Background
At present, an air-cooled water chiller is generally adopted as a cold source to provide chilled water for the indoor tail end of air conditioning equipment in a communication machine room, particularly a large-scale data center, so that the indoor environment of the communication machine room is cooled. Because the communication equipment in the communication machine room basically operates uninterruptedly all the year round and has very large heat productivity, the air-cooled water chiller used for the communication machine room generally needs annual refrigeration operation, has large operation energy consumption and low seasonal energy efficiency ratio.
In addition, the air-cooled water chiller still needs to start the compressor to work in cold winter, when the outdoor environment is too low, the problem of insufficient liquid supply caused by too low condensing pressure is easy to occur to the compressor, and the heat load of the communication machine room at the moment is small, the frequent start and stop of the compressor can be caused, so that the condition not only causes high energy consumption, but also can reduce the service life of the compressor. Therefore, the reliability of the air-cooled water chiller has been difficult to solve.
Even if a condensing pressure control system is provided and the condenser is designed to be controlled in multiple stages, when the air-cooled chiller runs at subzero outdoor and ambient temperatures for a long time, there is still a great risk, and this may cause an increase in system cost and an increase in control difficulty.
Application number CN201210205485.9 discloses a closed cooling tower refrigerating system applied to an IDC machine room and a refrigerating method thereof. The system comprises a closed cooling tower, a water-cooling refrigerating unit, a cold water tank, a freezing water pump, a cooling water pump, an IDC machine room end device, an embedded control system, a water-cooling refrigerating unit return water temperature sensor, a closed cooling tower return water temperature sensor and a closed cooling tower air inlet dry-wet ball temperature sensor. The refrigeration method of the patent application is operated under the dry working condition of the closed cooling tower in winter, so that the water-cooled refrigeration unit is prevented from being started, energy is saved, and freezing is prevented; the closed cooling tower operates under a wet working condition in transition seasons, so that the water-cooled refrigerating unit is prevented from being started, and energy is saved; the closed cooling tower operates under a wet working condition at night in summer, so that the water-cooled refrigerating unit is prevented from being started, and energy is saved; starting a water-cooling refrigerating unit in the daytime in summer; the running time of the water-cooling refrigerating unit is delayed by utilizing the energy storage of the cold water tank; and in the water cut-off period, the normal operation of the air conditioning system of the IDC machine room is ensured by utilizing the water storage function of the cold water tank. Such a control method is suitable for areas with mild climate and without water shortage. However, in northern areas, because the lowest temperature is-20 to-30 ℃ at night in winter, and even lower temperature occurs in extreme weather, a water cooling mode is adopted, the cooling tower needs to consider anti-freezing measures, the anti-freezing effect is general and not ideal, so that high-concentration anti-freezing solution needs to be added into circulating water of the cooling tower and pipelines, the investment is increased, and the pipelines and equipment are corroded.
Disclosure of Invention
In view of this, the invention aims to overcome the defects of the prior art and provide the heat pipe natural cooling evaporative type condensation water chiller which is suitable for different seasons and has obvious energy-saving effect. In addition, the invention also provides a control method of the evaporative condensation water chiller based on the heat pipe natural cooling.
In order to solve the technical problem, the invention adopts the following scheme:
a heat pipe natural cooling evaporation type condensation water cooler comprises a mechanical refrigeration system consisting of a compressor, a condenser (preferably an evaporation type condenser), a throttler and an evaporator, and further comprises a secondary circulation system for exchanging heat with the evaporator, wherein the secondary circulation system is provided with a natural cooling system capable of controlling the flow direction of a refrigerant (the refrigerant is also called snow and a refrigerant for transferring heat energy and generating a refrigeration effect) in the secondary circulation system so as to exchange heat with the refrigerant; the throttler of the mechanical refrigeration system is connected with a throttler bypass electromagnetic valve in parallel, and the compressor of the mechanical refrigeration system is connected with a compressor bypass electromagnetic valve in parallel; the mechanical refrigeration system, the secondary circulation system and the natural cooling system are electrically connected with a controller, and the controller controls the operation of each system (the controller controls the operation of each system of the water chiller, namely the operation of each component in each system).
The controller can control whether the refrigerant in the secondary circulation system flows to the natural cooling system, the natural cooling system obtains the cooling capacity of the ambient environment to exchange heat with the refrigerant in the secondary circulation system, the mechanical refrigeration system can be closed in certain seasons (such as winter), and the natural cooling system is independently utilized to obtain the cooling capacity. The compressor stops running, the compressor bypass electromagnetic valve and the throttler bypass electromagnetic valve are opened, and at the moment, the mechanical refrigeration system obtains the cold energy of low-temperature air by the heat pipe circulating operation instead of the compressor operation. Mechanical refrigeration system and natural cooling system move alone respectively, do not influence each other, both can utilize natural cooling system alone and acquire cold volume, also can move mechanical refrigeration system alone and refrigerate, can also synthesize both and mix refrigeration, and the holistic refrigeration efficiency of reinforcing adapts to different seasons demands.
This application adopts high-efficient evaporation formula condensation technique, is showing the efficiency ratio that improves the unit, can be when outdoor ambient temperature is lower, through the cold volume of natural cooling system acquisition low temperature environment, furthest's reduction even stop the compressor completely to reduce unit operation energy consumption, energy-conserving effect is showing. The problems of insufficient liquid supply, frequent starting and stopping of the compressor and the like caused by too low high pressure easily generated by refrigeration of the compressor when the outdoor environment is too low can be avoided, and the operation reliability is high.
The secondary circulation system comprises a secondary circulation liquid inlet pipeline and a secondary circulation liquid outlet pipeline, one end of the secondary circulation liquid inlet pipeline and one end of the secondary circulation liquid outlet pipeline are respectively connected with the evaporator, a power pump is arranged on the secondary circulation liquid inlet pipeline or the secondary circulation liquid outlet pipeline, and the natural cooling system is connected with the secondary circulation liquid inlet pipeline or the secondary circulation liquid outlet pipeline. The secondary circulation system provides chilled water for the indoor tail end of the air conditioning equipment. The refrigerant enters the evaporator from the secondary circulation liquid inlet pipeline, then flows out of the evaporator, and is conveyed to the indoor tail end of the air conditioning equipment through the secondary circulation liquid outlet pipeline (namely, the other end of the secondary circulation liquid inlet pipeline and the other end of the secondary circulation liquid outlet pipeline are connected with the air conditioning tail end equipment, so that circulation is formed).
The natural cooling system comprises a natural cooling coil pipe, a natural cooling liquid inlet pipeline and a natural cooling liquid outlet pipeline, wherein one end of the natural cooling liquid inlet pipeline and one end of the natural cooling liquid outlet pipeline are respectively connected with two ends of the natural cooling coil pipe, the other end of the natural cooling liquid inlet pipeline and the other end of the natural cooling liquid outlet pipeline are connected to the secondary circulation liquid inlet pipeline or the secondary circulation liquid outlet pipeline, and a three-way valve is arranged at the joint of the natural cooling liquid inlet pipeline or the natural cooling liquid outlet pipeline and the secondary circulation liquid inlet pipeline or the secondary circulation liquid outlet pipeline (the sentence is interpreted that the joint of the natural cooling liquid inlet pipeline and the secondary circulation liquid inlet pipeline is provided with the three-way valve, or the joint of the natural cooling liquid inlet pipeline and the secondary circulation liquid outlet pipeline is provided with the three-way valve, or the joint of the natural cooling liquid outlet pipeline and the secondary circulation liquid inlet pipeline is provided with the three-way valve, or the joint of the natural cooling liquid outlet pipeline and the secondary circulation liquid outlet pipeline is provided with the three-way valve). The natural cooling system is adjusted through the three-way valve to change the flow direction of the refrigerant in the secondary circulation system, and when the three-way valve opens the branch connected with the natural cooling system, all the refrigerants flow into the natural cooling coil pipe, and the natural cooling coil pipe performs efficient heat exchange on the refrigerants. The three-way valve is a three-way valve or a switch three-way valve which can be adjusted in proportion, preferably, the proportion adjusting three-way valve is selected, and the three-way valve is electrically connected with the controller.
And a condensing fan is arranged on the condenser, and a cooling fan is arranged on the natural cooling coil. The condensing fan and the cooling fan are speed-regulating fans or constant-speed fans. The setting of condensation fan and cooling blower has further improved the radiating effect, gives mechanical refrigeration system, natural cooling system's refrigeration combination and provides more control mode, adapts to the demand of different temperatures. The condensing fan and the cooling fan are electrically connected with the controller.
A liquid inlet temperature sensor is arranged on a secondary circulation liquid inlet pipeline of the secondary circulation system, and a liquid outlet temperature sensor is arranged on a secondary circulation liquid outlet pipeline of the secondary circulation system; the water chiller also includes an outdoor ambient temperature sensor for detecting an outdoor ambient temperature. The inlet temperature sensor is used for detecting the temperature of the refrigerant entering the evaporator, and the outlet temperature sensor is used for detecting the temperature of the refrigerant coming out of the evaporator. The sensors are electrically connected with the controller, the temperature of the refrigerant is directly detected by the liquid inlet temperature sensor and the liquid outlet temperature sensor, and the temperature is compared with the temperature detected by the outdoor environment temperature sensor, so that the purpose of accurate control is achieved.
And a condensing pressure sensor is arranged on a pipeline of the mechanical refrigerating system. The condensation pressure sensor is electrically connected with the controller. When the mechanical refrigeration system operates, if the condensation pressure is too high, the damage of the refrigeration equipment and the increase of the power consumption can be caused; if the condensing pressure is too low, the liquefying process of the refrigerant and the work of the expansion valve are influenced, so that the mechanical refrigerating system cannot work normally, and the refrigerating capacity is greatly reduced. The controller can control the operation of each system according to the numerical value of the condensation pressure sensor, and the condensation pressure is maintained within a normal range.
A control method of a heat pipe natural cooling evaporation type condensation water chiller comprises the following control logics:
1) When the temperature detected by the outdoor temperature sensor is higher than that detected by the liquid inlet temperature sensor, the bypass connected with the natural cooling coil is closed by the three-way valve, all refrigerants of the secondary circulation system directly enter the evaporator without flowing through the natural cooling coil, the compressor bypass electromagnetic valve is closed, the throttler bypass electromagnetic valve is closed, and the compressor performs loading and unloading control according to the temperature of the liquid inlet temperature sensor or the liquid outlet temperature sensor; the loading and unloading control of the compressor specifically comprises the following steps: and when the temperature detected by the liquid inlet temperature sensor or the liquid outlet temperature sensor is lower than the set value, the compressor is controlled to be in loading operation, and when the temperature detected by the liquid inlet temperature sensor or the liquid outlet temperature sensor is lower than the set value, the compressor is controlled to be in unloading operation.
2) When the temperature detected by the outdoor temperature sensor is lower than the temperature detected by the liquid inlet temperature sensor but higher than the temperature for starting a heat pipe (the heat pipe is that the compressor stops running, the compressor bypass electromagnetic valve and the throttler bypass electromagnetic valve are opened, and at the moment, the mechanical refrigeration system forms heat pipe circulation), the bypass connected with the natural cooling coil is opened by the three-way valve, all refrigerants of the secondary circulation system firstly flow through the natural cooling coil and then enter the evaporator, the cooling fan runs in full load, the compressor bypass electromagnetic valve and the throttler bypass electromagnetic valve are closed, and the compressor carries out loading and unloading control according to the temperature detected by the liquid inlet temperature sensor or the liquid outlet temperature sensor; the loading and unloading control of the compressor specifically comprises the following steps: when the temperature detected by the liquid inlet temperature sensor or the liquid outlet temperature sensor is higher than a set value, the compressor is controlled to operate in a loading mode, and when the temperature detected by the liquid inlet temperature sensor or the liquid outlet temperature sensor is lower than the set value, the compressor is controlled to operate in an unloading mode.
3) When the temperature detected by the outdoor temperature sensor is lower than the temperature of starting the heat pipe but higher than the temperature at which the cooling fan can run according to the minimum air quantity or completely stop running, the bypass connected with the natural cooling coil pipe is opened by the three-way valve, all refrigerants of the secondary circulation system firstly flow through the natural cooling coil pipe and then enter the evaporator, the cooling fan runs in full load, the compressor and the condenser are stopped, the compressor bypass electromagnetic valve and the throttler bypass electromagnetic valve are opened, and the condensing fan carries out loading and unloading control according to the temperature detected by the liquid inlet temperature sensor or the liquid outlet temperature sensor; the loading and unloading control of the condensing fan is specifically as follows: when the temperature detected by the liquid inlet temperature sensor or the liquid outlet temperature sensor is higher than a set value, controlling the condensing fan to perform loading operation; and when the temperature detected by the liquid inlet temperature sensor or the liquid outlet temperature sensor is lower than a set value, controlling the condensation fan to unload and run.
4) When the temperature detected by the outdoor temperature sensor is lower than the temperature of stopping the heat pipe but higher than the temperature of the cooling fan which can operate according to the minimum air quantity or completely stop operating, the bypass connected with the natural cooling coil 6 is opened by the three-way valve, all refrigerants of the secondary circulation system firstly flow through the natural cooling coil and then enter the evaporator, the compressor, the condenser and the condensing fan stop operating, the bypass electromagnetic valve of the compressor and the bypass electromagnetic valve of the throttler are opened, and the cooling fan carries out loading and unloading control according to the temperature detected by the liquid inlet temperature sensor or the liquid outlet temperature sensor; the loading and unloading control of the cooling fan is specifically as follows: when the temperature detected by the liquid inlet temperature sensor or the liquid outlet temperature sensor is higher than a set value, the cooling fan is controlled to operate in a loading mode (the rotating speed is increased in the loading mode); and when the temperature detected by the liquid inlet temperature sensor or the liquid outlet temperature sensor is lower than a set value, controlling the cooling fan to unload and run.
5) When the temperature detected by the outdoor temperature sensor is lower than the temperature at which the cooling fan can operate according to the minimum air volume or completely stop operating, the cooling fan operates according to the minimum air volume or completely stops operating, the compressor, the condenser and the condensing fan stop operating, the compressor bypass electromagnetic valve and the throttler bypass electromagnetic valve are closed, and the three-way valve is adjusted and controlled according to the temperature detected by the liquid inlet temperature sensor or the liquid outlet temperature sensor; the regulation control of the three-way valve is specifically as follows: when the temperature detected by the liquid inlet temperature sensor or the liquid outlet temperature sensor is higher than a set value, the three-way valve is controlled to open a bypass connected with the natural cooling coil; when the temperature detected by the liquid inlet temperature sensor or the liquid outlet temperature sensor is lower than a set value, the three-way valve is controlled to close the bypass connected with the natural cooling coil.
Compared with the prior art, the invention has the following beneficial effects: this application adopts evaporative condenser as condensation radiator, adopts the natural cooling coil pipe as the natural cooling heat exchanger, utilizes the heat pipe principle to realize the cooling of refrigerant side, and evaporative condenser and natural cooling coil pipe use one set of independent fan respectively. This application adopts high-efficient evaporation formula condensation technique, is showing the efficiency ratio that improves the unit, can be when outdoor environment temperature is lower, obtains the cold volume of low temperature environment through natural cooling system, and furthest's reduction stops mechanical refrigeration system completely even to reduce unit operation energy consumption, energy-conserving effect is showing, and can avoid outdoor environment low time compressor refrigeration easy high pressure that appears to hang down the problem such as the confession liquid that leads to is not enough and the compressor frequently opens and stops frequently, operational reliability is high.
Detailed Description
In order to make the technical solutions of the present invention better understood, those skilled in the art will further describe the present invention with reference to the accompanying drawings.
Examples
A heat pipe natural cooling evaporation type condensation water chiller comprises amechanical refrigeration system 100 consisting of acompressor 110, anevaporation type condenser 120, arestrictor 130 and anevaporator 140, wherein theevaporation type condenser 120 is provided with acondensation fan 121, and a pipeline of themechanical refrigeration system 100 is provided with acondensation pressure sensor 150. The system further comprises asecondary circulation system 200 for exchanging heat with theevaporator 140, wherein anatural cooling system 300 capable of controlling the flow direction of water in the secondary circulation system to exchange heat with the water is arranged on thesecondary circulation system 200; thethrottler 130 of the mechanical refrigeration system 1 is connected in parallel with a throttler bypasselectromagnetic valve 131, and thecompressor 110 is connected in parallel with a compressor bypasselectromagnetic valve 111; themechanical refrigeration system 100, thesecondary circulation system 200, and thenatural cooling system 300 are electrically connected to acontroller 400, and thecontroller 400 controls the operation of each system.
Thesecondary circulation system 200 includes a secondary circulationliquid inlet pipeline 210 and a secondary circulationliquid outlet pipeline 220, one end of the secondary circulationliquid inlet pipeline 210 and one end of the secondary circulationliquid outlet pipeline 220 are respectively connected to theevaporator 140, and apower pump 250 is disposed on the secondary circulationliquid outlet pipeline 220. Thenatural cooling system 300 includes anatural cooling coil 330, a natural coolingliquid inlet pipeline 310 and a natural coolingliquid outlet pipeline 320, acooling fan 331 is disposed on thenatural cooling coil 330, one end of the natural coolingliquid inlet pipeline 310 and one end of the natural coolingliquid outlet pipeline 320 are respectively connected to two ends of thenatural cooling coil 330, the other end of the natural coolingliquid inlet pipeline 310 and the other end of the natural cooling liquid outlet pipeline 32 are connected to the secondary circulationliquid inlet pipeline 210, and a three-way valve 340 is disposed at a connection position of the natural coolingliquid outlet pipeline 320 and the secondary circulationliquid inlet pipeline 210.
A liquidinlet temperature sensor 230 is arranged on a secondary circulationliquid inlet pipeline 210 of thesecondary circulation system 200, and a liquidoutlet temperature sensor 240 is arranged on a secondary circulation liquid outlet pipeline 220 (the secondary circulation liquid inlet temperature sensor needs to continuously monitor the temperature of a refrigerant, so that the secondary circulation liquid inlet temperature sensor is arranged on a pipeline between an evaporator and a joint of a natural cooling liquid outlet pipeline and the secondary circulation liquid inlet pipeline, or a pipeline between a joint of the natural cooling liquid inlet pipeline and the secondary circulation liquid inlet pipeline and a tail end air conditioning device); the water chiller also includes an outdoorambient temperature sensor 500 for detecting the outdoor ambient temperature.
The control method of the heat pipe natural cooling evaporation type condensation water cooler comprises the following control logics:
1) When the temperature detected by the outdoor temperature sensor is higher than the temperature detected by the liquid inlet temperature sensor, the three-way valve closes a bypass connected with the natural cooling coil, all refrigerants of the secondary circulation system directly enter the evaporator without flowing through the natural cooling coil, the compressor bypass electromagnetic valve is closed, the throttler bypass electromagnetic valve is closed, and the compressor performs loading and unloading control according to the temperature of the liquid inlet temperature sensor or the liquid outlet temperature sensor;
2) When the temperature detected by the outdoor temperature sensor is lower than the temperature detected by the liquid inlet temperature sensor but higher than the temperature for starting the heat pipe, the bypass connected with the natural cooling coil is opened by the three-way valve, all refrigerants of the secondary circulation system flow through the natural cooling coil firstly and then enter the evaporator, the cooling fan runs in full load, the compressor bypass electromagnetic valve and the throttler bypass electromagnetic valve are closed, and the compressor carries out loading and unloading control according to the temperature detected by the liquid inlet temperature sensor or the liquid outlet temperature sensor;
3) When the temperature detected by the outdoor temperature sensor is lower than the temperature of starting the heat pipe but higher than the temperature at which the cooling fan can run according to the minimum air quantity or completely stop running, the bypass connected with the natural cooling coil is opened by the three-way valve, all refrigerants of the secondary circulation system firstly flow through the natural cooling coil and then enter the evaporator, the cooling fan runs in full load, the compressor and the condenser stop running, the compressor bypass electromagnetic valve and the throttler bypass electromagnetic valve are opened, and the condensing fan carries out loading and unloading control according to the temperature detected by the liquid inlet temperature sensor or the liquid outlet temperature sensor;
4) When the temperature detected by the outdoor temperature sensor is lower than the temperature of stopping the heat pipe but higher than the temperature of the cooling fan which can operate according to the minimum air quantity or completely stop operating, the bypass connected with the natural cooling coil 6 is opened by the three-way valve, all refrigerants of the secondary circulation system firstly flow through the natural cooling coil and then enter the evaporator, the compressor, the condenser and the condensing fan stop operating, the bypass electromagnetic valve of the compressor and the bypass electromagnetic valve of the throttler are opened, and the cooling fan carries out loading and unloading control according to the temperature detected by the liquid inlet temperature sensor or the liquid outlet temperature sensor;
5) When the temperature detected by the outdoor temperature sensor is lower than the temperature at which the cooling fan can operate according to the minimum air volume or completely stop operating, the cooling fan operates according to the minimum air volume or completely stops operating, the compressor, the condenser and the condensing fan stop operating, the compressor bypass electromagnetic valve and the throttler bypass electromagnetic valve are closed, and the three-way valve is adjusted and controlled according to the temperature detected by the liquid inlet temperature sensor or the liquid outlet temperature sensor.
The above embodiments are merely specific implementations of the present invention, and the description thereof is specific and detailed, but not construed as limiting the scope of the present invention. It should be noted that, for a person skilled in the art, several variations and modifications are possible without departing from the inventive concept, and such obvious alternatives fall within the scope of the invention.