JPS6311100A - Diagnostic device for trouble of governor - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to a speed governor failure diagnosis device for diagnosing abnormal operating conditions of a speed governor used in a prime mover of a power generation plant. It is.

(Prior Art) Speed governors used in power generation plants: (1) Adjust the rotational speed of the generator to avoid parallel connection to the power grid.

(2) Adjust the load to keep the grid frequency constant when connected to the power grid.

(3) When a load shedding occurs, the increase in rotational speed of the generator is kept within the specified range.

It plays such an important role.

In order to supply stable, high-quality power, a high-performance, highly reliable speed governor is required. However, since the final stage of the governor has mechanically movable parts, the system as a whole has more problems than other devices.

However, with a lightning generator that has a very small capacity compared to the capacity of the power system to which it is connected, even if the speed governor operates abnormally during grid connection, it will not cause power fluctuations and will not be noticed. There is. If the governor is in such a state and disconnected from the power grid due to an external accident, this will immediately appear as an abnormal rotation speed of the generator, which will cause transient stress on the generator and the entire power plant. may cause damage to the equipment.

At hydroelectric power plants, which are often operated unmanned and located in mountainous areas with inconvenient transportation, it is necessary to detect abnormalities in the power generation equipment so that abnormal conditions can be discovered as early as possible and appropriate measures can be taken. be. As mentioned above, detection of abnormal operation of the speed governor is particularly important, and recently there has been a strong demand for a fault diagnosis device.

(Problems to be Solved by the Invention) The present invention provides a speed governor that performs failure diagnosis by monitoring whether the functions of the speed governor used in the prime mover of a power generation plant operated in parallel are functioning properly. The purpose is to provide a fault diagnosis device for

[Structure of the invention]

(Means for Solving the Problems) A failure diagnosis device for a speed governor according to the present invention is provided with a generator, a prime mover that drives the generator, and a prime mover that sets the rotational speed of the generator. Ru speed 7! ! Parallel operation detection for detecting whether or not this power generation plant is operating in parallel with an electric power system in a power generation plant equipped with a setting device and a speed governor that controls a load limit setting device that limits the output of the prime mover. a speed detector for detecting the rotational speed of the generator, a speed setting position detector for detecting the speed setting position of the speed setting device, and a load limiter for detecting the load limit setting position of the load limit setting device. comprising a setting position detector, an action change amount detector for detecting an action change amount of a mechanically movable part of the final stage of the speed governor, and a comparison determination means,
Under the situation that 11 parallel operations are occurring between the power generation plant and the electric power system as detected by the parallel operation detector, the comparison determination means has the following functions a to C. A failure diagnosis device for a speed governor, which is characterized by:

a) Based on the rotational speed of the generator detected by the speed detector and the amount of change in the action of the mechanically movable part of the final stage of the speed governor detected by the amount of action change detector, compares the state of change, and issues an alarm signal if the states of change are not the same.

b) the speed setting position of the IIn speed setting device detected by the speed setting position detector and the action change m;
The operation change L0 of the mechanically movable part of the final stage of the speed governor detected by the detector is compared with the change L0 (Then, the state of these changes is compared, and if the states of change are not the same, an alarm signal is issued. Output.

C) The load limit setting position of the load limit setter detected by the load limit setting position detector and the mechanically movable part of the final stage of the eleventh speed governor detected by the action change amount detector. The state of these changes is compared based on the effect of the change in the state of change, and an alarm signal is output if the states of change are not the same.

(Function) The fault diagnosis device for a speed governor according to the present invention uses a parallel operation detector to detect that a power generation plant is operating in parallel with the electric power system, and determines the rotational speed of the generator and the adjustment. The operation of each set position of the speed setter and load limit setter of the speed machine is detected by each detector, and the state of each change in the detected rotational speed, speed setting position, and load limit setting position is detected. , j detected by the action change detector
jff record The state of change in the action change m of the mechanical movable part of the final stage of the speed governor is compared by a comparison judgment means, and based on whether the states of change are the same, abnormal operation of the speed governor is determined. Detects and outputs a field signal.

(Embodiment) FIG. 1 is a block diagram showing an embodiment in which the present invention is used in a hydroelectric power plant.

This water horn power generation plant uses a generator 20 and this power generation!
The water turbine 21 that drives the water turbine 1120, the speed governor 22 that is installed on the water turbine 21 and sets the rotation speed of the generator 20, the water flow regulator 23 that adjusts the amount of water flowing into the water turbine 21, and the power system. It is equipped with a parallel-on circuit breaker 24 used for on-on operation.

The speed governor 22 is a mechanical type, and includes a speed detection section, a s''-bo motor 12, a pressure distribution valve, a restoring mechanism, a speed adjustment mechanism,
and a load limiting mechanism.

The speed detection section converts the rotational speed into vertical movement by the action of the centrifugal saw applied to the pendulum 11 and the spring 16.

When the water turbine 21 is in an equilibrium state with a certain load, the floating lever 15 is in the horizontal position of p, r, co, and the piston 14 of the pressure distribution valve is in the neutral position, so that the pressure oil is cut off.

Now when the load decreases, the rotational speed increases and Pensulam 1
1 opens and Po goes up to Pl. At this time, since Ro is a fixed point, Go goes down to cl, the piston 14 goes down, pressure oil enters from the left side of the servo motor 12, the servo motor piston 13 moves to the right, and the water inlet of the water volume adjustment 2S23 Reduce opening.

When the water mouth opening becomes smaller, the water turbine output decreases and the rotational speed decreases, but due to the inertia of the power generator 120, it takes a considerable amount of time to reduce to the specified rotation. If the nervomotor 12 is moved in the opening direction during this time, the output will be reduced too much, so the restoring mechanism raises R8 to R1, and when the water spout reaches an appropriate opening degree, the cl is returned to the neutral position C8. When the speed gradually decreases and Pl returns to Po, R1 is gradually changed to R8 by the dashbot 17 of the righting mechanism, and the speed settles to approximately the same as the initial speed, resulting in a new equilibrium state. The behavior when the load increases is the opposite.

To adjust the output during parallel operation, the position of Ro is moved up and down by the speed adjustment mechanism. To operate below a certain output regardless of frequency, a load limiting mechanism is used to
Press the upper limit of the co position.

Further, an electric speed governor is also used in a power generation plant, but the parts other than the servo motor 12 and the pressure distribution valve are replaced with electric circuits.

The fault diagnosis device for a speed governor according to this embodiment includes a parallel operation detector 8 that detects whether or not a power generation plant is performing parallel operation based on the operation of a parallel circuit breaker 24; a speed detector 4 that detects the rotational speed of the speed governor 2;
a speed setting position detector 5 for detecting the position of R8 moved by the speed adjusting mechanism of speed governor 22, and a load limit setting position detector '56 for detecting the position of C6 set by the load limiting mechanism of the speed governor 22; The servo motor 12 is provided with an action change detector 7 for detecting the amount of action change of a mechanically movable part of the servo motor 12, and a comparison determination means 3.

FIG. 2 is a flowchart 1! showing an embodiment of the comparison/judgment means according to the present invention. - It is.

The comparison/determination means 3 determines whether or not this power plant is performing a parallel operation based on a signal indicating the presence or absence of a parallel operation of the power plant detected by the parallel operation detector 8 .

It is assumed that the power generation plans 1 to 1 are currently operating in parallel with the grid. The comparison/determination means 3 determines whether the rotational speed of the power generation f120 detected by the speed detector 4 is equal to a predetermined value, and if it is not equal, the change in the rotational speed of the generator 20 and the effect change are detected by the detector 7. compares the amount of change in action detected by , and outputs an alarm signal if the states of change are not the same.

Further, the comparison determination means 3 determines whether the rotational speed of the generator 20 detected by the speed detector 4 is close to a predetermined value, or if the change in the rotational speed of the generator 20 and the change in the amount of change in action are different. In the same case, it is determined whether the speed setting mechanism is operating based on the speed setting position R6 detected by the speed setting position detector 5, and if it is operating, the speed setting position R8 and the change in the effect are determined. It compares the two companies and outputs an alarm signal if the state of change is not the same.

Then, when the speed setting position R6 is not operating, or when the speed setting position R6 and the change in the amount of change in action are the same, the comparison judgment means 3 detects the position detected by the load limit setting position detector 6. Based on the load limit setting position C8, it is determined whether the load limit mechanism is operating, and if it is operating, the load limit setting position C8 is compared with the amount of change in the action, and the state of the change is determined. Outputs an alarm signal if they are not the same. If the load limiting mechanism is not operating, return to the beginning and repeat the above procedure.

゛Figure 3 is a graph showing the system frequency (or rotational speed of the generator 200) and the movement of the servo motor.

In the section 31, the mechanical movable part of the servo motor 12 is also operating in the closing direction as the system frequency (or the rotational speed of the generator 20) increases, and can be determined to be normal.

In the section 320, hunting occurs even though the system frequency (or rotational speed of the generator 20) is stable, and it can be determined that there is an abnormality.

The section 33 indicates the system frequency (or the generator 200
Even though the rotational speed) has changed, servo motor 1
The mechanical moving parts of 2 are not moving. This can be determined to be an abnormality in the mechanical lock, piping, or electrical part.

(Effects of the Invention) According to the present invention, the rotation speed of the generator, the movement of the speed setting value of the speed governor, and the movement of the load limit setting value of the speed governor are monitored, and the state of these changes and the w4 speed are monitored. By comparing the state of change in the amount of change in the action of the mechanical moving parts of the final stage of the machine, it is possible to detect a failure of the speed governor during parallel operation with the power system of the power generation plant. , it can contribute not only to conservative aspects but also to the stabilization of the entire power generation system.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment in which the present invention is used in a hydroelectric power plant. FIG. 2 is a flowchart showing one embodiment of the function of the comparison and determination means according to the present invention. FIG. 3 is a graph showing the system frequency and the movement of the servo motor. 3... Comparative judgment means, 4! ...Speed detector, 5...
Speed setting position detector, 6... Load limit setting position detector, 7... Action change amount detector, 8... Parallel operation detector, 20... Generator, 21... Water turbine, 22...Speed governor, 23...Water flow governor, 24...Parallel entry circuit breaker. Applicant's agent Mr. Sato - Figure 2

Claims (1)

[Scope of Claims] A generator, a prime mover for driving the generator, a speed setting device provided on the prime mover for setting the rotational speed of the generator, and a load limit setting device for limiting the output of the prime mover. In a power generation plant equipped with a speed governor, a parallel operation detector detects whether or not this power generation plant is operating in parallel with an electric power system, and a speed detector detects the rotational speed of the generator. , a speed setting position detector for detecting the speed setting position of the speed setting device; a load limit setting position detector for detecting the load limit setting position of the load limit setting device; an action change amount detector for detecting an action change amount of a movable part, and a comparison determination means, and the power generation plant and the electric power system are operated in parallel, which is detected by the parallel operation detector. Under the situation that the comparison judgment means is
A speed governor failure diagnosis device characterized by having the following functions. a) Based on the rotational speed of the generator detected by the speed detector and the amount of change in the action of the mechanically movable part of the final stage of the speed governor detected by the amount of action change detector, compare the states of change, and output an alarm signal if the states of change are not the same. b) the speed setting position of the speed setter detected by the speed setting position detector; and the amount of change in action of the mechanically movable part of the final stage of the speed governor detected by the amount of change in action detector; The state of these changes is compared based on the state of change, and an alarm signal is output if the states of change are not the same. c) the load limit setting position of the load limit setter detected by the load limit setting position detector and the action of the mechanically movable part of the final stage of the speed governor detected by the action change amount detector; The state of these changes is compared based on the amount of change, and if the states of change are not the same, an alarm signal is output.