Control method and control system for temperature regulating valve of non-regenerative heat exchanger of nuclear power station

Abstract

The invention relates to the technical field of nuclear power station temperature regulating valve control, in particular to a nuclear power station non-regenerative heat exchanger temperature regulating valve control method and system, and the method comprises the steps: 1, determining the highest temperature T1 and the lowest temperature T2 of cooling water of a cooling water heat exchanger; 2, determining normal operation of a heat exchange unit of the non-regenerative heat exchanger; 3, when the cooling water temperature of the cooling water heat exchanger is reduced from the highest temperature to the lowest temperature, the temperature and flow change of the cooling water of the non-regenerative heat exchanger is measured; and 4, setting a temperature comparison value, a critical set value and a temperature set value of the control unit. According to the method, the temperature comparison value, the critical set value and the temperature set value of the control unit are obtained through measurement, only control logic in a control system needs to be adjusted, equipment does not need to be additionally arranged on a process system, and the use cost is low.

Description

Technical Field

[0001] This invention relates to the field of temperature regulating valve control technology for nuclear power plants, and in particular to a method and control system for controlling the temperature regulating valve of a non-regenerative heat exchanger in a nuclear power plant. Background Technology

[0002] Nuclear power plants have numerous regulating valves for temperature control. These valves are typically installed on the cooling water side of heat exchangers, and by adjusting the cooling water flow rate, the outlet temperature of the heat exchanger is made to meet system requirements. Currently, the control logic for the cooling water regulating valves in heat exchangers mainly involves adding a temperature probe to the heat exchanger outlet on the side of the cooled medium. The temperature feedback from this probe controls the opening of the flow regulating valve on the cooling water side, thereby controlling the temperature of the cooled medium.

[0003] During nuclear power plant commissioning, it was discovered that the regulating valves of the non-regenerative heat exchanger in the reactor chemical and volume control system employed the aforementioned control logic. To enhance the heat exchanger's capacity, it was designed as a counter-flow heat exchanger. This type of heat exchanger has a drawback: a significant drop in cooling water temperature. Specifically, the cooling water inlet temperature is low, and since the inlet is in contact with the outlet of the cooled medium, the temperature of the cooled medium at the outlet further decreases. The temperature probe at the outlet of the cooled medium will then send new regulatory feedback, requesting a reduction in the opening of the cooling water flow regulating valve to increase the outlet temperature of the cooled medium. This phenomenon leads to a decrease in cooling water flow and a significant increase in cooling water temperature, causing thermal shock to downstream pipelines. Furthermore, the downstream cooling water pipeline temperatures are inconsistent between winter and summer operating conditions. In summer, when the cooling water temperature is high, the downstream pipeline temperature is close to the cooling water temperature; in winter, when the cooling water temperature is low, the downstream cooling water temperature rises significantly, even approaching the pipeline's design temperature. Meanwhile, since some downstream equipment of the heat exchanger is a resin bed, the resin bed will precipitate some chemical substances due to the temperature of the medium flowing through it, which will eventually lead to fluctuations in reactor power and affect the normal power generation of the nuclear power plant. Summary of the Invention

[0004] This invention provides a method and control system for controlling the temperature regulating valve of a non-regenerative heat exchanger in a nuclear power plant, which solves the problem of excessive temperature difference in non-regenerative heat exchange causing thermal shock to downstream pipelines in the prior art.

[0005] The technical solution of the present invention is as follows:

[0006] This invention proposes a method for controlling the temperature regulating valve of a non-regenerative heat exchanger in a nuclear power plant, the method comprising:

[0007] Step 1: Determine the highest cooling water temperature T1 and the lowest cooling water temperature T2 of the cooling water heat exchanger;

[0008] Step 2: Confirm that the non-regenerative heat exchanger heat exchange unit is operating normally;

[0009] Step 3: When the cooling water temperature of the cooling water heat exchanger drops from the highest temperature to the lowest temperature, measure the temperature and flow rate changes of the cooling water in the non-regenerative heat exchanger;

[0010] Step 3.1: When the temperature and flow rate of the cooled medium at the inlet B of the non-regenerative heat exchanger are at the design flow rate and temperature, control the cooling water temperature to decrease from the highest cooling water temperature T1 to the lowest temperature T2, that is, the reading of thermometer A decreases from the highest cooling water temperature to the lowest temperature. Record the changes in the opening of the regulating valve and the temperature values ​​of thermometers C and B; record that when thermometer A is at the highest temperature T1, the reading of thermometer C is T3 and the reading of thermometer B is T5; record that when thermometer A is at the lowest temperature T2, the reading of thermometer C is T4 and the reading of thermometer B is T6.

[0011] Step 3.2: Compare the difference between T5 and T6. If the difference between T5 and T6 exceeds 5°C, the temperature comparison value, critical setting value, and temperature setting value of the control unit need to be set.

[0012] Step 3.3: When temperature gauge A reaches the lowest temperature T1, gradually increase the opening of the regulating valve until the reading of temperature gauge C is lower than the maximum acceptable operating temperature of the pipeline, and record the reading of temperature gauge B9 as T7.

[0013] Step 3.4: Determine the maximum value T8 of the reading of temperature gauge A when temperature gauge C is at the highest acceptable operating temperature;

[0014] Step 4: Set the temperature comparison value, critical setpoint, and temperature setpoint of the control unit.

[0015] In some embodiments, step one includes:

[0016] Step 1.1: Obtain seawater temperature variation data for the nuclear power plant over a year;

[0017] Step 1.2: Introduce seawater at the same flow rate as designed into inlet A of the cooling water heat exchanger;

[0018] Step 1.3: Introduce equipment cooling water at the same flow rate as designed into the cooling water inlet A of the cooling water heat exchanger to confirm that the equipment cooling water system is operating normally;

[0019] Step 1.4: Determine the lowest temperature T1 of thermometer A on the equipment cooling water outlet pipeline as the seawater temperature drops to the lowest value of the seawater temperature in the year at the nuclear power plant.

[0020] Step 1.5: When the seawater temperature rises to the highest seawater temperature of the nuclear power plant in a year, determine the highest temperature T2 of the temperature gauge A on the equipment cooling water outlet 5 pipeline.

[0021] In some embodiments, step one specifically includes, during the commissioning phase of the nuclear power plant, obtaining the lowest and highest readings of the temperature gauge A of the nuclear power plant over one year by retrieving the parameter curves from the main control room.

[0022] In some embodiments, step two includes:

[0023] Step 2.1: Confirm that the cooling water flow rates at the cooling water inlet B and cooling water outlet B of the non-regenerative heat exchanger are normal;

[0024] Step 2.2: Confirm that the control valve is operating normally;

[0025] Step 2.3: Confirm that the flow rate of the cooled medium flowing into inlet B of the non-regenerative heat exchanger is normal;

[0026] In some embodiments, when the temperature value of temperature gauge C is determined to reach the highest acceptable operating temperature in step 3.4, the highest acceptable operating temperature is specifically the outlet cooling water temperature of the non-regenerative heat exchanger where the downstream pipeline is not subject to thermal shock.

[0027] In some embodiments, step four, setting the temperature comparison value, critical setpoint, and temperature setpoint of the control unit, specifically includes:

[0028] Step 4.1: Set the maximum value T8+2℃ of the temperature gauge A obtained in step 3.4 as the temperature comparison value of the comparator;

[0029] Step 4.2: Set the temperature setpoint as T7+5℃ obtained from the temperature gauge B in Step 3.3, and set the temperature gauge B reading T7 obtained from Step 3.3 as the critical setpoint.

[0030] In some embodiments, after step four, a rate ΔK is set for the selector. When the output of the comparator changes, the selector changes its output value through the rate ΔK.

[0031] This invention proposes a temperature regulating valve control system for a non-regenerative heat exchanger in a nuclear power plant. The system includes a cooling water heat exchange unit, a non-regenerative heat exchanger unit, and a control unit. The cooling water heat exchange unit includes a cooling water heat exchanger and a thermometer A. The cooling water heat exchanger has a seawater channel and a cooling water channel. The cooling water outlet A of the cooling water heat exchanger is connected to the non-regenerative heat exchanger unit via a pipeline. The thermometer A is installed on the pipeline connected to the cooling water outlet A of the cooling water heat exchanger. The non-regenerative heat exchanger unit includes a non-regenerative heat exchanger, a thermometer B, a thermometer C, and a regulating valve. The non-regenerative heat exchanger has a cooled medium channel and a cooling water channel. The cooling water inlet B of the non-regenerative heat exchanger is connected to the cooling water outlet A of the cooling water heat exchanger. The thermometer B is installed on the pipeline connected to the cooled medium channel outlet B of the non-regenerative heat exchanger. The regulating valve, thermometer C, and an ultrasonic flow meter are sequentially installed on the pipeline connected to the cooling water outlet B of the non-regenerative heat exchanger. The control unit is connected to the regulating valve, thermometer A, and thermometer B. The control unit controls the opening of the regulating valve to maintain a constant temperature value at thermometer B.

[0032] In some embodiments, the control unit includes a comparator, a selector, and a downstream comparator. The comparator is connected to a temperature gauge A, sets a temperature comparison value, and compares the temperature of temperature gauge A with the temperature comparison value. Based on the comparison result, the comparator controls the output value of the selector. The selector internally sets a critical setpoint and a temperature setpoint. Based on the instruction from the comparator, the selector selects to output either the critical setpoint or the temperature setpoint to the downstream comparator. The downstream comparator is connected to a temperature gauge B and a regulating valve, respectively. The downstream comparator compares the output value of the selector with the measured value of temperature gauge B, and controls the flow rate of the regulating valve to make the measured value of temperature gauge B consistent with the output value of the selector.

[0033] In some embodiments, when the measured value of thermometer A is greater than or equal to the temperature comparison value, the comparator of the control unit controls the selector to output a temperature setpoint, and the controller controls the flow rate of the regulating valve to make the measured value of thermometer B the same as the temperature setpoint; when the measured value of thermometer A is lower than the temperature comparison value, the comparator of the control unit controls the selector to output a critical setpoint, and the controller controls the flow rate of the regulating valve to make the measured value of thermometer B the same as the critical setpoint; when the selector adjusts the output value from the temperature setpoint to the critical setpoint or from the critical setpoint to the temperature setpoint, the adjustment rate of the selector is the setpoint change rate ΔK, and the value of ΔK does not exceed 1℃ / min.

[0034] The implementation of this invention has the following beneficial effects:

[0035] 1. This invention patent provides a method and control system for controlling the temperature regulating valve of a non-regenerative heat exchanger in a nuclear power plant. This method obtains the temperature comparison value, critical setpoint, and temperature setpoint of the control unit by measurement. Only the control logic in the control system needs to be adjusted, without adding additional equipment to the process system, resulting in low operating costs. This method is applicable to nuclear power plants at all stages. Even power plants that are already in commercial operation can be implemented through simple logic modifications during major overhauls.

[0036] 2. This invention provides a method and control system for controlling the temperature regulating valve of a non-regenerative heat exchanger in a nuclear power plant. This invention provides a more stable control logic for the cooling water temperature regulating valve of a non-regenerative heat exchanger in nuclear power plants where the seawater temperature difference is large in winter and summer. This logic can mitigate the thermal shock problem of the downstream cooling water pipeline caused by large changes in cooling water temperature. While mitigating the thermal shock of the cooling water pipeline, this method also takes into account the characteristics of the resin bed downstream of the heat exchanger, and will not cause the resin bed to accidentally precipitate or absorb boric acid in the coolant due to temperature changes, resulting in primary loop power fluctuations. This method has high reliability. Attached Figure Description

[0037] Figure 1 This is a flowchart illustrating the equipment cooling water heat exchange process of a temperature regulating valve control system for a non-regenerative heat exchanger in a nuclear power plant, as proposed in an embodiment of the present invention.

[0038] Figure 2 This invention provides a flow chart of the heat exchange process for a non-regenerative heat exchanger in a temperature regulating valve control system for a nuclear power plant.

[0039] Figure 3 This is a diagram of a temperature regulating valve control system for a non-regenerative heat exchanger in a nuclear power plant, as proposed in an embodiment of the present invention.

[0040] Explanation of reference numerals in the attached diagram: 1. Inlet A; 2. Outlet A; 3. Cooling water heat exchanger; 4. Cooling water inlet A; 5. Cooling water outlet A; 6. Thermometer A; 7. Inlet B; 8. Outlet B; 9. Thermometer B; 10. Cooling water inlet B; 11. Control valve; 12. Cooling water outlet B; 13. Non-regenerative heat exchanger; 14. Thermometer C; 15. Comparator; 16. Selector; 17. Downstream comparator. Detailed Implementation

[0041] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings and specific embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0042] like Figures 1 to 3 As shown, this invention proposes a regulating valve system for a non-regenerative heat exchanger in a nuclear power plant. The system includes an equipment cooling water heat exchange unit, a non-regenerative heat exchanger heat exchange unit, and a control unit. The equipment cooling water heat exchange unit includes a cooling water heat exchanger 3 and a temperature gauge A6. Seawater flows into and out of the inlet A1 and outlet A2 of the cooling water heat exchanger 3, respectively. Equipment cooling water flows into and out of the cooling water inlet A4 and outlet A5 of the cooling water heat exchanger 3, respectively. The cooling water inlet A4 of the cooling water heat exchanger 3 is connected to the cooling water system, and the temperature gauge A6 is installed on the pipeline connected to the cooling water outlet A5 of the cooling water heat exchanger 3.

[0043] The heat exchange unit of the non-regenerative heat exchanger 13 includes a non-regenerative heat exchanger 13, a thermometer B9, a thermometer C14, and a regulating valve 11. The cooling water inlet B10 of the non-regenerative heat exchanger 13 is connected to the cooling water outlet A5 of the cooling water heat exchanger 3. The cooled medium flows into and out of the inlet B7 and outlet B8 of the non-regenerative heat exchanger 13, respectively. The thermometer B9 is installed on the pipeline connected to the outlet B8. The regulating valve 11, the thermometer C14, and the ultrasonic flow meter are sequentially installed on the pipeline connected to the cooling water outlet B12 of the non-regenerative heat exchanger 13.

[0044] The control unit is connected to regulating valve 11, thermometer A6, and thermometer B9. The control unit controls the opening of regulating valve 11 to maintain a constant temperature value on thermometer B9. When the cooling water temperature after heat exchange with seawater is low in winter, and the temperature of the cooled medium at the outlet of the counter-flow heat exchanger decreases, the opening of regulating valve 11 is reduced in order to keep the temperature value on thermometer B9 constant.

[0045] The control unit includes a comparator 15, a selector 16, and a downstream comparator 17. The comparator 15 is connected to a temperature gauge A6. The comparator 15 sets a temperature comparison value and compares the temperature of the temperature gauge A6 with the temperature comparison value. Based on the comparison result, the comparator 15 controls the output value of the selector 16. The selector 16 internally sets a critical setpoint and a temperature setpoint. According to the instruction of the comparator 15, the selector 16 selects to output the critical setpoint or temperature setpoint to the downstream comparator 17. The downstream comparator 17 is connected to a temperature gauge B9 and a regulating valve 11. The downstream comparator 17 compares the critical setpoint or temperature setpoint output by the selector 16 with the measured value of the temperature gauge B9 and controls the flow rate of the regulating valve 11 so that the measured value of the temperature gauge B9 is consistent with the critical setpoint or temperature setpoint output by the selector 16.

[0046] When the measured value of temperature gauge A6 is greater than or equal to the temperature comparison value, comparator 15 of the control unit controls selector 16 to output the temperature setpoint, and the controller controls the flow rate of regulating valve 11 to make the measured value of temperature gauge B9 the same as the temperature setpoint. When the measured value of temperature gauge A6 is lower than the temperature comparison value, comparator 15 of the control unit controls selector 16 to output the critical setpoint, and the controller controls the flow rate of regulating valve 11 to make the measured value of temperature gauge B9 the same as the critical setpoint. When selector 16 adjusts the output value from the temperature setpoint to the critical setpoint or from the critical setpoint to the temperature setpoint, the adjustment rate of selector 16 is the setpoint change rate ΔK, which is used to prevent the temperature adjustment from being too fast and affecting the normal operation of the downstream resin bed of the heat exchanger.

[0047] This invention proposes a method for controlling the temperature regulating valve of a non-regenerative heat exchanger in a nuclear power plant, the method comprising:

[0048] Step 1: Determine the highest and lowest cooling water temperatures of cooling water heat exchanger 3.

[0049] Step 1.1: Obtain seawater temperature variation data for the nuclear power plant over a year;

[0050] Step 1.2: Seawater with the same flow rate as the design flow is introduced into the inlet A1 of the cooling water heat exchanger 3. The seawater is used to cool the equipment cooling water flowing into the heat exchanger 3 from the inlet 4.

[0051] Step 1.3: Introduce equipment cooling water at the same flow rate as designed into the cooling water inlet A4 of the cooling water heat exchanger 3 to confirm that the equipment cooling water system is operating normally;

[0052] Step 1.4: When the seawater temperature drops to the lowest seawater temperature in the nuclear power plant in a year, determine the lowest temperature of the temperature gauge A6 on the equipment cooling water outlet 5 pipeline. This temperature is the lowest cooling water temperature T1.

[0053] Step 1.5: When the seawater temperature rises to the highest seawater temperature of the nuclear power plant in a year, determine the highest temperature of the temperature gauge A6 on the cooling water outlet 5 pipeline of the equipment. This temperature is the highest cooling water temperature T2.

[0054] If the nuclear power plant is in operation, the lowest and highest readings of the annual temperature gauge 6 can be obtained directly by retrieving the parameter curves from the main control room, which are the highest and lowest temperatures of the cooling water.

[0055] Step 2: Confirm that the non-regenerative heat exchanger 13 heat exchange unit is operating normally;

[0056] Step 2.1: Confirm that the cooling water flow rates through the cooling water inlet B10 and cooling water outlet B12 of the non-regenerative heat exchanger 13 are normal;

[0057] Step 2.2: Confirm that the control valve 11 is operating normally;

[0058] Step 2.3: Confirm that the flow rate of the cooled medium flowing into inlet B7 of the non-regenerative heat exchanger 13 is normal;

[0059] Step 3: When the cooling water temperature of the cooling water heat exchanger 3 drops from the highest temperature to the lowest temperature, measure the temperature and flow rate changes of the cooling water in the non-regenerative heat exchanger 13.

[0060] Step 3.1: When the temperature and flow rate of the cooled medium at the inlet B7 of the non-regenerative heat exchanger 13 are at the design flow rate and temperature, control the cooling water temperature to decrease from the highest cooling water temperature to the lowest temperature, that is, the reading of temperature gauge A6 decreases from the highest cooling water temperature to the lowest temperature. Record the opening change of regulating valve 11, the temperature value changes of temperature gauge C14 and temperature gauge B9; record that when temperature gauge A6 is at the highest temperature T2, the reading of temperature gauge C14 is T3 and the reading of temperature gauge B9 is T5; record that when temperature gauge A6 is at the lowest temperature T1, the reading of temperature gauge C14 is T4 and the reading of temperature gauge B9 is T6.

[0061] Step 3.2: Compare the difference between T5 and T6. If the difference exceeds 5℃, it indicates that the temperature difference in the pipeline is too large. In this case, it is necessary to adjust the cooling water temperature setpoint and critical setpoint of temperature gauge B9 used to control valve 11. At the same time, it is necessary to set a cooling water temperature critical value for temperature gauge A6 to control gauge 9 to switch between the cooling water temperature setpoint and critical setpoint.

[0062] Step 3.3: When the temperature gauge A6 reaches the lowest temperature T1, gradually increase the opening of the regulating valve 11 to increase the cooling water flow through the cooling water inlet B, so as to reduce the reading of the temperature gauge C14 until the reading of the temperature gauge C14 is slightly lower than the maximum acceptable operating temperature of the pipeline 12, and record the reading of the temperature gauge B9 at this time as T7.

[0063] Step 3.4: Determine the maximum value T8 of the reading corresponding to temperature gauge A6 when temperature gauge C14 is at the highest acceptable operating temperature through data analysis;

[0064] Step 4: Set the temperature comparison value, critical setpoint, and temperature setpoint of the control unit;

[0065] Step 4.1: Set the maximum value T8+2℃ of the temperature reading of thermometer A6 obtained in step 3.4 as the temperature comparison value of comparator 15;

[0066] Step 4.2: Set the temperature setpoint as T7+5℃ obtained from the temperature gauge B9 in Step 3.3, and set the temperature setpoint as T7 obtained from the temperature gauge B9 in Step 3.3;

[0067] Step 5: Configure a logic for selector 16 so that when the output of comparator 15 changes, selector 16 gradually increases or decreases from one fixed value to another at a rate ΔK. That is, when the output of comparator 15 changes from 0 to 1, the fixed value of the output of selector 16 gradually decreases from T7+5℃ to T7 at a rate ΔK, where the value of ΔK does not exceed 1℃ / min.

[0068] With the above settings, when the reading of thermometer 6 input to comparator 15 is higher than the temperature comparison value T8+2℃, comparator 15 outputs 0 to downstream selector 16. Selector 16 outputs the setpoint value T7+5℃ to downstream comparator 17. Comparator 17 compares the temperature setpoint output by selector 16 with the measured value input by thermometer B9 and outputs an opening command to valve 11 to regulate the temperature of pipeline 12. When the reading of thermometer 6 input to comparator 15 is lower than the temperature comparison value T8+2℃, comparator 15 outputs 1 to downstream selector 16. Selector 16 outputs the critical setpoint value T7 to downstream comparator 17.

[0069] The above embodiments merely illustrate several implementation methods of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this patent should be determined by the appended claims.

Claims

1. A method for controlling the temperature regulating valve of a non-regenerative heat exchanger in a nuclear power plant, characterized in that, The method includes: Step 1: Determine the highest temperature T1 and the lowest temperature T2 of the cooling water in the cooling water heat exchanger (3); Step 2: Confirm that the non-regenerative heat exchanger (13) heat exchange unit is operating normally; Step 3: When the cooling water temperature of the cooling water heat exchanger (3) drops from the highest temperature to the lowest temperature, measure the temperature and flow rate changes of the cooling water in the non-regenerative heat exchanger (13). Step 3.1: When the temperature and flow rate of the cooled medium at the inlet B (7) of the non-regenerative heat exchanger (13) are at the design flow rate and temperature, control the cooling water temperature to drop from the highest cooling water temperature T1 to the lowest temperature T2, that is, the reading of temperature gauge A (6) drops from the highest cooling water temperature to the lowest temperature. Record the opening change of regulating valve (11), the temperature value change of temperature gauge C (14) and temperature gauge B (9); record that when temperature gauge A (6) is at the highest temperature T1, the reading of temperature gauge C (14) is T3 and the reading of temperature gauge B (9) is T5; record that when temperature gauge A (6) is at the lowest temperature T2, the reading of temperature gauge C (14) is T4 and the reading of temperature gauge B (9) is T6. Step 3.2: Compare the difference between T5 and T6. If the difference between T5 and T6 exceeds 5°C, the temperature comparison value, critical setting value, and temperature setting value of the control unit need to be set. Step 3.3: When the temperature gauge A (6) reaches the lowest temperature T1, gradually increase the opening of the regulating valve (11) until the reading of the temperature gauge C (14) is lower than the maximum acceptable operating temperature of the pipeline, and record the reading of the temperature gauge B (9) as T7. Step 3.4: Determine the maximum value T8 of the reading of temperature gauge A(6) when temperature gauge C(14) is at the highest acceptable operating temperature; Step 4: Set the temperature comparison value, critical setpoint, and temperature setpoint of the control unit.

2. The method for controlling the temperature regulating valve of a non-regenerative heat exchanger in a nuclear power plant according to claim 1, characterized in that, Step one includes: Step 1.1: Obtain seawater temperature variation data for the nuclear power plant over a year; Step 1.2: Introduce seawater at the same flow rate as designed into the inlet A(1) of the cooling water heat exchanger (3); Step 1.3: Introduce equipment cooling water with the same design flow rate into the cooling water inlet A (4) of the cooling water heat exchanger (3) to confirm that the equipment cooling water system is operating normally; Step 1.4: When the seawater temperature drops to the lowest seawater temperature in the year at the nuclear power plant, determine the lowest temperature T1 of the temperature gauge A(6) on the equipment cooling water outlet pipeline; Step 1.5: When the seawater temperature rises to the highest value of the seawater temperature in the nuclear power plant in a year, determine the highest temperature T2 of the temperature gauge A(6) on the equipment cooling water outlet 5 pipeline.

3. The method for controlling the temperature regulating valve of a non-regenerative heat exchanger in a nuclear power plant according to claim 1, characterized in that, The first step specifically includes obtaining the lowest and highest readings of the annual temperature gauge A(6) of the nuclear power plant by retrieving the parameter curves from the main control room during the commissioning phase of the nuclear power plant.

4. The method for controlling the temperature regulating valve of a non-regenerative heat exchanger in a nuclear power plant according to claim 1, characterized in that, Step two includes: Step 2.1: Confirm that the cooling water flow rate through the cooling water inlet B (10) and cooling water outlet B (12) of the non-regenerative heat exchanger (13) is normal; Step 2.2: Confirm that the control valve (11) is operating normally; Step 2.3: Confirm that the flow rate of the cooled medium flowing into inlet B (7) of the non-regenerative heat exchanger (13) is normal.

5. The method for controlling the temperature regulating valve of a non-regenerative heat exchanger in a nuclear power plant according to claim 1, characterized in that, In step 3.4, when the temperature value of temperature gauge C (14) reaches the highest acceptable operating temperature, the highest acceptable operating temperature is specifically the outlet cooling water temperature of the non-regenerative heat exchanger (13) where the downstream pipeline is not subject to thermal shock.

6. The method for controlling the temperature regulating valve of a non-regenerative heat exchanger in a nuclear power plant according to claim 1, characterized in that, Step four, setting the temperature comparison value, critical setpoint, and temperature setpoint of the control unit, specifically includes: Step 4.1: Set the maximum value T8+2℃ of the temperature reading of the temperature gauge A(6) obtained in step 3.4 as the temperature comparison value of the comparator (15); Step 4.2: Set the temperature setting value as T7+5℃ of the temperature gauge B(9) obtained in step 3.3, and set the temperature setting value as T7 of the temperature gauge B(9) obtained in step 3.

3.

7. The method for controlling the temperature regulating valve of a non-regenerative heat exchanger in a nuclear power plant according to claim 1, characterized in that, After step four, the selector (16) is set with a rate ΔK. When the output of the comparator (15) changes, the selector (16) changes its output value through the rate ΔK.

8. A temperature regulating valve control system for a non-regenerative heat exchanger in a nuclear power plant, wherein the system employs the temperature regulating valve control method for a non-regenerative heat exchanger in a nuclear power plant as described in any one of claims 1-7, characterized in that... The system includes a cooling water heat exchange unit, a non-regenerative heat exchanger (13) heat exchange unit, and a control unit. The cooling water heat exchange unit includes a cooling water heat exchanger (3) and a temperature gauge A (6). The cooling water heat exchanger (3) has a seawater channel and a cooling water channel. The cooling water outlet A (5) of the cooling water heat exchanger (3) is connected to the non-regenerative heat exchanger (13) heat exchange unit via a pipeline. The temperature gauge A (6) is installed on the pipeline connected to the cooling water outlet A (5) of the cooling water heat exchanger (3). The non-regenerative heat exchanger (13) heat exchange unit includes a non-regenerative heat exchanger (13), a temperature gauge B (9), a temperature gauge C (14), and a regulating valve (11). The device (13) is provided with a cooling medium channel and a cooling water channel. The cooling water inlet B (10) of the non-regenerative heat exchanger (13) is connected to the cooling water outlet A (5) of the cooling water heat exchanger (3). The pipeline connected to the cooling medium channel outlet A (2) of the non-regenerative heat exchanger (13) is provided with a thermometer B (9). The pipeline connected to the cooling water outlet B (12) of the non-regenerative heat exchanger (13) is provided with a regulating valve (11), a thermometer C (14) and an ultrasonic flow meter in sequence. The control unit is connected to the regulating valve (11), the thermometer A (6) and the thermometer B (9). The control unit controls the opening of the regulating valve (11) to maintain a constant temperature value of the thermometer B (9).

9. A temperature regulating valve control system for a non-regenerative heat exchanger in a nuclear power plant according to claim 8, characterized in that, The control unit includes a comparator (15), a selector (16), and a downstream comparator (17). The comparator (15) is connected to a temperature gauge A (6). The comparator (15) sets a temperature comparison value. The comparator (15) compares the temperature of the temperature gauge A (6) with the temperature comparison value. Based on the comparison result, the comparator (15) controls the output value of the selector (16). The selector (16) internally sets a critical setpoint and a temperature setpoint. The selector (16) selects to output the critical setpoint or the temperature setpoint to the downstream comparator (17) according to the instruction of the comparator (15). The downstream comparator (17) is connected to a temperature gauge B (9) and a regulating valve (11) respectively. The downstream comparator (17) compares the output value of the selector (16) with the measured value of the temperature gauge B (9). The downstream comparator (17) controls the flow rate of the regulating valve (11) to make the measured value of the temperature gauge B (9) consistent with the output value of the selector (16).

10. A temperature regulating valve control system for a non-regenerative heat exchanger in a nuclear power plant according to claim 9, characterized in that, When the measured value of thermometer A (6) is greater than or equal to the temperature comparison value, the comparator (15) of the control unit controls the selector (16) to output the temperature set value, and the controller controls the flow rate of the regulating valve (11) to make the measured value of thermometer B (9) the same as the temperature set value; when the measured value of thermometer A (6) is lower than the temperature comparison value, the comparator (15) of the control unit controls the selector (16) to output the critical set value, and the controller controls the flow rate of the regulating valve (11) to make the measured value of thermometer B (9) the same as the critical set value; when the selector (16) adjusts the output value to the temperature set value to the critical set value or adjusts the output value to the critical set value to the temperature set value, the adjustment rate of the selector (16) is the set value change rate ΔK, and the value of ΔK does not exceed 1℃ / min.

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