JP2004036993A

JP2004036993A - Controlling method and device for refrigerant compressor

Info

Publication number: JP2004036993A
Application number: JP2002194511A
Authority: JP
Inventors: Takao Noguchi; 野口　孝男; Nobuo Endo; 遠藤　宣夫
Original assignee: Kokan Kikai Kogyo KK
Current assignee: Kokan Kikai Kogyo KK
Priority date: 2002-07-03
Filing date: 2002-07-03
Publication date: 2004-02-05

Abstract

<P>PROBLEM TO BE SOLVED: To provide a control device for a refrigerant compressor and its controlling method capable of achieving a power saving in a target temperature regulation control of the refrigerant compressor in a refrigerator or an air conditioner and of maintaining a certain temperature range even when a turbulence to bring about an abnormal temperature change is generated. <P>SOLUTION: The control device of the refrigerant compressor equipped with a target temperature regulation controlling means to actually measure the temperature of any object to be air conditioned and control the refrigerant compressor to the preset target temperature is furnished with an upper and lower limit temperature setting means to set previously the upper and lower limit temperatures of the object, a first actually measured temperature comparative judging means to compare the upper and lower limit temperatures with the actually measured temperature of the object and pass a judgement, an operation control mode changeover means for the compressor to change over between the On-Off control mode of the compressor and the target temperature regulation control mode on the basis of the result from comparative judgement of the actually measured temperature, and a second actually measured temperature comparative judging means to make comparative judgement of the upper and lower limit temperatures with the actually measured temperature of the object at the preset time intervals during the operation control in the target temperature regulation control mode. <P>COPYRIGHT: (C)2004,JPO

Description

【０００１】
【発明の属する技術分野】
本発明は、冷凍機や空調機などに内蔵される冷媒圧縮機（コンプレッサー）の制御装置及び制御方法に関するものである。
【０００２】
【従来の技術】
冷凍機や空調機には、冷媒圧縮機が内蔵されている。そして、冷凍機での冷却運転や空調機での冷房運転及び暖房運転などでは、空調対象が予め設定した目標温度となるように、この冷媒圧縮機の駆動や停止を制御している。ここで、空調対象とは、冷凍庫や冷蔵庫、あるいはホール，オフィス，一般家庭の室内など、冷凍，冷蔵，冷房，暖房のいずれかを必要とする空間のことであり、目標温度の高低や空間の大きさなどは問わない。
【０００３】
このような、予め設定した目標温度となるように圧縮機を制御する方法（以下、目標温度調節制御と呼ぶ）は、最も一般的な圧縮機の制御方法であり、現在広く用いられている。しかし、これらの圧縮機は電力使用量が大きいため、省電力化が求められており、これまでに様々な省電力化の検討が行われてきた。
【０００４】
このような省電力化の方法の一つに、オン／オフ制御と呼ばれる方法がある。オン／オフ制御とは、空調対象の目標温度や実際の温度にかかわらず、圧縮機の駆動／停止を周期的に繰り返す断続運転（間欠運転）を行うものである。すなわち、圧縮機を所定時間Ｔ１の間駆動したら、所定時間Ｔ２の間停止し、再び駆動する、というサイクルを周期的に繰り返す。例えば、駆動時間Ｔ１を１０分、停止時間Ｔ２を５分とすれば、圧縮機は１／３の時間は停止していることとなる。したがって、オン／オフ制御によれば、空調対象の温度（室温など）にかかわらず、圧縮機の駆動を一定時間強制的に停止するため、圧縮機の駆動時間を短縮することとなり、省電力化を図ることができる。
【０００５】
【発明が解決しようとする課題】
しかし、このオン／オフ制御には、以下のような問題がある。
【０００６】
例えば、室内の空調機による冷房運転を例にとると、オン／オフ制御では、室温にかかわらず圧縮機を一定時間停止するため、圧縮機の停止中に、室温が目標温度よりも上昇する場合がある。そして、その後の圧縮機の駆動時間内に温度が目標温度まで下がれば問題はないが、目標温度まで到達しない場合には、再び圧縮機が停止して室温はさらに高くなる。このように、一般にオン／オフ制御では目標温度よりもやや高目の温度となるが、場合によっては室温が異常に上昇してしまうこともあり得る。
【０００７】
このような異常な温度上昇は、冷房対象の熱負荷と比較して、圧縮機の停止時間が長すぎることに起因して発生する。通常は、このような問題が生じないように、オン／オフ時間の比（デューティー比）が設定されている。しかし、外気温度の異常上昇や、室内の人や物の出入量や在庫量が異常に多い場合、室内の発熱体が異常に発熱した場合など、想定していない異常な事態（外乱）が生じると、このような問題が生じる場合がある。そして、その結果として、冷凍，冷蔵，冷房対象の物品に対して品質的，性能的なダメージを与えたり、室内の人に不快感を与えていた。
【０００８】
本発明の目的は、冷凍機や空調機などにおける冷媒圧縮機の目標温度調節制御における省電力化を実現しつつ、且つ上記のような異常な温度変化を引き起こす外乱が生じた場合であっても、ある一定の温度範囲を維持することができる、冷媒圧縮機の制御装置及び制御方法を提供することにある。
【０００９】
【課題を解決するための手段】
上記の目的を達成するため、本発明者等は、冷媒圧縮機の目標温度調節制御に前述のオン／オフ制御を適用することにより、省電力化を実現しつつ、且つ前述のような温度異常を生じさせないための検討を行った結果、以下のような結論に至った。ここでは、室内の冷房運転の場合を例として説明する。
【００１０】
まず、目標温度調節制御と並列して、オン／オフ制御を組み込む。そして、目標温度とは別に、室温の上限温度を予め設定し、実測した室温がこの上限温度の範囲内であればオン／オフ制御を行い、上限温度を超えた場合にのみ目標温度調節制御を行う。さらに、一定時間経過後、再び実測した室温と上限温度とを比較し、目標温度調節による制御を継続するか、オン／オフ制御へ戻るかを判断する。こうすることにより、室温が継続的に上限温度を超えるような異常な状態を回避しつつ、オン／オフ制御による省電力効果を享受することができる。
【００１１】
また、前記の目標温度調節による制御中に実測温度と上限温度とを比較判定する時間間隔（判定周期）には、適正範囲が存在する。すなわち、この判定時間間隔が長すぎると、目標温度調節による制御時間が長すぎて、省電力効果が減少してしまう。一方、この判定周期が短すぎると、オン／オフ制御へ戻っても、すぐに上限温度を超えて再び目標温度調節による制御になるなど、目標温度調節による制御とオン／オフ制御との間で制御システムが振動動作を起こし、制御が安定しない。また、この判定時間間隔の適正値は、その時の外気温度や室内の熱応答性に配慮する必要があり、季節や時間帯等を考慮することが望ましい。
【００１２】
さらに、前述の上限温度の設定値に関しても、季節や時間帯等を考慮した方が望ましく、また空調対象の許容温度（温度調整を必要とする対象物の品質，性能が保持される温度）に対して多少の余裕を持って決定することが望ましい。
【００１３】
本発明の冷媒圧縮機の制御装置及び制御方法は、以上のような検討結果に基づきなされたもので、以下のような特徴を有する。
【００１４】
（１）空調対象の温度を実測し、冷媒圧縮機の駆動／停止を予め設定した目標温度となるように制御する目標温度調節制御手段を備えた冷媒圧縮機の制御装置において、前記空調対象の上限温度及び／又は下限温度を予め設定する上下限温度設定手段と、前記上限温度及び／又は下限温度と前記空調対象の温度実測値とを比較判定する第１の実測温度比較判定手段と、前記実測温度比較判定結果に基づき、前記温度実測値が、前記上限温度及び／又は下限温度の範囲内にある場合には前記圧縮機の駆動／停止を周期的に繰り返すオン／オフ制御モードとし、前記上限温度又は下限温度を超えている場合には前記目標温度調節制御モードとする、前記圧縮機の運転制御モード切替手段と、前記目標温度調節制御モードによる前記圧縮機の運転制御中に、予め設定した判定時間間隔で、前記上限温度及び／又は下限温度と前記空調対象の温度実測値とを比較判定する第２の実測温度比較判定手段とを備えたことを特徴とする冷媒圧縮機の制御装置。
【００１５】
（２）第２の実測温度比較判定手段が比較判定を行う判定時間間隔を、季節，月，曜日，時間帯のうちのいずれか１以上毎に定めた比較判定時間テーブルとして備えたことを特徴とする、上記（１）に記載の冷媒圧縮機の制御装置。
【００１６】
（３）比較判定時間テーブルの値が１２０秒以上の値であることを特徴とする、上記（２）に記載の冷媒圧縮機の制御装置。
【００１７】
（４）上下限温度設定手段が、上限温度及び／又は下限温度設定値を、季節，月，曜日，時間帯のうちのいずれか１以上毎に定めた上下限温度テーブルとして備えたことを特徴とする、上記（１）乃至（３）のいずれかに記載の冷媒圧縮機の制御装置。
【００１８】
（５）上下限温度テーブルの値が、空調対象の許容温度に対して、上限温度設定値は前記許容温度の上限値−１℃以下、下限温度設定値は前記許容温度の下限値＋１℃以上の値であることを特徴とする、上記（４）に記載の冷媒圧縮機の制御装置。
【００１９】
（６）複数台の圧縮機を備えた場合に、第１及び／又は第２の実測温度比較判定結果に基づいて、前記圧縮機のオン／オフ制御モードと目標温度調節制御モードとの運転制御モード切替を行う前記圧縮機の台数を決定する、運転台数制御手段を備えたことを特徴とする、上記（１）乃至（５）のいずれかに記載の冷媒圧縮機の制御装置。
【００２０】
（７）空調対象の温度を実測し、冷媒圧縮機の駆動／停止を予め設定した目標温度となるように制御する目標温度調節機能を備えた冷媒圧縮機の制御方法において、前記空調対象の上限温度及び／又は下限温度を予め設定し、前記上限温度及び／又は下限温度と前記空調対象の温度実測値とを比較判定し、前記温度実測値が前記上限温度及び／又は下限温度の範囲内にある場合には、圧縮機の駆動／停止を周期的に繰り返すオン／オフ制御モードとし、前記上限温度又は下限温度を超えている場合には、前記目標温度調節制御モードとするとともに、前記目標温度調節制御モードによる前記圧縮機の運転制御中にあっては、予め設定した判定時間間隔で、前記上限温度及び／又は下限温度と前記空調対象の温度実測値とを比較判定し、前記温度実測値が前記上限温度又は下限温度を超えている場合には引き続き目標温度調節制御モードを継続し、前記上限温度及び／又は下限温度の範囲内の場合にはオン／オフ制御モードへ切り替えることを特徴とする冷媒圧縮機の制御方法。
【００２１】
（８）目標温度調節制御モードによる運転制御中に実測温度比較判定を行う判定時間間隔を、季節，月，曜日，時間帯のうちのいずれか１以上毎に定めた比較判定時間テーブルにより決定することを特徴とする、上記（７）に記載の冷媒圧縮機の制御方法。
【００２２】
（９）上限温度及び／又は下限温度設定値を、季節，月，曜日，時間帯のうちのいずれか１以上毎に定めた上下限温度テーブルにより決定することを特徴とする、上記（７）又は（８）に記載の冷媒圧縮機の制御方法。
【００２３】
（１０）複数台の圧縮機を備えた場合に、実測温度比較判定結果に基づき、前記圧縮機のオン／オフ制御モードと目標温度調節制御モードとの運転制御モード切替を行う前記圧縮機の台数を制御すること特徴とする、上記（７）乃至（９）のいずれかに記載の冷媒圧縮機の制御方法。
【００２４】
【発明の実施の形態】
以下、本発明の実施の形態について説明する。
【００２５】
（第１の実施形態）
図１は、本発明の第１の実施形態に係る空調システムの一例を示す構成図である。
【００２６】
本図において、空調対象４とは、冷凍庫，冷蔵庫，オフィス等の室内など、冷凍，冷房，暖房のいずれかを必要とする空間である。そして、空調対象４の室内には、空調機２が設けられている。また、各空調機２に近接して、空調対象４の室内の温度を実測する温度センサー３が設けられている。そして、これらの各温度センサー３からの温度実測値を受け取り、空調機２へ運転指令を出す制御部１を備えている。
【００２７】
空調機２は、その内部に冷媒圧縮機、熱交換器、送風機等を備え、制御部１からの指令により、冷気や暖気を空調対象４内へ送風するものである。なお、図２は本発明の第１の実施形態に係る空調システムの他の一例を示す構成図であるが、本図に示すように、空調機２は、室内機２ａと室外機２ｂとに分かれていてもよい。この場合、室内機２ａ側に熱交換器、送風機等が、また室外機２ｂ側に熱交換器、冷媒圧縮機等が備えられる。また、空調機２を空調対象４の外部に設け、冷気や暖気を配管を通じて空調対象４内へ送風してもよい。
【００２８】
温度センサー３は、空調対象４内の温度を実測するものである。図１では、空調機２に近接して設けているが、空調機２へ内蔵してもよいし、空調機２の設置位置とは別の、室温を代表する適切な位置に設けてもよい。また、空調対象４内の複数箇所に設置してもよい。複数箇所に設置した場合、複数の温度実測値は、平均化処理されたり、最大値や最小値が用いられたりする。
【００２９】
制御部１は、温度センサー３から送られる空調対象４内の温度情報により、空調機２の運転（冷媒圧縮機の駆動／停止）を制御するものである。制御部１に備える特徴的な主な機能を実現する手段として、
▲１▼空調対象４の上限温度及び／又は下限温度を予め設定する上下限温度設定手段
▲２▼前記上下限温度と温度センサー３により実測された温度実測値とを比較判定する第１の実測温度比較判定手段
▲３▼前記実測温度比較判定結果に基づき、冷媒圧縮機の運転を、オン／オフ制御モードと目標温度調節制御モードとの間で切り替える冷媒圧縮機の運転制御モード切替手段
▲４▼前記目標温度調節制御モードによる圧縮機の運転制御中に、予め設定した判定時間間隔で、前記上下限温度と温度センサー３により実測された温度実測値とを比較判定する第２の実測温度比較判定手段
を備えている。
【００３０】
なお、▲１▼において、上下限温度設定手段は、上限温度と下限温度の両方を設定しても、片方のみを設定してもよい。以下の説明では、「上下限温度」を、「上限温度及び／又は下限温度」の意味で用いる。
【００３１】
また、上記▲４▼において用いる予め設定する判定時間間隔として、季節，月，曜日，時間帯等の一部又は全部、あるいは更なる条件を加えたもの毎に定めた、比較判定時間テーブルを設けることが望ましい。さらに、上記▲２▼において用いる予め設定する上下限温度設定値として、季節，月，曜日，時間帯等の一部又は全部、あるいは更なる条件を加えたもの毎に定めた、上下限温度設定テーブルを設けることが望ましい。その理由は、その時の外気温や空調対象４内の熱応答性によって、これらの適正値が異なるためである。例えば、外気温を考慮して季節毎や月毎にテーブルを設けたり、営業日や営業時間帯、人や物の出入りの激しい時間帯等を考慮して、曜日毎や時間帯毎にテーブルを設けることができる。以上のようにして定めるテーブルを設けることにより、温度異常の発生を防止し、且つ無駄な運転を抑制して省電力化を図ることができる。
【００３２】
表１に、上下限温度設定テーブルの一例として、月毎及び時間帯毎に設けたテーブルの一例を示す。これは、あるオフィスビルの空調に用いる上下限温度設定テーブルのうち、ある月の時間帯別上限温度テーブルの例である。このように、月毎に時間帯別の設定値を定めたテーブルを用意しておくことができる。
【００３３】
【表１】

【００３４】
ここで、比較判定時間テーブルの値は、１２０秒以上の値とすることが好ましい。前述したように、判定時間間隔は、その時々で好ましい値が異なるものである。しかし、いずれの場合であっても、１２０秒よりも短い間隔で比較判定を行うと、前記したような、オン／オフ制御モードと目標温度調節制御モードとの間で制御システムが振動動作を起こす危険性が高い。その結果、制御が安定しないばかりか、頻繁な起動／停止の繰り返しにより冷媒圧縮機に過大な負荷をかけることとなり、冷媒圧縮機やその電動機が壊れる場合もある。また、圧縮機の停止直後は冷媒が液状のまま熱交換器から戻るため、停止直後に圧縮機を再起動すると、液状冷媒が圧縮機に流入していわゆる液圧縮を起こし、圧縮機のシリンダ等を壊す恐れがある。したがって、このような液状冷媒をガス化させるための時間を確保する上からも、比較判定時間テーブルの値は、最低でも１２０秒以上の値とすることが好ましい。
【００３５】
一方、この判定時間間隔が長すぎる場合には、目標温度調節モードによる運転時間が長すぎて、省電力効果が減少してしまう。本発明者等の検討によれば、３〜２０分の範囲が、制御システムや空調対象温度が安定し、且つ省電力化を図ることができる、特に好ましい範囲である。
【００３６】
また、上下限温度テーブルの値は、空調対象の許容温度を考慮して、１℃以上の余裕を持って設定されることが好ましい。ここで、空調対象の許容温度とは、空調対象の室内に置かれる物品の品質や性能が保持される温度や、室内の人が許容できる温度などである。そして、冷媒圧縮機の運転を変更してからそれに伴う温度変化が生じるまでの時間遅れの影響や、空調対象内の温度ムラの影響を吸収するためには、１℃以上の余裕が必要である。つまり、上下限温度テーブルの値は、空調対象の許容温度に対して、上限温度設定値は許容温度の上限値−１℃以下、下限温度設定値は前記許容温度の下限値＋１℃以上とすることが好ましい。
【００３７】
次に、以上のように構成された本実施形態における空調システムの動作について説明する。
【００３８】
図１及び図２において、空調対象４内の温度は、温度センサー３により実測され、その温度実測値が制御部１へ送られる。制御部１では、送られた温度実測値に基づき、後述する空調機２の適切な運転を判断し、空調機２（図２の場合には室外機２ｂ）に対して、冷媒圧縮機の駆動／停止を指令する。そして、空調機２（図２の場合には室内機２ａ）により、空調対象４内へ適切な冷気又は暖気の送風がなされ、空調対象４内は適正温度に維持される。
【００３９】
ここで、本発明では、予め設定した目標温度となるように制御する目標温度調節制御と、空調対象４の温度にかかわらず圧縮機の駆動／停止を周期的に繰り返すオン／オフ制御とを併用して、冷媒圧縮機の運転制御が行われる。そして、その動作は、以下の通りである。
【００４０】
図３は、制御部１における実測温度判定手順の一例を示すブロック図であり、（ａ）は第１の実測温度比較判定手段を用いる手順、（ｂ）は第２の実測温度比較判定手段を用いる手順である。
【００４１】
まず、本図（ａ）に示す第１の実測温度比較判定手段を用いる手順において、温度センサー３により実測された温度実測値は、常時又は短時間周期で、実測温度判定部１１ａへ送られる。実測温度判定部１１ａでは、記憶部１４ａに保存された上下限温度テーブル１５よりその時の条件に合ったテーブルが選択され、上下限温度が設定される。そして、この上下限温度と前記温度実測値とが比較判定されて、その判定結果が圧縮機運転指令部１２ａへ送られる。圧縮機運転指令部１２ａでは、前記判定結果により、圧縮機の制御を、温度実測値が上下限温度の範囲内であればオン／オフ制御とし、上下限温度を超えている場合には目標温度調節制御へ切り替えるように、冷媒圧縮機の運転指令を出す。そして、これらの運転指令は冷媒圧縮機へ送られ、この運転指令に従って冷媒圧縮機が駆動／停止する。
【００４２】
次に、上記の第１の実測温度比較判定手段を用いた結果、冷媒圧縮機が目標温度調節制御モードによる運転となった場合には、図３（ｂ）に示す第２の実測温度判定手段を用いる手順へ進む。本図において、比較判定時間判定部１３では、記憶部１４ｂに保存された比較判定時間テーブル１６よりその時の条件に合ったテーブルが選択され、実測温度比較判定を行う判定時間間隔が設定される。そして、設定された判定時間間隔経過後、比較判定時間判定部１３へ送られた温度センサー３により実測された温度実測値が、実測温度判定部１１ｂへ送られる。実測温度判定部１１ｂでは、記憶部１４ａに保存された上下限温度テーブル１５よりその時の条件に合ったテーブルが選択され、上下限温度が設定される。そして、この上下限温度と前記温度実測値とが比較判定されて、その判定結果が圧縮機運転指令部１２ｂへ送られる。圧縮機運転指令部１２ｂでは、前記判定結果により、温度実測値が上下限温度の範囲内であればオン／オフ制御モードへ切り替え、以降は図３（ａ）の第１の実測温度判定手段を用いる手順に従う。一方、引き続き上下限温度を超えている場合には、前記の目標温度調節制御モードを継続し、再び図３（ｂ）の第２の実測温度判定手段を用いる手順に従って、所定の判定時間間隔経過後に再判定を行う。
【００４３】
以上の繰り返しにより、制御部１からの指令によって、空調機の冷媒圧縮機が制御され続ける。
【００４４】
上述したように、本実施形態の冷媒圧縮機の制御装置によれば、冷媒圧縮機の運転をオン／オフ制御により行う断続運転手段を備えているため、省電力化を図ることができる。また、第１の実測温度比較判定手段を用い、空調対象の温度が上下限値を超えないように監視し、超えた場合には直ちに目標温度調節制御モードへ切り替えることにより、温度異常の発生を防止することができる。また、第２の実測温度比較判定手段を用い、目標温度調節制御モードへ切り替え後、適切な時間経過後にオン／オフ制御への切り替えの可否を判断することにより、省電力化を図るとともに、安定した制御を実現することができる。
【００４５】
また、本実施形態の冷媒圧縮機の制御方法によれば、冷媒圧縮機の運転を通常はオン／オフ制御により制御しているため、省電力化を図ることができる。また、空調対象の温度が上下限値を超えないように監視し、超えた場合には直ちに目標温度調節制御モードへ切り替えるため、温度異常の発生を防止することができる。さらに、温度調節制御モードへ切り替え後、適切な時間経過後にオン／オフ制御へ切り替えるため、省電力化を図るとともに、安定した制御を実現することができる。
【００４６】
なお、以上の説明では、空調対象４内に、空調機２を１台設置した場合について述べてきたが、本発明はこれに限定されるものではない。すなわち、空調対象４内に、複数の空調機２を設置してもよい。また、空調機が室内機２ａと室外機２ｂである場合には、１台の室外機２ｂに複数の室内機２ａを連結してもよい。さらに、複数の空調機２が個別に温度センサー３を備えている場合等には、各空調機２毎に個別に本実施形態の制御を行ってもよいし、複数の温度センサーからの温度実測値の最大／最小値や平均値等により、複数の空調機２を同時に制御してもよい。例えば、図４に第１の実施形態に係る複数の空調機を備えた空調システムの一例を示す構成図を示すが、このような構成であっても、前記した本発明の効果を得ることができる。
【００４７】
（第２の実施形態）
図５は、本発明の第２の実施形態に係る空調システムの一例を示す構成図である。図１と同一部分には同一符号を付して説明を省略し、ここでは異なる部分についてのみ述べる。
【００４８】
本実施形態では、空調対象４の室内に複数の空調機２が設けられている。また、空調対象４の室内の代表温度を実測することができる位置に、温度センサー３が設けられている。なお、温度センサー３を室内の複数箇所に設け、各温度センサー３により実測された温度の平均値を求める等の処理を行ってもよい。
【００４９】
制御部２０は、第１の実施形態における制御部１とほぼ同じものであるが、以下の点が異なっている。すなわち、制御部２０に備える、制御部１とは異なる特徴的な主な機能を実現する手段として、
▲１▼空調対象４の上限温度及び／又は下限温度を、複数の段階（例えば、一次上限値，二次上限値等）に予め設定する上下限温度設定手段
▲２▼前記複数段階の上下限温度と温度センサー３により実測された温度実測値とを比較判定する第１の実測温度比較判定手段
▲３▼前記実測温度比較判定結果に基づき、冷媒圧縮機の運転を、オン／オフ制御モードと目標温度調節モードとの間で切り替える冷媒圧縮機の台数を決定する運転台数制御手段
▲４▼前記目標温度調節制御モードによる圧縮機の運転制御中に、予め設定した判定時間間隔で、前記複数段階の上下限温度と温度センサー３により実測された温度実測値とを比較判定する第２の実測温度比較判定手段
を備えている。
【００５０】
ここで、上記▲１▼において用いる予め設定する複数の段階の上下限温度設定値は、目標温度との温度差の程度、あるいは空調対象の許容温度との温度差の程度等により、予め設定する上下限温度を複数の段階に設定するものである。すなわち、第１の実施形態のように、温度実測値が上下限温度に達したら複数の空調機を一斉に目標温度調節制御モードへ切り替えるのではなく、実測温度に応じて段階的に前記運転の切り替えを行うためのものである。例えば、複数設置した空調機の半数の運転を切り替える一次上下限温度と、全部の運転を切り替える二次上下限温度を設定する。なお、これら複数段階に定める上下限温度設定値についても、季節，月，曜日，時間帯等の一部又は全部、あるいは更なる条件を加えたもの毎に定めた、上下限温度設定テーブルとして設けることが望ましい。このようにして定める複数段階のテーブルを設けることにより、第１の実施形態と比較して、温度異常の発生を未然に防止し、より狭い範囲に温度調節をすることができる。また、無駄な運転をより抑制して、省電力化を図ることができる。
【００５１】
次に、以上のように構成された本実施形態における空調システムの動作について説明する。
【００５２】
図５において、空調対象４内の温度は、温度センサー３により実測され、その温度実測値が制御部２０へ送られる。制御部２０では、送られた温度実測値に基づき、空調機２の適切な運転を判断し、複数の空調機２に対して、冷媒圧縮機の駆動／停止を個別あるいはいくつかのグループに分けて指令する。そして、空調機２により、空調対象４内へ適切な冷気又は暖気の送風がなされ、空調対象４内は適正温度に維持される。
【００５３】
図６は、制御部２０における実測温度判定手順の一例を示すブロック図であり、（ａ）は第１の実測温度比較判定手段を用いる手順、（ｂ）は第２の実測温度比較判定手段を用いる手順である。図３と同一部分には同一符号を付して説明を省略し、ここでは異なる部分についてのみ述べる。
【００５４】
まず、本図（ａ）に示す第１の実測温度比較判定手段を用いる手順において、温度センサー３により実測された温度実測値は、常時又は短時間周期で、実測温度判定部２１ａへ送られる。実測温度判定部２１ａでは、記憶部２４ａに保存された複数段階の上下限温度テーブル２５ａ，２５ｂより、その時の条件に合ったテーブルが選択され、複数段階の上下限温度が設定される。そして、この上下限温度と前記温度実測値とが比較判定されて、その判定結果が運転台数決定部２７へ送られる。運転台数決定部２７では、記憶部２４ｃに保存された運転台数テーブル２８より、その時の条件に合ったテーブルが選択され、圧縮機の運転を目標温度調節制御モードへ切り替える台数が決定される。そして、その結果が圧縮機運転指令部２２ａへ送られる。圧縮機運転指令部２２ａでは、前記結果により、決定された台数の冷媒圧縮機を目標温度調節制御モードへ切り替え、残りの台数はそのままオン／オフ制御を継続するように、冷媒圧縮機の運転指令を出す。そして、これらの運転指令は各冷媒圧縮機へ送られ、この運転指令に従って各冷媒圧縮機が駆動／停止する。
【００５５】
次に、上記の第１の実測温度比較判定手段を用いた結果、冷媒圧縮機が目標温度調節制御モードによる運転となった場合には、図６（ｂ）に示す第２の実測温度判定手段を用いる手順へ進む。本図の説明は、上記図６（ａ）の説明と図３（ｂ）の説明から明らかであるので省略する。
【００５６】
なお、第１の実測温度比較判定手段を用いた結果、オン／オフ制御モードを継続する圧縮機と、目標温度調節制御モードへ切り替える圧縮機とが混在する場合がある。そのような場合には、すべての圧縮機に対して第２の実測温度比較判定手段を用いる手順を適用してもよいし、目標温度調節制御モードでの運転となった圧縮機のみ第２の実測温度比較判定手段を用いる手順を適用してもよい。
【００５７】
以上の繰り返しにより、制御部２０からの指令によって、空調機の冷媒圧縮機が制御され続ける。
【００５８】
上述したように、本実施形態の冷媒圧縮機の制御装置によれば、空調対象の温度の上下限値を複数段階に設けて監視し、その温度に応じて目標温度調節制御モードへ切り替える圧縮機の台数を制御する手段を備えているため、第１の実施形態による効果に加えて、温度異常の発生を未然に防止し、より省電力化を図ることができる。
【００５９】
また、本実施形態の冷媒圧縮機の制御方法によれば、空調対象の温度を複数段階に設けた上下限値と比較し、適切な台数の圧縮機を目標温度調節制御モードへ切り替えるため、第１の実施形態による効果に加えて、温度異常の発生を未然に防止し、より省電力化を図ることができる。
【００６０】
なお、以上の第１及び第２の実施形態で用いる冷媒圧縮機に、短時間での再起動を制限する保護回路を有する場合がある。これは、前記したように、頻繁な起動／停止により過大な負荷がかかることを防止したり、停止直後の再起動により液圧縮が起こることを防止するための機能である。このような保護回路を有する場合、本発明による運転指令と矛盾することがあり得る。例えば、冷房運転において、オン／オフ制御による運転停止直後に空調対象が上限温度を超えて、目標温度調節制御により圧縮機に運転指令が出される場合などである。そのような場合には、冷媒圧縮機の保護回路を優先させ、前記保護回路が働かなくなった後に、本発明による運転指令に従って圧縮機の制御を行えばよい。
【００６１】
次に、さらに具体的な冷媒圧縮機の制御例として、図４に示す第１の実施形態に係る空調システムにより、室内の冷房運転を行う場合の一例を示す。
【００６２】
図７は、冷房運転時の空調対象の温度推移図の一例であり、（ａ）はオン／オフ制御のみの場合、（ｂ）は第１の実施形態に係る制御を行う場合である。なお、この空調対象内の熱負荷は、９時以降に増加を続け、１２時以降には低下に転じている。
【００６３】
図７（ａ）に示すオン／オフ制御の場合では、オン／オフのデューティー比は２０分運転／１０分停止とした。そして、この周期でオン／オフを繰り返す。
【００６４】
図７（ｂ）に示す第１の実施形態に係る制御の場合では、このときの上下限温度テーブルから得られる上限温度は２８℃とし、比較判定時間テーブルから得られる比較判定時間は１０分とした。また、オン／オフ制御時におけるデューティー比は２０分運転／１０分停止とした。そして、空調対象温度が上限温度２８℃以下であればオン／オフ制御モードとし、これを越えると１０分間は目標温度調節制御モードとして圧縮機の運転を行う。１０分後に上限温度以下となっていればオン／オフ制御モードへ戻る。その際に、オンとオフのどちらとなるかは、元のオン／オフ制御のサイクル（本図（ｂ）の点線）に従う。
【００６５】
図７に示すように、単純なオン／オフ制御（本図（ａ））では、熱負荷が増加すると、２８℃を超える時間が長く、３０℃近くまで達する場合もある。これに対し、第１の実施形態による制御では、熱負荷が増加した場合でも、上限温度２８℃を超えると目標温度調節制御モードとなるため、急激に空調対象温度は低下し、２８℃を超える時間はごく短時間である。また、一定時間経過後は再びオン／オフ制御へ戻るため、熱負荷が高い状態にあっても圧縮機が停止している時間があるので、省電力化も図ることができる。
【００６６】
【発明の効果】
以上説明したように、本発明によれば、冷凍機や空調機などにおける冷媒圧縮機を目標温度調節制御する際に、オン／オフ制御を併用することにより省電力化を実現でき、且つ異常な温度変化を引き起こす外乱が生じた場合であっても一定の温度範囲を維持することができる。
【図面の簡単な説明】
【図１】本発明の第１の実施形態に係る空調システムの一例を示す構成図。
【図２】本発明の第１の実施形態に係る空調システムの他の一例を示す構成図。
【図３】本発明の第１の実施形態に係る圧縮機の制御部における実測温度判定手順の一例を示すブロック図。
【図４】本発明の第１の実施形態に係る複数の空調機を備えた空調システムの一例を示す構成図。
【図５】本発明の第２の実施形態に係る空調システムの一例を示す構成図
【図６】本発明の第２の実施形態に係る圧縮機の制御部における実測温度判定手順の一例を示すブロック図。
【図７】冷房運転時の空調対象の温度推移図の一例であり、（ａ）はオン／オフ制御のみの場合、（ｂ）は第１の実施形態に係る制御を行う場合。
【符号の説明】
１　　制御部
２　　空調機
２ａ　空調機の室内機
２ｂ　空調機の室外機
３　　温度センサー
４　　空調対象
１１　　実測温度判定部
１２　　圧縮機運転指令部
１３　　比較判定時間判定部
１４　　記憶部
１５　　上下限値テーブル
１６　　比較判定時間テーブル
２０　　制御部
２１　　実測温度判定部
２２　　圧縮機運転指令部
２４　　記憶部
２５　　上下限値テーブル
２７　　運転台数決定部
２８　　運転台数テーブル[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a control device and a control method for a refrigerant compressor (compressor) incorporated in a refrigerator, an air conditioner, and the like.
[0002]
[Prior art]
The refrigerator and the air conditioner have a built-in refrigerant compressor. In a cooling operation by a refrigerator, a cooling operation and a heating operation by an air conditioner, the driving and stopping of the refrigerant compressor are controlled so that an air-conditioning target has a preset target temperature. Here, the air-conditioning target is a space that requires any of freezing, refrigeration, cooling, and heating, such as a freezer or a refrigerator, or a hall, an office, or a room in a general household. There is no limitation on the size.
[0003]
Such a method of controlling the compressor to reach a preset target temperature (hereinafter, referred to as target temperature adjustment control) is the most general method of controlling a compressor, and is currently widely used. However, since these compressors use a large amount of electric power, power saving is required, and various power saving studies have been made so far.
[0004]
One of such power saving methods is a method called on / off control. The on / off control is to perform an intermittent operation (intermittent operation) that periodically repeats driving / stopping the compressor irrespective of the target temperature or the actual temperature of the air conditioner. That is, after the compressor is driven for the predetermined time T1, the cycle of stopping the compressor for the predetermined time T2 and driving again is periodically repeated. For example, if the drive time T1 is 10 minutes and the stop time T2 is 5 minutes, the compressor is stopped for 1/3 of the time. Therefore, according to the on / off control, the driving of the compressor is forcibly stopped for a certain time regardless of the temperature of the air-conditioning target (such as room temperature), so that the driving time of the compressor is shortened, and power is saved. Can be achieved.
[0005]
[Problems to be solved by the invention]
However, this on / off control has the following problems.
[0006]
For example, in the case of a cooling operation using an indoor air conditioner, in the on / off control, the compressor is stopped for a certain time regardless of the room temperature, so that the room temperature rises above the target temperature while the compressor is stopped. There is. There is no problem if the temperature falls to the target temperature within the subsequent drive time of the compressor. However, if the temperature does not reach the target temperature, the compressor stops again and the room temperature further rises. As described above, in general, the temperature is slightly higher than the target temperature in the on / off control, but in some cases, the room temperature may abnormally rise.
[0007]
Such an abnormal increase in temperature occurs because the stop time of the compressor is too long as compared with the heat load to be cooled. Usually, a ratio of on / off time (duty ratio) is set so that such a problem does not occur. However, unusual abnormal situations (disturbances) occur, such as an abnormal rise in the outside air temperature, an abnormally large amount of people or objects in or out of the room, or an excessive amount of inventory, or a case where the indoor heating element generates abnormal heat. This may cause such a problem. As a result, the objects to be frozen, refrigerated, and cooled are damaged in quality and performance, and discomfort is given to people in the room.
[0008]
An object of the present invention is to realize power saving in target temperature adjustment control of a refrigerant compressor in a refrigerator, an air conditioner, or the like, and even when a disturbance that causes an abnormal temperature change as described above occurs. Another object of the present invention is to provide a control device and a control method for a refrigerant compressor that can maintain a certain temperature range.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, the present inventors apply the above-mentioned on / off control to the target temperature adjustment control of the refrigerant compressor, thereby realizing power saving and achieving the above temperature abnormality. As a result of the investigation for preventing the occurrence of the above, the following conclusion was reached. Here, a case of indoor cooling operation will be described as an example.
[0010]
First, an on / off control is incorporated in parallel with the target temperature adjustment control. Then, separately from the target temperature, an upper limit temperature of the room temperature is set in advance, and if the actually measured room temperature is within the range of the upper limit temperature, on / off control is performed, and the target temperature adjustment control is performed only when the room temperature exceeds the upper limit temperature. Do. Further, after a lapse of a predetermined time, the actually measured room temperature is compared with the upper limit temperature again to determine whether to continue the control by the target temperature adjustment or to return to the on / off control. By doing so, it is possible to enjoy the power saving effect of the on / off control while avoiding an abnormal state where the room temperature continuously exceeds the upper limit temperature.
[0011]
Also, there is an appropriate range for the time interval (judgment cycle) for comparing and judging the actually measured temperature and the upper limit temperature during the control by the target temperature adjustment. That is, if the determination time interval is too long, the control time for adjusting the target temperature is too long, and the power saving effect is reduced. On the other hand, if the determination cycle is too short, even if the control returns to the on / off control, the temperature immediately exceeds the upper limit temperature and is controlled again by the target temperature adjustment. The control system oscillates and the control is not stable. In addition, it is necessary to consider the outside air temperature and indoor thermal responsiveness at that time, and it is desirable to consider the season, time zone, and the like as the appropriate value of the determination time interval.
[0012]
Further, it is desirable that the set value of the above-mentioned upper limit temperature is also considered in consideration of the season, time zone, and the like, and the allowable temperature of the air-conditioning object (the temperature at which the quality and performance of the object requiring temperature adjustment is maintained). On the other hand, it is desirable to decide with some margin.
[0013]
A control device and a control method for a refrigerant compressor according to the present invention have been made based on the above study results and have the following features.
[0014]
(1) In a control device for a refrigerant compressor provided with target temperature adjustment control means for actually measuring the temperature of an object to be air-conditioned and controlling the driving / stopping of the refrigerant compressor to a preset target temperature, Upper and lower limit temperature setting means for presetting an upper limit temperature and / or a lower limit temperature, first actually measured temperature comparison and determination means for comparing the upper limit temperature and / or the lower limit temperature with the actually measured value of the air-conditioning object, When the measured temperature value is within the range of the upper limit temperature and / or the lower limit temperature based on the measured temperature comparison determination result, an on / off control mode for periodically repeating the drive / stop of the compressor is provided; An operation control mode switching means for the compressor, wherein the target temperature adjustment control mode is set when the temperature exceeds the upper limit temperature or the lower limit temperature, and an operation control of the compressor by the target temperature adjustment control mode. A second actually-measured temperature comparing and judging means for judging and comparing the upper-limit temperature and / or the lower-limit temperature with the actually measured value of the air-conditioning object at predetermined judgment time intervals. Control device for compressor.
[0015]
(2) The determination time interval at which the second actually measured temperature comparison determination means performs the comparison determination is provided as a comparison determination time table defined for at least one of season, month, day of the week, and time zone. The control device for a refrigerant compressor according to the above (1).
[0016]
(3) The control device for a refrigerant compressor according to (2), wherein the value of the comparison determination time table is a value of 120 seconds or more.
[0017]
(4) The upper and lower limit temperature setting means is provided with an upper and lower limit temperature table that sets the upper limit temperature and / or the lower limit temperature set value for at least one of season, month, day of week, and time zone. The control device for a refrigerant compressor according to any one of (1) to (3).
[0018]
(5) When the values in the upper and lower limit temperature table are relative to the allowable temperature of the air conditioner, the upper limit temperature set value is the upper limit of the allowable temperature -1 ° C or lower, and the lower limit temperature set value is the lower limit of the allowable temperature + 1 ° C or higher. The control device for a refrigerant compressor according to the above (4), wherein:
[0019]
(6) When a plurality of compressors are provided, the operation control of the on / off control mode and the target temperature adjustment control mode of the compressor based on the first and / or second actually measured temperature comparison determination results. The control device for a refrigerant compressor according to any one of (1) to (5), further including an operation number control unit that determines the number of the compressors that perform mode switching.
[0020]
(7) In a method of controlling a refrigerant compressor having a target temperature control function of actually measuring the temperature of an air-conditioning target and controlling the driving / stopping of the refrigerant compressor to a preset target temperature, the upper limit of the air-conditioning target The temperature and / or the lower limit temperature are set in advance, and the upper limit temperature and / or the lower limit temperature are compared with the measured temperature value of the object to be air-conditioned, and the measured temperature value is within the range of the upper limit temperature and / or the lower limit temperature. In some cases, an on / off control mode in which the driving / stop of the compressor is periodically repeated is set. When the temperature exceeds the upper limit temperature or the lower limit temperature, the target temperature adjustment control mode is set. During the operation control of the compressor in the adjustment control mode, the upper limit temperature and / or the lower limit temperature are compared and determined with the temperature measured value of the air-conditioning object at predetermined determination time intervals, and the temperature is determined. When the measured value exceeds the upper limit temperature or the lower limit temperature, the target temperature adjustment control mode is continued, and when the measured value is within the range of the upper limit temperature and / or the lower limit temperature, switching to the on / off control mode is performed. A method for controlling a refrigerant compressor.
[0021]
(8) The determination time interval for performing the measured temperature comparison determination during the operation control in the target temperature adjustment control mode is determined by a comparison determination time table defined for at least one of season, month, day of the week, and time zone. The method for controlling a refrigerant compressor according to the above (7), wherein:
[0022]
(9) The upper limit and / or lower limit temperature set values are determined by an upper and lower limit temperature table defined for at least one of season, month, day of the week, and time zone. Or the control method of the refrigerant compressor as described in (8).
[0023]
(10) In the case where a plurality of compressors are provided, the number of the compressors for performing the operation control mode switching between the on / off control mode of the compressor and the target temperature adjustment control mode based on the result of the measured temperature comparison and determination. The method for controlling a refrigerant compressor according to any one of the above (7) to (9), wherein
[0024]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described.
[0025]
(1st Embodiment)
FIG. 1 is a configuration diagram illustrating an example of an air conditioning system according to the first embodiment of the present invention.
[0026]
In this figure, an air-conditioning target 4 is a space that requires any of freezing, cooling, and heating, such as a freezer, a refrigerator, and an office room. The air conditioner 2 is provided in the room of the air conditioner 4. In addition, a temperature sensor 3 that measures the temperature of the room of the air-conditioned object 4 is provided near each air conditioner 2. The air conditioner 2 includes a control unit 1 that receives actual measured values from the temperature sensors 3 and issues an operation command to the air conditioner 2.
[0027]
The air conditioner 2 includes a refrigerant compressor, a heat exchanger, a blower, and the like therein, and blows cool air or warm air into the air-conditioning object 4 according to a command from the control unit 1. FIG. 2 is a configuration diagram illustrating another example of the air conditioning system according to the first embodiment of the present invention. As illustrated in FIG. 2, the air conditioner 2 includes an indoor unit 2a and an outdoor unit 2b. It may be divided. In this case, a heat exchanger, a blower, and the like are provided on the indoor unit 2a side, and a heat exchanger, a refrigerant compressor, and the like are provided on the outdoor unit 2b side. Further, the air conditioner 2 may be provided outside the object 4 to be cooled, and cool air or warm air may be blown into the object 4 through a pipe.
[0028]
The temperature sensor 3 measures the temperature inside the air conditioning object 4. In FIG. 1, the air conditioner 2 is provided near the air conditioner 2. However, the air conditioner 2 may be provided in the air conditioner 2, or may be provided at an appropriate position representing the room temperature, different from the installation position of the air conditioner 2. . Moreover, you may install in several places in the air-conditioning object 4. When installed at a plurality of locations, the plurality of measured temperature values are averaged or the maximum value or the minimum value is used.
[0029]
The control unit 1 controls the operation of the air conditioner 2 (drive / stop of the refrigerant compressor) based on the temperature information in the air conditioner 4 sent from the temperature sensor 3. As means for realizing the characteristic main functions provided in the control unit 1,
{Circle around (1)} Upper / lower limit temperature setting means for presetting the upper limit temperature and / or the lower limit temperature of the air-conditioning object 4 [2] First actual measurement for comparing the upper / lower limit temperature with the actual temperature measured by the temperature sensor 3 Temperature comparison / judgment means (3) Operation control mode switching means (4) of the refrigerant compressor for switching the operation of the refrigerant compressor between an on / off control mode and a target temperature adjustment control mode based on the actual measured temperature comparison / judgment result. ▼ During the operation control of the compressor in the target temperature adjustment control mode, a second actually measured temperature comparison for judging and comparing the upper and lower limit temperatures and the actually measured temperature value measured by the temperature sensor 3 at predetermined judgment time intervals. A determination means is provided.
[0030]
In (1), the upper and lower limit temperature setting means may set both the upper limit temperature and the lower limit temperature, or may set only one of them. In the following description, “upper / lower limit temperature” is used to mean “upper limit temperature and / or lower limit temperature”.
[0031]
In addition, as the preset determination time interval used in the above (4), a comparison determination time table is provided which is set for a part or all of the season, month, day of the week, time zone, or the like, or for each additional condition. It is desirable. Further, as upper and lower limit temperature set values used in the above (2), upper and lower limit temperature setting values set for some or all of seasons, months, days of the week, time zones, and the like, or for each additional condition are added. It is desirable to provide a table. The reason is that these appropriate values differ depending on the outside air temperature at that time and the thermal responsiveness of the air-conditioning object 4. For example, a table may be provided for each season or month in consideration of the outside temperature, or a table for each day of the week or time zone, taking into account business days and business hours, times when people and goods enter and exit intensely, etc. Can be provided. By providing the table determined as described above, it is possible to prevent the occurrence of temperature abnormality, suppress unnecessary operation, and save power.
[0032]
Table 1 shows an example of a table provided for each month and time zone as an example of an upper and lower limit temperature setting table. This is an example of a time zone upper limit temperature table for a certain month in the upper and lower limit temperature setting tables used for air conditioning of an office building. In this way, it is possible to prepare a table in which the set value for each time zone is determined for each month.
[0033]
[Table 1]

[0034]
Here, the value of the comparison determination time table is preferably set to a value of 120 seconds or more. As described above, the judgment time interval has a different preferable value at each time. However, in any case, if the comparison determination is made at intervals shorter than 120 seconds, the control system will vibrate between the on / off control mode and the target temperature adjustment control mode as described above. High risk. As a result, not only is the control unstable, but frequent repetition of starting / stopping causes an excessive load to be applied to the refrigerant compressor, and the refrigerant compressor and its electric motor may be broken. Also, immediately after the compressor stops, the refrigerant returns from the heat exchanger in a liquid state. Therefore, when the compressor is restarted immediately after the stop, the liquid refrigerant flows into the compressor, causing so-called liquid compression, and the cylinder of the compressor, etc. May be destroyed. Therefore, from the viewpoint of securing time for gasifying the liquid refrigerant, the value of the comparison determination time table is preferably set to a value of at least 120 seconds or more.
[0035]
On the other hand, if the determination time interval is too long, the operation time in the target temperature adjustment mode is too long, and the power saving effect is reduced. According to the study by the present inventors, a range of 3 to 20 minutes is a particularly preferable range in which the control system and the air conditioning target temperature can be stabilized and power saving can be achieved.
[0036]
Further, it is preferable that the values in the upper and lower limit temperature table are set with a margin of 1 ° C. or more in consideration of the allowable temperature of the object to be air-conditioned. Here, the permissible temperature of the object to be air-conditioned is a temperature at which the quality and performance of articles placed in the room to be air-conditioned are maintained, and a temperature that can be tolerated by persons in the room. A margin of 1 ° C. or more is required to absorb the influence of the time delay from the change in the operation of the refrigerant compressor to the occurrence of a temperature change accompanying the change and the influence of the temperature unevenness in the air conditioner. . In other words, the values of the upper and lower limit temperature tables are set such that the upper limit temperature set value is equal to or lower than the upper limit value of the allowable temperature -1 ° C. and the lower limit temperature set value is equal to or higher than the lower limit value of the allowable temperature + 1 ° C. Is preferred.
[0037]
Next, the operation of the air conditioning system according to the present embodiment configured as described above will be described.
[0038]
1 and 2, the temperature inside the air conditioning target 4 is actually measured by the temperature sensor 3, and the measured temperature value is sent to the control unit 1. The control unit 1 determines an appropriate operation of the air conditioner 2 described later based on the sent measured temperature value, and controls the air conditioner 2 (the outdoor unit 2b in FIG. 2) to drive the refrigerant compressor. / Stop command. Then, the air conditioner 2 (in the case of FIG. 2, the indoor unit 2a) blows appropriate cool air or warm air into the air conditioner 4, and the air conditioner 4 is maintained at an appropriate temperature.
[0039]
Here, in the present invention, the target temperature adjustment control for controlling the temperature to be a preset target temperature and the on / off control for periodically repeating the drive / stop of the compressor regardless of the temperature of the air-conditioning target 4 are used in combination. Then, the operation control of the refrigerant compressor is performed. The operation is as follows.
[0040]
FIGS. 3A and 3B are block diagrams showing an example of the actually measured temperature determination procedure in the control unit 1. FIG. 3A is a procedure using the first actually measured temperature comparison and determination means, and FIG. 3B is a block diagram showing the second actually measured temperature comparison and determination means. This is the procedure used.
[0041]
First, in the procedure using the first actually measured temperature comparing and judging means shown in FIG. 9A, the actually measured temperature value measured by the temperature sensor 3 is sent to the actually measured temperature judging unit 11a constantly or in a short period. In the measured temperature determination unit 11a, a table that meets the condition at that time is selected from the upper and lower limit temperature table 15 stored in the storage unit 14a, and the upper and lower limit temperatures are set. Then, the upper and lower limit temperatures are compared and determined with the measured temperature value, and the determination result is sent to the compressor operation command section 12a. In the compressor operation command section 12a, based on the above determination result, the control of the compressor is set to on / off control if the measured temperature value is within the range of the upper and lower limits, and if the temperature exceeds the upper and lower limits, the target temperature is controlled. An operation command for the refrigerant compressor is issued so as to switch to the regulation control. These operation commands are sent to the refrigerant compressor, and the refrigerant compressor is driven / stopped according to the operation commands.
[0042]
Next, as a result of using the first actually measured temperature comparing and judging means, when the refrigerant compressor is operated in the target temperature adjustment control mode, the second actually measured temperature judging means shown in FIG. Proceed to the procedure using. In the figure, the comparison determination time determination unit 13 selects a table that meets the conditions at that time from the comparison determination time table 16 stored in the storage unit 14b, and sets a determination time interval for performing the actual measurement temperature comparison determination. Then, after a lapse of the set determination time interval, the measured temperature value actually measured by the temperature sensor 3 sent to the comparison determination time determination unit 13 is sent to the actually measured temperature determination unit 11b. In the measured temperature determination unit 11b, a table that meets the condition at that time is selected from the upper and lower limit temperature table 15 stored in the storage unit 14a, and the upper and lower limit temperatures are set. Then, the upper and lower limit temperatures are compared with the measured temperature value, and the result of the comparison is sent to the compressor operation command section 12b. The compressor operation command unit 12b switches to the on / off control mode if the measured temperature value is within the range of the upper and lower limit temperatures, based on the determination result, and thereafter sets the first measured temperature determination unit of FIG. Follow the procedure used. On the other hand, when the temperature exceeds the upper and lower limit temperatures, the target temperature adjustment control mode is continued, and a predetermined determination time interval elapses again according to the procedure using the second actually measured temperature determination means in FIG. Re-determination will be performed later.
[0043]
By the above repetition, the refrigerant compressor of the air conditioner is continuously controlled by the command from the control unit 1.
[0044]
As described above, according to the refrigerant compressor control device of the present embodiment, since the intermittent operation means for operating the refrigerant compressor by on / off control is provided, power saving can be achieved. Also, using the first actually measured temperature comparison / judgment means, the temperature of the air-conditioning object is monitored so as not to exceed the upper and lower limits, and if it exceeds, the mode is immediately switched to the target temperature adjustment control mode, so that the occurrence of temperature abnormality can be prevented. Can be prevented. Further, by switching to the on / off control after an appropriate time has elapsed after switching to the target temperature adjustment control mode using the second actually measured temperature comparing and determining means, power saving is achieved and stable operation is achieved. Control can be realized.
[0045]
Further, according to the refrigerant compressor control method of the present embodiment, the operation of the refrigerant compressor is normally controlled by on / off control, so that power saving can be achieved. In addition, since the temperature of the air-conditioning target is monitored so as not to exceed the upper and lower limit values, and if it exceeds, the mode is immediately switched to the target temperature adjustment control mode, so that occurrence of a temperature abnormality can be prevented. Further, after switching to the temperature adjustment control mode, switching to on / off control is performed after an appropriate time elapses, so that power can be saved and stable control can be realized.
[0046]
In the above description, the case where one air conditioner 2 is installed in the air conditioner 4 has been described, but the present invention is not limited to this. That is, a plurality of air conditioners 2 may be installed in the air conditioner 4. When the air conditioners are the indoor unit 2a and the outdoor unit 2b, a plurality of indoor units 2a may be connected to one outdoor unit 2b. Further, when the plurality of air conditioners 2 are individually provided with the temperature sensors 3 or the like, the control of the present embodiment may be individually performed for each of the air conditioners 2 or the temperature measurement from the plurality of temperature sensors may be performed. A plurality of air conditioners 2 may be controlled simultaneously based on the maximum / minimum value or average value. For example, FIG. 4 shows a configuration diagram illustrating an example of an air conditioning system including a plurality of air conditioners according to the first embodiment. Even with such a configuration, the effects of the present invention described above can be obtained. it can.
[0047]
(Second embodiment)
FIG. 5 is a configuration diagram illustrating an example of an air conditioning system according to the second embodiment of the present invention. The same parts as those in FIG. 1 are denoted by the same reference numerals, and description thereof will be omitted. Only different parts will be described here.
[0048]
In the present embodiment, a plurality of air conditioners 2 are provided in the room of the air conditioner 4. The temperature sensor 3 is provided at a position where the representative temperature in the room of the air-conditioned object 4 can be actually measured. Note that the temperature sensors 3 may be provided at a plurality of places in the room, and processing such as obtaining an average value of the temperatures actually measured by the temperature sensors 3 may be performed.
[0049]
The control unit 20 is substantially the same as the control unit 1 in the first embodiment, but differs in the following points. That is, as means for realizing characteristic main functions different from the control unit 1 provided in the control unit 20,
{Circle around (1)} Upper and lower limit temperature setting means for presetting the upper limit temperature and / or lower limit temperature of the air-conditioning target 4 to a plurality of stages (for example, primary upper limit value, secondary upper limit value, etc.). A first actually measured temperature comparison / determination means for comparing and judging the temperature with an actually measured temperature actually measured by the temperature sensor 3; based on the actually measured temperature comparison / judgment result, the operation of the refrigerant compressor is switched to an on / off control mode. Operating number control means for determining the number of refrigerant compressors to be switched to and from the target temperature adjustment mode. {Circle around (4)} During the operation control of the compressor in the target temperature adjustment control mode, the plurality of steps are performed at predetermined judgment time intervals. And a second actually measured temperature comparing and judging means for judging and comparing the upper and lower limit temperatures with the actually measured temperature value measured by the temperature sensor 3.
[0050]
Here, the preset upper and lower limit temperature set values used in the above (1) are set in advance according to the degree of the temperature difference from the target temperature or the degree of the temperature difference from the allowable temperature of the air-conditioning object. The upper and lower limit temperatures are set in a plurality of stages. That is, as in the first embodiment, when the measured temperature reaches the upper and lower limit temperatures, the plurality of air conditioners are not simultaneously switched to the target temperature control mode, but the operation of the operation is performed stepwise according to the measured temperature. This is for switching. For example, a primary upper / lower limit temperature for switching half the operation of a plurality of installed air conditioners and a secondary upper / lower limit temperature for switching all the operations are set. Note that the upper and lower limit temperature set values determined in the plurality of stages are also provided as upper and lower limit temperature setting tables that are set for some or all of seasons, months, days of the week, time zones, and the like, or for each of the additional conditions. It is desirable. By providing a table of a plurality of stages determined in this way, it is possible to prevent the occurrence of abnormal temperature and control the temperature in a narrower range than in the first embodiment. Further, wasteful operation can be further suppressed, and power can be saved.
[0051]
Next, the operation of the air conditioning system according to the present embodiment configured as described above will be described.
[0052]
In FIG. 5, the temperature in the air-conditioning target 4 is actually measured by the temperature sensor 3, and the measured temperature value is sent to the control unit 20. The control unit 20 determines an appropriate operation of the air conditioner 2 based on the sent measured temperature value, and divides the drive / stop of the refrigerant compressor into a plurality of air conditioners 2 individually or in several groups. Command. Then, the air conditioner 2 blows appropriate cool air or warm air into the air conditioner 4, and the inside of the air conditioner 4 is maintained at an appropriate temperature.
[0053]
FIGS. 6A and 6B are block diagrams illustrating an example of a measured temperature determination procedure in the control unit 20. FIG. 6A illustrates a procedure using the first measured temperature comparison and determination means, and FIG. 6B illustrates a procedure using the second measured temperature comparison and determination means. This is the procedure used. The same parts as those in FIG. 3 are denoted by the same reference numerals, and description thereof will be omitted. Only different parts will be described here.
[0054]
First, in the procedure using the first actually measured temperature comparing and judging means shown in FIG. 9A, the actually measured temperature value actually measured by the temperature sensor 3 is sent to the actually measured temperature judging unit 21a constantly or in a short time cycle. In the measured temperature determination unit 21a, a table that matches the condition at that time is selected from the upper and lower limit temperature tables 25a and 25b stored in the storage unit 24a, and the upper and lower limit temperatures are set in multiple stages. Then, the upper and lower limit temperatures are compared and determined with the measured temperature value, and the determination result is sent to the operating number determining unit 27. The operating number determination unit 27 selects a table that meets the conditions at that time from the operating number table 28 stored in the storage unit 24c, and determines the number of units that switch the operation of the compressor to the target temperature control mode. Then, the result is sent to the compressor operation command section 22a. The compressor operation command unit 22a switches the determined number of refrigerant compressors to the target temperature control mode based on the result, and continues the on / off control of the remaining number of refrigerant compressors. Put out. These operation commands are sent to the respective refrigerant compressors, and the respective refrigerant compressors are driven / stopped according to the operation commands.
[0055]
Next, as a result of using the first actually measured temperature comparing and judging means, when the refrigerant compressor is operated in the target temperature adjustment control mode, the second actually measured temperature judging means shown in FIG. Proceed to the procedure using. The description of this drawing will be omitted because it is clear from the description of FIG. 6A and the description of FIG.
[0056]
As a result of using the first actually measured temperature comparison and determination means, there are cases where a compressor that continues the on / off control mode and a compressor that switches to the target temperature adjustment control mode are mixed. In such a case, the procedure using the second actually measured temperature comparison / determination means may be applied to all the compressors, or only the compressors that have been operated in the target temperature adjustment control mode may be used. A procedure using the actually measured temperature comparison determination means may be applied.
[0057]
By the repetition of the above, the refrigerant compressor of the air conditioner is continuously controlled by the command from the control unit 20.
[0058]
As described above, according to the refrigerant compressor control device of the present embodiment, the upper and lower limits of the temperature of the air conditioner are provided and monitored in a plurality of stages, and the compressor is switched to the target temperature adjustment control mode according to the temperature. In addition to the effects of the first embodiment, it is possible to prevent the occurrence of a temperature abnormality and further reduce the power consumption in addition to the effects of the first embodiment.
[0059]
According to the refrigerant compressor control method of the present embodiment, the temperature of the air-conditioning target is compared with upper and lower limit values provided in a plurality of stages, and an appropriate number of compressors are switched to the target temperature adjustment control mode. In addition to the effects of the first embodiment, it is possible to prevent a temperature abnormality from occurring and to achieve further power saving.
[0060]
It should be noted that the refrigerant compressor used in the first and second embodiments may have a protection circuit that limits restarting in a short time. As described above, this is a function for preventing an excessive load from being applied due to frequent start / stop, and preventing liquid compression from occurring due to restart immediately after stop. When such a protection circuit is provided, it may be inconsistent with the operation command according to the present invention. For example, in the cooling operation, a case where the air condition target exceeds the upper limit temperature immediately after the operation is stopped by the on / off control and an operation command is issued to the compressor by the target temperature adjustment control. In such a case, the protection circuit of the refrigerant compressor may be prioritized, and after the protection circuit stops working, the compressor may be controlled according to the operation command according to the present invention.
[0061]
Next, as a more specific example of the control of the refrigerant compressor, an example in which the air conditioning system according to the first embodiment shown in FIG. 4 performs the indoor cooling operation will be described.
[0062]
FIG. 7 is an example of a temperature transition diagram of an air-conditioning target during a cooling operation. FIG. 7A illustrates a case where only on / off control is performed, and FIG. 7B illustrates a case where control according to the first embodiment is performed. In addition, the heat load in this air-conditioning object continues to increase after 9 o'clock and starts to decrease after 12 o'clock.
[0063]
In the case of the on / off control shown in FIG. 7A, the on / off duty ratio was set to 20 minutes operation / 10 minutes stop. Then, on / off is repeated in this cycle.
[0064]
In the case of the control according to the first embodiment shown in FIG. 7B, the upper limit temperature obtained from the upper and lower limit temperature table at this time is 28 ° C., and the comparison determination time obtained from the comparison determination time table is 10 minutes. did. The duty ratio during the on / off control was 20 minutes operation / 10 minutes stop. If the temperature of the air-conditioning object is equal to or lower than the upper limit temperature of 28 ° C., the on / off control mode is set. If the temperature is lower than the upper limit temperature after 10 minutes, the operation returns to the on / off control mode. At this time, whether to be turned on or off follows the original cycle of the on / off control (the dotted line in this figure (b)).
[0065]
As shown in FIG. 7, in the simple on / off control ((a) in this figure), when the heat load increases, the time exceeding 28 ° C. is long, and the temperature may reach nearly 30 ° C. in some cases. On the other hand, in the control according to the first embodiment, even when the heat load increases, the target temperature adjustment control mode is set when the temperature exceeds the upper limit temperature of 28 ° C., so that the temperature of the air-conditioning object rapidly decreases and exceeds 28 ° C. The time is very short. Further, after a certain time has elapsed, the control returns to the on / off control again. Therefore, even when the heat load is high, there is a time when the compressor is stopped, so that power can be saved.
[0066]
【The invention's effect】
As described above, according to the present invention, when controlling the target temperature of a refrigerant compressor in a refrigerator, an air conditioner, or the like, power saving can be realized by using on / off control together, and abnormal abnormalities can be realized. It is possible to maintain a certain temperature range even when a disturbance causing a temperature change occurs.
[Brief description of the drawings]
FIG. 1 is a configuration diagram showing an example of an air conditioning system according to a first embodiment of the present invention.
FIG. 2 is a configuration diagram showing another example of the air conditioning system according to the first embodiment of the present invention.
FIG. 3 is a block diagram showing an example of a measured temperature determination procedure in a control unit of the compressor according to the first embodiment of the present invention.
FIG. 4 is a configuration diagram illustrating an example of an air conditioning system including a plurality of air conditioners according to the first embodiment of the present invention.
FIG. 5 is a configuration diagram showing an example of an air conditioning system according to a second embodiment of the present invention. FIG. 6 is an example of an actually measured temperature determination procedure in a control unit of a compressor according to a second embodiment of the present invention. Block Diagram.
FIG. 7 is an example of a temperature transition diagram of an air-conditioning target during a cooling operation, in which (a) shows a case where only on / off control is performed, and (b) shows a case where control according to the first embodiment is performed.
[Explanation of symbols]
REFERENCE SIGNS LIST 1 control unit 2 air conditioner 2a air conditioner indoor unit 2b air conditioner outdoor unit 3 temperature sensor 4 air conditioner 11 measured temperature determination unit 12 compressor operation command unit 13 comparison determination time determination unit 14 storage unit 15 upper and lower limit value table 16 Comparison determination time table 20 Control unit 21 Actual temperature determination unit 22 Compressor operation command unit 24 Storage unit 25 Upper / lower limit value table 27 Number of operating units determination unit 28 Number of operating units table

Claims

A controller for a refrigerant compressor including target temperature adjustment control means for actually measuring the temperature of an object to be air-conditioned and controlling drive / stop of the refrigerant compressor to a preset target temperature,
Upper and lower limit temperature setting means for presetting an upper limit temperature and / or a lower limit temperature of the air conditioning target,
First measured temperature comparison and determination means for comparing and determining the upper limit temperature and / or the lower limit temperature with the measured temperature value of the air-conditioning target;
Based on the measured temperature comparison determination result, when the measured temperature value is within the range of the upper limit temperature and / or the lower limit temperature, an on / off control mode that periodically repeats driving / stopping the compressor, When the temperature exceeds the upper limit temperature or the lower limit temperature, the target temperature adjustment control mode, the operation control mode switching means of the compressor,
A second actually measured temperature for comparing and determining the upper limit temperature and / or the lower limit temperature with the actually measured value of the air-conditioning target at predetermined time intervals during operation control of the compressor in the target temperature adjustment control mode; A control device for a refrigerant compressor, comprising: comparison determination means.

A determination time interval at which the second actually measured temperature comparison determination means performs the comparison determination is provided as a comparison determination time table defined for at least one of a season, a month, a day of the week, and a time zone; The control device for a refrigerant compressor according to claim 1.

The control device for a refrigerant compressor according to claim 2, wherein the value of the comparison determination time table is a value of 120 seconds or more.

The upper and lower limit temperature setting means is provided with an upper and lower limit temperature table which sets the upper limit temperature and / or the lower limit temperature set value for at least one of a season, a month, a day of the week, and a time zone. A control device for a refrigerant compressor according to any one of claims 1 to 3.

The values of the upper and lower limit temperature tables are, for the allowable temperature of the air conditioner, the upper limit temperature set value is the upper limit value of the allowable temperature -1 ° C or less, and the lower limit temperature set value is the lower limit value of the allowable temperature + 1 ° C or more. The control device for a refrigerant compressor according to claim 4, wherein the control device is provided.

When a plurality of compressors are provided, the operation control mode switching between the on / off control mode of the compressor and the target temperature adjustment control mode is performed based on the first and / or second actually measured temperature comparison determination results. The control device for a refrigerant compressor according to any one of claims 1 to 5, further comprising an operation number control unit that determines the number of the compressors to be performed.

In a control method of a refrigerant compressor having a target temperature adjustment function of actually measuring a temperature of an air-conditioning target and controlling drive / stop of the refrigerant compressor to a preset target temperature,
Setting an upper limit temperature and / or a lower limit temperature of the air conditioning object in advance;
The upper limit temperature and / or the lower limit temperature is compared with the measured temperature value of the object to be air-conditioned, and when the measured temperature value is within the range of the upper limit temperature and / or the lower limit temperature, driving / stopping of the compressor is performed. Is periodically turned on / off control mode, and when the temperature exceeds the upper limit temperature or the lower limit temperature, the target temperature adjustment control mode is set,
During the operation control of the compressor in the target temperature adjustment control mode, at a predetermined determination time interval, compare and determine the upper limit temperature and / or lower limit temperature and the actual measured value of the air conditioning target,
When the measured temperature value exceeds the upper limit temperature or the lower limit temperature, the target temperature adjustment control mode is continued. A method for controlling a refrigerant compressor, comprising:

The determination time interval for performing the measured temperature comparison determination during the operation control in the target temperature adjustment control mode is determined by a comparison determination time table defined for at least one of season, month, day of week, and time zone. The control method for a refrigerant compressor according to claim 7, wherein

9. The upper limit temperature and / or lower limit temperature set value is determined by an upper limit temperature table defined for each one or more of season, month, day of week, and time zone. 3. The method for controlling a refrigerant compressor according to item 1.

When a plurality of compressors are provided, the number of the compressors for performing the operation control mode switching between the on / off control mode of the compressor and the target temperature adjustment control mode is controlled based on the result of the measured temperature comparison determination. The control method for a refrigerant compressor according to any one of claims 7 to 9, wherein: