JPH07293279A - Control for gas turbine and device therefor - Google Patents

Abstract

PURPOSE:To adjust the fuel flow rate in correspondence with the output signal by judging if the variation of the output demand signal is due to noise or output variation demand, and outputting the feed/forward operation quantity of the fuel supply quantity corresponding to the demanded output. CONSTITUTION:A gas turbine controller is equipped with an accelertation control means 1 for preventing the surging, deceleration means 3 for preventing the blasting-off, and further equipped with the low and high rank selecting means 4 and 5. In this case, a feed/forward control means 2 is installed, and if the output demand signal varies, it is judged if the true variation demand of output exists or not, according to the variation width. Accordingly, if it is judged that the true variation demand of output exists, the operation quantity related to the fuel supply quantity corresponding to the demanded varation output is inputted into a low rank selecting means 4. The low rank operation quantity among the operation quantity supplied from the feed/forward control means 2 and the acceleration control rmeans 1 is inputted into a high rank selecting means 5 by the low rank selecting means 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas turbine control method and control apparatus. More specifically, the present invention relates to a control method and a control apparatus for a gas turbine that also uses feedforward control.

[0002]

2. Description of the Related Art Conventionally, in the control of a jet engine or a gas turbine (hereinafter sometimes simply referred to as a gas turbine), as shown in FIG. 3, the relationship between the output and the engine speed is preset. Then, when a certain output command is given, the fuel supply amount is controlled so that the engine speed corresponds to the output. Further, in this control, acceleration control is performed to prevent surging and deceleration control is performed to prevent blowout, and the operation amount from the deceleration means is input to the high-level selector. The high-level selector outputs the higher one of the operation amounts from the low-level selector and the operation amount from the deceleration control means as the fuel flow rate command value.

According to such a control method, it is possible to finally reach the target output, but the output is changed because the fuel supply amount is controlled through the rotational speed of the engine having a large inertia. It takes a long time to reach the commanded output from the time when the request is made.

As described above, the conventional gas turbine control method has a problem that the commanded output cannot be reached quickly. Although such a problem may not be a fatal defect in a commercial aircraft, it may cause a fatal situation in which a military aircraft is shot down by an enemy aircraft or an enemy missile.

As described above, in the conventional gas turbine control method, since the fuel supply amount is controlled through the engine speed control, the response of the engine must be low. There's a problem.

[0006] Here, if the fuel flow rate is directly controlled without going through the engine speed control using the acceleration control or deceleration control as described above, surging may occur,
Another problem arises that blowout may occur. In addition, if the fuel flow rate is changed greatly with respect to the output request signal, it is likely to be affected by noise, and as a result, the fluctuation of the steady output becomes large, and the limit value defined in the MIL cannot be met. There is also.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems of the prior art, and provides a control method and a control apparatus for a gas turbine capable of adjusting the fuel flow rate in response to an output signal. It is an object.

[0008]

According to the gas turbine control method of the present invention, the amount of fuel supply is controlled by an arithmetic processing unit through acceleration control for preventing surging and deceleration control for preventing blowout. In the control method of the gas turbine that is used, when there is a change in the output request signal, the procedure for determining whether there is a true output change request according to the fluctuation range and the true output change request signal If it is determined that the operation amount related to the fuel supply amount corresponding to the output change request signal is generated, the operation amount and the operation amount by the acceleration control are compared, and, of the two,
A procedure of selecting a lower one and a procedure of comparing the selected operation amount and the operation amount by deceleration control and selecting the higher one of them and outputting the fuel flow rate command value are included. It is characterized in that

On the other hand, the gas turbine control device of the present invention is a gas having acceleration control means for preventing surging, deceleration control means for preventing blowout, low level selection means, and high level selection means. In the turbine control device, a feedforward control unit is provided, and when the output request signal changes, the feedforward control unit determines whether or not there is a true output change request according to the change width, When it is determined that there is a true output change request, the operation amount related to the fuel supply amount corresponding to the requested change output is input to the low-order selection means, and the low-order selection means is operated by the feedforward control means and the acceleration control means. The operation amount of the lower level is input to the high level selecting means, and the high level selecting means controls the operation amount from the low level selecting means and Among the operation amount from the serial deceleration control means, and outputs a fuel flow rate command value to select the high-level operation amount.

[0010]

If the output request signal fluctuates, it is determined whether the fluctuation is due to noise or an output change request. As a result, when it is determined that the change is based on the output change request, the feedforward manipulated variable of the fuel supply amount corresponding to the requested output is output. The operation amount is compared with the operation amount by the acceleration control, and the lower operation amount is selected. Then, the selected operation amount is compared with the operation amount by the deceleration control, and the higher operation amount is selected and output as the fuel flow rate command value. Therefore, it is possible to improve the output responsiveness while preventing unnecessary fluctuations in the output due to noise, and preventing the surging and the blowout.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described based on embodiments with reference to the accompanying drawings, but the present invention is not limited to such embodiments.

FIG. 1 shows a block diagram of a main part of a control device used in the gas turbine control method of the present invention. This control device has an acceleration control means 1, a feedforward control means 2, a deceleration control means 3 and a low level selection means 4. And the high-order selection means 5 are the main parts.

The acceleration control means 1 is the same as a known acceleration control device conventionally used in the control of a gas turbine in order to prevent surging, and therefore a detailed description of its configuration will be omitted.

The deceleration control means 3 is the same as a known deceleration control device conventionally used in the control of a gas turbine in order to prevent blowout, and therefore the detailed description of its configuration is also omitted.

The low-level selecting means 4 is similar to a known low-level selector conventionally used in gas turbine control in order to select a low-level one from the input manipulated variables. The detailed description of the configuration is also omitted.

The high level selecting means 5 is similar to a known high level selector conventionally used in the control of a gas turbine in order to select a high level from the input manipulated variables. The detailed description of the configuration is also omitted.

When the output request signal fluctuates, the feedforward control means 2 judges whether or not the fluctuation is due to noise, and when it judges that the fluctuation is not due to noise, the fuel corresponding to the output request signal. It has a function of outputting the feedforward manipulated variable of the flow rate. More specifically, as shown in FIG. 2, the fuel flow rate corresponding to the output request signal is selected from the fuel flow rate table 21, and the manipulated variable calculation line 2a for calculating the manipulated variable corresponding to the selected fuel flow rate is used. It is composed of a noise removal line 2b for preventing an erroneous manipulated variable from being output as if an output change request had been made even though no change was requested. A product obtained by multiplying the signals of the operation amount calculation line 2a and the noise removal line 2b is output from the feedforward control means 2 as a feedforward operation amount.

The structure of the noise removal line 2b will be described in more detail below. First, two signal lines are branched from the output request signal line. A stationary filter 22 is interposed in one of the lines to remove noise included in the output request signal. The signal from which noise has been removed by the stationary filter 22 is compared with the signal from which noise has not been removed, and the deviation thereof is calculated. Then, the deviation is determined by the determination unit 23.
Is input to the control unit, and it is determined whether the absolute value exceeds the threshold value. Then, if it is determined that the threshold is exceeded,
The determination unit 23 outputs a signal having a value of 1. On the contrary,
When it is determined that the threshold value is not exceeded, the determination unit 23 outputs a signal having a value of 0.

As described above, since the value of the output signal from the noise removal line 2b is 0 or 1, the value of the signal of the noise removal line 2b is 0 in the signal of the manipulated variable calculation line 2a multiplied by this signal. When, the value becomes 0, and as a result, the feedforward manipulated variable becomes zero. Therefore, even if the output request signal fluctuates due to noise, the feedforward control means 2 does not output an erroneous operation amount. Further, as a matter of course, when a true output change request is made, the value of the output of the noise removal line 2b is 1, so that the operation amount corresponding to the change request is output as the feedforward operation amount.

The feedforward control means 2 is
Specifically, for example, it can be configured by storing a program corresponding to a microcomputer.

As described above, in this embodiment, the fuel flow rate is controlled by the feedforward control while preventing unnecessary fluctuations in the output due to surging, blowout, and noise, so the output is changed. The fuel supply amount can be quickly increased or decreased in response to a request, and the engine output responsiveness can be improved.

Although the present invention has been described above based on the embodiments, the present invention is not limited to the embodiments and various modifications can be made within the scope of the present invention. For example, the relationship between the output request signal and the fuel flow rate may be held in the form of a function instead of the form of a table.

[0023]

As described above, according to the present invention, the fuel supply amount is not controlled in response to the output change request while preventing unnecessary fluctuation of the output due to surging, blowout, and noise. As a result, the excellent effect that the engine output response can be improved can be obtained. Therefore, in the turboshaft engine, it is possible to reduce the change in the rotational speed with respect to a sudden change in the load, and in the turbofan engine, it is possible to increase the response speed of the thrust.

[Brief description of drawings]

FIG. 1 is a block diagram of a control device used in a gas turbine control method of the present invention.

FIG. 2 is a schematic diagram of a feedforward control means of the control device.

FIG. 3 is a graph of a relationship between an output and an engine speed used in a conventional gas turbine control method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Acceleration control means 2 Feedforward control means 2a Manipulation amount calculation line 2b Noise removal line 21 Fuel flow rate table 22 Steady state filter 23 Judgment part 3 Deceleration control means 4 Low level selection means 5 High level selection means

Claims (2)

[Claims] 1. A gas turbine control method in which a fuel supply amount is controlled by an arithmetic processing unit through acceleration control for preventing surging and deceleration control for preventing blowout, and an output request signal When there is a change, a procedure for determining whether or not there is a true output change request according to the change width, and when it is determined to be a true output change request signal, correspond to the output change request signal. A procedure for generating a manipulated variable related to the fuel supply amount, a procedure for comparing the manipulated variable and a manipulated variable by acceleration control, and selecting a lower manipulated variable of the two, and the selected manipulated variable And a manipulated variable by deceleration control are compared with each other, and a higher one of the two is selected and outputted as a fuel flow rate command value. 2. A feedforward control means in a gas turbine control device having acceleration control means for preventing surging, deceleration control means for preventing blowout, low level selection means, and high level selection means. When the output request signal fluctuates, the feedforward control means determines whether there is a true output change request according to the fluctuation range, and determines that there is a true output change request. Then, the operation amount related to the fuel supply amount corresponding to the requested change output is input to the low-order selection unit, and the low-order selection unit causes the low-order operation amount among the operation amounts from the feedforward control unit and the acceleration control unit. Is input to the high level selection means, and the high level selection means selects a high level from the operation amount from the low level selection means and the operation amount from the deceleration control means. Control device for a gas turbine, characterized in that selects and outputs things as the fuel flow rate command value.