JP2017066983A - Turbine control device, turbine, and method for reducing vibration value of turbine shaft - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a turbine from increased in speed without removing flexure of a turbine shaft.SOLUTION: A turbine remote controller determines before performing a normal operation after starting of a steam turbine whether or not a turbine vibration value exceeds a starting operation alarm value smaller than a normal operation alarm value set when a steam turbine is normally operated, and when the remote controller determines that the turbine vibration value exceeds a second set value, the remote controller informs of occurrence of an abnormal state. The turbine remote controller does not cause any motion of a ship body when the turbine vibration value exceeds the starting operation alarm, but executes a vibration value reducing operation for operating the steam turbine at the rotation speed where flexure of the turbine shaft can be removed.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a turbine control device, a turbine, and a turbine shaft vibration value reduction method.

A ship using a steam turbine as a ship engine (main engine) is a so-called auto-spin mode that functions in a state where the operation of the engine is ready to start (turning off, preparation for introducing steam into the steam turbine, etc.) AUTO SPIN MODE).
The auto-spin mode is a function that prevents the turbine shaft from being stopped by rotating the main shaft at a low speed by automatically opening and closing the forward governor and the reverse governor alternately by the turbine remote controller (Patent Documents 1 and 2). In addition, since the autospin mode is a function for the purpose of preventing the turbine shaft from stopping, the main shaft rotates (spins) at a low rotational speed (for example, 1-2 rpm).

As described above, the auto spin mode is set to automatically start when the engine operation start condition is satisfied and the spindle is stopped. The stop of the main spindle means that, for example, the rotation speed of the main spindle is equal to or less than a predetermined rotation speed (for example, 0.1 rpm, hereinafter referred to as “main shaft stop rotation speed”), and a predetermined time has elapsed since the main shaft stop rotation speed is reached. (For example, 20 seconds, hereinafter referred to as “main shaft stop confirmation time”) Later.
In the auto-spin mode, after the spindle stop confirmation time has elapsed, a small amount of the forward governor is opened to introduce steam into the forward steam turbine to increase the spindle speed. Close forward governor if exceeded.
Even if the forward governor is closed, the inertial force is applied to the main shaft, so the rotational speed of the main shaft drops over a certain period of time. After that, when the main shaft rotation speed again falls below the main shaft stop rotation speed and the main shaft stop confirmation time has passed, this time, by opening a small amount of the reverse governor, steam is introduced into the reverse steam turbine to rotate the main shaft. Increase the number. Then, when the rotational speed of the main shaft exceeds the main shaft stop rotational speed, the reverse governor is closed and the forward governor is opened again automatically.

  Such auto-spin mode is often performed during standby after ship berthing, etc., and a large amount of steam input to the steam turbine causes over-rotation of the turbine shaft or hull movement. Minimize the amount of steam input to the turbine.

Japanese Patent No. 4446992 JP 58-25843 A

As described above, since only a very small amount of steam is supplied to the steam turbine in the auto spin mode, if the auto spin mode is performed for a long time, it may act as a cooling effect on the steam turbine that has been warmed up. is there.
Further, since the main shaft in the auto spin mode repeats the slow rotation at a low rotational speed as described above, the rotational speed is insufficient to remove the initial bending (self-weight deflection) of the turbine shaft. In some cases, the speed of the steam turbine is increased without removing the deflection of the turbine shaft. As a result, since the speed of the steam turbine is increased without removing the deflection of the turbine shaft, the vibration of the turbine shaft is amplified and dissipated, which may lead to contact with a stationary portion (such as a labyrinth fin) of the steam turbine. .

When maintaining the standby state while keeping warm with respect to the turbine, it is necessary to input a higher amount of heat into the turbine and continuously rotate the turbine shaft at a relatively high rotational speed. For this reason, when the operator manually opens and closes the forward governor and the reverse governor, the hand spin is performed to rotate the spindle forward and backward at a higher rotational speed than in the auto spin mode.
By continuing this hand spin, heat diffusion by convection is promoted, and the turbine shaft and the interior of the vehicle interior are made thermally uniform. Further, due to the gyro effect in which the eccentricity of the rotor shaft approaches the center point on the same axis as the rotation increases, the turbine shaft unbalance is eliminated and the deflection of the turbine shaft is eliminated.
As described above, if the hand spin can be continued for a relatively long time, the heat nonuniformity and the deflection of the turbine shaft can be eliminated. However, in the case of thermal nonuniformity, the turbine shaft itself may bend due to this temperature nonuniform distribution. There may be a case where the hand spin cannot be performed for such a long time that the deflection of the turbine shaft can be eliminated due to an emergency discrete request by a port instruction at the time of departure from the ship.

If the deflection of the turbine shaft is not eliminated, vibration may occur in the steam turbine. Here, some steam turbines are provided with a vibration sensor, and when the vibration of the steam turbine exceeds a predetermined set value, an alarm is issued and the driver is alerted. Further, when the vibration of the steam turbine rises, some have a trip function for stopping the steam turbine.
However, since the auto spin mode described above is a function that alternately opens and closes the forward governor and the reverse governor in order to rotate the main shaft at a slow speed, conventionally, it is not operated while monitoring the vibration of the steam turbine. Absent.
In general, an alarm for steam turbine vibration is set corresponding to a vibration value of normal operation of the steam turbine (design value, for example, 10 to 20 μm). However, since the vibration when the rotation speed of the steam turbine is low (for example, vibration during hand spin) is relatively small, the alarm set value corresponding to the normal operation is too high for the low rotation speed. . For this reason, even if the vibration of the steam turbine exceeds the normal vibration value at low rotation after the start of the steam turbine, the operator does not judge it as abnormal if it is below the normal operation alarm value, and increases as it is. May be faster. As a result, the speed of the steam turbine is increased without removing the deflection or the like of the turbine shaft, so that the vibration of the turbine shaft is further amplified and dissipated, which may cause an alarm or a trip.

  As described above, if the speed of the turbine is increased without removing the deflection of the turbine shaft, vibrations of the turbine shaft may be further amplified and radiated, which is not preferable for the turbine.

  The present invention has been made in view of such circumstances, and the turbine controller, turbine, and vibration value of the turbine shaft that can prevent the turbine from being accelerated without the deflection of the turbine shaft being removed. An object is to provide a reduction method.

  In order to solve the above problems, the turbine control device, the turbine, and the turbine shaft vibration value reduction method of the present invention employ the following means.

  In the turbine control device according to the first aspect of the present invention, the vibration value of the steam turbine is set when the steam turbine is normally operated before the normal operation is performed after the start of the steam turbine used as a marine engine. A determination unit that determines whether or not a second setting value that is smaller than the set first set value is exceeded, and the determination unit determines that the vibration value exceeds the second setting value. And an informing means for informing the occurrence of.

  The turbine control device according to the present configuration controls a steam turbine used as a marine engine.

  In general, an alarm for vibration of the steam turbine due to the deflection of the turbine shaft or the like is set corresponding to the vibration value of the normal operation of the steam turbine. However, since the vibration when the rotation speed of the steam turbine is low is relatively small, the alarm set value corresponding to the normal operation is too high for the low rotation speed. For this reason, even if the vibration of the steam turbine exceeds the normal vibration value at low rotation after the start of the steam turbine, the operator does not judge it as abnormal if it is below the normal operation alarm value, and increases as it is. May be faster. As a result, vibration is more divergent, which can lead to alarms and trips.

Therefore, according to this configuration, the second set value that is smaller than the first set value that is set when the steam turbine is normally operated is set, and after the steam turbine is started, before the normal operation is performed, the steam turbine is set. It is determined by the determination means whether or not the vibration value exceeds the second set value. Then, when the determination unit determines that the vibration value of the steam turbine exceeds the second set value, the notification unit notifies the occurrence of the abnormality.
Thus, according to this configuration, when the steam turbine is operating at a low rotational speed after the steam turbine is started, the steam turbine can be set to a lower setting value for notifying the abnormality than in the normal operation. Therefore, the operator can recognize the abnormality. When the operator recognizes at an early stage that the vibration abnormality, that is, the turbine shaft is bent, etc., it becomes possible to eliminate the vibration before the vibration of the turbine shaft is further amplified and diverges.

  Therefore, this configuration can prevent the turbine from being accelerated without removing the deflection of the turbine shaft.

  In the first aspect, when the vibration value exceeds the second set value, a vibration value reduction operation is performed in which the steam turbine is operated at a rotation speed that does not cause a hull movement and can remove distortion of the turbine shaft. Control means may be provided.

  According to this configuration, vibration generated in the steam turbine can be reduced before the steam turbine is normally operated.

  In the first aspect, the steam turbine is operated so that the vibration value reduction operation alternately repeats the rotation of the main shaft of the ship on the forward side and the reverse side until the vibration value becomes equal to or less than the second set value. May be.

  According to this configuration, vibration generated in the steam turbine can be reduced more reliably.

  In the first aspect, the vibration value reduction operation may operate the steam turbine at a rotation speed that allows the steam turbine to be kept warm and does not cause hull movement.

  According to this configuration, vibration generated in the steam turbine can be more reliably reduced, and the steam turbine can be prevented from being cooled while the vibration value reduction operation is performed.

  In the first aspect, the vibration value reduction operation is lower than a rotational speed by a manual operation that is repeatedly performed with a slow forward and a slow reverse by a telegraph operation in order to prepare for an increase in speed of the steam turbine, and the turbine shaft In order to prevent this stop, the steam turbine may be operated at a higher rotational speed than the rotational speed in the automatic operation in which the slow speed forward and the slow speed reverse are repeated.

  According to this configuration, vibration generated in the steam turbine can be more reliably reduced, and the steam turbine can be prevented from being cooled while the vibration value reduction operation is performed.

  In the first aspect, the control unit may have a setting that allows the steam turbine to be accelerated without performing the vibration value reduction operation even if the vibration value exceeds the second set value. Good.

  According to this structure, even if the vibration value of a steam turbine is higher than usual, priority can be given to the normal operation of a steam turbine.

  The turbine control device according to the second aspect of the present invention is a turbine control device that controls a turbine, and before the normal operation is performed after the turbine is started, the vibration value of the turbine causes the turbine to perform a normal operation. A determination unit that determines whether or not a second setting value that is smaller than the first setting value that is set in this case is exceeded, and the determination unit that determines that the vibration value exceeds the second setting value And an informing means for informing the occurrence of an abnormality.

  A turbine according to a third aspect of the present invention includes the turbine control device described above.

  In the turbine shaft vibration value reducing method according to the fourth aspect of the present invention, before the steam turbine used as a marine engine is started and before normal operation is performed, the vibration value of the steam turbine performs normal operation of the steam turbine. A first step for determining whether or not a second set value smaller than the first set value set in the case of the first set value is exceeded, and the first step determines that the vibration value exceeds the second set value And a second step of notifying the occurrence of an abnormality.

  In the turbine shaft vibration value reducing method according to the fifth aspect of the present invention, the turbine vibration value is set when the turbine is normally operated before the normal operation is performed after the turbine is started. A first step for determining whether or not a second set value that is smaller than a set value is exceeded, and when the vibration value is determined to exceed the second set value by the first step, the occurrence of an abnormality is notified. And a second step.

  According to the present invention, there is an excellent effect that the speed of the turbine can be prevented from being increased without removing the deflection of the turbine shaft and the like.

It is a mimetic diagram explaining a schematic structure of a steam turbine concerning an embodiment of the present invention. It is a block diagram which shows the electrical structure which concerns on the abnormal vibration response | compatibility part with which the turbine remote control which concerns on embodiment of this invention is provided. It is the block diagram which showed schematic structure of the normal range calculation part which concerns on embodiment of this invention. It is the flowchart which showed the flow of the process from the engine stop which concerns on embodiment of this invention to starting preparations and acceleration. It is the block diagram which showed the operating condition of the vibration value reduction driving | operation which concerns on embodiment of this invention. It is the flowchart which showed the flow of the process of the vibration value reduction driving | operation which concerns on embodiment of this invention. It is the figure which showed the time change of the rotation speed of the main axis | shaft in the vibration value reduction operation | movement which concerns on embodiment of this invention.

  Hereinafter, an embodiment of a turbine control device, a turbine, and a turbine shaft vibration value reducing method according to the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic diagram illustrating a schematic configuration of a steam turbine 1 according to the present embodiment.

  The steam turbine 1 according to the present embodiment is used as a marine engine (main engine) as an example, and is a reheat turbine including a reheater 4R that heats steam discharged from a high-pressure turbine 2H. .

  As shown in FIG. 1, the steam turbine 1 includes a high-pressure turbine 2H, an intermediate-pressure turbine 2M, a rotary shaft 2HM, a main boiler 4H, and a reheater (boiler) 4R.

The high-pressure turbine 2H generates rotational driving force by being supplied with superheated steam from the main boiler 4H.
The intermediate pressure turbine 2M generates a rotational driving force when reheated steam is supplied from the reheater 4R.
The high-pressure turbine 2H and the intermediate-pressure turbine 2M are connected by the connecting shaft 3A and rotate the rotating shaft 2HM. The rotating shaft 2HM transmits the rotational driving force that is the output of the high-pressure turbine 2H and the intermediate-pressure turbine 2M to the propeller 23 via the reduction gear 21 and the main shaft 22.
The main shaft 22 is provided with a shaft generator 8. The shaft generator 8 generates power using at least a part of the rotational driving force supplied from the main shaft 22 to the propeller 23.

The main boiler 4H generates steam using heat obtained by burning fuel supplied from the outside, and supplies the steam to the high-pressure turbine 2H.
The reheater 4R reheats the steam discharged from the high pressure turbine 2H using the heat obtained by burning the fuel to obtain reheat steam, and supplies the reheat steam to the intermediate pressure turbine 2M.

  Furthermore, the steam turbine 1 is provided with a low-pressure turbine 2L, a reverse turbine 2B, and a condenser 9.

The low pressure turbine 2L is supplied with steam exhausted from the intermediate pressure turbine 2M to generate a rotational driving force.
The reverse turbine 2B is supplied with superheated steam from the main boiler 4H and generates a rotational driving force when the marine vessel is moved backward.
The low pressure turbine 2L and the reverse turbine 2B are connected by the connection shaft 3B and rotate the rotation shaft 2LB. The rotating shaft 2LB transmits the rotational driving force, which is the output of the low pressure turbine 2L and the reverse turbine 2B, to the propeller 23 via the reduction gear 21 and the main shaft 22.

  The condenser 9 returns steam discharged from the low-pressure turbine 2L and the reverse turbine 2B to water.

A forward governor 5H and a reverse governor 5B are provided in the supply path 6 for supplying steam from the main boiler 4H to the high-pressure turbine 2H and the reverse turbine 2B.
The forward governor 5H controls the flow rate of steam supplied from the main boiler 4H to the high-pressure turbine 2H according to the load of the steam turbine 1. On the other hand, the reverse governor 5B controls the flow rate of the steam supplied from the main boiler 4H to the reverse turbine 2B when the ship is moved backward. The opening degree of the forward governor 5H and the reverse governor 5B is controlled based on a governor opening instruction value output from a control device (hereinafter referred to as “turbine remote controller”) 7.

  In the following description, the rotation shafts 2HM and 2LB and the connection shafts 3A and 3B are collectively referred to as a turbine shaft (or turbine rotor). The vibration of the steam turbine 1 (turbine shaft) is referred to as turbine vibration, and the vibration value of the steam turbine 1 (turbine shaft) is referred to as turbine vibration value.

  FIG. 2 is a block diagram showing an electrical configuration of the abnormal vibration handling unit 30 provided in the turbine remote controller 7 according to the present embodiment. The abnormal vibration response unit 30 detects the presence or absence of an abnormality in turbine vibration, and performs notification and control of the steam turbine 1 according to the abnormality when there is an abnormality.

The abnormal vibration handling unit 30 includes a vibration alarm setting unit 32, a vibration determination unit 34, a notification unit 36, and a vibration value reduction control unit 38.
The turbine vibration value measured by the vibration sensor 40 is input to the turbine remote controller 7. The vibration sensor 40 is a non-contact sensor as an example, and measures the vibration (absolute peak difference) of the turbine shaft bearing by detecting the vibration amplitude of the turbine shaft as voltage vibration.

The vibration alarm setting unit 32 sets a normal operation alarm value, a normal operation trip value, and a start operation alarm value.
The normal operation of the steam turbine 1 is a state in which the steam turbine 1 can be accelerated (hereinafter referred to as “engine acceleration”). On the other hand, the start-up operation is a slow speed operation that is performed from when the steam turbine 1 is started until the normal operation is enabled, and when auto-spin, hand-spin, and try-engine are performed as described later. It is.

  The normal operation alarm value and the normal operation trip value are set values that are set to detect vibration abnormality of the steam turbine 1 (turbine shaft) when the steam turbine 1 is normally operated. Is predetermined based on the design value.

  The normal operation alarm value is a vibration value that requires abnormal notification because the vibration of the steam turbine 1 is abnormal, and is, for example, 75 μm. The normal operation trip value is a vibration value in which the vibration of the steam turbine 1 is abnormal and the steam turbine 1 needs to be stopped, and is, for example, 125 μm.

On the other hand, the start-up operation alarm value is a set value that is set to detect vibration abnormality of the steam turbine 1 (turbine shaft) when the steam turbine 1 is started-up.
The startup operation alarm value is a vibration value in which the vibration of the steam turbine 1 is abnormal and requires notification to the operator, and is a value smaller than the normal operation alarm value.

  The startup operation alarm value is calculated by a normal range calculation unit 42 provided in the turbine remote controller 7.

FIG. 3 is a block diagram showing a schematic configuration of the normal range calculation unit 42.
The normal range calculation unit 42 includes a storage unit 44, a measurement data collection unit 46, a data sorting unit 48, and a normal range setting unit 50.

  The storage unit 44 stores a plurality of monitoring items for the steam turbine 1 to be diagnosed as a main monitoring item and a sub monitoring item whose behavior changes according to the state of the main monitoring item. . In the present embodiment, spindle speed, engine output, bearing temperature, turbine vibration, turbine shaft position, steam temperature, and pressure are registered as monitoring items, and spindle speed and engine output are registered as main monitoring items. As subordinate monitoring items, bearing temperature, vibration, steam temperature, and pressure are registered.

  Measurement data is transmitted to the measurement data collection unit 46 in real time from sensors attached to each part of the steam turbine 1. As a result, the measurement data collection unit 46 sequentially accumulates measurement data for each monitoring item, that is, measurement data for the main shaft rotation speed, engine output, bearing temperature, turbine vibration, turbine shaft position, steam temperature, and pressure.

  The data sorting unit 48 refers to the information about the main monitoring item and the sub monitoring item stored in the storage unit 44, and uses the measurement data of each sub monitoring item stored in the measurement data collecting unit 46 as the measurement data. Is classified according to the state of the main monitoring item when the is acquired. For example, when the spindle speed is assumed as the main monitoring item, the range of the spindle speed in the normal state, for example, the range from the minimum speed (0 rpm) to the maximum speed is divided at predetermined speed increments. Based on the measurement data of the sub-monitoring item based on.

  The normal range setting unit 50 sets the normal range of the sub-monitoring item for each section using the measurement data of the sub-monitoring item in each section. Specifically, the normal range setting unit 50 sets a normal range from the average value and standard deviation of measurement data in each section. For example, the normal range setting unit 50 has a coefficient α corresponding to each slave monitoring item, and a value obtained by subtracting a value obtained by multiplying the coefficient α by the standard deviation σ from the average value μ is set as a lower limit value of the normal range. A value obtained by multiplying the coefficient α by the standard deviation σ and the average value μ is set as the upper limit value of the normal range.

The normal range is expressed as follows.
Lower limit: μ-α * σ
Upper limit: μ + α * σ
Here, the average value μ and the standard deviation σ are expressed by the following equations (1) and (2), respectively.

In the above expressions (1) and (2), T _k (k = 1, 2,..., N) is measurement data in a certain section, and n is the number of measurement data in a certain section.

  Further, the normal range setting unit 50 updates the normal range at a predetermined time interval using the measurement data in the past predetermined period from the present collected by the measurement data collecting unit 46. As a result, the normal range is updated from time to time in a form that always incorporates new measurement data.

  As described above, the normal range calculation unit 42 according to the present embodiment accumulates the vibration data measured by the vibration sensor 40 by the measurement data collection unit 46, and the accumulated vibration data is stored in the steam partition 1 by the data partition unit 48. Sort by number of rotations. Then, the normal range of the vibration data divided in the range of the minute rotation speed (for example, 0 to 5 rpm in the spindle rotation speed) is calculated by the normal range setting unit 50. This calculated range is set as the startup operation alarm value. The startup operation alarm value may be a value obtained by adding a predetermined margin to the calculated value, instead of using the value calculated by the normal range setting unit 50 as it is.

The vibration determination unit 34 compares the current turbine vibration value measured by the vibration sensor 40 with the normal operation alarm value, the normal operation trip value, and the start operation alarm value.
When the steam turbine 1 is performing normal operation, the vibration determination unit 34 determines whether the measured turbine vibration value exceeds a normal operation alarm value or a normal operation trip value.

  When the turbine vibration value exceeds the normal operation alarm value, the notification unit 36 notifies the operator of an alarm indicating that the turbine vibration value is abnormal by sound or image. When the alarm is notified, the operator manually performs an operation for stopping the steam turbine 1. Further, when the turbine vibration value exceeds the normal operation trip value, the turbine remote controller 7 forcibly stops the steam turbine 1.

  In addition, the vibration determination unit 34 according to the present embodiment determines whether or not the turbine vibration value exceeds the startup operation alarm value before performing normal operation after startup of the steam turbine 1.

  When the turbine vibration value exceeds the startup operation alarm value, the notification unit 36 notifies the operator that the turbine vibration value is abnormal by voice or image.

Here, as a factor that the turbine vibration value exceeds the normal vibration value, there is temperature nonuniformity of the casing and the turbine shaft in addition to the deflection of the turbine shaft.
The abnormality of the turbine vibration value due to the temperature nonuniformity of the passenger compartment and the turbine shaft will be described below.

The non-uniform temperature of the passenger compartment refers to non-uniform heat in the upper and lower parts of the passenger compartment and non-uniform heat in the turbine axial direction, which causes unequal deformation of the passenger compartment. When the unequal deformation of the passenger compartment increases, contact vibration between the turbine shaft and the passenger compartment is caused. Further, the temperature unevenness of the turbine shaft is caused by the fact that the upper portion of the casing maintains a high temperature while the turbine shaft is stopped, while the lower portion of the casing has a lower temperature than the upper portion of the casing. There is a case where a temperature difference occurs between the upper and lower sides of the turbine shaft, and the turbine shaft itself may be bent due to this temperature non-uniform distribution.
If the turbine shaft continues to rotate, such temperature non-uniformity does not occur in the turbine shaft itself, so turning and auto-spin are performed for the purpose of preventing such temperature non-uniformity of the turbine shaft. However, since the amount of heat input to the steam turbine 1 is small in auto-spin, the vehicle compartment cannot be kept warm.
When the turbine shaft is cooled by auto-spin, etc., when the warm air is not sufficient, the atmospheric temperature in the passenger compartment becomes non-uniform, which may cause unequal deformation. This causes a shift in the positional relationship between the casing, turbine bearing, turbine shaft, etc., which affects the vibration characteristics of the turbine shaft or leads to contact (and hence vibration) between the turbine shaft and the stationary part of the passenger compartment. In some cases, the vibration value exceeds the normal range.

When the turbine vibration value exceeds the startup operation alarm value, the vibration value reduction control unit 38 performs the vibration value reduction operation.
In the vibration value reduction operation, the steam turbine 1 is operated at a rotational speed that does not cause the hull movement and can remove the distortion of the turbine shaft. The vibration value reduction operation is not performed manually like the hand spin, but automatically repeats the slow forward and slow reverse like the auto spin mode, in other words, the vibration value reduced auto spin mode. It should be said. By this vibration value reduction operation, the vibration of the steam turbine 1 can be reduced before the steam turbine 1 is normally operated. The target rotational speed of the vibration value reduction operation is lower than the rotational speed in Try-Engine and higher than the rotational speed in the auto spin mode, as will be described later in detail.

  Here, generally, the alarm for the vibration value of the steam turbine is set in correspondence with the vibration of the normal operation of the steam turbine. However, since the vibration when the rotation speed of the steam turbine is low is relatively small, the alarm set value corresponding to the normal operation is too high for the low rotation speed. For this reason, even after the steam turbine 1 is started, even if the turbine vibration exceeds the normal vibration value at the low rotation, the driver does not determine that there is an abnormality if it is below the normal operation alarm value, and the speed is increased as it is. There is a case to let you. As a result, the turbine vibration is more divergent, and there is a possibility of alarming or tripping.

Therefore, according to the present embodiment, as described above, a startup operation alarm value that is smaller than the normal operation alarm value that is set when the steam turbine 1 is normally operated is set.
The vibration determination unit 34 determines whether or not the vibration value of the steam turbine 1 exceeds the start operation alarm value before the normal operation is performed after the start of the steam turbine 1. Then, when the vibration determination unit 34 determines that the turbine vibration value exceeds the startup operation alarm value, the notification unit 36 notifies the occurrence of an abnormality.
Thus, according to the present embodiment, when the steam turbine 1 is operated at a low speed after the steam turbine 1 is started, the start-up operation alarm value for notifying abnormality is set lower than that in the normal operation. Thus, the vibration abnormality of the steam turbine 1 can be determined early, and the operator can recognize the abnormality. Therefore, the turbine remote controller 7 according to the present embodiment can more reliably detect abnormal vibration of the steam turbine 1 when the steam turbine 1 is started. As described above, when the operator recognizes at an early stage that the vibration abnormality, that is, the occurrence of the deflection of the turbine shaft or the like, these can be resolved before the vibration of the turbine shaft is further amplified and diverges.

  The turbine remote controller 7 can reduce the vibration generated in the steam turbine 1 by performing the vibration value reduction operation when the turbine vibration value exceeds the start operation alarm value.

  FIG. 4 is a flowchart showing a flow of processing from the stop of the steam turbine 1 as an engine (hereinafter referred to as “engine stop”) to the start preparation of the steam turbine 1 and the engine speed increase. The processing according to steps 108 to 118 in FIG. 4 is executed by the abnormal vibration handling unit 30.

  First, step 100 is a state in which the steam turbine 1 as an engine is stopped.

  The next step 102 is a state where the preparation for starting the steam turbine 1 is completed.

  In the next step 104, manual spin is performed to rotate the main shaft 22 forward and backward by repeating the opening and closing operation of the forward governor 5H and the reverse governor 5B in a short time. Note that the auto spin mode may be performed between step 102 and step 104.

  In the next step 106, when the operator determines that the steam turbine 1 is stable by hand spin, confirmation of the steam turbine 1 by a telegraph operation, so-called Try-Engine is performed. In the Try-Engine according to the present embodiment, a steam turbine is instructed by a telegraph by repeating slow forward and slow reverse at a predetermined rotational speed (for example, the main shaft rotational speed is 20 to 25 rpm) while monitoring turbine vibration. Confirm that 1 is driven, and prepare for engine speedup. In Try-Engine, the spindle speed is low and the forward and reverse are repeated in a short time, so the hull does not move. Also, try-engine repeats forward and backward in the same way as hand spin, but the time for maintaining forward and reverse travel is longer for try-engine than for hand spin.

  In the next step 108, it is determined by the vibration determination unit 34 whether or not the turbine vibration value measured by the vibration sensor 40 is equal to or less than the startup operation alarm value. In this case, the process proceeds to step 110.

  In step 110, since the turbine vibration value exceeds the startup operation alarm value, the notification unit 36 reports an abnormality in the turbine vibration value.

In the next step 112, it is determined whether or not the vibration value reduction control unit 38 is set to be bypassed. If the determination is affirmative, the process proceeds to step 120. If the determination is negative, the process proceeds to step 114.
The bypass setting is a setting that allows the steam turbine 1 to be accelerated without executing the vibration value reduction operation even when the turbine vibration value exceeds the startup operation alarm value. The bypass setting is provided for giving priority to engine speedup even when the turbine vibration value is higher than usual, for example, when a sudden shore separation is required. On or off is selected.

  In step 114, the vibration value reduction control unit 38 starts the vibration value reduction operation. When the vibration value reduction operation is started, the telegraph operation is disabled.

  In step 116, it is determined whether or not the turbine vibration value is equal to or less than the startup operation alarm value. If the determination is affirmative, the process proceeds to step 118. If the determination is negative, the vibration value reduction operation is continued.

  In step 118, the vibration value reduction control unit 38 finishes the vibration value reduction operation, returns to step 106, and continues Try-Engine.

In step 120, which is shifted to the case where an affirmative determination is made in step 108, it is determined whether or not the speed increase preparation is completed. If the determination is affirmative, the process proceeds to step 122. If the determination is negative, the process returns to step 106.
In addition, as an example, the determination as to whether or not the speed increase preparation has been completed is performed by a sub-telegraph that indicates the state of the steam turbine 1.

  In the next step 122, since preparation for starting is completed, normal engine speed increase by telegraph is performed.

  As shown in the flowchart of FIG. 4, the Try-Engine performed in Step 106 is prepared for engine acceleration by repeating the slow forward and the reverse by the operator's telegraph operation while monitoring the turbine vibration. Is to prepare. Conventionally, if the turbine vibration value in the case of performing this Try-Engine is equal to or less than the normal operation alarm value, even if it exceeds the vibration value at the time of normal slow forward or slow reverse (engine preparation), There is a possibility that the driver may perform speed-up operation (normal operation) without concern.

In general, when the turbine shaft is excessively bent due to its own weight or the like, the turbine vibration value mainly includes an integral multiple component (sometimes 1N component) of the rotational speed due to rotor unbalance in the process from startup to speed increase. The increase and the divergence tendency are shown.
For this reason, as described above, even if the turbine vibration value is small at the time of start-up, if the speed is increased in a state exceeding the normal vibration value at the time of start-up, the turbine vibration will increase and diverge. 1 trip and possibly turbine damage. On the other hand, if the turbine vibration value at the time of startup does not exceed the normal vibration value, the subsequent engine speed increase can be performed stably without the turbine vibration being diverged.

Therefore, in the present embodiment, when the steam turbine 1 is operated at a rotation speed at which the hull movement does not occur by manual operation (in this embodiment, as an example, when Try-Engine is performed), the turbine vibration value is When the normal vibration value (start-up operation alarm value) is exceeded, a message to that effect is issued to the operator and a vibration value reduction operation is performed. On the other hand, when the bypass setting ON is selected, even if the turbine vibration value exceeds a normal value, the engine speed can be increased without performing the vibration value reduction operation.
In the vibration value reduction operation, the target rotational speed of the turbine shaft (for example, 10 rpm, which is about the same as the hand spin) is set in advance, and the forward and backward spins are automatically repeated while monitoring the turbine vibration value. Then, the vibration value reduction operation is repeated until the turbine vibration value becomes equal to or lower than the start operation alarm value. When the turbine vibration value becomes equal to or lower than the start operation alarm value, Try-Engine is continued again.

FIG. 5 is a block diagram showing the operating conditions of the vibration value reduction operation.
When the vibration value reduction operation is possible, as shown in FIG. 5, the vibration value reduction operation is selected (condition A), and the vibration value reduction operation and the auto spin mode are not set to bypass (condition B). The control mode is the lever (condition C), the telegraph is set to the stop position (condition D), and the spindle rotational speed N is equal to or lower than the predetermined rotational speed N0 and N0 or lower has elapsed for a predetermined time (condition E). ), The turning gear is not engaged (Condition F), the steam turbine 1 is not in an emergency stop state (Condition G), and the turbine vibration value in Try-Engine exceeds the start operation alarm value (Condition) This is a case where all of H) are satisfied.

Next, details of the vibration value reduction operation according to the present embodiment will be described with reference to FIGS.
FIG. 6 is a flowchart showing a flow of processing of the vibration value reduction operation.
FIG. 7 is a diagram showing temporal changes of the spindle rotational speed and the forward governor 5H and the reverse governor 5B in the vibration value reduction operation.

  6 and 7, in the vibration value reduction operation, the main shaft rotation of the ship is alternately repeated on the forward side and the reverse side until the turbine vibration value becomes equal to or lower than the startup operation alarm value. As a result, the main shaft 22 is alternately rotated at a relatively high rotational speed, so that vibration generated in the steam turbine 1 (turbine shaft) can be more reliably reduced.

  In FIG. 7, the horizontal axis represents time, and the vertical axis represents the spindle rotational speed during forward (AHD) or reverse (AST) and the opening degree of the forward governor 5H and reverse governor 5B. The one-dot chain line in FIG. 7 shows the time change of the main shaft rotation speed, and the solid line shows the time change of the opening degree of the forward governor 5H and the opening degree of the reverse governor 5B.

N0 is the spindle speed (for example, 1 rpm) that enables the vibration value reduction operation to be started.
N1 is a target value (for example, 10 rpm, hereinafter referred to as “target rotational speed”) of the spindle rotational speed in the vibration value reduction operation. The target rotation speed is lower than the rotation speed in Try-Engine and higher than the rotation speed in the auto spin mode. That is, the target rotation speed is approximately the same as the rotation speed in hand spin by manual operation.
N2 is a rotation speed (for example, 15 rpm, hereinafter referred to as “alarm notification rotation speed”) in which an alarm is notified when the spindle 22 over-rotates in the vibration value reduction operation.
N3 is a main shaft rotation speed (for example, 20 rpm, hereinafter referred to as “trip rotation speed”) at which the main shaft 22 overrotates and the steam turbine 1 is tripped in the vibration value reduction operation.

Even if the main shaft rotation speed becomes the target rotation speed and the alarm notification rotation speed, the hull does not move, but when the main shaft rotation speed reaches the trip rotation speed, the hull starts to move.
Further, the opening degrees A1 and A2 of the forward governor 5H and the opening degree B1 of the reverse governor 5B are determined in advance so that the spindle rotational speed does not reach the alarm notification rotational speed and the trip rotational speed. Further, the opening degrees A1 and A2 of the forward governor 5H and the opening degree B1 of the reverse governor 5B are, for example, the opening degrees at which the steam amount capable of maintaining the warm air of the steam turbine 1 can be input to the steam turbine 1.

  When the vibration value reduction operation is started, first, the forward governor 5H and the reverse governor 5B are closed in step 200.

  In the next step 202, it is determined whether or not the spindle speed N is N <N0 and a predetermined time (period t1 in FIG. 7 and hereinafter referred to as “N0 arrival confirmation time”) has elapsed. In this case, the routine proceeds to step 204, and the vibration value reduction operation is started.

  In step 204, the forward governor 5H is opened at an opening A1, and the opening A1 is maintained for a holding time t2 (for example, 20 sec).

  In the next step 206, it is determined whether or not the spindle rotational speed N exceeds the target rotational speed N1 and is less than the alarm notification rotational speed N2 (N1 <N <N2). If the determination is affirmative, the process proceeds to step 208. . If the determination is negative (N <N1), the process returns to step 204, and the opening degree of the forward governor 5H is obtained by adding a predetermined opening degree α to the opening degree A1 that is the initial value (A1 = A1 + α). ).

  In step 208, the opening degree of the forward governor 5H is set to 0, and the forward governor 5H is closed.

  In the next step 210, it is determined whether or not the spindle rotational speed N has become less than the target rotational speed N1. If the determination is affirmative, the process proceeds to step 212. If the determination is negative, the forward governor 5H is kept closed. .

  In step 212, the reverse governor 5B is opened at the opening B1, and the opening B1 is maintained for a holding time t3 (for example, 40 sec).

  In the next step 214, it is determined whether or not the spindle rotational speed N exceeds the target rotational speed N1 and is less than the alarm notification rotational speed N2 (N1 <N <N2). If the determination is affirmative, the process proceeds to step 216. . In the case of a negative determination (N <N1), the process returns to step 212, and the opening degree of the reverse governor 5B is obtained by adding a predetermined opening degree β to the opening degree B1 that is the initial value (B1 = B1 + β ).

  In step 216, the opening degree of the reverse governor 5B is set to 0, and the reverse governor 5B is closed.

  In the next step 218, it is determined whether or not the spindle rotational speed N has become less than the target rotational speed N1. If the determination is affirmative, the process proceeds to step 220. If the determination is negative, the reverse governor 5B is kept closed. .

  In step 220, the forward governor 5H is opened at the opening A2, and the opening A2 is maintained for a holding time t4 (for example, 30 sec). The reason why the opening degree A2 of the forward governor 5H is larger than the previous opening degree A1 is that the opening degree of the forward governor 5H is made larger because the ship has a reverse foot before the opening degree A2. This is because there is a need to cancel this gait. The reverse travel means that the inertia on the reverse rotation side remains.

  In the next step 222, it is determined whether or not the spindle rotational speed N exceeds the target rotational speed N1 and is less than the alarm notification rotational speed N2 (N1 <N <N2). If the determination is affirmative, the process proceeds to step 224. . In the case of a negative determination (N <N1), the process returns to step 220, and the opening degree of the forward governor 5H is calculated by adding a predetermined opening degree α to the opening degree A2 that is the initial value (A2 = A2 + α ).

  In step 224, the opening degree of the forward governor 5H is set to 0, and the forward governor 5H is closed.

  In the next step 226, it is determined whether or not the spindle rotational speed N has become less than the target rotational speed N1. If the determination is affirmative, the process proceeds to step 228. If the determination is negative, the forward governor 5H is kept closed. .

  Step 228 determines whether or not the turbine vibration value is equal to or less than the startup operation alarm value. If the determination is affirmative, the process proceeds to step 230. If the determination is negative, the process proceeds to step 212, and the vibration value reduction operation is continued. To do.

  Step 230 ends the vibration value reduction operation, returns to Step 106 in FIG. 4, and continues Try-Engine.

  Steps 228 and 230 are the same as steps 116 and 118 in FIG.

Further, in the vibration value reduction operation, a steam amount capable of maintaining warm air is supplied to the steam turbine 1 to rotate the main shaft 22 of the ship. Thereby, the vibration generated in the steam turbine 1 can be more reliably reduced, and the steam turbine 1 can be prevented from being cooled while the vibration value reduction operation is being performed.
Below, the cooling prevention of the steam turbine 1 by execution of a vibration value reduction operation | movement is demonstrated in detail.

In the autospin that has been conventionally performed, since steam is input into the steam turbine 1 only in an extremely small amount and intermittently, the amount of heat input into the steam turbine 1 is small and warming is inhibited.
Here, intermittent refers to starting auto-spin, and (1) Forward governor open → (2) Spindle 22 rotation start → (3) Forward governor closed → (4) Spindle 22 rotational speed drop → (5) Spindle 22 rotation stop → (6) Spindle 22 rotation stop confirmation time (about 20 seconds) → (7) Reverse governor open ... Repeated operations such as (3) Forward governor closed (7) The reverse governor opening period is long, that is, the period during which steam is not charged is long. In the conventional auto-spin, when the forward governor is closed and the rotation of the main shaft 22 remains, the reverse governor is not shifted to open. For this reason, steam is not input into the steam turbine 1 during the period from (4) to (6).

On the other hand, in the vibration value reduction operation according to the present embodiment, compared with the conventional auto spin, (4) Decrease in the rotation speed of the main shaft 22 → The rotation speed of the main shaft 22 becomes equal to or less than the target rotation speed. Since the operation is performed without waiting for the rotation of the main shaft 22 to stop, such as when the governor is opened, the period in which the steam is not supplied to the steam turbine 1 is shortened as much as possible. Further, the vibration value reduction operation is performed by supplying a relatively large amount of steam to the steam turbine 1 until reaching a rotational speed higher than the rotational speed (for example, 1 to 2 revolutions / minute) of the main shaft 22 in auto-spin. Therefore, the steam is charged, and the amount of heat input to the steam turbine 1 increases.
For this reason, cooling of the steam turbine 1 can be prevented in the vibration value reduction operation according to the present embodiment.

As described above, the turbine remote controller 7 according to the present embodiment is configured so that the turbine vibration value is set when the steam turbine 1 is normally operated before the normal operation is performed after the steam turbine 1 is started. It is determined whether or not a startup operation alarm value smaller than the alarm value is exceeded, and when it is determined that the turbine vibration value exceeds the second set value, the occurrence of an abnormality is notified.
As described above, when the steam turbine 1 is operated at a low rotation speed after the start of the steam turbine 1, the vibration abnormality of the steam turbine 1 is caused by lowering the set value for reporting the abnormality than in the normal operation. The pilot can recognize the abnormality at an early stage.
Therefore, the turbine remote controller 7 according to the present embodiment can prevent the steam turbine 1 from being accelerated without removing the deflection of the turbine shaft and the like.

  As mentioned above, although this invention was demonstrated using the said embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. Various changes or improvements can be added to the above-described embodiment without departing from the gist of the invention, and embodiments to which the changes or improvements are added are also included in the technical scope of the present invention.

For example, in the above-described embodiment, the embodiment in which the present invention is applied to the marine steam turbine 1 has been described. However, the present invention is not limited to this, and the turbine is not limited to the marine use but for onshore power generation. It is good also as a form applied to not only the turbine of this, or the steam turbine 1, but a gas turbine.
In the case of this form, before the turbine control device performs normal operation after starting the turbine, the turbine set value is a second set value that is smaller than the first set value that is set when the turbine is operated normally. When it is determined that the turbine vibration value exceeds the second set value, the occurrence of a turbine shaft abnormality is notified. The normal operation is, for example, a state where a generator is connected to the turbine shaft and the turbine can be accelerated when the turbine is used for power generation, or a state where the turbine is operated at the rated rotational speed.

  The processing flow in FIGS. 4 and 6 described in the above embodiment is also an example, and unnecessary steps can be deleted, new steps can be added, and the processing order can be changed without departing from the scope of the present invention. It may be replaced.

1 Steam turbine 7 Turbine remote control (turbine control device)
34 Vibration determination unit (determination means)
36 Notification part (notification means)
38 Vibration value reduction control unit (control means)

Claims (10)

A second setting in which the vibration value of the steam turbine is smaller than the first setting value set when the steam turbine is normally operated before the normal operation is performed after the start of the steam turbine used as a marine engine. Determining means for determining whether or not the value is exceeded;
An informing means for informing the occurrence of an abnormality when the determining means determines that the vibration value exceeds the second set value;
A turbine control device comprising:   When the vibration value exceeds the second set value, control means is provided for performing vibration value reduction operation for operating the steam turbine at a rotation speed that does not cause hull movement and can remove distortion of the turbine shaft. Item 5. The turbine control device according to Item 1.   The said vibration value reduction driving | operation operates the said steam turbine so that rotation of the main axis | shaft of the ship may be repeated alternately on the forward side and the reverse side until the said vibration value becomes below the said 2nd setting value. Turbine control device.   4. The turbine control device according to claim 2, wherein in the vibration value reduction operation, the steam turbine is operated at a rotation speed capable of maintaining warm air of the steam turbine and causing no hull movement. 5.   The vibration value reduction operation is lower than the rotational speed by manual operation that is repeatedly performed with a slow speed forward and a slow speed reverse by a telegraph operation in order to prepare for the speed increase of the steam turbine, and in order to prevent the turbine shaft from stopping. The turbine control device according to claim 4, wherein the steam turbine is operated at a higher rotational speed than that in an automatic operation in which a slow forward and a slow reverse are repeatedly performed.   The turbine control device according to claim 2, wherein the control means has a setting that allows the steam turbine to be accelerated without performing the vibration value reduction operation even if the vibration value exceeds the second set value. A turbine control device for controlling a turbine,
Before starting normal operation after starting the turbine, it is determined whether or not the vibration value of the turbine exceeds a second set value that is smaller than the first set value that is set when the turbine is normally operated. Determination means to perform,
An informing means for informing the occurrence of an abnormality when the determining means determines that the vibration value exceeds the second set value;
A turbine control device comprising:   A turbine comprising the turbine control device according to claim 1 or 7. A second setting in which the vibration value of the steam turbine is smaller than the first setting value set when the steam turbine is normally operated before the normal operation is performed after the start of the steam turbine used as a marine engine. A first step of determining whether the value is exceeded;
A second step of notifying the occurrence of an abnormality when it is determined in the first step that the vibration value exceeds the second set value;
A method for reducing the vibration value of a turbine shaft. Before starting normal operation after starting the turbine, it is determined whether or not the vibration value of the turbine exceeds a second set value that is smaller than a first set value that is set when the turbine is normally operated. The first step;
A second step of notifying the occurrence of an abnormality when it is determined in the first step that the vibration value exceeds the second set value;
A method for reducing the vibration value of a turbine shaft.

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