JPH0811000B2 - Governor failure diagnosis device - Google Patents

Description

Description: [Object of the Invention] (Industrial field of application) The present invention relates to a speed governor failure diagnosis device for diagnosing an abnormal operating state of a speed governor used as a prime mover of a power plant. Is.

(Prior Art) A governor used in a power generation plant (1) adjusts the rotation speed of the generator so that the speed governor is put in parallel with the power system.

(2) Adjust the load so that the system frequency is kept constant when connected to the power system.

(3) When the load is cut off, the increase in the rotation speed of the generator is suppressed within the specified range.

Etc. plays an important role.

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

However, in a generator with a very small capacity compared to the capacity of the connected power system, even if the governor malfunctions during grid connection, it will not cause power fluctuations, so you may not notice it. is there. When the governor is in such a state, if it is disconnected from the power system due to an external accident, etc., it immediately appears as an abnormal rotation speed of the generator, so transient stress is applied to the generator and the entire power plant. And sometimes damage the equipment.

In a hydroelectric power plant that is often operated unmanned in mountainous areas where traffic is inconvenient, it is necessary to detect abnormalities in the equipment so that abnormal conditions in power generation equipment can be detected as early as possible and appropriate processing can be performed. is there. As described above, it is particularly important for the speed governor to detect an abnormal operation, and recently, the appearance of a failure diagnosis device has been strongly demanded.

(Problems to be Solved by the Invention) The present invention is directed to a speed governor which monitors whether or not the function of a speed governor used as a prime mover of a power generation plant operated in parallel operates normally and performs a failure diagnosis. An object of the present invention is to provide a failure diagnosis device.

[Structure of Invention]

(Means for Solving Problems) A speed governor failure diagnosis apparatus according to the present invention is provided in a generator, a prime mover for driving the generator, and the prime mover.
In a power plant having a speed governor having a speed setter for setting the rotation speed of the generator and a load limit setter for limiting the output of the prime mover, the power plant performs parallel operation with the power system. A parallel operation detector that detects whether or not there is a speed detector that detects the rotation speed of the generator, a speed setting position detector that detects the speed setting position of the speed setting device, and a load limit setting device. A load limit setting position detector for detecting a load limit setting position; an action change amount detector for detecting an action change amount of a mechanical movable part at the final stage of the speed governor; and a comparison determining means. Under the circumstance that parallel operation between the power generation plant and the power system detected by the parallel operation detector is being performed, the comparison / determination means has the following functions a to c. To Failure diagnosis apparatus of the speed governor to butterflies.

a) Based on the rotation speed of the generator detected by the speed detector and the operation change amount of the mechanical movable part at the final stage of the speed governor detected by the operation change amount detector, The state of change is compared, and if the state of change is not the same, an alarm signal is output.

b) The speed setting position of the speed setting device detected by the speed setting position detector, and the action change amount of the mechanically movable part at the final stage of the speed governor detected by the action change amount detector. Based on the above, the states of these changes are compared, and if the states of the change are not the same, an alarm signal is output.

c) The load limit setting position of the load limit setting device detected by the load limit setting position detector, and the action of the mechanical movable part at the final stage of the speed governor detected by the action change amount detector. Based on the amount of change, the states of these changes are compared, and if the states of change are not the same, an alarm signal is output.

(Operation) A fault diagnosing device for a governor according to the present invention detects that a power plant is performing a parallel operation with a power system by a parallel operation detector, and detects the rotation speed of the generator and 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 detected rotation speed, the speed set position, and the state of each change of the load limit set position are detected. , The change state of the action change amount of the mechanical movable part of the final stage of the speed governor detected by the action change amount detector is compared by the comparison and determination means, and based on whether or not the change state is the same. , Detect abnormal operation of governor and output alarm signal.

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

This hydroelectric power plant consists of a generator 20 and this generator 20
The water turbine 21 that drives the
A speed governor 22 for setting the rotational speed of the water turbine, a water amount adjuster 23 for adjusting the amount of water flowing into the water turbine 21, and a parallel insertion breaker 24 used for parallel insertion operation with the power system.

The speed governor 22 is a mechanical type, and includes a speed detection unit, a servo motor 12, a pressure distribution valve, a restoring mechanism, a speed adjusting mechanism, and a load limiting mechanism. The speed detecting unit converts the rotational speed into vertical movement by the action of the centrifugal force applied to the pendulum 11 and the spring 16. When the turbine 21 is in an equilibrium state under a certain load, the floating lever 15 is in the horizontal position of P ₀ , R ₀ , C ₀ , the piston 14 of the pressure distribution valve is in the neutral position, and the pressure oil is cut off. .

Now when the load decreases, the rotation speed increases and the pendulum
11 opens and P ₀ goes up to P ₁ . At this time, since R ₀ is a fixed point, C ₀ goes down to C ₁ , the piston 14 goes down, pressure oil enters from the left side of the servomotor 12, the servomotor piston 13 moves to the right, and the water amount regulator Reduce the water outlet opening of 23. When the water opening is reduced, the turbine output decreases and the rotation speed decreases, but it takes a considerable time to reach the specified rotation due to the inertia of the generator 20. During this time so that the servo motor 12 is too lowered and the output moves in the closing direction, R ₀ by righting mechanism
Raise to R ₁ and when the water outlet reaches an appropriate opening, return C ₁ to the neutral position C ₀ . When the speed gradually decreases and P ₁ returns to P ₀ , R ₁ gradually becomes R ₀ by the dashpot 17 of the restoration mechanism.
Returning to the new equilibrium, the speed settles at about the same as the first. The behavior when the load increases is the opposite.

To adjust the output during parallel insertion operation, the speed adjustment mechanism moves the position of R ₀ up and down. To operate below a certain output regardless of frequency, the load limiting mechanism
Hold down the upper limit of C ₀ position.

Electric type speed governors are also used in power plants,
The parts other than the servo motor 12 and the pressure distributing valve are replaced with electric circuits.

The fault diagnosing device for a speed governor according to the present embodiment includes a parallel operation detector 8 for detecting whether the power plant is performing parallel operation based on the operation of the parallel breaker 24, and a generator 20. Is set by the speed detector 4 for detecting the rotation speed of the motor, the speed setting position detector 5 for detecting the position of R ₀ moved by the speed adjusting mechanism of the speed governor 22, and the load limiting mechanism of the speed governor 22. The load limit set position detector 6 for detecting the position of C ₀ , the action change amount detector 7 for detecting the action change amount of the mechanically movable part of the servo motor 12, and the comparison / determination means 3 are provided. .

FIG. 2 is a flow chart showing an embodiment of the function of the comparison / determination means according to the present invention.

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

Now, it is assumed that the power plant is operating in parallel with the grid. The comparison / determination means 3 determines whether or not the rotation speed of the generator 20 detected by the speed detector 4 is equal to a predetermined value, and if they are not equal, a change in the rotation speed of the generator 20 and an action change amount detector 7 are used. The detected action change amount is compared, and when the change state is not the same, an alarm signal is output.

Further, the comparison / determination unit 3 determines that the rotation speed of the generator 20 detected by the speed detector 4 is equal to a predetermined value, or that the change in the rotation speed of the generator 20 and the change in the action change amount are the same. In the case, it is determined whether or not the speed setting mechanism is operating based on the speed setting position R ₀ detected by the speed setting position detector 5, and when it is operating, the speed setting position R ₀ and the action described above are determined. The change amount is compared, and an alarm signal is output if the change states are not the same.

Then, when the speed setting mechanism is not operating, or when the speed setting position R ₀ and the change in the action change amount are the same, the comparison / determination means 3 detects the load limit setting position detector 6. Based on the load limit setting position C ₀ is determined, it is determined whether the load limiting mechanism is operating, when it is operating, the load limit setting position C ₀ is compared with the action change amount, An alarm signal is output when the change states are not the same. When the load limiting mechanism is not operating, the procedure returns to the beginning and the above procedure is repeated.

FIG. 3 is a graph showing the system frequency (or the rotation speed of the generator 20) and the movement of the servo motor.

In the section indicated by reference numeral 31, the mechanically movable part of the servo motor 12 also operates in the closing direction as the system frequency (or the rotation speed of the generator 20) increases, and it can be determined that the section is normal.

In the section indicated by reference numeral 32, hunting occurs even though the system frequency (or the rotation speed of the generator 20) is stable, and it can be determined that there is an abnormality.

In the section indicated by reference numeral 33, the mechanically movable part of the servomotor 12 does not move, although the system frequency (or the rotation speed of the generator 20) has changed. This can be judged to be an abnormality in the mechanical lock, piping, or electric part.

〔The invention's effect〕

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 final stage of the speed governor are monitored. By comparing the change state of the action change amount of the mechanical movable part, it is possible to detect the failure of the governor during parallel operation with the power system of the power plant, and therefore, the conservative aspect. Not only that, it can contribute to the stabilization of the entire power generation system.

[Brief description of drawings]

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 flow chart showing an embodiment of the function of the comparison / determination means according to the present invention. FIG. 3 is a graph showing the system frequency and the movement of the servo motor. 3 ... Comparison determination 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 circuit breaker.

Claims (1)

[Claims] 1. A generator, a prime mover for driving the generator, a speed setter provided in the prime mover for setting a rotation speed of the generator, and a load limit setter for limiting an output of the prime mover. In a power plant with a governor, a parallel operation detector that detects whether this power plant is performing parallel operation with the power system, and a speed detector that detects the rotation 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 that detects the load limit setting position of the load limit setting device, and an action change amount detector that detects the action change amount of the mechanical movable part at the final stage of the speed governor,
Under the circumstance that the parallel determination operation is performed between the power generation plant and the electric power system detected by the parallel operation detection detector, the comparison determination means includes: Fault diagnosing device for speed governors, which has the functions up to. a) Based on the rotation speed of the generator detected by the speed detector and the operation change amount of the mechanical movable part at the final stage of the speed governor detected by the operation change amount detector, The state of change is compared, and if the state of change is not the same, an alarm signal is output. b) The speed setting position of the speed setting device detected by the speed setting position detector, and the action change amount of the mechanically movable part at the final stage of the speed governor detected by the action change amount detector. Based on the above, the states of these changes are compared, and if the states of the change are not the same, an alarm signal is output. c) The load limit setting position of the load limit setting device detected by the load limit setting position detector, and the action of the mechanical movable part at the final stage of the speed governor detected by the action change amount detector. Based on the amount of change, the states of these changes are compared, and if the states of change are not the same, an alarm signal is output.