Optimization method for improving thermoelectric power matching degree of nuclear power unit

Abstract

The invention relates to the technical field of nuclear power plant power generation optimization, and discloses an optimization method for improving the thermoelectric power matching degree of a nuclear power unit, which comprises the following steps: acquiring real-time data of characteristic parameters related to unit output, storing the real-time data in a characteristic parameter database, and establishing an estimation database according to change characteristics of the characteristic parameter database during daily power increasing and decreasing; and comparing the estimation database with the real-time characteristic parameters of the unit, outputting a judgment value, judging whether the margin for further improving the power exists, and comparing the deviation between the estimation database and the real-time data in real time when the electric power is improved. According to the method, characteristic parameters related to unit output are collected in real time, the characteristic parameters are compared with an estimation database generated through calculation of the Lagrange interpolation method, a judgment value is output, whether the allowance for further improving the electric power exists or not is given, and therefore thermoelectric power matching is further optimized.

Description

Technical Field

[0001] The present invention relates to the technical field of nuclear power plant power generation optimization, and in particular to an optimization method for improving the thermal power matching degree of a nuclear power unit. Background Art

[0002] In winter, existing nuclear power units experience lower seawater temperature, higher condenser vacuum, and improved steam-water cycle efficiency, which results in reactor output loss when the electric power is at full capacity but the nuclear power is not at full capacity. Summary of the invention

[0003] The purpose of the present invention is to provide an optimization method for improving the thermal power matching degree of a nuclear power unit, thereby solving the problem that the nuclear power unit cannot accurately and fully generate electric power under winter conditions.

[0004] In order to achieve the above object, the present invention provides the following technical solutions:

[0005] An optimization method for improving the thermal power matching degree of a nuclear power unit, collecting real-time data of characteristic parameters related to the unit output and storing them in a characteristic parameter database; establishing an estimation database according to the change characteristics of the characteristic parameter database during daily power increase and decrease; comparing the estimation database with the real-time characteristic parameters of the unit, outputting a judgment value, and judging whether there is a margin for further power increase; when increasing the electric power, comparing the deviation between the estimation database and the real-time data in real time, and promptly reminding the operator to strengthen monitoring and adjustment when the deviation is large.

[0006] In some embodiments, during the process of increasing electric power, the deviation between the characteristic parameters and the estimated values ​​in the estimation database is monitored in real time. If the deviation between the actual data and the estimated values ​​is greater than 10%, the operator is promptly reminded to strengthen control and make adjustments.

[0007] In some embodiments, the database is established by collecting the thermal power distribution of the unit in the past three years, and the sample points of the estimation database are taken from different power platforms of the unit during peak load regulation under winter conditions in the past year.

[0008] In some embodiments, characteristic parameters related to the unit output include channel nuclear power, thermal power, power distribution unevenness coefficient, fuel element linear power density, average temperature of hot / cold sections of each loop, reactor core pressure, instantaneous value of axial deviation of power distribution, deviation of fuel element surface from nucleate boiling ratio, seawater temperature, operation of deaerator water supply regulating valve and steam generator feed water regulating valve, turbine bearing and bushing vibration, condenser vacuum, and water chemical conditions.

[0009] In some embodiments, the optimization method for improving the thermal power matching degree of a nuclear power unit specifically comprises the following steps:

[0010] S1: Collect real-time data of characteristic parameters related to unit output and save them in the characteristic parameter database;

[0011] S2: performing Lagrangian interpolation calculation on characteristic parameters in the winter working condition by sampling the nuclear power in the range of 80%N to 100%N according to the characteristic parameter database, and establishing an estimation database;

[0012] S3: Compare the characteristic parameters in the estimation database with the corresponding limit values ​​to determine whether there is room for further power increase. If so, increase the electric power by 0.18% according to the plan; if not, maintain the current power and compare again every 24 hours until the judgment is yes.

[0013] S4: While increasing the electric power according to the plan, monitor the deviation between the actual data and the characteristic parameters in the estimated database in real time. If the deviation is greater than 10%, remind the operator to correct the deviation in time;

[0014] S5: After the electric power is increased by 0.18%, sampling is performed again according to the increased power to perform Lagrange interpolation recalculation, update the estimation database, and re-determine the margin for further electric power increase.

[0015] In some embodiments, the electric power calculated in S2 is Lagrangian interpolation of characteristic parameters when the full power increases by 0.18% every time.

[0016] In some embodiments, the estimation database of the characteristic parameter increasing by 0.18% electric power is compared with the limit value of the corresponding parameter to determine whether there is a margin for increasing power, specifically including:

[0017] The channel nuclear power is judged to be less than 100.5% FP, the surface deviation of the fuel element from the nucleate boiling ratio is ≥1.30, the linear power density of the fuel element is judged to be ≤101.5% FP constant, the instantaneous value of the axial deviation of the power distribution is judged to be maintained near the equilibrium AO*, the core pressure is judged to be controllable within the range of 15.3MPa-15.9MPa, the deaerator water supply regulating valve and the steam generator feed water regulating valve are judged to operate normally and without abnormal fluctuations, the maximum value of the turbine bearing vibration is judged to be less than 0.17mm, the maximum value of the turbine bearing vibration is judged to be less than 0.085mm, and the positive conductivity of the secondary circuit feed water and the steam generator wastewater is judged to be ≤0.15μs / cm.

[0018] In some embodiments, when there is a margin for increasing electric power, the electric power is increased by 0.18%. After the power is increased and stabilized, the current power is sampled again, and Lagrange interpolation is performed to increase the electric power by 0.18% again and the estimation database is updated. The margin judgment is re-performed, and the electric power is increased in a step-by-step manner and the margin judgment is performed.

[0019] In some embodiments, during the power boosting process, the changes in various characteristic parameters are monitored in real time. If the deviation from the estimation database is greater than 10%, an alarm is triggered and it is determined whether the power boosting needs to be stopped.

[0020] In some embodiments, three measuring points are provided in the hot section and the cold section of each loop of the nuclear power unit, and the arithmetic mean of 3 times 2 is taken to obtain the average temperature of the section of each loop.

[0021] Compared with the prior art, the optimization method for improving the thermoelectric power matching degree of a nuclear power unit provided by the present invention has the following beneficial effects:

[0022] The present invention collects characteristic parameters related to the unit output in real time, compares them with the estimation database calculated and generated by the Lagrange interpolation method, outputs a judgment value, and gives whether there is a margin for further increasing the electric power, thereby further optimizing the thermal power matching.

[0023] When increasing electric power, the deviation between the estimated database and the real-time data is compared in real time. When the deviation is large, the operator is promptly reminded to strengthen monitoring and adjustment, thereby improving the actual power generation capacity of the unit while ensuring safe and stable operation of the unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solution of the present invention, the following briefly introduces the drawings required for the technical description.

[0025] Figure 1 A flow chart of an optimization method for improving the thermal power matching degree of a nuclear power unit provided by the present invention. DETAILED DESCRIPTION

[0026] The following is further explained in detail through specific implementation methods.

[0027] like Figure 1 As shown, the present invention provides an optimization method for improving the thermal power matching degree of a nuclear power unit, collects and establishes a characteristic parameter database related to the unit output; according to the change characteristics of the characteristic parameter database during daily power increase and decrease, the Lagrange interpolation method is used to estimate the characteristic parameter changes brought about by further power increase and establish an estimation database; when the unit is in winter conditions, the secondary circuit efficiency is improved, when the secondary circuit electric power is fully generated and the primary circuit nuclear power does not reach the rated condition, the estimation database is compared with the limit value of the corresponding characteristic parameter to determine whether there is a margin for increasing the power, and if so, the electric power is further increased; in the process of increasing the electric power, the deviation between the characteristic parameter and the estimated value in the estimation database is monitored in real time, and if the deviation between the actual data and the estimated value is greater than 10%, the operator is promptly reminded to strengthen control and make adjustments.

[0028] According to existing practical experience, the power of a single unit can be increased by 10MW under winter conditions, bringing greater economic benefits.

[0029] Specifically, Figure 1 As shown, the optimization method provided by the present invention comprises the following steps:

[0030] S1. Collect real-time data of characteristic parameters related to unit output and save them in a characteristic parameter database;

[0031] S2. Perform Lagrange interpolation calculation on characteristic parameters in the winter working condition by sampling the nuclear power in the range of 80%N to 100%N according to the characteristic parameter database, and establish an estimation database;

[0032] S3. Compare the characteristic parameters in the estimation database with the corresponding limit values ​​to determine whether there is room for further power increase; if so, increase the electric power by 0.18% according to the plan; if not, maintain the current power and compare again every 24 hours until the judgment is yes.

[0033] S4. While increasing the electric power according to the plan, monitor the deviation between the actual data and the characteristic parameters in the estimated database in real time. If the deviation is greater than 10%, remind the operator to correct the deviation in time;

[0034] S5. After the electric power is increased by 0.18%, the Lagrange interpolation calculation is performed again according to the increased power, the estimation database is updated, and the margin for further electric power increase is re-determined.

[0035] In one embodiment, the database is established by collecting the thermal / electric power distribution of the unit in the past three years, and the sample points of the estimation database are taken from different power platforms of the unit during peak load regulation under winter conditions in the past year.

[0036] In one embodiment, when the margin judgment is feasible, the estimation database update after the power is increased can eliminate the error in the next margin judgment and improve the accuracy of the data.

[0037] In one embodiment, characteristic parameters related to the unit output include channel nuclear power, thermal power, power distribution unevenness coefficient, fuel element linear power density, average temperature of hot section / cold section of each loop, reactor core pressure, instantaneous value of axial deviation of power distribution, deviation of fuel element surface from nucleate boiling ratio, seawater temperature, operation of deaerator / steam generator feed water regulating valve, turbine bearing / bearing vibration, condenser vacuum and water chemical conditions.

[0038] In one embodiment, the nuclear power unit includes four loops, and the hot section / cold section of each loop has three measuring points, and the arithmetic mean of 3 times 2 is the average temperature of the section of each loop.

[0039] In one embodiment, the Lagrangian interpolation of the characteristic parameters is sampled in the range of 80%N to 100%N of nuclear power under winter conditions within a year, and the calculation includes: the Lagrangian interpolation of the characteristic parameters when the electric power increases by 0.18% every time from the full power 100%.

[0040] In one embodiment, the estimation database of the characteristic parameter increasing by 0.18% electric power is compared with the limit value of the corresponding parameter to determine whether there is a margin for increasing power, specifically including:

[0041] The channel nuclear power is judged to be less than 100.5% FP, the surface deviation of the fuel element from the nucleate boiling ratio is ≥1.30, the linear power density of the fuel element should not exceed the fixed value of 101.5% FP, the instantaneous value of the axial deviation of the power distribution is judged to be maintained in the recommended area of ​​the balanced AO*core, the core pressure is judged to be controllable within the range of 15.3MPa-15.9MPa, the deaerator / steam generator feed water regulating valve is judged to operate normally and without abnormal fluctuations, the maximum value of the turbine bearing vibration is judged to be less than 0.17mm, the maximum value of the turbine bearing vibration is judged to be less than 0.085mm, and the positive conductivity of the secondary circuit feed water and steam generator waste water is judged to be ≤0.15μs / cm.

[0042] In one embodiment, in the case of having a margin for increasing electric power, the electric power is increased by 0.18%. After the power is increased and stabilized, the current power is sampled again, and Lagrange interpolation is performed to increase the electric power by 0.18% again and the estimation database is updated, and the margin judgment is re-performed, and the electric power is increased in a step-by-step manner and the margin judgment is performed.

[0043] In one embodiment, during the power boosting process, the changes in various characteristic parameters are monitored in real time. If there is a deviation from the estimated database greater than 10%, an alarm is issued and it is determined whether the power boosting needs to be stopped.

[0044] In summary, the present invention compares the estimation database calculated by the Lagrange interpolation method according to the characteristic parameters with the parameter limits to determine whether there is room for further power increase. If so, the power can be increased. During the increase, the deviation between the characteristic parameters and the estimation database is monitored and corrected in real time, thereby achieving the improvement and optimization of the thermal power matching degree of the nuclear power unit, improving the unit output, and maximizing the power generation capacity of the power plant under the premise of ensuring the safe operation of the unit.

[0045] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by any technician familiar with the technical field within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. An optimization method for improving the thermal power matching degree of a nuclear power unit, characterized in that: Collect real-time data of characteristic parameters related to unit output and save them in the characteristic parameter database. Establish an estimation database based on the changing characteristics of the characteristic parameter database during daily power increase and decrease. Compare the estimation database with the real-time characteristic parameters of the unit and output a judgment value to determine whether there is room for further power increase. When increasing electric power, compare the deviation between the estimation database and the real-time data in real time.

2. The optimization method for improving the thermal power matching degree of a nuclear power unit according to claim 1, characterized in that: During the process of increasing electric power, the deviation between the characteristic parameters and the estimated values ​​in the estimation database is monitored in real time. If the deviation between the actual data and the estimated value is greater than 10%, the operator is promptly reminded to strengthen control and make adjustments.

3. The optimization method for improving the thermal power matching degree of a nuclear power unit according to claim 1, characterized in that: The database is established by collecting the thermal power and electric power distribution of the units in the past three years. The sample points of the estimated database are taken from different power platforms of the units during peak load regulation under winter operating conditions in the past year.

4. The optimization method for improving the thermal power matching degree of a nuclear power unit according to claim 1, characterized in that: The characteristic parameters related to the unit output include channel nuclear power, thermal power, power distribution unevenness coefficient, fuel element linear power density, average temperature of hot / cold sections of each loop, reactor core pressure, instantaneous value of axial deviation of power distribution, deviation of fuel element surface from nucleate boiling ratio, seawater temperature, operation of deaerator water supply regulating valve and steam generator feed water regulating valve, turbine bearing and bushing vibration, condenser vacuum, and water chemical conditions.

5. The optimization method for improving the thermal power matching degree of a nuclear power unit according to claim 1, characterized in that: The specific steps include: S1: Collect real-time data of characteristic parameters related to unit output and save them in the characteristic parameter database; S2: performing Lagrangian interpolation calculation on characteristic parameters in the winter working condition by sampling the nuclear power in the range of 80%N to 100%N according to the characteristic parameter database, and establishing an estimation database; S3: Compare the characteristic parameters in the estimation database with the corresponding limit values ​​to determine whether there is room for further power increase. If so, increase the electric power by 0.18% according to the plan; if not, maintain the current power and compare again every 24 hours until the judgment is yes. S4: While increasing the electric power according to the plan, monitor the deviation between the actual data and the characteristic parameters in the estimated database in real time. If the deviation is greater than 10%, remind the operator to correct the deviation in time; S5: After the electric power is increased by 0.18%, sampling is performed again according to the increased power to perform Lagrange interpolation recalculation, update the estimation database, and re-determine the margin for further electric power increase.

6. The optimization method for improving the thermal power matching degree of a nuclear power unit according to claim 5, characterized in that: The electric power calculated in S2 is the Lagrangian interpolation of the characteristic parameters every time the full power is increased by 0.18%.

7. The optimization method for improving the thermal power matching degree of a nuclear power unit according to claim 5, characterized in that: Compare the estimated database of the characteristic parameter increase of 0.18% electric power with the limit value of the corresponding parameter to determine whether there is margin for increasing power, including: The channel nuclear power is judged to be less than 100.5% FP, the surface deviation of the fuel element from the nucleate boiling ratio is ≥1.30, the linear power density of the fuel element is judged to be ≤101.5% FP constant, the instantaneous value of the axial deviation of the power distribution is judged to be maintained near the equilibrium AO*, the core pressure is judged to be controllable within the range of 15.3MPa-15.9MPa, the deaerator water supply regulating valve and the steam generator feed water regulating valve are judged to operate normally and without abnormal fluctuations, the maximum value of the turbine bearing vibration is judged to be less than 0.17mm, the maximum value of the turbine bearing vibration is judged to be less than 0.085mm, and the positive conductivity of the secondary circuit feed water and the steam generator wastewater is judged to be ≤0.15μs / cm.

8. The optimization method for improving the thermal power matching degree of a nuclear power unit according to claim 5, characterized in that: In the case of having a margin for increasing electric power, the electric power is increased by 0.18%. After the power is increased and stabilized, the current power is sampled again, and Lagrange interpolation is performed to increase the electric power by 0.18% again and the estimation database is updated. The margin judgment is re-performed, and the electric power is increased in a step-by-step manner and the margin judgment is performed.

9. The optimization method for improving the thermal power matching degree of a nuclear power unit according to claim 5, characterized in that: During the power boosting process, the changes of various characteristic parameters are monitored in real time. If the deviation from the estimated database is greater than 10%, an alarm is triggered and it is determined whether the power boosting needs to be stopped.

10. The optimization method for improving the thermal power matching degree of a nuclear power unit according to claim 5, characterized in that: There are three measuring points in the hot section and cold section of each loop of the nuclear power unit, and the arithmetic mean of 3 times 2 is taken to obtain the average temperature of this section of each loop.

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