JP5632041B1 - Power plant - Google Patents

Abstract

[PROBLEMS] To reduce the time required for seawater drawn from a water intake to reach the water outlet via a condenser even if the water intake temperature suddenly drops and the temperature difference between the water intake and discharge does not exceed the regulation value. Provided is a power plant capable of performing output control of a power generation unit in consideration. A power generation section that generates power by a steam turbine, a condenser, a seawater system section that feeds the taken seawater to the condenser and drains it into the sea, a case where the intake temperature drops, and When the intake / drain temperature difference is predicted to be outside the regulation value, the controller includes a control unit that controls the output of the power generation unit so that the intake / drain temperature difference falls within the regulation value during the required time. [Selection] Figure 4

Description

  The present invention provides a power generation unit that generates electric power with a steam turbine, a condenser that condenses steam generated by the steam turbine, and seawater taken from a water intake facing the sea to the condenser. Then, the seawater system that drains from the outlet to the sea and the seawater temperature at the intake (hereinafter referred to as “intake temperature”) drop rapidly, and the temperature of the seawater at the outlet (hereinafter referred to as “drainage temperature”). And a control unit that controls the output of the power generation unit when the difference (hereinafter referred to as “intake / drain temperature difference”) is likely to be outside the environmental regulation value (hereinafter sometimes simply referred to as “regulation value”). Related to the power plant.

  In general, in a power plant including a power generation unit that generates power with a steam turbine, steam that has been operated by operating the steam turbine is once returned to water by a condenser. The condenser uses seawater taken from the water intake opening facing the sea as cooling water that returns the steam to the water. (So-called warm waste water).

  In order to drain the seawater whose temperature has risen in this way, for example, in a pollution prevention agreement concluded with a certain local government, the intake / drain temperature difference is determined to be 7 ° C. or less daily and 10 ° C. or less instantaneously.

  For this reason, the power generation plant which controls the output of a power generation part conventionally is developed so that the intake and drainage temperature difference may be settled in the environmental regulation value mentioned above (daily average 7 degrees C or less, instantaneous 10 degrees C or less). For example, paying attention to the correlation between intake / drain temperature difference and output of power generation unit, when the intake / drain temperature difference is 7 ° C or less and the temperature difference at the time of measurement tends to be lower than the previous measurement, The output value of the power generation unit is set to a value higher than the current value, and the output value of the power generation unit is maintained as it is when it does not tend to be lower. In addition, when the temperature difference between intake and drainage is 7 ° C or more and the temperature difference at the time of measurement tends to be higher than at the time of previous measurement, the output of the power generation unit is set to a lower value than the current value and does not tend to increase What is sometimes known to maintain the current situation is known (see Patent Document 1).

JP 2010-248171 A

  However, the power generation plant of the above publication assumes a case where the intake temperature is stable and restricts the output of the power generation unit mainly at an average daily temperature of 7 ° C. or less, so the intake temperature has dropped rapidly. The case is not assumed. More specifically, for example, in winter (November to February), the intake water temperature rapidly decreases (2 to 3 ° C.) due to conditions such as wind speed, temperature, and wave height, and the temperature difference between intake and discharge water is greatly increased. In the case of expansion, the power plant described in the above publication cannot cope.

  In addition, the power plant described in the above publication uses a difference in intake water temperature calculated in real time from the difference between the intake water temperature and the discharge water temperature at the time of measuring the intake water temperature, so that the seawater taken from the intake port is recovered. The time required to reach the drain through the water tank (for example, about 18 minutes at a certain power plant) is not considered. When the seawater reaches the drain, it is necessary to control the output of the power generation unit so that the temperature difference between intake and drainage falls within the regulation value. Such a countermeasure is not provided in the power plant described in the publication.

  Therefore, in view of the above problems, the present invention prevents the difference in intake and discharge temperatures from exceeding the regulation value even when the intake temperature is drastically lowered, and the seawater taken from the intake port passes through the condenser to the discharge port. An object of the present invention is to provide a power plant capable of controlling the output of the power generation unit in consideration of the time required to reach the power.

A power plant according to the present invention includes a power generation unit that generates electric power with a steam turbine, a condenser that condenses steam generated by the steam turbine, and seawater taken from a water intake facing the sea. It is predicted that the difference between the intake water temperature, which is the difference between the intake water temperature and the waste water temperature, will be out of the regulation value when the intake water temperature drops and the seawater system part that sends water to the water device and drains it from the drain outlet In this case, the control unit lowers the output of the power generation unit so that the temperature difference between the intake and drainage falls within a regulation value until the seawater reaches the drainage port from the intake through the condenser. The control unit includes intake temperature, drainage temperature, intake / exhaust temperature difference, which is the difference between the intake and drainage temperatures, a measurement unit that measures condenser inlet temperature, and the intake / exhaust temperature difference is a regulated value. The target intake / drain temperature difference to allow within, the seawater is the intake The input time for the seawater arrival time required to reach the drainage outlet through the condenser and the time required for the start of drainage temperature drop from the start of power generation unit output control to the start of drainage temperature drop are set by the operator. An input setting unit, and a calculation setting unit for setting a target drainage temperature by calculation based on a reduced intake water temperature and the target intake / drain temperature difference are provided .

According to this configuration, since the control of lowering the output of the power generation unit is performed so that the difference in intake and discharge temperatures is within the regulation value until the seawater reaches the drain, the intake temperature is decreased. In addition, the temperature difference between intake and drainage is prevented from being outside the regulation value. Further, the target drainage temperature is easily and accurately obtained.

  Further, as another aspect of the power plant according to the present invention, the control unit is configured to calculate a condenser inlet temperature derived from accumulated data and a drain temperature when the power generation unit is operating at a high output. Second point of the point coordinates of the current condenser inlet temperature in the correlation of 1, the condenser inlet temperature derived from the accumulated data, and the drainage temperature when the power generation unit is operating at a low output A reference graph is created by connecting point coordinates of the current condenser inlet temperature in the correlation, and the target power generation unit output is obtained from the reference graph based on the target drainage temperature set by the calculation setting unit. A configuration can also be adopted.

  In this case, the target power generation unit output is easily and accurately obtained.

  Further, the control unit corrects the point coordinates in the first correlation based on the current drain temperature and the output of the power generation unit in the reference graph, and the corrected point coordinates and the first It is also possible to create a correction graph by connecting the point coordinates in the correlation of 2 and obtain the target power generation unit output from the correction graph based on the target drain temperature set by the calculation setting unit. it can.

  In this case, the target power generation unit output is easily and more accurately obtained.

  Further, as another aspect of the power plant according to the present invention, the control unit is required to reach the target power generation unit output reaching time until the power generation unit output at the time when the reduced intake temperature is measured falls to the target power generation unit output. Based on the target drain temperature reaching time required for the drain temperature when the reduced intake water temperature is measured to drop to the target drain temperature, the drain temperature drop starting required time, and the sea water reaching time It is also possible to employ a configuration including a time calculation unit that calculates the required time for starting the power generation unit output control required from the time when the reduced intake water temperature is measured to the time when the output control of the power generation unit is started.

  In this case, the required time for reaching the target power generation unit output, the required time for reaching the target drainage temperature, and the required time for starting the power generation unit output control are easily and accurately obtained.

  Further, as another aspect of the power plant according to the present invention, the control unit determines whether or not the target intake / drain temperature difference is within a set value within the time required for starting the power generation unit output control, and the target intake / drainage. When the temperature difference is within the set value, it is possible to adopt a configuration in which the output drop control of the power generation unit is stopped.

  In this case, it is determined whether or not the target intake / drain temperature difference is within the set value within the time required for starting the power generation unit output control, and even if the target intake / drain temperature difference is instantaneously outside the set value, If the target intake / drain temperature difference is within the set value within the time required for starting the part output control, the output drop control of the power generation part is not performed. That is, the output drop control of the power generation unit with high accuracy suitable for the environment is performed.

Further, as another aspect of the power plant according to the present invention, the control unit controls the output to fall at a fixed value when the output of the power generation unit is a predetermined value or more within the target power generation unit output arrival time, If the output of the power generation unit is lower than the plant value, it is also possible to use a construction such that the control to output drops at set value is automatically set.

  In this case, the output of the power generation unit can be accurately lowered without causing any trouble to the power generation unit.

  Further, as another aspect of the power plant according to the present invention, the control unit includes: reference data composed of an output of the power generation unit, intake / drain temperature difference, condenser inlet temperature, drainage temperature, target power generation unit output, target It is also possible to employ a configuration that includes a display unit that displays operation target data configured by a difference in intake and discharge temperatures and a target drainage temperature.

  In this case, the operator can grasp the current state of the power plant from the reference data, and can grasp the control contents of the power generation unit output and the drainage temperature from the operation target data.

  According to the present invention, even when the seawater temperature is lowered, the time required for the seawater taken from the intake port to reach the drainage port via the condenser, so that the temperature difference between the intake and drainage does not exceed the regulation value. It is possible to perform output control of the power generation unit in consideration of (delay time).

1 is a schematic configuration diagram of a power plant according to an embodiment of the present invention. The block diagram which shows the structure of the hardware of the control part of the power plant which concerns on the embodiment. The functional block diagram which shows the function of the control part of the power plant concerning the embodiment. It is a figure which shows the control content of the power plant which concerns on the embodiment, and drainage temperature falls by the output fall control of a power generation part until seawater reaches a drainage port from a water intake through a condenser. The figure which shows the state where the intake / drain temperature difference is settled in a regulation value. (A) is a figure which shows the reference | standard graph produced in the control part of the power plant which concerns on the same embodiment, (b) is a figure which shows the correction | amendment graph created by the control part of the power plant which concerns on the same embodiment. The figure which shows the display part of the power plant which concerns on the embodiment. The figure which shows the control flow of the 1st step performed in the control part of the power plant concerning the embodiment. The figure which shows the control flow of the 2nd step performed in the control part of the power plant which concerns on the embodiment. The figure which shows the control flow of the 3rd step performed in the control part of the power plant which concerns on the embodiment.

  A power plant according to an embodiment of the present invention will be described with reference to FIGS. 1 to 9A and 9B. As shown in FIG. 1, the power plant 1 according to the present embodiment includes a power generation unit 2, a condenser 3, a seawater system unit 4, and a control unit 5.

  The power generation unit 2 generates predetermined power by a steam turbine (not shown).

  The condenser 3 condenses the steam generated by the steam turbine.

  The seawater system section 4 includes an inlet-side flow path 4 a connected from the intake port 40 to the inlet of the condenser 3, and an outlet-side flow path 4 b connected from the outlet of the condenser 3 to the drain port 41. Yes. Then, the seawater taken from the water intake port 40 is fed to the condenser 3 by the inlet side channel 4a, and the water is fed from the condenser 3 to the drain port 41 by the outlet side channel 4b.

  The inlet-side flow path 4a includes a condenser inlet valve 42 and a condenser inlet temperature sensor T1 that measures the temperature of seawater at the inlet of the condenser 3 (hereinafter referred to as “condenser inlet temperature”). Is provided. The condenser outlet side channel 4b has a condenser outlet valve 43 and a condenser outlet for measuring the temperature of seawater at the outlet of the condenser 3 (hereinafter referred to as “condenser outlet temperature”). A temperature sensor T2 is provided.

  Further, the intake port 40 is provided with an intake temperature sensor T3 for measuring the temperature of the seawater (intake temperature) at the intake port 40. Further, the drain port 41 is provided with a drain port temperature sensor T4 that measures the temperature of the seawater (drain temperature) at the drain port 41. The condenser inlet temperature sensor T1, the condenser outlet temperature sensor T2, the intake port temperature sensor T3, and the drain temperature sensor T4 are connected to the control unit 5, and the measured temperature data is transmitted to the control unit 5. It has come to be.

  As shown in FIG. 2, the control unit 5 includes a CPU (Central Processing Unit) 50, an internal memory 51, an operation unit 52, a display unit 53, an I / O controller 54, a device connection interface 55, and a communication I / F 58. The lines 56 are connected to each other.

  The CPU 50 implements necessary control by appropriately reading and executing various programs stored in the internal memory 51. The internal memory 51 stores a program that is read and executed as appropriate, and stores various types of information created by executing the program.

  The operation unit 52 includes a keyboard and operation buttons for performing various settings and input operations, and input information from the operation unit 52 is processed under the control of the CPU 50. That is, the operator can perform various necessary setting operations or designation operations via the operation unit 52.

  An external storage unit 57 composed of a hard disk or the like can be connected to the I / O controller 54. The external storage unit 57 stores a program for the control unit 5. Further, the external storage unit 57 stores temperature data from various temperature sensors T1 to T4, an output value of the power generation unit 2, a set value input by the operation unit 52, a set value to be calculated, and the like.

  The device connection interface 55 is an interface for connecting the control unit 5 and various temperature sensors T1 to T4 so that temperature data measured by the various temperature sensors T1 to T4 can be received.

  The communication I / F 58 is a network adapter that enables the control unit 5 to be connected to another server (not shown) or the like via a dedicated network or a public network.

  And the control part 5 is when the intake water temperature falls rapidly, and when the difference (intake water temperature difference) between intake water temperature and drainage temperature is estimated to become outside a regulation value, seawater is the intake 40 The output of the power generation unit 2 is configured to fall so that the temperature difference between intake and drainage falls within the regulation value before reaching the drain 41 through the condenser 3. Specifically, as shown in FIG. 3, the control unit 5 includes a measurement unit 500, an input setting unit 501, a calculation setting unit 502, a time calculation unit 503, a first time distribution setting unit 504, A second time distribution setting unit 505.

  The measuring unit 500 acquires each temperature data of the condenser inlet temperature, the condenser outlet temperature, the intake water temperature, and the drainage temperature. More specifically, the measuring unit 500 acquires the condenser inlet temperature temperature data from the condenser inlet temperature sensor T1, and acquires the condenser outlet temperature temperature data from the condenser outlet temperature sensor T2. The temperature data of the intake water temperature is acquired from the intake water temperature sensor T3, and the temperature data of the water discharge temperature is acquired from the water discharge temperature sensor T4.

  The input setting unit 501 is a target intake / drain temperature difference for allowing the intake / drain temperature difference to be within the regulation value, and a seawater arrival time required for the seawater to reach the drainage port 41 from the intake port 40 through the condenser 3. t0, a drainage temperature drop start required time t3 required from the output control start point of the power generation unit 2 to the start point of the drainage temperature drop is set by an input by the operator using the keyboard of the operation unit 52 or the like.

  The calculation setting unit 502 includes a difference between the intake water temperature measured by the intake water temperature sensor T3 and the waste water temperature measured by the water outlet temperature sensor T4, and the intake water temperature that has been rapidly reduced. The target drainage temperature is calculated and set from the target intake / drainage temperature difference.

  As shown in FIG. 4, the time calculation unit 503 requires a target power generation unit output arrival time required until the output of the power generation unit 2 at the time when the intake water temperature that has rapidly dropped is measured decreases to a target power generation unit output described later. t1 and a target drainage temperature required time t2 required until the drainage temperature at the time when the intake water temperature that has rapidly dropped is measured falls to the target drainage temperature, and these and the seawater arrival required time t0 and Based on the drain temperature drop start required time t3, the power generation unit output control start required time t4 required from the time when the intake water temperature rapidly decreased is measured to the control start time of the power generation unit output is calculated.

  As shown in FIG. 4, the first time distribution setting unit 504 sets the power generation unit output control start required time t4, the drainage temperature drop start required time t3, and the target drainage temperature arrival required time t2 to the seawater arrival required time. Allocate time so that it is within t0.

  As shown in FIG. 4, the second time distribution setting unit 505 sets the power generation unit output control start required time t4 and the target power generation unit output arrival required time t1 from the seawater arrival required time t0 to the drainage temperature drop start required. The time is distributed so as to be within the time obtained by subtracting the time t3.

  Therefore, the first time distribution setting unit 504 distributes the power generation unit output control required time t4, the drainage temperature drop start required time t3, and the target drainage temperature arrival required time t2 so as to be within the seawater arrival required time t0. Therefore, the drain temperature drop control can be completed within the seawater arrival time t0. The second time distribution setting unit 505 allows the power generation unit output control start required time t4 and the target power generation unit output arrival required time t1 to fall within the time obtained by subtracting the drainage temperature drop start required time t3 from the seawater arrival required time t0. Thus, the power generation unit output drop control can be completed within the seawater arrival time t0.

  Further, the control unit 5 determines whether or not the target intake water temperature difference is within the set value within the power generation unit output control start required time t4 by the control flow S3 shown in FIG. By this determination, when the target intake / drain temperature difference is within the set value, the power generation unit output drop control is stopped. That is, if the target intake / drain temperature difference falls within the set value within the time required for starting the power generation unit output control t4, the output drop control of the power generation unit 2 is not performed. That is, the output drop control of the power generation unit 2 with high accuracy suitable for the environment is performed.

  Further, as shown in FIG. 4, the control unit 5 has a fixed value (for example, at a time t10 when the output of the power generation unit 2 is equal to or greater than a predetermined value (for example, 310 MW) within the target power generation unit output arrival time t1. 3 MW / min), the output is controlled to drop, and is automatically set by the AFC (device for automatically controlling the target frequency of the entire system) at time t11 when the output of the power generation unit 2 is lower than the predetermined value. Control is performed so that the output drops at a set value (for example, 8 MW / min). By controlling in this way, the output of the power generation unit 2 is accurately lowered to the target value without causing any trouble to the power generation unit 2.

  Here, the relationship between the intake / drain temperature difference and the output of the power generation unit 2 will be described. The temperature difference between intake and drainage has a certain relationship with the output of the power generation unit 2. For example, the increase or decrease of the output of the power generation unit 2 is related to the increase or decrease of the steam flowing into the steam turbine, and is related to the increase or decrease of the steam cooled by the condenser 3. Moreover, the increase / decrease in the steam cooled by the condenser 3 is related to the increase / decrease in the amount of heat exchange with the seawater, and is related to the level of the temperature difference between the intake and drainage. In the present embodiment, the condenser inlet temperature is stable regardless of changes in the intake water temperature, and therefore the condenser inlet temperature is used as a parameter when creating a graph.

  Furthermore, as shown in FIG. 3, the control unit 5 stores the intake water temperature, the drainage temperature, the condenser inlet temperature, and the condenser outlet temperature that are correlated with the output of the power generation unit 2. . That is, the control unit 5 includes a first temperature database 506 as first temperature storage means and a second temperature database 507 as second temperature storage means.

  The first temperature database 506 includes intake water temperature, drainage temperature, condenser inlet temperature, and condenser outlet temperature measured when the power generation unit 2 is operating at a low output (for example, 175 MW). It is stored and accumulated periodically in association.

  The second temperature database 507 includes the intake water temperature, drainage temperature, condenser inlet temperature, and condenser outlet temperature measured when the power generation unit 2 is operating at a high output (for example, 310 MW). It is stored and accumulated periodically in association.

  Then, as shown in FIG. 3, the control unit 5 includes a reference graph creation unit 508 that creates the reference graph A of the output of the power generation unit 2 based on the above-described correlation and the temperature-related database, and the current drainage A correction graph creation unit that corrects the reference graph A based on the temperature and the output of the power generation unit 2 and creates a correction graph B for obtaining the target power generation unit output based on the target drainage temperature set by the input setting unit 501 509.

  As shown in FIG. 5A, the reference graph A is derived from the accumulated data, and the condenser inlet temperature and the power generation unit 2 are operating at a high output (310 MW in this embodiment). Of the current condenser inlet temperature in the correlation with the waste water temperature (first correlation) and the condenser inlet temperature derived from the accumulated data, and the power generation unit 2 has a low output ( In this embodiment, it is created by connecting point coordinates of the current condenser inlet temperature in the correlation (second correlation) with the drainage temperature when operating at 175 MW).

  As shown in FIG. 5B, the correction graph B corrects the point coordinates in the first correlation based on the current drain temperature and the output of the power generation unit 2 in the reference graph A, and the correction. It is created by connecting the point coordinates thus obtained and the point coordinates in the second correlation.

  Moreover, the control part 5 is provided with the display part 53 on which the temperature measured by the measurement part 500, the temperature data controlled by the control part 5, power generation part output data, etc. are displayed as mentioned above. The display unit 53 displays reference data and operation target data as shown in FIG. The reference data includes the output of the power generation unit 2, intake / drain temperature difference, intake water temperature, condenser inlet temperature, drainage temperature, and time required to reach seawater. Operational target data includes target power generation unit output, target intake / drain temperature difference, reduced intake water temperature, load (power generation unit output) change rate, target power generation output arrival time, target drainage temperature, and power generation unit output control start time. Composed. By displaying the reference data and the operation target data on the display unit 53, the operator can grasp the current state of the power plant 1 based on the reference data, and the output of the power generation unit 2 and the operation target data based on the operation target data. The control contents of the drainage temperature can be grasped.

  Next, output control of the power generation unit 2 in the control unit 5 will be described with reference to FIGS. In the present embodiment, the case where the intake water temperature is drastically lowered by 2 to 3 ° C. by the intake water temperature sensor T3 in the winter will be described as an example. Further, in the control unit 5, from the first temperature database 506, various temperature sensors (condenser inlet temperature sensor T1, condenser outlet temperature sensor T2, when the output of the power generation unit 2 is high output (for example, 310 MW), Measurement temperature data by the intake temperature sensor T3 and the drain temperature sensor T4) is acquired, and various temperature sensors T1 to T4 when the output of the power generation unit 2 is low (for example, 175 MW) from the second temperature database 507. It is assumed that measured temperature data is acquired. In the internal memory 51, it is assumed that these temperature data are stored in association with the output of the power generation unit 2.

  First, the control flow in the control unit 5 will be described. The control flow is composed of a control flow of a first stage to a third stage.

  As shown in FIG. 7, the first-stage control flow S <b> 1 includes a step S <b> 10 for detecting that the intake water temperature has rapidly dropped, a step S <b> 11 for issuing an alarm to the operator based on the detection signal, Steps S12 and S13 in which the operator switches from the normal operation to the output drop control operation by the alarm are performed.

  As shown in FIG. 8, the control flow S2 in the second stage includes a target power generation unit based on the step S20 for creating the reference graph A, the step S21 for creating the correction graph B, and the reference graph A and the correction graph B. Step S22 for obtaining an output.

  As shown in FIG. 9, the control flow S3 in the third stage is measured in step S30 for starting output drop control of the power generation unit 2, and in step S31 in which the reference data and the operation target data are displayed on the display unit. Step S33 in which the intake water temperature is displayed, Step S34 in which the target drainage temperature is calculated, Step S35 in which the target power generation unit output and the target drainage temperature are displayed on the display unit, and Steps S36 and S37 in which time distribution is performed. , S38, step S39 for determining the target drainage temperature difference, and step S390 in which the output drop control of the power generation unit 2 is stopped.

  Hereinafter, description will be given according to the control flow S1 to S3 of the first stage to the third stage. First, in the control flow S1 of the first stage, when the intake temperature sensor T3 detects that the intake temperature has dropped abruptly by 2 to 3 ° C. (step S10), to the operator by voice or light, An alarm for performing output drop control of the power generation unit 2 is transmitted (step S11).

  Then, the operator who has received the warning selects the power generation unit output lowering control mode in the operation unit 52 (step S12). By this operation, the normal operation is switched to the power generation unit output lowering control operation (step S13).

  Next, the process proceeds to the second-stage control flow S2. As shown in FIG. 5A, the point coordinate of the current condenser inlet temperature in the first correlation is connected to the point coordinate of the current condenser inlet temperature in the second correlation. A reference graph A is created (step S20).

  Next, as shown in FIG. 5B, in the created reference graph A, the point coordinates in the first correlation are corrected based on the current drainage temperature and the output of the power generation unit 2, and the correction is performed. The corrected graph B is created by connecting the point coordinates thus obtained and the point coordinates in the second correlation (step S21). Then, in the correction graph B, the target power generation unit output is obtained based on the target drain temperature “17.5 ° C.” (step S22).

  Next, when the control flow S3 of the third stage, that is, the output drop control operation of the power generation unit 2 is started (step S30), the output of the power generation unit 2 at this time, the intake / drain temperature difference, the condenser inlet temperature. The reference data configured with the drainage temperature and the operation target data configured with the target power generation unit output, the target intake / drain temperature difference, and the target drainage temperature are displayed on the display unit 53 (step S31). For example, as shown in FIG. 6, “320 MW” is displayed in the power generation unit output display field, “8.4 ° C.” is displayed in the intake water temperature difference display field, and “10” is displayed in the water intake temperature display field. ”Is displayed,“ 11.1 ° C. ”is displayed in the condenser inlet temperature display column, the actual temperature“ 18.4 ° C. ”and the calculated temperature“ 17.7 ° C. ”are displayed in the drain temperature display column. Is displayed. In addition, “18 min” is displayed in the seawater arrival required time display column. On the other hand, “8 ° C.” is displayed as the operation target data in the intake temperature display column of the operation target data. In addition, the display columns of the target power generation unit output, target intake / drain temperature difference, and target drainage temperature of the operation target data are blank.

  The reference data is displayed on the display unit 53 by transmitting the measured temperature data of the various temperature sensors T <b> 1 to T <b> 4 to the control unit 5 through the device connection interface 55 described above. Further, the seawater arrival required time t0 and the drainage temperature drop start required time t3 in the reference data are both determined by the flow path length of the power plant 1, and are input in advance by the operator and stored in the internal memory 51. It shall be. In addition, the target intake / drain temperature difference of the target operation data is input and set by the operator. However, the water intake temperature “8 ° C.” displayed in the water intake temperature display field of the display unit 53 is displayed when it is detected by the water intake temperature sensor T3.

  When the intake water temperature drops by 2 ° C., the operator confirms that the intake water temperature displayed in the operation target data of the display unit 53 is “8 ° C.” (step S32). On the other hand, “Δ9.5 ° C.” is input and set in the target intake / drain temperature difference display field of the target operation data so that the intake / exhaust temperature difference falls within the regulation value with respect to the displayed intake temperature (step S33). . The target intake / drain temperature difference that has been input is displayed in the target intake / drain temperature difference display field of the display unit 53 (see FIG. 6).

  Next, when the target intake / drain temperature difference “Δ9.5 ° C.” of the target operation data is input and set, in the calculation setting unit 502, the intake temperature “8 ° C.” of the operation target data and the target intake / drain temperature difference “Δ9. The target drain temperature “17.5 ° C.” is obtained from “5 ° C.” (step S34). Then, the target power generation unit output “283 MW” corresponding to the target drainage temperature “17.5 ° C.” obtained in the control flow S2 of the second stage is displayed on the display unit 53 as the operation target data as shown in FIG. It is displayed (step S35).

  Next, in the time calculation unit 503, based on the target power generation unit output arrival required time t1, the target drainage temperature arrival required time t2, the drainage temperature drop start required time t3, and the seawater arrival required time t0, the power generation unit output A control start required time t4 is calculated (step S36). Of the calculated required times, only the target power generation unit output arrival required time t1 “6.8 min” and the power generation unit output control start required time t4 “4.1 min” are displayed in the operation target data of the display unit 53. The Further, the target drain temperature reaching required time t2 and the target power generation unit output reaching required time t1 are the same time. Further, a time obtained by adding the target drain temperature arrival required time t2 and the drain temperature drop start required time t3 is the total drain temperature drop required time.

  Next, as shown in FIG. 4, the first time distribution setting unit 504 causes the power generation unit output control start required time t4 “4.1 min”, the drainage temperature drop start required time t3 “7 min”, the target drainage temperature reaching required time. The time distribution is performed so that t2 “6.71 min” falls within the required seawater arrival time t0 “18 min” (step S37).

  On the other hand, as shown in FIG. 4, the second time distribution setting unit 505 determines that the power generation unit output control start required time t4 “4.1 min” and the target power generation unit output arrival required time t1 “6.8 min” are required to reach seawater. The time is distributed so as to be within the time obtained by subtracting the drain temperature drop start required time t3 “7 min” from the time t0 “18 min” (step S38).

  Then, when the power generation unit output control start required time t4 “4.1 min” is time-distributed, is the target intake / drain temperature difference within the set value within the power generation unit output control start required time t4 “4.1 min”? It is determined whether or not (step S39). At this time, if the target intake / drain temperature difference is within the set value, the power generation unit output drop control is stopped (step S390). Then, “stop power generation unit output drop control” is displayed in the display field of the target power generation unit output of the operation target data shown in FIG.

  And based on the reference | standard graph A and the correction | amendment graph B, the output of the electric power generation part 2 is the target electric power generation part output arrival required time t1 (6. 71 minutes), when the power generation unit output is a predetermined value or more (310 MW or more), the output drops for t10 (3.33 minutes) at a fixed value (for example, 3 MW / min), and the output of the power generation unit 2 is When it becomes lower than the predetermined value, the output drops at t11 (3.38 minutes) at a set value (for example, 8 MW / min) set automatically. The set value that is automatically set is displayed in the display column for selecting the load change rate of the operation target data (see FIG. 6).

  On the other hand, the drainage temperature passes through the drainage temperature drop start required time t3 (7 minutes) from the time when the power generation unit output control start required time t4 (4.1 minutes) has elapsed, and then reaches the target drainage temperature arrival required time t2 (6.71). Within a minute), the temperature of the drainage water at the time when the intake water temperature that has rapidly dropped is measured falls to the target wastewater temperature. Specifically, when the output drops at t20 (3.33 minutes) at 0.1 ° C / min and the drainage temperature becomes lower than the predetermined value, t21 (3.38 at 0.14 ° C / min. Descent). Therefore, the temperature difference between the intake water and the intake water is within the regulation value until the seawater reaches the drain port 41 from the intake port 40 through the condenser 3.

  As described above, according to the power plant according to the present invention, power generation is performed so that the temperature difference between the intake water and the intake water is within the regulation value until the seawater reaches the discharge port 41 through the condenser 3 from the intake port 40. Since the control for lowering the output of the unit 2 is performed, it is possible to prevent the difference between the intake and drainage temperatures from being outside the regulation value even if the intake water temperature is suddenly lowered. That is, practical control that can cope with a sudden drop in the intake water temperature is performed in the power plant 1.

  In addition, the power plant concerning this invention can be variously changed without being limited to the said embodiment.

  For example, in the case of the above embodiment, the seawater arrival required time t0 and the drainage temperature drop start required time t3 are both determined by the flow path length, and can be appropriately changed according to the configuration of various power plants.

  Moreover, in the said embodiment, although demonstrated taking the case where the temperature of the water intake 40 fell rapidly 2 degreeC as an example, the power plant of this invention has a structure which can change arbitrarily the temperature numerical value to fall.

  Further, in the case of the above embodiment, when the output drop control of the power generation unit 2 is performed, if the AFC is not used, the change rate of the drainage temperature is normally 0.14 ° C./min×11/8, or In the case of emergency, it is set to 0.14 ° C./min×13/8.

  DESCRIPTION OF SYMBOLS 1 ... Power generation plant, 2 ... Power generation part, 3 ... Condenser, 4 ... Seawater system part, 4a ... Inlet side flow path, 4b ... Outlet side flow path, 5 ... Control part, 40 ... Water intake, 41 ... Drain port 42 ... Condenser inlet valve, 43 ... Condenser outlet valve, 51 ... Internal memory, 52 ... Operation part, 53 ... Display part, 54 ... Controller, 55 ... Interface for equipment connection, 56 ... Bus line, 57 ... External storage unit, 500 ... measurement unit, 501 ... input setting unit, 502 ... calculation setting unit, 503 ... time calculation unit, 504 ... first time distribution setting unit, 505 ... second time distribution setting unit, 506 ... first temperature Database, 507 ... second temperature database, 508 ... reference graph creation unit, 509 ... correction graph creation unit, A ... reference graph, B ... correction graph, T1 ... condenser inlet temperature sensor, T2 ... condenser outlet temperature sensor , T3 ... intake temperature sensor, 4 ... Drain outlet temperature sensor, t0 ... Time required for seawater arrival, t1 ... Time required for target power generation unit output, t2 ... Time required for target drainage temperature arrival, t3 ... Time required for start of drainage temperature drop, t4 ... Time required for starting power generation unit output control time

Claims (7)

A power generation unit that generates electric power with a steam turbine, a condenser that condenses the steam generated by the steam turbine, and seawater taken from a water intake facing the sea is fed to the condenser and drained. When the intake water temperature drops and the intake water temperature difference, which is the difference between the intake water temperature and the waste water temperature, is predicted to be outside the regulation value, the sea water A controller that lowers the output of the power generation unit so that the temperature difference between the intake and drainage falls within a regulation value before reaching the drainage port through the condenser from the intake port ;
The controller is
Measuring section for measuring intake temperature, drainage temperature, intake / drain temperature difference between intake temperature and drainage temperature, condenser inlet temperature,
Target intake / drain temperature difference to allow the intake / drain temperature difference to be within the regulation value, seawater arrival time required for the seawater to reach the drain through the condenser, and output control of the power generation unit An input setting unit in which the drain temperature drop start required time required from the start time to the start point of the drain temperature drop is input and set by the operator,
A power plant comprising: a calculation setting unit for setting a target drainage temperature by calculation from a reduced intake water temperature and the target intake / drain temperature difference . The controller is
Point coordinates of current condenser inlet temperature in the first correlation between condenser inlet temperature derived from accumulated data and drainage temperature when power generation unit is operating at high power, and accumulation Connecting the condenser inlet temperature derived from the measured data and the point coordinates of the current condenser inlet temperature in the second correlation between the drainage temperature when the power generation unit is operating at low power Create a reference graph,
The power plant according to claim 1 , wherein a target power generation unit output is obtained from a reference graph based on a target drainage temperature set by the calculation setting unit. The controller is
In the reference graph, the point coordinates in the first correlation are corrected based on the current drain temperature and the output of the power generation unit, and the corrected point coordinates and the point coordinates in the second correlation are corrected. To create a correction graph,
The power plant according to claim 2 , wherein a target power generation unit output is obtained from a correction graph based on a target drainage temperature set by the calculation setting unit. The controller is
The target power generation unit output arrival time required until the power generation unit output at the time when the reduced intake temperature is measured falls to the target power generation unit output, and the drainage temperature at the time when the reduced intake temperature is measured are the target. The output of the power generation unit from the time when the reduced intake water temperature, which is obtained based on the time required for reaching the target wastewater temperature to fall to the wastewater temperature, the time required for starting the temperature drop and the time required for reaching seawater, is measured. The power plant according to claim 2 or 3 , further comprising a time calculation unit for calculating a time required for starting the power generation unit output control required at a control start time. The control unit determines whether or not the target intake / drain temperature difference is within the set value within the time required for starting the power generation unit output control, and if the target intake / drain temperature difference is within the set value, The power plant according to claim 4 , wherein the output drop control is stopped. Wherein, in the target power generation unit outputs arrival required time, if the output of the power generation unit is a predetermined value or more, and controlled to output drops at a fixed value, the output of the power generation portion is lower than the plant value 6. The power plant according to claim 4 , wherein the power plant is controlled to drop the output at a set value that is automatically set. The control unit is composed of reference data composed of power generation unit output, intake / drain temperature difference, condenser inlet temperature, drainage temperature, target power generation unit output, target intake / temperature difference, target drainage temperature. The power plant according to any one of claims 1 to 6 , further comprising a display unit that displays target data.

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