JP3567296B2 - Turbine control unit - Google Patents

Description

[0001]
[Industrial applications]
The present invention relates to a turbine control device for a steam turbine having a turbine bypass system.
[0002]
[Prior art]
A steam turbine having a high-pressure turbine and an intermediate-pressure turbine driven by steam reheated after driving the high-pressure turbine, and having a turbine bypass system for bypassing both turbines, requires a system disclosed in As disclosed in Japanese Patent No. 65003, there is known a medium pressure starting method in which steam is first supplied to a medium pressure turbine and then steam is supplied to a high pressure turbine.
FIG. 2 shows a system diagram of a steam turbine system having a turbine bypass system. The main steam system 21 from the heater 18 of the boiler 1 to the high-pressure turbine 4 is provided with a main steam stop valve 2 and a control valve 3 for controlling a steam flow rate. , A reheat steam stop valve 7 and an intercept valve 8 and an intercept bypass valve 9 for controlling a steam flow rate are arranged. The condensed water collected in the condenser 12 after work is sent again to the heater 18 of the boiler 1 by a condensing system 25 provided with a pump device 19. A generator 13 is connected as a load to the high-pressure turbine 4, the intermediate-pressure turbine 10, and the low-pressure turbine 11. The check valve 5 is provided to prevent a backflow of steam from the turbine bypass system 23 to the high-pressure turbine 4.
The turbine bypass system means that the steam generated in the heater 18 of the boiler 1 is circulated to the reheater 6 and the condenser 12 of the boiler 1 without passing through the steam turbines 4, 10, and 11, and the startup time of the boiler 1 This is a bypass system for performing operations such as shortening of operation time and continuation of in-house independent operation.
The flow of steam during operation of the turbine bypass system will be described. The steam generated in the heater 18 of the boiler 1 flows into the turbine bypass system 23 from the main steam system 21, passes through the high-pressure bypass valve 14 of the turbine bypass system, bypasses the high-pressure turbine 4, and reheats the boiler 1. Flow into 6. The steam reheated through the reheater 6 passes through the low-pressure bypass valve 15 and flows into the condenser 12 from the steam system 24. Therefore, the intermediate pressure turbine 10 and the low pressure turbine 11 are also bypassed. In this way, the steam generated in the boiler 1 flows into the condenser 12 through the main steam system 21, the turbine bypass system 23, the reheating system 22, and the steam system 24, and bypasses the steam turbines 4, 10, and 11. I do.
Now, in such a conventional turbine system, during normal operation, the steam generated in the heater 18 of the boiler 1 passes through the control valve 3 of the main steam system 21, performs work in the high-pressure turbine 4, and then performs a check. After passing through the valve 5 and being reheated by the reheater 6, the intermediate pressure turbine 10 and the low pressure turbine 11 work via the intercept valve 8 and the intercept bypass valve 9 of the reheat system 22, and then the condenser 12 Is discharged.
On the other hand, at the time of turbine ventilation at the time of startup, steam is first introduced into the intermediate-pressure turbine 10 and the medium-pressure startup is performed. That is, the steam from the heater 18 of the boiler 1 passes through the main steam system 21, passes through the high-pressure bypass valve 14 of the high-pressure bypass system 23, is reheated by the reheater 6, and then intercepts by the reheat system 22. It is sent to the medium pressure turbine 10 and further to the low pressure turbine 11 via the valve 8 and the intercept bypass valve 9, and generally performs the operations from turbine ventilation to speed-up and even joining. The pressure of the reheated steam introduced into the intermediate pressure turbine 10 is controlled to a predetermined value by the low pressure bypass valve 15 having a large capacity. Here, the control valve 3 is in the fully closed state from the turbine ventilation to the admission, and steam is not introduced into the high-pressure turbine 4. If the load is to be further increased after the introduction, the steam control valve 3 is opened and steam is introduced into the high-pressure turbine 4.
When starting the steam turbine having the turbine bypass system, the steam turbine is first reset, the main steam stop valve 2 and the reheat steam stop valve 7 are fully opened, and the control valve is used to warm up the high-pressure turbine 4. 3 is set to a constant opening, the intercept bypass valve 9 is gradually opened, and steam flows into the steam turbine to increase the speed of the turbine. After the insertion, the intercept bypass valve 9 and the intercept valve 8 are opened. After the intercept valve 8 is fully opened, the control valve 3 is opened, and more steam flows into the intermediate pressure turbine. As the amount of steam flowing into the steam turbine increases, the high-pressure bypass valve 14 and the low-pressure bypass valve 15 close, and finally close completely, and a normal operation state is established.
FIG. 7 shows the opening / closing characteristics of the intercept valve 8 and the control valve 3. In FIG. 7, the valve opening command signal is from 0 to a in the speed control region, the intercept valve 8 is gradually opened, and after a, the load control region is opened, and the control valve 3 is opened.
[0003]
FIG. 6 shows an example of a conventional turbine control device. Normally, a rated turbine speed is set in the signal generator 600, a deviation from the turbine actual speed signal 620 is obtained by a subtractor 641, multiplied by a speed adjustment rate 602, and the position of the load setter 604 is determined. The addition is performed in the adder 642. At this time, since the position of the load limiter 603 is at the fully open position, the output signal of the adder 642 is selected by the low value selection circuit 607, and the opening / closing valve opening characteristic 608, the intercept valve opening characteristic 610, and A valve opening command is output to the control valve 3 and the intercept valve 8 through the control valve opening speed change rate limit 609 and the intercept valve opening speed change rate limit 611. Here, the valve opening command to the control valve 3 and the intercept valve 8 is a deviation signal between the actual valve opening of the control valve 3 and the actual valve opening of the intercept valve 8.
Now, when load interruption occurs, the balance between turbine inflow energy and output energy is lost, the turbine speed increases, and the intercept valve 8 and the control valve 3 are rapidly closed. Further, the load cutoff detection signal 621 (or the power load unbalance operation signal 622 or the like) is input to the set terminal of the flip-flop 605, and the governor run-back signal 651 is input to the load setting unit 604 by the load cutoff detection signal 621. Then, the position of the load setting device 604 is run back. The runback position is detected by the comparator 606, and the runback is stopped by resetting the runback start flip-flop 605 when the runback position is reached.
As described above, when load interruption occurs, the control valve 3 and the intercept valve 8 are rapidly closed, and the steam flowing into the turbine is rapidly reduced, so that the turbine speed is reduced. Due to this turbine speed drop, when the output of the subtractor 641 is equal to or lower than the turbine rated speed, a + signal is output and the intercept valve 8 is opened. Although this speed control is performed by the intercept valve 8, the amount of the turbine speed drop may exceed the intercept valve control region, the control valve 3 may also be opened, and speed fluctuations may occur due to mutual interference of the turbine speed control. FIG. 8 shows the characteristics of the turbine speed and the valve opening degree when the load is cut off. In FIG. 8, when the turbine speed decreases, the valve opening control signal becomes an open command, and the control valve 3 and the intercept valve 8 open to increase the turbine speed. On the other hand, when the turbine speed exceeds the rated speed, the valve The opening degree control signal becomes a closing command, and the speed fluctuation that the control valve 3 and the intercept valve 8 are closed and the turbine speed is decreased occurs.
[0004]
[Problems to be solved by the invention]
SUMMARY OF THE INVENTION An object of the present invention is to provide a turbine control device suitable for stably operating a plant by preventing mutual interference between an adjusting valve and an intercept valve in speed control of an intercept valve when a turbine is at a rated speed after a load is cut off. is there.
[0005]
[Means for Solving the Problems]
The above object is achieved by a high-pressure turbine driven by steam generated in a boiler and passing through a control valve, and a medium-pressure turbine driven by reheated steam obtained by reheating steam after driving the high-pressure turbine and passing through an intercept valve. And a turbine control device for controlling a power plant having a high-pressure bypass valve for bypassing the high-pressure turbine and a low-pressure bypass valve driven by steam after driving the medium-pressure turbine. This is achieved by controlling the speed by the intercept valve when the turbine speed is at the rated speed while the valve is fully closed .
Further, this is achieved by providing a speed correction gain switching means and switching the speed gain from the normal gain to the speed correction gain after a certain period of time from the occurrence of the load interruption using the load interruption signal.
Further, the present invention is achieved by providing an acceleration relay re-operation preventing means to prevent a re-operation of the acceleration relay due to a rise in turbine speed when the intercept valve is restarted after the intercept valve is suddenly closed when the load is cut off.
[0006]
[Action]
According to the present invention, in the speed control by the intercept valve after the load is cut off, a stable plant operation by the intercept valve can be realized without interference between the intercept valve and the control valve when the turbine speed is the rated speed .
Further, by setting an optimum speed control gain suitable for the intercept valve speed control, stable intercept valve control can be performed.
In addition, after the intercept valve suddenly closes when the load is cut off, by preventing the acceleration relay from restarting due to a rise in turbine speed when resuming, it is possible to prevent the inadvertent sudden close operation of the intercept valve, and use a stable intercept valve. Speed control becomes possible.
[0007]
【Example】
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows an embodiment of a turbine control device according to the present invention. In this embodiment, the same reference numerals as those in the conventional example of FIG. In FIG. 1, reference numeral 300 denotes an opening / closing operation suppressing unit of the control valve 3, 400 denotes a speed correction gain switching unit after the load is cut off, and 500 denotes an acceleration relay re-operation preventing unit for preventing an inadvertent sudden closing operation of the intercept valve 8. . The opening / closing operation suppressing unit 300 of the control valve 3 controls the turbine after the load is cut off by controlling the speed by the intercept valve 8, and keeps the control valve 3 in the fully closed position, that is, suppresses the opening / closing operation of the control valve. The speed correction gain switching unit 400 after the load cutoff performs switching after governor runback accompanying the load cutoff, and switches to an appropriate speed control gain suitable for speed control of the intercept valve 8. The acceleration relay re-operation prevention unit 500 for preventing the inadvertent sudden closing operation of the intercept valve 8 restarts after the intercept valve 8 suddenly closes when the load is cut off, and the actual turbine speed rises and the actual acceleration is set in advance. When the acceleration becomes higher than the set acceleration value, the acceleration relay is prevented from being reactivated due to a rise in turbine speed, and the inadvertent sudden closing operation of the intercept valve 8 is prevented.
[0008]
FIG. 3 shows details of the opening / closing operation suppressing unit 300 of the control valve 3. The opening / closing operation suppressing unit 300 of the control valve 3 includes a zero signal generation circuit 312, a flip-flop 316, and a changeover switch 360. 317 is a load cutoff signal. 323 is a turbine trip signal for stopping operation. Reference numeral 324 indicates a main circuit breaker (generator) signal. In FIG. 3, the same reference numerals as those in the conventional example of FIG. 6 represent the same object.
The operation of the opening / closing operation suppressing section 300 of the control valve 3 will be described with reference to FIG. The rated turbine speed is set in the signal generator 600. During normal operation, the deviation from the turbine actual speed signal 620 is obtained by the subtractor 641, multiplied by the speed adjustment rate 602, and the load setter 604 The position and the adder 642 are added. At this time, since the position of the load limiter 603 is at the fully open position, the output signal of the adder 642 is selected by the low value selection circuit 607. The flip-flop 316 is in the reset state because it is in the normal operation state, and connects the changeover switch 360 to the low value selection circuit 607. Accordingly, the output signal of the low value selection circuit 607 passes through the control valve opening characteristic 608, the intercept valve opening characteristic 610, the control valve opening speed change rate limit 609, and the intercept valve opening speed change rate limit 611, respectively. It is output to the valve 3 and the intercept valve 8 as a valve opening command. The control valve 3 and the intercept valve 8 are controlled by a deviation between the respective valve opening command and the actual valve opening of the control valve 3 and the actual valve opening of the intercept valve 8.
Now, when load interruption occurs (point A in FIG. 9), the turbine speed (speed) increases (FIG. 9A), the flip-flop 605 is set by the load interruption detection signal 621, and the flip-flop 605 is set. Outputs the governor run-back signal 651 to the load setting unit 604, and sets the flip-flop 316. The flip-flop 316 outputs “1” as the load cutoff signal 317, and the signal causes the position of the load setting unit 604 to run back (FIG. 9, (e)), and the changeover switch 360 operates to select a low value. Switching from the circuit 607 to the zero signal generation circuit 312, the zero signal generator 312 outputs a fully closed position signal as an adjustable valve opening control signal, passes through an adjustable valve opening characteristic 608 and an adjustable valve opening speed change rate limit 609, A valve opening fully closed position command is output to the control valve 3. Thereby, the control valve 3 is controlled to the fully closed position (FIG. 9, (d)). On the other hand, in the intercept valve 8, the output signal of the low value selection 607 in front of the changeover switch 360 becomes an intercept valve opening control signal, the intercept valve 8 is opened, and after the load is cut off, the intercept valve speed is controlled (see FIG. 9, (b)). The turbine trip signal 323 for stopping the operation and the all-valve closing signal 324 are signals for stopping the operation. When this signal is output, the flip-flop 316 is reset, and the changeover switch 360 is turned off by the low value selection circuit 607. Instead, the operation is stopped by means not shown. Further, when the closing signal “1” of the main circuit breaker (generator) signal 325 is output, the flip-flop 316 is reset, the changeover switch 360 is switched to the low value selection circuit 607, and the normal operation state is set.
Further, as another means for fully closing the control valve 3, a load cutoff signal 317 is applied to the load limiter 603, and the load limiter 603 is run back to a point a corresponding to the fully closed position of the control valve 3 in FIG. Thus, the control valve 3 can be fully closed.
As described above, by providing the opening / closing operation suppressing section 300 of the control valve 3, the control valve 3 is controlled to the fully closed position when the load is interrupted, and the intercept valve 8 is controlled by the opening control signal of the intercept valve 8. Since the intercept valve speed control is performed, mutual interference between the control valve and the intercept valve can be prevented, and the plant can be stably operated.
[0009]
FIG. 4 shows details of the speed correction gain switching unit 400 after the load is cut off. The speed correction gain switching unit 400 checks whether or not the delay timer (time delay) 413 and the control valve 3 are fully closed. When the control valve 3 is fully closed, the comparator 414 that outputs “1” and the flip-flop 415, a timer 417, a timer 418, a changeover switch 461, a speed correction gain setting device 470, a normal gain setting device 480, and a speed correction gain signal generator 490, and 491 indicates a speed correction gain signal. In FIG. 4, the same reference numerals as those in the conventional example shown in FIGS. 3 and 6 represent the same object.
The operation of the speed correction gain switching section 400 will be described with reference to FIG. During normal operation, the flip-flop 605 is in a reset state, and the changeover switch 360 is connected to the low value selection circuit 607. Now, when load interruption occurs (point A in FIG. 9), the turbine speed (speed) increases (FIG. 9, (a)), and the flip-flop 605 is output by the load interruption detection signal 621 as described in FIG. Is set, and the flip-flop 316 is set by the set signal of the flip-flop 605. The flip-flop 316 outputs “1” as the load cutoff signal 317, and the signal causes the position of the load setting unit 604 to run back (FIG. 9, (e)), and the changeover switch 360 operates to select a low value. Switching from the circuit 607 to the zero signal generation circuit 312, the zero signal generator 312 outputs a fully closed position signal as an adjustable valve opening control signal, passes through an adjustable valve opening characteristic 608 and an adjustable valve opening speed change rate limit 609, A valve opening fully closed position command is output to the control valve 3. Thereby, the control valve 3 is controlled to the fully closed position (FIG. 9, (d)). On the other hand, the load cutoff signal 317 is applied to the timer 418 connects the selector switch 461 to the speed correction gain setter 470 after a predetermined time (Fig. 9, T ₀ sec + T ₁ s), the speed correction gain signal generator 490 The speed correction gain signal 491 is output to the speed correction gain 402, and the speed correction gain (FIG. 9, (f)) when the load is cut off from the normal gain (FIG. 9, (f) .alpha. Percent) of the normal gain setting unit 480 to the bumpless. switch to β percent).
Further, as another means for switching the speed correction gain after the load is cut off, the condition that the main breaker (generator) is in the open state, that is, the load cut off state, and the control valve 3 is fully closed can be used. In this case, the main circuit breaker (generator) signal 325 is an open signal “0”, and the open signal “0” is input to the AND circuit via the knot circuit and the delay timer 413, while the valve of the control valve 3 is The opening degree fully closed position command is input to the comparator 414 via B, and the fully closed signal “1” is input from the comparator 414 to the AND circuit. The output of the AND circuit sets the flip-flop 415 is connected after a certain period of time through a timer 417 the switch 461 to the speed correction gain setter 470 (FIG. 9, T ₀ sec + T ₁ s), the speed correction gain The speed correction gain signal 491 is output from the signal generator 490 to the speed correction gain 402, and the normal gain (FIG. 9, (f) α percent) of the normal gain setting unit 480 is used to output the speed correction gain when the load is cut off to the bumpless press (see FIG. 9). 9, (f) β percent).
On the other hand, when the turbine trip signal 323 or the all-valve-close signal 324 for stopping the operation is output, the flip-flop 316 is reset, the changeover switch 360 is switched to the low value selection circuit 607, and the flip-flop 415 is reset. The changeover switch 461 is switched to the normal gain setting device 480, and the operation is stopped by means not shown. When the closing signal of the main circuit breaker (generator) signal 325 is output, the flip-flop 316 is reset, the changeover switch 360 is switched to the low value selection circuit 607, and the flip-flop 415 is reset, and the changeover switch 461 is set. Is switched to the normal gain setting device 480 to enter the normal operation state.
As described above, by providing the speed correction gain switching unit 400 after the load is cut off, it is possible to set an optimum speed control gain suitable for the intercept valve speed control with the switching of the governor runback at the time of load cut off. Stable intercept valve control becomes possible.
Further, by combining the speed correction gain switching unit 400 in FIG. 4 with the opening / closing operation suppressing unit 300 of the control valve 3 in FIG. 3, more stable plant operation is possible.
[0010]
FIG. 5 shows details of the acceleration relay re-operation prevention unit 500 for preventing the inadvertent sudden closing operation of the intercept valve 8. The acceleration relay re-operation prevention unit 500 outputs "1" when the output of the differentiator 550 is larger than the acceleration set value, and operates an acceleration relay (not shown). A comparator 551 for rapidly closing the intercept valve 8, a dedicated comparator 552 for comparing the actual turbine speed with the set turbine speed, and a load interruption for comparing the actual turbine speed with the turbine speed set for the load interruption. A time-only comparator 553 includes a timer 554 that operates after a predetermined time. Further, in FIG. 5, the same reference numerals as those in the conventional examples in FIGS. 3, 4 and 6 represent the same objects.
Here, the acceleration relay detects that an increase change rate (acceleration) of the actual turbine speed is equal to or higher than a specified value, and furthermore, when the actual turbine speed is equal to or higher than the acceleration relay operation detection speed, increases the turbine speed. The intercept valve is suddenly closed for the purpose of prevention.
The operation of the acceleration relay re-operation prevention unit 500 will be described with reference to FIG. During normal operation, the actual turbine speed signal 620 is input from A to the differentiator 550, and the actual turbine speed is converted into an actual acceleration. This actual acceleration is compared with a preset acceleration set value in the comparator 551. When the actual acceleration is lower than the acceleration set value, there is no output from the comparator 551 and the acceleration relay is not operated. Now, when load interruption occurs (point A in FIG. 9), the actual turbine speed increases (FIG. 9, (a)), the actual acceleration becomes higher than the acceleration set value of the comparator 551, and the actual turbine speed decreases. When the turbine speed set in the normal-time dedicated comparator 552 (FIG. 9, (g) c percent) is exceeded, the AND circuit outputs a rapid closing signal "1" of the intercept valve 8 to the acceleration relay (FIG. 9, ( c) Point B), the intercept valve 8 is rapidly closed (FIG. 9, (b)). However, after the intercept valve 8 is suddenly closed, the opening control is performed again, and when the turbine speed increases, the acceleration relay may operate again. Therefore, when the speed correction gain is switched after the load cutoff described with reference to FIG. the load cutoff signal 317 is input to the timer 554, after the runback completion of a certain time after or load setter 604 (FIG. 9, T ₂ seconds), the blocking output of the normal exclusive comparator 552 by the NOT circuit at the same time, The load-cutoff-dedicated comparator 553 switches to the turbine speed (FIG. 9, (g) d percent) set for load-cutoff, and outputs a quick-close signal "0" of the intercept valve 8 from the AND circuit, thereby turning on the acceleration relay. The re-operation is prevented, and the rapid closing operation of the intercept valve 8 is prevented. In this way, it is possible to prevent the acceleration relay from re-operating due to a rise in turbine speed when the intercept valve 8 is suddenly closed and restarted after the load is cut off. This prevents inadvertent sudden closing of the intercept valve 8 and enables stable speed control by the intercept valve 8.
3, 4, and 5 automatically shift to load cutoff speed control after load cutoff, but shift to normal control at the time of uniform speed control or manual operation of the load setting unit 504.
[0011]
【The invention's effect】
As described above, according to the present invention, in the speed control by the intercept valve after the load is cut off, stable plant operation by the intercept valve can be realized without interference between the intercept valve and the control valve when the turbine speed is the rated speed. .
Further, by setting an optimum speed control gain suitable for the intercept valve speed control, stable intercept valve control can be performed.
In addition, after the intercept valve suddenly closes when the load is cut off, it prevents accidental restart of the acceleration relay due to a rise in turbine speed when the intercept valve is restarted. Control becomes possible.
[Brief description of the drawings]
FIG. 1 shows an embodiment of a turbine control device according to the present invention.
FIG. 2 shows a system diagram of a steam turbine system having a turbine bypass system.
FIG. 3 shows details of an opening / closing operation suppressing section of the control valve of the present embodiment.
FIG. 4 shows details of a speed correction gain switching unit after load interruption according to the present embodiment.
FIG. 5 shows details of an intercept valve sudden closing operation prevention unit of the present embodiment.
FIG. 6 shows a conventional turbine control device.
FIG. 7 shows the opening / closing characteristics of the intercept valve 8 and the control valve 3.
FIG. 8 shows characteristics of a turbine speed and a valve opening degree when a load is cut off.
FIG. 9 shows a control operation after load interruption according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Boiler 2 Main steam stop valve 3 Control valve 4 High pressure turbine 5 Check valve 6 Reheater 7 Reheat steam stop valve 8 Intercept valve 9 Intercept bypass valve 10 Medium pressure turbine 11 Low pressure turbine 12 Condenser 13 Generator 14 High pressure Bypass valve 15 Low-pressure bypass valve 18 Heater 19 Pump 21 Main steam system 22 Reheat system 23 Turbine bypass system 24 Steam system 25 Condensate system 300 Opening / closing operation suppression unit 400 for control valve 3 Speed correction gain switching unit 500 after load cutoff Prevention of sudden closing operation of intercept valve 8

Claims (7)

A high-pressure turbine generated in a boiler and driven by steam passing through a regulating valve; a medium-pressure turbine driven by reheated steam obtained by reheating steam after driving the high-pressure turbine and passing through an intercept valve; In a turbine control device for controlling a power plant having a high-pressure bypass valve that bypasses a high-pressure turbine and a low-pressure bypass valve driven by steam after driving the intermediate-pressure turbine,
When the load cutoff, while the regulating valve with a load cutoff signal is fully closed, the turbine controller turbine speed and performs the speed control by the intercept valve at the rated speed. 2. The turbine control device according to claim 1, further comprising switching means for switching from a control valve opening control signal during normal operation to a control valve fully closed position signal using a load cutoff signal. 2. The turbine control device according to claim 1, further comprising means for causing the load limiter to run back to the fully closed position of the control valve using the load cutoff signal. A speed correction gain switching means according to any one of claims 1 to 3, wherein the speed gain is switched from the normal gain to the speed correction gain after a predetermined time from the occurrence of load interruption by using a load interruption signal. Turbine control device. A speed correction gain switching means according to any one of claims 1 to 4, wherein a switching time of a generator main circuit breaker and a valve opening degree fully closed position command of a control valve are used for a fixed time from the occurrence of load interruption. A turbine control device for switching a speed gain from a normal gain to a speed correction gain later. An acceleration relay re-operation preventing means according to any one of claims 1 to 5, wherein the acceleration relay is restarted after the intercept valve is suddenly closed when the load is cut off, and the acceleration relay is restarted due to a rise in turbine speed. A turbine control device characterized by the above-mentioned. 7. The acceleration relay re-operation prevention means according to claim 6, wherein the differentiator converts the actual turbine speed into acceleration, a comparator that compares the acceleration with a preset acceleration set value, and a turbine speed that is set when the load is cut off. A normal time comparator for comparing the actual turbine speed with the actual turbine speed, a load interruption dedicated comparator for comparing the actual turbine speed with the turbine speed set for load interruption, and a timer that operates after a predetermined time. Characteristic turbine control device.

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