JPH0744205A - Controller for thermal power plant - Google Patents

Abstract

PURPOSE:To minimize the fluctuation of a main steam temperature at the time of a load command signal change by automatically adjusting the parameter of a dynamic preceding control signal for suppressing the fluctuation of the main steam temperature when changing the load command signal of a thermal power plant. CONSTITUTION:This device is provided with an adjuster 1 for automatically adjusting the parameter for specifying a dynamic preceding control signal FV. The adjuster 1 is provided with a deviation sampling function 2 for time sequentially sampling deviation DELTAT between the real main steam temperature and a set temperature, feature amount extracting function 4 for extracting deviation Tmc at the change end time of the load command signal in the sampled deviation, correction coefficient estimating function 6 for calculating a correction coefficient CpK for correcting a present parameter (gain) K corresponding to the extracted deviation Tmc, and parameter arithmetic function 8 for calculating a new parameter by multiplying this correction coefficient CpK to the present parameter K and for outputting this new parameter to a dynamic preceding control signal generator 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for a thermal power plant equipped with a boiler for generating steam and a steam turbine driven by the steam generated by the boiler, and more particularly to a load for the thermal power plant. The present invention relates to a control device that performs advanced control of a thermal power plant by a static advanced control signal corresponding to a load command signal shown and a dynamic advanced control signal for suppressing fluctuation of the steam when the load command signal changes.

[0002]

2. Description of the Related Art In the field of automatic control of a thermal power plant, feedback control and advance control have been used to suppress fluctuations in main steam temperature, resulting in significant improvements in plant controllability. In particular, advanced control is effective for a thermal power plant with a large response delay. However, conventionally, the plant operator manually adjusts the control parameter that determines the control signal in these control methods while observing the variation in the control amount. For example, the control parameters for determining the dynamic advanced control signal that controls the fuel quantity (the control signal when transitioning from a steady state to another steady state) are empirical for many years based on observation results such as main steam temperature fluctuations. The operators themselves make adjustments based on their knowledge.

Attempts at automatic adjustment of control parameters have been made in feedback control, especially in PI, which accounts for the majority.
Seen in the adjustment of the D controller. For example, JP-A-63
In the technique described in Japanese Patent No. 247801 (hereinafter, Prior Art 1), a response waveform of a control amount (main steam temperature) when a target value (main steam temperature set value) changes or when a disturbance (load command signal) is applied And a control response shape recognizing means for observing the overshoot amount and the damping coefficient, and a control parameter for qualitatively evaluating the overshoot amount and the damping coefficient and estimating a modified value of the PID control parameter by fuzzy inference. The control parameter of the PID controller is automatically adjusted by including the correction means and the controllability determination means that causes the control parameter correction means to function when the overshoot amount and the damping coefficient exceed the allowable range.

On the other hand, regarding the prior control technology in the field of thermal power plant automatic control, for example, Japanese Patent Publication No.
There is one described in Japanese Patent Laid-Open No. 2 (hereinafter, Prior Art 2). This technique is a technique for suppressing fluctuations in main steam pressure, but is a technique similar to the present invention as a prior control technique in the field of thermal power plant automatic control. In the present technology, the main steam pressure is regulated by operating the input amounts such as the feed water amount and the fuel amount of the boiler according to the static advance control signal according to the load command signal of the boiler and the correction signal according to the main steam pressure deviation. When controlling to a value, from the start of the change of the load command signal, the dynamic control signal for the main steam pressure is output in response to the change of the load command signal to correct the static control signal.
Also, set a predetermined time before the change of the load command signal is completed,
At the set time point, the dynamic preceding control signal is directed to shut off or converge. The preceding control method minimizes changes in the main steam pressure when the load changes and when the engine is stopped.

[0005]

According to the prior art 1,
The PID control parameter can be efficiently and automatically adjusted from the control response waveform shape observed when the target value changes or when a disturbance is applied. However, Prior Art 1 does not take into consideration the automatic adjustment of the control parameters when the effective advanced control is also used for a thermal power plant with a large response delay. Also,
According to the related art 2, by performing the preceding control, it is possible to minimize the fluctuation of the main steam pressure when the load command signal changes and when the engine is stopped. However, even in Conventional Technique 2, no consideration is given to adjustment of the advance control parameter.

That is, in any of the conventional techniques,
Regarding the control parameters that determine the advance control signal, the plant operator must make adjustments based on his / her own experience, which is a load on the operator. There is a problem of disappearing.

The present invention has been made by paying attention to such a conventional problem, and when adjusting the dynamic advance control signal, an appropriate optimum dynamic advance control signal is obtained regardless of the experience and intuition of the operator. It is an object of the present invention to provide a control device for a thermal power plant that can create the above, and can suppress the fluctuation of the main steam temperature when the load command signal changes or when the engine is stopped.

[0008]

A control device for a thermal power plant for achieving the above-mentioned object comprises an actual temperature of steam for driving a steam turbine and a preset steam temperature for the temperature of the steam. Of the steam temperature deviation grasping means for grasping the steam temperature deviation and the steam temperature deviation grasped by the steam temperature deviation grasping means, the load command signal indicating the load of the thermal power plant changes, and the time when the change ends In the characteristic deviation extracting means for extracting the steam deviation as a characteristic quantity of the steam temperature change, and in accordance with the steam deviation extracted by the characteristic quantity extracting means, the gain amount of the dynamic preceding control signal is obtained, and the gain is calculated. A parameter calculating means for outputting the quantity to the dynamic preceding control signal generating means as one of the parameters for specifying the dynamic preceding control signal. It is intended.

Here, the parameter calculating means may stop calculating the new gain amount and display the gain amount on the display means. Further, as the feature amount of the steam change, the feature amount extraction means, the maximum steam temperature deviation from the change start time of the load command signal to the change end time, and the maximum after the change end time of the load command signal. It is preferable to extract the steam temperature deviation.
Further, the parameter calculation means may obtain a new parameter from the extracted feature amount by so-called fuzzy inference.

[0010]

The temperature of the steam that drives the steam turbine is measured by a thermometer. The steam temperature deviation between the steam temperature and the set steam temperature is grasped by the steam temperature deviation grasping means.
The characteristic amount extraction means extracts, as the characteristic amount of the steam temperature change, the steam deviation at the change end time of the load command signal from the steam temperature deviation grasped by the steam temperature deviation grasping means. The parameter calculation means obtains the gain amount of the dynamic preceding control signal according to the steam deviation extracted by the feature amount extraction means. This gain amount is output to the dynamic advance control signal generating means as one of the parameters for specifying the dynamic advance control signal. The dynamic preceding control signal creating means creates the dynamic preceding control signal with the new gain amount. Further, in the case of having a display means, a new gain amount is displayed on this display means.

As described above, in the present invention, the dynamic advance control signal is automatically adjusted to the optimum value in accordance with the value indicating the characteristic of the steam temperature change (steam deviation at the change end time of the load command signal). , Or the optimum value of the parameter (gain) that specifies the dynamic preceding control signal is displayed.

[0012]

EXAMPLES Examples of the thermal power plant control device according to the present invention will be described below.

First, before describing the thermal power plant control device according to the present invention, a thermal power plant controlled by this control device will be described with reference to FIG. The thermal power plant 60 of the present embodiment includes a boiler 61 that heats water to generate steam, a steam turbine 74 that is driven by the steam generated by the boiler 61, and a generator 76 that is connected to the steam turbine 74. And a condenser 75 for returning steam from the steam turbine 74 to water. Boiler 6
A steam supply line 70 for guiding steam generated in the boiler 61 to the steam turbine 74 is installed between the steam turbine 74 and the steam turbine 74. The steam supply line 70 is provided with a pressure gauge 71 for measuring the pressure P of the steam passing through it, a thermometer 72 for measuring the temperature T of the steam, and a turbine control valve 73 for adjusting the amount of steam supplied to the steam turbine 74. Has been. In addition, between the condenser 75 and the boiler 61,
A water supply line 80 is installed to supply the water from the condenser 75 to the boiler 61. The water supply line 80 is provided with a water supply pump 81 and a water supply flow meter 82. The boiler 61 is provided with a burner 62 that injects fuel and air into the boiler 61. In this burner 62,
The fuel supply line 63 and the air supply line 66 are connected. The fuel supply line 93 is provided with a fuel amount adjustment valve 64 and a fuel flow meter 65, and the air supply line 66 is provided with an air amount adjustment valve 97.

Next, a first embodiment of the thermal power plant control device according to the present invention will be described with reference to FIGS. 1 to 3 and 5 to 10.
Will be explained. As described above with reference to FIG. 4, the thermal power plant control device 30 of the present embodiment is the thermal power plant 6
The thermal power plant 60 is controlled based on various signals P, T, PW, BF, F from 0. Thermal power plant controller 30
In terms of hardware, as shown in FIG. 3, a control device main body 31, a display device (CRT) 46 for displaying various thermal power plant information, a keyboard 47 for inputting various data, and various data. Hard disk device 48 and floppy disk device 49 for storing information such as
It has and. The control device main body 31 includes a CPU 32 that executes various calculations, a ROM 33 that stores programs and the like for the CPU 32 to execute calculations, a RAM 34 that temporarily stores various data and the like, and a thermal power plant 60. I / O circuit 3 for controlling input / output of signals in
5 and a display device controller 3 for controlling the display device 46
6, a keyboard controller 37 for controlling the keyboard 47, and a hard disk controller 38 for controlling the hard disk device 48.

Next, a schematic functional configuration of the thermal power plant control device 30 will be described with reference to FIG. Control device 30
Is a load command signal setter 9 that outputs a step-shaped load command signal L ₀ that indicates the load of the thermal power plant 60 (output of the generator 76), and limits the rate of change of the step-shaped load command signal L _0. Change rate limiter 10 that outputs a ramp-shaped load command signal L ₁ and a dynamic advance control signal FV for suppressing fluctuation of the main steam temperature at the start of change of the load command signal L ₁ of the load command signal. A function generator 11 that is generated as a function, a timer 12 that measures the time from the change of the load command signal L ₀ , and a turbine that outputs a control valve control signal ASv for controlling the valve opening of the turbine control valve 73. A control valve controller 13, a main steam pressure control controller 14 that outputs a main steam pressure correction signal Pr based on a deviation between the actual main steam pressure P and the main steam pressure set value P ₀ , and a ramp-shaped load command signal. L ₁ and main steam pressure An adder 15 for adding the correction signal Pr, a water supply amount controller 16 for outputting a water supply amount control signal BFp for controlling the drive amount of the water supply pump 81, and a constant gain for the output L ₂ from the adder 15. The multiplier 17 for multiplying G, the actual main steam temperature T and the main steam temperature set value T ₀
Main steam temperature controller 18 that outputs a main steam temperature correction signal Tr based on the deviation between the main steam temperature correction signal Tr, the main steam temperature correction signal Tr, the output L ₃ from the multiplier 17, and the output FV from the function generator 11.
And a fuel amount controller 20 for outputting a fuel amount control signal Fv for controlling the valve opening of the fuel amount control valve 64, and a dynamic advance control signal generated by the function generator 11. The controller 1 is configured to automatically adjust the parameters Ta, K, and Tb of the FV.

Next, the general functional operation of the thermal power plant control device 30 will be described. The load command signal L ₀ output as a step function (shown in FIG. 5) from the load command signal setter 9 is ramped by the change rate limiter 10 (see FIG. 5).
Shown in. ) Is converted to L ₁ . Turbine regulator valve controller 1
3 outputs the turbine control signal ASv based on the deviation between the load command signal (output of the change rate limiter 10) L ₁ converted into the ramp function and the generator output PW to operate the turbine control valve 73. To do. In addition, the main steam pressure controller 14
Outputs a main steam pressure correction signal Tr based on the deviation between the main steam pressure P measured by the pressure gauge 71 and the main steam pressure set value P ₀ . The correction signal Tr and the load command signal (output of the change rate limiter 10) L ₁ converted into the ramp function are added by the adder 15, and the added value is added to the water supply controller 1
It is output as a static advance control signal L ₂ which indicates the target value of 6 (the amount of water supply required according to the change of the load command signal). The water supply controller 16 uses the static advance control signal L
_The water supply amount control signal BFp is output based on the deviation between the target value of the water supply amount indicated by ₂ and the water supply amount BF, and the water supply pump 81 is operated. The main steam temperature control device 18 outputs a main steam temperature correction signal Tr based on the deviation between the main steam temperature T measured by the thermometer 72 and the main steam temperature set value T ₀ . The function generator 11 outputs a dynamic preceding control signal FV (shown in FIG. 5) having a trapezoidal waveform which serves as a correction amount for the excess or deficiency of the fuel amount when the load command signal L ₁ changes. The adder 19 receives the dynamic advance control signal FV and the main steam temperature correction signal Tr.
And a static preceding control signal (output of gain 17) L ₃ obtained by multiplying the output L ₂ of the adder 15 by the gain G, and the added value is the target value of the fuel amount controller 20 (load command signal Target fuel amount signal L ₄ indicating the fuel amount required for the change)
Output as. The fuel amount controller 20 outputs the fuel amount control signal Fv based on the deviation between the target fuel amount indicated by the target fuel amount signal L ₄ and the fuel amount F measured by the fuel amount meter 65 to adjust the fuel amount. Operate the valve 64.

Here, regarding the dynamic advance control signal FV,
This will be described with reference to FIG. Load command signal L indicating load increase
_{When 1} is output, as described above, the turbine control valve 73 is operated based on the deviation between the load command signal L ₁ and the generator output PW, the opening of the valve 73 increases, and the steam turbine 74 The amount of main steam supplied to is increased. When the fuel injection amount from the burner 62 is constant with respect to the increase in the main steam supply amount to the steam turbine 74, the main steam temperature decreases. Therefore, when the load command signal L ₁ indicating the increase in load is output, a signal for increasing the fuel injection amount in advance is dynamically generated before the main steam temperature is reduced in order to suppress the decrease in the main steam temperature. This is the preceding control signal FV. In the present embodiment, the dynamic advance control signal FV has a trapezoidal waveform that rises stepwise and gently falls at a constant inclination. Such a dynamic advance control signal FV is the time Ta from the change start time T1 of the load command signal L ₁ to the output start time T2, the gain K of this advance control signal FV, and the change end time of the load command signal L ₁ ( By defining the convergence time Tb from the signal falling start time T3 to the output ending time (= signal falling end time) T4 (this time is the time to gradually decrease the value of the gain K), Can be determined as in the formula.

FV = 0 (t ≤ T1 + Ta) FV = K (T1 + Ta <t
≤ T3) FV = -K (t-T3) / Tb + K (T3 <t ≤ T3
+ Tb) FV = 0 (T3 + Tb <t) where the value K for determining the dynamic advance control signal FV,
Ta and Tb are called dynamic advance control parameters. The function generator 11 creates a dynamic advance control signal FV based on these dynamic advance control parameters K, Ta, Tb according to the time measured by the timer 12, and outputs this to the adder 19. In order to output the optimum dynamic advance control signal FV in order to suppress the change in the main steam temperature, it is necessary to adjust these dynamic advance control parameters K, Ta, Tb to appropriate values. Therefore, the adjuster 1 executes this adjustment.

Next, the regulator 1 will be described with reference to FIG. As shown in the figure, the regulator 1 has an actual main steam temperature T from the main steam temperature controller 18 and a main steam temperature set value T.
Main steam temperature deviation sampling function 2 for sampling deviation ΔT from _0, and output time T of dynamic preceding control signal FV
From 2 onward, the settling judgment function 3 for judging whether or not the deviation ΔT has become a target value close to 0 (this state is settling) and the main steam temperature deviation ΔT from the time series data Feature amount extraction function 4 for extracting the feature amounts Tma, Tmc, Tmb of the waveform, and the feature amounts Tma, Tmc, Tmb.
Controllability determination function 5 for determining whether or not satisfies the target value, and dynamic advance control parameters Ta, K, Tb if the feature values Tma, Tmc, Tmb do not satisfy the target value.
Correction coefficient estimating function 6 for obtaining correction coefficients CpTa, CpK, CpTb, and dynamic advance control parameters Ta, K, T
The adjustment rule storage function 7 in which the rules necessary for obtaining the correction coefficients CpTa, CpK, and CpTb of b are stored, and the correction coefficient estimation function 6 is used for the current dynamic preceding control parameters Ta, K, and Tb. Correction coefficient CpTa, C
and a parameter calculation function 8 for creating a new dynamic advance control parameter by multiplying pK and CpTb.

The main steam temperature deviation sampling function 2 constantly samples the main steam temperature deviation ΔT from the change start time T1 of the load command signal L ₁ . The settling determination function 3 determines whether or not the main steam temperature deviation ΔT has settled after the output time T2 of the dynamic preceding control signal FV, and operates the feature amount extraction function 4 when the deviation ΔT settles. The characteristic amount extraction function 4 extracts the characteristic amounts Tma, Tmc, and Tmb of the waveform of the main steam temperature from the time series data of the observed main steam temperature deviation ΔT.

Here, the characteristic quantity Tma of the main steam temperature waveform,
Tmc and Tmb will be described with reference to FIG. The figure shows a typical change in the main steam temperature when the load command signal L ₁ changes from a time T1 to a time T3 by a ramp function. As shown in the figure, when the main steam temperature changes, in the present embodiment, the following three are treated as the characteristic quantities of the main steam temperature waveform. That is, the maximum main steam temperature deviation Tma between the load command signal L ₁ changes the start time T1 to change the end time T3, the main steam temperature deviation in the change end time T3 of the load command signal L ₁ Tmc, the load command signal L ₁ The maximum main steam temperature deviation Tmb after the change end time T3 is treated as a characteristic amount of the main steam temperature waveform.
The controllability determination function 5 uses the extracted feature amounts Tma and Tm.
It is determined whether or not c and Tmb satisfy the respective target values,
If it is satisfied, it is determined that the current dynamic advance control parameter is optimum, and the parameter adjustment is not executed.
The controllability determination function 5 uses the feature amounts Tma, Tmc, and Tmb.
If even one of them does not satisfy the target value, the parameter correction coefficient estimation function 6 is operated. The parameter correction coefficient estimation function 6 stores the antecedent part membership function, the consequent part membership function (shown in FIG. 7), and the adjustment rule (shown in FIG. 8) stored in the adjustment rule storage part 7. Then, the parameter modification coefficient is obtained by fuzzy reasoning.

Here, the characteristic quantities Tma and Tm of the main steam temperature
The antecedent part membership function (FIG. 7A) for qualitatively evaluating c and Tmb will be described. As the antecedent part membership function, the maximum main steam temperature deviation Tma from time T1 to time T3, the main steam temperature deviation Tmc at time T3, and the maximum main steam temperature deviation Tm after time T3.
There are three membership functions for each qualitative degree for b. In each membership function, the horizontal axis represents the maximum main steam temperature deviation Tma,
The main steam temperature deviation Tmc and the maximum main steam temperature deviation Tmb are shown, and the vertical axis shows the qualitative degree. Also, N
B, ZE and PB are the names of the functions in the respective antecedent part membership functions, Tma1 to Tma5 and Tmc1.
Tmc5 and Tmb1 to Tmb5 are constants for determining the antecedent part membership function, respectively. Figure 7 (a)
In the membership function of the antecedent part regarding the left maximum main steam temperature deviation Tma, for example, when Tma is Tma ′, T
ma indicates that the degree of NB is 0.2 and the degree of ZE is 0.6.

Next, the consequent part membership function (see FIG. 7).
(B)) will be described. In the figure, the horizontal axis represents the parameter correction coefficient and the vertical axis represents the qualitative degree.
Further, SM, ME, and BG are names of functions in the consequent part membership function, and Cp1 to Cp5 are constants for determining the consequent part membership function. The consequent part membership function is a membership function for converting the qualitative degree obtained by the antecedent part membership function into quantitative parameter correction coefficients CpTa, CpK, and CpTb.

Next, an adjustment rule for connecting the antecedent part membership function and the consequent part membership function (see FIG. 8).
Shown in. ) Will be described. The adjustment rule depends on which function NB, ZE, PB in the membership function of the antecedent part
Which of the functions SM, ME, among the consequent membership functions, depending on whether the qualitative degree for each feature amount is determined
It determines whether to use BG. For example, in the antecedent part membership function, "the feature amount Tma is PB, the feature amount Tmc is ZE, and the feature amount Tmb is PB", and the qualitative degree of each feature amount Tma, Tmc, Tmb is determined. In this case, by referring to Rule 3 corresponding to this, in the consequent part membership function, “correction coefficient C
SM for pK, B for correction coefficient CpTa
G, it is found that SM ”is used for the number of corrections CpTb.

Next, how to actually obtain the parameter correction coefficient using these membership functions and adjustment rules will be described with reference to FIG. here,
It is assumed that, for example, Tma ′, Tmc ′, and Tmb ′ are obtained as the feature amounts of the main steam temperature waveform in the feature amount extraction function 4. These feature quantities Tma ′, Tmc ′, Tm
For b ′, each degree is obtained using the membership function of the antecedent part. At this time, for the characteristic amount Tma ′, the qualitative degree GA is determined by the function PB in the membership function of the characteristic amount Tma, and the characteristic amount Tmc ′ is determined.
, The qualitative degree GC is determined by the function ZE in the membership function of the feature amount Tmc, and the feature amount Tm
For b ′, in the membership function of the feature amount Tmb, the qualitative degree G is obtained by the function PB and the function ZE, respectively.
B and GB 'are defined. Next, refer to the adjustment rule. When obtaining the qualitative degree of each of the feature amounts Tma ′, Tmc ′, Tmb ′, “the feature amount Tma ′ is PB, the feature amount Tmc ′ is ZE, and the feature amount Tmb ′ is PB” is a qualitative degree GA, GC and GB are determined, "feature amount Tma 'is PB, feature amount Tmc' is ZE, and feature amount Tmb 'is ZE".
Since the qualitative degrees GA, GC, GB 'are defined in, the rules 3 and 4 corresponding to these are referred to. Rule 3 defines that “SM is used for correction coefficient CpK”, and Rule 4 is “correction coefficient CpK”.
It is stipulated that ME shall be used for. Therefore, first, according to Rule 3, the function SM in the consequent part membership function is used to obtain Tma ′, Tmc ′,
Among the qualitative degrees GA, GC, and GB with respect to Tmb ′, the weight of the smallest one (here, GB) (the area of the hatched portion in the figure) is obtained. Furthermore, in accordance with Rule 4, using the function ME in the consequent part membership function, the smallest one of the qualitative degrees GA, GC, GB ′ for Tma ′, Tmc ′, Tmb ′ of each feature amount (here,
GA) weight (area of shaded area in the figure) is obtained. Then, the union of the weights is obtained, and the center of gravity GCp of this union is calculated.
Let K be the parameter modification coefficient CpK. Further, the other parameter correction coefficients CpTa and CpTb are similarly obtained.

As described above, the correction coefficients CpK, CpTa, C for the dynamic advance control parameters K, Ta, Tb are set.
When pTb is obtained, the parameter calculation function 8 multiplies the current dynamic preceding control parameters K, Ta, Tb by the parameter corrections CpK, CpTa, CpTb, and sets this value as a new dynamic preceding control parameter. Generator 1
Output to 1. The function generator 11 creates the dynamic advance control signal FV as described above based on the new dynamic advance control parameter. These series of adjustment operations are continued until the controllability determining function 5 satisfies the target values for the respective feature amounts.

Next, the simulation result of the thermal power plant control system of this embodiment will be described with reference to FIG. This simulation is performed using a plant simulator that faithfully reproduces the dynamic characteristics of the thermal power plant 60. This figure shows the response of the main steam temperature when the load command signal is repeatedly changed with a certain change width. As shown in the figure, the main steam temperature greatly fluctuates with respect to the first load increase / decrease. But,
As the load increases and decreases the second and third times, the dynamic advance control signal gradually changes, and the fluctuation of the main steam temperature becomes smaller. The fluctuation of the main steam temperature is suppressed to the minimum with respect to the fifth increase / decrease in load.

As described above, even if the dynamic advance control signal is inappropriate and the fluctuation of the main steam temperature becomes large when the load command signal changes, according to the present embodiment, the main steam temperature waveform Based on the feature quantity of the main steam temperature, fluctuations in the main steam temperature are automatically adjusted in the direction in which the fluctuations in the main steam temperature are reduced, and the dynamic preceding control signal changes, so it is possible to minimize fluctuations in the main steam temperature. it can. Also, in the above,
Although the description has been centered on the control of the main steam temperature, the automatic adjustment of the advanced control parameter according to the present invention is the adjustment of the dynamic advanced control parameter in other control loops such as main steam pressure control, air-fuel ratio control, reheat steam temperature control, etc. It can also be used for.

In this embodiment, the static advance control signal producing means for producing the static advance control signal L ₂ is the adder 1
5, the dynamic advance control signal producing means for producing the dynamic advance control signal FV is constituted by the function generator 11. Further, the steam temperature deviation grasping means, the characteristic amount extracting means, and the parameter calculating means are respectively provided in the regulator 1.
Main steam temperature sampling function 2, feature amount extraction function 4, parameter correction coefficient estimation function 6 and parameter calculation function 8
It is composed of.

By the way, the waveform of the dynamic advance control signal in this embodiment is a trapezoidal waveform which rises stepwise, but the present invention is not limited to this, and for example, as shown in FIG. In addition, a trapezoidal waveform that rises gently with a constant slope and falls gently with a constant slope may be used. In this case, the dynamic advance control parameter is the time Ta from the change start time (= signal rising start time) T1 of the load command signal L ₁ to the signal rising end time T2, the gain K of this advanced control signal FV, and the load command signal. Convergence time Tb from the change end time (= signal falling start time) T3 of L ₁ to the output end time (= signal falling end time) T4
And Then, the advance control signal is determined by the dynamic advance control parameters Ta, K, Tb as in the following equation.

FV = K (t-T1) / Ta (t ≤ T1 + Ta) FV = K (T1 + Ta <t
≤ T3) FV = -K (t-T3) / Tb + K (T3 <t ≤ T3
+ Tb) FV = 0 (T3 + Tb <t) In addition to this, regarding the waveform of the dynamic preceding control signal, various waveforms such as a waveform obtained by interpolating each time with a quadratic curve or a cubic curve are used. Waveforms are possible.

Next, a second embodiment of the thermal power plant controller according to the present invention will be described with reference to FIGS. 12 and 13. As shown in FIG. 12, the control device 30a of the present embodiment is the same as the first embodiment except that the hardware configuration has the manual parameter adjuster 1a, and the software configuration is the first configuration. Regulator 1 in the embodiment
Instead of this, a parameter calculation function 22 having substantially the same function as that of the adjuster 1 is provided, and its output or the like is displayed on the display device 4.
6 is displayed. That is, in the present embodiment, unlike the first embodiment, the regulator 1 does not automatically adjust the dynamic advance control signal, but the parameter calculator 2
The new dynamic advance control parameters and the like obtained in 2 are displayed on the display device 46, the driver is prompted to change the parameters to appropriate values, and the driver himself adjusts the parameters with the manual parameter adjuster 1a. It was made to let. Note that FIG. 12 shows the control device 30a of this embodiment.
In the figure, the manual parameter adjuster 1a and the display device 46 are hardware configurations.

FIG. 13 shows an example of the screen structure of the display device 46. The guidance display screen includes a feature quantity display unit 25 that qualitatively displays the characteristics of the main steam temperature waveform, an adjustment value display unit 26 that displays the current and next dynamic preceding control signal waveforms, and the current and next parameter values. And the adjustment rule display unit 27 that displays the grounds for correcting the dynamic preceding control parameters. The characteristic amount display unit 25 displays the main steam temperature waveform, the load command signal waveform, and the characteristic amount Tm extracted by the characteristic amount extraction function 4 provided in the parameter calculator 22.
a, Tmb, Tmc are displayed. The main steam temperature waveform, main steam temperature at the change start time T1 of the load command signal L ₁ (ΔT ≒ 0), the main steam temperature in the load command signal change end time T3 of L ₁ (ΔT = Tmc), time T
1 to time T3 when the main steam temperature deviation is maximum (ΔT = Tma), and when the main steam temperature deviation is maximum after time T3 (ΔT = Tmb), the main steam temperature at the settling time (ΔT
A simplified one is displayed by connecting (≈0) with a straight line.
The adjustment value display unit 26 displays the current and next parameters,
The waveform of the current dynamic advanced control signal output by the function generator 11 and the waveform of the next dynamic advanced control signal created by the next parameter are displayed. The adjustment rule display unit 25 displays the adjustment rule selected from the adjustment rule storage unit 7 included in the parameter calculator 22 and the rule suitability thereof to show the adjuster the basis of the adjustment.

According to the present embodiment, such a guidance display enables the parameter adjustment work to proceed reliably and smoothly.

[0035]

According to the present invention, the dynamic advance control signal is automatically adjusted to an optimum value in accordance with the value showing the characteristic of the steam temperature change, or the parameter (gain gain) for specifying the dynamic advance control signal is specified. The optimum value of) is displayed. Therefore, when adjusting the dynamic advanced control signal, regardless of the experience and intuition of the operator,
An accurate optimum dynamic advance control signal can be created, and fluctuations in the main steam temperature when the load command signal changes or when the engine is stopped can be suppressed to a minimum.

[Brief description of drawings]

FIG. 1 is a functional block diagram of a regulator of a thermal power plant control device according to a first embodiment of the present invention.

FIG. 2 is a functional block diagram of the thermal power plant control device according to the first embodiment of the present invention.

FIG. 3 is a circuit block diagram of the thermal power plant control device according to the first embodiment of the present invention.

FIG. 4 is a system diagram of a thermal power plant.

FIG. 5 is a diagram of various signal waveforms in the thermal power plant control device according to the first embodiment of the present invention.

FIG. 6 is an explanatory diagram showing a characteristic amount of a main steam temperature waveform when a load command signal changes in the first embodiment according to the present invention.

FIG. 7 is an explanatory diagram showing a membership function used for fuzzy inference according to the first embodiment of the present invention.

FIG. 8 is an explanatory diagram showing an adjustment rule used for fuzzy inference according to the first embodiment of the present invention.

FIG. 9 is an explanatory diagram showing how to obtain a control parameter correction coefficient by fuzzy inference according to the first embodiment of the present invention.

FIG. 10 is an explanatory diagram showing an adjustment simulation result according to the present invention.

FIG. 11 is a diagram of various signal waveforms in the thermal power plant control device of the modified example of the first embodiment according to the present invention.

FIG. 12 is a functional block diagram of a thermal power plant control device according to a second embodiment of the present invention.

FIG. 13 is an explanatory diagram showing a guidance display example in the thermal power plant control device according to the second embodiment of the present invention.

[Explanation of symbols]

1 ... Regulator, 1a ... Manual regulator, 2 ... Main steam temperature deviation sampling function, 3 ... Settling judgment function, 4 ... Feature amount extraction function, 5 ... Controllability judgment function, 6 ... Parameter correction coefficient estimation function, 7 ... Adjustment rule storage unit, 8 ... Parameter calculation function, 9 ... Load command signal setting device, 10 ... Change rate limiter, 1
DESCRIPTION OF SYMBOLS 1 ... Function generator, 12 ... Timer, 13 ... Turbine regulator valve controller, 14 ... Main steam pressure controller, 15, 19 ... Adder, 16 ... Water supply amount controller, 17 ... Multiplier, 18 ... Main steam temperature Controller, 20 ... Fuel amount controller, 22 ... Parameter calculator, 25 ... Characteristic amount display section, 26 ... Adjustment value display section, 27
… Adjustment rule display unit, 30… Thermal power plant control device, 3
1 ... Control device main body, 32 ... CPU, 33 ... ROM, 34
... RAM, 46 ... Display device, 60 ... Thermal power plant, 61
… Boiler, 64… Fuel quantity control valve, 65… Fuel flow meter,
71 ... Pressure gauge, 72 ... Thermometer, 73 ... Turbine regulator valve,
74 ... Steam turbine, 75 ... Condenser, 81 ... Water supply pump, 82 ... Water supply flow meter.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Reference number within the agency FI Technical display location G05D 7/06 Z 9324-3H 23/19 J 9132-3H (72) Inventor Eiji Toyama Hitachi, Ibaraki Prefecture 52-1 Omika-cho, Omi-shi, Hitachi Ltd. Omika Plant, Hitachi Ltd. (72) Inventor Atsushi Yokogawa 5-2-1 Omika-cho, Hitachi City, Ibaraki Hitachi Ltd. Omika Plant, Ltd.

Claims (8)

[Claims] 1. A boiler, a steam turbine driven by steam generated in the boiler, a fuel amount meter for measuring the amount of fuel supplied to the boiler, and a fuel amount control valve for adjusting the amount of fuel. In a control device for a thermal power plant, which comprises a thermometer for measuring the temperature of steam for driving the steam turbine, a static precedent which creates a static advanced control signal corresponding to a load command signal indicating a load of the thermal power plant. A control signal generating means, a gain amount of a dynamic advance control signal for suppressing the temperature fluctuation of the steam at the time of change of the load command signal, as a parameter for specifying at least the dynamic advance control signal, the dynamic A dynamic preceding control signal creating means for creating a preceding control signal, the dynamic preceding control signal and the static preceding control signal are added, and the added result is supplied to the boiler. And a fuel amount control valve according to a deviation between the target amount indicated by the signal from the adding unit and the fuel amount measured by the fuel amount meter. Amount control means for controlling the valve opening degree of, and a steam temperature for grasping a steam temperature deviation between the temperature of the steam measured by the thermometer and a preset steam temperature with respect to the temperature of the steam Among the steam temperature deviations grasped by the deviation grasping means and the steam temperature deviation grasping means, the load deviation of the load command signal is changed, and the steam deviation at the time when the change is finished is extracted as a characteristic amount of the steam temperature change. A feature amount extraction unit, a gain amount of the dynamic preceding control signal is determined according to the steam deviation extracted by the feature amount extraction unit, and the gain amount is newly added to create the dynamic preceding control signal. Na As in amount, it said dynamic pre-controlling signals and parameter calculation means for outputting the creating means, the control device of the thermal power plant, characterized in that it comprises a. 2. A boiler, a steam turbine driven by steam generated in the boiler, a fuel amount meter for measuring the amount of fuel supplied to the boiler, and a fuel amount control valve for adjusting the amount of fuel. In a control device for a thermal power plant, which comprises a thermometer for measuring the temperature of steam for driving the steam turbine, a static precedent which creates a static advanced control signal corresponding to a load command signal indicating a load of the thermal power plant. Control signal generating means, the gain amount of the dynamic preceding control signal for suppressing the fluctuation of the main steam temperature at the time of the change of the load command signal, as a parameter for specifying at least the dynamic preceding control signal,
A dynamic advance control signal producing means for producing the dynamic advance control signal; and, adding the dynamic advance control signal and the static advance control signal, and adding the sum of the fuel to the boiler. A valve opening degree of the fuel amount control valve according to a deviation between the addition amount output as a signal indicating the target amount and the target amount indicated by the signal from the addition unit and the fuel amount measured by the fuel amount meter. A fuel amount control means for controlling, a steam temperature deviation grasping means for obtaining a steam temperature deviation between the temperature of the steam measured by the thermometer and a preset steam temperature with respect to the temperature of the steam, Among the steam temperature deviations grasped by the steam temperature deviation grasping means, a characteristic quantity extracting means for extracting the steam deviation at the time when the load command signal changes and the change ends as a characteristic quantity of the steam temperature change. , According to the steam deviation extracted by the feature amount extraction means, a parameter calculation means for obtaining the gain amount of the dynamic preceding control signal, a display means for displaying the gain amount obtained by the parameter calculation means, A control device for a thermal power plant, comprising: 3. The characteristic amount extracting means includes a maximum steam temperature deviation between a change start time and a change end time of the load command signal, among the steam temperature deviations grasped by the steam temperature deviation grasping means. The controller for a thermal power plant according to claim 1 or 2, wherein the maximum steam temperature deviation after the change end time of the load command signal is extracted. 4. The dynamic preceding control signal is a trapezoidal waveform which rises stepwise and smoothly falls from a change end time of the load command signal. In addition, the rise time from the change start time of the load command signal to the stepwise rise time and the convergence time from the change end time of the load command signal to the output end time of the dynamic preceding control signal are As the parameter, the dynamic preceding control signal is created, and the parameter calculation means determines the rise time and the convergence time which are the parameters according to the steam deviation extracted by the feature amount extraction means. The control device for a thermal power plant according to claim 1, 2 or 3. 5. The dynamic preceding control signal is a trapezoidal waveform that smoothly rises from a change start time of the load command signal and smoothly falls from a change end time of the load command signal. In addition to the gain amount, the signal creating means includes a rising time from a change start time of the load command signal to a rising end time and from a change end time of the load command signal to an output end time of the dynamic preceding control signal. And the convergence time of the as a parameter to create the dynamic preceding control signal, the parameter calculation means, according to the steam deviation extracted by the feature amount extraction means, the rise time and the parameter The control device for a thermal power plant according to claim 1, 2 or 3, wherein a convergence time is obtained. 6. An antecedent membership function for converting the steam deviation extracted by the feature quantity extraction means into a qualitative degree, and a parameter modification coefficient for modifying the qualitative degree with the current parameter. And a storage unit that stores a consequent part membership function to be converted into the antecedent part and a rule that connects the antecedent part membership function and the consequent part membership function, wherein the parameter calculation means is the antecedent part membership function. It is characterized in that the parameter correction coefficient is obtained by fuzzy inference using a function, the consequent part membership function and the rule, and the parameter correction coefficient is multiplied by the current parameter to obtain a new parameter. The control device for a thermal power plant according to claim 1, 2, 3, 4 or 5. 7. The thermal power plant comprises a steam pressure gauge for measuring the pressure of the steam for driving the steam turbine, and the steam pressure gauge measures the pressure of the steam and the pressure of the steam in advance. Provided with a correction signal creating means for creating a correction signal according to the steam pressure deviation of the set steam pressure is determined, the static preceding control signal creating means, depending on the load command signal and the correction signal, The control device for a thermal power plant according to claim 1, 2, 3, 4, 5, or 6, wherein the correction signal is generated. 8. A control device for a thermal power plant, comprising a boiler for generating steam, a steam turbine driven by the steam generated by the boiler, and a thermometer for measuring the temperature of the steam driving the steam turbine. While creating a static preceding control signal according to a load command signal indicating the load of the thermal power plant, a dynamic preceding control signal for suppressing fluctuation of the steam when the load command signal changes. Created according to specific parameters, by these advanced control signals, in a control device that controls the thermal power plant in advance, a feature amount extraction means for extracting a feature amount of the waveform of the steam temperature measured by the thermometer, and the parameter A controller for a thermal power plant, comprising: a parameter adjusting unit that corrects the parameter according to the characteristic amount.