝手が良い。
【００１１】
【発明の実施の形態】
次に、本発明に係る発電機の一実施形態について図面を参照しながら以下に説明する。本実施形態の発電機は、三相電力のみの使用と、三相電力及び単相３線電力の同時使用を可能にしたものであり、図１は三相電力（２００Ｖ）のみの使用時における電機子コイルの結線図であり、図２は三相電力（２００Ｖ）及び単相３線電力（２００／１００Ｖ）同時使用時における結線図である。具体的には、図１に示す三相電力のみの使用時は、中性点Ｏ１にＵ相、Ｖ相、Ｗ相の電機子コイル１〜７が星形結線され、Ｕ相、Ｖ相、Ｗ相とも巻数を等しくした一対の電機子コイルが中性点Ｏ１と接点Ｕ，Ｖ，Ｗとの間に並列に接続されている。そして特にＶ相は、一方が巻数を半分にして２分割した電機子コイル５，６が直列に接続されている。
【００１２】
ここで、図３は図１及び図２に示す相電圧のベクトル図である。そのうち図３（ａ）は、この三相電力の電圧ベクトル図であり、図３（ｂ）は、単相３線電力の電圧ベクトル図である。図１のように電機子コイル１〜７を星形結線した発電機では、Ｕ相、Ｖ相、Ｗ相に図３（ａ）に示すような大きさが等しく互いに１２０゜ずつ位相が異なる相電圧Ｅｕ，Ｅｖ，Ｅｗが発生する。そして、各相の出力端子間には、相電圧Ｅｕ，Ｅｖ，Ｅｗによって大きさが等しく１２０゜ずつ位相が異なる対称三相交流電圧の線間電圧が得られる。線間電圧は、相電圧の√３倍であり、１１５Ｖの相電圧に対して２００Ｖの線間電圧が発生し、２００Ｖの三相電力が得られる。
【００１３】
次に、図２に示す三相電力及び単相３線電力の同時使用時には、Ｖ相の電機子コイル５，６の接続が切り替えられる。こうして切り替えられた発電機は、Ｖ相の電機子コイル２とＵ相及びＷ相における各一つの電機子コイル１，３とが星形結線される。そしてまた一方で、切り替えられた巻数半分の電機子コイル５，６は図１の場合とは逆方向に並列接続され、Ｕ相及びＷ相では他の一つの電機子コイル４，７がＶ結線されている。従って、この場合には、星形結線された各相の電機子コイル１，２，３による電圧ベクトルが図３（ａ）に示すようになり、Ｖ相の電機子コイル５，６及びＵ相、Ｗ相の電機子コイル４，７による電圧ベクトルが図３（ｂ）に示すようになる。
【００１４】
図３（ａ）に示す電圧ベクトルは、各相１つずつの電機子コイル１，２，３によって発生した、大きさが等しく互いに１２０゜ずつ位相が異なる相電圧Ｅｕ，Ｅｖ，Ｅｗである。そのため、切り替え後でも各電機子コイル１，２，３の出力端子間には、図１に示す三相電力のみの使用時と同様に対称三相交流電圧の線間電圧が得られる。そして、その線間電圧は、相電圧の√３倍であり、１１５Ｖの相電圧に対して２００Ｖの線間電圧が発生し、２００Ｖの三相電力が得られる。ただしこの場合、Ｖ相の電機子コイルが一つに減るため電力は１／２に減少することになる。
【００１５】
一方、図３（ｂ）に示す電圧ベクトルは、Ｕ相、Ｗ相の電機子コイル４，７による相電圧Ｅｕ，Ｅｗと、Ｏ相の電機子コイル５，６による相電圧Ｅｏである。ここで相電圧Ｅｏは、電機子コイル５，６の巻数が半分で逆方向に接続されているため、電圧１／２で位相が反転している。従って、電機子コイル４，７の出力端子間の出力をとれば２００Ｖの単相３線電力が得られ、電機子コイル５，６と電機子コイル４，７との各出力端子間の出力をとれば１００Ｖの単相３線電力が得られる。
【００１６】
よって、電機子コイル１〜７からなる本実施形態の発電機では、図１及び図２に示すように接続を切り替えれば、図１に示すようにして三相電力のみを得ることができ、また図２に示すように切り替えれば、三相電力とともに２００Ｖ又は１００Ｖの単相３線電力を同時に得ることができる。そのため、別に発電機を用意したりトランスなどを用いる必要がなくなり、１台の発電機で三相電力と単相３線電力に対応する負荷の電源として同時に使用することができるようになるので、運用コストがかからなくなった。更に、三相電力と単相３線電力とを同時使用にしたので、機能しない電機子コイルがなくなって発電機のもつ能力を十分に引き出せるようになった。
【００１７】
続いて、こうした電機子コイル１〜７を備えた発電機について、切替手段を含めた構成を以下に説明する。図４は、図１及び図２に示す状態に電機子コイルの接続を切り替える切替手段を含めた、発電機の第１実施形態を示す回路図である。ここでは、Ｕ相、Ｖ相、Ｗ相の電機子コイル１，２，３，４，７が、図示するように中性点Ｏ１と各接点Ｕ，Ｖ，Ｗとの間に接続され、各接点Ｏ１，Ｕ，Ｖ，Ｗから三相電力を取り出す三相端子板２１へと接続され、接点Ｕ，Ｗでは更に単相３線電力を取り出す単相端子板２２にも接続されている。一方、Ｖ相の電機子コイル５，６は、切替端子板２３を介して中性点Ｏ１や接点Ｏ，Ｖから三相端子板２１及び単相端子板２２へと接続されている。切替端子板２３は、図１及び図２の切り替えを短絡板２５，２６，２７によって行うものであり、実線で示す接続状態で図１に示すように電機子コイル５，６が接続され、一点鎖線で示す状態で図２に示すように接続される。
【００１８】
そこで、先ず図１に示す三相電力のみの使用時には、切替端子板２３の短絡板２５，２６，２７を図４の実線で示すように連結させる。このときＶ相の電機子コイル５，６は、その接点Ｖ２，Ｙ１が短絡板２５を介して接続され、そして電機子コイル５の接点Ｖ１が短絡板２６を介して接点Ｖに、また電機子コイル６の接点Ｙ２が短絡板２７を介して中性点Ｏ１に接続される。従って、電機子コイル５，６は、中性点Ｏ１と接点Ｖとの間に直列かつ電機子コイル２と並列に接続される。一方、Ｕ相の電機子コイル１，４とＷ相の電機子コイル３，７とは、中性点Ｏ１と接点Ｕ，Ｗとの間にそれぞれ並列接続されている。従ってこの場合、電機子コイル１〜７は図１に示す接続状態となり、各Ｕ，Ｖ，Ｗ接点に接続された三相端子板２１の出力端子Ｒ，Ｓ，Ｔからは三相電力を得ることができる。
【００１９】
次に、図２に示すように三相電力と単相３線電力との同時使用を行う場合には、切替端子板２３の短絡板２５，２６，２７が図４の一点鎖線で示すように切り替えられる。このときＶ相の電機子コイル５は、その接点Ｖ１が切替端子板２３の端子Ｖ１−Ｖ１から短絡板２７を介して中性点Ｏ１に接続され、電機子コイル６は、その接点Ｖ２が切替端子板２３の端子Ｖ２−Ｖ２及び短絡板２６を経て、同様に端子Ｖ１−Ｖ１から短絡板２７を介して中性点Ｏ１に接続される。一方、電機子コイル５は、その接点Ｙ１が短絡板２５から端子Ｙ２−Ｙ２を介して接点Ｏに連結され、また電機子コイル６は、その接点Ｙ２が直接接点Ｏに連結されている。このように電機子コイル５，６は、前述した切り替え前とは逆向きに接続される。そして、他の電機子コイル１，２，３，４，７については、その接続状態に変わりはない。
【００２０】
従ってこの場合、電機子コイル１〜７は図２に示す接続状態となり、Ｕ相、Ｖ相、Ｗ相の電機子コイル１，２，３に発生した相電圧によって、Ｕ，Ｖ，Ｗ接点に接続された三相端子板２１の出力端子Ｒ，Ｓ，Ｔから三相電力を得ることができる。そしてまた、Ｕ相、Ｗ相の電機子コイル４，７は、そのＵ，Ｗ接点から単相端子板２２の出力端子Ｕ，Ｗに接続され、Ｏ相（図２参照）の電機子コイル５，６は接点Ｏから出力端子Ｎに接続される。そのため、出力端子Ｕ，Ｗ間の出力をとれば２００Ｖの単相３線電力を得ることができ、出力端子Ｕ，Ｎ／Ｕ，Ｗ間の出力をとれば１００Ｖの単相３線電力を得ることができる。
【００２１】
よって、本実施形態の発電機によれば、切替端子板２３の短絡板２５，２６，２７の切り替えによって、三相電力のみの出力に加え、三相端子板２１及び単相端子板２２から同時に三相電力と単相３線電力を得ることができる。そのため、切り替えの度に負荷の着脱を行う必要もない。また、この場合、切替端子板２１の短絡板２５，２６，２７のみで切り替えができるため、切り替え操作も容易である。ここで、切替端子板２３に代えてナイフスイッチ等の切替スイッチを使用すれば操作は更に容易になる。
【００２２】
次に図５は、図１及び図２に示す状態に電機子コイルの接続を切り替える切替手段を含めた、発電機の第２実施形態を示す回路図である。本実施形態は、図４で示したものと切替端子板が異なるだけなので、同様の構成については同符号を付して説明は省略する。本形態でも図１及び図２の切り替えを切替端子板３０によって行い、短絡板３１，３２，３３が実線で示す接続状態の場合に電機子コイル１〜７が図１に示すように接続でき、一点鎖線で示す接続状態の場合に図２に示すように接続できるようにしたものである。
【００２３】
そこで、先ず図１に示すように三相電力のみの使用時に、短絡板３１，３２，３３を図５の実線で示すように連結する。このときＶ相の電機子コイル５，６は、その接点Ｖ２，Ｙ１が短絡板３１を介して直列に接続され、そして電機子コイル５の接点Ｖ１が短絡板３２を介して接点Ｖに、そして電機子コイル６の接点Ｙ２が短絡板３３を介して中性点Ｏ１に接続される。従って、電機子コイル５，６は、中性点Ｏ１と接点Ｖとの間で直列かつ電機子コイル２と並列に接続される。一方、Ｕ相の電機子コイル１，４とＷ相の電機子コイル３，７とは、中性点Ｏ１と接点Ｕ，Ｗとの間にそれぞれ並列接続されている。従ってこの場合、電機子コイル１〜７は図１に示す接続状態となり、各Ｕ，Ｖ，Ｗ接点に接続された三相端子板２１の出力端子Ｒ，Ｓ，Ｔからは三相電力を得ることができる。
【００２４】
次に、図２に示すように三相電力と単相３線電力の同時使用を行う場合には、切替端子板３０の短絡板３１，３２，３３を図５の一点鎖線で示すように切り替える。このときＶ相の電機子コイル５は、その接点Ｖ１が短絡板３３を介して中性点Ｏ１に接続され、電機子コイル６は、その接点Ｖ２が短絡板３２，３３を介して中性点Ｏ１に接続される。一方、電機子コイル５は、その接点Ｙ１が短絡板３１から端子Ｙ１−Ｙ２を介して接点Ｏに連結され、また電機子コイル６は、その接点Ｙ２が直接接点Ｏに連結されている。このように電機子コイル５，６は、前述した切り替え前とは逆向きに接続される。そして、他の電機子コイル１，２，３，４，７については、その接続状態に変わりはない。
【００２５】
従ってこの場合、電機子コイル１〜７は図２に示す接続状態となり、Ｕ相、Ｖ相、Ｗ相の電機子コイル１，２，３に発生した相電圧によって、Ｕ，Ｖ，Ｗ接点に接続された三相端子板２１の出力端子Ｒ，Ｓ，Ｔから三相電力を得ることができる。そしてまた、Ｕ相、Ｗ相の電機子コイル４，７は、そのＵ，Ｗ接点から単相端子板２２の出力端子Ｕ，Ｗに接続され、Ｏ相（図２参照）の電機子コイル５，６は接点Ｏから出力端子Ｎに接続される。そのため、出力端子Ｕ，Ｗ間の出力をとれば２００Ｖの単相電力を得ることができ、出力端子Ｕ，Ｎ／Ｎ，Ｗ間の出力をとれば１００Ｖの単相電力を得ることができる。
【００２６】
よって、本実施形態の発電機によれば、切替端子板３０の短絡板３１，３２，３３の切り替えによって、三相電力のみの出力に加え、三相端子板２１及び単相端子板２２から同時に三相電力と単相３線電力を得ることができる。そのため、切り替えの度に負荷の着脱を行う必要もない。また、この場合、切替端子板３０の短絡板３１，３２，３３のみで切り替えができるため、切り替え操作も容易である。
【００２７】
ところで、前記実施形態の発電機では、三相電力を２００Ｖ専用とすれば、２００Ｖの三相電力と２００Ｖ又は１００Ｖの単相３線電力の同時使用とが可能となる。しかし、工事現場などでは、図１３の従来例のところでも述べたように、低電圧（２００Ｖ）に加えて高電圧（４００Ｖ）の出力切り替えが可能な発電機の要求がある。そこで本実施形態では、更に高電圧の三相電力のみの使用も可能とした発電機について説明する。図６は、高電圧の三相電力のみの使用時における電機子コイルの結線図であり、図１及び図２に示す電機子コイル１〜７の接続を切り替えたものである。高電圧の三相電力のみの使用時には、図６に示すように各相毎に各電機子コイル１〜７を直列接続する。このとき星形結線されたＵ相、Ｖ相、Ｗ相には、図３（ａ）に示す場合と同様に大きさが等しく互いに１２０゜ずつ位相が異なる相電圧が発生し、各相の出力端子間には、相電圧によって大きさが等しく１２０゜ずつ位相が異なる対称三相交流電圧の線間電圧が得られる。線間電圧は、相電圧の√３倍であり、２３０Ｖの相電圧に対して４００Ｖの線間電圧が発生し、４００Ｖの三相電力が得られる。
【００２８】
続いて、こうした高電圧の三相電力のみの使用を加え、低電圧の三相電力のみの使用と、三相電力及び単相３線電力の同時使用の３パターンについて切り替えを可能にした発電機について説明する。図７〜図９は、図１、図２及び図６に示す状態に電機子コイルの接続を切り替える切替手段を含めた、発電機の第３実施形態を示す回路図である。ここでは、切り替えに切替端子板４１に加えて３Ｐナイフスイッチ４２を使用している。そこで先ず、図１に示す低電圧（２００Ｖ）の三相電力のみの使用時には、図７に示すように切替端子板４１及び３Ｐナイフスイッチによって図示するように接続する。
【００２９】
このとき、Ｕ相の電機子コイル１，４とＷ相の電機子コイル３，７とは、中性点Ｏ１と三相端子板２１の出力端子Ｒ，Ｔとの間に並列接続される。すなわち、電機子コイル１，３は、その接点Ｘ，Ｚが切替端子板４１のジョイントバー４５を介して各端子Ｘ，Ｚから端子Ｏを経て中性点Ｏ１に接続され、電機子コイル４，７は直接中性点Ｏ１に接続されている。また、電機子コイル１，３は、その接点Ｕ，Ｗが直接出力端子Ｒ，Ｔに接続され、電機子コイル４，７は、その接点Ｕ１，Ｗ１が切替端子板４１を介して各端子Ｕ，Ｗに接続される。
【００３０】
一方、Ｖ相では、電機子コイル５，６の接点Ｙ１，Ｖ２が３Ｐナイフスイッチ４２のスイッチ４７を介して直列接続されている。従ってＶ相では、この電機子コイル２と電機子コイル５，６とが、中性点Ｏ１と三相端子板２１の出力端子Ｓとの間に並列接続される。すなわち、電機子コイル２は、その接点Ｙが切替端子板４１のジョイントバー４５を介して端子Ｙから端子Ｏを経て中性点Ｏ１に接続され、電機子コイル６は、その接点Ｙ２がスイッチ４６を介して接続される。また、電機子コイル２は、その接点Ｖが直接出力端子Ｓに接続され、電機子コイル５は、その接点Ｖ１がスイッチ４８を介して切替端子板４１の端子Ｖを介して接続される。従ってこの場合、図１に示すようにＵ相、Ｖ相、Ｗ相に並列接続された各電機子コイル１〜７に発生する相電圧によって、三相端子板２１の出力端子Ｒ，Ｓ，Ｔから２００Ｖ三相電力を得ることができる。
【００３１】
次に、図２に示すように三相電力（２００Ｖ）と単相３線電力（２００／１００Ｖ）の同時使用を行う場合には、図８に示すように切替端子板４１及び３Ｐナイフスイッチによって図示するように接続する。この場合、切替端子板４１の接続に変化はなく、電機子コイル１，２，３，４，７について接続状態に変わりはない。一方、３Ｐナイフスイッチ４２が切り替えられるため、電機子コイル５，６の接続が逆方向で並列になる。具体的には、出力端子Ｓ側に接続されていた電機子コイル５，６の接点Ｖ１，Ｖ２は、スイッチ４８，４７を介して中性点Ｏ１に接続され、また電機子コイル５の接点Ｙ１は直接単相端子板２２の出力端子Ｎに接続されて、電機子コイル６の接点Ｙ２がスイッチ４６を介して接続される。
【００３２】
従って、Ｕ相、Ｖ相、Ｗ相の電機子コイル１，２，３に発生した相電圧によって、Ｕ，Ｖ，Ｗ接点に接続された三相端子板２１の出力端子Ｒ，Ｓ，Ｔから２００Ｖの三相電力を得ることができる。一方、Ｕ相、Ｗ相の電機子コイル４，７はＵ，Ｗ接点から単相端子板２２の出力端子Ｕ，Ｗに接続され、またＯ相（図２参照）の電機子コイル５，６は接点Ｏから単相端子板２２の出力端子Ｎに接続されている。そのため、出力端子Ｕ，Ｗ間の出力をとれば２００Ｖの単相３線電力を得ることができ、出力端子Ｕ，Ｎ／Ｎ，Ｗ間の出力をとれば１００Ｖの単相３線電力を得ることができる。こうして３Ｐナイフスイッチ４２を切り替えるだけで、三相端子板２１及び単相端子板２２から同時に三相電力及び単相３線電力を得ることができるようになる。
【００３３】
更に本実施形態では、切替端子板４１のジョイントプレート４５を外して図９に示すように接続することで、高電圧（４００Ｖ）の三相電力のみの使用とすることができる。Ｕ相の電機子コイル１，４とＷ相の電機子コイル３，７とは、それぞれ切替端子板４１の端子Ｕ，Ｗを介して、中性点Ｏ１と三相端子板２１の出力端子Ｒ，Ｔとの間で直列接続される。そして、Ｖ相の電機子コイル２，５，６は、スイッチ４６，４７，４８及び切替端子板４１の端子Ｖを介して、中性点Ｏ１と三相端子板２１の出力端子Ｓとの間で直列接続される。従って、図６に示すように、Ｕ相、Ｖ相、Ｗ相の各電機子コイル１〜７が直列接続され、各相の相電圧によって三相端子板２１の出力端子Ｒ，Ｓ，Ｔから４００Ｖの三相電力を得ることができる。
【００３４】
よって、本実施形態の発電機によれば、高電圧及び低電圧とに切り替えた三相電力のみの使用に加え、更に三相端子板２１及び単相端子板２２から同時に三相電力と単相３線電力を得ることができ、１台で各種の負荷に対応させることができるためより運用コストを抑えることができる。また、切替端子板４１と３Ｐナイフスイッチ４２とによって切り替えを行うため、作業者による切替操作も極めて簡単で、特に低電圧の三相電力のみの使用から使用頻度の多い三相電力と単相３線電力との同時使用には、３Ｐナイフスイッチ４２によって容易に切り替えることができるため使い勝手が良い。更に、三相端子板２１と単相端子板２２を設けているため、切り替えの度に負荷の着脱を行う必要もない。
【００３５】
次に、前記第３実施形態と同様に３パターンの切り替えを可能にした発電機の第４実施形態について説明する。図１０〜図１２は、図１、図２及び図６に示す電機子コイルの接続を切り替える切替手段を含めた、発電機の第３実施形態を示す回路図である。本実施形態は、切り替えに切替端子板５１のみを使用したものである。そこで先ず、図１に示す低電圧（２００Ｖ）の三相電力のみの使用時には、図１０に示すように切替端子板５１によって図示するように接続する。
【００３６】
このときＵ相の電機子コイル１，４とＷ相の電機子コイル３，７とは、中性点Ｏ１と出力端子Ｒ，Ｔとの間に並列に接続される。すなわち、電機子コイル１，３は、その接点Ｘ，Ｚが切替端子板５１のジョイントバー５２を介して各端子Ｘ，Ｚから端子Ｏを経て中性点Ｏ１に接続され、電機子コイル４，７は直接中性点Ｏ１に接続されている。また、電機子コイル１，３は、その接点Ｕ，Ｗが直接三相端子板２１の出力端子Ｒ，Ｔに接続され、電機子コイル４，７は、その接点Ｕ１，Ｗ１が切替端子板５１の各端子Ｕ，Ｗを介して接続されている。
【００３７】
一方、Ｖ相では、電機子コイル５，６の接点Ｙ１，Ｖ２が切替端子板５１の端子Ｐを介して直列接続されている。従ってＶ相では、電機子コイル２と電機子コイル５，６とが、中性点Ｏ１と出力端子Ｓとの間に並列接続される。すなわち、電機子コイル２は、その接点Ｙが切替端子板５１のジョイントバー５２を介して端子Ｙから端子Ｏを経て中性点Ｏ１に接続され、電機子コイル６は、その接点Ｙ２が切替端子板５１の端子Ｏを介して中性点Ｏ１に接続される。また、電機子コイル２は、その接点Ｖが直接三相端子板２１の出力端子Ｓに接続され、電機子コイル５は、その接点Ｖ１が切替端子板５１の端子Ｖを介して出力端子Ｓに接続される。従ってこの場合、図１に示すようにＵ相、Ｖ相、Ｗ相に並列接続された各電機子コイル１〜７に発生する相電圧によって、三相端子板２１の出力端子Ｒ，Ｓ，Ｔから２００Ｖの三相電力を得ることができる。
【００３８】
次に、図２に示すように三相電力（２００Ｖ）と単相３線電力（２００／１００Ｖ）の同時使用を行う場合には、図１１に示すように切替端子板５１によって図示するように接続する。この場合、電機子コイル１，２，３，４，７について接続状態は変わりはない。一方、電機子コイル５，６は、逆方向に並列接続され、中性点Ｏ１と単相端子板２２の出力端子Ｎとの間で結線される。具体的には、出力端子Ｓ側に接続されていた電機子コイル５，６の接点Ｖ１，Ｖ２は、共に切替端子板５１の端子Ｏを介して中性点Ｏ１に接続され、また電機子コイル５の接点Ｙ１は直接、そして電機子コイル６の接点Ｙ２は切替端子板５１の端子Ｐを介して、単相端子板２２の出力端子Ｎに接続される。
【００３９】
従って、Ｕ相、Ｖ相、Ｗ相の電機子コイル１，２，３に発生した相電圧によって、Ｕ，Ｖ，Ｗ接点に接続された三相端子板２１の出力端子Ｒ，Ｓ，Ｔから２００Ｖの三相電力を得ることができる。一方、Ｕ相、Ｗ相の電機子コイル４，７はＵ，Ｗ接点から単相端子板２２の出力端子Ｕ，Ｗに接続され、またＯ相（図２参照）の電機子コイル５，６は接点Ｏから単相端子板２２の出力端子Ｎに接続されている。そのため、出力端子Ｕ，Ｗ間の出力をとれば２００Ｖの単相３線電力を得ることができ、出力端子Ｕ，Ｎ／Ｎ，Ｗ間の出力をとれば１００Ｖの単相３線電力を得ることができる。
【００４０】
更に、高電圧（４００Ｖ）の三相電力のみの使用とする場合には、切替端子板５１のジョイントバー５２を外して図１２に示すように接続する。この場合、Ｕ相の電機子コイル１，４とＷ相の電機子コイル３，７とは、それぞれ切替端子板５１の端子Ｘ，Ｚを介して中性点Ｏ１と三相端子板２１の出力端子Ｒ，Ｔとの間に直列接続される。そして、Ｖ相の電機子コイル２，５，６は、中性点Ｏ１から順に切替端子板５１の端子Ｏ，Ｖ，Ｙを介して出力端子Ｓに直列接続される。従って、図６に示すようにＵ相、Ｖ相、Ｗ相に直列接続された各電機子コイル１〜７に発生する相電圧によって、三相端子板２１の出力端子Ｒ，Ｓ，Ｔから４００Ｖの三相電力を得ることができる。
【００４１】
よって、本実施形態の発電機によれば、高電圧及び低電圧とに切り替えた三相電力のみの使用に加え、更に三相端子板２１及び単相端子板２２から同時に三相電力と単相電力を得ることができ、１台で各種の負荷に対応させることができるためより運用コストを抑えることができる。また、切替端子板５１のみで切り替えを行うため、その構成及び作業者による切替操作も簡単である。更に、三相端子板２１と単相端子板２２を設けているため、切り替えの度に負荷の着脱を行う必要もない。
【００４２】
以上、本発明の発電機について実施形態を示して説明したが、本発明はこれに限定されることなく、その趣旨を逸脱しない範囲で様々な変更が可能である。
【００４３】
【発明の効果】
本発明は、中性点に三相の電機子コイルが星形結線され、三相電力の出力と、切り替えによって単相３線電力の出力とを可能にしたものであって、三相のうち二相は、各相に巻数の等しい二つの電機子コイルを備え、残りの一相は、前記二相におけるものと巻数の等しい電機子コイルを一つと巻数半分の電機子コイルを二つ備え、三相電力のみの使用と三相電力及び単相３線電力の同時使用とを切り替えるようにした切替手段を有する構成としたので、三相電力のみの使用に加えて三相電力及び単相３線電力の同時使用とを切り替えて使用可能にした発電機を提供することが可能となった。
【図面の簡単な説明】
【図１】三相電力のみの使用時における電機子コイルの結線図である。
【図２】三相電力及び単相３線電力同時使用時における結線図である。
【図３】相電圧のベクトル図であり、特に図（ａ）は三相電力の電圧ベクトル図で、図（ｂ）は、単相３線電力の電圧ベクトル図である。
【図４】発電機の第１実施形態を示す回路図である。
【図５】発電機の第２実施形態を示す回路図である。
【図６】高電圧の三相電力のみの使用時における電機子コイルの結線図である。
【図７】図１の状態に電機子コイルを切り替えた発電機の第３実施形態を示す回路図である。
【図８】図２の状態に電機子コイルを切り替えた発電機の第３実施形態を示す回路図である。
【図９】図６の状態に電機子コイルを切り替えた発電機の第３実施形態を示す回路図である。
【図１０】図１の状態に電機子コイルを切り替えた発電機の第４実施形態を示す回路図である。
【図１１】図２の状態に電機子コイルを切り替えた発電機の第４実施形態を示す回路図である。
【図１２】図６の状態に電機子コイルを切り替えた発電機の第４実施形態を示す回路図である。
【図１３】従来の三相電力の切り替えが可能な発電機に使用される電機子コイルの結線図を示したものである。
【図１４】従来の三相電力と単相３線電力の切り替えが可能な発電機に使用される電機子コイルの結線図を示したものである。
【符号の説明】
１〜７電機子コイル
２１三相端子板
２２単相端子板
２３切替端子板
Ｏ１中性点[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a star-connected three-phase AC generator, and more particularly to a generator capable of using only three-phase power and simultaneously using three-phase power and single-phase three-wire power.
[0002]
[Prior art]
Some portable generators used at construction sites and the like are capable of switching the power generation voltage in two stages of 200 V and 400 V, for example, in order to cope with different loads depending on the devices and apparatuses to be operated. FIG. 13 is a connection diagram of armature coils used in the generator. This generator is configured so that the voltage of the three-phase power can be switched. Specifically, as shown in the figure, the generator is constituted by two armature coils 101 to 106 for each of the U phase, the V phase, and the W phase. However, the switching terminal plate (not shown) can be switched between FIG. 13 (a) and FIG. 13 (b). Therefore, if the armature coils 101 to 106 in each phase are connected in series as shown in FIG. 13A, high-phase (for example, 400 V) three-phase power can be obtained, and the connection of the terminals is switched to change the connection shown in FIG. If it is connected in parallel as shown in (3), three-phase power of low voltage (for example, 200V) can be obtained.
[0003]
On the other hand, in addition to such switching of the three-phase power, there is one that switches between the three-phase power and the single-phase three-wire power. FIG. 14 shows a connection diagram of armature coils used in such a generator. This is configured by splitting only the V phase of the U-phase, V-phase, and W-phase armature coils 201 to 204, and switching between FIG. 14 (a) and FIG. 14 (b) using a switching terminal plate (not shown). It is intended to be. Therefore, if the armature coils 202 and 203 are connected in series as shown in FIG. 14 (a), three-phase power (for example, 200V) can be obtained, and the connection of the terminals is switched and the V-phase as shown in FIG. 14 (b). If the armature coil 203 is connected in the opposite direction with respect to the neutral point, single-phase three-wire power (for example, 100 V) can be obtained.
[0004]
[Problems to be solved by the invention]
However, the output obtained by switching in the conventional generator is only a single voltage such as three-phase 200V, three-phase 400V, and single-phase 100V as described above. On the other hand, at construction sites, generators are used with single-phase 200V or single-phase 100V as power sources for electric tools or electric equipment in field offices, for example, and three-phase 200V as power sources for submersible pumps and welding machines. Often used in. Since there are multiple types of power sources for such loads at construction sites, it has conventionally been necessary to prepare separate power sources for loads with different power specifications or to use a transformer or the like.
[0005]
Specifically, in order to use a three-phase 200V load and a single-phase 100V load at the same time, in addition to a three-phase 200V output generator, armature coils 201-204 are connected as shown in FIG. It is necessary to prepare another generator of single phase 100V, or to convert the output of the generator connected to armature coils 201 to 204 to single phase 100V by a transformer or the like as shown in FIG. For this reason, when three-phase power and single-phase three-wire power are required, a separate generator or transformer is required, and the operation cost has been high at conventional construction sites.
Furthermore, when switching to obtain single-phase three-wire power as shown in FIG. 14B, the armature coil 202 was not used, so that the generator's original power generation capacity could not be utilized. There was waste.
[0006]
Therefore, in order to solve the problem, the present invention aims to provide a generator that can be used by switching between simultaneous use of three-phase power and single-phase three-wire power in addition to use of only three-phase power. And
[0007]
[Means for Solving the Problems]
In the generator of the present invention, a three-phase armature coil is star-connected to the neutral point, and the output of the three-phase power There is a switching means capable of switching the connection state with the output of single-phase three-wire power, and the three-phase armature coil has a first phase and a second phase. Each phase has two armature coils with the same number of turns, The third phase Above Phase 1 and Phase 2 In Armature coil and Equal number of turns Same volume One armature coil and half the number of turns Half volume Two armature coils In the case of an output with only three-phase power, the switching means may connect the armature coils of each phase in series between the neutral point and the output terminal, or make the number of turns equal. In the case of three-phase power and single-phase three-wire power output in parallel, the first-phase and second-phase armature coils are connected in parallel between the neutral point and the output terminal, and the third The half-turn armature coils in the phase are arranged in parallel and the phase of the half-turn armature coil is shifted by 180 degrees, and the half-turn armature coil and the same-turn armature coil are respectively placed between the neutral point and the output terminal. Must be switched to connect It is characterized by.
[0009]
Therefore, according to the present invention, two armature coils having the same number of turns are provided for two phases, and one armature coil that is the same as these and one armature coil having half the number of turns are provided for the remaining one phase. Since there are two, the switching means first sets the armature coils of each phase in series between the neutral point and the output terminal or in parallel with the same number of turns. It is possible to switch and output three-phase power of voltage and low voltage. Next, a two-phase armature coil is connected in parallel between the neutral point and the output terminal, and the armature coil having half the number of turns in the remaining one phase is opposite to the armature coil having the same number of turns and in parallel. If each is connected between the neutral point and the output terminal, three-phase power and single-phase three-wire power can be output simultaneously.
[0010]
In the generator according to the present invention, the switching unit can switch the use of only the three-phase power and the simultaneous use of the three-phase power and the single-phase three-wire power by changing the connection to the terminal. It is the switching terminal board which performs.
Further, in the generator of the present invention, the switching means includes the switching terminal plate, Phase 3 In Half-turn armature coil The connection Phase 3 In Same armature coil Against In phase When connecting in series Shift the phase by 180 degrees It is characterized by having a knife switch that switches between parallel connection and connection.
Therefore, according to the present invention, since it can be switched by the switching terminal board as in the prior art, it is easy to use without any change from the conventional switching operation. Moreover, if a knife switch is used, it can be easily switched to simultaneous use of three-phase power and single-phase three-wire power, which is convenient.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Next, an embodiment of a generator according to the present invention will be described below with reference to the drawings. The generator of the present embodiment enables the use of only three-phase power and the simultaneous use of three-phase power and single-phase three-wire power. FIG. 1 shows the case of using only three-phase power (200 V). FIG. 2 is a connection diagram of an armature coil, and FIG. 2 is a connection diagram when three-phase power (200 V) and single-phase three-wire power (200/100 V) are used simultaneously. Specifically, when only the three-phase power shown in FIG. 1 is used, U-phase, V-phase, and W-phase armature coils 1 to 7 are star-connected to the neutral point O1, and the U-phase, V-phase, A pair of armature coils having the same number of turns in the W phase are connected in parallel between the neutral point O1 and the contacts U, V, W. In particular, in the V phase, one armature coil 5, 6 divided in half with one half the number of turns is connected in series.
[0012]
Here, FIG. 3 shows FIG. as well as FIG. 3 is a vector diagram of phase voltages shown in FIG. 2. 3A is a voltage vector diagram of the three-phase power, and FIG. 3B is a voltage vector diagram of the single-phase three-wire power. In the generator in which the armature coils 1 to 7 are star-connected as shown in FIG. 1, the phases shown in FIG. Voltages Eu, Ev, Ew are generated. Between the output terminals of each phase, a line voltage of a symmetrical three-phase AC voltage having the same magnitude and a phase difference of 120 ° is obtained by the phase voltages Eu, Ev, Ew. The line voltage is √3 times the phase voltage. A line voltage of 200 V is generated with respect to the phase voltage of 115 V, and three-phase power of 200 V is obtained.
[0013]
Next, when the three-phase power and the single-phase three-wire power shown in FIG. 2 are used simultaneously, the connection of the V-phase armature coils 5 and 6 is switched. In the generator thus switched, the V-phase armature coil 2 and the respective one of the U-phase and W-phase armature coils 1 and 3 are star-connected. On the other hand, the half-turned armature coils 5 and 6 are connected in parallel in the direction opposite to that shown in FIG. 1, and the other armature coils 4 and 7 are V-connected in the U phase and the W phase. Has been. Therefore, in this case, the voltage vectors by the armature coils 1, 2, 3 of the respective phases connected in a star shape are as shown in FIG. 3A, and the V-phase armature coils 5, 6 and the U-phase FIG. 3B shows a voltage vector generated by the W-phase armature coils 4 and 7.
[0014]
The voltage vector shown in FIG. 3A is one for each phase. One by one Phase voltages Eu, Ev, and Ew generated by the armature coils 1, 2, and 3 having the same magnitude and different phases by 120 °. Therefore, even after switching, a line voltage of a symmetrical three-phase AC voltage can be obtained between the output terminals of the armature coils 1, 2 and 3 as in the case of using only the three-phase power shown in FIG. The line voltage is √3 times the phase voltage. A line voltage of 200 V is generated with respect to the phase voltage of 115 V, and three-phase power of 200 V is obtained. However, in this case, since the V-phase armature coil is reduced to one, the power is reduced to ½.
[0015]
On the other hand, the voltage vectors shown in FIG. 3B are the phase voltages Eu and Ew by the U-phase and W-phase armature coils 4 and 7 and the phase voltage Eo by the O-phase armature coils 5 and 6. Here, the phase voltage Eo has the number of turns of the armature coils 5 and 6 and is connected in the opposite direction, so that the phase is inverted at the voltage 1/2. Therefore, if the output between the output terminals of the armature coils 4 and 7 is taken, a single-phase three-wire power of 200 V is obtained, and the output between the output terminals of the armature coils 5 and 6 and the armature coils 4 and 7 is obtained. In this case, 100V single-phase three-wire power can be obtained.
[0016]
Therefore, in the generator of this embodiment consisting of the armature coils 1 to 7, if the connection is switched as shown in FIGS. 1 and 2, only the three-phase power can be obtained as shown in FIG. If switched as shown in FIG. 2, 200V or 100V single-phase three-wire power can be obtained simultaneously with the three-phase power. Therefore, it is not necessary to prepare a separate generator or use a transformer, etc., so that one generator can be used simultaneously as a power source for loads corresponding to three-phase power and single-phase three-wire power. There are no operational costs. Furthermore, since three-phase power and single-phase three-wire power are used at the same time, the armature coil that does not function is eliminated, and the power generator can be fully utilized.
[0017]
Subsequently, the configuration including the switching means will be described below with respect to the generator including the armature coils 1 to 7. FIG. 4 is a circuit diagram showing a first embodiment of the generator including switching means for switching the connection of the armature coils in the state shown in FIGS. 1 and 2. Here, U-phase, V-phase, and W-phase armature coils 1, 2, 3, 4, and 7 are connected between a neutral point O1 and each of the contacts U, V, and W, as shown, The contacts O1, U, V, and W are connected to a three-phase terminal plate 21 that extracts three-phase power, and the contacts U and W are further connected to a single-phase terminal plate 22 that extracts single-phase three-wire power. On the other hand, the V-phase armature coils 5 and 6 are connected to the three-phase terminal plate 21 and the single-phase terminal plate 22 from the neutral point O1 and the contacts O and V via the switching terminal plate 23. 1 and 2 are switched by short-circuit plates 25, 26, and 27. In the connection state indicated by solid lines, armature coils 5 and 6 are connected as shown in FIG. The connection is made as shown in FIG. 2 in the state indicated by the chain line.
[0018]
Therefore, when only the three-phase power shown in FIG. 1 is used, the short-circuit plates 25, 26 and 27 of the switching terminal plate 23 are connected as shown by the solid line in FIG. At this time, the V-phase armature coils 5 and 6 are connected at their contacts V2 and Y1 via the short-circuit plate 25, and the contact V1 of the armature coil 5 is connected to the contact V via the short-circuit plate 26 and the armature. The contact Y2 of the coil 6 is connected to the neutral point O1 through the short-circuit plate 27. Therefore, the armature coils 5 and 6 are connected in series and in parallel with the armature coil 2 between the neutral point O1 and the contact V. On the other hand, the U-phase armature coils 1 and 4 and the W-phase armature coils 3 and 7 are connected in parallel between the neutral point O1 and the contacts U and W, respectively. Therefore, in this case, the armature coils 1 to 7 are connected as shown in FIG. 1, and three-phase power is obtained from the output terminals R, S, and T of the three-phase terminal plate 21 connected to the U, V, and W contacts. be able to.
[0019]
Next, as shown in FIG. 2, when three-phase power and single-phase three-wire power are used at the same time, the short-circuit plates 25, 26, and 27 of the switching terminal plate 23 are indicated by the one-dot chain line in FIG. Can be switched. At this time, the contact V1 of the V-phase armature coil 5 is connected from the terminal V1-V1 of the switching terminal plate 23 to the neutral point O1 via the short-circuit plate 27, and the contact V2 of the armature coil 6 is switched. The terminal V23 is connected to the neutral point O1 through the terminal V2-V2 and the shorting plate 26, and similarly from the terminal V1-V1 through the shorting plate 27. On the other hand, the armature coil 5 has the contact Y1 connected to the contact O from the short-circuit plate 25 via the terminals Y2-Y2, and the armature coil 6 has the contact Y2 directly connected to the contact O. Thus, the armature coils 5 and 6 are connected in the opposite direction to that before the switching described above. And about the other armature coils 1, 2, 3, 4, and 7, there is no change in the connection state.
[0020]
Therefore, in this case, the armature coils 1 to 7 are connected as shown in FIG. 2, and the U, V, and W contacts are brought into contact by the phase voltages generated in the U-phase, V-phase, and W-phase armature coils 1, 2, and 3. Three-phase power can be obtained from the output terminals R, S, T of the connected three-phase terminal board 21. The U-phase and W-phase armature coils 4 and 7 are connected to the output terminals U and W of the single-phase terminal plate 22 through their U and W contacts, and the O-phase (see FIG. 2) armature coil 5. , 6 are connected from the contact O to the output terminal N. Therefore, if the output between the output terminals U and W is taken, 200V single-phase three-wire power can be obtained, and if the output between the output terminals U, N / U, and W is taken, 100V single-phase three-wire power is obtained. be able to.
[0021]
Therefore, according to the generator of this embodiment, by switching the short-circuit plates 25, 26, and 27 of the switching terminal plate 23, in addition to the output of only the three-phase power, the three-phase terminal plate 21 and the single-phase terminal plate 22 simultaneously. Three-phase power and single-phase three-wire power can be obtained. Therefore, it is not necessary to attach or detach the load every time switching is performed. In this case, since the switching can be performed only by the short-circuit plates 25, 26, and 27 of the switching terminal plate 21, the switching operation is also easy. Here, if a changeover switch such as a knife switch is used instead of the changeover terminal plate 23, the operation is further facilitated.
[0022]
Next, FIG. 5 is a circuit diagram showing a second embodiment of the generator including switching means for switching the connection of the armature coils in the state shown in FIGS. 1 and 2. In the present embodiment, since only the switching terminal plate is different from that shown in FIG. 4, the same components are denoted by the same reference numerals and description thereof is omitted. In this embodiment, the switching terminal plate 30 performs the switching of FIGS. 1 and 2, and the armature coils 1 to 7 can be connected as shown in FIG. 1 when the short-circuit plates 31, 32, 33 are in the connection state indicated by the solid line, In the case of the connection state indicated by the alternate long and short dash line, the connection can be made as shown in FIG.
[0023]
Therefore, first, as shown in FIG. 1, when only three-phase power is used, the short-circuit plates 31, 32 and 33 are connected as shown by the solid line in FIG. At this time, the V-phase armature coils 5 and 6 have their contacts V2 and Y1 connected in series via the short-circuit plate 31, and the contact V1 of the armature coil 5 is connected to the contact V via the short-circuit plate 32 and The contact Y2 of the armature coil 6 is connected to the neutral point O1 via the short-circuit plate 33. Therefore, the armature coils 5 and 6 are connected in series between the neutral point O1 and the contact point V and in parallel with the armature coil 2. On the other hand, the U-phase armature coils 1 and 4 and the W-phase armature coils 3 and 7 are connected in parallel between the neutral point O1 and the contacts U and W, respectively. Therefore, in this case, the armature coils 1 to 7 are connected as shown in FIG. 1, and three-phase power is obtained from the output terminals R, S, and T of the three-phase terminal plate 21 connected to the U, V, and W contacts. be able to.
[0024]
Next, when the three-phase power and the single-phase three-wire power are used simultaneously as shown in FIG. 2, the short-circuit plates 31, 32, and 33 of the switching terminal plate 30 are switched as shown by the one-dot chain line in FIG. 5. . At this time, the V-phase armature coil 5 has its contact point V1 connected to the neutral point O1 via the short-circuit plate 33, and the armature coil 6 has its contact point V2 neutral point via the short-circuit plates 32 and 33. Connected to O1. On the other hand, the armature coil 5 has its contact Y1 connected to the contact O from the short-circuit plate 31 via terminals Y1-Y2, and the armature coil 6 has its contact Y2 connected directly to the contact O. Thus, the armature coils 5 and 6 are connected in the opposite direction to that before the switching described above. And about the other armature coils 1, 2, 3, 4, and 7, there is no change in the connection state.
[0025]
Therefore, in this case, the armature coils 1 to 7 are connected as shown in FIG. 2, and the U, V, and W contacts are brought into contact by the phase voltages generated in the U-phase, V-phase, and W-phase armature coils 1, 2, and 3. Three-phase power can be obtained from the output terminals R, S, T of the connected three-phase terminal board 21. The U-phase and W-phase armature coils 4 and 7 are connected to the output terminals U and W of the single-phase terminal plate 22 through their U and W contacts, and the O-phase (see FIG. 2) armature coil 5. , 6 are connected from the contact O to the output terminal N. Therefore, if the output between the output terminals U and W is taken, 200V single-phase power can be obtained, and if the output between the output terminals U, N / N, and W is taken, 100V single-phase power can be obtained.
[0026]
Therefore, according to the generator of this embodiment, by switching the short-circuit plates 31, 32, 33 of the switching terminal plate 30, in addition to the output of only the three-phase power, the three-phase terminal plate 21 and the single-phase terminal plate 22 simultaneously. Three-phase power and single-phase three-wire power can be obtained. Therefore, it is not necessary to attach or detach the load every time switching is performed. In this case, since the switching can be performed only by the short-circuit plates 31, 32, 33 of the switching terminal plate 30, the switching operation is also easy.
[0027]
By the way, in the generator of the said embodiment, if three-phase electric power is dedicated for 200V, the simultaneous use of 200V three-phase electric power and 200V or 100V single-phase three-wire electric power will be attained. However, at the construction site and the like, as described in the conventional example of FIG. 13, there is a demand for a generator capable of switching the output of the high voltage (400V) in addition to the low voltage (200V). Therefore, in the present embodiment, a generator that can use only high-voltage three-phase power will be described. FIG. 6 is a connection diagram of the armature coils when only high-voltage three-phase power is used, and the connection of the armature coils 1 to 7 shown in FIGS. 1 and 2 is switched. When only high-voltage three-phase power is used, the armature coils 1 to 7 are connected in series for each phase as shown in FIG. At this time, in the U-phase, V-phase, and W-phase that are star-connected, phase voltages that are equal in magnitude and different in phase from each other by 120 ° are generated in the same manner as shown in FIG. Between terminals, a line voltage of a symmetrical three-phase AC voltage having the same magnitude depending on the phase voltage and a phase difference of 120 ° is obtained. The line voltage is √3 times the phase voltage, and a line voltage of 400 V is generated with respect to the phase voltage of 230 V, and a three-phase power of 400 V is obtained.
[0028]
Subsequently, a generator that enables the switching of three patterns of the use of only the low voltage three-phase power and the simultaneous use of the three-phase power and the single-phase three-wire power by adding the use of the high-voltage three-phase power only. Will be described. FIGS. 7 to 9 are circuit diagrams showing a third embodiment of the generator including switching means for switching the connection of the armature coils in the states shown in FIGS. 1, 2 and 6. Here, in addition to the switching terminal board 41, the 3P knife switch 42 is used for switching. First, when using only the low-voltage (200V) three-phase power shown in FIG. 1, as shown in FIG. 7, the switching terminal plate 41 and the 3P knife switch are connected as shown.
[0029]
At this time, the U-phase armature coils 1 and 4 and the W-phase armature coils 3 and 7 are connected in parallel between the neutral point O1 and the output terminals R and T of the three-phase terminal plate 21. That is, the contact points X and Z of the armature coils 1 and 3 are connected from the terminals X and Z to the neutral point O1 via the joint bar 45 of the switching terminal plate 41 to the neutral point O1. 7 is directly connected to the neutral point O1. The armature coils 1 and 3 have their contacts U and W connected directly to the output terminals R and T, and the armature coils 4 and 7 have their contacts U1 and W1 connected to the switching terminal plate 41. Through Each terminal U, W In Connected.
[0030]
On the other hand, in the V phase, the contacts Y 1 and V 2 of the armature coils 5 and 6 are connected in series via the switch 47 of the 3P knife switch 42. Therefore, in the V phase, the armature coil 2 and the armature coils 5 and 6 are connected in parallel between the neutral point O1 and the output terminal S of the three-phase terminal plate 21. That is, the contact point Y of the armature coil 2 is connected from the terminal Y to the neutral point O1 via the joint bar 45 of the switching terminal plate 41, and the contact point Y2 of the armature coil 6 is the switch 46. Connected through. The armature coil 2 has its contact V directly connected to the output terminal S, and the armature coil 5 has its contact V1 connected via the switch 48 via the terminal V of the switching terminal plate 41. Therefore, in this case, the output terminals R, S, T of the three-phase terminal plate 21 are generated by the phase voltages generated in the armature coils 1 to 7 connected in parallel to the U phase, the V phase, and the W phase as shown in FIG. 200V three-phase power can be obtained.
[0031]
Next, as shown in FIG. 2, when simultaneous use of three-phase power (200V) and single-phase three-wire power (200 / 100V) is performed, the switching terminal plate 41 and 3P knife switch are used as shown in FIG. Connect as shown. In this case, there is no change in the connection of the switching terminal plate 41, and there is no change in the connection state of the armature coils 1, 2, 3, 4, 7. On the other hand, since the 3P knife switch 42 is switched, the armature coils 5 and 6 are connected in parallel in the reverse direction. Specifically, the contacts V1, V2 of the armature coils 5, 6 connected to the output terminal S side are connected to the neutral point O1 via the switches 48, 47, and the contact Y1 of the armature coil 5 is connected. Is directly connected to the output terminal N of the single-phase terminal plate 22, and the contact Y <b> 2 of the armature coil 6 is connected via the switch 46.
[0032]
Therefore, from the output terminals R, S, and T of the three-phase terminal plate 21 connected to the U, V, and W contacts by the phase voltages generated in the U-phase, V-phase, and W-phase armature coils 1, 2, and 3. 200V three-phase power can be obtained. On the other hand, the U-phase and W-phase armature coils 4 and 7 are connected from the U and W contacts to the output terminals U and W of the single-phase terminal plate 22, and the O-phase (see FIG. 2) armature coils 5 and 6. Is connected from the contact O to the output terminal N of the single-phase terminal plate 22. Therefore, if the output between the output terminals U and W is taken, 200V single-phase three-wire power can be obtained, and if the output between the output terminals U, N / N, and W is taken, 100V single-phase three-wire power is obtained. be able to. Thus, it is possible to simultaneously obtain three-phase power and single-phase three-wire power from the three-phase terminal plate 21 and the single-phase terminal plate 22 by simply switching the 3P knife switch 42.
[0033]
Further, in the present embodiment, by removing the joint plate 45 of the switching terminal plate 41 and connecting it as shown in FIG. 9, it is possible to use only high-voltage (400 V) three-phase power. The U-phase armature coils 1 and 4 and the W-phase armature coils 3 and 7 are connected to the neutral point O1 and the output terminal R of the three-phase terminal plate 21 via the terminals U and W of the switching terminal plate 41, respectively. , T are connected in series. The V-phase armature coils 2, 5, 6 are connected between the neutral point O 1 and the output terminal S of the three-phase terminal plate 21 via the switches 46, 47, 48 and the terminal V of the switching terminal plate 41. Are connected in series. Therefore, as shown in FIG. 6, the U-phase, V-phase, and W-phase armature coils 1 to 7 are connected in series, and output from the output terminals R, S, and T of the three-phase terminal plate 21 by the phase voltage of each phase. 400V three-phase power can be obtained.
[0034]
Therefore, according to the generator of the present embodiment, in addition to the use of only the three-phase power switched to the high voltage and the low voltage, the three-phase power and the single-phase are simultaneously transmitted from the three-phase terminal plate 21 and the single-phase terminal plate 22. Three-wire power can be obtained, and the operation cost can be further reduced because one unit can cope with various loads. In addition, since the switching is performed by the switching terminal board 41 and the 3P knife switch 42, the switching operation by the operator is extremely simple. Particularly, the three-phase power and the single-phase 3 that are frequently used since only the low-voltage three-phase power is used. Simultaneous use with line power is easy to use because it can be easily switched by the 3P knife switch 42. Furthermore, since the three-phase terminal board 21 and the single-phase terminal board 22 are provided, it is not necessary to attach or detach the load each time switching is performed.
[0035]
Next, a description will be given of a fourth embodiment of the generator that enables switching between three patterns as in the third embodiment. FIGS. 10-12 is a circuit diagram which shows 3rd Embodiment of a generator including the switching means which switches the connection of the armature coil shown in FIG.1, FIG2 and FIG.6. In the present embodiment, only the switching terminal board 51 is used for switching. Therefore, first, when using only the low-voltage (200V) three-phase power shown in FIG. 1, the connection is made as shown by the switching terminal plate 51 as shown in FIG.
[0036]
At this time, the U-phase armature coils 1 and 4 and the W-phase armature coils 3 and 7 are connected in parallel between the neutral point O1 and the output terminals R and T. That is, the contact points X and Z of the armature coils 1 and 3 are connected from the terminals X and Z to the neutral point O1 via the joint bar 52 of the switching terminal plate 51 to the neutral point O1. 7 is directly connected to the neutral point O1. The armature coils 1 and 3 have their contacts U and W directly connected to the output terminals R and T of the three-phase terminal plate 21, and the armature coils 4 and 7 have their contacts U 1 and W 1 at the switching terminal plate 51. Are connected via the terminals U and W.
[0037]
On the other hand, in the V phase, the contacts Y 1 and V 2 of the armature coils 5 and 6 are connected in series via the terminal P of the switching terminal plate 51. Therefore, in the V phase, the armature coil 2 and the armature coils 5 and 6 are connected in parallel between the neutral point O1 and the output terminal S. That is, the contact point Y of the armature coil 2 is connected from the terminal Y to the neutral point O1 via the joint bar 52 of the switching terminal plate 51, and the contact point Y2 of the armature coil 6 is switched to the switching terminal. The terminal 51 of the plate 51 is connected to the neutral point O1. The armature coil 2 has its contact V directly connected to the output terminal S of the three-phase terminal plate 21, and the armature coil 5 has its contact V 1 connected to the output terminal S via the terminal V of the switching terminal plate 51. Connected. Therefore, in this case, the output terminals R, S, T of the three-phase terminal plate 21 are generated by the phase voltages generated in the armature coils 1 to 7 connected in parallel to the U phase, the V phase, and the W phase as shown in FIG. 200V three-phase power can be obtained.
[0038]
Next, as shown in FIG. 2, when simultaneous use of three-phase power (200V) and single-phase three-wire power (200 / 100V) is performed, as shown in FIG. Connecting. In this case, the connection state of the armature coils 1, 2, 3, 4, 7 is not changed. On the other hand, the armature coils 5 and 6 are connected in parallel in the opposite direction, and are connected between the neutral point O1 and the output terminal N of the single-phase terminal plate 22. Specifically, the contacts V1, V2 of the armature coils 5, 6 connected to the output terminal S side are both connected to the neutral point O1 via the terminal O of the switching terminal plate 51, and the armature coil. The contact Y1 of 5 is connected directly, and the contact Y2 of the armature coil 6 is connected to the output terminal N of the single-phase terminal plate 22 via the terminal P of the switching terminal plate 51.
[0039]
Therefore, from the output terminals R, S, and T of the three-phase terminal plate 21 connected to the U, V, and W contacts by the phase voltages generated in the U-phase, V-phase, and W-phase armature coils 1, 2, and 3. 200V three-phase power can be obtained. On the other hand, the U-phase and W-phase armature coils 4 and 7 are connected from the U and W contacts to the output terminals U and W of the single-phase terminal plate 22, and the O-phase (see FIG. 2) armature coils 5 and 6. Is connected from the contact O to the output terminal N of the single-phase terminal plate 22. Therefore, if the output between the output terminals U and W is taken, 200V single-phase three-wire power can be obtained, and if the output between the output terminals U, N / N, and W is taken, 100V single-phase three-wire power is obtained. be able to.
[0040]
Further, when only the high-voltage (400 V) three-phase power is used, the joint bar 52 of the switching terminal plate 51 is removed and connected as shown in FIG. In this case, the U-phase armature coils 1 and 4 and the W-phase armature coils 3 and 7 are respectively connected to the neutral point O1 and the three-phase terminal plate 21 via the terminals X and Z of the switching terminal plate 51. The terminals R and T are connected in series. The V-phase armature coils 2, 5, 6 are connected in series to the output terminal S via the terminals O, V, Y of the switching terminal plate 51 in order from the neutral point O 1. Therefore, as shown in FIG. 6, 400 V from the output terminals R, S, and T of the three-phase terminal plate 21 is generated by the phase voltage generated in each of the armature coils 1 to 7 connected in series to the U phase, V phase, and W phase. The three-phase power can be obtained.
[0041]
Therefore, according to the generator of the present embodiment, in addition to the use of only the three-phase power switched to the high voltage and the low voltage, the three-phase power and the single-phase are simultaneously transmitted from the three-phase terminal plate 21 and the single-phase terminal plate 22. Since electric power can be obtained and various loads can be handled by a single unit, operation costs can be further reduced. Further, since the switching is performed only by the switching terminal board 51, the configuration and the switching operation by the operator are simple. Furthermore, since the three-phase terminal board 21 and the single-phase terminal board 22 are provided, it is not necessary to attach or detach the load each time switching is performed.
[0042]
As mentioned above, although the generator was demonstrated and demonstrated about this invention, this invention is not limited to this, A various change is possible in the range which does not deviate from the meaning.
[0043]
【The invention's effect】
In the present invention, a three-phase armature coil is star-connected at a neutral point, and three-phase power output and single-phase three-wire power output by switching are possible. Two phases are provided with two armature coils having the same number of turns in each phase, and the remaining one phase is provided with one armature coil having the same number of turns as that in the two phases and two armature coils having a half number of turns, Since the switching means is configured to switch between the use of only three-phase power and the simultaneous use of three-phase power and single-phase three-wire power, in addition to using only three-phase power, three-phase power and single-phase three It has become possible to provide a generator that can be used by switching between simultaneous use of line power.
[Brief description of the drawings]
FIG. 1 is a connection diagram of armature coils when only three-phase power is used.
FIG. 2 is a connection diagram at the time of simultaneous use of three-phase power and single-phase three-wire power.
3A and 3B are vector diagrams of phase voltages, in particular, FIG. 3A is a voltage vector diagram of three-phase power, and FIG. 3B is a voltage vector diagram of single-phase three-wire power.
FIG. 4 is a circuit diagram showing a first embodiment of a generator.
FIG. 5 is a circuit diagram showing a second embodiment of the generator.
FIG. 6 is a connection diagram of armature coils when only high-voltage three-phase power is used.
FIG. 7 is a circuit diagram showing a third embodiment of the generator in which the armature coil is switched to the state shown in FIG. 1;
FIG. 8 is a circuit diagram showing a third embodiment of the generator in which the armature coil is switched to the state shown in FIG. 2;
FIG. 9 is a circuit diagram showing a third embodiment of the generator in which the armature coil is switched to the state of FIG. 6;
FIG. 10 is a circuit diagram showing a fourth embodiment of the generator in which the armature coil is switched to the state shown in FIG. 1;
FIG. 11 is a circuit diagram showing a fourth embodiment of the generator in which the armature coil is switched to the state shown in FIG. 2;
12 is a circuit diagram showing a fourth embodiment of the generator in which the armature coil is switched to the state shown in FIG. 6; FIG.
FIG. 13 is a connection diagram of armature coils used in a conventional generator capable of switching three-phase power.
FIG. 14 is a connection diagram of armature coils used in a generator capable of switching between conventional three-phase power and single-phase three-wire power.
[Explanation of symbols]
1-7 Armature coil
21 Three-phase terminal board
22 Single-phase terminal board
23 Switching terminal board
O1 neutral point

Claims

A three-phase armature coil is star-connected to the neutral point, and has a switching means capable of switching the connection state between the output of the three-phase power and the output of the single-phase three-wire power,
Armature coils of the three phases, the first phase and the second phase comprises two armature coils equal number of turns in each phase, the armature coils and the number of turns of the third phase is definitive in the first and second phases are those having two half volume armature coils equal in the same winding the armature coils one and turns half,
The switching means is
In the case of the output of only three-phase power, the armature coils of each phase are connected in series between the neutral point and the output terminal, or connected in parallel with the same number of turns.
In the case of the output of three-phase power and single-phase three-wire power, the first-phase and second-phase armature coils are connected in parallel between the neutral point and the output terminal, and the half-winding in the third phase The armature coils are arranged in parallel and the phase of the armature coil is shifted by 180 degrees so that the half-turn armature coil and the same-turn armature coil are connected between the neutral point and the output terminal, respectively. A generator characterized by switching .

The generator according to claim 1 ,
The switching means is a switching terminal plate that achieves switching between the use of only the three-phase power and the simultaneous use of the three-phase power and the single-phase three-wire power by changing the connection to the terminal. And the generator.

The generator according to claim 2 ,
In addition to the switching terminal plate, the switching means has a phase in which the connection of the half- turn armature coil in the third phase is connected in series with the same armature coil in the third phase in the same phase. A generator having a knife switch for switching between a case of being shifted in parallel by 180 degrees .