JP3124872B2 - Control equipment for thermal power plant - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control system for a thermal power plant including a boiler for generating steam and a steam turbine driven by the steam generated by the boiler. The present invention relates to a control device for controlling the thermal power plant in advance by using a static preceding control signal corresponding to the indicated load command signal and a dynamic preceding control signal for suppressing the fluctuation of the steam when the load command signal changes.

[0002]

2. Description of the Related Art In the field of thermal power plant automatic control, great improvements have been achieved in plant controllability, such as suppression of main steam temperature fluctuations by feedback control and advance control. Particularly, for a thermal power plant having a large response delay, the preceding control is an effective control. However, control parameters for determining a control signal in these control methods are conventionally manually adjusted by a plant operator while observing a change in a control amount. For example, a control parameter for determining a dynamic preceding control signal for operating the fuel amount (a control signal for shifting from a steady state to another steady state) is based on long-term empirical results from observation results such as fluctuations in main steam temperature. Operators adjust themselves based on their knowledge.

[0003] Attempts regarding automatic adjustment of control parameters include feedback control, especially PI, which accounts for the majority thereof.
Seen in the adjustment of the D controller. For example, JP-A-63
In the technique described in Japanese Patent No. 247801 (hereinafter referred to as Conventional Technique 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 obtaining an overshoot amount and an attenuation coefficient, and a control parameter for qualitatively evaluating the overshoot amount and the attenuation coefficient and estimating a correction value of the PID control parameter by fuzzy inference. When the overshoot amount and the damping coefficient exceed the allowable ranges, the control parameter of the PID controller is automatically adjusted by providing controllability determining means for causing the control parameter correcting means to function.

On the other hand, regarding the advanced control technology in the thermal power plant automatic control field, for example, Japanese Patent Publication No. 4-2992
No. 2 (hereinafter referred to as Conventional Technique 2). Although the present technology is a technology for suppressing main steam pressure fluctuation, it is a technology similar to the present invention as a prior control technology in the thermal power plant automatic control field. In this technology, the main steam pressure is regulated by manipulating the input amount such as the water supply amount and 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 due to the main steam pressure deviation. When controlling to a value, a dynamic preceding control signal for the main steam pressure is output in response to a change in the load command signal from the start of the change in the load command signal to correct the static control signal.
Also, set a predetermined time before the completion of the change of the load command signal,
At a set point in time, the dynamic preceding control signal is turned off or converged. With the preceding control method, the change in the main steam pressure at the time of a load change and at the time of starting and stopping is minimized.

[0005]

According to the prior art 1,
The PID control parameter can be automatically and efficiently adjusted from the control response waveform shape observed when the target value changes or when a disturbance is applied. However, the prior art 1 does not consider automatic control parameter adjustment in the case where effective preceding control is also used for a thermal power plant having a large response delay. Also,
According to the prior art 2, by performing the preceding control, it is possible to minimize fluctuations in the main steam pressure when the load command signal changes and when the start and stop are performed. However, prior art 2 does not consider adjustment of the preceding control parameters.

That is, in each of the prior arts,
The control parameters that determine the advance control signal must be adjusted by the plant operator based on his or her own experience.This is a burden on the operator, and if incorrect adjustment is made, effective advance control cannot be performed. There is a problem of disappearing.

The present invention has been made in view of such a conventional problem. In adjusting the dynamic preceding control signal, an appropriate optimal dynamic preceding control signal can be 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, which can minimize the fluctuation of the main steam temperature at the time of a change in a load command signal or at the time of starting and stopping.

[0008]

In order to achieve the above object, a control device for a thermal power plant includes an actual temperature of steam for driving a steam turbine and a set steam temperature predetermined for the temperature of the steam. Steam temperature deviation grasping means for grasping the steam temperature deviation of the steam temperature deviation grasped by the steam temperature deviation grasping means, from the change start time to the change end time of the load command signal indicating the load of the thermal power plant .
Between the maximum steam temperature deviation and the change of the load command command
At the end of the steam command deviation and the load command signal
The maximum time between the hour and the time when the steam temperature is settled
A steam temperature deviation, and a feature value extraction unit that extracts the feature value as a feature value; and the parameter based on three types of the feature values.
Adjustment rule storage hand that stores adjustment rules for adjustment
Stage and three kinds of fronts extracted by the feature amount extracting means.
And the adjustment amount stored in the adjustment rule storage unit.
The parameter including the gain amount is obtained by using the adjustment rule.
Parameter calculating means for obtaining a parameter, setting the parameter as a new parameter, and outputting the parameter to the dynamic preceding control signal generating means.

Here, the parameter calculating means stops calculating the parameter including the new gain amount.
The parameters may be displayed on the display means. The parameter calculation means is a so-called fuzzy inference,
A new parameter may be obtained from the extracted feature amount.

[0010]

The temperature of the steam driving 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.
In the characteristic amount extracting means, the steam deviation at the change end time of the load command signal is extracted as the characteristic amount of the steam temperature change from the steam temperature deviations grasped by the steam temperature deviation grasping means. In the parameter calculating means, a gain amount of the dynamic preceding control signal is obtained according to the steam deviation extracted by the characteristic amount extracting means. This gain amount is output to the dynamic precedence control signal generation means as one of the parameters for specifying the dynamic precedence control signal. In the dynamic advance control signal creating means, a dynamic advance control signal is created based on the new gain amount. In the case of a display device having a display means, a new gain amount is displayed on the display means.

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

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a thermal power plant control apparatus 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 the thermal power plant 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. A condenser 75 for returning steam from the steam turbine 74 to water. Boiler 6
A steam supply line 70 for guiding steam generated by the boiler 61 to the steam turbine 74 is provided between the steam turbine 1 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 therethrough, 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. Have been. Also, between the condenser 75 and the boiler 61,
A water supply line 80 for supplying water from the condenser 75 to the boiler 61 is laid. 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 for injecting 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 a thermal power plant control apparatus according to the present invention will be described with reference to FIGS. 1 to 3 and FIGS.
This will be described with reference to FIG. As described above with reference to FIG. 4, the thermal power plant control device 30 of the present embodiment
The thermal power plant 60 is controlled based on various signals P, T, PW, BF, and F from 0. Thermal power plant control device 30
In terms of hardware, as shown in FIG. 3, the control device main body 31, a display device (CRT) 46 for displaying various types of thermal power plant information, a keyboard 47 for inputting various data and the like, Hard disk device 48 and floppy disk device 49 for storing
And The control device main body 31 includes a CPU 32 for executing various calculations, a ROM 33 for storing programs for the CPU 32 to execute calculations, a RAM 34 for temporarily storing various data, and the like. I / O circuit 3 for controlling signal input / output in
5 and a display controller 3 for controlling the display 46
6, a keyboard controller 37 for controlling a keyboard 47, and a hard disk controller 38 for controlling a 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 setting device 9 that outputs a step-like load command signal L ₀ for instructing the load of the thermal power plant 60 (output of the generator 76), and restricts the rate of change of the step-like load command signal L _0. Te and the change rate limiter 10 which outputs a ramp load command signal L _1, the load command signal dynamic preceding control signal FV for suppressing the fluctuation of the main steam temperature at start of change in the load command signal L ₁ A function generator 11 for generating a function, a timer 12 for measuring the time from the time when the load command signal L ₀ changes, and a turbine for outputting a control valve ASv for controlling the valve opening of the turbine control valve 73. a control valve controller 13, a main steam pressure control regulator 14 for outputting the actual main steam pressure P and the main steam pressure setpoint deviation based main steam pressure correction signal Pr with P _0, ramp load command signal L ₁ and the main steam pressure An adder 15 for adding the correction signal Pr, and 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, a constant gain the output L ₂ from the adder 15 A multiplier 17 for multiplying G, an actual main steam temperature T and a main steam temperature set value T ₀
Output FV from output L ₃ and the function generator 11 from the main steam temperature controller 18 for outputting a main steam temperature correction signal Tr based on the deviation between a main steam temperature correction signal Tr multiplier 17
, A fuel amount controller 20 for outputting a fuel amount control signal Fv for controlling the valve opening of the fuel amount adjusting valve 64, and a dynamic leading control signal generated by the function generator 11. And an adjuster 1 for automatically adjusting the parameters Ta, K, and Tb of the FV.

Next, a schematic functional operation of the thermal power plant control device 30 will be described. The load command signal L ₀ output from the load command signal setting device 9 as a step function (shown in FIG. 5) is output from a ramp function (FIG.
Shown in ) Is converted to L _1. Turbine control valve controller 1
3 outputs a turbine acceleration control signal ASv based on the deviation between the (output of the change rate limiter 10) lamp transformed load command signal to the function L ₁ and the generator output PW, operating the turbine governor valve 73 I do. In addition, the main steam pressure controller 14
Outputs a main steam pressure correction signal Pr 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 (output of the change rate limiter 10) Pr and the lamp converted load command signal to the function L ₁ and are added by the adder 15, that this is subject to water supply amount controller 1
Target value of 6 is output (water supply amount required with the load command signal change) as a static pre-controlling signals L ₂ which will be shown. The water supply amount controller 16 controls the static precedence control signal L
_The water supply amount control signal BFp is output based on the deviation between the water supply amount target value and the water supply amount BF indicated by ₂ to operate the water supply pump 81. The main steam temperature controller 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 . From the function generator 11 outputs a dynamic preceding control signal FV trapezoidal waveform as the excess or deficiency correction amount of the fuel quantity at the time of change in the load command signal L ₁ (. Shown in FIG. 5). The adder 19 outputs the dynamic preceding control signal FV and the main steam temperature correction signal Tr.
If, by adding the output L (the output of the gain 17) ₂ Static preceding control signal multiplied by the gain G to L ₃ of the adder 15, the target value of the added value fuel quantity controller 20 (load command signal A target fuel amount signal L ₄ indicating the amount of fuel necessary for the change)
Output as Fuel amount controller 20, based on the deviation between the fuel amount F measured at the target fuel amount and the fuel meter 65 indicated by the target fuel quantity signal L _4, and outputs a fuel quantity control signal Fv, fuel quantity adjusting Operate the valve 64.

Here, regarding the dynamic preceding 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, based on the deviation between the load command signal L ₁ and the generator output PW, the turbine governor valve 73 is operated, the opening degree of the valve 73 increases, the steam turbine 74 The amount of main steam supplied to the tank increases. 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 showing the load increase is output, in order to suppress the reduction of the main steam temperature, before the main steam temperature is lowered, the dynamic signal for increasing the advance fuel injection amount This is the advance control signal FV. In the present embodiment, the dynamic leading control signal FV has a trapezoidal waveform that rises in a stepwise manner and gradually falls with a constant slope. Such dynamic preceding control signal FV, the load command signal L ₁ time Ta from the change start time T1 until the output start time T2, the gain K of the preceding control signal FV, the load command signal L ₁ changes the end time ( By setting a convergence time Tb from the signal falling start time T3 to the output end time (signal falling end time) T4 (this time is a time for gradually decreasing the value of the gain K), Can be determined as in the following equation.

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 values K,
Ta and Tb are called dynamic preceding control parameters. The function generator 11 creates a dynamic advance control signal FV according to the time measured by the timer 12 based on these dynamic advance control parameters K, Ta, and Tb, and outputs this to the adder 19. In order to output the optimal dynamic preceding control signal FV in order to suppress a change in the main steam temperature, it is necessary to adjust these dynamic preceding control parameters K, Ta, and Tb to appropriate values. Therefore, the adjuster 1 performs this adjustment.

Next, the adjuster 1 will be described with reference to FIG. As shown in the figure, the regulator 1 includes 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 advance control signal FV
The settling determination function 3 determines whether or not the deviation ΔT has become a target value close to 0 after 2 (this state is settled), and the main steam temperature is determined from the time-series data of the main steam temperature deviation ΔT. A feature value extraction function 4 for extracting feature values Tma, Tmc, Tmb of a waveform, and feature values Tma, Tmc, Tmb
Is a controllability determining function 5 for determining whether or not the target value satisfies a target value, and the dynamic preceding control parameters Ta, K, Tb if the feature values Tma, Tmc, Tmb do not satisfy the target value.
Coefficient estimating function 6 for obtaining the correction coefficients CpTa, CpK, CpTb of the dynamic control parameters Ta, K, T
The adjustment rule storage function 7 in which rules necessary for obtaining the correction coefficients CpTa, CpK, and CpTb of b are stored, and the correction coefficient estimation function 6 obtains the current dynamic preceding control parameters Ta, K, and Tb. Correction coefficient CpTa, C
and a parameter calculation function 8 for multiplying pK and CpTb to create a new dynamic preceding control parameter.

The main steam temperature deviation sampling function 2, constantly sampling the main steam temperature deviation ΔT from the load command signal L ₁ changes the start time T1. 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 quantity extraction function 4 when the deviation ΔT has settled. The feature value extraction function 4 extracts feature values 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 amount Tma,
Tmc and Tmb will be described with reference to FIG. The figure is intended to load command signal L ₁ showed typical changes in the main steam temperature when varying ramp function from time T1 to time T3. 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 determining function 5 includes the extracted feature amounts Tma and Tm.
It is determined whether c and Tmb satisfy respective target values,
If satisfied, the current dynamic preceding control parameters are determined to be optimal, and no parameter adjustment is performed.
The controllability judging function 5 includes the feature amounts Tma, Tmc, Tmb
If any one of them does not satisfy the target value, the parameter correction coefficient estimation function 6 is operated. The parameter correction coefficient estimating 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 unit 7. To obtain a parameter correction coefficient by fuzzy inference.

Here, the characteristic quantities Tma, Tm of the main steam temperature
An antecedent membership function (FIG. 7A) for qualitatively evaluating c and Tmb will be described. The antecedent membership functions include a maximum main steam temperature deviation Tma from time T1 to time T3, a main steam temperature deviation Tmc at time T3, and a maximum main steam temperature deviation Tm after time T3.
For b, there are three membership functions to find the respective qualitative degrees. 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 a qualitative degree. Also, N
B, ZE, and PB are the names of the functions in the respective antecedent part membership functions, and are Tma1 to Tma5, Tmc1 to Tma1.
Tmc5 and Tmb1 to Tmb5 are constants for determining the antecedent part membership function, respectively. FIG. 7 (a)
In the membership function of the antecedent part regarding the maximum main steam temperature deviation Tma on the left, for example, when Tma is Tma ',
ma indicates that the degree of NB is 0.2 and the degree of ZE is 0.6.

Next, the consequent part membership function (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.
SM, ME, and BG are the names of functions in the consequent part membership function, respectively, 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 (FIG. 8)
Shown in ) Will be described. The adjustment rule is determined by which function NB, ZE, or PB in the antecedent membership function.
Depending on whether the qualitative degree for each feature is determined, which of the consequent part membership functions SM, ME,
This determines whether to use BG. For example, in the antecedent part membership function, the qualitative degree of each of the feature amounts Tma, Tmc, and Tmb is determined by “the feature amount Tma is PB, the feature amount Tmc is ZE, and the feature amount Tmb is PB”. 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 clear 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 characteristic amounts of the main steam temperature waveform in the characteristic amount extraction function 4. These feature values Tma ′, Tmc ′, Tm
The degree of each of b ′ is determined using the antecedent membership function. At this time, the qualitative degree GA is determined by the function PB in the membership function of the feature amount Tma 'for the feature amount Tma', and the feature amount Tmc '
, 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 ′, the qualitative degree G is represented by the function PB and the function ZE in the membership function of the feature amount Tmb.
B and GB 'are determined. Next, reference is made to the adjustment rules. When obtaining the qualitative degree of each of the feature amounts Tma ′, Tmc ′, and Tmb ′, the qualitative degree GA with “the feature amount Tma ′ is PB, the feature amount Tmc ′ is ZE, and the feature amount Tmb ′ is PB”, GC and GB are determined, and "the feature amount Tma 'is PB, the feature amount Tmc' is ZE, and the feature amount Tmb 'is ZE"
The qualitative degrees GA, GC, and GB 'are defined in the above, and the rules 3 and 4 corresponding to these are referred to. Rule 3 stipulates that “SM is used for correction coefficient CpK”, and Rule 4 specifies “correction coefficient CpK”.
The use of ME is specified. Therefore, first, according to rule 3, using the function SM in the consequent part membership function, Tma ′, Tmc ′,
Among the qualitative degrees GA, GC, and GB with respect to Tmb ', the weight (the area of the hatched portion in the figure) of the smallest one (here, GB) is obtained. Further, in accordance with Rule 4, using the function ME in the consequent part membership function, the smallest one of the qualitative degrees GA, GC, and GB 'of each feature amount with respect to Tma', Tmc ', and Tmb'. (here,
GA) (the area of the hatched portion in the figure). Then, a union of the weights is obtained, and the center of gravity GCp of the union is calculated.
Let K be a parameter correction coefficient CpK. The other parameter correction coefficients CpTa and CpTb are obtained in the same manner.

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

Next, a simulation result of the thermal power plant control device of the present embodiment will be described with reference to FIG. This simulation is executed using a plant simulator that faithfully reproduces the dynamic characteristics of the thermal power plant 60. FIG. 3 shows the response of the main steam temperature when the load command signal is repeatedly changed with a certain fixed width. As shown in the figure, the main steam temperature fluctuates greatly with respect to the first load increase / decrease change. But,
As the number of times of increase and decrease of the load increases in the second and third times, the dynamic preceding control signal gradually changes, and the fluctuation of the main steam temperature decreases. Then, with respect to the fifth increase / decrease change of the load, the fluctuation of the main steam temperature is minimized.

As described above, according to the present embodiment, even when the dynamic preceding control signal is inappropriate and the load command signal changes, the main steam temperature greatly fluctuates. The dynamic preceding control parameter is automatically adjusted in the direction in which the fluctuation of the main steam temperature becomes smaller based on the characteristic amount of the above, and the dynamic preceding control signal changes, so that the fluctuation of the main steam temperature can be minimized. it can. In the above,
Although the control of the main steam temperature has been mainly described, the automatic adjustment of the preceding control parameters according to the present invention is performed by adjusting the dynamic preceding control parameters in other control loops such as main steam pressure control, air-fuel ratio control, and reheat steam temperature control. Can also be used.

[0029] In the present embodiment, a static pre-controlling signal generating means for generating a static preceding control signal L ₂ adder 1
The dynamic advance control signal generating means for generating the dynamic advance control signal FV comprises a function generator 11. Further, the steam temperature deviation grasping means, the feature quantity extracting means, and the parameter calculating means are provided in the adjuster 1, respectively.
Main steam temperature sampling function 2, feature quantity extraction function 4, parameter correction coefficient estimation function 6, and parameter calculation function 8
It is composed of

The waveform of the dynamic leading control signal in this embodiment is a trapezoidal waveform rising in a stepwise manner. However, the present invention is not limited to this. For example, as shown in FIG. Alternatively, a trapezoidal waveform that rises gently at a constant inclination and falls gently at a constant inclination may be used. In this case, the dynamic preceding control parameters, the load command signal L ₁ changes the start time (= signal rise start time) time from T1 until the signal rising end time T2 Ta, gain K in the preceding control signal FV, the load command signal change end time of L ₁ (= signal falling start time) T3 from the output end time (= signal falling end time) convergence time until T4 Tb
And The advance control signal is determined by the dynamic advance control parameters Ta, K, and 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, the waveform of the dynamic leading control signal may be various other waveforms, such as a waveform obtained by interpolating between time points using a quadratic curve or a cubic curve. Waveforms are possible.

Next, a second embodiment of the thermal power plant control apparatus according to the present invention will be described with reference to FIGS. As shown in FIG. 12, the control device 30a of this embodiment is the same as the first embodiment except that the hardware configuration includes a manual parameter adjuster 1a. Regulator 1 in the embodiment of FIG.
Instead, a parameter calculation function 22 having substantially the same function as that of the adjuster 1 is provided, and its output and the like are displayed on the display
6 is displayed. That is, in the present embodiment, the controller 1 does not automatically adjust the dynamic leading control signal as in the first embodiment, but the parameter calculator 2
The new dynamic precedence control parameter and the like obtained in step 2 are displayed on the display device 46, and the driver is urged to change the parameter to an appropriate value, and the driver himself adjusts the parameter with the manual parameter adjuster 1a. It is intended to be. 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 configuration of the display device 46. As shown in FIG. The guidance display screen includes a feature amount 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 an adjustment rule display unit 27 for displaying the basis of the dynamic preceding control parameter correction. The characteristic amount display section 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, and 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
The main steam temperature (ΔT = Tma) when the main steam temperature deviation becomes maximum between 1 and time T3, and the main steam temperature (ΔT = when the main steam temperature deviation becomes maximum after time T3) Tmb), main steam temperature at settling time (ΔT
(# 0) is connected by a straight line, and a simplified version is displayed.
The adjustment value display section 26 displays the current and next parameters,
The waveform of the current dynamic advance control signal output from the function generator 11 and the waveform of the next dynamic advance control signal created with the next parameter are displayed. Further, 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 conformance, and indicates the basis of the adjustment to the coordinator.

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

[0035]

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

[Brief description of the 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 illustrating 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 for illustrating a characteristic amount of a main steam temperature waveform when a load command signal changes according to the first embodiment of 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 adjustment rules 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 showing various signal waveforms in a thermal power plant control device according to a modification of the first embodiment of 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 illustrating a guidance display example in the thermal power plant control device according to the second embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Adjuster, 1a ... Manual adjuster, 2 ... Main steam temperature deviation sampling function, 3 ... Settling judgment function, 4 ... Feature 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 unit, 10: change rate limiter, 1
DESCRIPTION OF SYMBOLS 1 ... Function generator, 12 ... Timer, 13 ... Turbine control 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: feature amount display unit, 26: adjustment value display unit, 27
... adjustment rule display section, 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 amount control valve, 65 ... fuel flow meter,
71: pressure gauge, 72: thermometer, 73: turbine control valve,
74: a steam turbine; 75: a condenser; 81: a feedwater pump; 82: a feedwater flow meter.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification code FI G05D 7/06 G05D 7/06 Z 23/19 23/19 J (72) Inventor Eiji Toyama 5-chome 2, Omika-cho, Hitachi City, Ibaraki Prefecture No. 1 Hitachi, Ltd. Omika Plant (72) Inventor Atsushi Yokokawa 5-2-1 Omika-cho, Hitachi City, Ibaraki Prefecture Hitachi, Ltd. Omika Plant (56) References JP-A-5-53605 (JP, A) JP-A-4-127205 (JP, A) JP-A-4-203708 (JP, A) JP-A-6-222808 (JP, A) JP-A-5-265507 (JP, A) Eiji Toyama 3 people, "Fuzzy application auto tuning technique and application to thermal power plant", Hitachi Review, Ohmsha Co., Ltd., February 1, 1993, Vol. 75, No. 2, p. 25-28 Eiji Toyama and 2 others, “Auto-tuning System for Thermal Power Plant Control”, Proceedings of the 72nd Annual General Meeting of the Japan Society of Electrical Engineers, NEC Corporation, June 1993 3rd, p. 12-13 (58) Fields investigated (Int.Cl. ⁷ , DB name) G05B 13/00-13/04 G05B 11/32 G05B 11/36 G05D 23/19 F01K 13/02 F22B 35/00

Claims (5)

(57) [Claims] 1. A boiler, a steam turbine driven by steam generated by the boiler, a fuel meter for measuring an amount of fuel supplied to the boiler, a fuel amount control valve for adjusting the amount of fuel, A control device for a thermal power plant, comprising: a thermometer for measuring a temperature of steam for driving the steam turbine; wherein a static advanced control signal corresponding to a load command signal indicating a load of the thermal power plant is generated. A control signal generating means, and a gain amount of a dynamic preceding control signal for suppressing a temperature variation of the steam when the load command signal is changed, at least as a parameter for specifying the dynamic preceding control signal, Dynamic preceding control signal creating means for creating a leading control signal; adding the dynamic leading control signal and the static leading control signal; and supplying the sum to the boiler Adding means for outputting a signal indicating the target amount of the fuel, and the fuel amount adjusting valve according to a deviation between the target amount indicated by the signal from the adding means and the fuel amount measured by the fuel meter. A fuel amount control means for controlling the valve opening degree, and a steam temperature for grasping a steam temperature deviation between the temperature of the steam measured by the thermometer and a set steam temperature predetermined for the temperature of the steam. Deviation grasping means, and, among the steam temperature deviations grasped by the steam temperature deviation grasping means, a change end time from a change start time of the load command signal.
Maximum steam temperature deviation until the end time and the load command signal
Steam temperature deviation at the end time of the change of the load command signal
From the end time of the change of the steam until the steam temperature is settled.
A feature amount extracting means for extracting the maximum steam temperature deviation between as a feature amount, and adjusting the parameter based on the three types of the feature amounts.
Adjustment rule storage means for storing an adjustment rule for storing the three types of features extracted by the feature quantity extraction means
The amount and the adjustment stored in the adjustment rule storage means.
The parameter including the gain amount by using the
And a parameter calculating means for obtaining the parameter as a new parameter and outputting the parameter as a new parameter to the dynamic preceding control signal generating means. 2. A boiler, a steam turbine driven by steam generated by the boiler, a fuel meter for measuring an amount of fuel supplied to the boiler, a fuel amount control valve for adjusting the amount of fuel, A control device for a thermal power plant comprising: a thermometer for measuring a temperature of steam for driving the steam turbine; Control signal creation means, and a gain amount of a dynamic advance control signal for suppressing temperature fluctuation of the steam at the time of change of the load command signal, at least as a parameter for specifying the dynamic advance control signal. A dynamic leading control signal creating means for creating the dynamic leading control signal; and adding the dynamic leading control signal and the static leading control signal to the boiler. Adding means for outputting as a signal indicating a target amount of the fuel to be supplied; and adjusting the fuel amount according to a deviation between the target amount indicated by the signal from the adding means and the fuel amount measured by the fuel meter. Fuel amount control means for controlling the valve opening degree of the valve; and a steam temperature for obtaining a steam temperature deviation between the temperature of the steam measured by the thermometer and a set steam temperature predetermined for the temperature of the steam. Deviation grasping means, and, among the steam temperature deviations grasped by the steam temperature deviation grasping means, a change end time from a change start time of the load command signal.
Maximum steam temperature deviation until the end time and the load command signal
Steam temperature deviation at the end time of the change of the load command signal
From the end time of the change
And a feature amount extracting means for extracting the maximum steam temperature deviation between the above as a feature amount, and adjusting the parameter based on the three types of the feature amounts.
Adjustment rule storage means for storing an adjustment rule for storing, and three types of the features extracted by the feature quantity extraction means
The amount and the adjustment stored in the adjustment rule storage means.
The parameter including the gain amount by using the
Parameter calculating means for determining the parameter, and the parameter calculating means
The parameters and para previously obtained including gain amount
Meter and the newly determined parameter.
The waveform of the dynamic preceding control signal and the parameter obtained last time
The waveform of the dynamic preceding control signal determined by the meter and the temperature
Temperature waveform of the steam measured by the
And the three types of feature amounts extracted by
When the parameter calculation means determines the new parameter
Of the adjustment rules that were the basis, at least,
The newly determined parameters and the previously determined parameters
And a display means for displaying the parameters . 3. The fire according to claim 1, wherein
In the control device for a power plant, the dynamic preceding control signal rises stepwise, and
A trapezoidal shape that smoothly falls from the end time of the load command signal change
In the waveform of the above, the dynamic preceding control signal generating means outputs
From the change start time of the load command signal,
Rise time up to the rise time and change in the load command signal
From the end time to the output end time of the dynamic preceding control signal.
And the convergence time as the parameter,
And the parameter calculation means is provided by the feature quantity extraction means.
The three extracted feature amounts and the adjustment rule storage
Using the adjustment rules stored in the means,
At the time of rising, together with the gain amount, which is a parameter.
And a convergence time.
Control device. 4. The fire according to claim 1, wherein
In the power plant control device, the dynamic preceding control signal is a start of the change of the load command signal.
Smoothly rises from the time and finishes changing the load command signal
The dynamic precedence control signal generating means has a trapezoidal waveform falling smoothly from time,
At the end of the rise from the change start time of the load command signal.
And the end time of the change of the load command signal.
Convergence time from the output end time of the dynamic preceding control signal to
The dynamic preceding control signal is created using
And the parameter calculation means is provided by the feature quantity extraction means.
Before Symbol feature amount of the extracted three, the adjustment rule storage
Using the adjustment rules stored in the means,
At the time of rising, together with the gain amount, which is a parameter.
And a convergence time.
Control device. 5. The fire according to claim 1, wherein
In the control device for a power plant, the adjustment rules stored in the storage unit are the three types of the features extracted by the feature amount extraction unit.
Antecedent membership relationship to convert quantity to qualitative degree
Modify the current parameters with the number and the qualitative degree
Consequent membership to convert to parameter correction coefficient for
Function, antecedent membership function and consequent member
A rule for associating the antecedent part with the membership function.
Number, using the consequent part membership function and the rule
The parameter correction coefficient is obtained by fuzzy inference,
Multiply the current parameter by the parameter correction factor
And obtain new parameters.
Control unit for thermal power plant.