JP7379846B2 - heat pump cycle equipment - Google Patents

heat pump cycle equipment Download PDF

Info

Publication number
JP7379846B2
JP7379846B2 JP2019063187A JP2019063187A JP7379846B2 JP 7379846 B2 JP7379846 B2 JP 7379846B2 JP 2019063187 A JP2019063187 A JP 2019063187A JP 2019063187 A JP2019063187 A JP 2019063187A JP 7379846 B2 JP7379846 B2 JP 7379846B2
Authority
JP
Japan
Prior art keywords
refrigerant
degree
water
temperature
heat exchanger
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
JP2019063187A
Other languages
Japanese (ja)
Other versions
JP2020165540A (en
Inventor
稔久 冨田
将典 野口
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Fujitsu General Ltd
Original Assignee
Fujitsu General Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Fujitsu General Ltd filed Critical Fujitsu General Ltd
Priority to JP2019063187A priority Critical patent/JP7379846B2/en
Publication of JP2020165540A publication Critical patent/JP2020165540A/en
Application granted granted Critical
Publication of JP7379846B2 publication Critical patent/JP7379846B2/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Landscapes

  • Steam Or Hot-Water Central Heating Systems (AREA)
  • Air Conditioning Control Device (AREA)

Description

本発明は、ヒートポンプサイクル装置に係わり、詳細には、冷媒と熱交換を行って加熱した温水を利用側ユニットに供給するヒートポンプサイクル装置に関する。 The present invention relates to a heat pump cycle device, and more particularly to a heat pump cycle device that supplies hot water heated by exchanging heat with a refrigerant to a user unit.

ヒートポンプサイクル装置において、利用側熱交換器が冷媒と水とを熱交換させる水冷媒熱交換器であり、この水冷媒熱交換器と床暖房装置やラジエタといった暖房ユニットや温水を貯留する貯湯タンクなどの利用側ユニットとを水配管で接続して形成される温水回路を備え、水冷媒熱交換器で加熱した温水を温水回路を循環させて利用側ユニットに供給するものが知られている。このようなヒートポンプサイクル装置として、水冷媒熱交換器の冷媒出口側における冷媒過冷却度(以降、実冷媒過冷却度と記載する)が、圧縮機の回転数と水冷媒熱交換器における凝縮圧力とに基づいて定められた目標冷媒過冷却度となるように膨張弁の開度が調整されることで、COP(Coefficient Of Performanceの略。エネルギー消費効率)値の最大化を実現するものが提案されている(例えば、特許文献1を参照)。 In a heat pump cycle device, the user-side heat exchanger is a water-refrigerant heat exchanger that exchanges heat between the refrigerant and water, and the water-refrigerant heat exchanger is connected to a heating unit such as a floor heating device or radiator, a hot water storage tank that stores hot water, etc. It is known to include a hot water circuit formed by connecting a user unit with a water piping, and to circulate hot water heated by a water-refrigerant heat exchanger through the hot water circuit to supply the user unit. In such a heat pump cycle device, the degree of subcooling of the refrigerant at the refrigerant outlet side of the water-refrigerant heat exchanger (hereinafter referred to as the actual degree of subcooling) is determined by the rotation speed of the compressor and the condensation pressure in the water-refrigerant heat exchanger. The proposed method maximizes the COP (Coefficient of Performance) value by adjusting the opening degree of the expansion valve to achieve the target refrigerant subcooling degree determined based on (For example, see Patent Document 1).

特開2011-69570号公報Japanese Patent Application Publication No. 2011-69570

ところで、特許文献1で提案されているヒートポンプサイクル装置では、水冷媒熱交換器と利用側ユニットが接続される温水回路における、単位時間当たりの水の流量(以降、単に「流量」と記載する場合がある)の変化がCOP値に与える影響については言及されていない。上述した、水冷媒熱交換器を有するヒートポンプサイクル装置では、温水回路に設けられる循環ポンプの回転数を変化させることによって、あるいは、ヒートポンプサイクル装置が設置される場所によって温水回路の水配管の長さや内径寸法が異なることにより、温水回路側の水の流量が変化することがあり、温水回路における水の流量の変化に応じて、利用側ユニットから水冷媒熱交換器に戻ってきた水の温度(以降、戻り温度と記載する)や利用側ユニットから温水回路に流出する水の温度(以降、往き温度と記載する)が変化する。 By the way, in the heat pump cycle device proposed in Patent Document 1, the flow rate of water per unit time (hereinafter simply referred to as "flow rate") in the hot water circuit where the water-refrigerant heat exchanger and the user-side unit are connected There is no mention of the effect of changes in COP values. In the above-mentioned heat pump cycle device having a water-refrigerant heat exchanger, the length of the water piping in the hot water circuit can be adjusted by changing the rotation speed of the circulation pump installed in the hot water circuit or by changing the location where the heat pump cycle device is installed. Due to the difference in inner diameter dimensions, the flow rate of water in the hot water circuit may change, and depending on the change in the flow rate of water in the hot water circuit, the temperature ( The temperature of the water flowing out from the user unit into the hot water circuit (hereinafter referred to as the outgoing temperature) changes.

一般的に、利用側ユニットで発揮される暖房能力や給湯能力は、温水回路における水の流量と、往き温度と戻り温度との温度差の積に比例する。言い換えれば、利用側ユニットで発揮される暖房能力や給湯能力を一定としたとき、往き温度と戻り温度との温度差は水の流量に反比例し、水の流量が増加すれば往き温度と戻り温度との温度差は小さくなり、水の流量が減少すれば往き温度と戻り温度との温度差は大きくなる。このとき、圧縮機の回転数が固定されていれば、水の流量が増加して温度差が小さくなるときは往き温度が低下し、水の流量が減少して温度差が大きくなるときは往き温度が上昇する。 Generally, the heating capacity and hot water supply capacity exhibited by the user-side unit are proportional to the product of the flow rate of water in the hot water circuit and the temperature difference between the outgoing temperature and the return temperature. In other words, when the heating capacity and hot water supply capacity exerted by the user unit are constant, the temperature difference between the outgoing temperature and the return temperature is inversely proportional to the water flow rate, and as the water flow rate increases, the outgoing temperature and return temperature increase. If the flow rate of water decreases, the temperature difference between the outflow temperature and the return temperature will increase. At this time, if the rotation speed of the compressor is fixed, when the water flow rate increases and the temperature difference decreases, the temperature will decrease; when the water flow rate decreases and the temperature difference increases, the temperature will decrease. Temperature rises.

以上に説明したように、温水回路における水の流量の変化に起因して往き温度が変化する。また、ヒートポンプサイクル装置では、往き温度が利用側ユニットで要求される暖房能力や給湯能力に応じて定められた目標温度となるように、圧縮機の回転数が制御される。特許文献1に記載のヒートポンプサイクル装置では、前述したように圧縮機の回転数と凝縮圧力とに基づいて目標冷媒過冷却度が定められており温水回路における水の流量は考慮されていない。従って、温水回路における水の流量が変化した場合は、実冷媒過冷却度が変更された圧縮機の回転数に基づいて決定された目標冷媒過冷却度となっても、COP値を最大化できない恐れがあった。 As explained above, the outgoing temperature changes due to a change in the flow rate of water in the hot water circuit. Furthermore, in the heat pump cycle device, the rotation speed of the compressor is controlled so that the outflow temperature reaches a target temperature determined according to the heating capacity and hot water supply capacity required by the user unit. In the heat pump cycle device described in Patent Document 1, as described above, the target refrigerant supercooling degree is determined based on the rotation speed and condensing pressure of the compressor, and the flow rate of water in the hot water circuit is not taken into consideration. Therefore, if the flow rate of water in the hot water circuit changes, the COP value cannot be maximized even if the actual refrigerant subcooling degree reaches the target refrigerant subcooling degree determined based on the changed compressor rotation speed. There was fear.

本発明は以上述べた問題点を解決するものであり、温水回路側の水の流量に関わらずCOP値を最大化できるヒートポンプサイクル装置を提供することを目的とする。 The present invention solves the above-mentioned problems, and aims to provide a heat pump cycle device that can maximize the COP value regardless of the water flow rate on the hot water circuit side.

本発明は上述の課題を解決するものであって、本発明のヒートポンプサイクル装置は、圧縮機と水冷媒熱交換器と膨張弁と熱源側熱交換器とが順次冷媒配管で接続された冷媒回路と、水冷媒熱交換器と利用側ユニットと循環ポンプとが順次水配管で接続された温水回路と、膨張弁の開度を調整する制御手段と、水冷媒熱交換器から流出する冷媒の温度である冷媒出口温度を検出する冷媒温度センサと、水冷媒熱交換器に流入する水の温度である戻り温度を検出する戻り温度センサと、水冷媒熱交換器が凝縮器として機能する際に、水冷媒熱交換器における冷媒の凝縮圧力を検出する凝縮圧力センサを有する。制御手段は、暖房運転を行っているとき、冷媒の凝縮圧力を用いて求めた冷媒の凝縮温度から冷媒出口温度を減じて求めた実冷媒過冷却度が、凝縮圧力と圧縮機の回転数に基づいて定められた目標冷媒過冷却度となるように、膨張弁の開度を調整し、目標冷媒過冷却度から実冷媒過冷却度を減じて求めた過冷却度差が所定範囲内の値であり、かつ、冷媒出口温度から戻り温度を減じて求めた温度差が第1所定値より大きい値である場合は、目標冷媒過冷却度に第2所定値を加算する。 The present invention solves the above-mentioned problems, and the heat pump cycle device of the present invention includes a refrigerant circuit in which a compressor, a water-refrigerant heat exchanger, an expansion valve, and a heat source side heat exchanger are sequentially connected by refrigerant piping. , a hot water circuit in which the water-refrigerant heat exchanger, the user-side unit, and the circulation pump are sequentially connected by water piping, a control means for adjusting the opening degree of the expansion valve, and a temperature control unit for the refrigerant flowing out from the water-refrigerant heat exchanger. A refrigerant temperature sensor detects the refrigerant outlet temperature which is , and a return temperature sensor which detects the return temperature which is the temperature of the water flowing into the water-refrigerant heat exchanger.When the water-refrigerant heat exchanger functions as a condenser, It has a condensation pressure sensor that detects the condensation pressure of the refrigerant in the water-refrigerant heat exchanger. The control means is configured to calculate, during heating operation, an actual degree of subcooling of the refrigerant obtained by subtracting the refrigerant outlet temperature from the condensation temperature of the refrigerant obtained using the condensation pressure of the refrigerant, based on the condensation pressure and the rotation speed of the compressor. The opening degree of the expansion valve is adjusted so that the target degree of refrigerant subcooling is determined based on the target degree of subcooling, and the difference in the degree of subcooling obtained by subtracting the actual degree of refrigerant subcooling from the target degree of refrigerant subcooling is a value within a predetermined range. And when the temperature difference obtained by subtracting the return temperature from the refrigerant outlet temperature is larger than the first predetermined value, the second predetermined value is added to the target refrigerant supercooling degree.

本発明のヒートポンプサイクル装置は、過冷却度差が所定範囲内の値であり、かつ、冷媒出口温度から戻り温度を減じて求めた温度差が第1所定値より大きい場合に、目標冷媒過冷却度に第2所定値を加算する。これにより、温水回路側の水の流量に関わらずCOP値を最大化できる。 In the heat pump cycle device of the present invention, when the subcooling degree difference is within a predetermined range and the temperature difference obtained by subtracting the return temperature from the refrigerant outlet temperature is larger than the first predetermined value, the target refrigerant subcooling A second predetermined value is added at each time. Thereby, the COP value can be maximized regardless of the water flow rate on the hot water circuit side.

本発明の実施形態における、ヒートポンプサイクル装置の構成図である。FIG. 1 is a configuration diagram of a heat pump cycle device in an embodiment of the present invention. 本発明の実施形態における、目標冷媒過冷却度テーブルである。It is a target refrigerant supercooling degree table in an embodiment of the present invention. 本発明の実施形態における、膨張弁の開度調整を行う際の処理の流れを説明するフローチャートである。It is a flowchart explaining the flow of processing when adjusting the opening degree of an expansion valve in an embodiment of the present invention.

以下、本発明の実施の形態を、添付図面に基づいて詳細に説明する。尚、本発明は以下の実施形態に限定されることはなく、本発明の主旨を逸脱しない範囲で種々変形することが可能である。 Hereinafter, embodiments of the present invention will be described in detail based on the accompanying drawings. Note that the present invention is not limited to the following embodiments, and various modifications can be made without departing from the spirit of the present invention.

図1は、本実施形態のヒートポンプサイクル装置であるヒートポンプ式温水暖房装置100の構成を示している。このヒートポンプ式温水暖房装置100は、圧縮機1と、四方弁2と、冷媒と水との熱交換を行う水冷媒熱交換器3と、膨張弁4と、熱源側熱交換器5と、アキュムレータ6とが順に冷媒配管11で接続された冷媒回路10を有する。また、ヒートポンプ式温水暖房装置100は、水冷媒熱交換器3と、流量計31と、室内ユニット40と、循環ポンプ30とが順に水配管16で接続された温水回路20を有する。さらに、ヒートポンプ式温水暖房装置100は、制御手段60を有する。 FIG. 1 shows the configuration of a heat pump hot water heating device 100, which is a heat pump cycle device of this embodiment. This heat pump type hot water heating device 100 includes a compressor 1, a four-way valve 2, a water-refrigerant heat exchanger 3 for exchanging heat between refrigerant and water, an expansion valve 4, a heat source side heat exchanger 5, and an accumulator. 6 and 6 have a refrigerant circuit 10 connected in order through refrigerant piping 11. The heat pump type hot water heating device 100 also includes a hot water circuit 20 in which a water refrigerant heat exchanger 3, a flow meter 31, an indoor unit 40, and a circulation pump 30 are connected in order through a water pipe 16. Furthermore, the heat pump type hot water heating device 100 has a control means 60.

<冷媒回路について>
まず、冷媒回路10を構成する装置や部材について説明する。圧縮機1は、インバータにより回転数が制御される図示しないモータによって駆動されることで、運転容量を可変できる能力可変型圧縮機である。四方弁2は、冷媒回路10における冷媒が循環する方向を切り換えるための弁である。水冷媒熱交換器3は、冷媒配管11を流れて水冷媒熱交換器3に流入した冷媒と水配管16を流れて水冷媒熱交換器3に流入した水とを熱交換させる。膨張弁4は、図示しないステッピングモータを用いてパルス制御により弁の開度を制御するものであり、水冷媒熱交換器3に流入あるいは水冷媒熱交換器3から流出する冷媒量を調整する。熱源側熱交換器5は、流入した冷媒と図示しないファンの回転により取り込まれた外気とを熱交換させる。アキュムレータ6は、四方弁2から流入した冷媒をガス冷媒と液冷媒に分離し、ガス冷媒のみを圧縮機1に吸入させる。
<About the refrigerant circuit>
First, the devices and members constituting the refrigerant circuit 10 will be explained. The compressor 1 is a variable capacity compressor whose operating capacity can be varied by being driven by a motor (not shown) whose rotation speed is controlled by an inverter. The four-way valve 2 is a valve for switching the direction in which the refrigerant in the refrigerant circuit 10 circulates. The water-refrigerant heat exchanger 3 exchanges heat between the refrigerant that has flowed through the refrigerant pipe 11 and has flowed into the water-refrigerant heat exchanger 3 and the water that has flowed through the water pipe 16 and flowed into the water-refrigerant heat exchanger 3 . The expansion valve 4 controls the opening degree of the valve by pulse control using a stepping motor (not shown), and adjusts the amount of refrigerant flowing into or flowing out from the water/refrigerant heat exchanger 3 . The heat source side heat exchanger 5 exchanges heat between the refrigerant that has flowed in and the outside air taken in by the rotation of a fan (not shown). The accumulator 6 separates the refrigerant that has flowed in from the four-way valve 2 into gas refrigerant and liquid refrigerant, and allows only the gas refrigerant to be sucked into the compressor 1.

また、冷媒回路10には、以下に説明する各種センサが設けられている。冷媒配管11における圧縮機1の吐出口付近には、圧縮機1から吐出された冷媒の圧力である吐出圧力を検出する吐出圧力センサ51と、圧縮機1から吐出された冷媒の温度である吐出温度を検出する吐出温度センサ52とが備えられている。冷媒配管11におけるアキュムレータ6の冷媒流入側付近には、圧縮機1に吸入される冷媒の圧力である吸入圧力を検出する吸入圧力センサ53と、圧縮機1に吸入される冷媒の温度である吸入温度を検出する吸入温度センサ54とが備えられている。なお、吐出圧力センサ51が本発明の凝縮圧力センサである。 Further, the refrigerant circuit 10 is provided with various sensors described below. Near the discharge port of the compressor 1 in the refrigerant pipe 11, there is a discharge pressure sensor 51 that detects the discharge pressure that is the pressure of the refrigerant discharged from the compressor 1, and a discharge pressure sensor 51 that detects the discharge pressure that is the pressure of the refrigerant discharged from the compressor 1. A discharge temperature sensor 52 for detecting temperature is provided. Near the refrigerant inlet side of the accumulator 6 in the refrigerant pipe 11, there is a suction pressure sensor 53 that detects the suction pressure, which is the pressure of the refrigerant sucked into the compressor 1, and a suction sensor 53, which detects the suction pressure that is the pressure of the refrigerant sucked into the compressor 1. An intake temperature sensor 54 for detecting temperature is provided. Note that the discharge pressure sensor 51 is the condensation pressure sensor of the present invention.

冷媒配管11における水冷媒熱交換器3の冷媒出口側付近には、暖房運転時に水冷媒熱交換器3から流出する冷媒の温度である冷媒出口温度を検出する冷媒温度センサ55が備えられている。冷媒配管11における膨張弁4と熱源側熱交換器5との間には、暖房運転時に熱源側熱交換器5に流入する冷媒の温度を検出する熱交温度センサ57が備えられている。そして、熱源側熱交換器5の近傍には、図示しない送風ファンの回転によって熱源側熱交換器5へと導かれる外気温度を検出するための外気温度センサ55が設けられている。 A refrigerant temperature sensor 55 is provided near the refrigerant outlet side of the water-refrigerant heat exchanger 3 in the refrigerant pipe 11 to detect the refrigerant outlet temperature, which is the temperature of the refrigerant flowing out from the water-refrigerant heat exchanger 3 during heating operation. . A heat exchanger temperature sensor 57 is provided between the expansion valve 4 and the heat source side heat exchanger 5 in the refrigerant pipe 11 to detect the temperature of the refrigerant flowing into the heat source side heat exchanger 5 during heating operation. An outside air temperature sensor 55 is provided near the heat source side heat exchanger 5 to detect the outside air temperature guided to the heat source side heat exchanger 5 by rotation of a blower fan (not shown).

<温水回路の構成について>
次に、温水回路20を構成する装置や部材について説明する。水冷媒熱交換器3は、例えば二重管熱交換器であり、一方の流路に冷媒配管11が接続され、他方の流路に水配管16が接続されている。循環ポンプ30は、図示しない回転数変更可能なモータによって駆動され、循環ポンプ30が駆動することで、温水回路20を図1に示す矢印80の方向に水が循環する。室内ユニット40は、床暖房装置やラジエタなどといった室内を暖房する暖房ユニットである。流量計31は、温水回路20における単位時間あたりの水の流量を計測する。なお、室内ユニット40が、本発明の利用側ユニットである。
<About the hot water circuit configuration>
Next, the devices and members constituting the hot water circuit 20 will be explained. The water-refrigerant heat exchanger 3 is, for example, a double-pipe heat exchanger, and has a refrigerant pipe 11 connected to one flow path and a water pipe 16 connected to the other flow path. The circulation pump 30 is driven by a motor (not shown) whose rotation speed can be changed, and when the circulation pump 30 is driven, water circulates through the hot water circuit 20 in the direction of an arrow 80 shown in FIG. 1 . The indoor unit 40 is a heating unit that heats the room, such as a floor heating device or a radiator. The flow meter 31 measures the flow rate of water in the hot water circuit 20 per unit time. Note that the indoor unit 40 is a user-side unit of the present invention.

また、温水回路20には、以下に説明する各種センサが設けられている。水配管16における水冷媒熱交換器3の水の出口側には、水冷媒熱交換器3から流出するする水の温度である往き温度を検出する往き温度センサ58が備えられている。水配管16における水冷媒熱交換器3の水の入口側には、水冷媒熱交換器3に流入する水の温度である戻り温度を検出する戻り温度センサ59が備えられている。 Further, the hot water circuit 20 is provided with various sensors described below. On the water outlet side of the water-refrigerant heat exchanger 3 in the water pipe 16, an outflow temperature sensor 58 is provided to detect an outflow temperature, which is the temperature of water flowing out from the water-refrigerant heat exchanger 3. A return temperature sensor 59 is provided on the water inlet side of the water-refrigerant heat exchanger 3 in the water pipe 16 to detect a return temperature, which is the temperature of the water flowing into the water-refrigerant heat exchanger 3.

<制御手段について>
次に、制御手段60について説明する。制御手段60は、それぞれ図示は省略するが、ヒートポンプ式温水暖房装置100の運転制御に関わる各種プログラムや後述する目標冷媒過冷却度テーブル200を記憶する記憶部と、上述した冷媒回路10や温水回路20に備えられた各種センサでの検出値を取り込むセンサ入力部と、室内ユニット40を操作するための図示しないリモコンから送信される信号を受信する受信部を有する。制御手段60は、各種センサで検出した値をセンサ入力部を介して取り込み、また、使用者のリモコン操作によって送信される室内ユニット40の運転に関わる各種要求を受信部を介して取り込む。そして、制御手段60は、取り込んだ各種センサで検出した値や運転に関わる各種要求に基づいて、圧縮機1や循環ポンプ30の駆動制御、四方弁2の切り換え制御、膨張弁4の開度調整などといった、ヒートポンプ式温水暖房装置100の各装置の制御を行う。
<About control means>
Next, the control means 60 will be explained. Although not shown, the control means 60 includes a storage unit that stores various programs related to the operation control of the heat pump type hot water heating device 100 and a target refrigerant supercooling degree table 200 to be described later, and the refrigerant circuit 10 and the hot water circuit described above. The indoor unit 20 includes a sensor input section that receives detection values from various sensors provided in the indoor unit 20, and a reception section that receives signals transmitted from a remote control (not shown) for operating the indoor unit 40. The control means 60 receives values detected by various sensors through a sensor input section, and also receives various requests related to the operation of the indoor unit 40 transmitted by a user's remote control operation through a reception section. The control means 60 controls the drive of the compressor 1 and the circulation pump 30, controls the switching of the four-way valve 2, and adjusts the opening of the expansion valve 4 based on the values detected by the various sensors and various requests related to operation. Each device of the heat pump type hot water heating device 100 is controlled.

<冷媒回路および温水回路の動作>
次に、本実施形態のヒートポンプ式温水暖房装置100が運転を行う際の、冷媒回路10における冷媒の流れや各部の動作、および、温水回路20における水の流れや各部の動作について、図1を用いて説明する。以下の説明では、ヒートポンプ式温水暖房装置100が暖房運転を行う場合について説明し、その他の運転、例えば、暖房運転中に熱源側熱交換器5で発生した霜を融かす除霜運転などについては、説明を省略する。
<Operation of refrigerant circuit and hot water circuit>
Next, FIG. 1 shows the flow of refrigerant and the operation of each part in the refrigerant circuit 10 and the flow of water and the operation of each part in the hot water circuit 20 when the heat pump hot water heating apparatus 100 of this embodiment operates. I will explain using In the following explanation, a case where the heat pump type hot water heating device 100 performs a heating operation will be explained, and other operations, such as a defrosting operation to melt frost generated in the heat source side heat exchanger 5 during the heating operation, will be explained. , the explanation is omitted.

ヒートポンプ式温水暖房装置100が暖房運転を行う場合は、制御手段60により四方弁2が操作されて冷媒回路10が暖房サイクルとされる。この状態で圧縮機1が駆動すると、冷媒回路10を図1に実線矢印70の方向に冷媒が流れる。具体的には、圧縮機1から吐出された冷媒は、冷媒配管11を流れて四方弁2を経て水冷媒熱交換器3に流入する。ここで、圧縮機1の回転数は、往き温度センサ58で検出する水温である往き温度が、室内ユニット40で使用者が要求する暖房能力に応じた目標往き温度となるように制御される。 When the heat pump type hot water heating device 100 performs heating operation, the four-way valve 2 is operated by the control means 60, and the refrigerant circuit 10 is set to a heating cycle. When the compressor 1 is driven in this state, refrigerant flows through the refrigerant circuit 10 in the direction of the solid arrow 70 in FIG. Specifically, the refrigerant discharged from the compressor 1 flows through the refrigerant pipe 11, passes through the four-way valve 2, and flows into the water-refrigerant heat exchanger 3. Here, the rotation speed of the compressor 1 is controlled so that the outlet temperature, which is the water temperature detected by the outlet temperature sensor 58, becomes a target outlet temperature according to the heating capacity requested by the user of the indoor unit 40.

水冷媒熱交換器3に流入した冷媒は、温水回路20を循環して水冷媒熱交換器3に流入した水と熱交換を行って凝縮する。水冷媒熱交換器3から冷媒配管11に流出した冷媒は、膨張弁4を通過する際に減圧されて熱源側熱交換器5に流入する。ここで、膨張弁4の開度は、水冷媒熱交換器3の冷媒出口側(暖房運転時の膨張弁4側)における冷媒過冷却度である実冷媒過冷却度が目標冷媒過冷却度となるように調整される。尚、目標冷媒過冷却度については、後に詳細に説明する。
熱源側熱交換器5に流入した冷媒は、外気と熱交換を行って蒸発する。熱源側熱交換器5から冷媒配管11に流出した冷媒は、四方弁2、アキュムレータ6を介して圧縮機1に吸入されて再び圧縮される。
The refrigerant that has flowed into the water-refrigerant heat exchanger 3 circulates through the hot water circuit 20, exchanges heat with the water that has flowed into the water-refrigerant heat exchanger 3, and is condensed. The refrigerant flowing out from the water-refrigerant heat exchanger 3 into the refrigerant pipe 11 is depressurized when passing through the expansion valve 4 and flows into the heat source side heat exchanger 5. Here, the opening degree of the expansion valve 4 is such that the actual refrigerant subcooling degree, which is the refrigerant subcooling degree on the refrigerant outlet side of the water-refrigerant heat exchanger 3 (the expansion valve 4 side during heating operation), is equal to the target refrigerant subcooling degree. It will be adjusted so that Note that the target refrigerant subcooling degree will be explained in detail later.
The refrigerant flowing into the heat source side heat exchanger 5 exchanges heat with the outside air and evaporates. The refrigerant flowing out from the heat source side heat exchanger 5 into the refrigerant pipe 11 is sucked into the compressor 1 via the four-way valve 2 and the accumulator 6, and is compressed again.

一方、温水回路20では、循環ポンプ30が駆動することで温水回路20を図1に示す実線矢印80の方向に水が流れる。水配管16を流れて水冷媒熱交換器3に流入した水は冷媒によって加熱されて温水となって、室内ユニット40に流入する。室内ユニット40に温水が流れることで、室内ユニット40が設置された部屋の暖房が行われる。 On the other hand, in the hot water circuit 20, the circulation pump 30 is driven so that water flows through the hot water circuit 20 in the direction of the solid line arrow 80 shown in FIG. The water flowing through the water pipe 16 and flowing into the water-refrigerant heat exchanger 3 is heated by the refrigerant, becomes hot water, and flows into the indoor unit 40. By flowing hot water to the indoor unit 40, the room in which the indoor unit 40 is installed is heated.

<目標冷媒過冷却度を用いた膨張弁の開度調整>
次に、図1および図2を用いて、本実施形態のヒートポンプ式温水暖房装置100が、暖房運転中に行う膨張弁4の開度調整について説明する。ヒートポンプ式温水暖房装置100が暖房運転を行っているとき、制御手段60は、吐出圧力センサ51で検出した吐出圧力を取り込み、取り込んだ吐出圧力を水冷媒熱交換器3における凝縮圧力とみなし、これを用いて暖房運転時に凝縮器として機能する水冷媒熱交換器3における凝縮温度を求め、求めた凝縮温度から冷媒温度センサ55で検出した冷媒出口温度を減じて、実冷媒過冷却度を算出する。そして、制御手段60は、算出した実冷媒過冷却度が、図2に示す目標冷媒過冷却度テーブル200に掲載された目標冷媒過冷却度となるように、膨張弁4の開度を調整する。
<Adjustment of expansion valve opening using target refrigerant subcooling degree>
Next, with reference to FIGS. 1 and 2, the opening degree adjustment of the expansion valve 4 performed by the heat pump hot water heating apparatus 100 of this embodiment during heating operation will be described. When the heat pump type hot water heating device 100 is performing heating operation, the control means 60 takes in the discharge pressure detected by the discharge pressure sensor 51, regards the taken-in discharge pressure as the condensation pressure in the water-refrigerant heat exchanger 3, and The condensation temperature in the water-refrigerant heat exchanger 3, which functions as a condenser during heating operation, is determined using . Then, the control means 60 adjusts the opening degree of the expansion valve 4 so that the calculated actual refrigerant subcooling degree becomes the target refrigerant subcooling degree listed in the target refrigerant subcooling degree table 200 shown in FIG. .

図2に示す目標冷媒過冷却度テーブル200は、予め試験などを行って求められて制御手段60に記憶されているものであり、この目標冷媒過冷却度テーブル200に記憶されている各目標冷媒過冷却度の値は、温水回路20における水の流量をある一定の値としたときに実冷媒過冷却度をこの目標冷媒過冷却度とすることで、暖房運転中のCOP値を最大化できるように定められている。なお、目標冷媒過冷却度テーブル200では、圧縮機1の回転数をR(単位:rps)、暖房運転中に凝縮器として機能する水冷媒熱交換器3における凝縮圧力をPc(単位:MPa)としている。 The target refrigerant subcooling degree table 200 shown in FIG. The COP value during heating operation can be maximized by setting the actual refrigerant subcooling degree to this target refrigerant subcooling degree when the flow rate of water in the hot water circuit 20 is set to a certain constant value. It is defined as follows. In addition, in the target refrigerant subcooling degree table 200, the rotation speed of the compressor 1 is R (unit: rps), and the condensation pressure in the water-refrigerant heat exchanger 3 that functions as a condenser during heating operation is Pc (unit: MPa). It is said that

目標冷媒過冷却度テーブル200では、圧縮機1の回転数Rと凝縮圧力Pcとに応じて複数の目標冷媒過冷却度が定められている。具体的には、圧縮機1の回転数Rが40rps未満である場合、凝縮圧力Pcの上昇時で3.0MPa未満/下降時で2.8MPaである場合の目標冷媒過冷却度が6deg、凝縮圧力Pcの上昇時で3.0MPa以上3.6MPa未満/下降時で2.8MPa以上3.4MPa未満である場合の目標冷媒過冷却度が10deg、凝縮圧力Pcの上昇時で3.6MPa以上/下降時で3.4MPaである場合の目標冷媒過冷却度が12degとされている。 In the target refrigerant subcooling degree table 200, a plurality of target refrigerant subcooling degrees are determined according to the rotation speed R of the compressor 1 and the condensing pressure Pc. Specifically, when the rotation speed R of the compressor 1 is less than 40 rps, when the condensing pressure Pc is less than 3.0 MPa when increasing/2.8 MPa when decreasing, the target refrigerant supercooling degree is 6 degrees, and the condensing The target refrigerant supercooling degree is 10 deg when the pressure Pc is 3.0 MPa or more and less than 3.6 MPa when the pressure Pc is rising / 2.8 MPa or more and less than 3.4 MPa when the pressure Pc is rising, and 3.6 MPa or more when the condensing pressure Pc is rising / The target degree of supercooling of the refrigerant is 12 deg when the pressure is 3.4 MPa during descent.

圧縮機1の回転数Rが40rps以上70rps未満である場合、凝縮圧力Pcの上昇時で3.0MPa未満/下降時で2.8MPaである場合の目標冷媒過冷却度が5deg、凝縮圧力Pcの上昇時で3.0MPa以上3.6MPa未満/下降時で2.8MPa以上3.4MPa未満である場合の目標冷媒過冷却度が8deg、凝縮圧力Pcの上昇時で3.6MPa以上/下降時で3.4MPaである場合の目標冷媒過冷却度が10degとされている。圧縮機1の回転数Rが70rps以上である場合、凝縮圧力Pcの上昇時で3.0MPa未満/下降時で2.8MPaである場合の目標冷媒過冷却度が4deg、凝縮圧力Pcの上昇時で3.0MPa以上3.6MPa未満/下降時で2.8MPa以上3.4MPa未満である場合の目標冷媒過冷却度が6deg、凝縮圧力Pcの上昇時で3.6MPa以上/下降時で3.4MPaである場合の目標冷媒過冷却度が7degとされている。 When the rotation speed R of the compressor 1 is 40 rps or more and less than 70 rps, the target refrigerant supercooling degree is 5 deg when the condensing pressure Pc is less than 3.0 MPa when rising/2.8 MPa when falling. When the target refrigerant supercooling degree is 8 degrees when it is 3.0 MPa or more and less than 3.6 MPa when rising / 2.8 MPa or more and less than 3.4 MPa when falling, the condensation pressure Pc is 3.6 MPa or more when rising / when falling The target refrigerant subcooling degree when the pressure is 3.4 MPa is 10 deg. When the rotation speed R of the compressor 1 is 70 rps or more, the target refrigerant supercooling degree is 4 deg when the condensing pressure Pc is less than 3.0 MPa when increasing/2.8 MPa when decreasing, and when the condensing pressure Pc is increasing When the target refrigerant supercooling degree is 3.0 MPa or more and less than 3.6 MPa/2.8 MPa or more and less than 3.4 MPa when falling, the target refrigerant supercooling degree is 6 deg, and when the condensing pressure Pc rises, it is 3.6 MPa or more/when falling it is 3. The target refrigerant supercooling degree in case of 4 MPa is 7 deg.

つまり、目標冷媒過冷却度テーブル200では、圧縮機1の回転数Rが高くなるのにつれて目標冷媒過冷却度の値が小さくなるように定められており、また、凝縮圧力Pcが高くなるのにつれて目標冷媒過冷却度の値が大きくなるように定められている。また、凝縮圧力Pcの上昇時と下降時で凝縮圧力Pcの範囲を定める値を異ならせているのは、実測した凝縮圧力Pcがこの範囲を定める値の付近の値を上下することによって目標冷媒過冷却度の値が頻繁に変化することに起因して膨張弁4の開度も頻繁に変化する、所謂制御のハンチングを防ぐためである。 That is, in the target refrigerant supercooling degree table 200, the value of the target refrigerant supercooling degree is determined to decrease as the rotation speed R of the compressor 1 increases, and as the condensing pressure Pc increases, The value of the target refrigerant subcooling degree is determined to be large. In addition, the reason why the value that defines the range of condensing pressure Pc is different when the condensing pressure Pc increases and decreases is that the actually measured condensing pressure Pc increases or decreases around the value that defines this range, and the target refrigerant This is to prevent so-called control hunting, in which the opening degree of the expansion valve 4 also changes frequently due to frequent changes in the value of the degree of supercooling.

ヒートポンプサイクル装置100が暖房運転を行っているとき、制御手段60は、前述した方法で実冷媒過冷却度を定期的(例えば、2分毎)に算出する。また、制御手段60は、実冷媒過冷却度を算出するタイミングに合わせて、現在の圧縮機1の回転数Rと吐出圧力センサ51で検出した吐出圧力を凝縮圧力Pcとして用い、目標冷媒過冷却度テーブル200を参照して目標冷媒過冷却度を選択する。 When the heat pump cycle device 100 is performing heating operation, the control means 60 calculates the actual refrigerant subcooling degree periodically (for example, every 2 minutes) using the method described above. Further, the control means 60 uses the current rotational speed R of the compressor 1 and the discharge pressure detected by the discharge pressure sensor 51 as the condensing pressure Pc, in accordance with the timing of calculating the actual degree of refrigerant supercooling, and calculates the target refrigerant supercooling. The target refrigerant subcooling degree is selected with reference to the degree table 200.

そして、制御手段60は、選択した目標冷媒過冷却度から実冷媒過冷却度を減じた過冷却度差を用いて、膨張弁4の開度調整を行う。具体的には、実冷媒過冷却度が目標冷媒過冷却度より小さい値の場合は、求めた過冷却度差の値に応じて膨張弁4の開度を小さくする。これにより、水冷媒熱交換器3において水と熱交換を行う冷媒の流量が減少して冷媒の蒸発が促進されるので、実冷媒過冷却度の値が上昇して目標冷媒過冷却度に近づく。一方、実冷媒過冷却度が目標冷媒過冷却度より大きい値の場合は、求めた過冷却度差の値に応じて膨張弁4の開度を大きくする。これにより、水冷媒熱交換器3において水と熱交換を行う冷媒の流量が増加して冷媒の蒸発が抑制されるので、実冷媒過冷却度の値が低下して目標冷媒過冷却度に近づく。 Then, the control means 60 adjusts the opening degree of the expansion valve 4 using the subcooling degree difference obtained by subtracting the actual refrigerant subcooling degree from the selected target refrigerant subcooling degree. Specifically, when the actual degree of refrigerant subcooling is smaller than the target degree of refrigerant subcooling, the opening degree of the expansion valve 4 is reduced in accordance with the value of the calculated degree of subcooling difference. As a result, the flow rate of the refrigerant that exchanges heat with water in the water-refrigerant heat exchanger 3 is reduced and evaporation of the refrigerant is promoted, so that the value of the actual degree of refrigerant subcooling increases and approaches the target degree of refrigerant subcooling. . On the other hand, when the actual refrigerant subcooling degree is larger than the target refrigerant subcooling degree, the opening degree of the expansion valve 4 is increased according to the value of the obtained subcooling degree difference. As a result, the flow rate of the refrigerant that exchanges heat with water in the water-refrigerant heat exchanger 3 increases and evaporation of the refrigerant is suppressed, so that the actual refrigerant subcooling degree decreases and approaches the target refrigerant subcooling degree. .

<目標冷媒過冷却度の補正について>
上述したように、実冷媒過冷却度が目標冷媒過冷却度より小さい値の場合、目標冷媒過冷却度から実冷媒過冷却度を減じた過冷却度差を小さくするために、膨張弁4の開度を小さくして実冷媒過冷却度を上昇させて目標冷媒過冷却度に近づけていく。このとき、冷媒回路10において、水冷媒熱交換器3を流れる冷媒が水に与える熱量が増加して冷媒出口温度が低くなっていく。一方で、温水回路20においては、水冷媒熱交換器3を流れる水が冷媒から受ける熱量が増加することによって往き温度は上昇する。このとき、室内ユニット40における空調負荷が急激に変化する(例えば、室内ユニット40が設置された部屋の窓が開けられる)ことがない限りは、往き温度の上昇に応じて戻り温度も上昇する。水冷媒熱交換器3では、冷媒が水を加熱するために冷媒出口温度が戻り温度より低い温度となることはないこと、および、冷媒出口温度が低くなっていく一方で戻り温度が上昇することにより、実冷媒過冷却度が目標冷媒過冷却度に近づいていくときは、冷媒出口温度から戻り温度を減じた温度差が小さくなっていく。このように、温度差が小さくなる、つまり、実冷媒過冷却度が目標冷媒過冷却度に近い値となるときは、水冷媒熱交換器3における冷媒と水との熱交換量が増加しており、これに起因してCOP値の高い暖房運転が行えている。
<About correction of target refrigerant subcooling degree>
As described above, when the actual refrigerant subcooling degree is smaller than the target refrigerant subcooling degree, the expansion valve 4 is The opening degree is made smaller to increase the actual degree of refrigerant supercooling and bring it closer to the target degree of refrigerant supercooling. At this time, in the refrigerant circuit 10, the amount of heat given to water by the refrigerant flowing through the water-refrigerant heat exchanger 3 increases, and the refrigerant outlet temperature becomes lower. On the other hand, in the hot water circuit 20, the temperature of the water flowing through the water-refrigerant heat exchanger 3 increases as the amount of heat received from the refrigerant increases. At this time, unless the air conditioning load on the indoor unit 40 changes suddenly (for example, the window of the room in which the indoor unit 40 is installed is opened), the return temperature also rises in accordance with the rise in the outgoing temperature. In the water-refrigerant heat exchanger 3, the refrigerant outlet temperature never becomes lower than the return temperature because the refrigerant heats the water, and the return temperature increases while the refrigerant outlet temperature decreases. Therefore, when the actual refrigerant subcooling degree approaches the target refrigerant subcooling degree, the temperature difference obtained by subtracting the return temperature from the refrigerant outlet temperature becomes smaller. In this way, when the temperature difference becomes small, that is, when the actual refrigerant subcooling degree becomes close to the target refrigerant subcooling degree, the amount of heat exchange between the refrigerant and water in the water-refrigerant heat exchanger 3 increases. Due to this, heating operation with a high COP value can be performed.

しかし、目標冷媒過冷却度テーブル200を定めた場合と比べて、温水回路20に設けられる循環ポンプ30の回転数を変化させることによって、あるいは、ヒートポンプサイクル装置100が設置される場所によって温水回路20の水配管16の長さや内径寸法が異なることにより、温水回路20における水の流量が変化する。温水回路20における水の流量が変化すれば、戻り温度や往き温度が変化する。一般的に、室内ユニット40で発揮される暖房能力は、温水回路20における水の流量と、往き温度と戻り温度との温度差の積に比例する。言い換えれば、室内ユニット40で発揮される暖房能力を一定としたとき、往き温度と戻り温度との温度差は水の流量に反比例し、水の流量が増加すれば往き温度と戻り温度との温度差は小さくなり、水の流量が減少すれば往き温度と戻り温度との温度差は大きくなる。このとき、圧縮機1の回転数が固定されていれば、水の流量が増加して温度差が小さくなるときは往き温度が低下し、水の流量が減少して温度差が大きくなるときは往き温度が上昇する。 However, compared to the case where the target refrigerant subcooling degree table 200 is determined, the number of revolutions of the circulation pump 30 provided in the hot water circuit 20 may be changed, or the hot water circuit 20 may be changed depending on the location where the heat pump cycle device 100 is installed. The flow rate of water in the hot water circuit 20 changes as the length and inner diameter of the water pipes 16 differ. If the flow rate of water in the hot water circuit 20 changes, the return temperature and outgoing temperature will change. Generally, the heating capacity exhibited by the indoor unit 40 is proportional to the product of the flow rate of water in the hot water circuit 20 and the temperature difference between the outflow temperature and the return temperature. In other words, when the heating capacity exerted by the indoor unit 40 is constant, the temperature difference between the sending temperature and the return temperature is inversely proportional to the flow rate of water, and as the water flow rate increases, the temperature difference between the sending temperature and the return temperature increases. The difference becomes smaller, and if the water flow rate decreases, the temperature difference between the outgoing temperature and the return temperature becomes larger. At this time, if the rotation speed of the compressor 1 is fixed, when the water flow rate increases and the temperature difference decreases, the temperature will decrease, and when the water flow rate decreases and the temperature difference increases, the temperature will decrease. Outgoing temperature rises.

以上に説明したように、温水回路20における水の流量の変化に起因して往き温度が変化する。また、ヒートポンプサイクル装置100では、往き温度が室内ユニット40で要求される暖房能力に応じて定められた目標温度となるように、圧縮機1の回転数が制御される。このとき、圧縮機1の回転数と凝縮温度とに基づいて目標冷媒過冷却度テーブル200を参照して目標冷媒過冷却度を決定すれば、温水回路20における水の流量を考慮せずに目標冷媒過冷却度を決定することとなり、実冷媒過冷却度が決定した目標冷媒過冷却度となるように膨張弁4の開度を調整しても、温水回路20における水の流量が変化していることに起因してCOP値を最大化できない恐れがあった。 As explained above, the outgoing temperature changes due to a change in the flow rate of water in the hot water circuit 20. Furthermore, in the heat pump cycle device 100, the rotation speed of the compressor 1 is controlled so that the outflow temperature reaches a target temperature determined according to the heating capacity required by the indoor unit 40. At this time, if the target refrigerant subcooling degree is determined by referring to the target refrigerant subcooling degree table 200 based on the rotation speed and condensing temperature of the compressor 1, the target refrigerant subcooling degree can be determined without considering the water flow rate in the hot water circuit 20. Even if the degree of refrigerant subcooling is determined and the opening degree of the expansion valve 4 is adjusted so that the actual degree of refrigerant subcooling becomes the determined target degree of refrigerant subcooling, the flow rate of water in the hot water circuit 20 will not change. There was a risk that the COP value could not be maximized due to the fact that

そこで、本実施形態のヒートポンプサイクル装置100では、実冷媒過冷却度を目標冷媒過冷却度とするために膨張弁4の開度を調整しているときに、実冷媒過冷却度と目標冷媒過冷却度との差である過冷却度差が所定範囲内の値であり、かつ、冷媒出口温度から戻り温度を減じた温度差が第1所定値より大きい値となっていれば、目標冷媒過冷却度に第2所定値を加えて補正目標冷媒過冷却度を算出する。そして、実冷媒過冷却度を補正目標冷媒過冷却度とするために膨張弁4の開度を調整する。 Therefore, in the heat pump cycle device 100 of the present embodiment, when adjusting the opening degree of the expansion valve 4 in order to make the actual refrigerant subcooling degree the target refrigerant subcooling degree, the actual refrigerant subcooling degree and the target refrigerant supercooling degree are adjusted. If the supercooling degree difference, which is the difference from the cooling degree, is within a predetermined range, and the temperature difference obtained by subtracting the return temperature from the refrigerant outlet temperature is larger than the first predetermined value, the target refrigerant A corrected target refrigerant supercooling degree is calculated by adding a second predetermined value to the cooling degree. Then, the opening degree of the expansion valve 4 is adjusted in order to set the actual degree of refrigerant subcooling to the corrected target degree of refrigerant subcooling.

ここで、所定範囲、第1所定値、および、第2所定値は、それぞれ予め試験などを行って求められて、制御手段60に記憶されている値である。所定範囲、および、第2所定値は、ヒートポンプサイクル装置100が暖房運転を行っているときの動作環境が、目標冷媒過冷却度テーブル200を定めた動作環境である場合に、過冷却度差が所定範囲内の値となっており、かつ、冷媒出口温度から戻り温度を減じた温度差が第1所定値以下の値となっていれば、COP値を最大化できていると見込める値である。なお、一例として、所定範囲は±1degであり、第1所定値は2℃である。 Here, the predetermined range, the first predetermined value, and the second predetermined value are values that have been determined in advance by conducting tests, etc., and are stored in the control means 60. The predetermined range and the second predetermined value are such that when the operating environment when the heat pump cycle device 100 is performing heating operation is the operating environment in which the target refrigerant subcooling degree table 200 is defined, the subcooling degree difference is If the value is within the predetermined range and the temperature difference obtained by subtracting the return temperature from the refrigerant outlet temperature is a value equal to or less than the first predetermined value, it is a value that can be expected to maximize the COP value. . Note that, as an example, the predetermined range is ±1 degree, and the first predetermined value is 2°C.

また、第2所定値は、温水回路20における水の流量が減少したことに起因して、実冷媒過冷却度が選択されている目標冷媒過冷却度となっても冷媒出口温度から戻り温度を減じた温度差が大きい場合、つまり、目標冷媒過冷却度テーブル200を定めた動作環境と異なる場合に、この第2所定値を目標冷媒過冷却度に加えて補正し、実冷媒過冷却度がこの補正目標冷媒過冷却度となるように膨張弁24の開度を調整すれば、COP値を改善して最大化できることが判明している値である。なお、一例として、第2所定値は0.5degである。 In addition, the second predetermined value is set to reduce the return temperature from the refrigerant outlet temperature even if the actual refrigerant subcooling degree reaches the selected target refrigerant subcooling degree due to a decrease in the flow rate of water in the hot water circuit 20. When the reduced temperature difference is large, that is, when the operating environment differs from the one in which the target refrigerant subcooling degree table 200 was determined, this second predetermined value is added to the target refrigerant subcooling degree to correct it, and the actual refrigerant subcooling degree is calculated. This is a value that has been found to be able to improve and maximize the COP value by adjusting the opening degree of the expansion valve 24 so as to reach this corrected target refrigerant subcooling degree. Note that, as an example, the second predetermined value is 0.5 degrees.

このように、目標冷媒過冷却度が補正されて、現在の目標冷媒過冷却度より大きい値である補正目標冷媒過冷却度とされると、この補正目標冷媒過冷却度と実冷媒過冷却度との差である補正過冷却度差が、元の目標冷媒過冷却度の場合の過冷却度差より大きな値となる。そして、この補正過冷却度差が小さくなるように膨張弁4の開度が小さくされることで、水冷媒熱交換器3における冷媒と水との熱交換量が増加するので、実冷媒過冷却度が大きな値となっていき冷媒出口温度が低い温度になっていくとともに、戻り温度が高い温度となって、冷媒出口温度と戻り温度との温度差が小さくなっていく。また、戻り温度の上昇に伴って往き温度も上昇するので、圧縮機1の回転数Rを上昇させる必要がない。これら、冷媒出口温度と戻り温度との温度差が小さくなっていくこと、および、温水回路20における水の流量の変化によって低下した往き温度が膨張弁4の開度調整によって上昇することにより圧縮機1の回転数Rを上昇させる必要がないことによって、ヒートポンプサイクル装置100の暖房運転時のCOP値の悪化を抑制できる。 In this way, when the target degree of refrigerant subcooling is corrected and set as the corrected target degree of refrigerant subcooling, which is a value larger than the current target degree of refrigerant subcooling, the corrected target degree of refrigerant subcooling and the actual degree of refrigerant subcooling are The corrected subcooling degree difference, which is the difference between the two, becomes a value larger than the subcooling degree difference in the case of the original target refrigerant subcooling degree. Then, by reducing the opening degree of the expansion valve 4 so that this corrected subcooling degree difference becomes smaller, the amount of heat exchanged between the refrigerant and water in the water-refrigerant heat exchanger 3 increases, so that the actual refrigerant subcooling is reduced. As the temperature increases, the refrigerant outlet temperature becomes lower, the return temperature becomes higher, and the temperature difference between the refrigerant outlet temperature and the return temperature becomes smaller. Moreover, since the outgoing temperature also rises as the return temperature rises, there is no need to increase the rotation speed R of the compressor 1. The temperature difference between the refrigerant outlet temperature and the return temperature becomes smaller, and the outgoing temperature, which has decreased due to a change in the flow rate of water in the hot water circuit 20, is increased by adjusting the opening degree of the expansion valve 4, so that the compressor Since there is no need to increase the rotation speed R of 1, it is possible to suppress deterioration of the COP value during heating operation of the heat pump cycle device 100.

<膨張弁の開度調整に関わる処理の流れについて>
次に、図3を用いて、ヒートポンプサイクル装置100の暖房運転時の膨張弁の開度調整に関わる処理の流れについて説明する。図3に示すのは、制御手段60が暖房運転時に行う膨張弁の開度調整に関わる処理を示すフローチャートである。図3において、STは処理のステップを表し、これに続く数字はステップの番号を表している。なお、図3では、本発明に関わる処理にのみ言及しており、ヒートポンプサイクル装置100に関わるその他の一般的な制御については、記載と説明を省略する。
<About the process flow related to expansion valve opening adjustment>
Next, with reference to FIG. 3, a process flow related to adjusting the opening degree of the expansion valve during heating operation of the heat pump cycle device 100 will be described. FIG. 3 is a flowchart showing a process related to the adjustment of the opening degree of the expansion valve performed by the control means 60 during heating operation. In FIG. 3, ST represents a processing step, and the number following this represents the step number. Note that FIG. 3 only refers to processes related to the present invention, and descriptions and explanations of other general controls related to the heat pump cycle device 100 are omitted.

また、図3では、前述した凝縮圧力Pcに加えて、実冷媒過冷却度をSCp、目標冷媒過冷却度をSCd、目標冷媒過冷却度SCdと実冷媒過冷却度SCpとの差である過冷却度差をΔSC、目標冷媒過冷却度SCdを補正する際にこの目標冷媒過冷却度SCdに加算する加算冷媒過冷却度(本発明の第2所定値に相当)をSCa、補正冷媒過冷却度をSCdn、補正冷媒過冷却度SCdnと実冷媒過冷却度SCpとの差である補正過冷却度差をΔSCn、冷媒出口温度をTro、戻り温度をTwb、冷媒出口温度Troから戻り温度Twbを減じた温度差をΔTとしている。 In addition to the above-mentioned condensation pressure Pc, in FIG. The cooling degree difference is ΔSC, and the additional refrigerant subcooling degree (corresponding to the second predetermined value of the present invention) to be added to the target refrigerant subcooling degree SCd when correcting the target refrigerant subcooling degree SCd is SCa, and the corrected refrigerant subcooling degree is SCa. degree is SCdn, the corrected subcooling degree difference which is the difference between the corrected refrigerant subcooling degree SCdn and the actual refrigerant subcooling degree SCp is ΔSCn, the refrigerant outlet temperature is Tro, the return temperature is Twb, and the return temperature Twb is from the refrigerant outlet temperature Tro. The reduced temperature difference is defined as ΔT.

ヒートポンプサイクル装置100が暖房運転を開始すると、制御手段60は、膨張弁4の開度を初期開度とする(ST1)。ここで、膨張弁4の初期開度は、予め定められて制御手段60に記憶されている値であり、例えば、膨張弁4のステッピングモータに加えるパルス数で100パルスに相当する開度である。そして、制御手段60は、圧縮機1を予め定められた起動時回転数で起動し、この後は、前述したように往き温度センサ58で検出した往き温度が、室内ユニット40で要求される暖房能力に応じて定められた目標温度となるように、回転数が制御される。 When the heat pump cycle device 100 starts heating operation, the control means 60 sets the opening degree of the expansion valve 4 to the initial opening degree (ST1). Here, the initial opening degree of the expansion valve 4 is a value determined in advance and stored in the control means 60, and is, for example, an opening degree corresponding to 100 pulses applied to the stepping motor of the expansion valve 4. . Then, the control means 60 starts the compressor 1 at a predetermined start-up rotation speed, and thereafter, as described above, the outgoing temperature detected by the outgoing temperature sensor 58 is used for heating required by the indoor unit 40. The rotational speed is controlled to reach a target temperature determined according to the capacity.

次に、制御手段60は、冷媒出口温度Troと戻り温度Twbと凝縮圧力Pcとを取り込む(ST2)。具体的には、制御手段60は、冷媒温度センサ55で検出した冷媒出口温度Troを取り込み、戻り温度センサ59で検出した戻り温度Twbを取り込み、吐出圧力センサ51で検出した吐出圧力を水冷媒熱交換器3における凝縮圧力Pcとして取り込む。制御手段60は、上記各値を定期的(例えば、2分毎)に取り込む。 Next, the control means 60 takes in the refrigerant outlet temperature Tro, the return temperature Twb, and the condensing pressure Pc (ST2). Specifically, the control means 60 takes in the refrigerant outlet temperature Tro detected by the refrigerant temperature sensor 55, takes in the return temperature Twb detected by the return temperature sensor 59, and converts the discharge pressure detected by the discharge pressure sensor 51 into water refrigerant heat. This is taken in as the condensation pressure Pc in the exchanger 3. The control means 60 takes in each of the above values periodically (for example, every two minutes).

次に、制御手段60は、実冷媒過冷却度SCpを算出する(ST3)。具体的には、制御手段60は、ST2で取り込んだ凝縮圧力Pcを用いて水冷媒熱交換器3における凝縮温度を求め、ST2で取り込んだ冷媒出口温度Troを減じて、実冷媒過冷却度SCpを算出する。 Next, the control means 60 calculates the actual refrigerant subcooling degree SCp (ST3). Specifically, the control means 60 calculates the condensation temperature in the water-refrigerant heat exchanger 3 using the condensation pressure Pc taken in ST2, subtracts the refrigerant outlet temperature Tro taken in ST2, and obtains the actual refrigerant subcooling degree SCp. Calculate.

次に、制御手段60は、過冷却度差ΔSCを算出する(ST4)。具体的には、制御手段60は、目標冷媒過冷却度SCdからST3で算出した実冷媒過冷却度SCpを減じて、過冷却度差ΔSCを算出する。なお、目標冷媒過冷却度SCdは、前述したように、制御手段60が図2に示す目標冷媒過冷却度テーブル200を参照し、現在の圧縮機1の回転数RとST2で取り込んだ凝縮圧力Pcとに応じた目標冷媒過冷却度SCdを目標冷媒過冷却度テーブル200から選択する。 Next, the control means 60 calculates the subcooling degree difference ΔSC (ST4). Specifically, the control means 60 subtracts the actual refrigerant subcooling degree SCp calculated in ST3 from the target refrigerant subcooling degree SCd to calculate the subcooling degree difference ΔSC. Note that, as described above, the target refrigerant subcooling degree SCd is determined by the control means 60 referring to the target refrigerant subcooling degree table 200 shown in FIG. A target refrigerant subcooling degree SCd corresponding to Pc is selected from the target refrigerant subcooling degree table 200.

次に、制御手段60は、ST4で算出した過冷却度差ΔSCが1deg(本発明の所定範囲)以内の値であるか否かを判断する(ST5)。過冷却度差ΔSCが1deg以内の値であれば(ST5-Yes)、制御手段60は、温度差ΔTを算出する(ST6)。具体的には、制御手段60は、ST2で取り込んだ冷媒出口温度Troから、同じくST2で取り込んだ戻り温度Twbを減じて、温度差ΔTを算出する。 Next, the control means 60 determines whether the subcooling degree difference ΔSC calculated in ST4 is within 1 degree (a predetermined range of the present invention) (ST5). If the supercooling degree difference ΔSC is within 1 degree (ST5-Yes), the control means 60 calculates the temperature difference ΔT (ST6). Specifically, the control means 60 calculates the temperature difference ΔT by subtracting the return temperature Twb also taken in ST2 from the refrigerant outlet temperature Tro taken in ST2.

次に、制御手段60は、ST6で算出した温度差ΔTが2℃(本発明の第1所定値)より大きい値であるか否かを判断する(ST7)。温度差ΔTが2℃より大きい値であれば(ST7-Yes)、制御手段60は、補正冷媒過冷却度SCdnを算出する(ST8)。具体的には、制御手段60は、ST4で過冷却度差ΔSCを算出する際に選択した目標冷媒過冷却度SCdに記憶している加算冷媒過冷却度Ca(本発明の第2所定値。本実施形態では0.5deg)を加算して、補正冷媒過冷却度SCdnを算出する。 Next, the control means 60 determines whether the temperature difference ΔT calculated in ST6 is a value larger than 2° C. (the first predetermined value of the present invention) (ST7). If the temperature difference ΔT is larger than 2° C. (ST7-Yes), the control means 60 calculates the corrected refrigerant supercooling degree SCdn (ST8). Specifically, the control means 60 controls the additional refrigerant subcooling degree Ca (the second predetermined value of the present invention) stored in the target refrigerant subcooling degree SCd selected when calculating the subcooling degree difference ΔSC in ST4. In this embodiment, 0.5 deg) is added to calculate the corrected refrigerant supercooling degree SCdn.

次に、制御手段60は、補正冷媒過冷却度差ΔSCnを算出する(ST9)。具体的には、制御手段60は、ST8で算出した補正冷媒過冷却度SCdnからST3で算出した実冷媒過冷却度SCpを減じて、補正冷媒過冷却度差ΔSCnを算出する。 Next, the control means 60 calculates the corrected refrigerant subcooling degree difference ΔSCn (ST9). Specifically, the control means 60 calculates the corrected refrigerant subcooling degree difference ΔSCn by subtracting the actual refrigerant subcooling degree SCp calculated in ST3 from the corrected refrigerant subcooling degree SCdn calculated in ST8.

そして、制御手段60は、ST9で算出した補正冷媒過冷却度SCdnに基づいて膨張弁4の開度を調整し(ST10)、ST2に処理を戻す。なお、ST5において、過冷却度差ΔSCが1deg以内の値でない場合(ST5-No)、および、温度差ΔTが2℃大きい値でなければ(ST7-No)、制御手段60は、ST4で算出した過冷却度差ΔSCに基づいて膨張弁4の開度を調整し(ST11)、ST2に処理を戻す。 Then, the control means 60 adjusts the opening degree of the expansion valve 4 based on the corrected refrigerant supercooling degree SCdn calculated in ST9 (ST10), and returns the process to ST2. Note that in ST5, if the subcooling degree difference ΔSC is not a value within 1 degree (ST5-No), and if the temperature difference ΔT is not a value 2°C larger (ST7-No), the control means 60 calculates in ST4. The opening degree of the expansion valve 4 is adjusted based on the subcooling degree difference ΔSC (ST11), and the process returns to ST2.

以上説明したように、本実施形態のヒートプンプサイクル装置100では、暖房運転時に膨張弁4の開度調整を行う際に、目標冷媒過冷却度SCdから実冷媒過冷却度SCpを減じて求める過冷却度差ΔSCの値が第1所定値以内の値であり、かつ、冷媒出口温度Troから戻り温度Twbを減じて求める温度差ΔTの値が第2所定値より大きい値である場合に、加算冷媒過冷却度SCaを用いて目標冷媒過冷却度SCdを補正する。これにより、温水回路20における水の流量が変化したことよって、暖房運転時のCOP値が最大化できなくなった場合に、目標冷媒過冷却度SCdを補正することによってCOP値を最大化できる。 As explained above, in the heat pump cycle device 100 of the present embodiment, when adjusting the opening degree of the expansion valve 4 during heating operation, the actual refrigerant subcooling degree SCp is subtracted from the target refrigerant subcooling degree SCd. When the value of the cooling degree difference ΔSC is within the first predetermined value and the value of the temperature difference ΔT obtained by subtracting the return temperature Twb from the refrigerant outlet temperature Tro is larger than the second predetermined value, the addition is performed. The target refrigerant subcooling degree SCd is corrected using the refrigerant subcooling degree SCa. Thereby, when the COP value during heating operation cannot be maximized due to a change in the flow rate of water in the hot water circuit 20, the COP value can be maximized by correcting the target refrigerant supercooling degree SCd.

1 圧縮機
3 水冷媒熱交換器
4 膨張弁
5 熱源側熱交換器
10 冷媒回路
20 温水回路
30 循環ポンプ
40 室内ユニット
51 吐出圧力センサ
55 冷媒温度センサ
59 戻り温度センサ
100 ヒートポンプサイクル装置
200 目標冷媒過冷却度テーブル
Pd 吐出圧力
SCd 目標冷媒過冷却度
SCp 実冷媒過冷却度
SCdn 補正目標冷媒過冷却度
SCa 加算冷媒過冷却度
ΔSC 過冷却度差
ΔSCn 補正過冷却度差
Tro 冷媒出口温度
Twb 戻り温度
ΔT 温度差
1 Compressor 3 Water refrigerant heat exchanger 4 Expansion valve 5 Heat source side heat exchanger 10 Refrigerant circuit 20 Hot water circuit 30 Circulation pump 40 Indoor unit 51 Discharge pressure sensor 55 Refrigerant temperature sensor 59 Return temperature sensor 100 Heat pump cycle device 200 Target refrigerant flow Cooling degree table Pd Discharge pressure SCd Target refrigerant subcooling degree SCp Actual refrigerant subcooling degree SCdn Corrected target refrigerant subcooling degree SCa Additional refrigerant subcooling degree ΔSC Subcooling degree difference ΔSCn Corrected subcooling degree difference Tro Refrigerant outlet temperature Twb Return temperature ΔT temperature difference

Claims (2)

圧縮機と水冷媒熱交換器と膨張弁と熱源側熱交換器とが順次冷媒配管で接続された冷媒回路と、
前記水冷媒熱交換器と利用側ユニットと循環ポンプとが順次水配管で接続された温水回路と、
前記膨張弁の開度を調整する制御手段と、
前記水冷媒熱交換器から流出する冷媒の温度である冷媒出口温度を検出する冷媒温度センサと、
前記水冷媒熱交換器に流入する水の温度である戻り温度を検出する戻り温度センサと、
前記水冷媒熱交換器が凝縮器として機能する際に、前記水冷媒熱交換器における冷媒の凝縮圧力を検出する凝縮圧力センサと、
を有し、
前記制御手段は、暖房運転を行っているとき、
前記冷媒の凝縮圧力を用いて求めた冷媒の凝縮温度から前記冷媒出口温度を減じて求めた実冷媒過冷却度が、前記凝縮圧力と前記圧縮機の回転数に基づいて定められた目標冷媒過冷却度となるように、前記膨張弁の開度を調整し、
前記目標冷媒過冷却度から前記実冷媒過冷却度を減じて求めた過冷却度差が所定範囲内の値であり、かつ、前記冷媒出口温度から前記戻り温度を減じて求めた温度差が第1所定値より大きい値である場合は、前記目標冷媒過冷却度に第2所定値を加算する、
ことを特徴とするヒートポンプサイクル装置。
a refrigerant circuit in which a compressor, a water refrigerant heat exchanger, an expansion valve, and a heat source side heat exchanger are sequentially connected by refrigerant piping;
a hot water circuit in which the water refrigerant heat exchanger, the user side unit, and the circulation pump are sequentially connected through water piping;
control means for adjusting the opening degree of the expansion valve;
a refrigerant temperature sensor that detects a refrigerant outlet temperature that is the temperature of the refrigerant flowing out of the water-refrigerant heat exchanger;
a return temperature sensor that detects a return temperature that is the temperature of water flowing into the water-refrigerant heat exchanger;
a condensation pressure sensor that detects the condensation pressure of refrigerant in the water-refrigerant heat exchanger when the water-refrigerant heat exchanger functions as a condenser;
has
The control means, when performing heating operation,
The actual refrigerant supercooling degree obtained by subtracting the refrigerant outlet temperature from the refrigerant condensation temperature obtained using the refrigerant condensation pressure is the target refrigerant supercooling degree determined based on the condensation pressure and the rotation speed of the compressor. Adjust the opening degree of the expansion valve so that the degree of cooling is achieved,
The subcooling degree difference obtained by subtracting the actual refrigerant subcooling degree from the target refrigerant subcooling degree is within a predetermined range, and the temperature difference obtained by subtracting the return temperature from the refrigerant outlet temperature is a 1. If the value is larger than a predetermined value, a second predetermined value is added to the target refrigerant supercooling degree;
A heat pump cycle device characterized by:
前記制御手段は、
前記実冷媒過冷却度が、前記目標冷媒過冷却度に第2所定値を加算した値となるように、前記膨張弁の開度を調整する、
ことを特徴とする請求項1に記載のヒートポンプサイクル装置。
The control means includes:
adjusting the opening degree of the expansion valve so that the actual degree of refrigerant subcooling becomes a value obtained by adding a second predetermined value to the target degree of refrigerant subcooling;
The heat pump cycle device according to claim 1, characterized in that:
JP2019063187A 2019-03-28 2019-03-28 heat pump cycle equipment Active JP7379846B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2019063187A JP7379846B2 (en) 2019-03-28 2019-03-28 heat pump cycle equipment

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2019063187A JP7379846B2 (en) 2019-03-28 2019-03-28 heat pump cycle equipment

Publications (2)

Publication Number Publication Date
JP2020165540A JP2020165540A (en) 2020-10-08
JP7379846B2 true JP7379846B2 (en) 2023-11-15

Family

ID=72715938

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2019063187A Active JP7379846B2 (en) 2019-03-28 2019-03-28 heat pump cycle equipment

Country Status (1)

Country Link
JP (1) JP7379846B2 (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114506189A (en) * 2020-11-16 2022-05-17 长城汽车股份有限公司 Air conditioning system, control method and device thereof, storage medium and vehicle
JP7485111B1 (en) 2023-02-02 2024-05-16 株式会社富士通ゼネラル Heat pump equipment

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2011069570A (en) 2009-09-28 2011-04-07 Fujitsu General Ltd Heat pump cycle device
JP2013127332A (en) 2011-12-19 2013-06-27 Panasonic Corp Hydronic heating device
JP2016068687A (en) 2014-09-29 2016-05-09 サンデンホールディングス株式会社 Air conditioning unit for vehicle

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2552555B2 (en) * 1989-11-02 1996-11-13 大阪府 How to operate the heat pump

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2011069570A (en) 2009-09-28 2011-04-07 Fujitsu General Ltd Heat pump cycle device
JP2013127332A (en) 2011-12-19 2013-06-27 Panasonic Corp Hydronic heating device
JP2016068687A (en) 2014-09-29 2016-05-09 サンデンホールディングス株式会社 Air conditioning unit for vehicle

Also Published As

Publication number Publication date
JP2020165540A (en) 2020-10-08

Similar Documents

Publication Publication Date Title
EP2458305B1 (en) Heat pump device
JP5657110B2 (en) Temperature control system and air conditioning system
EP1972871B1 (en) Hot water system
US8104299B2 (en) Air conditioner
JP6134856B2 (en) Heat source equipment
EP2730859A1 (en) Refrigeration cycle device
WO2018110185A1 (en) Refrigerant circuit system and method for controlling refrigerant circuit system
EP2857761B1 (en) Water heater
JP7379846B2 (en) heat pump cycle equipment
JP2018141599A (en) Air conditioning device
EP2685177B1 (en) Heat pump-type water heater
JP6536392B2 (en) Air conditioner
JP6123289B2 (en) Air conditioning system
JP7283172B2 (en) heat pump cycle device
JP3740380B2 (en) Heat pump water heater
JP2019163873A (en) Heat pump cycle device
JP2018159520A (en) Air conditioner
JP4349851B2 (en) Refrigeration cycle equipment
JP6086074B2 (en) Heat pump type hot water heater
US11506435B2 (en) Water regulator
JP2019163874A (en) Heat pump cycle device
JP2011163575A (en) Heat pump type hot water supply device
JP2018132218A (en) Air conditioning device
JP5818601B2 (en) Heat pump heat source machine
JP2020201007A (en) Refrigerant cycle system

Legal Events

Date Code Title Description
A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20220127

A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20221207

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20221213

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20230523

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

Free format text: JAPANESE INTERMEDIATE CODE: A01

Effective date: 20231003

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20231016

R151 Written notification of patent or utility model registration

Ref document number: 7379846

Country of ref document: JP

Free format text: JAPANESE INTERMEDIATE CODE: R151