KR102325379B1 - Operation Control Method for High Temperature Difference and Low Condenser Water Temperature on Cooling Towers - Google Patents

Abstract

The present invention relates to an operation control system and a method for manufacturing large-temperature differential low-temperature cooling water in a cooling tower, and more specifically to the operation control system and method for manufacturing large-temperature differential low-temperature cooling water in a cooling tower that includes a cooling tower for cooling the cooling water through heat exchange between the cooling water introduced from the refrigerator and outside air, and a server for controlling the cooling tower inflow (LA_in) injected into the cooling tower so that the cooling range (ΔTCR), which is the difference between the cooling tower inlet temperature (TA_in) and the cooling tower outlet temperature (TA_out), can be maintained at the maximum. The operation control method for manufacturing large-temperature differential low-temperature cooling water in a cooling tower comprises an initial setting step; an inlet temperature input step; a cooling fan control step; and a pump control step.

Description

Operation Control Method for High Temperature Difference and Low Condenser Water Temperature on Cooling Towers

The present invention relates to an operation control system and method for manufacturing large-temperature differential low-temperature cooling water in a cooling tower, and more specifically, to a low-temperature cooling water by expanding the temperature difference between a cooling water inlet and an outlet, thereby reducing energy consumption of pumps and refrigerators It relates to an operation control system and method for producing a large-temperature differential low-temperature cooling water of a cooling tower that can do this.

Recently, the power consumption has increased significantly due to the increase in power demand due to the enlargement of the building, the increase of cooling/heating and lighting services to create a pleasant building environment, the expansion of communication and computer facilities according to the informatization promotion, and the expansion of the supply of electric heating devices. In particular, the HVAC system accounts for about 55% of the energy consumption of large buildings, and about 21.7% of them are used for cooling energy. Here, the HVAC system is an abbreviation of Heating, Ventilation, & Air Conditioning, that is, heating, ventilation, and air conditioning, that is, a system used for comfort of an indoor environment by integrating them. Therefore, there is an urgent need to reduce cooling energy, which consumes a lot of energy among HVAC systems of large buildings.

In addition, the ratio of the amount of heat removed by the refrigerator to the energy consumed by the refrigerator is called the efficiency (performance) of the refrigerator (COP: Coefficient of Performance). The efficiency (COP) of a refrigerator is not a fixed value, but changes variably according to various physical quantities related to the operation of the refrigerator (temperature of cold water, temperature of cooling water, flow rate of chilled water, capacity of the refrigerator, etc.) and environmental conditions in which the refrigerator is installed. do. That is, the efficiency of the refrigerator can be changed in a very wide range according to the setting of the control values of the refrigerator such as the set temperature of the cold water and the inlet temperature of the cooling water. Therefore, the use efficiency of the refrigerator varies according to how the control value of the refrigerator is optimized and set, which is a very important factor in reducing the amount of cooling energy used in the building energy.

Related Document 1 relates to a cooling water supply temperature control apparatus and method in a building energy management system. More specifically, the cooling water supply temperature of the refrigerator can be changed based on the real-time monitoring of the refrigerator system and the analyzed statistical data, but the cooling water A separate device is required to control the inlet temperature, and there is a limit in that it is impossible to realize energy consumption reduction through large-temperature differential cooling water.

Accordingly, there is a need for a technology capable of increasing the efficiency of equipment by realizing a large temperature difference in a short time at a low cost by using cooling water without a separate additional device in the cooling tower.

KR 10-2013-0117117

The present invention is a cooling range of difference values of the cooling tower the inlet flow (L _{A_in)} can reduce, and the tower inlet temperature (T _{A_in)} and the cooling tower outlet temperature (T _{A_out)} intended to solve the above problems (ΔT A cooling tower comprising a cooling tower for cooling the cooling water through heat exchange between the cooling water introduced from the refrigerator and the atmosphere so as to maintain the maximum _CR ) and a server for controlling _{the cooling tower inflow flow rate (LA_in) flowing into the cooling tower} An object of the present invention is to obtain an operation control system and method for producing a temperature difference low-temperature cooling water.

In order to achieve the above object, an operation control system for producing a large-temperature differential low-temperature cooling water of a cooling tower of the present invention includes: a cooling tower for cooling the cooling water through heat exchange between cooling water introduced from a refrigerator and external air; _{and controlling the cooling tower inflow rate (LA_in} ) of the cooling water cooled in the cooling tower so that the cooling range (ΔT _CR ), which is the difference between the cooling tower inlet temperature (T _{A_in} ) and the cooling tower outlet temperature (T _{A_out ), can be maintained at a maximum} to provide a server;

In addition, in the operation control system for manufacturing large-temperature differential low-temperature cooling water of the cooling tower of the present invention, the cooling tower is installed on one side to measure the temperature and humidity of the outside air, and adjacent to the inlet for receiving the _{cooling tower inflow (LA_in)} a sensor unit installed to measure the cooling tower inflow temperature (T _{A_in );} a cooling fan controlled on/off from the server and lowering the temperature of the coolant during operation (on); and a pump operating so that _{the cooling tower inflow rate (LA_in} ) of the cooling water whose temperature is lowered from the cooling fan can be adjusted according to the control signal transmitted from the server.

In addition, in order to achieve the above object, in the operation control method for manufacturing large-temperature differential low-temperature cooling water of a cooling tower of the present invention, the initial inflow flow rate (L _start ) of cooling water that can be introduced into the cooling tower from the refrigerator is set by the server, an initial setting step in which the cooling fan and the pump are operated; an inflow temperature input step of receiving, by the server, the cooling tower inflow temperature (T _{A_in} ) measured from the sensor unit in the cooling tower, and fixing the cooling tower inflow temperature (T _{A_in );} a cooling fan control step in which, by the server, the operation of the cooling fan is controlled according to the cooling _{tower inflow temperature (T A_in );} and a pump control step in which the pump is controlled by the server so that the cooling tower inflow rate ( _{LA_in} ) is adjusted according to the cooling tower inflow temperature (T _{A_in ).}

As described above, according to the present invention, by providing a cooling tower for cooling the cooling water through heat exchange between the cooling water introduced from the refrigerator and the atmosphere, and _{a server for controlling the cooling tower inflow rate (LA_in} ) flowing into the cooling tower, the cooling tower inflow The flow rate L _{A_in can be reduced and the cooling range ΔT CR} , which is the difference between the cooling tower inlet temperature T _{A_in} and the cooling tower outlet temperature T _{A_out} , can be maintained at the maximum.

In addition, the present invention can reduce the conveyance power of the pump and improve the efficiency of the refrigerator by realizing a large temperature difference according to a decrease in flow rate without adding a separate device or replacing it with a high-efficiency refrigerator. In addition, as the temperature of the condenser is lowered in the cooling cycle of the entire cooling/heat source system, there is an effect of reducing power consumption and improving the efficiency of the refrigerator.

1 is a block diagram of an operation control system for producing a large-temperature differential low-temperature cooling water of a cooling tower of the present invention.
2 is a view showing the maximum cooling range (ΔT _CR ) and the cooling approach range (ΔT _CA ) according to an embodiment of the present invention.
3 is a view showing a cooling cycle in which the efficiency of the refrigerator according to an embodiment of the present invention is increased.
4 is a flowchart of an operation control method for producing a large-temperature differential low-temperature cooling water of a cooling tower according to the present invention.

The terms used in this specification have been selected as currently widely used general terms as possible while considering the functions in the present invention, which may vary depending on the intention or precedent of a person skilled in the art, the emergence of new technology, and the like. In addition, in a specific case, there is a term arbitrarily selected by the applicant, and in this case, the meaning will be described in detail in the description of the corresponding invention. Therefore, the term used in the present invention should be defined based on the meaning of the term and the overall content of the present invention, rather than the name of a simple term.

Unless defined otherwise, all terms used herein, including technical and scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in a commonly used dictionary should be interpreted as having a meaning consistent with the meaning in the context of the related art, and should not be interpreted in an ideal or excessively formal meaning unless explicitly defined in the present application. does not

Operation control system for manufacturing large temperature difference low-temperature cooling water of cooling tower

In general, in the case of a water-cooled cooling heat source system, it accounts for 70-80% of the total amount of energy used for heating and cooling, so it is several times larger than other components. In general, the cooling tower included in the cooling heat source system maintains a constant temperature of the cooling water and injects it into the refrigerator. Accordingly, there is a problem in that a large temperature difference between the inlet temperature and the outlet temperature of the cooling tower cannot be realized in the prior art, and a separate device must be added to realize the large temperature difference. In order to solve this problem, the present invention provides a separate device based on the research result that 3 to 5% of the total cooling energy can be saved when the outlet temperature of the cooling tower for cooling the cooling water is lowered by 1 ° C than 32 ° C. It is intended to realize the large temperature difference of the cooling tower without adding

In other words, the present invention can solve the conventional problem that the difference between the inlet temperature and the outlet temperature cannot be kept constant or expanded, and realize a large temperature difference between the inlet temperature and the outlet temperature of the cooling water, thereby providing a water-cooled cooling heat source system with considerable efficiency. can do. That is, the larger the cooling range, which is the difference between the inlet temperature and the outlet temperature in the cooling tower, the smaller the flow rate is required for the same amount of heat load. In addition, in terms of initial investment, there is an effect that can reduce the size of the pipe accommodating the cooling water in the cooling heat source system, and the capacity of the pump and cooling tower.

Hereinafter, an embodiment according to the present invention will be described in detail with reference to the accompanying drawings. 1 is a block diagram of an operation control system for producing a large-temperature differential low-temperature cooling water of a cooling tower of the present invention. Referring to FIG. 1 , an operation control system for producing a large-temperature differential low-temperature cooling water of a cooling tower according to the present invention includes a cooling tower 100 , a refrigerator 200 , and a server 300 .

First, the temperature and flow rate of the cooling water flowing into the cooling tower 100 from the refrigerator 200 based on the cooling tower 100 are a cooling tower inflow temperature ( _{TA_in} ) and a cooling tower inflow flow rate ( _{LA_in} ). The cooling tower inlet temperature (T _{A_in} ) may be most preferably about 37 ℃. And the temperature and flow rate of the cooling water flowing out from the cooling tower 100 to the refrigerator 200 are the cooling tower outflow temperature T _{A_out} and the cooling tower outflow flow L _{A_out} . The cooling tower outlet temperature (T _{A_out} ) may be most preferably 32 ℃ or less.

In addition, the temperature and flow rate of the cooling water flowing into the refrigerator 200 from the cooling tower 100 based on the refrigerator 200 are a refrigerator inflow temperature (T _{B_in} ) and a refrigerator inflow flow rate ( _{LB_in} ). The refrigerator inlet temperature (T _{B_in} ) may be most preferably 32 ℃ or less. And the temperature and flow rate of the cooling water flowing out from the refrigerator 200 to the cooling tower 100 are the refrigerator outflow temperature T _{B_out} and the refrigerator outflow flow rate L _{B_out} . The refrigerator outlet temperature (T _{B_out} ) may be most preferably about 37 ℃.

In other words, the cooling tower inlet temperature (T _{A_in} ) and the refrigerator outlet temperature (T _{B_out} ) may be the same within the error range. And the cooling tower outlet temperature (T _{A_out} ) and the refrigerator inlet temperature (T _{B_in} ) may be the same within the error range.

To describe the present invention in more detail, the cooling tower 100 cools the cooling water through heat exchange between the cooling water introduced from the refrigerator 200 and the outside air. And the server 300 is a cooling tower injected into the cooling tower 100 so that the cooling range (ΔT _{CR ), which is the difference between the cooling tower inlet temperature (T A_in} ) and the cooling tower outlet temperature (T _{A_out} ) of the cooling water, can be maintained at the maximum. Controls the inflow flow ( _{LA_in).}

Here, most preferably, a separate communication unit may be provided between the cooling tower 100 and the server 300 to enable bidirectional communication. That is, the measurement information measured from the sensor unit 110 of the cooling tower 100 may be transmitted to the server 300 through each of the communication units, and the cooling tower 100 may be transmitted to the server ( 300 ) may receive a control signal for controlling the cooling fan 120 of the cooling tower 100 .

In addition, a separate communication unit may be provided between the server 300 and the refrigerator 200 to enable bidirectional or unidirectional communication. That is, the server 300 may transmit a control signal for controlling the pump 210 of the refrigerator 200 .

The cooling tower 100 includes a sensor unit 110 and a cooling fan 120 . Meanwhile, the cooling tower 100 may further include an inlet 130 accommodating _{the cooling tower inflow flow L A_in} and an outlet 140 accommodating the _{cooling tower outflow L A_out .}

In addition, the cooling tower 100 may most preferably be an open type that is more sensitive to the influence of temperature and humidity of the outside air. That is, in the cooling tower 100 , the cooling water and the outside air are in direct contact with each other, so that heat exchange accompanying evaporation of the cooling water is performed.

Next, the sensor unit 110 is installed on one side to measure the temperature and humidity of the outside air, and is installed adjacent to the inlet 130 for accommodating the _{cooling tower inflow flow (LA_in ) to measure the cooling tower inflow temperature (TA_in} ). measure That is, the sensor unit 110 may be provided with a plurality of sensors, and may be installed inside and outside from the surface of the cooling tower 100 , and the installation location may be different for each sensor.

In other words, in the sensor unit 110, at least one of a temperature and humidity sensor, a dry bulb thermometer, and a wet bulb thermometer may be installed on one side from the surface of the cooling tower 100, and the temperature and humidity of the outside air may be measured. This is because the temperature of the cooling water may be affected by the temperature and humidity of the external environment, and this is to realize a large temperature difference using the temperature of the outside air.

In addition, the sensor unit 110 may be installed adjacent to the inlet 130 of the cooling tower 100 , and may measure _{the cooling tower inlet temperature T A_in .} Meanwhile, the sensor unit 110 may be installed adjacent to the outlet 140 to measure _{the cooling tower outlet temperature T A_out .}

On the other hand, the server 300 may receive the measured temperature measured from the sensor unit 110, the cooling tower inlet temperature (T _{A_in} ) and the cooling tower outlet temperature (T _{A_out} ) The difference between the cooling range (Cooling) Range) (ΔT _CR ) and the cooling tower outlet temperature (T _{A_out} ) and the wet-bulb temperature (T _{air_wet} ) of the outside air, which is a difference value, a Cooling Approach (ΔT _CA ) can be calculated.

2 is a view showing a cooling range (ΔT _CR ) and a cooling approach range (ΔT _CA ) according to an embodiment of the present invention. Referring to FIG. 2, in general, a cooling range, which is a temperature difference between the inlet and outlet temperatures of the cooling tower, may be determined by the heat load and the circulation flow rate. The cooling approach range, which is the temperature difference between the outlet temperature of the cooling tower and the outside temperature, is a function of the cooling capacity of the cooling tower, and the temperature by heat transfer can be determined through the cooling capacity of the cooling tower and the outside wet-bulb air.

That is, in the present invention, the cooling range (ΔT _CR ) can be maximized by realizing a large temperature difference of the cooling water. Accordingly, the cooling approach range (ΔT _CA ) can be lowered, and the low wet bulb temperature condition of the outside air can be actively utilized. In other words, since cooling water is affected by the outside air wet bulb temperature, in summer when the cooling load is large, cooling water of 32°C can be obtained according to the specifications of the cooling tower for most of the period. It becomes possible to manufacture cooling water at a low temperature lower than ℃. Accordingly, there is a remarkable effect of reducing cooling energy and improving efficiency compared to the conventional cooling system.

Next, the cooling fan 120 is controlled on/off from the server 300, and lowers the temperature of the cooling water during operation (on). That is, when the cooling fan 120 is turned on, the fan rotates by a motor and circulates the outside air introduced from the open portion of the cooling tower 100 . Then, the heat of the cooling water is released, and the external air having a relatively low temperature absorbs heat to perform heat exchange, thereby lowering the temperature of the cooling water. And when the cooling fan 120 is turned off, the motor does not drive and the fan also stops rotating.

Next, in general, a refrigerator is composed of a compressor, a condenser, an evaporator, and an expansion valve, and the compressor is operated with an electric motor to compress the gaseous refrigerant and sends it to the condenser, and then liquefies after cooling using water or air flowing in from the outside of the refrigerator do. And it is a device that lowers the ambient temperature through a refrigeration cycle that includes compression, condensation, expansion, and vaporization.

The present invention may include all of a compressor, a condenser evaporator, and an expansion valve in the same way as a general refrigerator, and the refrigerator 200 may include a pump 210 most preferably. The pump 210 may operate so that _{the cooling tower inflow flow L A_in} may be adjusted according to a control signal transmitted from the server 300 . At this time, the position of the pump 210 is not particularly limited, and may be installed inside or outside.

That is, the pump 210 generates a pressure so that the cooling water can be introduced into the cooling tower 100 in order to cool the cooling water that has absorbed the heat, thereby flowing the cooling water. And the pump 210 may be controlled by the on/off state from the server 300 .

When the pump 210 is in an on state, a control signal may be transmitted from the server 300 , and when the pump 210 operates according to the control signal, the cooling water may flow toward the inlet 130 of the cooling tower 100 . In addition, when the pump 210 is in an off state, a pressure through which the coolant can flow is not generated. That is, although some of the cooling water may be introduced into the cooling tower 100 , most of the cooling water is not introduced.

For example, in adjusting the cooling tower inflow flow ( _{LA_in} ), when the server 300 _{transmits a control signal to reduce the cooling tower inflow (LA_in} ) to the pump 210, the pump 210 is It may operate in a direction in which the pressure applied to the cooling water decreases. On the other hand, when the server 300 _{transmits a control signal to increase the cooling tower inflow flow (LA_in} ) to the pump 210, the pump 210 moves in a direction in which the pressure applied to the cooling water becomes stronger. can work

Meanwhile, the server 300 may control _{the cooling tower inflow flow (LA_in} ) based on the following [Equation 1].

Here, L _{A_in} is the cooling tower inflow rate (kg/h), T _{A_in} is the cooling tower inflow temperature (°C), T _{A_out} is the cooling tower outlet temperature (°C), and q _c is the cooling heat amount (kcal/h) .

That is, since the amount of cooling heat (q _c ) in [Equation 1] is constant, the cooling range (ΔT _CR ) can be maintained at the maximum by reducing the cooling tower inflow flow ( _{LA_in} ), and the pressure of the pump (210) There is also an effect of reducing the amount of energy used to generate .

And FIG. 3 is a view showing a cooling cycle in which the efficiency of the refrigerator 200 according to an embodiment of the present invention is increased. In the present invention, by injecting the cooling water in which the large temperature difference is maintained into the refrigerator 200, as shown in FIG. 3, a decrease in refrigerant pressure occurs due to the large temperature difference cooling water in the cooling cycle, thereby improving the efficiency of COP, which is the performance coefficient of the refrigerator. has the effect of being Here, COP is a ratio between the refrigeration capacity and the consumed compressor work, and the smaller the compression day and the higher the refrigeration effect, the higher the COP efficiency.

Meanwhile, the server 300 may calculate _{the wet-bulb temperature T air_wet} of the outside air using the temperature and humidity values of the outside air measured by the sensor unit 110 in the cooling tower 100 . The wet-bulb temperature (T _{air_wet} ) of the outside air may be a temperature at which the humidity of the ambient air flowing toward the cooling tower 100 is reflected. When the humidity of the ambient air, that is, the outside air is 100%, the wet-bulb temperature (T _{air_wet} ) and the dry-bulb temperature (T _{air_dry} ) are the same, and the lower the humidity of the outside air, the lower the wet-bulb temperature (T _{air_wet} ).

)의 값을 이용하여 상기 외기의 습구온도(T_{air_wet})를 산출할 수 있다.In general, the wet-bulb temperature (T _{air_wet} ) of the outside air can be directly measured using a wet-bulb thermometer, but most buildings do not have this, so the server 300 of the present invention is most preferably the sensor unit 110. Dry bulb temperature (T _{air_dry} ) and relative humidity (

) can be used to calculate the wet-bulb temperature (T _{air_wet ) of the outside air.}

_{For example, to explain, the server 300 preferentially calculates the wet bulb temperature (T air_wet} ) of the outside air by a calculation method through a convergence calculation, using the following [Equation 2], which is Wexler-Hyland's formula, saturated air The partial pressure of water vapor (f _s ) can be calculated.

Here, T _ab is a value obtained by converting the _{dry bulb temperature (T air_dry} ) measured by the sensor unit 110 into an absolute temperature.

)와 상기 포화공기의 수증기분압(f_s)을 하기 [수학식 3]에 대입하여 상기 외기의 수증기분압(f)을 산출할 수 있다.And the server 300 is the relative humidity (

) and the partial pressure of water vapor in the saturated air (f _s ) can be substituted into the following [Equation 3] to calculate the partial pressure of water vapor in the outside air (f).

And the server 300 can calculate the absolute humidity (x) by substituting the water vapor partial pressure (f) into the following [Equation 4].

And the server 300 may calculate the specific enthalpy (h) by substituting the absolute humidity (x) and the dry bulb temperature (T _{air_dry ) into the following [Equation 5].}

)를 산출할 수 있다. 이때, 상기 노점온도(

)는 일정한 압력 하에서 온도를 내려서 외기가 포화되는 순간의 온도이고, 오차범위는

0.1℃ 미만일 수 있다.And the server 300 first calculates the Y value by substituting the water vapor partial pressure (f) of the outside air into the following [Equation 6], and then the dew point temperature (

) can be calculated. At this time, the dew point temperature (

) is the temperature at the moment when the outside air is saturated by lowering the temperature under a constant pressure, and the error range is

It may be less than 0.1°C.

)에 대한 비엔탈피(h’)를 하기 [수학식 7]에 대입하여 상기 외기의 습구온도(T_{air_wet})에 대한 비엔탈피(hc’)를 산출할 수 있다.Next, the server 300 determines the specific _{enthalpy (h) for the dry bulb temperature (T air_dry} ) of the outside air and the dew point temperature (

) by substituting the specific enthalpy (h') for [Equation 7] below to calculate the specific enthalpy (hc') with respect to _{the wet bulb temperature (T air_wet ) of the outside air.}

)에 대한 비엔탈피 및 절대습도이고, hc’는 상기 센서부(110)에 포함될 수 있는 건구온도계의 표면에 있는 물의 비엔탈피이다. 즉, hc’의 상기 외기의 습구온도(T_{air_wet})와 근사값일 수 있다. Here, h and x are the specific enthalpy and absolute humidity with respect to _{the dry-bulb temperature (T air_dry ) of the outside air.} h' and x' are the dew point temperature (

) and absolute humidity, and hc' is the specific enthalpy of water on the surface of the dry bulb thermometer that may be included in the sensor unit 110 . That is, hc' may be an approximate value of the wet-bulb temperature (T _{air_wet ) of the outside air.}

)라고 정의한다면 (t₁>t₂) t₁과 t₂ 범위 내에 상기 외기의 습구온도(T_{air_wet})가 있다고 가정하고, 이 범위를 점점 줄여나가며 최종적으로 상기 외기의 습구온도(T_{air_wet})를 산출할 수 있다.In addition, the server 300 may calculate the _{wet-bulb temperature T air_wet} , which is an approximate value of hc', using the following [Equation 8] that is modified from [Equation 7] based on a numerical solution. In this case, t ₁ is the dry-bulb temperature (T _{air_dry} ) of the outside air, and t ₂ is the dew point temperature (

), it _{is assumed that there is a wet-bulb temperature (T air_wet} ) of the outside air within the ranges of t ₁ and t _{2 (t 1} >t ₂ ), and the range is gradually reduced to finally obtain the wet-bulb temperature (T _{air_wet} ) of the outside air. can be calculated.

)에 대한 비엔탈피 및 절대습도이고, T_{air_wet}는 상기 외기의 습구온도이다. Here, h and x are the specific enthalpy and absolute humidity with respect to _{the dry-bulb temperature (T air_dry ) of the outside air.} h' and x' are the dew point temperature (

) and absolute humidity, and T _{air_wet} is the wet-bulb temperature of the outside air.

First, when the air is saturated is equal to the dry bulb temperature (T _{air_dry)} of the outside air wet bulb temperature (T _{air_wet)} of the atmosphere, at this time has the calculated value can be described as err err _1. And err, which is a result of substituting the average temperature T _{w , which is the average value of t 1} and t ₂ in Equation 8, into the wet bulb temperature T _{air_wet} of the outside air, may be referred to _{as err w .}

Here, _{if the signs of err 1} and err _w do not match, the wet bulb temperature (T _{air_wet} ) of _{the outside air may be within the range of t w} <T _{air_wet} < t ₁ , and the average temperature (t _w ) may be substituted with _{t 2 .} can On the other hand, _{if the signs of err 1} and err _w match, the wet bulb temperature (T _{air_wet} ) of _{the outside air may be within the range of t 2} <T _{air_wet} < t _w , and the average temperature (t _w ) may be substituted with _{t 1 .} can And most preferably, the server 300 may repeat the above calculation within 100 times until ^{the value of err becomes 10 −5 or less according to [Equation 8].} _{That is, the average temperature t w} corresponding to the case where the value of the err becomes 10 ^-5 or less may be finally output as the wet-bulb temperature T _{air_wet of the outside air.}

_{Accordingly, the server 300 can calculate the wet-bulb temperature (T air_wet} ) of the outside air without adding a separate device in most buildings equipped with a dry-bulb thermometer through the method of the embodiment, and measure the temperature and humidity of the external environment. There is a remarkable effect of maximizing the efficiency of the cooling heat source system by fully reflecting and adjusting the cooling tower inflow flow ( _{LA_in ) to realize a large temperature difference low-temperature cooling water.}

Operation control method for manufacturing large temperature difference low-temperature cooling water of cooling tower

Hereinafter, an embodiment according to the present invention will be described in detail with reference to the accompanying drawings. 4 is a flowchart of an operation control method for producing a large-temperature differential low-temperature cooling water of a cooling tower according to the present invention.

4, the operation control method for producing a large-temperature differential low-temperature cooling water of the cooling tower of the present invention includes an initial setting step (S100), an input temperature input step (S200), a cooling fan control step (S300), and a pump control step (S400) includes

_{More specifically, in the initial setting step (S100), the initial inflow flow rate (L start} ) of the cooling water that can be introduced into the cooling tower 100 from the refrigerator 200 is set by the server 300 , and the cooling fan 120 ) and the pump 210 are operated.

Here, in the initial setting step (S100), the number of the refrigerators 200 in operation is multiplied by the total flow rate of cooling water that each refrigerator 200 can accommodate by the server 300, and the initial inflow flow rate of the cooling water ( L _start ) can be calculated. This is to preferentially check the flow rate that can be introduced into the entire cooling tower 100 .

In addition, the cooling fan 120 and the pump 210 may be turned on and operated in order to return to the refrigerator 200 after cooling the coolant whose temperature has risen from the refrigerator 200 .

_{Next, in the inputting of the inlet temperature (S200), the cooling tower inlet temperature T A_in} measured from the sensor unit 110 in the cooling tower 100 is received by the server 300, and the cooling tower inlet temperature (T _{A_in} ) is fixed.

If the cooling tower inlet temperature (T _{A_in} ) is not fixed, the inflow temperature ( _{TA_in} ) of the cooling water changes according to the cooling tower outlet temperature ( _{TA_out} ), so that the temperature difference cannot be continuously realized, and the cooling tower inflow rate ( _{LA_in} ) is also Since it is not adjusted, it is very important in the present invention to fix _{the cooling tower inlet temperature (T A_in ).}

Most preferably, in the inlet temperature input step (S200), noise is considered and the temperature at which the cooling tower 100 is stabilized after a few minutes has passed is the cooling tower inlet temperature ( _{TA_in} ). can be fixed by

℃를 모두 곱산한 값이므로, 상기 냉각탑유입온도(T_{A_in})가 상기 유입온도 입력단계(S200)로부터 고정될 경우 상기 외기의 습구온도(T_{air_wet})의 영향을 받은 상기 냉각탑유출온도(T_{A_out})가 상당히 낮춰짐에 따라 상기 냉각수의 대온도차 실현이 가능하도록 한다. In other words, the amount of heat treated by the cooling tower 100 is the difference between the cooling tower inlet temperature ( _{TA_in} ) and the cooling tower outlet temperature ( _{TA_out} ), the cooling tower inflow rate ( _{LA_in} ), the specific heat of 4.185J/g

Since it is a value obtained by multiplying all ℃, when the cooling tower inlet temperature (T _{A_in} ) is fixed from the inlet temperature input step (S200), the cooling tower outlet temperature (T _{A_out} ) _{affected by the wet bulb temperature (T air_wet ) of the outside air} is significantly lowered, making it possible to realize a large temperature difference of the cooling water.

)의 값이 이용되어 상기 외기의 습구온도(T_{air_wet})가 산출될 수 있다.On the other hand, the input temperature input step (S200) is a wet-bulb temperature calculation step (S210) in which the wet- _{bulb temperature (T air_wet} ) of the outside air is calculated using the temperature and humidity of the outside air measured from the sensor unit 110 in the cooling tower 100 ( S210 ). ) may be included. This is the dry-bulb temperature (T _{air_dry} ) and the relative humidity (

) may be used to calculate the wet-bulb temperature (T _{air_wet ) of the outside air.}

Next, in the cooling fan control step S300 , the operation of the cooling fan 120 is controlled by _{the server 300 according to the cooling tower inflow temperature T A_in .}

At this time, in the cooling fan control step (S300), if the cooling tower inflow temperature (T _{A_in} ) is lower than the preset refrigeration period lower limit temperature (T _{B_min} ), the cooling fan 120 operating from the initial setting step (S100) This can be stopped. On the other hand, if the cooling tower inflow temperature T _{A_in} is higher than the preset refrigeration lower limit temperature T _{B_min} , the cooling tower inflow temperature T _{A_in} is continuously operated (on) state in order to decrease the cooling tower inflow temperature T A_in . may be maintained, and the pump control step (S400) may proceed.

Here, in the cooling tower outlet temperature (T _{A_out} ), that is, the refrigerator inlet temperature (T _{B_in} ) flowing into the condenser portion of the refrigerator 200, the cooling cycle of the refrigerator 200 as shown in FIG. 3 is stably maintained. In order to do this, in the refrigerator 200, the refrigerator lower limit temperature T _{B_min} may be preset. This may be different for each manufacturer of the refrigerator 200 .

That is, when the _{cooling fan 120 is operated despite the cooling tower inflow temperature (T A_in ) being less than the freezing period} lower limit temperature (T B_min ), the temperature of the cooling water passing through the cooling tower 100 is lowered. This is because the cooling tower outlet temperature (T _{A_out} ) and the refrigerator inlet temperature (T _{B_in} ) are lower than the refrigerator lower limit temperature (T _{B_min} ), so that there is a problem that the cooling cycle cannot be stably maintained.

Next, in the pump control step ( S400 ), the pump 210 is controlled by the server 300 so that the cooling tower inflow rate L _{A_in is adjusted according to the cooling tower inflow temperature T A_in .}

That is, in the pump control step (S400), when the cooling tower inflow temperature (T _{A_in ) is higher than the wet bulb temperature (T air_wet} ) of the outside air calculated from the server 300 , the cooling tower inflow flow rate ( _{LA_in} ) is reduced. The operation of the pump 210 may be controlled.

Meanwhile, in the pump control step (S400) _{, a value obtained by adding} an extra value (α) to the wet bulb temperature (T air_wet ) of the outside air and the cooling tower inlet temperature (T _{A_in} ) may be compared according to site conditions. The extra value (α) may most preferably be 2°C.

The extra value α is considered in order to operate conservatively for stability and robustness of the system from a control point of view. That is, in theory, the temperature of the cooling water _{may be lowered to the wet-bulb temperature (T air_wet} ) of the outside air, but in practice this may not be the case. If so, the pump control step (S400) of the present invention is an error value because it becomes an uneconomical system because it is necessary to add the capacity of the cooling tower 200 to lower it than the predetermined temperature or it may be designed excessively. We try to solve this problem by considering α) in advance.

In addition, in the pump control step (S400), if the cooling tower inflow flow rate ( _{LA_in ), which is reduced as the pump 210 is controlled, is not equal to the pre} -stored cooling tower lower limit flow rate (LA_min), it regresses and returns to the cooling tower inflow temperature (T _{A_in} ) may be compared with the sum of the wet-bulb temperature (T _{air_wet} ) of the outside air or the wet-bulb temperature (T _{air_wet} ) of the outside air and an extra value (α). Here, the cooling tower lower limit flow rate ( _{LA_min} ) is a minimum flow rate in consideration of motor heat within the pump 210, a minimum flow rate of the refrigerator 200 specification, and a minimum flow rate of the cooling tower 100. A lower limit may be determined.

As a result of the comparison again, if the cooling tower inflow temperature (T _{A_in} ) is higher than the wet-bulb temperature (T _{air_wet} ) of the outside air or the sum of the wet-bulb temperature (T _{air_wet} ) and the extra value (α) of the outside air, the cooling tower inflow flow rate ( L _{A_in} ) may be decreased again. And not the same as the reduction the cooling tower the inlet flow (L _{A_in)} is pre-stored the cooling tower lower flow rate (L _{A_min)} wet bulb temperature of the outside air (T _{air_wet)} or wet-bulb temperature of the outside air (T _{air_wet)} and replacement value (α ) can be compared again with the sum of the values, and this process can be repeated.

On the other hand, in the pump control step (S400), when the cooling tower inflow flow rate ( _{LA_in} ), which is reduced as the pump 210 is controlled, is equal to the stored cooling tower lower limit flow rate ( _{LA_min} ), the reduced cooling tower inflow flow rate ( L _{A_in} ) may be maintained and the pump control step (S400) may be terminated.

Accordingly, in the present invention, the cooling tower inflow rate ( _{LA_in} ) can be reduced, and the cooling range (ΔT _CR ), which is the difference between the cooling tower inflow temperature (T _{A_in} ) and the outflow temperature (T _{A_out ) of the cooling water, is the maximum} can be maintained as In addition, in the present invention, as the cooling water maintaining a large temperature difference is injected into the refrigerator 200, the temperature of the condenser that can be included in the refrigerator 200 in the cooling cycle is lowered and the power consumption of the compressor is reduced, so that the refrigerator 200. It has the effect of increasing the overall efficiency of

As described above, although the embodiments have been described with reference to the limited embodiments and drawings, various modifications and variations are possible for those skilled in the art from the above description. For example, the procedures described may be performed in an order different from the method described, and/or components such as systems, structures, devices, circuits, etc. Substituted or substituted for elements or equivalents may achieve appropriate results.

Therefore, other implementations, other embodiments, and equivalents to the claims also fall within the scope of the following claims.

100.. cooling tower
110. Sensor part
120.. cooling fan
130.. Inlet
140.. Outlet
200.. Freezer
210. Pump
300.. Server

Claims (6)

delete _{Initial setting step in which the initial inflow flow rate (L start} ) of the cooling water that can be introduced into the cooling tower 100 from the refrigerator 200 is set by the server 300 , and the cooling fan 120 and the pump 210 are operated ;
an input step of receiving, by the server 300, the cooling tower inflow temperature T _{A_in} measured from the sensor unit 110 in the cooling tower 100, and fixing the cooling tower inflow temperature T _{A_in} ;
a cooling fan control step in which the operation of the cooling fan 120 is controlled by the server 300 according to the cooling tower inflow temperature T _{A_in ;} and
A pump control step in which the pump 210 is controlled so that the cooling tower inflow rate ( _{LA_in ) is adjusted according to the cooling tower inflow temperature (T A_in} ) by the server (300);
The input temperature input step is,
By being fixed to the cooling tower inlet temperature of cooling water (T _{A_in),} the cooling tower of the cooling water inlet temperature (T _{A_in)} the cooling tower outlet temperature (T _{A_out)} without fluctuating the cooling tower inlet temperature in accordance with (T _{A_in)} and the cooling tower outlet temperature The maximum cooling range (ΔT _CR ), which is the difference value of (T _{A_out ), gradually increases,}
The input temperature input step is,
The dry-bulb temperature (T _{air_dry} ) and the relative humidity (

) is used to _{calculate the wet-bulb temperature (T air_wet} ) of the outside air, including a wet-bulb temperature calculation step;
The wet-bulb temperature calculation step is,
_{The following [Equation 2] is used so that the wet bulb temperature (T air_wet} ) of the outside air can be calculated through the convergence calculation to calculate the partial pressure of water vapor in the saturated air (f _s ),
[Equation 2]

Here, T _ab is a value obtained by converting the _{dry bulb temperature (T air_dry} ) measured by the sensor unit 110 into an absolute temperature,
Relative humidity measured from the sensor unit 110 (

) and the partial pressure of water vapor in the saturated air (f _s ) are substituted into the following [Equation 3] to calculate the partial pressure of water vapor in the outside air (f),
[Equation 3]

The water vapor partial pressure (f) of the outside air is substituted in [Equation 4] to calculate the absolute humidity (x),
[Equation 4]

The absolute humidity (x) and the dry-bulb temperature (T _{air_dry} ) of the outside air are substituted into the following [Equation 5] to calculate the specific enthalpy (h),
[Equation 5]

Here, θ is the dry bulb temperature of the outside air (T _{air_dry} ),
The water vapor partial pressure (f) of the outdoor air is substituted into the following [Equation 6] to first calculate the Y value, and then, as the temperature is lowered under a constant pressure, the dew point temperature (θ _d ), which is the temperature at the moment when the outdoor air is saturated, is calculated and ,
[Equation 6]

The specific enthalpy (h) with respect to the dry-bulb temperature (T _{air_dry ) of the outside air and the specific enthalpy (h') with respect to the dew point temperature (θ d} ) are substituted into the following [Equation 7] to obtain the wet-bulb temperature (T _{air_wet) of the outside air.} ) for the specific enthalpy (hc') is calculated,
[Equation 7]

Here, h and x are the specific _{enthalpy and absolute humidity with respect to the dry bulb temperature (T air_dry} ) of the outside air, and h' and x' are the specific enthalpy and absolute humidity with respect to _{the dew point temperature (θ d ),}
The [Equation 7] is repeatedly calculated until the err value, which is the result value of the following [Equation 8] modified based on the numerical solution, becomes 10 ^-5 or less, and the err value becomes 10 ^-5 or less. The average temperature (t _w ) at the time is output as the wet-bulb temperature (T _{air_wet ) of the outside air,}
[Equation 8]

The pump control step is
When the cooling tower inflow temperature (T _{A_in} ) is higher than the wet bulb temperature (T _{air_wet} ) of the outside air, the operation of the pump 210 is controlled to reduce the cooling tower inflow flow ( _{LA_in ), whereby the maximum cooling range (ΔT CR} ) _{As ΔT CA increases} , the cooling access range (ΔT CA ), which is the difference between the cooling tower outlet temperature (T _{A_out} ) and the wet-bulb temperature (T _{air_wet} ) of the outside air, decreases, the efficiency of the cooling tower 100 is improved, characterized in that An operation control method for producing low-temperature cooling water with a large temperature difference in a cooling tower. 3. The method of claim 2,
The cooling fan control step,
When the cooling tower inflow temperature (T _{A_in} ) is lower than the preset refrigeration period lower limit temperature (T _{B_min} ), the cooling fan 120 operating from the initial setting step is stopped. for driving control methods. delete delete 3. The method of claim 2,
The pump control step is
If the cooling tower inflow flow rate ( _{LA_in ), which is reduced as the pump 210 is controlled, is not equal to the pre} -stored cooling tower lower limit flow rate (LA_min), the cooling tower inflow temperature ( _{TA_in} ) is the wet bulb temperature (T _{air_wet) of the outside air.} ) is compared again with
_{When the cooling tower inflow rate (LA_in} ), which is reduced as the pump 210 is controlled, is equal to the previously stored cooling tower lower limit flow rate ( _{LA_min} ), the reduced cooling tower inflow rate ( _{LA_in} ) is maintained, characterized in that Operation control method for manufacturing large temperature difference low-temperature cooling water of cooling tower.

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