JPS6099974A - Method of measuring degree of overheat - Google Patents

Abstract

(57)【要約】本公報は電子出願前の出願データであるた
め要約のデータは記録されません。(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

【発明の詳細な説明】 （イ）産業上の利用分野 −ｋＪ＃）ＩＬＪ　１．−？１ｍ、４７　＝ヒ創出巨血
　マＮｈ萌すｄＩＬｌ−／ｊ；１１４外、Ｊｓ　−ス式
電動弁等減圧機構を備えた電動弁を具備してなる冷凍装
置の過熱度測定方法に関する。[Detailed description of the invention] (a) Industrial application field - kJ#) ILJ 1. −? 1m, 47 = Hi Creation Giant Blood Ma Nh Moesu dILl-/j;114 Extra, Js - This invention relates to a method for measuring the degree of superheating of a refrigeration system equipped with a motor-operated valve equipped with a pressure reducing mechanism such as a Js-type motor-operated valve.

（ロ）従来技術 温度式膨張弁による過熱度制御の方法としては。(b) Conventional technology As a method of controlling the degree of superheating using a thermostatic expansion valve.

利用側熱交換器の蒸発圧力の圧力損失で、過熱度の受け
る影響が設定値より測定値が成る偏差例えばｌ　ｄｔｇ
以内若しくは等しい場合には、過熱度制御に差し支えな
い圧力損失なので内部均圧式の温度式膨張弁を用いるが
、ｌ　ｒｉｇ以上の場合には、圧力損失公文過熱度が大
きくなり過熱度の目標値が定まらないため外部均圧式の
温度式膨張弁を用いる方法をとっている。上記偏差が成
る幅以上になると、過熱度の測定値が設定値＋圧力損失
値となり、サクションガスの過熱・対数平均温度の上昇
が発生するため、外部均圧式のもので圧力損失を補正す
る必要が生じた。Due to the pressure loss of the evaporation pressure of the heat exchanger on the user side, the influence of the degree of superheating is the deviation in which the measured value is less than the set value.For example, l dtg
If the pressure loss is within or equal to the degree of superheating, an internal pressure-equalizing temperature-type expansion valve is used because the pressure loss does not interfere with superheat degree control. However, if the pressure loss is greater than l rig, the Kumon degree of superheating becomes large and the target value of the degree of superheating is Since this cannot be determined, a method is used that uses an external pressure-equalizing temperature-type expansion valve. If the above deviation exceeds the range, the measured superheat value will be the set value + the pressure loss value, causing overheating of the suction gas and an increase in the logarithmic average temperature, so it is necessary to correct the pressure loss with an external pressure equalization type. occurred.

この温度式膨張弁は減圧能力が同じであっても過熱度の
測定値が異なるために、内部均圧式か外部均圧式かの倒
れかを選択して使い分けなければｔｒｔ＋イ１．ｆｅｚ
Ｌ？ｆＩ１１’＋’Ｐイｉ＊ｈＺｌ−ｆ：’ｈ’ｆ”’
１１）４’、ニジ：ｈ、Ａｆ−Ｈ）Ｖこの圧力を温度に
換算して目標値を得る作業を強いられる欠点が生じた。These temperature-type expansion valves have different superheat measurements even if they have the same pressure-reducing capacity, so you have to choose between an internal pressure equalization type and an external pressure equalization type. fez
L? fI11'+'Pii*hZl-f:'h'f'''
11) 4', Niji:h, Af-H)VThere was a drawback that it was necessary to convert this pressure into temperature to obtain the target value.

（ハ）発明の目的 本発す」は冷凍装置の利用側熱交換器の蒸発発力の圧力
損失分を温度でもって表わし、制御すべき過熱度を算出
することを目的とする。(c) Purpose of the Invention The object of the present invention is to express the pressure loss of the evaporative power of the heat exchanger on the user side of a refrigeration system in terms of temperature, and calculate the degree of superheating to be controlled.

に）発明の構成 目標値となる過熱度を、圧力損失がある場合のサクショ
ン温度から圧力損失が過熱度制御に影響を与えない場合
の蒸発温度を減算して測定する過熱度の測定方法。B) A method for measuring the degree of superheat, which is the target value of the invention, by subtracting the evaporation temperature when the pressure loss does not affect superheat control from the suction temperature when there is a pressure loss.

（ホ）発明の実施例 第１図に示す（１）は冷蔵庫、エアコン等冷凍、空調機
器に使用される冷凍装置で、冷媒圧縮機（２）、熱源側
熱交換器（敏減圧機構を備えた電動弁（４）、送風機（
５）によって強制通風されるプレートフィン型の利用側
熱交換器（６）等を配管によって環状接続することによ
り構成され、例えばＲ２１’）、冷媒を封入し、この冷
媒の圧縮、凝縮液化、減圧、蒸発気化させる周知の冷凍
サイクルを形成する。（力は冷媒の蒸発温度（ＥＴ）を
検出するセンサー、（８）は冷媒のサクション温度（Ｓ
Ｔ）を検出するセンサーで、この両センサーからの温度
信号を図示しない制御器本体に送り、この本体からの制
御信号（Ｇ）によって電動弁（４）の開閉度の調整を図
る。(e) Embodiment of the Invention (1) shown in Figure 1 is a refrigeration system used in refrigeration and air conditioning equipment such as refrigerators and air conditioners, and is equipped with a refrigerant compressor (2), a heat source side heat exchanger (with a rapid depressurization mechanism) electric valve (4), blower (
It is constructed by connecting a plate-fin-type user-side heat exchanger (6), etc., which are forcedly ventilated by 5), etc. in a ring with piping, for example, R21'), which encloses a refrigerant, and compresses, condenses, liquefies, and depressurizes the refrigerant. , forming the well-known refrigeration cycle of evaporation. (Power is a sensor that detects the evaporation temperature (ET) of the refrigerant, (8) is the suction temperature (S) of the refrigerant.
Temperature signals from these two sensors are sent to a controller main body (not shown), and the opening/closing degree of the electric valve (4) is adjusted by a control signal (G) from this main body.

上記電動弁は特公昭５８−７８６９号公報で紹介された
［電気加熱手段を有するバイメタル式熱応動弁」及び月
刊紙「冷凍」の第５６巻第６４１号（昭和５６年３月号
）の第６０頁〜第６４頁に紹介された「熱電式膨張弁］
であり、前記制御信号を通電部となる加熱装置に印加し
てバイメタルを変位させ、弁体を上下方向に作動せしめ
るものである。The above-mentioned motorized valve was introduced in Japanese Patent Publication No. 58-7869 [Bimetallic Heat-Responsive Valve with Electric Heating Means] and in Volume 56, No. 641 (March 1986 issue) of the monthly newspaper "Refrigeration". “Thermoelectric expansion valve” introduced on pages 60 to 64
The control signal is applied to a heating device serving as a current-carrying portion to displace the bimetal and operate the valve body in the vertical direction.

第２図は上記冷凍装置におけるモリニル脚間を示す。第
２図において、（９）は朗相蒸気線、００）は飽和液線
、０υは臨界点、（５）〜（Ｃ，）は圧力（Ｐ、）及び
温度（ＥＴ）を有する等圧線０渇で表わされる蒸発気化
過程、（Ｃ１）〜（Ｄυは等エントロビイ＆（１３１で
表わされる圧縮過程、（Ｄｌ）〜（匂は等圧線０（イ）
で表わされる凝縮液化過程、（ｕ〜囚は等エンタルビイ
ａ！５）で表わされる減圧過程で、この圧力エンタルビ
イ線図は蒸発圧力（Ｐｌ）に圧力損失が殆んど生じない
、又生じたとしても過熱度制御に影響を与えない理想的
なものである。この圧力エンタルビイに於ける過熱度（
ＳＨ，）は酊可の幅で表わされる。FIG. 2 shows the space between the molinyl legs in the above-mentioned refrigeration system. In Figure 2, (9) is the positive phase vapor line, 00) is the saturated liquid line, 0υ is the critical point, and (5) to (C,) are isobar lines with pressure (P, ) and temperature (ET). Evaporation process represented by (C1) ~ (Dυ is isentrobi & (131) compression process, (Dl) ~ (odor is isobar line 0 (a)
In the condensation and liquefaction process expressed by , and the depressurization process expressed as It is also ideal as it does not affect superheat control. The degree of superheating in this pressure enthalby (
SH,) is expressed as a drunken width.

尚、（１６）〜α→は等製線であるっ 然し乍ら、冷凍装置（１）にお、いては冷媒の鍾類、蒸
発温度、配管の長さ等によって蒸発圧力に圧力損失が生
じ、その圧力が降下するのが一般的である。Although (16) ~ α→ is an isometric line, in the refrigeration system (1), pressure loss occurs in the evaporation pressure due to the type of refrigerant, the evaporation temperature, the length of the piping, etc. A drop in pressure is common.

即ち、上記圧力損失による圧力降下は利用側熱交換器（
６）の入口黒人から冷媒圧縮機（２）の入口点（Ｃ２）
にかげて発生し、（Ｐ、）の圧力を有する蒸発圧力αり
となる。この場合の過熱度（Ｓｌ（、）は票の幅で表わ
される。従って、蒸発圧力（Ｒ２）においては過熱度（
ＳＨ２）を補正する必要がある。In other words, the pressure drop due to the above pressure loss is reduced by the heat exchanger on the user side (
6) Inlet point of refrigerant compressor (2) from inlet black (C2)
evaporation pressure α with a pressure of (P,). The degree of superheat (Sl(,) in this case is expressed by the width of the vote. Therefore, at the evaporation pressure (R2), the degree of superheat (Sl(, )) is expressed by the width of the vote.
SH2) needs to be corrected.

尚、罎は蒸発圧力（Ｐ、）の変化に伴ない（Ｃ２）〜（
Ｄ２）に移項する等エントロビイ線である。In addition, as the evaporation pressure (P, ) changes, the capacitance changes from (C2) to (
This is an isentropic line that transfers to D2).

上記冷凍装置における過熱度制御の方法としては、過熱
度の設定値（ＳＨ，）と測定値（ＳＨＭ）との間に生じ
る偏差（ＤＥＶ）をなくす様電動弁（４）を自動制御さ
せることが望ましい。即ち、 ＤＥＶ＝ＳＨ，−８Ｈ。As a method for controlling the degree of superheat in the above-mentioned refrigeration system, it is possible to automatically control the electric valve (4) to eliminate the deviation (DEV) that occurs between the set value (SH,) and the measured value (SHM) of the degree of superheat. desirable. That is, DEV=SH, -8H.

として表わせ、又測定値は。Express it as , and the measured value is .

ＳＨ，＝ＳＴ−ＩＴ−△Ｐ）又は 上記の如く過熱度はＳＨ，＝Ｂ、Ｃ，の如（蒸発圧力（
Ｐｌ）が変化しないのが理想的で望ましいが、実際には
５Ｈ２＝Ｌｌ、（の如く利用側熱交換器（６）における
圧力損失により蒸発圧力がＲ２の如く降下するため、測
定値（Ｓｆｌ、４）は見かけ上太ぎ（なっている。即ち
、圧力損失の温度換算直火増加しており１ 、ＳＨ，＝ＳＴ−（ＥＴ−ΔＰ）又は、ＳＩ（、＝ＳＴ
十ΔＰ−ＥＴ として表わすことができる。SH, =ST-IT-△P) or as above, the degree of superheat is SH, =B,C, (evaporation pressure (
Ideally, it is desirable that Pl) does not change, but in reality, the evaporation pressure drops as R2 due to the pressure loss in the heat exchanger (6) on the utilization side, as shown in 5H2 = Ll, so the measured value (Sfl, 4) is apparently thicker (i.e., the pressure loss is increased in terms of temperature), and SH,=ST-(ET-ΔP) or SI(,=ST
It can be expressed as 1ΔP-ET.

尚、第２図においては、蒸発温度（ＥＴ）が、Ｂ。In addition, in FIG. 2, the evaporation temperature (ET) is B.

点又はＢ２点に相当し、又サクション温度（ＳＴ）が０
１点又は０２点に相当する。point or B2 point, and the suction temperature (ST) is 0.
Equivalent to 1 point or 02 points.

これらの関係を式で表わせば、測定値ＳＨＭは、ＳＨう
＝ＳＨ２ニ酊璽＝１で７＋△Ｐ となり、この式において、圧力降下の温度換算値ΔＰは
冷媒の種類、蒸発温度、配管の長さ等による内部抵抗に
より異なるが、 ΔＰ＝Ｐ、　（ａｉ！、Ｂｌ）−Ｐ、（αｉ！Ｂ２）と
なり、ここで八Ｐをなくす処理を施せばよい。Expressing these relationships in a formula, the measured value SHM is 7 + △P where SH = SH2 = 1. In this formula, the temperature conversion value ΔP of pressure drop is determined by the type of refrigerant, evaporation temperature, and piping. Although it varies depending on the internal resistance due to the length etc., ΔP=P, (ai!, Bl)-P, (αi!B2), and it is sufficient to perform processing to eliminate 8P here.

その方法については後述する。The method will be described later.

いま、Ｂ１点における蒸発温度ＥＴをＴ、　、Ｃ。Now, the evaporation temperature ET at point B1 is T, ,C.

点におけるサクション温度をＴ、　＋ＳＨｓ’、Ｂ２点
における蒸発温度ＥＴをＴ２．０２点におけるサクショ
ン温度ＥＴをＴ２＋ＳＩ（、とし、ＳＨ，＝　５　Ｃ１
ｅｌと設定して圧力損失のない場合のｊＭ熱度の目標値
と、ある場合の過熱度の目標値とを算出、すると、圧力
損失のない場合、 ５Ｈ＝ＳＴ−ＥＴ ｉｆ：（ＴＩ＋５）　ＴＩ ＝　５　ｄ、ｅｇ として算出でき、ＳＨ二Ｓ　Ｈ，であることが分かる。The suction temperature at point T, +SHs', the evaporation temperature ET at point B2 is T2. The suction temperature ET at point 2 is T2+SI(, SH, = 5 C1
el and calculate the target value of jM degree of heat when there is no pressure loss and the target value of degree of superheat when there is, then, when there is no pressure loss, 5H=ST-ET if: (TI+5) TI = It can be calculated as 5 d,eg, and it can be seen that SH2SH.

又、圧力損失のある場合、 ＳＨ二５Ｔ−ＥＴ ＝　（Ｔｔ　＋　５　）　Ｔ＋ ＝５　＋　（Ｔ２−ＴＩ　） Ｃ’ｒ＋＞’ｒｔ〕 となり、測定値３１（、＝　’Ｌ’２−　Ｔ、を温度と
して表わすことができる。こ〜で、Ｔ２−ＴＩ　＝　１
　ｄｅｇとすると、 ＳＨ＝５−１ ＝４ｄｇｙ となり、目標値ＳＨを温度で算出することができる。In addition, when there is pressure loss, SH25T-ET = (Tt + 5) T+ =5 + (T2-TI) C'r+>'rt], and the measured value is 31 (, = 'L'2-T, can be expressed as a temperature. Here, T2-TI = 1
deg, then SH=5-1=4dgy, and the target value SH can be calculated using the temperature.

尚、上記ΔＰをなくす処理としては、 ■　過熱度Ｓｌ（設定の際に Ｓ　Ｈ二ＳＨ，十ΔＰ 即ち設定値ＳＨ，に反力降下の温度換算値ΔＰを予じめ
加算する。Note that the process for eliminating the above ΔP is as follows: (1) The temperature conversion value ΔP of the reaction force drop is added in advance to the superheat degree SL (S H2SH, 10ΔP, ie, the set value SH, at the time of setting).

■　温度信号変換時に下記■■■の如くΔＰをキャンセ
ルする ■　Ｖ（ＥＴ）＋ΔＰ ■　Ｖ（ＳＴ）−ΔＰ ■　Ｖ（ＳＨ）−八Ｐ 〔Ｖ：温度信号の電圧値（測定値ＳＨＭで変換）〕等、
第３図に示す方法が考えられる。■ When converting the temperature signal, cancel ΔP as shown below ■ V (ET) + ΔP ■ V (ST) - ΔP ■ V (SH) - 8P [V: Voltage value of temperature signal (converted with measured value SHM) )〕etc,
A method shown in FIG. 3 can be considered.

（へ）効果 以上の如く本発明は目標値となる過熱度を、圧力損失が
ある場合のサクション温度から圧力損失が過熱度制御に
影響を与えない場合の蒸発温度を減算して測定するので
、下記に列挙する効果を奏する。(f) Effects As described above, the present invention measures the target superheat degree by subtracting the evaporation temperature when pressure loss does not affect superheat degree control from the suction temperature when there is pressure loss. It produces the effects listed below.

■　蒸発圧力の圧力損失を温度でもって測定でき、過熱
度の目標値の算出メ′極めて簡単に行なえると共に、過
熱度の補正が容易となり、適切な過熱度制御が可能とな
った。■ Pressure loss of evaporation pressure can be measured by temperature, calculation of target value of degree of superheat can be done extremely easily, correction of degree of superheat can be easily performed, and appropriate degree of superheat can be controlled.

■　温度式膨張弁における内部均圧式、外部均圧式の区
別をすることがないので、電動弁の利用範囲が広くなり
、取扱い易くなった。■ Since there is no need to distinguish between internal pressure equalization type and external pressure equalization type in temperature-type expansion valves, the range of use of motor-operated valves has been expanded and it has become easier to handle.

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

第１図は本発明過熱度の測定方法にか〜る冷凍装置の冷
媒回路図、第２図は冷凍装置におけるモリエル線図、第
３図は圧力降下の温度換算値のキャンセルを説明するブ
ロック図である。 第１Ｖ４１ 第２１゛４ エンタノＬビイ　１ 第３１￥ＩFig. 1 is a refrigerant circuit diagram of a refrigeration system according to the superheat measurement method of the present invention, Fig. 2 is a Mollier diagram of the refrigeration system, and Fig. 3 is a block diagram illustrating cancellation of the temperature conversion value of pressure drop. It is. 1st V41 21st 4 Entano L Bii 1 31st ￥I

Claims (1)

【特許請求の範囲】 １、電動弁でもって減圧した液冷媒を利用側熱交換器に
供給する冷凍装置において、冷媒の蒸発圧力に、過熱度
制御に影響を与える圧力損失が発生した場合に、目標値
となる過熱度ＳＨを、５Ｈ＝ＳＴ−ＥＴ ＝（Ｔ２　＋　ＳＨ−）　ＴＩ ＝ＳＨ，＋　（Ｔ２−’ｒ、　） の式で算出してなる過熱度の測定方法。[Claims] 1. In a refrigeration system that supplies liquid refrigerant whose pressure has been reduced by an electric valve to a user-side heat exchanger, when a pressure loss occurs in the evaporation pressure of the refrigerant that affects superheat degree control, A method for measuring the degree of superheat by calculating the target value of the degree of superheat SH using the following formula: 5H=ST-ET=(T2+SH-)TI=SH,+(T2-'r, ).