KR102169666B1 - Method for testing quick closing of actuator for power plant - Google Patents

Abstract

The quick closing test method of an actuator for a power plant that closes the supply flow path of steam supplied to the turbine in an emergency situation of a power plant according to the present invention is a piston connected to a valve that selectively opens and closes the supply flow path. Comprising a piston and a cylinder having a rod and a piston head, (a) setting the position of the piston head to the first test position by setting the condition of the closed state of the supply channel, (b) supplying the fluid to the inside of the cylinder The step of setting the flow path open condition and setting the position of the piston head moved from the first test position to the second test position, (c) discharging the fluid to the outside of the cylinder and moving the piston from the second test position to the first test position. And calculating a movement time for a displacement value of the piston head moved from the second test position to the first test position in the step of moving the head and step (d) (c).

Description

Quick closing test method of actuator for power plant {METHOD FOR TESTING QUICK CLOSING OF ACTUATOR FOR POWER PLANT}

The present invention relates to a quick closing test method of an actuator for a power plant, and more particularly, a power generation capable of testing quick closing for quickly closing a supply passage of steam supplied to a turbine in an emergency situation of a power plant under operating conditions of a power plant. It relates to a quick closing test method of a small actuator.

Power plants are equipped with facilities that generate power, and are classified into hydropower, thermal power, nuclear power, wind power, geothermal power, and tidal power plants, depending on the energy method. Among the various power plants described above, a thermal power plant and a nuclear power plant typically generate electric power by operating a turbine according to the supply of steam. Such thermal power plants and nuclear power plants include a turbine governor control system device for controlling steam flowing into the high-pressure turbine and the low-pressure turbine and steam discharged through each of the turbines, that is, controlling the amount of steam.

Here, the turbine governor control system device includes turbine valves that control the pressure and flow rate of steam, and an actuator for a power plant connected to the turbine valves to provide driving force to the turbine valves. An actuator for a power plant is composed of a cylinder and a piston connected to a turbine valve, and the piston reciprocates according to the supply of fluid such as hydraulic oil into the cylinder and discharge of the fluid from the inside of the cylinder. That is, the piston reciprocates according to the supply and discharge of the fluid to the cylinder to provide a driving force to the turbine valve.

In detail, the relationship between the operation of the actuator for a power plant and the turbine valve is that when fluid is supplied to the cylinder, the supply flow path through which steam is supplied to the turbine becomes an opening that is opened according to the operation of the turbine valve according to the movement of the piston, and the cylinder When fluid is discharged from, the supply flow path is closed according to the operation of the turbine valve according to the movement of the piston. In addition, the relationship between the operation of the actuator for the power plant and the turbine valve prevents the inflow of steam supplied to the turbine in an emergency situation in the power plant, for example, when an abnormality occurs in the turbine and/or when steam exceeding the required amount of steam flows into the turbine. Works to do. More specifically, the actuator for a power plant is operated by quick closing, in which the hydraulic oil in the cylinder is rapidly discharged while the turbine valve opens the supply flow path and closes the supply flow path with the turbine valve.

On the other hand, the actuator for a power plant needs to be maintained periodically or when a problem occurs in the power plant. Maintenance of such power plant actuators is performed by disassembling and assembling major parts such as cylinders and pistons. After maintenance of the actuator for the power plant, the operational reliability of the actuator must be verified. In detail, tests such as the moving displacement value and time of the piston between opening and closing when operating the power plant actuator, as well as testing the moving displacement value and time of the piston during quick closing operation are also performed. In particular, in a power plant, it is an important issue to prevent malfunction of the turbine, so a quick closing test of an actuator for a power plant is important.

However, the quick closing test of the conventional power plant actuator is performed in a state where the turbine valve is connected substantially in the same manner as the operating conditions of the power plant. That is, in the conventional quick closing test of an actuator for a power plant, after maintenance of the actuator for a power plant, a quick closing test is performed after connecting the actuator for the power plant and the turbine valve. After maintenance of the power plant actuator again, there is a problem in that a process of combining the power plant actuator and the turbine valve occurs, thereby increasing the maintenance time.

Republic of Korea Patent Publication No. 2004-0100613: Turbine control system in a power plant

It is an object of the present invention to provide a quick closing test method of an actuator for a power plant capable of performing a quick closing test only with the actuator for a power plant after virtually setting the condition of an actuator for a power plant used in connection with a valve in a power plant.

The means for solving the problem is a method for a quick closing test method of an actuator for a power plant for closing a supply flow path of steam supplied to a turbine in an emergency situation of a power plant according to the present invention, wherein the actuator for the power plant is the supply flow path Comprising a piston and a cylinder having a piston rod and a piston head connected to a valve that selectively opens and closes, (a) setting the position of the piston head to a first test position by setting the supply flow path as a closed state condition And, (b) supplying a fluid to the inside of the cylinder to set a condition for an open state of the supply passage and setting a position of the piston head moved from the first test position to a second test position, and (c) Discharging the fluid to the outside of the cylinder to move the piston head from the second test position to the first test position, and (d) from the second test position to the first test position in the step (c). It is made by a quick closing test method of an actuator for a power plant, comprising the step of calculating a movement time for a displacement value of the piston head to be moved.

Here, step (a) may be set as a condition in which the valve closes the supply passage while the power plant is operating, and the valve is virtually connected to the piston rod.

The first test position may include spaced apart from one side of the cylinder at a predetermined interval when the valve is virtually connected to the piston rod.

The first test position may be set by disposing a spacer having a predetermined thickness at the free end of the piston rod.

In the step (c), the second test position may include any one of a contact position in which the piston head contacts the other side of the cylinder and a spaced position spaced apart from the other side of the cylinder at a predetermined interval. .

The step (d) may calculate a quick closing time for the piston head to move from the second test position to the first test position where the valve virtually connected to the piston rod closes the supply passage.

In addition, the quick closing test method of the actuator for a power plant may further include (e) analyzing the quick closing time calculated in step (d).

The quick closing time is a first quick closing time calculated when the fluid accommodated in the cylinder at the second test position is discharged to the outside of the cylinder, and the fluid discharged during the first quick closing time from the first quick closing time It may include a second quick closing time calculated until a relatively small amount of fluid is discharged to reach the first test position.

The second quick closing time may be caused by a change in the cross-sectional area of the fluid discharged from the cylinder.

Details of other embodiments are included in the detailed description and drawings.

The effect of the quick closing test method of an actuator for a power plant according to the present invention is that after disassembly and assembly for maintenance of the actuator for a power plant, a condition in which the valve is connected to the piston virtually, such as the operating condition of the power plant, is set to operate in a power plant emergency situation. Since the quick closing test of the actuator for a power plant can be performed, the time required for the quick closing test of the actuator for the power plant before the power plant is operated can be reduced and operation reliability can be checked more quickly.

1 is a schematic configuration diagram of a general power plant,
2 is a control block diagram for a quick closing test apparatus of an actuator for a power plant according to an embodiment of the present invention;
3 is a configuration diagram for a quick closing test of an actuator for a power plant according to an embodiment of the present invention,
4 is an enlarged cross-sectional view of a region IV shown in FIG. 3;
5 is an enlarged cross-sectional view in which the piston head shown in FIG. 4 is positioned at a second test position;
6 is a flowchart of a quick closing test method of an actuator for a power plant according to an embodiment of the present invention;
7 is a conceptual configuration diagram of a stroke in a quick closing test method for an actuator for a power plant according to an embodiment of the present invention;
8 is a graph calculated in a quick closing test of an actuator for a power plant according to an embodiment of the present invention.

Hereinafter, a quick closing test method of an actuator for a power plant according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

Prior to the description, it is noted in advance that the quick closing test method of an actuator for a power plant according to an embodiment of the present invention can be applied to actuators for power plants of various structures manufactured by a plurality of manufacturers.

1 is a schematic configuration diagram of a general power plant.

A power plant is basically a facility that generates power by rotating a turbine (T). Various facilities or devices are arranged in the power plant for providing rotational driving force to the turbine T. Thermal and nuclear power plants, for example, use steam to provide rotational drive power to the turbine T. This steam is supplied and cut off to the supply channel S connected to the turbine T by the selective operation of the valve V. Here, the valve (V) for selectively opening and closing the supply passage (S) is connected to the power plant actuator (A). That is, the valve V selectively opens and closes the supply passage S according to the operation of the power plant actuator A. In detail, the piston (P) of the actuator (A) for a power plant connected to the valve (V) is reciprocally moved according to the fluid (F; see Fig. 5) supplied to and discharged from the cylinder (C) to open the supply passage (S) It provides a driving force to the valve V between the closed position closing and the open position opening.

2 is a control block diagram for a quick closing test apparatus of an actuator for a power plant according to an embodiment of the present invention, FIG. 3 is a configuration diagram for a quick closing test of an actuator for a power plant according to an embodiment of the present invention, and FIG. An enlarged cross-sectional view of the region IV shown in FIG. 3, and FIG. 5 is an enlarged cross-sectional view of the piston head shown in FIG. 4 positioned at a second test position.

2 to 5, the quick closing test apparatus 1 of the actuator A for a power plant according to an embodiment of the present invention includes a displacement sensor 10, an operation unit 20, a control unit 40, and a display. It includes a unit 50, a storage unit 70, and a spacer 90. The quick closing test apparatus 1 of the actuator A for a power plant according to an embodiment of the present invention tests the quick closing of the actuator A for a power plant under the same conditions as the actual operating conditions of the power plant. In detail, the setting of the same conditions as the operating conditions of the power plant is a condition in which the valve V and the piston P are virtually connected, such as the piston P and the valve V of the power plant actuator A are interconnected.

The power plant actuator (A) includes a cylinder (C), a piston (P), a spring (E) and a spring housing (H). The cylinder (C) forms a space for receiving the fluid (F) for providing hydraulic force to the piston (P). The piston (P) is a valve (V), that is, a piston rod (P1) connected to a virtual valve (V) in an embodiment of the present invention and a piston head connected to the piston rod (P1) to be accommodated in the cylinder (C). (P2) is included. The piston head P2 divides the inside of the cylinder C into a pressurized space in which the fluid F is accommodated and a negative pressure space in which the fluid F is not supplied. The piston head P2 reciprocates within the cylinder C according to the fluid pressure of the fluid F supplied to the inside of the cylinder C and discharged from the inside of the cylinder C. The spring (E) provides an elastic force so that the piston (P) moves to a position where the supply passage (S) is closed when the fluid (F) contained in the cylinder (C) is discharged to the outside. The spring housing (H) accommodates the spring (E). The spring housing (H) is disposed on the opening side of the housing body (H1) and the housing body (H1) to form an accommodation space for accommodating the spring (E), depending on the movement of the piston (P) or the elastic force of the spring (E). It includes a moving housing cover (H2).

For a quick closing test of the actuator A for a power plant according to an embodiment of the present invention, the actuator A for a power plant, which has been maintained, is mounted on the base B for maintenance as shown in FIG. 3. The maintenance base (B) is a first base (B1) supported on the ground and a second base (B2) arranged between the power plant actuator (A) and the first base (B1) to support the power plant actuator (A). Includes.

Here, a spacer 90 having a predetermined thickness for positioning the piston P at the first test position T1 is disposed between the free end of the piston rod P1 and the first base B1. The thickness of the spacer 90 is determined according to the requirements of the power plant or the design criteria of the actuator A for the power plant. In this way, the spacer 90 is arranged to secure a certain distance between one side of the cylinder C and the piston head P2, that is, positioning the piston head P2 at the first test position T1 is a valve ( It is set as the condition connected with V). In detail, when the valve (V) is located in the closed position to close the supply channel (S) under actual power plant operating conditions, when one side of the cylinder (C) and the piston head (P2) contact, the actuator (A) for power plant Cylinder (C) because at least one of the cylinder (C) and the piston head (P2) may be damaged by a collision between one side of the cylinder (C) and the piston head (P2) according to the elastic force of the spring (E) during closing. One side and the piston head P2 are disposed at a predetermined interval. In order to meet such a power plant operating condition, as an embodiment of the present invention, as shown in FIG. 4, a spacer 90 is disposed to set a condition in which the valve V is connected to the piston head P2. It is placed in the first test position T1.

During the quick closing test of the actuator A for a power plant according to an embodiment of the present invention, the displacement sensor 10 is connected to the piston P to detect a displacement value according to the movement of the piston P. For example, the displacement sensor 10 detects the displacement value of the first test position T1 when the piston head P2 is positioned at the first test position T1 as shown in FIG. 4. And, as shown in Figure 5, the displacement sensor 10 is the second test position (T2) of the piston head (P2) when the virtually connected valve (V) is located in the open position to open the supply passage (S). ) To detect the displacement value. Meanwhile, as an embodiment of the present invention, the second test position T2 of the piston head P2 is shown in FIG. 5 as being in contact with the other side of the cylinder C, but is not limited thereto and Can be located.

The calculation unit 20 calculates a movement time when the piston head P2 is moved from the second test position T2 to the first test position T1 by quick closing. Specifically, when the unillustrated fast acting solenoid valve is excited and the fluid F accommodated in the cylinder C is discharged to the outside, the operation unit 20 is the first at the second test position T2. The moving time of the piston head P2 moving to the test position T1 is calculated.

The control unit 40 outputs a graph of the displacement value of the piston head P2 as a control signal based on the detection signal provided from the displacement sensor 10 and the movement time calculated by the operation unit 20. The control unit 40 outputs a graph of the displacement value of the piston head P2 as a control signal and provides it to the display unit 50. The display unit 50 displays a graph of the displacement value of the piston head P2 on the display according to a control signal provided from the controller 40. The graph of the displacement value of the piston head P2 displayed on the display unit 50 may display the movement time for the displacement value of the piston head P2 according to the change of the position of the mouse or the input means. The storage unit 70 stores a displacement value sensed by the displacement sensor 10 and a movement time according to the movement of the piston head P2 calculated by the calculation unit 20. In addition, the storage unit 70 also stores a graph of the displacement value of the piston head P2 provided from the control unit 40.

Next, FIG. 6 is a flowchart of a quick closing test method of an actuator for a power plant according to an embodiment of the present invention, and FIG. 7 is a conceptual configuration diagram of a stroke in a quick closing test method of an actuator for a power plant according to an embodiment of the present invention. And Figure 8 is a graph calculated in the quick closing test of the actuator for a power plant according to an embodiment of the present invention.

With this configuration, a quick closing test method of the actuator A for a power plant according to an embodiment of the present invention is as follows.

First, the displacement sensor 10 is disposed to detect the displacement value according to the movement of the piston P (S10). In a virtually connected state with the valve V, the position of the piston head P2 is set to the first test position T1 by setting the condition of the closed state of the supply passage S (S30). As shown in Fig. 7, when the moving distance of the piston P is the actuator stroke and the moving distance of the valve V (including the virtual valve) is the valve stroke, the maximum actuator stroke between both sides of the actual cylinder C Becomes L1 and the valve stroke becomes L3. Here, the power plant actuator (A) that is actually operated in the power plant is connected to the valve (V), and the power plant actuator (A) in the power plant operating condition is between the first test position (T1) and the second test position (T2). It becomes the actuator stroke L2 which reciprocates.

The fluid (F) is supplied to the inside of the cylinder (C) to set the condition of the supply passage (S) open, and the position of the piston head (P2) moved from the first test position (T1) to the second test position (T2). Set to (S50). Here, the second test position T2 may be set to a position at a predetermined distance or in contact with the other side of the cylinder C according to the operating conditions of the power plant and/or the design conditions of the actuator A for the power plant.

Next, as an excitation signal is provided to the fast-acting solenoid valve, the fluid (F) contained in the cylinder (C) is discharged to the outside, and the piston head (P2) in the second test position (T2) is at the first test position (T1). ). (S70). Step S70 is a step of quick closing the actuator (A) for a power plant. When an excitation signal is provided to the fast acting solenoid valve as shown in Figs. 8A and 8B, the fast acting solenoid valve is prevented from mechanical movement. A corresponding delay time (D) occurs, and the power plant actuator (A) is quickly closed.

In step S70, the movement time for the displacement value of the piston head P2 according to the movement of the piston head P2 is calculated (S90). The graph of the movement time for the displacement value of the piston head P2 calculated in step S70 is analyzed (S110).

In step S110, the graph of the movement time relative to the displacement value of the piston head P2 is based on the movement of the piston head P2 from the second test position T2 to the first test position T1, that is, the movement of the piston P. Accordingly, the moving time between the open position and the closed position of the virtually connected valve V is analyzed. As shown in (b) of FIG. 8, the quick closing time (Q) is calculated from a graph of the movement time versus the displacement value of the piston (P).

Here, the quick closing time Q is divided into a first quick closing time Q1 and a second quick closing time Q2. The first quick closing time (Q1) is the time calculated when the fluid (F) received in the cylinder (C) at the second test position (T2) is discharged to the outside of the cylinder (C), and the second quick closing time (Q2) Is a time calculated from the first quick closing time Q1 to the first test position T1 by discharging relatively less fluid than the fluid F discharged during the first quick closing time Q1. The first quick closing time Q1 and the second quick closing time Q2 are generated by a change in the flow path cross-sectional area of the fluid F discharged from the cylinder C. That is, the first quick closing time Q1 and the second quick closing time Q2 are the fluid F discharged when the piston head P2 moves from the second test position T2 to the first test position T1. When the cross-sectional area of the flow path of) changes, it is relatively decreased. The point at which the first quick closing time Q1 is changed to the second quick closing time Q2 is referred to as a cushioning point CP. When described in detail with reference to FIGS. 7 and 8, the second quick closing time Q2 means a time for the piston head P2 to reach the first test position T1 from the cushioning point CP, at this time The actuator stroke is equal to L4.

Accordingly, after disassembling and assembling for maintenance of the power plant actuator, a quick closing test of the power plant actuator operating in case of a power plant emergency can be performed by setting the condition of virtually connecting the valve to the piston, such as the operating condition of the power plant. In addition, it is possible to quickly check the operation reliability while reducing the time required for the quick closing test of the actuator for the power plant before starting the power plant.

Although the embodiments of the present invention have been described with reference to the accompanying drawings above, those of ordinary skill in the art to which the present invention pertains can be implemented in other specific forms without changing the technical spirit or essential features of the present invention. It will be understandable. Therefore, it should be understood that the embodiments described above are illustrative and non-limiting in all respects. The scope of the present invention is indicated by the claims to be described later rather than the detailed description, and all changes or modified forms derived from the meaning and scope of the claims and the concept of equivalents thereof should be interpreted as being included in the scope of the present invention. do.

1: Quick closing test device of actuators for power plants
10: displacement sensor 20: calculation unit
40: control unit 90: spacer
A: Actuator for power plant C: Cylinder
P: piston rod P1: piston rod
P2: Piston head E: Spring
H: spring housing B: maintenance base
T1: 1st test position T2: 2nd test position
Q: Quick closing time Q1: First quick closing time
Q2: 2nd quick closing time

Claims (9)

In the quick closing test method of an actuator for a power plant for closing a supply flow path of steam supplied to a turbine in an emergency situation of a power plant,
The power plant actuator includes a piston and a cylinder having a piston rod and a piston head connected to a valve that selectively opens and closes the supply passage,
(a) setting the position of the piston head to a first test position by setting the supply passage in a closed state condition;
(b) supplying a fluid into the cylinder to set the condition of the supply passage in an open state, and setting a position of the piston head moved from the first test position to a second test position;
(c) discharging the fluid to the outside of the cylinder to move the piston head from the second test position to the first test position;
(d) calculating a movement time for a displacement value of the piston head moved from the second test position to the first test position in step (c),
Step (a) is a quick closing of an actuator for a power plant, characterized in that the valve is set to a condition in which the valve closes the supply flow path during operation of the power plant, and the valve is set to a condition in which the valve is virtually connected to the piston rod. (quick closing) test method.
delete The method of claim 1,
The first test position is a quick closing test method of an actuator for a power plant, characterized in that when the piston rod and the valve are virtually connected, spaced apart from one side of the cylinder at a predetermined interval.
The method of claim 1 or 3,
The first test position is set by disposing a spacer having a predetermined thickness at the free end of the piston rod.
The method of claim 3,
In the step (c), the second test position includes any one of a contact position in which the piston head contacts the other side of the cylinder and a spaced position spaced apart from the other side of the cylinder at a predetermined interval. Quick Closing Test Method for Power Plant Actuators
The method of claim 1,
The step (d) is characterized in that calculating a quick closing time for the piston head to move from the second test position to the first test position in which the valve virtually connected to the piston rod closes the supply passage. Quick closing test method for power plant actuators.
The method of claim 6,
The quick closing test method of the actuator for power plant,
(e) analyzing the quick closing time calculated in the step (d), the quick closing test method of an actuator for a power plant, further comprising.
The method of claim 7,
The quick closing time,
A first quick closing time calculated when the fluid contained in the cylinder at the second test position is discharged to the outside of the cylinder;
And a second quick closing time calculated from the first quick closing time until a fluid that is relatively less than the fluid discharged during the first quick closing time is discharged and reaches the first test position. Quick closing test method for power plant actuators.
The method of claim 8,
The second quick closing time is generated by a change in a cross-sectional area of a flow path of the fluid discharged from the cylinder.

Images