Online detection system and method for OPC electromagnetic valve group of steam turbine generator unit

Abstract

The invention provides a steam turbine generator unit OPC solenoid valve group on-line detection system, the steam turbine generator unit OPC solenoid valve group on-line detection system comprises an OPC solenoid valve group, the OPC solenoid valve group comprises an oil inlet branch communicated with an oil inlet pipeline, the head end of the oil inlet pipeline is communicated with a GV hydraulic servo-motor on a steam turbine generator, and the head end of the oil inlet pipeline is communicated with an oil outlet pipeline. A check valve and an OPC electromagnetic valve are sequentially arranged on the oil inlet branch, the oil inlet branch is divided into a branch A and a branch B behind the OPC electromagnetic valve, the branch A and the branch B are respectively communicated with an oil outlet pipeline of the steam turbine generator oil return pipeline, a needle valve I is arranged on the branch A, and a needle valve II is arranged on the branch B; a needle valve II, a pressure gauge and a throttling orifice plate are sequentially arranged on the branch B, and the working state of the OPC electromagnetic valve is judged by controlling opening and closing of the needle valve I and the needle valve II and combining the reading change condition of the pressure gauge. The detection system provided by the invention is accurate in detection result and high in implementation of equipment transformation content.

Description

Technical Field

[0001] This invention relates to an online testing system for OPC solenoid valve groups, and more particularly to an online testing system and testing method for OPC solenoid valve groups in steam turbine generator sets. Background Technology

[0002] Existing steam turbine generator set protection systems generally rely on the action of OPC solenoid valves. When the steam turbine overspeeds and reaches 103% of its rated speed, the OPC solenoid valve activates, reduces the OPC oil pressure, temporarily closes the steam turbine's regulating valve, reduces the steam intake of the steam turbine, and lowers the steam turbine speed to the rated speed. Once the speed drops to the rated speed, the OPC solenoid valve is de-energized, the steam turbine regulating valve opens, the steam intake is restored, and the steam turbine resumes normal operation.

[0003] If the OPC protection solenoid valve malfunctions during the operation of the steam turbine generator set, the following hazards may occur:

[0004] (1) When the OPC protection solenoid valve receives an action signal, if the solenoid valve fails to operate, the protection will fail, causing a serious accident of overspeed of the unit, resulting in incalculable huge economic losses and social impact.

[0005] (2) When the OPC protection solenoid valve is activated, as long as the solenoid valve is not reset, the turbine generator speed control system will be unable to re-establish the pressure of the oil, causing the unit to be forced to shut down.

[0006] (3) When the OPC solenoid valve malfunctions during unit operation, it will cause the turbine generator unit to shut down unexpectedly, posing a great threat to downstream heat users and causing secondary accidents.

[0007] As can be seen from the above, the reliability of the OPC solenoid valve assembly will directly affect the reliability of the unit's protection.

[0008] The current protection system of steam turbine generator sets cannot detect the OPC solenoid valve group online. Therefore, it is impossible to determine whether the OPC solenoid valve group is faulty. This may cause the unit to operate in a state where the OPC solenoid valve group is faulty, which poses a significant safety hazard and affects the safety and reliability of the unit. Summary of the Invention

[0009] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide an online detection system and method for OPC solenoid valve groups in steam turbine generator sets, which solves the problem that the prior art cannot detect whether there is a fault in the OPC solenoid valve group online.

[0010] To achieve the above and other related objectives, the present invention is obtained through the following technical solution.

[0011] The first aspect of this invention is to provide an online detection system for OPC solenoid valve groups in a steam turbine generator set. The system includes an OPC solenoid valve group, which includes an oil inlet branch connected to the oil inlet pipeline. The first end of the oil inlet pipeline is connected to the GV hydraulic actuator on the steam turbine generator. A check valve and an OPC solenoid valve are sequentially arranged on the oil inlet branch. After the OPC solenoid valve, the oil inlet branch splits into branch A and branch B. Branch A and branch B are respectively connected to the oil outlet pipeline of the steam turbine generator's return oil pipeline. A needle valve is installed on branch A, and a needle valve, a pressure gauge, and an orifice plate are sequentially arranged on branch B. The operating status of the OPC solenoid valve is determined by controlling the opening and closing of needle valves one and two and combining this with changes in the pressure gauge reading.

[0012] In some embodiments of the present invention, there are at least two OPC solenoid valve assemblies, each connected in parallel between the oil inlet line and the oil outlet line. The OPC solenoid valve assemblies of the present invention can be configured as two, three, or more.

[0013] In some embodiments of the present invention, the branches B of multiple OPC solenoid valve assemblies are paralleled upstream of the flow path of the orifice plate to share a single orifice plate.

[0014] In some embodiments of the present invention, the needle valve one and the needle valve two are manual needle valves.

[0015] In some embodiments of the present invention, the orifice diameter of the throttling orifice plate is 0.5-0.8 mm.

[0016] A second aspect of the present invention is to provide a detection method for the online detection system of the OPC solenoid valve group of a steam turbine generator set as described above, comprising the following steps:

[0017] S1. Close the needle valve one, open the needle valve two, forcibly open the OPC solenoid valve, and observe the change in the pressure gauge reading. If the pressure gauge reading rises slowly or does not rise, it indicates that the OPC solenoid valve is malfunctioning. If the pressure gauge reading rises rapidly to full pressure, it indicates that the OPC solenoid valve is opening normally. Then proceed to step S2.

[0018] S2. Close the OPC solenoid valve. If the pressure gauge reading remains at full pressure or cannot drop to 0 MPa, it indicates that the OPC solenoid valve reset is abnormal. If the pressure gauge reading slowly drops to 0 MPa, it indicates that the OPC solenoid valve reset is normal.

[0019] In some embodiments of the present invention, in step S1:

[0020] a1) If the pressure gauge reading rises rapidly from 0 MPa to the system full pressure, it indicates that the OPC solenoid valve can be opened normally.

[0021] a2) If the pressure gauge reading rises slowly, it indicates that the OPC solenoid valve is not opening properly;

[0022] a3) If the pressure gauge reading does not rise, it indicates that the OPC solenoid valve is not properly opened.

[0023] In some specific embodiments of the present invention, in step S1:

[0024] a11) If the time it takes for the pressure gauge reading to rise to the full system pressure is ≤30s, it indicates that the OPC solenoid valve is open normally.

[0025] a21) If the time it takes for the pressure gauge reading to rise to the full system pressure is greater than 30 seconds, it indicates that the OPC solenoid valve has not opened properly.

[0026] In some embodiments of the present invention, in step S2:

[0027] b1) If the pressure gauge reading slowly decreases until it reaches 0 MPa, it indicates that the OPC solenoid valve has reset normally and is tight;

[0028] b2) If the pressure gauge reading cannot be restored to 0MPa, it indicates that the OPC solenoid valve is not tight after reset;

[0029] b3) If the pressure gauge reading maintains the full system pressure, it indicates that the OPC solenoid valve cannot be reset normally.

[0030] In some specific embodiments of the present invention, in step S2:

[0031] b11) If the pressure gauge reading drops to 0MPa in ≤30s, it indicates that the OPC solenoid valve resets normally and tightly;

[0032] b21) If the pressure gauge reading does not return to 0 MPa within >30 seconds, it indicates that the OPC solenoid valve is not tight after reset.

[0033] As described above, the online detection system and method for OPC solenoid valve groups in steam turbine generator sets of the present invention have the following beneficial effects:

[0034] (1) The OPC solenoid valve online detection system of the present invention has strong process reliability, accurate detection results, and strong feasibility of equipment modification.

[0035] (2) The OPC solenoid valve online detection system of the present invention can fundamentally solve the problem that the existing OPC solenoid valve cannot be detected online when the unit is running, thereby ensuring that the OPC solenoid valve can operate normally when the turbine is shedding load, reducing the occurrence of turbine overspeed accidents; at the same time, the OPC solenoid valve online detection system can ensure the accuracy of the reset after the OPC solenoid valve is activated, thereby quickly re-establishing the speed regulation pressure oil pressure, quickly starting the turbine to restore power and heat supply, especially for heating units, which is of great significance to ensuring that downstream steam users are protected from uncontrollable secondary accidents caused by steam supply interruption. Attached Figure Description

[0036] Figure 1 The diagram shows the overall structure of the online detection system for the OPC solenoid valve group of the steam turbine generator set according to the present invention.

[0037] Figure 2 This shows the normal oil unloading process after the online detection system for the OPC solenoid valve group of the steam turbine generator set of the present invention has been working.

[0038] Figure 3 This diagram shows the system flow for online testing of the OPC solenoid valve group online detection system for steam turbine generator sets according to the present invention.

[0039] Explanation of reference numerals in the attached figures:

[0040] 1. Oil inlet line; 2. Oil outlet line; 3. OPC solenoid valve assembly; 31. OPC solenoid valve; 32. Check valve; 33. Oil inlet branch; 34. Branch A; 35. Branch B; 36. Needle valve one; 37. Needle valve two; 38. Pressure gauge; 39. Orifice plate. Detailed Implementation

[0041] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0042] Please see Figure 1-3 It should be noted that the illustrations provided in this embodiment are only schematic representations of the basic concept of the present invention. Therefore, the drawings only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0043] Through research on internal thermal power enterprises, the inventors discovered that none of the current thermal power enterprises within the Sinopec system, such as Tianjin Petrochemical Thermal Power Department, Anqing Petrochemical Thermal Power Department, Yangzi Petrochemical Thermal Power Department, and Jinshan Petrochemical Thermal Power Department, possess an online detection system for OPC solenoid valves. This invention is the first of its kind. Furthermore, research on turbine speed control system manufacturers, such as Zhejiang Jieteyou and Purun Speed ​​Control, also revealed no online detection systems for OPC solenoid valves. Additionally, research on turbine manufacturers, such as Shanghai Turbine Plant of Shanghai Electric Group, also found no designs for online detection systems for OPC solenoid valves. Therefore, this invention is truly original.

[0044] See Figure 1-3 This invention provides an online testing system and method for OPC solenoid valve groups in steam turbine generator sets.

[0045] See Figure 1-2 An online detection system for an OPC solenoid valve assembly of a steam turbine generator set includes an OPC solenoid valve assembly 3. The OPC solenoid valve assembly 3 includes an oil inlet branch 33 connected to the oil inlet pipeline 1. The first end of the oil inlet pipeline 1 is connected to the GV hydraulic actuator on the steam turbine generator. A check valve 32 and an OPC solenoid valve 31 are sequentially arranged on the oil inlet branch 33. After the OPC solenoid valve 31, the oil inlet branch 33 is divided into branch A34 and branch B35. Branch A34 and branch B35 are respectively connected to the oil outlet pipeline 2 of the return oil pipeline of the steam turbine generator. A needle valve 36 is arranged on branch A34. A needle valve 37, a pressure gauge 38, and a throttling orifice plate 39 are sequentially arranged on branch B35. The working status of the OPC solenoid valve 31 is determined by controlling the opening and closing of the needle valve 36 and the needle valve 37 and combining the reading changes of the pressure gauge 38. When it is necessary to monitor the OPC solenoid valve 31 online, close needle valve 1 36, open needle valve 2 37, forcibly open the OPC solenoid valve 31, and judge the status of the OPC solenoid valve 31 by combining the reading changes of pressure gauge 38.

[0046] In some embodiments of the present invention, the signal transmission relationship between the OPC solenoid valve 31 and other devices is conventional and will not be described in detail here.

[0047] In some embodiments of the present invention, see [reference] Figure 1 and Figure 2 The OPC solenoid valve group 3 consists of at least two units, and each OPC solenoid valve group 3 is connected in parallel between the oil inlet line 1 and the oil outlet line 2.

[0048] The number of OPC solenoid valve assemblies 3 in this invention can be two, three, or more. See some embodiments of this invention. Figure 1 and Figure 2The OPC solenoid valve group 3 is configured with two valves. If one of the OPC solenoid valves 31 fails, when the turbine speed exceeds 103%, the other OPC solenoid valve 31 will operate to reduce the turbine speed.

[0049] In some embodiments of the present invention, the branches B35 of multiple OPC solenoid valve groups 3 are paralleled upstream of the flow path of the orifice plate 39 to share a single orifice plate 39.

[0050] In some embodiments of the present invention, the orifice diameter of the throttling orifice plate 39 is 0.5 mm.

[0051] In some embodiments of the present invention, the needle valve 36 and the needle valve 37 are manual needle valves.

[0052] See Figure 1-3 This embodiment also provides a detection method for an online detection system of OPC solenoid valve group in a steam turbine generator set, including the following steps:

[0053] S1. Close the needle valve 36 and open the needle valve 37 to forcibly open the OPC solenoid valve 31. Observe the change in the reading of the pressure gauge 38. The reading of the pressure gauge 38 rises rapidly to the full system pressure, indicating that the OPC solenoid valve 31 is open normally. The time for the reading of the pressure gauge 38 to rise to the full system pressure is 25 seconds.

[0054] S2. Close the OPC solenoid valve 31. The pressure gauge 38 reading slowly drops to 0 MPa, indicating that the OPC solenoid valve 31 has reset normally and is airtight. The time for the pressure gauge 38 reading to drop to 0 MPa is 25 seconds.

[0055] In some embodiments of the present invention, the detection method of the online detection system for the OPC solenoid valve group of a steam turbine generator set includes the following steps:

[0056] S1. Close the needle valve 36 and open the needle valve 37 to forcibly open the OPC solenoid valve 31. Observe the change in the reading of the pressure gauge 38. The reading of the pressure gauge 38 rises rapidly to the full system pressure, indicating that the OPC solenoid valve 31 is open normally. The time for the reading of the pressure gauge 38 to rise to the full system pressure is 25 seconds.

[0057] S2. When the OPC solenoid valve 31 is closed, the pressure gauge 38 maintains full pressure, indicating that the OPC solenoid valve 31 cannot reset normally, and therefore the OPC solenoid valve 31 is faulty and needs to be replaced.

[0058] In some embodiments of the present invention, the detection method of the online detection system for the OPC solenoid valve group of a steam turbine generator set includes the following steps:

[0059] S1. Close the needle valve 36 and open the needle valve 37 to forcibly open the OPC solenoid valve 31. Observe the change in the reading of the pressure gauge 38. The reading of the pressure gauge 38 rises rapidly to the full pressure, indicating that the OPC solenoid valve 31 is open normally. The time for the reading of the pressure gauge 38 to rise to the full system pressure is 25 seconds.

[0060] S2. If the pressure gauge 38 reading cannot return to 0MPa within 40 seconds after closing the OPC solenoid valve 31, it indicates that the OPC solenoid valve 31 is not tight after reset, and is therefore determined to be faulty and needs to be replaced.

[0061] In some embodiments of the present invention, the detection method of the online detection system for the OPC solenoid valve group of a steam turbine generator set includes the following steps: closing the needle valve 36, opening the needle valve 37, forcibly opening the OPC solenoid valve 31, and observing the change in the reading of the pressure gauge 38; if the pressure gauge 38 does not rise, it indicates that the OPC solenoid valve 31 is not properly opened, and therefore the OPC solenoid valve 31 is faulty and needs to be replaced.

[0062] In some embodiments of the present invention, the detection method of the online detection system for the OPC solenoid valve group of a steam turbine generator set includes the following steps: closing the needle valve 36, opening the needle valve 37, forcibly opening the OPC solenoid valve 31, and observing the change in the reading of the pressure gauge 38; if the time for the pressure gauge 38 reading to rise is 45s, it indicates that the OPC solenoid valve 31 has not opened normally, and therefore the OPC solenoid valve 31 is faulty and needs to be replaced.

[0063] In some embodiments of the present invention, there are at least two OPC solenoid valve groups 3, and the branches B35 of multiple OPC solenoid valve groups 3 are parallel upstream of the flow path of the orifice plate 39 to share a single orifice plate 39. To test other OPC solenoid valves 31, the needle valve 36 on the branch A34 corresponding to the corresponding OPC solenoid valve 31 is closed, and the needle valve 37 on the corresponding branch B35 is opened, forcibly opening the corresponding OPC solenoid valve 31. The oil in the inlet line 1 flows to the inlet branch 33, then to the branch B35 corresponding to the OPC solenoid valve 31, and flows through the flow path of the orifice plate 39 to the outlet line 2. The change in the pressure gauge 38 is observed, and the OPC solenoid valve 31 is determined to need replacement based on the above testing method.

[0064] In some embodiments of the present invention, in the non-detection state, the needle valve 36 is in the open state and the needle valve 37 is in the closed state, and the steam turbine resumes normal operation.

[0065] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. An online detection system for OPC solenoid valve groups in a steam turbine generator set, characterized in that, The online detection system for the OPC solenoid valve group of the steam turbine generator set includes an OPC solenoid valve group (3). The OPC solenoid valve group (3) includes an oil inlet branch (33) connected to the oil inlet pipeline (1). The first end of the oil inlet pipeline (1) is connected to the GV hydraulic actuator on the steam turbine generator. A check valve (32) and an OPC solenoid valve (31) are sequentially installed on the oil inlet branch (33). After the OPC solenoid valve (31), the oil inlet branch (33) is divided into branch A (34) and branch B. (35) The branch A (34) and the branch B (35) are respectively connected to the oil outlet pipeline (2) of the steam turbine generator return oil pipeline. A needle valve (36) is installed on the branch A (34), and a needle valve (37), a pressure gauge (38) and a throttling orifice plate (39) are installed on the branch B (35) in sequence. The working status of the OPC solenoid valve (31) is determined by controlling the opening and closing of the needle valve (36) and the needle valve (37) and combining the reading changes of the pressure gauge (38).

2. The online detection system for OPC solenoid valve group of steam turbine generator set according to claim 1, characterized in that: There are at least two OPC solenoid valve groups (3), and each OPC solenoid valve group (3) is connected in parallel between the oil inlet line (1) and the oil outlet line (2).

3. The online detection system for OPC solenoid valve group of steam turbine generator set according to claim 2, characterized in that: Branches B (35) of multiple OPC solenoid valve assemblies (3) are paralleled upstream of the flow path of the orifice plate (39) to share a single orifice plate (39).

4. The online detection system for OPC solenoid valve group of steam turbine generator set according to claim 1, characterized in that: The needle valve one (36) and needle valve two (37) are manual needle valves.

5. The online detection system for OPC solenoid valve group of steam turbine generator set according to claim 1, characterized in that: The orifice diameter of the throttling orifice plate (39) is 0.5-0.8 mm.

6. A detection method for an online detection system for OPC solenoid valve groups of a steam turbine generator set as described in any one of claims 1-5, characterized in that: Includes the following steps: S1. Close the needle valve one (36), open the needle valve two (37), forcibly open the OPC solenoid valve (31), and observe the change in the reading of the pressure gauge (38). If the reading of the pressure gauge (38) rises slowly or does not rise, it indicates that the OPC solenoid valve (31) is malfunctioning. If the reading of the pressure gauge (38) rises rapidly to full pressure, it indicates that the OPC solenoid valve (31) is opening normally. Then, proceed to step S2. S2. Close the OPC solenoid valve (31). If the pressure gauge (38) reading remains at full pressure or cannot drop to 0 MPa, it indicates that the OPC solenoid valve (31) is resetting abnormally. If the pressure gauge (38) reading slowly drops to 0 MPa, it indicates that the OPC solenoid valve (31) is resetting normally.

7. The detection method of the online detection system for the OPC solenoid valve group of a steam turbine generator set according to claim 6, characterized in that, In step S1: a1) If the pressure gauge (38) reading rises rapidly from 0 MPa to the total system pressure, it indicates that the OPC solenoid valve (31) can be opened normally; a2) If the pressure gauge (38) reading rises slowly, it indicates that the OPC solenoid valve (31) is not properly opened; a3) If the pressure gauge (38) reading does not rise, it indicates that the OPC solenoid valve (31) is not properly opened.

8. The detection method of the online detection system for the OPC solenoid valve group of a steam turbine generator set according to claim 7, characterized in that, In step S1: a11) If the time it takes for the pressure gauge (38) reading to rise to the total system pressure is ≤30s, it indicates that the OPC solenoid valve (31) is open normally; a21) If the time it takes for the pressure gauge (38) reading to rise to the total system pressure is >30s, it indicates that the OPC solenoid valve (31) is not properly opened.

9. The detection method of the online detection system for the OPC solenoid valve group of a steam turbine generator set according to claim 6, characterized in that, In step S2: b1) If the pressure gauge (38) reading slowly decreases until it reaches 0 MPa, it indicates that the OPC solenoid valve (31) has reset normally and is tight; b2) If the pressure gauge (38) reading cannot be restored to 0MPa, it indicates that the OPC solenoid valve (31) is not tight after reset; b3) If the pressure gauge (38) reading maintains the full system pressure, it indicates that the OPC solenoid valve (31) cannot be reset normally.

10. The detection method of the online detection system for the OPC solenoid valve group of a steam turbine generator set according to claim 6, characterized in that, In step S2: b11) If the pressure gauge (38) reading drops to 0 MPa in ≤30s, it indicates that the OPC solenoid valve (31) has reset normally and is tight; b21) If the pressure gauge (38) reading does not return to 0 MPa within >30s, it indicates that the OPC solenoid valve (31) is not tight after reset.

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