阅读说明：本技术 冷水机组、其进出水压调节方法及空调系统 (Water chilling unit, inlet and outlet water pressure adjusting method thereof and air conditioning system ) 是由 胡江 沈丽凤 钱沛 周葆林 于 2019-08-30 设计创作，主要内容包括：本发明公开了一种冷水机组、其进出水压调节方法及空调系统,其中冷水机组进出水压调节方法包括以下步骤：步骤1.实时检测每台冷却塔水泵的出水量,将该出水量与主控板输出的出水量进行比较,并根据比较结果调整每台冷却塔水泵的出水量；步骤2.将各冷却塔平衡模块发出的输出信号进行比较,并将比较结果反馈给主控板,主控板对各冷却塔的出水量进行调节,实现各冷却塔之间的均衡。本发明可以实现多个冷却塔的进出水水压平衡调节,避免了机组工作时水压异常引起的安全隐患。(the invention discloses a water chilling unit, an inlet and outlet water pressure adjusting method thereof and an air conditioning system, wherein the inlet and outlet water pressure adjusting method of the water chilling unit comprises the following steps: step 1, detecting the water output of each cooling tower water pump in real time, comparing the water output with the water output by a main control board, and adjusting the water output of each cooling tower water pump according to a comparison result; and 2, comparing output signals sent by the balance modules of the cooling towers, feeding the comparison result back to the main control board, and adjusting the water yield of the cooling towers by the main control board to realize the balance among the cooling towers. The invention can realize the balance adjustment of the water pressure of inlet and outlet water of a plurality of cooling towers, and avoids the potential safety hazard caused by abnormal water pressure when the unit works.)

1. the water chilling unit comprises at least two cooling towers which are used in parallel, and is characterized in that each cooling tower comprises a water pressure prepositive adjusting circuit, a water pressure balance adjusting circuit and a main control board, wherein the main control board controls the water pressure prepositive adjusting circuit to realize the real-time adjustment of the water yield of a single cooling tower, and controls the water pressure balance adjusting circuit to realize the water yield balance adjustment among the multiple cooling towers.

2. The water chilling unit of claim 1, wherein the water pressure pre-conditioning circuit includes a water pressure detection module, a water pressure control module, and a first comparison module for comparing the control signal output by the water pressure control module with the water pressure detection signal output by the water pressure detection module and adjusting the output water volume of the cooling tower water pump.

3. The water chilling unit according to claim 2, wherein the first comparison module includes a subtractor and an adder, the input signals of the subtractor are the control signal output by the water pressure control module and the water pressure detection signal output by the water pressure detection module, the output signal of the subtractor and the control signal output by the water pressure control module are used as the input end of the adder, and the output end of the adder is used for controlling the adjustment of the water pump.

4. The chiller according to claim 3 wherein said subtractor comprises: the negative input end of the operational amplifier U9 receives the water pressure detection signal output by the water pressure detection module through a resistor, the positive input end of the operational amplifier U9 receives the control signal output by the water pressure control module through a resistor, the positive input end of the operational amplifier U9 is grounded through a resistor, the output end of the operational amplifier U9 is connected with the adder, and the output end of the operational amplifier U9 is connected with the negative input end of the operational amplifier U9 through a resistor.

5. the chiller according to claim 3 wherein said summer comprises: the positive input end of the operational amplifier U3 is connected with the output end of the subtracter through a resistor, the positive input end of the operational amplifier U3 is further connected with the output end of the water pressure control module through a resistor, the negative input end of the operational amplifier U3 is grounded through a resistor, and the output end of the operational amplifier U3 outputs a water pump control signal.

6. the water chilling unit according to claim 1, wherein the water pressure balance adjustment circuit includes a balancing module for receiving a detection signal from the water pressure detection module of each cooling tower and a water pressure control signal from the main control board; and the second comparison module is used for receiving and comparing output signals sent by the balance modules of the cooling towers and feeding back comparison results to the main control board, and the main control board adjusts water yield output control signals according to the comparison results to realize water yield balance among the cooling towers.

7. The chiller according to claim 6 wherein said balancing module comprises a differential amplifier comprising: the operational amplifier U1, the operational amplifier U2 and the operational amplifier U4, the positive input end of the operational amplifier U2 connects the water pressure detection signal sent out by the water pressure detection module, the negative input end of the operational amplifier U2 connects to the negative input end of the operational amplifier U1 through a resistance, the output end of the operational amplifier U2 connects to the positive input end of the operational amplifier U4 through a resistance, the output end of the operational amplifier U2 connects to its negative input end through a resistance; the positive input end of the operational amplifier U1 is connected with a water pressure control signal sent by the main control board, the output end of the operational amplifier U1 is connected with the negative input end of the operational amplifier U4 through a resistor, and the output end of the operational amplifier U1 is also connected with the negative input end of the operational amplifier U1 through a resistor; the positive input terminal of the operational amplifier U4 is further grounded through a resistor, the output terminal of the operational amplifier U4 is connected to the input terminal of the second comparing module through a resistor, and the output terminal of the operational amplifier U4 is further connected to the negative input terminal thereof through a resistor.

8. The chiller according to claim 6 wherein said second comparison module comprises: the negative input end of the operational amplifier U8 is connected to the output end of one balancing module through a resistor, the positive input end of the operational amplifier U8 is connected to the output end of the other balancing module through a resistor, the positive input end of the operational amplifier U8 is grounded through a resistor, the output end of the operational amplifier U8 feeds back the comparison result to the main control board, and the output end of the operational amplifier U8 is connected to the negative input end of the operational amplifier U8 through a resistor.

9. A method for adjusting the water pressure of a water chilling unit in and out is characterized by comprising the following steps:

Step 1, detecting the water output of each cooling tower water pump in real time, comparing the water output with the water output by a main control board, and adjusting the water output of each cooling tower water pump according to a comparison result;

And 2, comparing output signals sent by the balance modules of the cooling towers, feeding the comparison result back to the main control board, and adjusting the water yield of the cooling towers by the main control board to realize the balance among the cooling towers.

10. An air conditioning system, characterized in that the air conditioning system uses the method for adjusting the water inlet and outlet pressure balance of a water chilling unit according to claim 8.

Technical Field

The invention relates to the field of air conditioning systems, in particular to a water chilling unit, an inlet and outlet water pressure adjusting method thereof and an air conditioning system.

Background

The refrigerating unit in the air conditioning system realizes heat exchange through cold water and air cooling, and the refrigerating unit plays an important role in the refrigerating system in a cooling mode of a condenser. The water chilling unit is widely applied to air conditioning systems, and comprises a piston type water chilling unit, a centrifugal type water chilling unit, a screw type water chilling unit, a modular type water chilling unit and the like. Therefore, the detection of the water pressure of inlet and outlet water of the cooling water pressure of the condenser is very important, and particularly when the cooling towers are used in parallel, the water inlet amount needs to be adjusted through the valves to achieve the balance of water outlet amounts. Usually, the water chilling unit is provided with a pressure gauge and a thermometer at an inlet valve and an outlet valve to realize control detection, but the water chilling unit water inlet and outlet pressure regulation has hysteresis and imbalance according to the detection result, and the water chilling unit is easy to have potential safety hazards due to abnormal water pressure during working.

Therefore, how to solve the hysteresis and the imbalance of the water pressure regulation of the inlet water and the outlet water of the water chilling unit is an urgent technical problem to be solved in the industry.

Disclosure of Invention

The invention provides a water chilling unit, an inlet and outlet water pressure adjusting method thereof and an air conditioning system, and aims to solve the technical problems of hysteresis and imbalance of inlet and outlet water pressure adjustment of the water chilling unit in the prior art.

The invention provides a water chilling unit, which comprises at least two cooling towers which are used in parallel, and is characterized in that each cooling tower comprises a water pressure preposed adjusting circuit, a water pressure balance adjusting circuit and a main control board, wherein the main control board controls the water pressure preposed adjusting circuit to realize the real-time adjustment of the water yield of a single cooling tower, and controls the water pressure balance adjusting circuit to realize the water yield balance adjustment among a plurality of cooling towers.

Preferably, the water pressure prepositive adjusting circuit comprises a water pressure detection module, a water pressure control module and a first comparison module, wherein the first comparison module is used for comparing a control signal output by the water pressure control module with a water pressure detection signal output by the water pressure detection module and outputting a water output adjusting signal to the cooling tower water pump.

preferably, the first comparing module comprises a subtracter and an adder, the input signals of the subtracter are respectively the control signal output by the water pressure control module and the water pressure detection signal output by the water pressure detection module, the output signal of the subtracter and the control signal output by the water pressure control module are used as the input end of the adder, and the output end of the adder is used for controlling the adjustment of the water pump.

Preferably, the subtractor includes: the negative input end of the operational amplifier U9 receives the water pressure detection signal output by the water pressure detection module through a resistor, the positive input end of the operational amplifier U9 receives the control signal output by the water pressure control module through a resistor, the positive input end of the operational amplifier U9 is grounded through a resistor, the output end of the operational amplifier U9 is connected with the adder, and the output end of the operational amplifier U9 is connected with the negative input end of the operational amplifier U9 through a resistor.

Preferably, the adder includes: the positive input end of the operational amplifier U3 is connected with the output end of the subtracter through a resistor, the positive input end of the operational amplifier U3 is further connected with the output end of the water pressure control module through a resistor, the negative input end of the operational amplifier U3 is grounded through a resistor, and the output end of the operational amplifier U3 outputs a water pump control signal.

Preferably, the water pressure balance adjusting circuit comprises a balancing module, which is used for receiving a water pressure detection signal sent by the water pressure detection module of each cooling tower and a water pressure control signal sent by the main control panel; and the second comparison module is used for receiving and comparing output signals sent by the balance modules of the cooling towers and feeding back comparison results to the main control board, and the main control board adjusts water yield output control signals according to the comparison results to realize water yield balance among the cooling towers.

Preferably, the balancing module is composed of a differential amplifier, comprising: the operational amplifier U1, the operational amplifier U2 and the operational amplifier U4, the positive input end of the operational amplifier U2 connects the water pressure detection signal sent out by the water pressure detection module, the negative input end of the operational amplifier U2 connects to the negative input end of the operational amplifier U1 through a resistance, the output end of the operational amplifier U2 connects to the positive input end of the operational amplifier U4 through a resistance, the output end of the operational amplifier U2 connects to its negative input end through a resistance; the positive input end of the operational amplifier U1 is connected with a water pressure control signal sent by the main control board, the output end of the operational amplifier U1 is connected with the negative input end of the operational amplifier U4 through a resistor, and the output end of the operational amplifier U1 is also connected with the negative input end of the operational amplifier U1 through a resistor; the positive input terminal of the operational amplifier U4 is further grounded through a resistor, the output terminal of the operational amplifier U4 is connected to the input terminal of the second comparing module through a resistor, and the output terminal of the operational amplifier U4 is further connected to the negative input terminal thereof through a resistor.

Preferably, the second comparing module comprises: the negative input end of the operational amplifier U8 is connected to the output end of one balancing module through a resistor, the positive input end of the operational amplifier U8 is connected to the output end of the other balancing module through a resistor, the positive input end of the operational amplifier U8 is grounded through a resistor, the output end of the operational amplifier U8 feeds back the comparison result to the main control board, and the output end of the operational amplifier U8 is connected to the negative input end of the operational amplifier U8 through a resistor.

The invention also provides a method for adjusting the water pressure of the water chilling unit, which is characterized by comprising the following steps:

Step 1, detecting the water output of each cooling tower water pump in real time, comparing the water output with the water output by a main control board, and adjusting the water output of each cooling tower water pump according to a comparison result;

and 2, comparing output signals sent by the balance modules of the cooling towers, feeding the comparison result back to the main control board, and adjusting the water yield of the cooling towers by the main control board to realize the balance among the cooling towers.

The invention also provides an air conditioning system which is characterized by using the water chilling unit inlet and outlet water pressure balance adjusting method in claim 8.

Compared with the prior art, the invention has the following beneficial effects:

The water pressure adjusting method for the water chilling unit, provided by the invention, has the advantages that the water pressure of the water chilling unit can be adjusted in real time by detecting the water pressure of the water chilling unit and comparing the detected water pressure with the control water pressure, the detected water pressure of the water chilling unit is fed back to the main control board of the water chilling unit, the balance adjustment of the water pressure of the water chilling unit is realized through the control logic. The water pressure of the inlet and outlet water of the cooling towers can be extracted and compared with the control water pressure, the balance adjustment of the water pressure of the inlet and outlet water of the cooling towers is realized, and the potential safety hazard caused by abnormal water pressure during the working of the unit is avoided.

Drawings

FIG. 1 is a functional block diagram of the present invention;

FIG. 2 is a circuit schematic of a first comparison module;

FIG. 3 is a schematic diagram of a water pressure balance regulating circuit;

FIG. 4 is a flow chart of the control logic of the present invention.

Detailed Description

The principles and embodiments of the present invention are described in detail below with reference to the accompanying drawings.

The invention provides a method for adjusting water pressure in and out aiming at a water chilling unit with a plurality of cooling towers. According to the method, the water pressure of inlet and outlet water of the water chilling unit is detected and compared with the control water pressure, so that the water pressure of the water chilling unit can be adjusted in real time, the detected water pressure of the inlet and outlet water is fed back to a main control board of the water chilling unit, the balance adjustment of the water pressure of the inlet and outlet water is realized through control logic, and the balance of the refrigerating outlet water quantity is guaranteed; the water pressure of inlet and outlet water of a plurality of cooling towers is extracted and compared with the control water pressure, so that the balance adjustment of the water pressure of inlet and outlet water of the plurality of cooling towers is realized, and the potential safety hazard caused by abnormal water pressure during the working of the unit is avoided.

The water chilling unit comprises at least two cooling towers which are used in parallel, each cooling tower comprises a water pump, a water pressure prepositive regulating circuit, a water pressure balance regulating circuit and a main control board, the main control board controls the water pressure prepositive regulating circuit to realize the real-time regulation of the water yield of a single cooling tower, and controls the water pressure balance regulating circuit to realize the water yield balance regulation among a plurality of cooling towers.

fig. 1 is a schematic block diagram of a water chilling unit for performing water pressure balance adjustment of inlet and outlet water. The water chilling unit comprises two cooling towers which are used in parallel, wherein each cooling tower comprises a water pump, a water pressure preposed regulating circuit, a water pressure balance regulating circuit and a main control board.

The water pressure prepositive adjusting circuit comprises a water pressure detection module, a water pressure control module and a first comparison module. The water pressure detection module is used for detecting the water pressure of inlet and outlet water of the unit and respectively transmitting water pressure detection signals to the first comparison module, the water pressure balance adjustment circuit and the main control board; the water pressure control module receives a control signal from the main control panel, generates a water pressure control signal and transmits the water pressure control signal to the first comparison module; the first comparison module compares the received water pressure detection signal with the water pressure control signal, the comparison result is transmitted to the water pump control circuit, and the water pump control circuit controls the water pump to carry out water inlet and outlet water pressure balance adjustment according to the comparison result, so that the real-time performance of water pressure adjustment is realized. The main control board receives the water pressure detection signal, realizes balance adjustment of water pressure of inlet and outlet water through control logic, and ensures balance of refrigeration outlet water quantity.

The first comparing module comprises a subtracter and an adder, and fig. 2 is a schematic circuit diagram of the first comparing module, wherein the subtracter is composed of an operational amplifier U9, resistors R38, R33, R34 and R39, a negative input end of the operational amplifier U9 forms an input end VIN1 of the voltage comparator through a resistor R38, and the input end is connected to an output end of the water pressure detecting module and receives a water pressure detecting signal; the positive input end of the operational amplifier U9 forms the other input end VOUT1 of the voltage comparator through a resistor R33, the other input end VOUT is connected with the output end of the main control board and receives the water pressure control signal, and the output end of the operational amplifier is grounded through a resistor R34; the water pressure detection signal and the water pressure control signal are subjected to subtraction operation through an operational amplifier U9, the operation result is output to the adder through an output end, and the output end of the operational amplifier U9 is connected to the negative input end of the operational amplifier U3526 through another resistor R39.

The adder consists of an operational amplifier U3, a resistor R1, a resistor R2, a resistor R3 and a resistor R4, wherein the positive input end of the operational amplifier U3 is connected to the output end of the adder through a resistor R3, and the positive input end of the operational amplifier U3 is also connected to the output end of the main control panel through a resistor R4 and receives a water pressure control signal; the negative input terminal of the operational amplifier U3 is grounded through a resistor R1; the operation result of the operational amplifier U9 and the water pressure control signal are subjected to accumulation operation through the operational amplifier U3, and the accumulation operation result is transmitted to the water pump control circuit through the output end OUT1 to carry OUT water pressure balance adjustment of inlet and outlet water in real time.

The water pressure balance adjusting circuit comprises a balance module and a second comparison module, and the balance module is used for receiving a water pressure detection input signal output by the water pressure detection module and a water pressure control signal output by the main control board; the second comparison module is used for receiving and comparing signals sent by the balance modules of the cooling towers and feeding back comparison results to the main control board, and the main control board adjusts water yield output signals according to the comparison results to achieve water yield balance among the cooling towers.

The water pressure balance adjusting circuit is composed of 2 balancing modules and 1 second comparing module as shown in fig. 3, and the 2 balancing modules are arranged on the two cooling towers. Wherein the balancing module is composed of a differential amplifier, and the balancing module 1 comprises: the water pressure detection device comprises operational amplifiers U1, U2, U4, resistors R5, R8, R9, R21, R22, R23, R26 and R27, wherein the positive input end of the operational amplifier U2 is connected to the output end of the water pressure detection module and receives a water pressure detection input signal; the negative input end of the operational amplifier U2 is connected with the negative input end of another operational amplifier U1 through a resistor R9, the water pressure detection input signal is subjected to signal extraction through the operational amplifier U2, the extracted signal is connected with the positive input end of the differential amplifier U4 through a resistor R22 from the output end of the operational amplifier U2, and the extracted signal is also connected with the negative input end of the operational amplifier U2 through a resistor R5 from the output end of the operational amplifier U2; the positive input end of the operational amplifier U1 is connected with the output end of the main control board and receives a water pressure control signal, the water pressure control signal is subjected to signal extraction through the operational amplifier U1, the extracted signal is connected with the negative input end of the differential amplifier U4 through a resistor R21 by the output end of the operational amplifier U1, and the extracted signal is also connected with the negative input end of the operational amplifier U1 through a resistor R8 by the output end of the operational amplifier U1; the positive input terminal of the differential amplifier U4 is also connected to ground through a resistor R26; the water pressure detection input signal and the water pressure control signal of the cooling tower 1 are extracted by operational amplifiers U2 and U1 and then subjected to signal amplification through a differential amplifier U4, the amplified signals are connected to the negative input end of the second comparison module through a resistor R27 by the output end of the differential amplifier U4, and the output end of the differential amplifier U4 is further connected to the negative input end of the differential amplifier U4 through a resistor R23.

The other balancing module 2 is composed of operational amplifiers U5 and U6, a differential amplifier U7, an input terminal VIN2 and VOUT2, resistors R6, R7, R10, R11, R12, R13, R14 and R15, and the module has the same circuit structure, the same connection mode and the same function as the balancing module 1. The water pressure detection input signal and the water pressure control signal of the cooling tower 2 are extracted by the operational amplifiers U6 and U5 and then subjected to signal amplification by the differential amplifier U7, and the amplified signals are connected to the positive input end of the second comparison module through the output end of the differential amplifier U7 and a resistor R15.

The second comparison module includes: the negative input end of the operational amplifier U8 forms the negative input end of the second comparison module through a resistor R16, and is connected to one end of a resistor R27 of the balancing module 1; the positive input end of the operational amplifier U8 forms the positive input end of the second comparing module through a resistor R17, and is connected to one end of the resistor R15 of the balancing module 2, and the positive input end of the operational amplifier U8 is also grounded through a resistor R19; the output terminal of the operational amplifier U8 is the output terminal OUT2 of the second comparing module, and the output terminal of the operational amplifier U8 is further connected to the negative input terminal of the operational amplifier U8 through a resistor R18. The second comparison module receives the signals of the balance module 1 and the balance module 2 to perform subtraction operation, the operation result is transmitted to the main control board through the output end of the second comparison module, and the main control board sends a water pressure adjusting signal according to the operation result, so that the water yield among the 2 cooling towers is balanced, and the potential safety hazard caused by abnormal water pressure during the working of the 2 cooling towers is avoided.

Fig. 4 is a logic flow chart of a control logic of the water pressure balance adjustment method for inlet and outlet water, when the water chilling unit starts to work and the main control board is powered on, water pressure control signals are respectively output to the water pressure control modules and the balance adjustment circuits of the cooling towers 1 and 2, water pressure detection input signals from the water pressure detection circuits of the 2 cooling towers are simultaneously received, and the water pressure detection circuits also respectively output the water pressure detection input signals to the first comparison module and the water pressure balance adjustment circuit; further, the water pressure control circuits of the 2 cooling towers receive the water pressure control signals and output water pressure output control signals to the first comparison module; further, the first comparison modules of the 2 cooling towers compare the water pressure detection input signal with the water pressure output control signal, judge whether the water pressure of inlet and outlet water exceeds a preset range, if the water pressure of inlet and outlet water exceeds the preset range, output the comparison result to the water pump control circuit for water pressure adjustment, and if the water pressure of inlet and outlet water does not exceed the preset range, directly return to the initial flow; further, the water pressure balance adjusting circuits of the 2 cooling towers extract the received water pressure detection input signals and the water pressure control signals and amplify the extracted signals; further, the second comparison module compares the amplified signals and transmits a comparison result to the main control board; and further, the main control board judges whether the water pressure among the 2 cooling towers is balanced, if the water pressure is unbalanced, a water pressure adjusting signal is sent out to carry out water pressure balance adjustment, and if the water pressure is balanced, no operation is carried out.

The water chilling unit and the water inlet and outlet pressure adjusting method provided by the invention can be applied to an air conditioning system.

According to the water chilling unit, the water inlet and outlet pressure adjusting method and the air conditioning system, the water pressure of the water chilling unit can be adjusted in real time by detecting the water inlet and outlet pressure of the water chilling unit and comparing the water inlet and outlet pressure with the control water pressure, the detected water inlet and outlet pressure is fed back to the main control board of the water chilling unit, the water inlet and outlet pressure balance adjustment is achieved through control logic, and the balance of the refrigerating water outlet quantity is guaranteed. The water pressure of inlet and outlet water of a plurality of water chilling units can be extracted and compared with the control water pressure, the balance adjustment of the water pressure of inlet and outlet water of the water chilling units is realized, and the potential safety hazard caused by abnormal water pressure during the operation of the units is avoided.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.