JP2016073129A - Cooling gas temperature control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To more quickly control a temperature of cooling gas for cooling a generator so as to prevent the temperature from overshooting as much as possible from start-up time of the generator until a stable state thereof.SOLUTION: A cooling gas temperature control device comprises: a determination module 20 determining a lower limit of valve opening of a control valve 8 for adjusting a flow rate of cooling water 1 cooling hydrogen gas 3 in accordance with process conditions in a generator 2; a PID arithmetic section 12 performing a PID operation on the basis of a difference between a current value of a temperature of the hydrogen gas and a setting value set beforehand related to the temperature of the hydrogen gas and determining an adjustment amount of the valve opening; and an adder 13 adding the adjustment amount determined by the PID arithmetic section 12 to the lower limit of the valve opening determined by the determination module 20 and controlling the valve opening by applying addition results as an operation amount to the control valve 8.SELECTED DRAWING: Figure 1

Description

  Embodiments described herein relate generally to a cooling gas temperature control device for controlling the temperature of a cooling gas for cooling a generator from when the generator is started until it reaches a stable state.

  Conventionally, this kind of cooling gas temperature control is performed by cooling the cooling gas for cooling the generator with cooling water. Specifically, the temperature of the cooling gas is changed by changing the valve opening of the control valve that adjusts the amount of cooling water based on PID control based on the difference between the current value of the cooling gas temperature and the set value. It is controlled.

  PID control increases or decreases an output signal (valve opening command value), which is an operation amount MV to the operation end, according to the difference between the process value PV and the set value SV, and the deviation between the process value PV and the set value SV is increased. This control is as close to 0 (zero) as possible. Generally, when hydrogen gas is used as the cooling gas, control of the control valve is started when the temperature of the hydrogen gas exceeds a set value.

JP 2000-350413 A

  However, such conventional cooling gas temperature control has the following problems.

  That is, in the conventional cooling gas temperature control, since the timing from the generator start time t1 to the control valve control start t2 is late, the cooling gas temperature overshoots as shown in FIG. An alarm may be generated.

  The cause of this overshoot is that the operation of the control valve cannot follow the sudden rise in the cooling gas temperature.

  That is, when the turbine of the generator rotates, friction with ambient air is generated, and rotational energy is converted into heat energy. In general, the windage loss increases in proportion to the cube of the rotational speed of the turbine, and the temperature rise rate of the cooling gas suddenly changes as indicated by the temperature rise rate sudden change point a in FIG.

  However, the control valve control start t2 in the conventional cooling gas temperature control is not performed at the temperature rise rate sudden change point a but until the temperature of the cooling gas exceeds the set value SV.

  As described above, since the control valve control start t2 is made not at the temperature change rate sudden change point a but at a timing exceeding the set value SV, the operation of the control valve cannot follow the rise in the cooling gas temperature, and the cooling The gas temperature overshooted and stable control could not be performed.

  In order to avoid such an overshoot, for example, it is conceivable to take measures such as increasing the proportional gain or shortening the integration time so that the cooling gas temperature reaches the set value SV earlier. .

  However, in that case, the manipulated variable MV (valve opening command value) based on the difference between the current temperature PV of the cooling gas and the set value SV of the cooling gas becomes large, and therefore the cooling gas temperature may hunt. Get higher.

  In general, there is a possibility that a hydrogen gas temperature high alarm may be generated due to a generator overload, a high coolant temperature, a malfunction of the control valve, etc., but the alarm is generated in a state from the start t1 to the stable state t3. This is not expected. Therefore, when an alarm is generated during the period from the start time t1 to the stable state t3, there is a possibility that it is necessary to confirm where the trouble is. It is necessary to devise a solution to remove the trouble or anxiety factor.

  In addition, overshooting at every start-up may be considered as not being properly controlled. Therefore, a more reliable control device is required.

  The present invention has been made in view of such circumstances, and controls the temperature of the cooling gas more quickly and as little as possible from the start of the generator until it becomes stable. It is an object of the present invention to provide a cooling gas temperature control device capable of performing the following.

  Patent Document 1 discloses a technique for applying PID calculation to control the temperature of the cooling gas. However, the technique disclosed in Patent Document 1 switches the set value according to each operation state in order to improve controllability, whereas the cooling gas temperature control device according to the present invention performs transient operation even at startup. Even in the state, it is different in that it can be controlled without having to switch the set value.

  In order to achieve the above object, the present invention takes the following measures.

  The cooling gas temperature control device of the embodiment is a device for controlling the temperature of the cooling gas for cooling the generator from the time of starting the generator until it becomes stable, and cooling for cooling the cooling gas The lower limit value of the valve opening of the control valve for adjusting the flow rate of water is set in advance with respect to the determining means that determines the process conditions in the generator, the current value of the temperature of the cooling gas, and the temperature of the cooling gas. PID calculation means for performing a PID calculation based on the difference from the set value and determining the adjustment amount of the valve opening, and the adjustment amount determined by the PID calculation means to the lower limit value of the valve opening determined by the determination means And a valve opening degree control means for controlling the valve opening degree by applying the addition result to the control valve as an operation amount.

It is a conceptual diagram which shows the structural example of the cooling gas temperature control apparatus which concerns on 1st Embodiment. It is a flowchart which shows the operation example of the cooling gas temperature control apparatus which concerns on 1st Embodiment. It is a conceptual diagram which shows an example of the control characteristic of the cooling gas temperature by the cooling gas temperature control apparatus which concerns on 1st Embodiment. It is a conceptual diagram which shows the structural example of the cooling gas temperature control apparatus which concerns on 2nd Embodiment. It is a conceptual diagram which shows an example of the control characteristic of the cooling gas temperature by the cooling gas temperature control apparatus which concerns on 2nd Embodiment. It is a conceptual diagram which shows the structural example of the cooling gas temperature control apparatus which concerns on 3rd Embodiment. It is a conceptual diagram which shows an example of the control characteristic of the cooling gas temperature by the cooling gas temperature control apparatus which concerns on 3rd Embodiment. It is a conceptual diagram which shows the structural example of the cooling gas temperature control apparatus which concerns on 4th Embodiment. It is an example of the function memorize | stored in the function generator applied to the cooling gas temperature control apparatus which concerns on 4th Embodiment. It is a conceptual diagram which shows an example of the control characteristic of the cooling gas temperature by the cooling gas temperature control apparatus which concerns on 4th Embodiment. It is a conceptual diagram which shows an example of the partial structure of the cooling gas temperature control apparatus which concerns on 5th Embodiment. It is a conceptual diagram which shows an example of the partial structure of the cooling gas temperature control apparatus which concerns on 6th Embodiment. It is a conceptual diagram of the control characteristic of the cooling gas temperature by the prior art to which PID control is applied.

  Below, the cooling gas temperature control apparatus of each embodiment of this invention is demonstrated with reference to drawings. In each embodiment, as an example, the cooling gas is hydrogen gas.

[First Embodiment]
FIG. 1 is a conceptual diagram illustrating a configuration example of a cooling gas temperature control apparatus 100 according to the first embodiment.

  That is, the cooling gas temperature control apparatus 100 according to the first embodiment controls the temperature of the hydrogen gas 3 that is a cooling gas for cooling the generator 2 from the time of starting the generator 2 until it becomes stable. It is a device for doing.

  This apparatus 100 sets the lower limit value of the valve opening of the control valve 8 for adjusting the flow rate of the cooling water 1 introduced into the hydrogen gas coolers 4, 5, 6, 7 for cooling the hydrogen gas 3, as a generator 2, a determination module 20 that determines according to the process conditions in 2, a PID calculator 12, and an adder 13.

  Process conditions are the rotation speed of the turbine of the generator 2, and the temperature of the hydrogen gas 3, for example. In order to grasp these process conditions, the determination module 20 includes a rotational speed measuring device 10 for measuring the rotational speed of the generator 2 and a temperature measuring device 11 for measuring the temperature of the hydrogen gas 3. Yes.

  The determination module 20 further includes a high comparator 14 that outputs an “ON” signal when the rotational speed measured by the rotational speed measuring instrument 10 exceeds a predetermined rotational speed, and the temperature measured by the temperature measuring instrument 11. Is provided with a high comparator 15 that outputs an “ON” signal when the temperature exceeds a predetermined temperature.

  For example, when it is known based on the results that the temperature of the hydrogen gas 3 changes suddenly at a turbine rotational speed of 900 rpm, the high comparator 14 is turned “ON” when the rotational speed measuring instrument 10 measures the turbine rotational speed of 900 rpm. "The signal is output.

  For example, when it is known based on the results that the temperature rise rate of the hydrogen gas 3 changes rapidly from 36 ° C., when the temperature measuring device 11 measures 35 ° C., the high comparator 15 turns on the “ON” signal. Is output.

  Note that the predetermined rotation speed and the predetermined temperature are not limited to the above-described values, and may be appropriately set appropriately so as to obtain optimum control characteristics according to the operating state.

  The determination module 20 further includes a logical operation unit (OR) 16, a bumpless transfer 17, and lower limit valve opening setting units 18 and 19. A lower value (for example, 0%) is preset in the lower limit valve opening setting device 19 as a lower limit value of the valve opening of the control valve 8, and the lower valve opening setting device 18 includes a control valve. As a lower limit value of the valve opening degree of 8, a high value (for example, 5%) is set in advance. When the generator 2 is started up, the bumpless transfer 17 is set by default so as to select the lower limit valve opening setting device 19 (that is, a lower lower limit value).

  The logical operation unit (OR) 16 inputs an “ON” signal to the bumpless transfer 17 when an “ON” signal is output from either the high comparator 14 or the high comparator 15. Thereby, the bumpless transfer 17 sets the lower limit valve opening for determining the lower limit value of the valve opening of the control valve 8 from the value (for example, 0%) set by the lower limit valve opening setting unit 19. It switches so that it may raise to the value (for example, 5%) set by the lower limit valve opening setting device 18. FIG. Then, the switched lower limit valve opening (in this example, 5%) and its rate are input to the adder 13. In this embodiment, the rate is 100% / second as an example. The configuration of the adder 13 will be described later.

  The lower limit valve opening is not limited to the above-described value, and may be set as appropriate so as to obtain optimal control characteristics according to the operating state.

  On the other hand, the PID calculator 12 performs a PID calculation based on the difference between the current value PV of the temperature of the hydrogen gas 3 and a set value SV that is set in advance with respect to the temperature of the hydrogen gas 3, and determines the valve opening degree of the control valve 8. The adjustment amount is determined, and the determined adjustment amount is input to the adder 13. For this reason, the cooling gas temperature control apparatus 100 includes a temperature measuring device 9 for measuring the temperature of the hydrogen gas 3. The temperature measuring device 9 inputs the measured temperature to the PID calculator 12. The temperature measuring device 9 and the temperature measuring device 11 may be the same or different.

  The adder 13 adds the adjustment amount determined by the PID calculator 12 to the lower limit valve opening input from the bumpless transfer 17 and uses the addition result as an operation amount MV (valve opening command value) as a control valve. 8 is used to control the valve opening of the control valve 8. Since the rate is 100% / second, 100% of the manipulated variable MV (valve opening command value) is applied to the control valve per second.

  Next, the operation of the cooling gas temperature control apparatus 100 according to the first embodiment configured as described above will be described with reference to the flowchart of FIG.

  When the generator 2 is started (S1), the rotational speed of the turbine of the generator 2 is measured by the rotational speed measuring device 10, and the temperature of the hydrogen gas 3 is measured by the temperature measuring device 11 (S2).

  Then, when the rotational speed measured by the rotational speed measuring device 10 is equal to or higher than a predetermined rotational speed (for example, 900 rpm) and an “ON” signal is output from the high comparator 14, or measured by the temperature measuring device 11. When the temperature becomes equal to or higher than a predetermined temperature (for example, 35 ° C. or higher) and the “ON” signal is output from the high comparator 15 (S3: Yes), the logic unit (OR) 16 causes the bumpless transfer 17 The "ON" signal is input to (S4).

  As a result, the lower limit valve opening of the control valve 8 is set by the lower limit valve opening setting unit 18 from the value (for example, 0%) set by the lower limit valve opening setting unit 19 by the bumpless transfer 17. It is switched so as to increase the value (for example, 5%) that has been set (S5). Then, the switched lower limit valve opening (in this example, 5%) and the rate (in this example, 100% / second) are input to the adder 13 (S6).

  Further, the temperature of the hydrogen gas 3 measured by the temperature measuring device 9 is input to the PID calculator 12 (S7). Then, the PID calculator 12 performs a PID calculation based on the difference between the current value PV of the temperature of the hydrogen gas 3 input by the temperature measuring device 9 and a set value SV set in advance with respect to the temperature of the hydrogen gas 3. The amount of adjustment of the valve opening of the control valve 8 is determined and input to the adder 13 (S8).

  In the adder 13, the adjustment amount determined by the PID calculator 12 is added to the lower limit valve opening inputted from the bumpless transfer 17, and the addition result is obtained as an operation amount MV (valve opening command value). Is applied to the control valve 8 to control the valve opening of the control valve 8 (S9).

  On the other hand, in step S3, the rotational speed measured by the rotational speed measuring device 10 does not exceed a predetermined rotational speed (for example, 900 rpm), and the temperature measured by the temperature measuring device 11 is the predetermined temperature (for example, 35). When the temperature does not exceed (° C. or higher) (S3: No), the process returns to step S2.

  In the cooling gas temperature control apparatus according to the first embodiment, by performing such control, as shown in the control characteristic example of FIG. 3, the temperature increase rate sudden change point a and the control start t2 have the same timing. Compared with the prior art shown in FIG. 13, the control start of the control valve 8 can be appropriately accelerated, so that the temperature rise of the hydrogen gas 3 due to windage is suppressed, and the stable state is reached from the time t1 when the generator 2 is started. Until t3, the temperature overshoot of the hydrogen gas 3 can be more relaxed and more stable control can be performed as compared with FIG.

[Second Embodiment]
The second embodiment is a modification of the first embodiment.

  FIG. 4 is a conceptual diagram illustrating a configuration example of the cooling gas temperature control device 200 according to the second embodiment.

  FIG. 4 is different from FIG. 1 only in that a bumpless transfer 17 'capable of changing the rate is provided instead of the bumpless transfer 17 having a fixed rate. Therefore, here, only differences from the first embodiment will be described, and the same parts as those in FIG.

  The bumpless transfer 17 described in the first embodiment is fixed at a rate of 100% / sec. Therefore, when the lower limit value of the valve opening is increased, for example, as shown in FIG. At the control start t2, the operation amount MV (valve opening command value) is added stepwise.

  However, when the manipulated variable MV (valve opening command value) is added stepwise in this way, the control valve 8 is suddenly opened, and the temperature of the hydrogen gas 3 is once lowered as shown in FIG. There is also a possibility that the follow-up to the set value SV may be delayed.

  As described above, when the rate at which the operation amount MV (valve opening command value) is applied is so large as to adversely affect the temperature control, and instead acts as a disturbance element, the rate of the bumpless transfer 17 having a fixed rate is set. Instead, as shown in FIG. 4, a rate changeable bumpless transfer 17 ′ is applied, and the rate at which the manipulated variable MV (valve opening command value) is added is, for example, 0.1% / second. Lower.

  In this way, the operation amount MV (valve opening command value) is added more slowly than in the first embodiment by reducing the rate.

  An example of control characteristics by the cooling gas temperature control apparatus 200 according to the second embodiment configured as described above is shown in FIG. That is, in FIG. 5, the stepped rise of the operation amount MV (valve opening instruction value) as seen in FIG. 3 is eliminated, and the operation amount MV (valve opening instruction value) is changed from the control start t2 to the time t4. Until constantly added.

  According to the cooling gas temperature control apparatus 200 according to the present embodiment having such a configuration, the operation amount MV (valve opening instruction value) can be slowly added, and the control valve 8 can be controlled by sudden opening. Can be prevented from becoming unstable.

  Note that the rate of 0.1% / second is an example, and may be appropriately changed and set so as to obtain optimum control characteristics.

[Third Embodiment]
FIG. 6 is a conceptual diagram illustrating a configuration example of the cooling gas temperature control device 300 according to the third embodiment.

  FIG. 6 is different in that a determination module 30 is provided instead of the determination module 20 in FIG. Therefore, here, only differences from the first embodiment will be described, and the same parts as those in FIG.

  That is, when the temperature increase rate of the hydrogen gas 3 is higher than a predetermined temperature increase rate, the determination module 30 determines the lower limit value of the valve opening of the control valve 8 to be higher than the current value. .

  In order to realize this, the determination module 30 includes a first-order lag device 21, a deviation calculator 22, and a high comparator 23.

  When measuring the temperature of the hydrogen gas 3, the temperature measuring device 9 sends the measurement result to the first-order lag device 21 and the deviation calculator 22.

  The first-order lag device 21 sends the measurement result sent from the temperature measuring device 9 to the deviation calculator 22 after a certain time (for example, after 5 minutes).

  Thereby, the deviation calculator 22 acquires both the current temperature of the hydrogen gas 3 and the temperature before a certain time (for example, 5 minutes before), and whether or not the rate of temperature increase has suddenly changed from these temperatures. Determine whether.

  For example, when the temperature of the hydrogen gas 3 is known to change suddenly when the temperature of the hydrogen gas 3 rises by 5 ° C. or more in 5 minutes, the deviation calculator 22 determines that the temperature of the hydrogen gas 3 is 3 ° C. in 5 minutes, for example. When it rises above, it is programmed in advance to determine that it is approaching the temperature rise sudden change point. Accordingly, the deviation calculator 22 causes the high comparator 23 to output an “ON” signal to the bumpless transfer 17 when the temperature of the hydrogen gas 3 rises by 3 ° C. or more in 5 minutes, for example.

  Thereby, the bumpless transfer 17 operates as described in the first embodiment, and the lower limit valve opening degree that determines the lower limit value of the valve opening degree of the control valve 8 is set by the lower limit valve opening degree setting device 19. The value is increased from the set value (for example, 0%) to the value (for example, 5%) set by the lower limit valve opening setting device 18.

  An example of control characteristics by the cooling gas temperature control device 300 according to the third embodiment configured as described above is shown in FIG. Since the control start t2 can be performed before the temperature rise sudden change point is reached, overshoot can be reduced. Note that the time delayed by the constant delay device 21 and the temperature increase rate are not limited to the above-described values, but may be appropriately changed and set according to the operating state so as to obtain optimum control characteristics. You can do it. For example, when the rate of temperature increase differs depending on the turbine acceleration rate, the valve opening of the lower limit valve opening setting unit 18 may be changed so that optimum control characteristics can be obtained.

  Further, when the temperature decrease as shown in FIG. 7d is remarkable, the bumpless transfer 17 ′ is applied instead of the bumpless transfer 17, and the manipulated variable MV (valve opening command value) is set. If it is added slowly, the temperature drop as shown in d of FIG. 7 is alleviated, and the control characteristics can be improved as shown in the tendency shown in FIG. 5, for example.

[Fourth Embodiment]
FIG. 8 is a conceptual diagram illustrating a configuration example of the cooling gas temperature control device 400 according to the fourth embodiment.

  FIG. 8 differs in that a determination module 40 is provided instead of the determination module 20 in FIG. Therefore, here, only differences from the first embodiment will be described, and the same parts as those in FIG.

  That is, the determination module 40 determines the lower limit value of the valve opening according to a function set in advance according to the difference between the process value in the generator 2 and a set value set in advance with respect to the process value.

  In order to realize this, the determination module 40 eliminates the temperature measuring device 11, the high comparator 15, the logical operation unit (OR) 16, and the lower limit valve opening setting device 18 of the determination module 20 of FIG. A set value setter 41, a deviation calculator 42, and a function generator 43 are provided. This is a configuration in an example in which the process value is the temperature of the hydrogen gas 3.

  In this case, the temperature of the hydrogen gas 3 in the stable state t3 (for example, 45 ° C.) is set in the set value setter 41.

  The deviation calculator 42 receives the temperature of the hydrogen gas 3 measured by the temperature measuring device 9. Then, this temperature is subtracted from the temperature set in the set value setter 41, and the result is output to the function generator 43.

  For example, a function as shown in FIG. 9 is stored in the function generator 43, and the valve opening command value is output to the bumpless transfer 17 in accordance with the result from the deviation calculator 42. The function as shown in FIG. 9 is an example generated in advance based on the results, and is not limited to this function.

  The rotational speed measuring device 10 measures the rotational speed of the turbine, and the high comparator 14 outputs an “ON” signal when the rotational speed measured by the rotational speed measuring device 10 exceeds a predetermined rotational speed. Output to the press transfer 17.

  When the bumpless transfer 17 receives the “ON” signal from the high comparator 14, the lower limit value of the valve opening of the control valve 8 is set to the value set by the lower limit valve opening setting device 19 (for example, 0%). To the valve opening command value output by the function generator 43. The rate is also set to 0.1% / second.

  According to the cooling gas temperature control apparatus 400 according to the present embodiment, with such a configuration, the control valve 8 is controlled by performing feedforward control based on the difference between the set value of the temperature of the hydrogen gas 3 and the current value. It can be opened or closed in advance.

  In general, in the feedback control, when a disturbance factor that disturbs the control occurs, for example, when the cooling water temperature suddenly rises or the internal temperature suddenly rises due to an overload of the generator 2, a PID calculation is performed unless a deviation occurs. In some cases, it is difficult to control the disturbance.

  On the other hand, in the feedforward control, when the disturbance factors described above occur, the correction operation can be performed in advance to eliminate the influence before the influence of the disturbance of temperature, etc. There is an advantage that the controllability is superior to the case of only feedback control.

  The cooling gas temperature control apparatus 400 according to the present embodiment can be implemented by combining the feedforward control that is performed by the determination module 40 to add the operation amount in advance and the feedback control that is performed by the PID computing unit 12. .

  As a result, as shown in FIG. 10, an example of the control characteristics prevents the temperature overshoot of the hydrogen gas 3 and realizes a stable control state even when an external factor that disturbs the control in the transient state occurs. It becomes possible.

[Fifth Embodiment]
FIG. 11 is a conceptual diagram showing an example of a partial configuration 500 of the cooling gas temperature control device according to the fifth embodiment.

  This partial configuration 500 is applied as a part of FIG. 1, FIG. 4, FIG. 6, and FIG. 8, and instead of a single temperature measuring device 9, a plurality of temperature measuring devices 9 (example of FIG. 11). Then, four (9 (# 1) to (# 4)) are provided, and immediately after that, the maximum value detector 51 is provided. Then, the maximum temperature detected by the maximum value detector 51 is sent to the PID calculator 12 and the determination modules 20, 30, and 40 shown in FIGS. 1, 4, 6, and 8. Yes.

  Since the configurations of the PID computing unit 12, the adder 13, and the determination modules 20, 30, and 40 are the same as those in FIGS. 1, 4, 6, and 8, here, the plurality of temperature measuring devices 9 and the maximum The value detector 51 will be described, and illustration and duplication description will be avoided for other parts not shown.

  That is, in this embodiment, a plurality of temperature measuring devices 9 are provided. In the example shown in FIG. 11, at each of the outlets of the hydrogen gas coolers 4, 5, 6 and 7, that is, a total of four temperature measuring devices 9 (# 1), 9 (# 2), 9 (# 3) , 9 (# 4).

  The reason for providing a plurality of temperature measuring devices 9 in this way is as follows.

  That is, for example, since there is no backup in the control based on the temperature measured by one temperature measuring device 9 installed only at one representative point, it is difficult to continue the control when this temperature measuring device 9 fails. It becomes.

  The temperature of the hydrogen gas 3 is slightly different at the outlets of the hydrogen gas coolers 4, 5, 6, and 7. Therefore, even if the control is performed only with the representative point temperature (for example, the temperature at the outlet of the hydrogen gas cooler 4), the temperature at any of the outlets of the other hydrogen gas coolers 5, 6, and 7 has a set value. If it exceeds the limit, it may be difficult to determine whether the allowable value up to the alarm point is sufficient.

  Therefore, in the present embodiment, temperature measuring devices 9 (# 1), 9 (# 2), 9 (# 3), and 9 (# 4) are provided at the outlets of the hydrogen gas coolers 4, 5, 6, and 7, respectively. Install each. The maximum value detector 51 selects the highest temperature among the temperatures measured by these four temperature measuring devices 9 (# 1), 9 (# 2), 9 (# 3), 9 (# 4). Then, the selected maximum temperature is provided to the PID calculator 12 and the determination modules 20, 30, and 40.

  As a result, the PID calculator 12 and the determination modules 20, 30, 40 were measured by the plurality of temperature measuring devices 9 (# 1), 9 (# 2), 9 (# 3), 9 (# 4). The highest temperature among the temperatures is used as the current value of the temperature of the hydrogen gas 3.

  As described above, the maximum temperature among the temperatures measured by the plurality of temperature measuring devices 9 (# 1), 9 (# 2), 9 (# 3), and 9 (# 4) is the current temperature of the hydrogen gas 3. By using it as a value, the temperature of the hydrogen gas 3 at the outlet of each hydrogen gas cooler 4, 5, 6 and 7 is controlled below the set value, and an allowable value up to the alarm point can be secured. It becomes possible.

  In addition, when any one of the temperature measuring devices 9 (# 1), 9 (# 2), 9 (# 3), 9 (# 4) becomes unusable due to a failure or trouble, etc. However, the control can be continued.

  Generally, the location where the temperature of the hydrogen gas 3 at the outlet of each of the hydrogen gas coolers 4, 5, 6 and 7 is the highest from the start t1 of the generator 2 until the stable state t3 is reached differs depending on the operating state. When the turbine speed is increased, the temperature of the hydrogen gas 3 at the outlet of the hydrogen gas cooler 4 is the highest, and when the load is increased, the temperature of the hydrogen gas 3 at the outlet of the hydrogen gas cooler 7 may be the highest. .

Therefore, it is possible to perform more reliable and safe control by controlling the temperature of the hydrogen gas 3 at the outlets of the hydrogen gas coolers 4, 5, 6 and 7 as in the present embodiment. Become.
[Sixth Embodiment]
FIG. 12 is a conceptual diagram showing an example of a partial configuration 600 of the cooling gas temperature control device according to the sixth embodiment.

  This partial configuration 600 is a modification of the partial configuration 500 shown in FIG. 11, and includes a plurality of temperature measuring devices 9 (in the example of FIG. 12, 9 (# 1) to (# 4)) as shown in FIG. 4) and the maximum value detector 51, a failure determination unit 53 is also provided.

  Therefore, only the points different from the fifth embodiment will be described here, and illustration and duplication description will be avoided for other parts not shown.

  That is, in this embodiment, a plurality of temperature measuring devices 9 are provided. In the example shown in FIG. 12, similarly to the example shown in FIG. 11, at each of the outlets of the hydrogen gas coolers 4, 5, 6 and 7, that is, a total of four temperature measuring devices 9 (# 1), 9 ( # 2), 9 (# 3), 9 (# 4) are installed.

  The reason for providing the plurality of temperature measuring devices 9 in this way is as described in the fifth embodiment.

  Each of these temperature measuring devices 9 (# 1), 9 (# 2), 9 (# 3), 9 (# 4) measures the temperature of the hydrogen gas 3 and outputs a signal indicating the measured temperature to the maximum value detector. 51 and failure determiner 53.

  The failure determiner 53 is based on the signals from the temperature measuring devices 9 (# 1), 9 (# 2), 9 (# 3), 9 (# 4), and the temperature measuring devices 9 (# 1), 9 ( It is determined whether a failure has occurred in any of # 2), 9 (# 3), and 9 (# 4).

  Specifically, it is determined that the temperature measuring device 9 showing a temperature exceeding a preset alarm temperature is broken. For example, when the set value of the temperature of the hydrogen gas 3 is 45 ° C., the alarm temperature is set to 47 ° C. These are only examples, and the set value and the alarm temperature may be appropriately determined from the temperature at which the insulation resistance in the generator 2 can be safely operated without lowering, or the standard of the “synchronous machine”.

  The failure determination device 53 receives a signal indicating a temperature exceeding the alarm temperature from any one of the temperature measuring devices 9 (# 1), 9 (# 2), 9 (# 3), and 9 (# 4). In the case of failure, it is determined that a failure has occurred in the temperature measuring device 9 that is the output source of this signal, and an alarm is issued together with the notification of the temperature measuring device 9 that has been determined to have failed. Further, the temperature detector 9 determined to have failed is notified to the maximum value detector 51.

  The maximum value detector 51 selects and selects the highest temperature among the temperatures measured by the temperature measuring devices 9 (# 1), 9 (# 2), 9 (# 3), and 9 (# 4). The maximum temperature is provided to the PID calculator 12 and the decision modules 20, 30, 40. In addition, when there is a notification from the failure determination device 53 of the temperature measurement device 9 determined that a failure has occurred, the temperature measured by the notified temperature measurement device 9 is excluded and the highest temperature is selected. To do.

  As a result, the PID calculator 12 and the determination modules 20, 30, 40 were measured by the plurality of temperature measuring devices 9 (# 1), 9 (# 2), 9 (# 3), 9 (# 4). Among the temperatures, the highest temperature excluding the temperature measured by the failed temperature measuring device 9 is used as the current value of the temperature of the hydrogen gas 3.

  With this configuration, according to the present embodiment, the following advantages can be achieved compared to the fifth embodiment.

  For example, when the control is performed by a plurality of (here, four) temperature measuring devices 9 as in the present embodiment or the fifth embodiment, four temperature measuring devices 9 (# 1), 9 (# 2), 9 (# 3), 9 (# 4), for example, the temperature measuring instrument 9 (# 1) has an indication failure in a range that does not cause an instrument failure, and indicates, for example, 50 ° C. or 60 ° C. Assume a case.

  In this case, the other three temperature measuring devices 9 (# 2), 9 (# 3), 9 (# 4) indicate the set value of 45 ° C., and the generator 2 is actually in a stable state. Even in this case, in the fifth embodiment, the control is performed using the maximum temperature, so that the control valve 8 operates in the opening direction and is controlled to lower the temperature of the hydrogen gas 3. End up. As a result, the temperature of the hydrogen gas 3 deviates from the set value of 45 degrees, making it difficult to maintain the set value.

  Actually, the reason why the temperature of the hydrogen gas 3 becomes extremely high, such as 50 ° C. or 60 ° C., is likely due to tube leak in the cooling water system, blockage due to foreign matter contamination, defective temperature measuring instrument, etc. The possibility of relying on control abnormality is low.

  Therefore, as in this embodiment, the PID computing unit 12 and the determination modules 20, 30, and 40 include a plurality of temperature measuring devices 9 (# 1), 9 (# 2), 9 (# 3), and 9 (# 4 ) Is used as the current value of the temperature of the hydrogen gas 3 except for the temperature measured by the failed temperature measuring instrument 9 (# 1). Control can be continued even when there is a leak, blockage due to contamination, or a failure of the temperature measuring device.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are also included in the invention described in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 1 Cooling water, 2 Generator, 3 Hydrogen gas, 4, 5, 6, 7 Hydrogen gas cooler, 8 Control valve, 9 Temperature measuring device, 10 Speed measuring device, 11 Temperature measuring device, 12 PID computing device, 13 Adder, 14, 15, 23 High comparator, 16 Logical operation unit (OR), 17, 17 'Bumpless transfer, 18, 19 Lower limit valve opening setting device, 20, 30, 40 Decision module, 21 Primary delay device , 22, 42 Deviation calculator, 41 Set value setter, 43 Function generator, 51 Maximum value detector, 53 Failure determiner, 100, 200, 300, 400 Cooling gas temperature control device, 500, 600 Partial configuration

Claims (8)

A device for controlling the temperature of the cooling gas for cooling the generator from the start-up of the generator until it reaches a stable state,
A determining means for determining a lower limit value of a valve opening of a control valve for adjusting a flow rate of cooling water for cooling the cooling gas according to a process condition in the generator;
PID calculation means for performing a PID calculation based on a difference between a current value of the temperature of the cooling gas and a preset value related to the temperature of the cooling gas, and determining an adjustment amount of the valve opening;
The valve opening degree is controlled by adding the adjustment amount determined by the PID calculating means to the lower limit value of the valve opening degree determined by the determining means, and applying the addition result to the adjustment valve as an operation amount. Valve opening degree control means,
A cooling gas temperature control device comprising:   The determination means determines the lower limit value of the valve opening by selecting one of two predetermined values as the lower limit value of the valve opening according to the process conditions in the generator. The cooling gas temperature control device according to claim 1.   The determination means, as the process condition, when the rotational speed of the turbine of the generator is equal to or higher than a predetermined rotational speed, or the temperature of the cooling gas is equal to or higher than a predetermined temperature. The cooling gas temperature control device according to claim 1 or 2, wherein the lower limit value of the valve opening is determined so that the lower limit value of the valve opening is higher than a current value. A device for controlling the temperature of the cooling gas for cooling the generator from the start-up of the generator until it reaches a stable state,
When the temperature increase rate of the cooling gas is higher than a predetermined temperature increase rate, the lower limit value of the valve opening of the control valve for adjusting the flow rate of the cooling water for cooling the cooling gas is set from the current value. And a determination means for determining so as to be higher,
PID calculation means for performing a PID calculation based on a difference between a current value of the temperature of the cooling gas and a preset value related to the temperature of the cooling gas, and determining an adjustment amount of the valve opening;
The valve opening degree is controlled by adding the adjustment amount determined by the PID calculating means to the lower limit value of the valve opening degree determined by the determining means, and applying the addition result to the adjustment valve as an operation amount. Valve opening degree control means,
A cooling gas temperature control device comprising: When the lower limit value of the valve opening is determined to be higher than the current value, the determining means determines the lower limit value of the valve opening from the current value to the increased valve opening. To notify the valve opening control means of the rate for changing to
The cooling gas temperature control device according to claim 3 or 4, wherein the valve opening degree control means applies the manipulated variable to the control valve according to the rate.   The determination means determines a lower limit value of the valve opening according to a function set according to a difference between a temperature of the cooling gas and a set value set in advance with respect to the temperature of the cooling gas. 6. The cooling gas temperature control device according to any one of 1 to 5. A plurality of temperature measuring means for measuring the temperature of the cooling gas and providing the measurement result to the PID calculating means;
The said PID calculating means and a determination means use the measurement result which shows the highest temperature among the measurement results provided from these several temperature measurement means as a present value of the temperature of the said cooling gas. The cooling gas temperature control apparatus of any one of these. When any one of the plurality of temperature measuring means fails, it further comprises a failure detecting means for detecting the failed temperature measuring means and issuing an alarm for notifying the failure,
The cooling according to claim 7, wherein the PID calculating means and the determining means do not use the measurement result from the failed temperature measuring means detected by the failure detecting means as the current value of the temperature of the cooling gas. Gas temperature control device.

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