Method, system and device for controlling the temperature of cooling medium in circulating cooling system

Abstract

The present invention belongs to the technical field of water circulation cooling detection and control, and specifically relates to a cooling medium temperature control method, system and equipment for a circulating cooling system, wherein the cooling medium temperature control method for a circulating cooling system comprises: obtaining a heat release control scheme in a circulating cooling system according to a cooling medium heat release detection method in the circulating cooling system; determining equipment problems and problem handling measures; and controlling according to the heat release control scheme and equipment abnormality handling measures to control the cooling medium temperature, thereby achieving rapid feedback, regularly predicting water temperature changes, rapidly raising and lowering temperatures, and avoiding sensor errors to accurately control temperature.

Description

Technical Field

[0001] The present invention belongs to the technical field of water circulation cooling detection and control, and in particular relates to a cooling medium temperature control method, system and equipment for a circulation cooling system. Background Art

[0002] At present, there are many problems in the circulating cooling system, mainly including:

[0003] 1. The water temperature changes with serious lag, there is no regularity and it is impossible to predict how the water temperature changes, the large volume of water makes it difficult to quickly increase / lower the temperature, and there are cumulative errors in the sensor, resulting in poor control effects;

[0004] 2. Manual control cannot adjust the equipment in optimization mode, so the power consumption is high.

[0005] Therefore, based on the above technical problems, it is necessary to design a new cooling medium temperature control method, system and equipment for a circulating cooling system. Summary of the invention

[0006] The object of the present invention is to provide a method, system and equipment for controlling the temperature of a cooling medium in a circulating cooling system.

[0007] In order to solve the above technical problems, the present invention provides a method for detecting the heat release of a cooling medium in a circulating cooling system, comprising:

[0008] Capture the heat energy absorbed by cooling water flowing through the incineration zone:

[0009] ;

[0010] in, E 1 is the heat energy absorbed by the cooling water flowing through the incineration zone during one operation cycle; msn For the n The mass of desalted water flowing through per second; cpn For the n Specific heat capacity of desalted water at constant pressure in seconds; T 1 n For the n Seconds T 1. Real-time desalted water temperature measured by the temperature sensor; T 6 n For the n Seconds T 6. Real-time desalted water temperature measured by temperature sensor; s is the set operation cycle;

[0011] Get the heat released by the second heat exchanger:

[0012] E 2= Σsn =1Q 2 ( T 1 n - T 2 n ), n =1,2,…, s ;

[0013] in, Q 2 is the first basic heat dissipation; T 1 n For the n Seconds T 1. Real-time desalted water temperature measured by the temperature sensor; T 2 n For the n Seconds T 2. Real-time desalted water temperature measured by temperature sensor; E 2 Heat released through the second heat exchanger during one operation cycle;

[0014] Get the heat released by the chute area:

[0015] ;

[0016] in, Q 7 is the second basic heat dissipation; T 7 n For the n Seconds T 7. Real-time desalted water temperature measured by temperature sensor; E 7 is the heat released by the chute area in one operation cycle;

[0017] Get the calculation result within one operation cycle SPt 1 Heat energy required:

[0018] ;

[0019] in, SPt 1 in 1~ s Seconds are always a fixed value K ; ESP To maintain K Temperature is the amount of heat energy that needs to be absorbed in one cycle;

[0020] The heat energy difference is ∆ E , then ∆ E = ESP - E 1;

[0021] ∆ E = ESP - E 1=-( E 6+ E 2+ E 7);

[0022] E 6 = E 1- ESP - E 2- E 7;

[0023] in, E 6 is the heat release of the first heat exchanger;

[0024] Get the final heat release of the first heat exchanger:

[0025] E 6'=|[1+ α ( T 1 S - SPt 1) ]|( E 1- ESP - E 2- E 7);

[0026] in, T 1 S The last moment of a calculation cycle T 1. Real-time desalted water temperature measured by the temperature sensor; α is the gain factor.

[0027] In a second aspect, the present invention also provides a method for controlling the temperature of a cooling medium in a circulating cooling system, comprising:

[0028] The above-mentioned method for detecting the heat release of the cooling medium in the circulating cooling system obtains a control scheme for heat release in the circulating cooling system;

[0029] Identify equipment problems and what to do about them; and

[0030] Control is performed according to the heat release control plan and equipment abnormality handling measures to control the cooling medium temperature.

[0031] Further, the scheme for controlling heat release in the circulating cooling system is:

[0032] Get the first heat exchanger pipeline b When fully closed, the entire desalted water flows in c The heat dissipation in the branch circuit is Ec ,when E 6'<= Ec , then adjust the three-way regulating valve V 1 Opening 0%, stop the variable frequency motor M 2;

[0033] Get the entire desalted water flow direction b Branch circuit and the variable frequency motor of the first heat exchanger M2 When the operating frequency is 100%, the heat dissipation is Eb ,when E 6'>= Eb , then adjust the three-way regulating valve V 1 opening 100%, variable frequency motor M 2 The operating frequency is 100% of the rated frequency;

[0034] when Ec < E 6'< Eb , first E 6' divided by the preset heat release time J Get the heat release per second, adjust the three-way regulating valve first V 1 opening to adjust the flow through the first heat exchanger, M 2Stop; when V 1Start when adjustment is not possible M 2. Increase the amount of refrigerant by frequency conversion; when the heat dissipation becomes smaller, no need M 2Run, then stop M 2;

[0035] when E 6'<= Ec Continue for a preset time, set T 1 Temperature lower limit T 1 L = X ,when T 1< X , reduce the total flow FT 1 is the original SPft 70% of 1; E 6'>= Eb Continue for a preset time, set T 1 Temperature upper limit T 1 H = Y , increase the total flow FT 1 is the original SPft 130% of 1; when within a cycle T 1Temperature restored to 1.05 X <= T 1<=0.95 Y range, the flow rate is restored to SPft 1.

[0036] Further, the method for determining equipment problems and problem handling measures includes:

[0037] The equipment problems include: instrument failure and equipment abnormality;

[0038] The instrument failure includes: real-time temperature sensor T 1~ T7. Real-time circulation total flow FT 1. Measure real-time pressure in the pipeline P 1 to judge the quality of the transmission data. If there is a disconnection and / or short circuit and / or the rise and fall rate is too fast, it indicates that the instrument is faulty.

[0039] Furthermore, the device abnormality includes:

[0040] The device cannot complete the command action within the specified time;

[0041] The device outputs a fault signal;

[0042] The device cannot perform automatic operations.

[0043] Furthermore, the method for determining equipment problems and problem handling measures also includes:

[0044] The problem solving measures include:

[0045] If an instrument failure or equipment abnormality occurs and the heat dissipation control cannot be performed, the operation will be stopped immediately, the operation cycle will be reset, and the calculation-related data values ​​will be cleared. At the same time, the human-machine interface will issue an operation stop alarm and indicate the reason for the stop;

[0046] When an equipment anomaly occurs and the control heat release plan cannot be executed, the control of the corresponding equipment is stopped and only the last operating state of the equipment is maintained. The subsequent action plan is cleared and the human-machine interface issues a control stop alarm to indicate the reason for the stop.

[0047] Further, the method for controlling the temperature of the cooling medium by controlling the heat release scheme and the equipment abnormality handling measures includes:

[0048] Preset required parameters S , α , X , Y ;

[0049] Control frequency conversion motor M 1 Press the set total flow SPft 1Run;

[0050] First, check whether the instrument equipment is abnormal. If it is abnormal, execute the corresponding treatment measures. Otherwise, determine whether the cycle is over. If it is not over, return to check the instrument equipment again. If it is over, store the data and obtain the control heat release plan.

[0051] Control the corresponding equipment according to the heat release control plan to control the temperature of the cooling medium.

[0052] In a third aspect, the present invention further provides a control system using the above-mentioned cooling medium temperature control method for a circulating cooling system, comprising:

[0053] The program formulation module obtains the control heat release program in the circulating cooling system;

[0054] Action development module to identify equipment problems and action to address them; and

[0055] The execution module controls the cooling medium temperature according to the heat release control plan and equipment abnormality handling measures.

[0056] In a fourth aspect, the present invention further provides a temperature control device using the above-mentioned cooling medium temperature control method for a circulating cooling system, comprising:

[0057] Control module, and three-way regulating valve controlled by the control module V 1. Frequency conversion motor M 1 and variable frequency motor M 2;

[0058] The control module is suitable for controlling the corresponding three-way regulating valve according to the heat release control scheme V 1. Frequency conversion motor M 1 and variable frequency motor M 2. To control the temperature of cooling medium.

[0059] The beneficial effects of the present invention are that the present invention obtains a heat release control scheme in a circulating cooling system according to a method for detecting the heat release of the cooling medium in the circulating cooling system; determines equipment problems and problem handling measures; and controls according to the heat release control scheme and equipment abnormality handling measures to control the cooling medium temperature, thereby achieving rapid feedback, regularly predicting water temperature changes, rapidly raising and lowering temperatures, and avoiding sensor errors to accurately control temperature.

[0060] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention are realized and obtained by the structures particularly pointed out in the description and the drawings.

[0061] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0063] Figure 1It is a flow chart of a method for controlling the temperature of a cooling medium in a circulating cooling system according to the present invention;

[0064] Figure 2 is a schematic diagram of the equipment involved in the present invention;

[0065] Figure 3 It is the control logic diagram involved in the present invention. DETAILED DESCRIPTION

[0066] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0067] This embodiment provides a method for detecting the heat release of a cooling medium in a circulating cooling system, which is characterized by comprising: obtaining the heat energy absorbed by cooling water flowing through an incineration zone:

[0068] ; in, E 1 is the heat energy absorbed by the cooling water flowing through the incineration zone during one operation cycle; msn For the n The mass of desalted water flowing through per second; cpn For the n Specific heat capacity of desalted water at constant pressure in seconds; T 1 n For the n Seconds T 1. Real-time desalted water temperature measured by the temperature sensor; T 6 n For the n Seconds T 6. Real-time desalted water temperature measured by temperature sensor; s For the set operation cycle; obtain the heat released by the second heat exchanger:

[0069] ;

[0070] in, Q 2 is the first basic heat dissipation; T 1 n For the n Seconds T 1. Real-time desalted water temperature measured by the temperature sensor; T 2 n For the n Seconds T 2. Real-time desalted water temperature measured by temperature sensor;E 2 The heat released by the second heat exchanger in one operation cycle; the heat released by the chute area is obtained:

[0071] ;

[0072] in, Q 7 is the second basic heat dissipation; T 7 n For the n Seconds T 7. Real-time desalted water temperature measured by temperature sensor; E 7 is the heat released by the chute area in one operation cycle; obtain the maintenance value calculated in one operation cycle SPt 1 Heat energy required:

[0073] ;

[0074] in, SPt 1 in 1~ s Seconds are always a fixed value K ; ESP To maintain K Temperature: one cycle requires the absorption of heat energy; the heat energy difference is ∆ E , then ∆ E = ESP - E 1;∆ E = ESP - E 1=-( E 6+ E 2+ E 7);

[0075] E 6 = E 1- ESP - E 2- E 7; among them, E 6 is the heat release of the first heat exchanger;

[0076] Get the final heat release of the first heat exchanger:

[0077] E 6'=|[1+ α ( T 1 S - SPt 1) ]|( E 1- ESP - E 2- E 7); among which, T 1 S The last moment of a calculation cycle T 1. Real-time desalted water temperature measured by the temperature sensor;α is the gain factor.

[0078] like Figures 1 - 3 As shown, the present embodiment also provides a method for controlling the temperature of a cooling medium in a circulating cooling system, comprising: obtaining a heat release control scheme in a circulating cooling system according to a method for detecting the heat release of the cooling medium in the circulating cooling system; determining equipment problems and problem handling measures; and controlling according to the heat release control scheme and equipment abnormality handling measures to control the cooling medium temperature, thereby achieving rapid feedback, regularly predicting water temperature changes, rapidly raising and lowering temperatures, and avoiding sensor errors to accurately control temperature.

[0079] In this embodiment, the specific device structure involved in the cooling medium temperature control method for the circulating cooling system can be: based on a certain control system platform ( PLC , DCS It is realized on the Internet (etc.), and the algorithm in the control method needs to be converted into execution code and human-machine interface. At the same time, the control system needs to collect real-time data on site, perform instant calculations through built-in algorithms, and then output the results to dynamically control the on-site equipment, and finally achieve the purpose of controlling the water temperature. It has the advantages of stability, reliability, high degree of automation, easy operation, and high safety. Another extremely beneficial benefit is to achieve energy saving and consumption reduction as much as possible by minimizing the control of high-power motor equipment; the circulation system is closed, so the entire pipeline is filled with liquid and has a high pressure, such as Figure 2 The equipment and circulation pipelines shown are connected to form a complete circulation system. The arrows in the figure indicate the direction of liquid flow. The incineration area refers to the area where waste is incinerated on the mechanical grate. There are several grate plates in the area. Each plate has a built-in circulation pipe through which cooling water flows and takes away part of the heat. This is an endothermic process, which is uncertain. The second heat exchanger (heat exchanger 2) refers to a heat exchange device (belonging to a wall-type heat exchanger) through a refrigerant (usually air), allowing the refrigerant to take away part of the heat. This is a heat release process. The refrigerant flow rate here is fixed. The chute area is the area where cooling water flows through for heat dissipation. This is a heat release process. The first heat exchanger (heat exchanger 1) refers to a heat exchange device (belonging to a wall-type heat exchanger) through a refrigerant (usually air). The refrigerant is regulated by frequency conversion, so that the amount of heat taken away can be controlled, which is also different from the second heat exchanger. M 1, M 2 is a variable frequency motor with variable frequency speed regulation. M 1 is a motor used to drive the circulation pump, providing kinetic energy for the circulation of desalted water. M 2 is a motor for adjusting the amount of refrigerant in the first heat exchanger. Both devices are connected to the control system. V 1 is a three-way regulating valve, a Water ingress, b , cThe inflow is equal to the total outflow, that is, FT ( a )= FT ( b )+ FT ( c ) principle, adjusting the valve opening can increase or decrease b The flow rate at c The flow rate at the place decreases or increases accordingly. V 1The larger the valve opening b The greater the flow at the location, the greater the access of the device to the control system. P 1 is the real-time pressure measured in the pipeline, and the data is connected to the control system. T 1~ T 7 is the real-time desalted water temperature measured by the temperature sensors at each point, and this data is connected to the control system. FT 1 is the real-time total circulation flow (instantaneous flow at a certain moment), and this data is connected to the control system.

[0080] In this embodiment, according to the Bernoulli equation, since it is a closed system, M 1 Most of the mechanical energy provided is converted into lost internal energy and finally into heat energy. Since there are many places for the equipment to dissipate heat (the surface area of ​​the pipe is large), it is found in the actual test that the motor M The mechanical energy of 1 has almost no effect on the temperature of the desalted water. Therefore, the control algorithm in the control method described in this embodiment does not take into account M 1. The influence of mechanical energy on water temperature control. At the same time, according to the requirements of the production process, it must be ensured that T 1 Temperature ( Figure 2 The outlet water temperature of the middle combustion zone is equivalent to the equipment with numbers in the following text. Figure 2 The device with the same number in the figure) is kept constant near a certain temperature value. On the basis of meeting this premise, it is best to automatically control the temperature in a way with minimum energy consumption. The control algorithms described in this invention are all developed around this goal. First, you need to set T 1The ideal control value of temperature is K , K To determine the process production temperature, here we use SPt 1 means, that is SPt 1= K .at the same time FT 1Preset an ideal total flow value U , here we use SPft 1 means, that is SPft 1= U These two are relatively reasonable parameters adjusted by process + equipment + testing. Then set the operation cycle to s Second( sis a specific value, which can be modified in the human-machine interface). This cycle is the time period during which the control system automatically calculates the heat.

[0081] In this embodiment, the scheme for controlling heat release in the circulating cooling system is: obtaining the heat energy absorbed by the cooling water flowing through the incineration zone according to the heat conduction theory calculation formula:

[0082] ;

[0083] in, E 1 is the heat energy absorbed by the cooling water flowing through the combustion zone during one operation cycle, in units of KJ ; msn For the n The quality of desalinated water flowing through the water per second (through real-time flow FT 1 times the density of deionized water ρ get); cpn For the n Specific heat capacity of desalted water at constant pressure in seconds, cpn Check reference books to get specific values ​​(pressure P 1 measurement value, the pressure is very stable during normal operation); T 1 n For the n Seconds T 1. Real-time desalted water temperature measured by the temperature sensor; T 6 n For the n Seconds T 6. Real-time desalted water temperature measured by temperature sensor; s is the set operation cycle; the above formula is to convert 1~ s The sum of the heat power per second in the second is the total heat absorbed by the desalted water in one operation cycle; for example, if the data in the first second is FT 1=220 m 3 / h , P 1=78 Kpa , ρ =1000 kg / m 3. cpn =0.98 kJ / kg , T 1 = 77 °C, T 6=71℃, heat energy in the first second Q 1 1 =220 / 3600*1000*0.98*(77-71)=359.3( kJ / s ); 2nd second data FT 1=223 m 3 / h , P 1=78 Kpa , ρ =1000 kg / m 3. cpn =0.98 kJ / kg , T 1 = 78 °C, T 6=71℃, heat energy in the second second Q 1 2 =223 / 3600*1000*0.98*(78-71)=424.9( kJ / s ),if S is 2 seconds, the total absorbed heat energy is E 1= Q 1 1 + Q 1 2 =784.2 KJ .

[0084] Since the second heat exchanger is a mature industrial product, the heat dissipation area, heat transfer coefficient, etc. are fixed values. Combined with the design formula given by the equipment manufacturer and through the analysis of the previous operation data, the modified heat release function relationship of the second heat exchanger is obtained (which can be regarded as an empirical formula), that is,

[0085] ;

[0086] in, Q 2 is the first basic heat dissipation (which can be regarded as a fixed constant); T 1 n For the n Seconds T 1. Real-time desalted water temperature measured by the temperature sensor; T 2 n For the n Seconds T 2. Real-time desalted water temperature measured by temperature sensor; E 2 is the amount of heat released by the second heat exchanger in one operation cycle; these parameters have been connected to the control system, and the heat released by the second heat exchanger in one operation cycle can be easily calculated by adding the heat calculated per second using the formula;

[0087] Since the chute is a mature industrial product, the heat dissipation area, heat transfer coefficient, etc. are fixed values. Combined with the design formula given by the equipment manufacturer and through the analysis of the previous operation data, the corrected chute heat release function relationship (which can be regarded as an empirical formula) is obtained, that is,

[0088] ;

[0089] in, Q 7 is the second basic heat dissipation; T 7 n For the n Seconds T 7. Real-time desalted water temperature measured by temperature sensor; E 7 is the heat released by the chute area in one operation cycle;

[0090] The circulation system is regarded as an independent thermal system, which conforms to the law of conservation of thermal energy. Therefore, it is necessary to ensure T 1 If the temperature is constant, it takes a period of time for the heat release and absorption in the system to reach a balance. The maintenance time is calculated within one operation cycle. SPt 1 The required heat energy is calculated using the heat conduction formula to maintain the energy within one operation cycle. SPt 1 Heat energy required:

[0091] ;

[0092] in, SPt 1 in 1~ s Seconds are always a fixed value K ; ESP To maintain K Temperature is the amount of heat energy that needs to be absorbed in one cycle; E 1 is regarded as the actual heat absorption;

[0093] The heat energy difference is ∆ E , then ∆ E = ESP - E 1. Need to maintain constant temperature K The difference in heat energy required;

[0094] ∆ E = ESP - E 1=-( E 6+ E 2+ E 7);

[0095] E 6 = E 1- ESP - E 2- E 7 (The values ​​in this formula are all positive numbers, and the calculated E If 6 is a positive number, heat release is required, and if it is a negative number, heat release is not required);

[0096] in, E 6 is the heat release of the first heat exchanger, T 3 Flow through T 6 heat release value in one cycle.E 1. ESP , E 2. E 7 are all calculated synchronously at the last moment of a certain operation cycle, and E The value of 6 must be known after the cycle ends, and then the first heat exchanger is controlled to release the calculated heat in the next cycle. E 1. ESP , E 2. E 7 is calculated again in the next cycle, and after the end, the next cycle starts to control the first heat exchanger to release a new heat value, and so on. E The release of 6 is always one cycle slower (that is, E 6 releases the excess heat generated in the previous cycle). Since the amount of desalted water in the entire circulation system is large and the specific heat capacity of desalted water is large, the circulation system is like a large energy storage tank. If the cycle time s If it is not too long, releasing heat slowly for one cycle is good. T 1Temperature control has no effect.

[0097] The instrument measurement value also has a certain error. If it runs for a long time, the cumulative error will also cause the temperature T 1 gradually exceeds the standard, so the gain factor needs to be introduced here α , the gain coefficient can be set in the human-machine interface, and the final calculated E The product of 6 and the actual temperature difference gain is the heat release value required by the final heat exchanger 1, and the heat release of the final first heat exchanger is obtained:

[0098] E 6'=|[1+ α ( T 1 S - SPt 1) ]|( E 1- ESP - E 2- E 7);

[0099] in, T 1 S The last moment of a calculation cycle T 1. Real-time desalted water temperature measured by the temperature sensor; α is the gain coefficient; E 6' The result is obtained only after a calculation cycle ends; when the accumulated error causes T The larger the 1 liter, the more heat will be released in the next cycle, so this is also a guarantee. T 1Effective measures for temperature stability.

[0100] In this embodiment, the heat release control scheme for obtaining the circulating cooling system can also be: different E 6' value must correspond to different control strategies, and also need to take into account the energy saving effect, and also can not make the equipment move too much to cause system oscillation; the early determination of heat exchanger 1 pipeline b When fully closed, the entire desalted water flows to c The heat dissipation in the branch circuit is Ec (Here Ec is a positive number, even if heat exchanger 1 is not enabled, the pipeline still has a certain heat dissipation effect). Ec is the minimum heat release, which can be regarded as a fixed constant. E 6'<= Ec , then adjust V 1 Opening 0% (see above V 1 description), stop M 2 motors, usually set to move within 5 seconds. b When the branch circuit is connected, the motor of heat exchanger 1 M 2 When the operating frequency is 100%, the heat dissipation is Eb (Here Eb is a positive number), Eb is the maximum heat release, which can be regarded as a fixed constant. E 6'>= Eb , then adjust V 1 opening 100%, M 2 The motor operating frequency is 100% of the rated frequency and is generally set to operate within 5 seconds.

[0101] when Ec < E 6'< Eb , first E 6' divided by the preset heat release time J ( J < S , which can be modified in the human-machine interface) to obtain the heat release per second. In the early stage, the data on the relationship between the desalted water flow, the refrigerant volume and the heat release of the heat exchanger 1 were obtained. The heat exchanger 1 is also a mature industrial product. The flow-refrigerant volume-heat release line table provided by the equipment manufacturer was corrected through the actual test data, and then the corrected line table was built into the control system. In this way, the specific values ​​of the flow and refrigerant flow can be obtained by the table lookup method under the condition of known heat release; in addition, according to V 1's inherent flow characteristics and the actual on-site measurement also obtained V 1 Opening and b Branch flow curve table, and then the curve table is also built into the control system, and the same can be obtained M2 Frequency and refrigerant flow curve table. In this way, after each value is output, the algorithm can adjust the valve according to the built-in curve table. V 1. Adjust M 2 principle to control heat release. V 1 opening to adjust the flow through the heat exchanger 1 ( b Branch Road), M 2Stop; when V 1. If the opening cannot be adjusted (i.e., the 100% opening cannot be adjusted), the M 2 motors, increase the amount of refrigerant by frequency conversion; if the heat dissipation at the back becomes smaller, no need M 2 The motor is running, then stop M 2 motors; and so on.

[0102] when E 6'<= Ec If the duration is long, the system will lack heat for a long time, resulting in a drop in the overall temperature, which does not meet the process requirements. T 1 Temperature lower limit T 1 L = X ( X Can be modified in the human-machine interface). T 1< X , reduce the total flow FT 1 is the original SPft 70% of 1 (i.e. 0.7 U ), so as to reduce the heat taken away by the circulation system by reducing the flow rate of desalted water, and at the same time alarm on the human-machine interface, the alarm content is: low temperature combustion alarm, here the alarm information only reminds personnel to pay attention, without any control action; when E 6'>= Eb If the duration is long, the system will accumulate heat for a long time, causing the overall temperature to rise. T 1 Temperature upper limit T 1 H = Y ( Y Can be modified in the human-machine interface). T 1> Y , increase the total flow FT 1 is the original SPft 130% of 1 (i.e. 1.3 U ), which increases the heat taken away by the circulation system by speeding up the flow of desalted water. At the same time, an alarm is displayed on the human-machine interface. The alarm content is: high temperature combustion alarm. The alarm information here is also to remind personnel to pay attention, without any control action. Only in a certain period later T 1Temperature restored to 1.05 X <= T 1<=0.95 Yrange, the flow rate is restored to U value, and the alarm information will automatically reset. Otherwise, keep pressing the button to reduce or increase the total flow rate. FT 1 to continue running. If the heat is too low, it will be fully closed; if the heat is too high, it will be fully opened. In the middle of the heat, the medium flow rate is obtained by looking up the table. If only the valve is opened, the valve is opened first, and the motor is turned on only when it is used. If T 1 reaches the limit, then reduce\increase the total flow and then execute. T 1 The cooling water returns to the preset value only when it returns to the normal range; the precise control performance of the cooling equipment is obtained through the table lookup method and empirical formula, and the equipment operation is controlled according to the optimized plan to achieve a more energy-saving effect than before; the gain coefficient and setting range are used to automatically and accurately control the water temperature fluctuation within a small range.

[0103] In this embodiment, the method for determining equipment problems and problem handling measures includes: some equipment problems occur in actual operation, such as gear jamming, low voltage and other faults. If the operator ignores them, it will cause production accidents. Therefore, it is necessary to add automatic handling measures in this regard to the control algorithm, otherwise the equipment will either malfunction and cause production accidents, or not operate and affect the next step of the algorithm execution; the equipment problems include: instrument failure and equipment abnormality; the instrument failure includes: real-time temperature sensor T 1~ T 7 ( T 4~ T 5 can be excluded, they only monitor and do not participate in control), real-time circulation total flow FT 1. Determine the real-time pressure in the pipeline P 1. The quality of the transmission data is judged. When disconnection and / or short circuit and / or rising and falling rate is too fast, it indicates that the instrument is faulty. The concept of instrument recovery means that once the instrument fails, the instrument fault information (including the instrument code and the type of fault, etc.) will be kept in this algorithm until it is repaired and manually reset to restore to normal.

[0104] In this embodiment, the device abnormality includes: the device to be controlled on site cannot complete the command action within the specified time due to jamming, overloading, etc. V 1 Open to 100%, wait for a while and then the feedback signal will indicate V 1 is only opened to 80%, indicating that some reason V 1. It cannot be opened properly or the movement is extremely slow, which is definitely abnormal. V 1. There is an abnormality. The equipment that needs to be controlled on site outputs a fault signal (motor overcurrent, low voltage, etc.) to the control system, such as V 1 During operation, the valve over-torque signal is suddenly output to the control system, which indicates V1. A mechanical failure has occurred. The equipment that needs to be controlled on site does not allow the control system to operate automatically for some reason, such as V 1 Equipment on-site maintenance, maintenance personnel will control the source button gear to select "local", which means V 1The valve cannot be remotely controlled. At this time, we also classify this situation as V 1. An abnormal situation occurs. The concept of equipment recovery means that once an abnormality occurs, the abnormal information (including the equipment code and the type of abnormality that occurred, etc.) will be kept in the control algorithm until it is repaired and manually reset. This is considered to be restored to normal. In the control algorithm, if you want to check whether the instrument or equipment is abnormal, you only need to query the relevant fault or abnormal information. Similarly, if you want to check whether the instrument or equipment has returned to normal, you only need to query whether the relevant status has returned to normal.

[0105] In this embodiment, the method for determining equipment problems and problem handling measures also includes: The problem handling measures include: in the event of an instrument failure or equipment abnormality, even if the control system calculates the result, it will not have any effect on the heat dissipation control, so the handling measures are also executed for the operation cycle, specifically immediately stopping the operation, resetting the operation cycle, clearing the calculation-related data values, and at the same time the human-machine interface issues a calculation stop alarm and indicates the reason for the stop. To facilitate maintenance personnel to quickly repair. In the event of equipment abnormalities, the heat release control plan will be affected, so the handling measures are executed for the control equipment action, specifically stopping the control of the corresponding equipment to continue to act, and only maintaining the last operating state of the equipment, clearing the subsequent action plan, and at the same time the human-machine interface issues a control stop alarm to indicate the reason for the stop. To facilitate maintenance personnel to quickly repair. When an abnormality occurs, it is always necessary to manually solve the on-site problem. At this time, the heat dissipation equipment action of the entire system has not changed, although it will not be affected in a short time. T 1 temperature. However, the operator still needs to repair the fault as soon as possible. If it has been repaired, the operator will reset the alarm and the control system will re-run the calculation cycle. If it cannot be repaired, it will be transferred from automatic to manual control.

[0106] Let's take an example to illustrate: If K =75℃, S = 30 seconds, α =0.1, U =300 m 3 / h , X =65℃, Y =92℃, J = 29 seconds, Ec =400 KJ , Eb =4300 KJ ;

[0107] No.n At the end of the operation cycle, it is calculated E 1 = 10000 KJ , ESP =7000 KJ , E 2=1000 KJ , E 7=800 KJ , T 1=85℃ E 6'=|[1+0.1 x (85-75)]|(10000-7000-1000-800)=2400 KJ Then heat exchanger 1 should dissipate 2400 / 29=82.8 KJ , at this time n +1 operation cycle starts, and at the same time the control system obtains the flow rate of heat exchanger 1 by looking up the table as 214 m 3 / h , the refrigerant volume is 0, and the best solution for this flow rate is V 1 opening 84%, M 2 is not running. Under normal circumstances, it can be put into action in a very short time. For a 30-second operation cycle, the impact of the device's response speed on the heat dissipation process is negligible. n +1 operation cycle is not obtained E 1 = 11000 KJ , ESP =7000 KJ , E 2=1000 KJ , E 7=800 KJ , T 1=85℃ E 6'=|[1+0.1 x (83-75)]|(11000-7000-1000-800)=3960 KJ Here, heat exchanger 1 should dissipate 136.5 KJ , the flow rate through heat exchanger 1 is 290 m 3 / h , the refrigerant volume is 30 m 3 / h Adjust V 1 opening 100%, M 2 frequency is 15%, and so on.

[0108] If extreme circumstances occur, m End of period E 1 = 5500 KJ , ESP =7000KJ , E 2=300 KJ , E 7=200 KJ , T 1=63℃, then E 6'=|[1+0.1 x (63-75)]|(5500-7000-300-200)=-400 KJ , and also belongs to T 1< X , then the corresponding V 1 opening 0%, M 2 is not running, the flow rate is reduced to 210 m 3 / h , the interface displays a low temperature combustion alarm. m +1 cycle calculated flow base value becomes 210 m 3 / h .exist p End of period E 1 = 13000 KJ , ESP =7000 KJ , E 2=2000 KJ , E 7=1200 KJ , T 1=93℃, then E 6'=|[1+0.1 x (93-75)]|(13000-7000-2000-1200)=7840 KJ , T 1> Y correspond V 1 opening 100%, M 2Frequency 100% operation, flow rate increased to 390 m 3 / h The interface displays a high temperature combustion alarm. If n After cycles T 1=85℃ is 1.05 X <= T 1<=0.95 Y , the total flow rate is reduced to 300 m 3 / h .

[0109] If in the r In a cycle T 1. If the line is suddenly disconnected and the temperature suddenly rises to 400℃, the algorithm will stop the calculation and clear the relevant calculation values ​​if it detects a fault in the instrument. The interface will display T1. If the fault is not restored, the operation cycle will not proceed, even after several cycles. V 1. M 2 will not take any action and will just maintain the original state.

[0110] In this embodiment, the method for controlling the temperature of the cooling medium by controlling the heat release scheme and the equipment abnormality handling measures includes: presetting the required parameters S , α , X , Y ;Control variable frequency motor M 1 Press the set total flow SPft 1. Run; first check whether the instrument equipment is abnormal, and execute corresponding treatment measures if abnormal, otherwise determine whether the cycle is over, if not, return to check the instrument equipment again, if it is over, store data and obtain control heat release plan; control corresponding equipment according to the control heat release plan to control the temperature of cooling medium.

[0111] Specifically, preset the required parameters S , α , X , Y etc. Starting the system operation refers to controlling the motor M 1 Press the set total flow U To operate, by building in the control system M 1Frequency-flow curve and query the curve to get the motor M 1 operating frequency, and the control system comes with PID Function fine-tuning M 1 frequency makes the system flow quickly tend to stabilize U The frequency-flow characteristic curve is an inherent property of the pump and is given by the equipment manufacturer. Next, the periodic operation begins. First, the instrument equipment is checked for abnormalities. There are two directions here. One is to execute the treatment measures if an abnormality occurs, and then wait for the abnormality to be repaired and reset the alarm. It should be noted that at this time, the entire algorithm keeps polling whether the fault is repaired and does not perform any other calculations. If it is repaired in a short time, it returns to restart the operation. If it cannot be repaired for more than 30 minutes, the control system stops the algorithm and switches to manual control.

[0112] The second direction is to perform the next operation if there is no abnormality, and then determine whether the cycle is over. If not, return to test the instrument equipment again, and then perform the next calculation, and so on. If it is over, store the data and get the control heat release plan.

[0113] Next, the next operation cycle begins. Two branches are carried out at the same time. One branch returns to continue the cycle operation; the other branch executes the control action specified by the control heat release scheme. First, it detects whether the corresponding equipment to be acted is abnormal. If there is an abnormality, it will turn to the treatment measures and unconditionally enter the execution completion process. If there is no abnormality, the next control action will be executed. Because the control device is not in place in one step, it is necessary to determine whether the corresponding plan has been executed after each execution. If it is not executed, it will return to continue to detect whether the corresponding equipment is abnormal, and then continue to control the device to act. After the plan is executed, it will unconditionally enter the execution completion process. It should be noted that there is no next step after the plan is executed. Only when the next cycle is opened can a new round of control plans be executed. In this way, as long as there is no abnormality, automatic control can be continued. Once only the instrument fails, the cycle operation must be stopped, but the control scheme will not stop to execute all actions. If the equipment fails, the cycle operation and the control device will stop at the same time. The purpose of this is to ensure the safety of the equipment and reflect the flexibility of the algorithm, so that the entire algorithm will not stagnate due to a problem. One-key start and stop algorithm operation is easy to operate. The implementation cost is low, only a small number of instrument valves are involved in the control, and the main work of implementation is program writing, which basically has no cost. It has high safety and reliability. When the algorithm is executed, the equipment status is queried to prevent personal accidents caused by erroneous actions on site. When automatic control cannot be performed for some reason, an automatic alarm is automatically given to remind personnel to control manually. The control algorithm adopts a retention-type information record, which is convenient for root tracing, data analysis and other in-depth research. The control algorithm architecture is modular, the logic is simple, and the ideas are clear. It is also convenient to add other functions to the control algorithm. It is convenient for engineers to maintain and modify. The control algorithm adopts periodic operation, and the control equipment also acts once in a cycle, and sometimes even does not need to act. This solves the problem that the frequent actions of the previous control equipment cause the equipment to age and increase the failure rate. In addition, the algorithm can also intelligently calculate the control instructions without relying on the feedback signal to act on the equipment, preventing the interference of the feedback signal from causing the equipment to act randomly and blindly, and the control is in place at one time to prevent the generation of eddy currents or surges in the closed system to damage the equipment, which has great benefits for equipment protection; automatic operation, automatic calculation, automatic monitoring of data, fast response, no dead angle, improve production efficiency, reduce labor intensity, and is welcomed by operators.

[0114] This embodiment also provides a control system that uses a cooling medium temperature control method for a circulating cooling system, including: a plan formulation module, which obtains a heat release control plan in the circulating cooling system; a measure formulation module, which determines equipment problems and problem handling measures; and an execution module, which controls according to the heat release control plan and equipment abnormality handling measures to control the cooling medium temperature.

[0115] In this embodiment, the specific functions of each module have been described in detail and will not be repeated here.

[0116] This embodiment also provides a temperature control device using a cooling medium temperature control method for a circulating cooling system, comprising: a control module, and a three-way regulating valve controlled by the control module V 1. Frequency conversion motor M 1 and variable frequency motor M 2; The control module is suitable for controlling the corresponding three-way regulating valve according to the heat release control scheme V 1. Frequency conversion motor M 1 and variable frequency motor M 2. To control the temperature of cooling medium.

[0117] In this embodiment, the control module uses the cooling medium temperature control method for the circulating cooling system to generate a control heat release scheme, etc., and controls the corresponding three-way regulating valve V 1. Frequency conversion motor M 1 and variable frequency motor M 2. To control the temperature of cooling medium.

[0118] In this embodiment, the specific structure of the device has been described in detail and will not be repeated here.

[0119] In summary, the present invention obtains a control heat release scheme in a circulating cooling system through a method for detecting the heat release of the cooling medium in the circulating cooling system; determines equipment problems and problem handling measures; and controls according to the control heat release scheme and equipment abnormality handling measures to control the cooling medium temperature, thereby achieving rapid feedback, regularly predicting water temperature changes, rapidly raising and lowering temperatures, and avoiding sensor errors to accurately control temperature.

[0120] In several embodiments provided in the present application, it should be understood that the disclosed devices and methods can also be implemented in other ways. The device embodiments described above are merely schematic. For example, the flowcharts and block diagrams in the accompanying drawings show the possible architecture, functions and operations of the devices, methods and computer program products according to multiple embodiments of the present invention. In this regard, each box in the flowchart or block diagram can represent a module, a program segment or a part of a code, and the module, a program segment or a part of a code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two consecutive boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram and / or flowchart, and the combination of boxes in the block diagram and / or flowchart can be implemented with a dedicated hardware-based system that performs a specified function or action, or can be implemented with a combination of dedicated hardware and computer instructions.

[0121] In addition, the functional modules in the various embodiments of the present invention may be integrated together to form an independent part, or each module may exist independently, or two or more modules may be integrated to form an independent part.

[0122] If the functions are implemented in the form of software function modules and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U Disk, mobile hard disk, read-only memory ( ROM , Read - OnlyMemory ), Random Access Memory ( RAM , RandomAccessMemory ), magnetic disks, optical disks, and other media that can store program codes.

[0123] Based on the above ideal embodiments of the present invention, the relevant staff can make various changes and modifications without departing from the technical concept of the present invention through the above description. The technical scope of the present invention is not limited to the contents of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A method for controlling the temperature of a cooling medium in a circulating cooling system, characterized in that: include: The heat release control scheme in the circulating cooling system is obtained by using the heat release detection method of the cooling medium in the circulating cooling system; Identify equipment problems and problem resolution actions; as well as Control the cooling medium temperature according to the heat release control plan and equipment abnormality handling measures; Wherein, the method for detecting the heat release of the cooling medium in the circulating cooling system comprises: Capture the heat energy absorbed by cooling water flowing through the incineration zone: ； Among them, E1 is the heat energy absorbed by the cooling water flowing through the incineration zone in one operation cycle; msn is the mass of desalted water flowing through the nth second; cpn is the constant pressure specific heat capacity of desalted water at the nth second; T1n is the real-time desalted water temperature measured by the T1 temperature sensor at the nth second; T6n is the real-time desalted water temperature measured by the T6 temperature sensor at the nth second; s is the set operation cycle; Get the heat released by the second heat exchanger: ； Wherein, Q2 is the first basic heat dissipation; T1n is the real-time desalted water temperature measured by the T1 temperature sensor at the nth second; T2n is the real-time desalted water temperature measured by the T2 temperature sensor at the nth second; E2 is the heat released by the second heat exchanger in one operation cycle; Get the heat released by the chute area: ； Among them, Q7 is the second basic heat dissipation; T7n is the real-time desalted water temperature measured by the T7 temperature sensor at the nth second; E7 is the heat released by the chute area in one operation cycle; Get the thermal energy required to maintain SPt1 within one operation cycle: ； Among them, SPt1 is always a fixed value K in 1~s seconds; ESP is the heat energy required to absorb in one cycle to maintain the temperature of K; The heat energy difference is ∆E, then ∆E=ESP- E1; ∆E=ESP- E1=-(E6+E2+E7); E6 = E1- ESP-E2-E7; Among them, E6 is the heat release of the first heat exchanger; Get the final heat release of the first heat exchanger: E6'=|[1+α(T1S- SPt1) ]|(E1- ESP-E2-E7); Wherein, T1S is the real-time desalted water temperature measured by the T1 temperature sensor at the last moment of a calculation cycle; α is the gain coefficient; and T1 is the outlet water temperature of the incineration zone, T6 is the incineration zone inlet water temperature, T2 is the outlet water temperature of the second heat exchanger, and T7 is the outlet water temperature of the chute zone; and the ideal control value of T1 temperature is set to K, K is the determined process production temperature, and is represented by SPt1, that is, SPt1=K; The first heat exchanger and the second heat exchanger are devices for heat exchange through refrigerant, the refrigerant of the first heat exchanger has its flow rate regulated by frequency conversion, and the refrigerant flow rate of the second heat exchanger is fixed; M1 and M2 are variable-frequency motors that can adjust the speed variably. Among them, M1 is the motor for driving the circulation pump, providing the kinetic energy for the recirculation of demineralized water; M2 is the motor for adjusting the refrigerant amount of the first heat exchanger. Both motors are connected to the control system. V1 is a three-way regulating valve, a is the inlet water, b and c are the outlet waters, and its inflow equals the total outflow, that is, it follows the principle of FT(a)=FT(b)+FT(c). Adjust the opening of the three-way regulating valve V1 to increase or decrease the flow rate at b, and at the same time, the flow rate at c decreases or increases correspondingly. The larger the valve opening of the three-way regulating valve V1, the larger the flow rate at b. The three-way regulating valve V1 is connected to the control system.

2. The method for controlling the temperature of a cooling medium in a circulating cooling system according to claim 1, characterized in that: The method for obtaining the control heat release scheme in the circulating cooling system is as follows: Obtain the heat dissipation Ec when the entire demineralized water flows to the c branch when the pipeline b of the first heat exchanger is fully closed. When E6' <= Ec, adjust the opening of the three-way regulating valve V1 to 0% and stop the variable-frequency motor M2; Obtain the heat dissipation Eb when the entire demineralized water flows to the b branch and the operating frequency of the variable-frequency motor M2 of the first heat exchanger is 100%. When E6' >= Eb, adjust the opening of the three-way regulating valve V1 to 100%, and the operating frequency of the variable-frequency motor M2 is 100% of the rated frequency; When Ec < E6' < Eb, first divide E6' by the preset heat release time J to obtain the heat that needs to be released per second. First, adjust the opening of the three-way regulating valve V1 to adjust the flow rate through the first heat exchanger, and M2 stops. When V1 cannot be adjusted, then start M2 and increase the refrigerant amount by frequency conversion. When the heat dissipation becomes small and M2 is not needed to operate, then stop M2; When E6' <= Ec lasts for a preset time, set the lower limit T1L of the T1 temperature to X. When T1 < X, reduce the total flow rate FT1 to 70% of the original SPft1. When E6' >= Eb lasts for a preset time, set the upper limit T1H of the T1 temperature to Y, and increase the total flow rate FT1 to 130% of the original SPft1. When the T1 temperature returns to the range of 1.05X <= T1 <= 0.95Y within one cycle, the flow rate returns to SPft1.

3. The method for controlling the temperature of a cooling medium in a circulating cooling system according to claim 2, characterized in that: The method for determining equipment problems and problem handling measures includes: The equipment problems include: instrument failures and equipment abnormalities; The instrument failures include: real-time quality judgment on the transmission data of the temperature sensors T1~T7, the real-time total circulation flow rate FT1, and the real-time pressure P1 measured in the pipeline. When there is a disconnection and / or short circuit and / or too fast rise and fall rate, it indicates an instrument failure.

4. The method for controlling the temperature of a cooling medium for a circulating cooling system according to claim 3, characterized in that: The equipment abnormalities include: The equipment fails to complete the command action within the specified time; The equipment outputs a fault signal; The equipment cannot perform automatic operations.

5. The method for controlling the temperature of a cooling medium for a circulating cooling system according to claim 4, characterized in that: The method for determining equipment problems and problem handling measures also includes: The problem handling measures include: For instrument failures or equipment abnormalities, when the heat dissipation control cannot be performed, immediately stop the operation, reset the operation cycle, clear the calculation-related data values, and at the same time, the human-machine interface issues an operation stop alarm and indicates the reason for the stop; When equipment abnormalities cause the control heat release scheme to be unable to be executed, stop the control of the corresponding equipment from continuing to operate, and only maintain the previous operating state of the equipment, clear the subsequent action plan, and at the same time, the human-machine interface issues a control stop alarm indicating the reason for the stop.

6. The method for controlling the temperature of a cooling medium in a circulating cooling system according to claim 5, characterized in that: The method for controlling the temperature of the cooling medium by controlling the heat release scheme and the equipment abnormality handling measures includes: Preset the required parameters S, α, X, Y; Control the variable frequency motor M1 to run according to the set total flow rate SPft1; First, check whether the instrument equipment is abnormal. If it is abnormal, execute the corresponding treatment measures. Otherwise, determine whether the cycle is over. If it is not over, return to check the instrument equipment again. If it is over, store the data and obtain the control heat release plan. Control the corresponding equipment according to the heat release control plan to control the temperature of the cooling medium.

7. A control system using the cooling medium temperature control method for a circulating cooling system according to any one of claims 1 to 6, characterized in that: include: The program formulation module obtains the control heat release program in the circulating cooling system; Measures formulation module, to identify equipment problems and measures to deal with them; as well as The execution module controls the cooling medium temperature according to the heat release control plan and equipment abnormality handling measures.

8. A temperature control device using the cooling medium temperature control method for a circulating cooling system as claimed in any one of claims 1 to 6, characterized in that: include: A control module, and a three-way regulating valve V1, a variable frequency motor M1 and a variable frequency motor M2 controlled by the control module; The control module is suitable for controlling the corresponding three-way regulating valve V1, the variable frequency motor M1 and the variable frequency motor M2 according to the heat release control scheme to control the temperature of the cooling medium.

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