Operation control method of nuclear energy industry steam supply system

Abstract

The invention relates to the field of nuclear energy comprehensive utilization, in particular to an operation control method of a nuclear energy industry steam supply system. The method comprises the following steps: step 1, setting a total load value of a secondary circuit; the total load value of the secondary loop comprises a steam turbine generator load and a nuclear energy steam supply load; the reactor power is maintained at a full power level to reduce the total load fluctuation of the secondary loop to the greatest extent; 2, nuclear energy steam supply steam flow is obtained, the nuclear energy steam supply steam flow is multiplied by a coefficient K, and a nuclear energy steam supply load is obtained through calculation; the coefficient K is obtained according to the ratio of the unit main steam power generation degree to the electric power of the original steam turbine generator; 3, according to the total load value of the secondary circuit and the nuclear energy steam supply load, the load upper limit value of the steam turbine generator is calculated; and step 4, adjusting an electric power set value according to the upper limit value of the load of the steam turbine generator. According to the invention, safe operation of the main steam supply system of the nuclear reactor in an industrial steam supply mode is realized.

Description

Technical Field

[0001] The invention relates to the field of comprehensive utilization of nuclear energy, and in particular to an operation control method of a nuclear energy industrial steam supply system. Background Art

[0002] Industrial steam supply for nuclear power plants has obvious advantages in energy conservation and environmental protection. It is an effective way to replace fossil fuels and reduce carbon emissions. It meets the requirements of combined supply of electricity, heat, steam and other energy to achieve cascade utilization of energy and maximizes energy utilization efficiency.

[0003] For nuclear energy steam supply projects, industrial steam parameters are required to be relatively high, and the solution of using high-pressure cylinder exhaust steam to heat feed water to produce industrial steam is difficult to meet the requirements. Therefore, using the main steam of the nuclear power plant as the heat source of the steam production device to produce qualified industrial steam is relatively easy to achieve, with higher safety and higher technical feasibility.

[0004] Existing pressurized water reactor nuclear power units basically operate in the reactor power follows turbine power mode. The reactor provides high-temperature and high-pressure steam to the turbine generator unit through the steam generator. When nuclear energy is used to supply steam, the heating steam is extracted from the main steam pipeline and transported to the steam production device to heat the desalted water on the opposite side to produce industrial steam supply. At this time, the turbine generator power cannot represent the actual load on the secondary side. It is necessary to add the nuclear energy steam supply load through effective means and adjust the original operation mode to meet the needs of the reactor, turbine and steam supply, and ensure the safety of the nuclear reactor. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide an operation control method for a nuclear energy industrial steam supply system to achieve safe operation of a nuclear reactor main steam supply system under an industrial steam supply mode.

[0006] The present invention provides an operation control method for a nuclear energy industrial steam supply system, comprising the following steps:

[0007] Step 1: setting the total load value of the secondary circuit; the total load value of the secondary circuit includes the steam turbine generator load and the nuclear energy steam supply load; maintaining the reactor power at the full power level to minimize the fluctuation of the total load of the secondary circuit;

[0008] Step 2: Obtain the steam flow rate of nuclear energy steam supply, multiply the steam flow rate of nuclear energy steam supply by coefficient K, and calculate the nuclear energy steam supply load; the coefficient K is obtained according to the ratio of the unit main steam power generation degree to the original steam turbine generator power;

[0009] Step 3: Calculate the upper limit of the steam turbine generator load based on the total load value of the secondary circuit and the nuclear energy steam supply load;

[0010] Step 4: adjusting the electric power setting value according to the upper limit value of the steam turbine generator load;

[0011] When the steam flow rate of nuclear energy steam supply changes, the upper limit value of the steam turbine generator load changes with the nuclear energy steam supply load. If the upper limit value of the steam turbine generator load is higher than the electric power setting value, the electric power remains stable.

[0012] If the upper limit of the turbine generator load is lower than the electric power setting value, the electric power will be reduced to prevent the total load value of the secondary circuit from exceeding the limit.

[0013] In a specific embodiment of the present invention, in step 1, the total load value of the secondary loop is not higher than the upper limit of the reactor power.

[0014] In a specific embodiment of the present invention, in step 1, the total load value of the secondary circuit is manually input by an operator in the main control room.

[0015] In a specific embodiment of the present invention, in step 3, the upper limit value of the steam turbine generator load is the difference between the total load value of the secondary circuit and the nuclear energy steam supply load.

[0016] In a specific embodiment of the present invention, the step 3 further includes:

[0017] The upper limit of the turbine generator load is set to be higher than the difference between the total load of the secondary circuit and the nuclear energy steam supply load.

[0018] In a specific embodiment of the present invention, in step 4, the upper limit of the turbine generator load is set to be higher than the difference between the secondary circuit total load value and the nuclear energy steam supply load, and the range above the difference is 5% to 10% of the rated load.

[0019] In a specific embodiment of the present invention, the step 4 further includes:

[0020] When there is an operational need or the unit is abnormal or the power grid requires reducing the load of the steam turbine generator, manually enter the upper limit value of the steam turbine generator to manually reduce the electric power of the steam turbine generator.

[0021] In a specific embodiment of the present invention, in step 3, when the steam flow rate of nuclear energy steam supply increases, since the total load setting value of the secondary circuit remains unchanged, the upper limit value of the steam turbine generator load decreases; when the steam flow rate of nuclear energy steam supply decreases, the upper limit value of the steam turbine generator load increases.

[0022] In a specific embodiment of the present invention, in step 5,

[0023] When the steam flow rate of nuclear energy steam supply increases, since the total load value of the secondary circuit remains unchanged, the upper limit of the steam turbine generator load decreases. If the upper limit of the steam turbine generator load is higher than the electric power setting value, the electric power remains stable.

[0024] If the upper limit of the turbine generator load is lower than the set value of the electric power, the electric power is reduced to prevent the total load value of the secondary circuit from exceeding the limit;

[0025] When the steam flow rate of nuclear energy steam supply decreases, since the total load value of the secondary circuit remains unchanged, the upper limit of the steam turbine generator load increases. If the upper limit of the steam turbine generator load is higher than the electric power setting value, the electric power remains stable or the electric power setting value increases.

[0026] Compared with the prior art, the operation control method of the nuclear energy industrial steam supply system of the present invention can adjust the turbine load in real time according to the steam extraction volume, avoid the total load of the secondary circuit exceeding the limit, and ensure the safety of the reactor system; the unit can specify the electrical load, which has little impact on the original operation mode of the unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 A schematic diagram showing the flow of the nuclear power industry steam supply system;

[0028] Figure 2 Schematic diagram of the operation control system for steam supply to the nuclear energy industry. DETAILED DESCRIPTION

[0029] In order to further understand the present invention, the embodiments of the present invention are described below in conjunction with examples, but it should be understood that these descriptions are only for further illustrating the features and advantages of the present invention, rather than limiting the present invention.

[0030] The solution for nuclear power industry steam supply is as follows: Figure 1 As shown in the figure, the steam generator is a production device for the secondary circuit main steam of a nuclear power plant. Its heating heat source is the primary circuit coolant of the nuclear power plant. It heats the secondary circuit feed water to make it high-pressure saturated steam, and then transports it to the steam turbine generator set through the main steam pipeline for power generation. In the nuclear energy industrial steam supply mode, a new extraction pipeline is added to the main steam pipeline to introduce the main steam into the heat exchange station of the nuclear energy industrial steam supply. It passes through the superheater, evaporator, and preheater in sequence to heat the water on the industrial steam side to generate steam that meets the steam requirements. On the tertiary side (steam supply side), seawater is desalinated and desalinated, and then preheated by the condensed water on the secondary side (secondary circuit extraction side), then evaporated into saturated steam by the evaporator, and finally heated into superheated steam by the superheater. The superheated steam is transported to the user through the external transmission pipeline network.

[0031] Compared with the normal operation mode of nuclear power plants, in the nuclear energy steam supply operation mode, the steam generated by the steam generator provides steam to the steam turbine and the industrial steam supply heat exchange station at the same time. Accordingly, the heat load of the secondary circuit is changed from the previous representation of the heat load of the steam turbine generator to the sum of the heat load of the steam turbine generator and the nuclear energy steam supply load.

[0032] The embodiment of the present invention discloses an operation control method of a nuclear energy industrial steam supply system, such as Figure 2 As shown, the following steps are included:

[0033] Step 1: setting the total load value of the secondary circuit; the total load value of the secondary circuit includes the steam turbine generator load and the nuclear energy steam supply load; maintaining the reactor power at the full power level to minimize the fluctuation of the total load of the secondary circuit;

[0034] The total load value of the secondary circuit is not higher than the upper limit of the reactor power; the total load value of the secondary circuit is manually input by the operator in the main control room;

[0035] The load value and load can be expressed in correspondence with the corresponding power;

[0036] Step 2: Obtain the steam flow rate of nuclear energy steam supply, multiply the steam flow rate of nuclear energy steam supply by coefficient K, and calculate the nuclear energy steam supply load; the coefficient K is obtained according to the ratio of the unit main steam power generation degree to the original steam turbine generator power;

[0037] In the nuclear energy steam supply mode, part of the main steam enters the steam turbine generator for power generation, and the other part is used for nuclear energy steam supply. This part of the main steam used for nuclear energy steam heating reduces the electric power of the steam turbine generator. The reduced electric power of the steam turbine generator is the nuclear energy steam supply load.

[0038] There is a corresponding relationship between the nuclear energy steam supply load and the nuclear energy steam supply steam flow rate.

[0039] The ratio between the nuclear energy steam supply load and the nuclear energy steam supply steam flow is a coefficient K, which is obtained through design analysis and corrected according to field measured data;

[0040] By obtaining the steam flow rate of nuclear energy steam supply and multiplying it by the coefficient K, the corresponding electric power value can be obtained. This value is the electric power value corresponding to the nuclear energy steam supply load, that is, the electric power value lost by the steam turbine generator due to the extraction of nuclear energy steam supply. The coefficient K is obtained based on the ratio of the unit main steam power generation to the original steam turbine generator power, where the unit main steam power generation range is 260~270KWh / t steam.

[0041] Different extraction steam flow rates correspond to different coefficients K, and these coefficients can be fitted to obtain a proportional curve.

[0042] Therefore, the nuclear steam supply load is equal to the product of the nuclear steam supply steam flow rate and the coefficient K.

[0043] Step 3: Calculate the upper limit of the steam turbine generator load based on the total load value of the secondary circuit and the nuclear energy steam supply load;

[0044] Theoretically, the upper limit of the steam turbine generator load is the difference between the total load value of the secondary circuit and the nuclear energy steam supply load.

[0045] During actual operation, when there is a need for operation or unit abnormality or the grid requires the turbine generator load to be reduced, the turbine generator load upper limit is set to a value higher than the difference between the secondary circuit total load value and the nuclear energy steam supply load;

[0046] The upper limit of the turbine generator load is set to be higher than the difference between the total load of the secondary circuit and the nuclear steam supply load, usually in the range of 5% to 10% of the rated load.

[0047] When the steam supply demand increases, that is, the steam flow rate of nuclear steam supply increases, the upper limit of the steam turbine generator load decreases because the total load setting value of the secondary circuit remains unchanged; when the external steam supply demand decreases, that is, the steam flow rate of nuclear steam supply decreases, the upper limit of the steam turbine generator load increases.

[0048] Step 4: adjusting the electric power setting value according to the upper limit value of the steam turbine generator load;

[0049] The electric power setting value is manually set and obtained from the power grid frequency modulation signal, and does not exceed the upper limit of the steam turbine generator load;

[0050] When there is a need for operation or the unit is abnormal or the power grid requires to reduce the load of the steam turbine generator, manually input the upper limit of the steam turbine generator load to manually reduce the electric power of the steam turbine generator;

[0051] When the steam flow rate of nuclear energy steam supply changes, the upper limit value of the steam turbine generator load changes with the nuclear energy steam supply load. If the upper limit value of the steam turbine generator load is higher than the electric power setting value, the electric power remains stable.

[0052] If the upper limit of the turbine generator load is lower than the electric power setting value, the electric power will be reduced to prevent the total load value of the secondary circuit from exceeding the limit.

[0053] Specifically, in step 5, when the steam flow rate of nuclear energy steam supply increases, since the total load value of the secondary circuit remains unchanged, the upper limit value of the steam turbine generator load decreases. If the upper limit value of the steam turbine generator load is higher than the electric power setting value, the electric power remains stable.

[0054] If the upper limit of the turbine generator load is lower than the set value of the electric power, the electric power is reduced to prevent the total load value of the secondary circuit from exceeding the limit;

[0055] When the steam flow rate of nuclear energy steam supply decreases, since the total load value of the secondary circuit remains unchanged, the upper limit of the steam turbine generator load increases. If the upper limit of the steam turbine generator load is higher than the electric power setting value, the electric power remains stable or the electric power setting value increases.

[0056] The above embodiments are only used to help understand the method and core idea of ​​the present invention. It should be noted that, for those skilled in the art, several improvements and modifications can be made to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

[0057] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An operation control method for a nuclear energy industrial steam supply system, characterized in that: The following steps are involved: Step 1: setting the total load value of the secondary circuit; the total load value of the secondary circuit includes the steam turbine generator load and the nuclear energy steam supply load; maintaining the reactor power at the full power level to minimize the fluctuation of the total load of the secondary circuit; Step 2: Obtain the steam flow rate of nuclear energy steam supply, multiply the steam flow rate of nuclear energy steam supply by coefficient K, and calculate the nuclear energy steam supply load; the coefficient K is obtained according to the ratio of the unit main steam power generation degree to the original steam turbine generator power; Step 3: Calculate the upper limit of the steam turbine generator load based on the total load value of the secondary circuit and the nuclear energy steam supply load; Step 4: adjusting the electric power setting value according to the upper limit value of the steam turbine generator load; When the steam flow rate of nuclear energy steam supply changes, the upper limit value of the steam turbine generator load changes with the nuclear energy steam supply load. If the upper limit value of the steam turbine generator load is higher than the electric power setting value, the electric power remains stable. If the upper limit of the turbine generator load is lower than the electric power setting value, the electric power will be reduced to prevent the total load value of the secondary circuit from exceeding the limit.

2. The operation control method of the nuclear energy industry steam supply system according to claim 1, characterized in that: In step 1, the total load value of the secondary circuit is not higher than the upper limit value of the reactor power.

3. The operation control method of the nuclear energy industry steam supply system according to claim 1, characterized in that: In step 1, the total load value of the secondary circuit is manually input by the operator in the main control room.

4. The operation control method of the nuclear energy industry steam supply system according to claim 1, characterized in that: In step 3, the upper limit of the turbine generator load is the difference between the total load value of the secondary circuit and the nuclear energy steam supply load.

5. The operation control method of the nuclear energy industry steam supply system according to claim 1, characterized in that: The step 3 further includes: The upper limit of the turbine generator load is set to be higher than the difference between the total load of the secondary circuit and the nuclear energy steam supply load.

6. The operation control method of the nuclear energy industry steam supply system according to claim 5, characterized in that: In step 4, the upper limit of the turbine generator load is set to be higher than the difference between the secondary circuit total load value and the nuclear energy steam supply load, and the range of higher than the difference is 5% to 10% of the rated load.

7. The operation control method of the nuclear energy industry steam supply system according to claim 1, characterized in that: The step 4 further includes: When there is an operational need or the unit is abnormal or the power grid requires reducing the load of the steam turbine generator, manually enter the upper limit value of the steam turbine generator to manually reduce the electric power of the steam turbine generator.

8. The operation control method of the nuclear energy industry steam supply system according to claim 1, characterized in that: In step 3, when the steam flow rate of nuclear energy steam supply increases, since the total load setting value of the secondary circuit remains unchanged, the upper limit value of the steam turbine generator load decreases; when the steam flow rate of nuclear energy steam supply decreases, the upper limit value of the steam turbine generator load increases.

9. The operation control method of the nuclear energy industry steam supply system according to claim 1, characterized in that: In step 5, When the steam flow rate of nuclear energy steam supply increases, since the total load value of the secondary circuit remains unchanged, the upper limit of the steam turbine generator load decreases. If the upper limit of the steam turbine generator load is higher than the electric power setting value, the electric power remains stable. If the upper limit of the turbine generator load is lower than the set value of the electric power, the electric power is reduced to prevent the total load value of the secondary circuit from exceeding the limit; When the steam flow rate of nuclear energy steam supply decreases, since the total load value of the secondary circuit remains unchanged, the upper limit of the steam turbine generator load increases. If the upper limit of the steam turbine generator load is higher than the electric power setting value, the electric power remains stable or the electric power setting value increases.

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