JPH0467212A - Turbine steam pressure controller - Google Patents

Abstract

PURPOSE:To reduce the pressure loss and increase the generated output by obtaining an operation signal from the pressure target value and the detected value of the inlet pressure of a steam turbine and controlling a pressure control valve. CONSTITUTION:In regard of the target value of the steam quantity Q supplied to a turbine generator 2, the steam flow rate signal obtained from the target value PS of a steam tank 1 through a flow rate meter 12 is inputted to a computing element 13. Thus the pressure loss DP is operated. An adder/subtractor 14 subtracts the loss DP from the value PS to obtain the target value SV and inputs this value to a pressure controller 16, together with the turbine steam inlet pressure P2 detected by a pressure gauge 15. Then a pressure control valve 17 is operated in response to an operation signal MV and the steam inlet pressure is controlled at a constant level. Meanwhile a bypass operation valve 7 is operated by the operation signal MV of a pressure controller 6. Then the steam pressure is controlled to a fixed level for the steam quantity Q of a bypass pipeline system 4 so that the steam pressure of the tank 1 is equal to the set value PS of the steam tank pressure.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a turbine steam pressure control device applied to a plant that supplies steam from a boiler or the like to a turbine generator.

(Prior Art) As a conventional turbine steam pressure control device of this type, there is one constructed as shown in FIG. This means that excess steam generated by the boiler is stored in the high-pressure steam reservoir 1,
This steam is formed in parallel with a steam supply system that is supplied to the turbine generator 2 via the steam piping 3 and this steam supply system, and the steam from the steam reservoir 1 is transferred to the turbine generator 2 when the turbine generator 2 fails. A bypass piping system 4 is provided for use as a pickup.

Then, the steam pressure gauge 5 detects the pressure inside the steam reservoir 1, and the steam pressure P1 detected by the steam pressure gauge 5 is adjusted to the steam reservoir pressure set value PS, and the corresponding operation signal M
A first pressure regulator 6 that outputs V, and a bypass piping system 4
The first control system includes a bypass operation valve 7 which is provided in the middle of the pressure regulator 6 and is operated in response to an operation signal MV from the pressure regulator 6, and constitutes a closed loop.

Further, a subtractor 8 that subtracts the steam reservoir pressure set value PS and pressure loss DP, a turbine steam inlet pressure gauge 9 that detects the steam pressure P2 at the turbine inlet in the steam piping 3, and this turbine steam inlet pressure gauge 9 A second pressure regulator 9 inputs the detected steam pressure P2 and the output SV of the subtractor 8 and outputs an operation signal MV, and a A second control system comprising a pressure regulating valve 10 that is operated to an opening degree according to an operation signal MV and forming a closed loop is provided.

Since the first control system is configured in this way, the bypass operation valve 7 is operated by the operation signal MV of the pressure regulator 6, so the amount of steam flowing into the bypass piping system 4 is determined by the steam pressure in the steam reservoir 1. Steam pressure constant control is performed so that the steam reservoir pressure set value PS becomes the steam reservoir pressure setting value PS.

In addition, since the second control system is configured, the pressure control valve 10 is operated by the operation signal MV of the pressure regulator 9, so that the amount of steam flowing into the steam supply system 3 is such that the steam inlet pressure is equal to the steam reservoir pressure. Steam type low pressure constant control is performed so that the set value PS is reached.

(Problems to be Solved by the Invention) In the conventional turbine steam pressure control device described above, the greater the amount of steam generated from the steam reservoir 1, the greater the power generation output of the turbine generator 2.

Further, reducing the pressure loss DP to 0 as much as possible leads to effective utilization of steam. However, in the conventional device, the pressure loss DP is set as a fixed parameter, so even if the steam pressure in the steam reservoir 1 increases, only the same amount of steam is sent to the turbine generator 2.

The present invention provides a turbine steam pressure control device in which the higher the steam pressure in the steam reservoir, the more steam can be sent to the turbine generator, thereby increasing the amount of power generated by the turbine generator. With the goal.

[Configuration of the Invention (Means for Solving the Problems) In order to achieve the above object, the present invention provides a steam supply system that supplies steam from a steam reservoir to a turbine generator via steam piping, and a steam supply system that supplies steam from a steam reservoir to a turbine generator via steam piping. a bypass piping system formed in parallel with the steam reservoir, a steam pressure gauge that detects the pressure in the steam reservoir, and a first pressure that outputs an operation command to adjust the pressure detected by the steam pressure gauge to a pressure set value. a first control system comprising a regulator, a bypass operation valve provided in the bypass piping system and operated in response to an operation signal from the pressure regulator; and a turbine that detects the pressure of the turbine population in the steam piping. a steam inlet pressure gauge, a pressure loss calculator that calculates a pressure loss using a predetermined calculation formula based on the measured value in the steam piping, and a pressure loss calculated by the pressure loss calculator and a pressure setting value of the steam reservoir. a second pressure regulator that inputs the pressure detection value from the steam reservoir turbine steam inlet pressure gauge and outputs an operation signal to adjust it to the pressure target value from the computing unit; and a second control system comprising a pressure regulating valve provided in the steam piping and operated in response to an operation signal from the second pressure regulator.

(Operation) According to the present invention, the pressure loss is calculated using a predetermined calculation formula, the pressure target value is determined from this pressure loss and the steam reservoir pressure setting value, and the pressure target value and the steam turbine inlet pressure detection value are combined. An operating signal is obtained from the steam generator, and the pressure regulating valve installed in the steam piping is operated in accordance with this operating signal, so pressure loss can be minimized and steam can be used effectively.
The higher the steam pressure in the steam reservoir, the more steam can be sent to the turbine generator, and the more power the turbine generator generates.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings. FIG. 1 is a system diagram showing a first embodiment of the present invention,
It is the same as the conventional system shown in FIG. 3 described above in that it includes a steam supply system, a bypass piping system, and a first control system, and only the configuration of the second control system is different. In other words, the steam supply system is
Steam from a steam reservoir 1 such as a boiler is supplied to a turbine generator 2 via a steam pipe 3. The bypass piping system is formed in parallel with the steam supply system, and uses steam from the steam reservoir 1 as a backup in the event of a failure of the turbine generator 2.

The control system of j@1 includes a steam pressure gauge 5 that detects the pressure inside the steam reservoir 1, and adjusts the pressure detected by the steam pressure gauge 5 to the steam reservoir pressure set value PS, and performs corresponding operations. It consists of a first pressure regulator 6 that outputs a signal MV, and a bypass operation valve 7 that is provided in the middle of the bypass piping system and is operated according to the operation signal MV from the pressure regulator 6,
It forms a closed loop.

Therefore, the second control system includes a flow meter 12 that detects a steam flow rate signal in the steam pipe 3, and a steam flow rate signal detected by this flow meter 12, and uses, for example, the steam flow rate signal detected by the flow meter 12 to A pressure loss calculator 13 that calculates the pressure loss DP in the pipe 3 and a pressure loss D calculated by the pressure loss calculator 13.
an adder/subtractor 14 that manually calculates a set value Sv between P and the pressure set value PS of the steam reservoir; a turbine steam inlet pressure gauge 15 that detects the pressure at the inlet of the turbine generator 2; and this turbine steam inlet pressure gauge. Turbine steam inlet pressure P2 detected in step 15 and set value SV obtained by the adder/subtractor 14
The second pressure regulating valve 17 inputs and outputs the operating opening degree, forming a closed loop.

Here, the pressure loss DP is determined by the steam flow rate Q flowing into the turbine generator 2 and the constant K1. The following equation holds true between and 2 (where 1 is negative).

DP-Kl ・2 to Q+ ・
... (1) If this equation (1) is expressed in a graph, it will look like Figure 2.

The operation of this embodiment configured as above will be explained. The target value for the amount of steam Q supplied to the turbine generator 2 is determined by inputting the steam flow rate signal obtained by the flow meter 12 to the pressure loss calculator 13 based on the target value PS of the steam reservoir 1, and calculating the following equation (1). Pressure loss DP is calculated based on the formula and FIG.

Then, in the adder/subtractor 14, a target value Sv is obtained by subtracting the pressure loss DP from the pressure target value PS of the steam reservoir 1. This target value Sv is input to the pressure regulator 16, this and the turbine steam inlet pressure P2 detected by the turbine steam inlet pressure gauge 15 are input, and the pressure regulator valve 17 is operated according to the operation signal MV determined here. As a result, steam input pressure is controlled to be constant.

On the other hand, regarding the first control system, as in the conventional device, the bypass operation valve 7 is operated by the operation signal MV of the pressure regulator 6, so the amount of steam flowing into the bypass piping system 4 is equal to the amount of steam in the steam reservoir 1. Steam pressure constant control is performed so that the pressure is equal to the steam reservoir pressure set value PS.

As described above, the steam flow rate signal obtained by the flow meter 12 can be taken as a function of pressure loss DP,
The higher the steam pressure, the more steam can be sent to the turbine generator 2 side, and the more the turbine generator 2 generates electricity.

In the above embodiment, the steam flow rate signal is taken as a function of the pressure loss DP, but any other method may be used as long as the pressure loss can be calculated.

[Effects of the Invention] According to the present invention, the higher the steam pressure in the steam reservoir, the more steam can be sent to the turbine generator, and the turbine generator generates more power. A pressure control device can be provided.

[Brief explanation of the drawing]

Fig. 1 is a system diagram showing an embodiment of the turbine steam pressure control device of the present invention, Fig. 2 is a characteristic diagram of pressure loss and steam flow rate to explain the operation of the computing unit shown in Fig. 1, and Fig. 3 1 is a system diagram showing an example of a conventional turbine steam pressure control device. 1... High pressure steam reservoir, 2... Turbine generator, 3...
...Steam piping, 4...Bypass piping 5...Steam pressure gauge, 6...Pressure regulator, 7...Pressure control valve, 12...
...flow meter, 13...pressure calculator, 14...adder/subtractor, 15...turbine steam inlet pressure gauge, 16...pressure regulator, 17...pressure control valve.

Claims (1)

[Scope of Claims] A steam supply system that supplies steam from a steam reservoir to a turbine generator via steam piping, a bypass piping system formed in parallel to this steam supply system, and a system that controls the pressure in the steam reservoir. a steam pressure gauge to detect; a first pressure regulator that outputs an operation command to adjust the pressure detected by the steam pressure gauge to a pressure set value; and a first pressure regulator installed in the bypass piping system and operated from the pressure regulator. a first control system consisting of a bypass operation valve that is operated in response to a signal; a turbine steam inlet pressure gauge that detects the pressure at the turbine inlet in the steam piping; and a predetermined calculation based on the measured value in the steam piping. a pressure loss calculator that calculates pressure loss using a formula; a calculator that calculates a pressure target value from the pressure loss calculated by the pressure loss calculator and a pressure setting value of the steam reservoir; and a pressure gauge from the steam reservoir turbine steam inlet pressure gauge. a second pressure regulator that inputs a detected pressure value and outputs an operation signal to adjust the detected pressure value to the pressure target value from the computing unit; A turbine steam pressure control device comprising: a second control system comprising a pressure regulating valve operated in response to an operation signal;