JPS6110978A - Parallel starting and operating method of motor driven compressor group operated in parallel - Google Patents

Abstract

PURPOSE:To enable to smoothly start and operate a plurality of motor driven compressors to be operated in parallel without particularly increasing the power source capacity by temporarily stopping the operating compressors, and simultaneously starting with low frequency the compressors by an inverter. CONSTITUTION:When an air conditioning load is small and only the first motor driven compressor is operated, an inverter IV is set to a low frequency voltage, a switch S1 is closed to start with low frequency a motor M1. As the load increases, when the second motor driven compressor is started in parallel, the switch S1 is first opened to temporarily stop the operating motor M1, the inverter frequency is decreased, the pressure balance time T of the compressor CP1 is waited to close the switches S1, S2, and the motors M1, M2 are simultaneously started with low frequency. Thus, smooth parallel starting and operating can be performed.

Description

【発明の詳細な説明】 〔発明の属する技術分野） 本発明は１台のインバータによって並列運転れる電動圧
縮機群の並列投入運転方法に関するものである。DETAILED DESCRIPTION OF THE INVENTION [Technical field to which the invention pertains] The present invention relates to a method for parallel operation of electric compressors that are operated in parallel by one inverter.

〔発明の技ｉ（コ的背狽とぞの問題ｊ久ロアｊどえ（４
【り１１中に塔載される空気調和１穴川電Ｑ）ノＩ−＋
析１１幾においＣは、複数台の電動Ｌ［縮（；（を共通
１．二］（Ｑｌ）た１台のｒンバータ（連中７１　’Ｊ
Ｊる回路／ｊ　Ｉ’＜とりることかある。第２図はその
Ｊ、う４丁回路り式をトイ１示したしの（・あっ（、交
流電動機Ｍ１ど珪焔機ＣＰ　１に３１、っ（第１の電動
圧縮機が（１１１成さね、交流電動機Ｍ　２と１Ｆ縮椴
ＣＰ２に」、）（互）２の電り３月−縮機かｉ、＋７．
成され、同様に交流電動（λＭ　３と＋７：　３！’（
１；火Ｃｌ）　３１．二、１．っ（第３の“電動）１−
牟１１１１戊か（＋４成され（いる。各交流電動機Ｍ１
．Ｍ２．Ｍ３はイれそれ開閉器Ｓ１．Ｓ２，８３を介し
・（共通のインバータＩＶに接続される。[Techniques of invention
[Air conditioning 1 Anagawa Den Q) No I-+ installed in R11
In analysis 11, C is one r inverter (common 1.2) (Ql) of multiple electric
Jru circuit/j I'< There is something to be done. Figure 2 shows Toy 1's J, 4-way circuit type. Yes, to the AC motor M2 and the 1F compressor CP2, ) (mutual) 2 electricity March - compressor i, +7.
Similarly, AC electric power (λM 3 and +7: 3!'(
1; Tue Cl) 31. 2.1. (Third “Electric”) 1-
1111 (+4) each AC motor M1
．． M2. M3 is the switch S1. S2 and 83 are connected to a common inverter IV.

−・般に電動機を全電圧）いわゆるＩ°１人、！１姶動
う、−すると、第３図に承りように定格電流ＩＲの数ｆ
Ｒに達づる大きな始動゛電流Ｉｓが流れる。この仝電月
−始動は大容作の電源を必要と覆るばかに電動機自体に
も大きな機械的ショックを！うえるのてりｆＡ、しくな
い。-・generally the electric motor at full voltage) so-called I°1 person,! If it moves by 1, then the number f of the rated current IR as shown in Figure 3.
A large starting current Is reaching R flows. Starting this electric motor requires a large power source, and it also causes a large mechanical shock to the electric motor itself! Ueru no teri fA, it's not good.

てこで４１独の電動１■縮槻の始動時にＩＪ、制り１１
の筒中なインバータの特性を活用して低周波低電圧で始
動し、始動電流を抑制しながら定格周波数定格電圧にま
で゛雪片対周波数比（づなわちＶ／Ｆ比）をはけ一定に
保ちながら変化させて定格速曵にまで速度上？１ざぜる
、いわゆる（Ｉ（周波始動方式が採用されている。Lever 41 German electric 1■ IJ, control 11 when starting the shingles
Utilizing the characteristics of the inverter in the cylinder, it starts at low frequency and low voltage, and while suppressing the starting current, it maintains a constant snowflake-to-frequency ratio (i.e., V/F ratio) up to the rated frequency and rated voltage. While changing the speed up to the rated speed? A so-called (I) frequency starting method is adopted.

しかしながら、たとえば第１の電動圧縮機の運転中に第
２あるい（よ第３の電動圧縮機を並列運転に入れるべく
、第１の電動圧縮機を定常状態で運転しでいるときに第
２あるいは第３の電動圧縮機を投入したのではやはり第
２あるいは第３の電動圧縮機が金貨ｊ「始動になること
に変わりがなく、やはり電源容量を大ぎくづるなどの対
策が必要になる。However, for example, in order to put the second or third electric compressor into parallel operation while the first electric compressor is operating, the second or third electric compressor may be operated in a steady state. Alternatively, if a third electric compressor is installed, the second or third electric compressor will still start up, and countermeasures such as increasing the power supply capacity will still be necessary.

〔発明のし）的〕[Target of invention]

本発明は以」−述べた小情を考慮してなされたもので、
−・部のｉｌＷ動１−「縮（幾の運転中に他の電動圧縮
機を並列投入Ｕるどぎに生ずる土間不都合を除去し、雷
源容ｔｒＩをどくに大ぎくしたりりること＜’ｆ　＜円
滑１．ｃ　ｊｌｆ１列投入運転を可能とりるＩｌ（！列
投入運転力法を提供りることにある。The present invention has been made in consideration of the considerations mentioned below.
-・Department's IlW operation 1- "Remove the inconvenience of dirt floor that occurs when other electric compressors are connected in parallel during operation, and make the lightning source capacity trI very large. 'f < Smooth 1.c jlfThe objective is to provide a method of driving power for 1-row operation.

（発明の概要） 上記目的を）１成づるために本発明は、共通のインバー
タにＪ、って駆動される複数台の電動圧縮機のうちの一
部の電動圧縮機の運転中に他の電動ロー縮機を並列投入
づるに際して、運転中の電Ｅｌｌ　Ｂ、　ｌｌ？ｉはを
一旦停」１し、並列運転ずべき複数台の電動１■縮槻を
前記インバータにより同時に低周波始動ｊＪることを狛
徴どりるものである。その場合、−４１停止した電動圧
１Ｉｉｉ機の圧力がバランス状態に近い状態になってか
ら複数台の電動圧縮（幾の同時低周波始動をした方が始
動電流をより小さくづる怠味で望ましい。(Summary of the Invention) In order to achieve the above object (1), the present invention provides a method for achieving the above object (1). When connecting electric low compressors in parallel, check if the electric current in operation is Ell B, ll? This command is used to temporarily stop the power supply 1 and simultaneously start a plurality of electric compressors that are to be operated in parallel at a low frequency using the inverter. In that case, it is preferable to start multiple electric compressors at a low frequency at the same time after the pressure of the electric compressor 1IIII, which has been stopped at -41, reaches a state close to a balanced state, since this reduces the starting current.

〔発明の実施例〕[Embodiments of the invention]

以■り、図面を参照しＣ本発明をさらに詳細に説明づる
。The present invention will now be described in more detail with reference to the drawings.

いま、初期状態として、第２図に、Ｊ３いて開閉器Ｓ１
．Ｓ２．Ｓ３が１べて開路されている状態、づなわちＪ
べての電動圧縮機が休止されＣいる状態を考える。Now, as an initial state, in Fig. 2, J3 and switch S1 are connected.
．． S2. A state where all S3 are open, that is, J
Consider a situation in which all electric compressors are stopped.

最初に空調負荷が小さく第１の電動圧縮機のみを運転す
るものと覆る。第１図のモード■に示づＪ、うにインバ
ータＩＶを低周波低電圧に設定し、開閉器＄１を投入し
て電動機Ｍ１を低周波始動づる。次いで図示のごと＜Ｆ
／Ｖ比をほぼ−・定に保ちながらインバータ周波数ｄ′
３よび電圧を徐々に−Ｆ昇させ、それに応じて電動機Ｍ
１および圧縮機ＣＰ１を徐々に速度上昇さけ、定格値で
定常運転に入る。このときの電動機電流は第４図のよう
に推移し、始動電流ＩＳが定格電流ＩＲを超えることは
ない。Initially, the air conditioning load is small and only the first electric compressor is operated. In mode J shown in FIG. 1, the inverter IV is set to low frequency and low voltage, and the switch $1 is turned on to start the electric motor M1 at a low frequency. Then, as shown <F
Inverter frequency d' while keeping the /V ratio almost constant.
3 and the voltage is gradually increased by -F, and the motor M is increased accordingly.
1 and compressor CP1 gradually increase in speed and enter steady operation at the rated values. At this time, the motor current changes as shown in FIG. 4, and the starting current IS never exceeds the rated current IR.

次に空調負狗の増大に伴い、第２の電動圧縮機を並列投
入する場合を考える。このときは、第１図のモードＨに
承りように、まず開閉器Ｓ１を開路して運転中の電動＋
ｊ３１Ｍ１（おＪ、び圧縮（顔ＣＰ　１　）を−・■」
停止トシ、インバータ周波数を下げるととｂにｆｌＥ　
１１８１３３１　ＣＩ）１の圧力バランス時間Ｌ（はば
１分程度）を待−〕−（聞開閉器１．Ｓ２を投入し、電
動＋幾Ｍ１．Ｍ２を同時に低周波始動づる。周知のごと
く運φル中の圧縮機を停止させた向後は圧力がアンバラ
ンス状態にあって電動機側から見た負荷１〜ルクが大き
く、イの状態で（すなわら圧縮１幾を停止したｉａ後に
）再始動し！このでは、第５図に示１１ように、低周波
始動方式によっても全電圧始動時よりは小さいとはいえ
、定格電流を超える比較的太さｔｉ始動電流が比較的長
い時間にわたって流れるので好ましくない。しかし、前
述のごとく圧縮ｉｆｆの圧力バランス時間を待つことに
Ｊ：り負？「７目〜ルクは減少し、第４図に示づような
望ましい始動電流のもとで電動機を始動させ、２絹の電
動圧縮（幾の並列運転に入ることができる。Next, consider the case where a second electric compressor is installed in parallel as the number of air conditioners increases. At this time, as in mode H in Fig. 1, first open switch S1 to
j31M1 (OJ, compression (face CP 1) -・■"
When the inverter frequency is stopped and the inverter frequency is lowered, flE
1181331 CI) 1) Wait for the pressure balance time L (approximately 1 minute). Turn on the switch 1.S2, and start the electric + gear M1.M2 at low frequency at the same time. As is well known, the operation φ After the compressor in the main compartment is stopped, the pressure is unbalanced and the load from the motor side is large. In this case, as shown in Figure 5 (11), even with the low frequency starting method, a relatively thick starting current that exceeds the rated current flows for a relatively long time, although it is smaller than when starting with full voltage. However, as mentioned above, waiting for the pressure balance time of the compression iff will reduce the torque and start the motor under the desired starting current as shown in Figure 4. It is possible to run two silks in parallel operation.

以下同様にして、第３の電動圧縮機をさらに並列投入覆
るときは、第１図の七−ド■に示゛づように、まず開閉
器Ｓｌ、Ｓ２を開路して第１および第２の電動圧縮機を
一旦停止づるとともに、インバータ周波数をＦＩｙる。In the same manner, when the third electric compressor is to be connected in parallel, first open the switches Sl and S2 to close the first and second electric compressors, as shown in Figure 1. Temporarily stop the electric compressor and change the inverter frequency to FIy.

圧縮機ＣＰ１．ＣＰ２の圧力バランス時間を待って開閉
器Ｓ１．Ｓ２゜＄３を投入し、３台の電動１１Ｍ１．Ｍ
２．Ｍ３を同時に低周波９（３動づればよい。Compressor CP1. Waiting for the pressure balance time of CP2, switch S1. Input S2゜$3 and use 3 electric 11M1. M
2. M3 at the same time as low frequency 9 (just move 3 times).

〔発明の効果〕〔Effect of the invention〕

以上述べｌ〔ように本発明によれば簡単な操作で、電源
容量を人さくしたり、系統に電気的ショックを与えたり
、さらには電動機もしくはそれに結合されている圧縮機
に機械的ショックを！ｊえたりすることなく、円滑な並
列投入運転を遂ｆ−ｊ−！ＩることがＣきる。As mentioned above, according to the present invention, with a simple operation, it is possible to reduce the power supply capacity, give an electric shock to the system, and even give a mechanical shock to the electric motor or the compressor connected to it! Achieve smooth parallel input operation without any disturbance! I can do C.

【図面の簡単な説明】[Brief explanation of the drawing]

第１図は本発明の並列投入運転方法を説明するだめのタ
イムチ１フート、 第２図は本発明を適用づる電動圧縮機群の電動機主回路
構成を示す接続図、 第３図は全電圧始動時の電動機の始動電流をポリ−タイ
ムチｔＩ−１へ、 第４図、第５図はそれぞれ本発明にＪ、る運転ｙ）法に
ｄ−３い（圧力バランス時間を考慮した口なと一８慮し
ないときの始動電流を示づタイムチレ−１−である。 ＩＶ・・・インバータ、Ｓｌ、３２．Ｓ３・・・開閉器
、Ｍｌ、Ｍ２．Ｍ３・・・交流電動放、ＣＩ〕１．ＣＲ
２゜Ｃ［）３・・・圧縮機、Ｉｓ・・・始動電流、ＩＲ
・・・定７１’＋　？Ｔ１流。 出願人代理人　　猪　　股　　　　積 重１図 一一□−Ｆ　　− 第　２図 第３図 第４Ｉ２１ 第５図Fig. 1 is a time diagram for explaining the parallel injection operation method of the present invention, Fig. 2 is a connection diagram showing the main circuit configuration of the motor of an electric compressor group to which the present invention is applied, and Fig. 3 is a full voltage starting Figures 4 and 5 show the starting current of the electric motor at the time of poly-time tI-1, respectively, according to the present invention. 8. It is a time delay-1- which shows the starting current when no consideration is given. IV... Inverter, Sl, 32. S3... Switch, Ml, M2. M3... AC electric discharge, CI]1. CR
2゜C[)3...Compressor, Is...Starting current, IR
...Constant 71'+? T1 style. Applicant's representative Inomata Stacking Figure 1 Figure 11 □-F - Figure 2 Figure 3 Figure 4I21 Figure 5

Claims (1)

【特許請求の範囲】 １、共通のインバータによって駆動される複数台の電動
圧縮機のうらの一部の電動圧縮機の運転中に他の電動圧
縮機を並列投入するに際して、運転中の電動圧縮機を一
旦停止し、並列運転すべき複数台の電動圧縮機を前記イ
ンバータにより同時に低周波始動することを特徴とする
並列運転される電動圧縮機群の並列投入運転方法。 ２、前記低周波始動を、一旦停止した電動圧縮機の圧力
がバランス状態に近い状態になってから行うことを特徴
とする特許請求の範囲第１項記載の並列投入運転方法。[Claims] 1. When one electric compressor at the back of a plurality of electric compressors driven by a common inverter is turned on in parallel with another electric compressor, the electric compressor during operation 1. A method for parallel start-up operation of a group of electric compressors operated in parallel, characterized in that the compressors are temporarily stopped and a plurality of electric compressors to be operated in parallel are simultaneously started at low frequency by the inverter. 2. The parallel start-up operation method according to claim 1, wherein the low frequency starting is performed after the pressure of the once stopped electric compressor reaches a state close to a balanced state.