WO2023138325A1 - Cooling medium temperature regulation and control method, system and device for circulating cooling system - Google Patents

Abstract

Provided are a cooling medium temperature regulation and control method, system and device for a circulating cooling system. The cooling medium temperature regulation and control method for a circulating cooling system comprises: obtaining a heat release control solution in a circulating cooling system according to a detection method for a heat release amount of a cooling medium in the circulating cooling system; determining a device problem and a problem handling measure; and performing control according to the heat release control solution and a device exception handling measure, so as to control the temperature of the cooling medium. By means of the method, rapid feedback is realized, a water temperature change is regularly predicted, rapid heating and cooling are realized, errors of a sensor are avoided, and the temperature is precisely controlled.

Description

Cooling medium temperature control method, system and equipment for circulating cooling system technical field

The 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 technique

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

1. The water temperature change lags behind seriously, there is no law to predict how the water temperature will change, the water volume is large and it is difficult to quickly raise/cool the temperature, and the sensor has accumulated errors, etc., resulting in poor control effect;

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

Therefore, based on the above technical problems, it is necessary to design a new cooling medium temperature control method, system and equipment for circulating cooling systems.

Contents of the invention

The object of the present invention is to provide a cooling medium temperature control method, system and equipment for a circulating cooling system.

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

Capturing the absorbed thermal energy where the cooling water flows through the incineration zone:

Among them, E1 is the heat energy absorbed by the cooling water flowing through the incineration area in one operation cycle; msn is the mass of desalinated water flowing through in the nth second; cpn is the specific heat capacity of the desalinated water at constant pressure at the nth second; T1n is the real-time desalinated water temperature measured by the T1 temperature sensor at the nth second; T6n is the real-time desalinated water temperature measured by the T6 temperature sensor at the nth second; s is the set calculation cycle;

Obtain the heat release through the second heat exchanger:

Among them, Q2 is the first basic heat dissipation; T1n is the real-time desalinated water temperature measured by the T1 temperature sensor at the nth second; T2n is the real-time desalinated water temperature measured by the T2 temperature sensor at the nth second; E2 flows through the second heat exchanger to release heat in one calculation cycle;

Obtain the heat release through the chute zone:

Among them, Q7 is the second basic heat dissipation; T7n is the real-time desalinated water temperature measured by the T7 temperature sensor at the nth second; E7 is the heat release in the chute area within one calculation cycle;

Obtain the heat energy required to maintain SPt1 in one calculation cycle:

Among them, SPt1 is always a fixed value K from 1 to s seconds; ESP needs to absorb heat energy in one cycle to maintain K temperature;

The thermal energy difference is ΔE, then ΔE=ESP-E1;

ΔE=ESP-E1=-(E6+E2+E7);

E6=E1-ESP-E2-E7;

Wherein, 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);

Among them, T1S is the real-time desalinated water temperature measured by the T1 temperature sensor at the last moment of the end of a calculation cycle; α is the gain coefficient.

In a second aspect, the present invention also provides a cooling medium temperature control method for a circulating cooling system, comprising

The heat release control scheme in the circulating cooling system is obtained by the above method for detecting the heat release of the cooling medium in the circulating cooling system;

Identify equipment problems and problem-solving actions; and

Control according to the heat release control plan and equipment abnormal treatment measures to control the temperature of the cooling medium.

Further, the control exothermic scheme in the said obtaining circulating cooling system is:

When the first heat exchanger pipeline b is fully closed, the heat dissipation when the entire desalted water flows to the c branch is Ec. When E6'<=Ec, adjust the opening of the three-way regulating valve V1 to 0%, and stop the frequency conversion motor M2;

When the entire desalinated water flows to the b branch and the heat dissipation is Eb when the frequency conversion motor M2 of the first heat exchanger operates at 100%, when E6'>=Eb, adjust the opening of the three-way regulating valve V1 to 100%, and the frequency conversion motor M2 operates at 100% of the rated frequency;

When Ec<E6'<Eb, first divide E6' by the preset heat release time J to obtain the required heat release per second, adjust the flow through the first heat exchanger according to the opening of the three-way regulating valve V1, and stop M2; when V1 cannot be adjusted, start M2, and increase the amount of refrigerant through frequency conversion; when the heat dissipation becomes smaller and does not need M2 to operate, then stop M2;

When E6'<=Ec lasts for the preset time, set the lower limit of T1 temperature T1L=X, and when T1<X, reduce the total flow FT1 to 70% of the original SPft1; when E6'>=Eb for the preset time, set the upper limit of T1 temperature T1H=Y, increase the total flow FT1 to 130% of the original SPft1;

Further, the method for determining equipment problems and problem solving measures includes:

The equipment problems include: instrument failure and equipment abnormality;

The instrument failure includes: real-time quality judgment on the transmission data of the temperature sensors T1-T7, the real-time circulation total flow FT1, and the real-time pressure P1 measured in the pipeline. When there is a disconnection and/or a short circuit and/or the rate of rise and fall is too fast, it indicates an instrument failure.

Further, the abnormality of the device includes:

The device cannot complete the command action within the specified time;

The device outputs a fault signal;

The device cannot perform automatic operations.

Further, the method for determining equipment problems and problem-solving measures also includes:

Measures to address the problem include:

For instrument failure or equipment abnormality, it is impossible to immediately stop the calculation, reset the calculation cycle, and clear the calculation-related data values when the heat dissipation control is not possible. At the same time, the man-machine interface will issue a calculation stop alarm and indicate the reason for the stop;

When equipment abnormalities make the control heat release scheme unable to be executed, stop controlling the corresponding equipment to continue to operate, but only maintain the last running state of the equipment, clear the subsequent action scheme, and the man-machine interface sends a control stop alarm to indicate the reason for the stop.

Further, the method for controlling the temperature of the cooling medium by controlling according to the heat release control scheme and the abnormal treatment measures of the equipment includes:

Preset required parameters S, α, X, Y;

Control the frequency conversion motor M1 to run according to the set total flow SPft1;

First check whether the instrumentation equipment is abnormal, and execute the corresponding treatment measures when it is abnormal, otherwise determine whether the cycle is over, if it is not over, return to the instrumentation equipment, if it is over, store the data and obtain the heat release control plan;

Control the corresponding equipment according to the heat release control scheme to control the temperature of the cooling medium.

In the third aspect, the present invention also provides a control system using the above method for regulating the temperature of the cooling medium used in the circulating cooling system, including:

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

Action formulation module to identify equipment problems and problem-handling actions; and

The execution module controls the temperature of the cooling medium according to the heat release control scheme and the abnormal treatment measures of the equipment.

In the fourth aspect, the present invention also provides a temperature control device that adopts the above cooling medium temperature control method for a circulating cooling system, including:

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 adapted to control the corresponding three-way regulating valve V1, the frequency conversion motor M1 and the frequency conversion motor M2 according to the heat release control scheme, so as to control the temperature of the cooling medium.

The beneficial effect of the present invention is that, the present invention obtains the exothermic control scheme in the circulating cooling system according to the heat release heat detection method of the cooling medium in the circulating cooling system; determines the equipment problem and the problem treatment measures; and controls according to the exothermic control scheme and the abnormal treatment measures of the equipment to control the temperature of the cooling medium, realizes rapid feedback, regularly predicts the change of water temperature, rapidly raises and lowers the temperature, and avoids the error of the sensor to accurately control the temperature.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and appended drawings.

In order to make the above-mentioned objects, features and advantages of the present invention more comprehensible, preferred embodiments will be described in detail below together with the accompanying drawings.

Description of drawings

In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the accompanying drawings that need to be used in the description of the specific embodiments or prior art. Obviously, the accompanying drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings without creative work.

Fig. 1 is the flow chart of the cooling medium temperature control method for the circulating cooling system involved in the present invention;

Fig. 2 is a schematic diagram of equipment involved in the present invention;

Fig. 3 is a control logic diagram involved in the present invention.

Detailed ways

In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Apparently, the described embodiments are part of the embodiments of the present invention, but not all of them. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

This embodiment provides a method for detecting the heat release of cooling medium in a circulating cooling system, which is characterized in that it includes: obtaining the absorbed heat energy at the place where the cooling water flows through the incineration zone:

Among them, E1 is the heat energy absorbed by the cooling water flowing through the incineration area in one calculation cycle; msn is the mass of desalinated water flowing through at the nth second; cpn is the specific heat capacity of the desalinated water at constant pressure at the nth second; T1n is the real-time desalinated water temperature measured by the T1 temperature sensor at the nth second; T6n is the real-time desalinated water temperature measured by the T6 temperature sensor at the nth second;

Among them, Q2 is the first basic heat dissipation; T1n is the real-time desalinated water temperature measured by the T1 temperature sensor at the nth second; T2n is the real-time desalinated water temperature measured by the T2 temperature sensor at the nth second; E2 flows through the second heat exchanger to release heat in one calculation cycle; obtain the heat released through the chute area:

Among them, Q7 is the second basic heat dissipation; T7n is the real-time desalinated water temperature measured by the T7 temperature sensor at the nth second; E7 is the heat release in the chute area in one operation cycle; obtain the heat energy required to maintain SPt1 in one operation cycle:

Among them, SPt1 is always a fixed value K in 1-s seconds; ESP needs to absorb heat energy for one cycle when maintaining the K temperature; the heat energy difference is ΔE, then ΔE=ESP-E1; ΔE=ESP-E1=-(E6+E2+E7);

E6=E1-ESP-E2-E7; Wherein, 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); where, T1S is the real-time desalinated water temperature measured by the T1 temperature sensor at the last moment of the end of a calculation cycle; α is the gain coefficient.

As shown in Figures 1-3, this embodiment also provides a cooling medium temperature control method for a circulating cooling system, including: obtaining a heat release control scheme in the circulating cooling system according to the heat release heat detection method of the cooling medium in the circulating cooling system; determining equipment problems and problem handling measures; and performing control according to the heat release control scheme and equipment abnormality handling measures to control the temperature of the cooling medium, realizing rapid feedback, regular prediction of water temperature changes, rapid heating and cooling, and accurate temperature control to avoid sensor errors.

In this embodiment, the specific equipment structure involved in the cooling medium temperature control method used in the circulating cooling system can be: based on a certain control system platform (PLC, DCS, etc.), it is necessary to convert the algorithm in the control method into an execution code and a human-machine interface. At the same time, the control system needs to collect on-site real-time data, use the built-in algorithm for real-time calculation, and then output the result to dynamically control the field 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 save energy and reduce consumption as much as possible by minimizing the control of high-power motor equipment; the circulation system is closed, so the overall pipeline is filled with liquid and has a high pressure, as shown in Figure 2. The equipment is connected to the circulation pipeline to form a complete circulation system, and the arrow in the figure indicates the flow direction of the liquid; the incineration area refers to the area where waste is incinerated on the mechanical grate. with uncertainty. The second heat exchanger (heat exchanger 2) refers to the heat exchange equipment (belonging to the partition wall heat exchanger) through the refrigerant (usually air), allowing the refrigerant to take away part of the heat, which is an exothermic process. Here the refrigerant flow rate is fixed. The chute area is the area through which cooling water flows to dissipate heat, which is an exothermic process. The first heat exchanger (heat exchanger 1) refers to the heat exchange equipment (belonging to the partition wall heat exchanger) through the refrigerant (usually air). Among them, the flow rate of the refrigerant is adjusted by frequency conversion, so that the amount of heat taken away can be controlled, which is also different from the second heat exchanger. M1 and M2 are variable frequency motors with variable frequency speed regulation. M1 is the motor used to drive the circulating pump to provide the kinetic energy for the circulation of desalinated water. M2 is the motor for adjusting the amount of refrigerant in the first heat exchanger. Both devices are connected to the control system. V1 is a three-way regulating valve. In the figure, a shows water inlet, and b and c are water outlets. The inflow is equal to the total outflow, which follows the principle of FT(a)=FT(b)+FT(c). Adjusting the opening of the valve can increase or decrease the flow at b, and at the same time, the flow at c decreases or increases accordingly. The larger the opening of the V1 valve, the greater the flow at b. Access of the equipment to the control system. P1 is the real-time pressure measured in the pipeline, and the data is connected to the control system. T1~T7 are the real-time desalinated water temperature measured by temperature sensors at each point, and the data is connected to the control system. FT1 is the real-time circulation total flow (instantaneous flow at a certain moment), and this data is connected to the control system.

In this embodiment, according to the Bernoulli equation, because it is a closed system, most of the mechanical energy provided by M1 is converted into lost internal energy, and finally converted into heat energy. Since there are many places for heat dissipation in the equipment (the surface area of the pipeline is large), it is found in actual tests that the mechanical energy of the motor M1 has almost no effect on the temperature of the desalinated water. Therefore, the influence of the mechanical energy of M1 on the water temperature control is not considered in the control algorithm in the control method described in this embodiment. At the same time, according to the requirements of the production process, it is necessary to ensure that the T1 temperature (the outlet water temperature of the incineration zone in Fig. 2, hereinafter all equipment with numbers is equal to the equipment with the same number in Fig. 2) is constant around a certain temperature value. On the basis of satisfying this premise, it is best to automatically control the temperature with the minimum energy consumption. The control algorithms described in the present invention are all developed around this goal. First of all, it is necessary to set the ideal control value of T1 temperature K, and K is the determined process production temperature, which is represented by SPt1 here, that is, SPt1=K. At the same time, FT1 presets an ideal total flow value U, represented by SPft1 here, that is, SPft1=U. These two are relatively reasonable parameters set by process + equipment + test. Then set the operation period to s seconds (s is a specific value, which can be modified in the man-machine interface). This cycle is also the time period for the control system to automatically calculate the heat.

In this embodiment, the heat release control scheme for obtaining the circulating cooling system is: according to the calculation formula of the heat conduction theory, the heat energy absorbed by the cooling water flowing through the incineration zone is obtained:

Among them, E1 is the heat energy absorbed by the cooling water flowing through the incineration area in one calculation cycle, and the unit is KJ; msn is the mass of desalted water flowing through in the nth second (obtained by multiplying the real-time flow FT1 by the desalinated water density ρ); cpn is the specific heat capacity of the desalinated water at constant pressure at the nth second, and the specific value can be obtained by checking the reference book for cpn (the pressure is measured by P1, and the pressure is very stable during normal operation); T1n is the real-time desalinated water temperature measured by the T1 temperature sensor at the nth second; The real-time desalinated water temperature measured by the temperature sensor; s is the set operation cycle; the above formula is to add the heat power of each second in 1 to s seconds to obtain the sum of the heat absorbed by the desalinated water in one operation cycle; specifically, if the first second data FT1=220m3/h, P1=78Kpa, ρ=1000kg/m3, cpn=0.98kJ/kg, T1=77℃, T6=71℃, the heat energy Q1 in the first second ₁＝220/3600*1000*0.98*(77-71)＝359.3(kJ/s); 2nd second data FT1＝223m3/h, P1＝78Kpa, ρ＝1000kg/m3, cpn＝0.98kJ/kg, T1＝78℃, T6＝71℃, heat energy Q1 in the 2nd second ₂＝223/3600*1000*0.98*(78-71)＝424.9(kJ/s), if S is 2 seconds, then the total heat absorption is E1＝Q1 ₁+Q1 ₂=784.2KJ.

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

Among them, Q2 is the first basic heat dissipation (can be regarded as a fixed constant); T1n is the real-time desalinated water temperature measured by the T1 temperature sensor at the nth second; T2n is the real-time desalinated water temperature measured by the T2 temperature sensor at the nth second; E2 is the heat released through the second heat exchanger in one operation cycle; these parameters have been connected in the control system, and the heat released by the second heat exchanger in one operation cycle can be easily calculated by using the formula to calculate the heat addition per second;

Since the chute is a mature industrial product, the heat dissipation area and heat transfer coefficient are all 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

Among them, Q7 is the second basic heat dissipation; T7n is the real-time desalinated water temperature measured by the T7 temperature sensor at the nth second; E7 is the heat release in the chute area within one calculation cycle;

The circulatory system is regarded as an independent thermodynamic system, which conforms to the law of conservation of heat energy. Therefore, to keep the T1 temperature constant, the heat release and heat absorption in the system need to reach a balance within a period of time. The heat energy required to maintain SPt1 is calculated within one calculation cycle, and the heat energy required to maintain SPt1 is calculated within one calculation cycle by using the heat conduction formula:

Among them, SPt1 is always a fixed value K from 1 to s seconds; ESP needs to absorb heat energy in one cycle to maintain K temperature; E1 is regarded as the actual heat absorbed;

The thermal energy difference is ΔE, then ΔE=ESP-E1, the difference of thermal energy needed to maintain a constant temperature K;

ΔE=ESP-E1=-(E6+E2+E7);

E6＝E1-ESP-E2-E7 (the values in this formula are all positive numbers, if E6 is calculated as a positive number, heat release is required, and if a negative number appears, heat release is not required);

Wherein, E6 is the heat release value of the first heat exchanger, and the heat release value in one cycle from T3 to T6. It should be noted that E1, ESP, E2, and E7 are all calculated synchronously at the last moment of a certain calculation cycle, while the value of E6 must be known after the end of the cycle, and then start to control the first heat exchanger in the next cycle to complete the calculation of heat. At the same time, E1, ESP, E2, and E7 are calculated in the next cycle. After the end, the next cycle starts to control the first heat exchanger to release a new heat value, and so on. Therefore, the release of E6 is always one cycle slower (that is, E6 releases the excess heat generated in the previous cycle). Because the amount of desalinated water in the entire circulation system is large, and the specific heat capacity of desalinated water is large, the circulation system is like a large storage tank.

There is also a certain error in the measured value of the instrument. If the operation time is long, the accumulated error will also cause the temperature T1 to gradually exceed the standard. Therefore, a gain coefficient α needs to be introduced here. This gain coefficient can be set on the man-machine interface. The final calculated E6 and the actual temperature difference gain product is the final heat release value required by heat exchanger 1, and the final heat release value of the first heat exchanger is obtained:

E6'=|[1+α(T1S-SPt1)]|(E1-ESP-E2-E7);

Among them, T1S is the real-time desalinated water temperature measured by the T1 temperature sensor at the last moment of the end of a calculation cycle; α is the gain coefficient; E6' will not get the result until the end of a calculation cycle; when the cumulative error causes T1 to rise larger, the heat release will be more in the next cycle, so this is also a powerful measure to ensure the stability of T1 temperature.

In this embodiment, the control heat release scheme in the acquisition of the circulating cooling system can also be: different E6' values must correspond to different control strategies, and at the same time, the energy saving effect must also be taken into account, and the equipment must not be too large to cause system oscillation; when the heat exchanger 1 pipeline b is fully closed, the heat dissipation when the whole desalted water flows to the c branch is Ec (here Ec is a positive number, even if the heat exchanger 1 is not activated, the pipeline has a certain heat dissipation effect). Ec is the minimum heat release, which can be regarded as a fixed constant. When E6'<=Ec, adjust the opening of V1 to 0% (see the description of V1 above), stop the M2 motor, and generally set the action within 5 seconds. It has been measured that when the entire desalted water flows to the b branch and the heat dissipation of the motor M2 of the heat exchanger 1 is 100% of the operating frequency, the heat dissipation is Eb (here Eb is a positive number), and Eb is the maximum heat release, which can be regarded as a fixed constant. When E6'>=Eb, the opening of V1 is adjusted to 100%, and the operating frequency of the M2 motor is 100% of the rated frequency. Generally, the action is in place within 5 seconds.

When Ec<E6'<Eb, first divide E6' by the preset heat release time J (J<S, which can be modified on the man-machine interface) to obtain the required heat release per second. The data on the relationship between desalted water flow-refrigerant volume-heat release of heat exchanger 1 is obtained in the early stage. Heat exchanger 1 is also a mature industrial product. The broken line table of flow-refrigerant volume-heat release given by the equipment manufacturer is corrected by the actual test data. In some cases, the flow rate and the specific value of the refrigerant flow rate can be obtained through the table look-up method; in addition, according to the inherent flow characteristics of V1 and the actual measurement on site, the V1 opening and the b branch flow curve table are also obtained, and then the curve table is also built into the control system, and the M2 frequency and refrigerant flow rate curve table can also be obtained. In this way, the algorithm can control the heat release according to the principle of first adjusting the valve V1 and then adjusting the valve M2 through the built-in curve table after each output value. Adjust the flow through the heat exchanger 1 (branch b) by first adjusting the opening of V1, and stop M2; when V1 cannot be adjusted (that is, the 100% opening cannot be adjusted), start the M2 motor, and increase the amount of refrigerant through frequency conversion; if the subsequent heat dissipation becomes smaller and does not need the operation of the M2 motor, stop the M2 motor; and so on.

When E6'<=Ec lasts for a long time, the system lacks heat for a long time and the overall temperature drops, which does not meet the process requirements. Therefore, it is necessary to set the lower limit of T1 temperature T1L=X (X can be modified on the man-machine interface). Action; when E6'>=Eb lasts for a long time, the long-term heat accumulation of the system will cause the overall temperature to rise. It is necessary to set the upper limit of T1 temperature T1H=Y (Y can be modified in the man-machine interface). When T1>Y, increase the total flow FT1 to 130% of the original SPft1 (ie 1.3U). Only when the temperature of T1 returns to the range of 1.05X<=T1<=0.95Y in a later period, the flow will return to the U value, and the alarm information will be automatically reset, otherwise, it will continue to run according to the total flow FT1 after decreasing\increasing. If the heat is too small, it is fully closed, and if the heat is too large, it is fully opened. The heat is checked in the middle to get the medium flow rate. Only the valve is opened first, and the motor is turned on when the motor is used. If T1 reaches the limit, reduce\increase the total flow before executing. The cooling water will not return to the preset value until T1 returns to the normal range; the precise control performance of the cooling equipment is obtained through the look-up table method and empirical formula, and the operation of the equipment is controlled according to the optimized scheme to achieve a more energy-saving effect than before; the gain coefficient and setting range are used to automatically and accurately control the fluctuation of the water temperature within a small range.

In this embodiment, the method for determining equipment problems and problem-solving measures includes: some equipment problems occur during actual operation, such as faults such as gear jamming and low voltage, and if operators ignore them, production accidents will occur. Therefore, automatic processing measures in this regard must be added to the control algorithm, otherwise the equipment will cause production accidents due to misoperation, or will not affect the next step of the algorithm. The equipment problems include: instrument failure and equipment abnormality; It means that once the instrument fails, the algorithm will keep the instrument failure information (including the instrument code and the type of failure, etc.), until it is repaired and the failure information is manually reset to return to normal.

In this embodiment, the abnormality of the equipment includes: the equipment that needs to be controlled on site cannot complete the command action within the specified time due to jamming, overloading and other reasons. If an instruction is sent to V1 to open to 100%, after a period of time, the feedback signal indicates that V1 is only opened to 80%, which means that some reason causes V1 to not open properly or the action is extremely slow, which must be abnormal. At this time, it can be considered that V1 is abnormal. The equipment that needs to be controlled on site outputs fault signals (motor overcurrent, low voltage, etc.) to the control system. For example, during the operation of V1, it suddenly outputs a valve over-torque signal to the control system, which indicates that V1 has a mechanical failure. For some reason, the equipment that needs to be controlled on site does not allow the automatic operation of the control system. For example, if the V1 equipment is inspected on site, the maintenance personnel will select the position of the control source button as "local", which indicates that the V1 valve cannot be remotely controlled. At this time, we also classify this situation as an abnormal situation in V1. The concept of equipment returning to normal means that once an abnormality occurs, the abnormal information (including the code name of the equipment and the type of abnormality, etc.) will be kept in the control algorithm until it is repaired and the information is manually reset, so that it can be regarded as returning to normal. In the control algorithm, if you want to check whether the instrument or equipment is abnormal, you only need to check the relevant fault or abnormal information. Similarly, if you want to check whether the instrument or equipment is back to normal, you only need to check whether the relevant state is back to normal.

In this embodiment, the method for determining equipment problems and problem-solving measures further includes: the problem-handling measures include: for instrument failures or equipment abnormalities, even if the control system calculates the results, it will not have any effect on heat dissipation control, so the processing measures are also executed for the calculation cycle, specifically stop the calculation immediately, reset the calculation cycle, and clear calculation-related data values. At the same time, the man-machine interface sends a calculation stop alarm and specifies the reason for the stop. To facilitate maintenance personnel to quickly repair. For equipment abnormalities, the control heat release scheme will be affected. Therefore, the processing measures are carried out for the control equipment action, specifically to stop the control of the corresponding equipment to continue to operate, but only maintain the last running state of the equipment, clear the subsequent action scheme, and at the same time the man-machine interface sends a control stop alarm to indicate the reason for the stop. To facilitate maintenance personnel to quickly repair. When an exception occurs, it is always necessary to manually solve the on-site problem. At this time, the action of the heat dissipation equipment of the whole system does not change, although it will not affect the T1 temperature for a short time. However, the operating personnel still need to repair the fault as soon as possible. If it has been repaired, the operating personnel will reset the alarm, and the control system will re-run the calculation cycle. If it cannot be repaired, it will be automatically transferred to manual control.

Specifically, an example is now given: If K=75°C, S=30 seconds, α=0.1, U=300m3/h, X=65°C, Y=92°C, J=29 seconds, Ec=400KJ, Eb=4300KJ;

At the end of the nth computing cycle, E1=10000KJ, ESP=7000KJ, E2=1000KJ, E7=800KJ, T1=85°C, then E6'=|[1+0.1x(85-75)]|(10000-7000-1000-800)=2400KJ. Then heat exchanger 1 should dissipate heat 2400/29=82.8KJ per second. At this time, the n+1th calculation cycle starts. At the same time, the control system obtains the flow rate of heat exchanger 1 through table lookup to be 214m3/h, and the amount of refrigerant is 0. The best solution for this flow rate is V1 opening 84%, M2 not running, and under normal circumstances, it can be in place in a very short time. For a 30-second computing cycle, the response speed of the device has negligible impact on the cooling process. Get E1=11000KJ, ESP=7000KJ, E2=1000KJ, E7=800KJ, T1=85 DEG C then E6'=|[1+0.1x(83-75)]|(11000-7000-1000-800)=3960KJ at the end of the n+1 computing cycle. Here, the heat exchanger 1 should dissipate heat 136.5KJ per second, the flow through the heat exchanger 1 is 290m3/h, and the refrigerant volume is 30m3/h, then adjust the opening of V1 to 100%, the frequency of M2 to 15%, and so on.

If there is an extreme situation, at the end of m cycles, E1=5500KJ, ESP=7000KJ, E2=300KJ, E7=200KJ, T1=63℃, then E6'=|[1+0.1x(63-75)]|(5500-7000-300-200)=-400KJ, and it belongs to T1<X, then the corresponding V1 opening is 0%, M2 is not running, the flow rate is reduced to 210m3/h, the interface displays a low-temperature combustion alarm, and the calculated flow base value becomes 210m3/h in m+1 cycles. At the end of p cycles E1=13000KJ, ESP=7000KJ, E2=2000KJ, E7=1200KJ, T1=93℃, then E6'=|[1+0.1x(93-75)]|(13000-7000-2000-1200)=7840KJ, T1>Y corresponds to V1 opening 100%, M2 frequency 100% operation, the flow rate rises to 390m3/h, and the interface displays a high-temperature combustion alarm. If T1=85°C after n cycles later, it is 1.05X<=T1<=0.95Y, and the total flow rate is reduced to 300m3/h.

If in the rth cycle when T1 is suddenly disconnected and the temperature suddenly rises to 400°C, the algorithm detects that the meter is faulty, it will stop according to the calculation, clear the relevant calculated values, and the interface will display the T1 fault alarm processing measures to execute. If the fault is not recovered, the operation cycle will not go on, even after several cycles, V1 and M2 will not perform any action and only maintain the original state.

In this embodiment, the method for controlling the temperature of the cooling medium by controlling according to the exothermic control scheme and equipment abnormality treatment measures includes: preset required parameters S, α, X, Y; control the frequency conversion motor M1 to operate according to the set total flow rate SPft1; first detect whether the instrumentation equipment is abnormal, and execute corresponding processing measures when it is abnormal; otherwise, determine whether the cycle is over.

Specifically, the required parameters S, α, X, Y, etc. are preset. Starting the system operation refers to controlling the motor M1 to operate according to the set total flow rate U. The operating frequency of the motor M1 is obtained by building the M1 frequency-flow curve in the control system and querying the curve. In addition, the PID function of the control system is used to fine-tune the M1 frequency so that the system flow rate tends to stabilize at U quickly. The frequency-flow characteristic curve is an inherent attribute of the water pump and is given by the equipment manufacturer. Next, start the cycle operation, first check whether the instrumentation equipment is abnormal, here are two directions, one is to execute the processing measures when there is an abnormality, and then delay to wait for the abnormality to be repaired to reset the alarm. It should be noted that at this time, the entire algorithm keeps polling whether to repair the fault, and does not perform any other calculations. If it is repaired in a short time, it will return to restart the operation. If it cannot be repaired within 30 minutes, the control system will stop the operation of the algorithm and transfer to manual control.

The second direction is to execute the next operation if there is no abnormality, and then determine whether the cycle is over, if not, return to check the instrumentation equipment, and perform the next calculation, and so on. If it's over then store the data and get the control exotherm scheme.

Next, the next operation cycle starts. Here, 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 in the heat release control plan. First, it detects whether the corresponding equipment that needs to be operated is abnormal. If there is no abnormality, execute the next control action, because the control equipment is not in place in one step, so after each execution, it is necessary to determine whether the corresponding plan has been executed. What needs to be explained is: there is no next step after the execution of the plan here, and a new round of control plan can only be executed after the next cycle is started, so that as long as there is no abnormal situation, the automatic control can continue. Once only the instrument failure occurs, the periodic operation must be stopped, but the control scheme will not stop executing all the actions. If there is an equipment failure, the periodic operation and the control equipment will be stopped at the same time. The purpose of this is to ensure the safety of the equipment and reflect the flexibility of the algorithm. One-button start-stop algorithm operation, easy to operate. The implementation cost is low, and only a small number of instrument valves are involved in the control. The main work of implementation is programming, and there is basically no cost. High safety and reliability. When the algorithm is executed, the device status is queried to prevent personal accidents caused by on-site misoperation. When automatic control cannot be performed for some reason, it will automatically alarm and remind personnel to manually control. The control algorithm adopts hold-type information records, which is convenient for in-depth research such as root tracing and data analysis. The control algorithm architecture is modular, the logic is simple, and the thinking is clear. It is also very 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 operates once in a cycle, and sometimes even does not need to operate. This solves the problem that the previous frequent operation of the control equipment caused the aging of the equipment and increased the failure rate. In addition, the algorithm can also intelligently calculate the control commands without relying on the feedback signal to act on the equipment, preventing the interference of the feedback signal from causing the equipment to control disorderly actions, and the control is in place at one time, preventing eddy currents or surges in the closed system from damaging the equipment, which has great benefits for equipment protection; automatic operation, automatic calculation, automatic monitoring of data, fast response, no dead ends, improve production efficiency, reduce labor intensity, and are welcomed by operators.

This embodiment also provides a control system that adopts a cooling medium temperature control method for a circulating cooling system, including: a scheme formulation module to obtain a heat release control scheme in a circulating cooling system; a measure formulation module to determine equipment problems and problem handling measures; and an execution module to perform control according to the heat release control scheme and equipment abnormality handling measures to control the temperature of the cooling medium.

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

This embodiment also provides a temperature control device adopting a cooling medium temperature control method for a circulating cooling system, including: 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, variable frequency motor M1, and variable frequency motor M2 according to the heat release control scheme to control the temperature of the cooling medium.

In this embodiment, the control module adopts the cooling medium temperature control method used in the circulating cooling system to generate a heat release control scheme, etc., and adjusts the corresponding three-way valve V1, frequency conversion motor M1 and frequency conversion motor M2 to control the temperature of the cooling medium.

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

To sum up, the present invention obtains the exothermic control scheme in the circulating cooling system through the method for detecting the exothermic heat of the cooling medium in the circulating cooling system; determines the equipment problem and the treatment measures for the problem; and controls according to the exothermic control scheme and the abnormal treatment measures of the equipment to control the temperature of the cooling medium, realizes rapid feedback, predicts the change of water temperature regularly, rapidly raises and lowers the temperature, and avoids the error of the sensor to accurately control the temperature.

In the several embodiments provided in this application, it should be understood that the disclosed devices and methods may also be implemented in other ways. The device embodiments described above are only illustrative. For example, the flowcharts and block diagrams in the accompanying drawings show the architecture, functions and operations of possible implementations of devices, methods and computer program products according to multiple embodiments of the present invention. In this regard, each block in the flowchart or block diagram may represent a module, program segment, or a portion of code that includes one or more executable instructions for implementing specified logical functions. It should also be noted that, in some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks in succession may, in fact, be executed substantially concurrently, or they may sometimes be executed in the reverse order, depending upon the functionality involved. It should also be noted that each block in the block diagrams and/or flowchart illustrations, and combinations of blocks in the block diagrams and/or flowchart illustrations, can be implemented by special purpose hardware-based systems that perform the specified functions or actions, or by combinations of special purpose hardware and computer instructions.

In addition, each functional module in each embodiment of the present invention can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

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 such an understanding, the technical solution of the present invention can be embodied in the form of a software product in essence or the part that contributes to the prior art or a part of the technical solution. The computer software product is stored in a storage medium and includes several instructions to make a computer device (which can be a personal computer, a server, or a network device, etc.) execute all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: various media that can store program codes such as U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), magnetic disk or optical disk.

Inspired by the above-mentioned ideal embodiment according to the present invention, through the above-mentioned description content, relevant workers can make various changes and modifications within the scope of not departing from the technical idea of the present invention. The technical scope of the present invention is not limited to the content in the specification, but must be determined according to the scope of the claims.

Claims (9)

1. A method for detecting heat release of a cooling medium in a circulating cooling system, characterized in that it includes:

   Capturing the absorbed thermal energy where the cooling water flows through the incineration zone:

   

   Among them, E1 is the heat energy absorbed by the cooling water flowing through the incineration area in one operation cycle; msn is the mass of desalinated water flowing through in the nth second; cpn is the specific heat capacity of the desalinated water at constant pressure at the nth second; T1n is the real-time desalinated water temperature measured by the T1 temperature sensor at the nth second; T6n is the real-time desalinated water temperature measured by the T6 temperature sensor at the nth second; s is the set calculation cycle;

   Obtain the heat release through the second heat exchanger:

   

   Among them, Q2 is the first basic heat dissipation; T1n is the real-time desalinated water temperature measured by the T1 temperature sensor at the nth second; T2n is the real-time desalinated water temperature measured by the T2 temperature sensor at the nth second; E2 flows through the second heat exchanger to release heat in one calculation cycle;

   Obtain the heat release through the chute zone:

   

   Among them, Q7 is the second basic heat dissipation; T7n is the real-time desalinated water temperature measured by the T7 temperature sensor at the nth second; E7 is the heat release in the chute area within one calculation cycle;

   Obtain the heat energy required to maintain SPt1 in one calculation cycle:

   

   Among them, SPt1 is always a fixed value K from 1 to s seconds; ESP needs to absorb heat energy in one cycle to maintain K temperature;

   The thermal energy difference is ΔE, then ΔE=ESP-E1;

   ΔE=ESP-E1=-(E6+E2+E7);

   E6=E1-ESP-E2-E7;

   Wherein, 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);

   Among them, T1S is the real-time desalinated water temperature measured by the T1 temperature sensor at the last moment of the end of a calculation cycle; α is the gain coefficient.
2. A cooling medium temperature control method for a circulating cooling system, characterized in that it includes

   The method for detecting heat release of cooling medium in a circulating cooling system as claimed in claim 1 obtains a scheme for controlling heat release in a circulating cooling system;

   Identify equipment problems and problem-solving actions; and

   Control according to the heat release control plan and equipment abnormal treatment measures to control the temperature of the cooling medium.
3. The cooling medium temperature control method for circulating cooling system as claimed in claim 2, characterized in that,

   The control exothermic scheme in the described acquisition circulating cooling system is:

   When the first heat exchanger pipeline b is fully closed, the heat dissipation when the entire desalted water flows to the c branch is Ec. When E6'<=Ec, adjust the opening of the three-way regulating valve V1 to 0%, and stop the frequency conversion motor M2;

   When the entire desalinated water flows to the b branch and the heat dissipation is Eb when the frequency conversion motor M2 of the first heat exchanger operates at 100%, when E6'>=Eb, adjust the opening of the three-way regulating valve V1 to 100%, and the frequency conversion motor M2 operates at 100% of the rated frequency;

   When Ec<E6'<Eb, first divide E6' by the preset heat release time J to obtain the required heat release per second, adjust the flow through the first heat exchanger according to the opening of the three-way regulating valve V1, and stop M2; when V1 cannot be adjusted, start M2, and increase the amount of refrigerant through frequency conversion; when the heat dissipation becomes smaller and does not need M2 to operate, then stop M2;

   When the E6 <= EC continues the preset time, set the T1 temperature lower limit T1L = x, when T1 <x, reduce the total current FT1 to 70 % of the original SPFT1; when E6 ＇> = EB continues the preset time, set the T1 temperature upper limit T1H = Y, increase the total flow FT1 to 130 % of the original SPFT1; During the period, the T1 temperature returned to 1.05x <= t1 <= 0.95y, and the flow was restored to SPFT1.
4. The cooling medium temperature regulation method for circulating cooling system as claimed in claim 3, is characterized in that,

   The method for determining equipment problems and problem handling measures includes:

   The equipment problems include: instrument failure and equipment abnormality;

   The instrument failure includes: real-time quality judgment on the transmission data of the temperature sensors T1-T7, the real-time circulation total flow FT1, and the real-time pressure P1 measured in the pipeline. When there is a disconnection and/or a short circuit and/or the rate of rise and fall is too fast, it indicates an instrument failure.
5. The cooling medium temperature control method for circulating cooling system as claimed in claim 4, characterized in that,

   The device anomalies include:

   The device cannot complete the command action within the specified time;

   The device outputs a fault signal;

   The device cannot perform automatic operations.
6. The cooling medium temperature control method for circulating cooling system as claimed in claim 5, characterized in that,

   The method for determining equipment problems and problem handling measures also includes:

   Measures to address the problem include:

   For instrument failure or equipment abnormality, it is impossible to immediately stop the calculation, reset the calculation cycle, and clear the calculation-related data values when the heat dissipation control is not possible. At the same time, the man-machine interface will issue a calculation stop alarm and indicate the reason for the stop;

   When equipment abnormalities make the control heat release scheme unable to be executed, stop controlling the corresponding equipment to continue to operate, but only maintain the last running state of the equipment, clear the subsequent action scheme, and the man-machine interface sends a control stop alarm to indicate the reason for the stop.
7. The cooling medium temperature control method for circulating cooling system as claimed in claim 6, characterized in that,

   The method for controlling the temperature of the cooling medium by controlling according to the heat release control scheme and the equipment abnormality treatment measures includes:

   Preset required parameters S, α, X, Y;

   Control the frequency conversion motor M1 to run according to the set total flow SPft1;

   First check whether the instrumentation equipment is abnormal, and execute the corresponding treatment measures when it is abnormal, otherwise determine whether the cycle is over, if it is not over, return to the instrumentation equipment, if it is over, store the data and obtain the heat release control plan;

   Control the corresponding equipment according to the heat release control scheme to control the temperature of the cooling medium.
8. A control system using the cooling medium temperature regulation method for a circulating cooling system according to any one of claims 2-7, characterized in that it comprises:

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

   Action formulation module to identify equipment problems and problem-handling actions; and

   The execution module controls the temperature of the cooling medium according to the heat release control scheme and the abnormal treatment measures of the equipment.
9. A temperature control device using the cooling medium temperature control method for a circulating cooling system according to any one of claims 2-7, characterized in that it comprises:

   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 adapted to control the corresponding three-way regulating valve V1, the frequency conversion motor M1 and the frequency conversion motor M2 according to the heat release control scheme, so as to control the temperature of the cooling medium.

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