JPS61189132A - Operation for power facility - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention has a power generation facility in which a power purchasing system is directly connected to a turbine and a generator, and a blower power generation facility in which a turbine, a generator and a blower are connected. Regarding the operation method of electric power equipment connected to private power generation equipment, in more detail, power is supplied from the power purchase system to the generator of the blower power generation equipment, and while the generator is being used as a motor to drive the blower, the power purchase Even in the event of an abnormality such as an accident or breakdown in the system, the power can prevent damage to the turbine without overloading it, and can ensure the minimum amount of air supplied to the destination of the blower. This is a proposal for how to operate the equipment.

[Prior art]

At the steelworks, power is supplied from the power purchase system (hereinafter referred to as the power purchase system) to operate the general loads and important safety loads within the plant, but due to an abnormality, power supply from the power purchase system has become impossible. In some cases, in-house power generation equipment should be installed to ensure power supply to critical safety loads.

That is, as shown in Fig. 2, the general load 11a and the important safety load fib within the plant are connected to the power purchasing system 13, as well as the main power line from the blower power generation equipment A and multiple power generation equipment B (only one is shown in the drawing). Power is supplied via I2.

The blower power generation equipment A uses steam generated in boilers 171 and 171 and sent through steam pipes 172 to power a turbine 173.
a, a generator 174a connected to this, and a blower 175
By driving a, power is supplied to the general load 11a1 and important safety load 11b via the branch line 12a and the main line 12, and air is blown to the blast furnace 19. Further, the power generation equipment B similarly supplies power to the general load 11a2 and the important safety load 11b via the branch line 12b by driving the turbine 173b and the power generation IQ 1174a.

In such power equipment, if an abnormality occurs in the power purchasing system 13 and the power supply frequency of the main line 12 drops below a predetermined value, the frequency relay 14 connected to the main line 12 will detect this and activate the circuit breaker. 15 is opened to disconnect the power purchasing system 13 from the main line 12, and the circuit breaker 16 is opened to disconnect the general load 11a from the main line 12.

As a result, power is supplied to the important safety load 11b by the private power generation equipment.

By the way, in such power equipment, the boiler 171,
The amount of steam generated in 171 is small, and as a result the turbine l
73a is small and the output force of the turbine 173a, that is, the generator 174a and the blower 175a is large, power is supplied from the power purchase system 13 to the generator 174a via the branch line 12a in order to maintain the air blowing to the blast furnace 19. And the power generation t
The Jl 1174a is made to function as an electric motor for driving the blower 175a.

In such a case, if an abnormality occurs in the power purchasing system 13,
As mentioned above, since the power purchasing line I3 is disconnected from the main line 12, the power generation equipment B transfers the electric power for the motor load to the branch line 1.
Power will be supplied to the generator 174a via 2a,
In this case, the amount of power supplied to the important safety load 11b will be reduced by the amount of this load, and there is a possibility that the power supply to the important safety load 11b cannot be ensured. Therefore, in order to prevent such a situation, the frequency relay 14 is connected to the relay circuit 1.
Circuit breaker 187 connected to the middle of branch line 12a via 86
A predetermined signal is issued to open the circuit, and the blower power generation equipment A is disconnected from the main line 12.

Then, the turbine 173a input is 131175 air blowers.
The output of the turbine 173a decreases instantaneously compared to the output of the turbine 173a.
becomes overloaded, and the rotational speed of the generator 174a and the blower 175a connected thereto decreases, and there is a possibility that it will not be possible to blow enough air to maintain blast furnace operation.

In such a case, the stator blade control device 184 connected to the blower 175a operates to adjust the variable angle of the stator blade of the blower 175a in order to restore the output of the blower 175a. become. As a result, although air can be supplied to the blast furnace 19, the input to the turbine 173a is still lower than the output from the blower 175a. Then, from the relay circuit 186, the turbine 173a
A speed regulator 188 for regulating the speed of the turbine 173
A command signal is issued to ensure the insufficient input of a, and upon receiving this command signal, the speed regulator 188 adjusts the steam control valve 1.
89 and increases the input to the turbine 173a.

[Problem that the invention seeks to solve]

However, when the speed control device 188 is operated and the steam control valve 189 is suddenly opened as described above, excessive steam will suddenly flow into the inlet side of the turbine 173a. Thus, the output of the turbine 173a is maintained constant by the operation of the stator vane control device 184 described above.

As a result, there is a problem in that an excessive load is suddenly applied to the turbine 173a, which may cause damage to the turbine 173a.

The surging prevention controller 179 shown in the figure is used to adjust the opening degree of the air blower valve 175a provided on the outlet side of the air blower 175a by WX in order to prevent surging from occurring in the air blower 175a.

Therefore, in order to prevent such damage to the turbine 173a, Japanese Patent Laid-Open No. 59-21238 discloses a method in which the steam control valve 189 is fully closed to stop the turbine 173a under the above operating conditions. ing. According to this method, air is blown to the blast furnace 19 by a blower from another system installed in the private power generation equipment similar to the above, but there is a risk that in some cases it may not be possible to secure the amount of air blown necessary for blast furnace operation. Ta.

[Means for solving problems]

The present invention has been made in view of the above circumstances, and it supplies power from a power purchasing system to a generator of a blower power generation equipment provided in private power generation equipment, and uses the generator as an electric motor to drive a blower connected to the generator. If an abnormality occurs in the power purchasing system, disconnect the power purchasing system from the in-house power generating equipment, fix the angle of the stator blades of the blower, and reduce the opening of the windbreak valve provided on the outlet side. By adjusting the value to a value that can secure the required amount of air to a preset destination, it is possible to prevent damage to the turbine without overloading it, and to ensure that the amount of air sent to the destination is always maintained. The purpose is to provide a method for operating power equipment that can

The method of operating such a power facility according to the present invention is a power facility in which a power purchasing system is connected to a private power generation facility having a power generation facility in which a turbine and a generator are directly connected, and a blower power generation facility in which a turbine, a generator, and an air blower are connected. In the operating method described above, if an abnormality occurs in the power purchasing system while power is being supplied to the generator of the blower power generation equipment from the power purchasing system and the generator is being used as a motor for driving the blower, the power purchasing system shall be replaced. A blowoff valve is provided on the outlet side in order to control the electric power to disconnect and fix the angle of the variable stator blade of the blower, and to ensure a predetermined required amount of air to be supplied to the destination. It is characterized by adjusting the opening degree.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below based on drawings showing embodiments thereof. FIG. 1 is a schematic diagram showing the implementation state of the method for operating power equipment according to the present invention.

General load 1a in the steelworks! : Power is supplied to the important safety load 1b from the power purchasing system 3 via the main line 2, and a blower power generation facility A and a plurality of power generation facilities B are connected to branch lines 2aJb connected to the main line 2, respectively. (1 in the drawing)
Power is supplied from a private power generation facility consisting of (only the base shown).

A frequency relay 4 is connected in the middle of the main line 2.

The frequency relay 4 detects when an abnormality occurs in the power purchasing system 3, making it impossible to feed power to the main line 2 and the power supply frequency drops below a predetermined value, and transmits the power from the power purchasing system 3 to the frequency relay. The circuit breaker 5 connected between the frequency relay 4 and the general load la is opened to disconnect the power purchasing system 3 from the main line 2, and the circuit breaker 6 connected between the frequency relay 4 and the general load la is opened and the general load 1a is disconnected. Disconnect from main line 2. Therefore, if an abnormality occurs in the power purchasing system 3, power will be supplied from the private power generation equipment to the important safety load 1b.

Next, details of the private power generation equipment will be explained. The blower power generation equipment A includes an output shaft (not shown) of a turbine 73a that is driven by steam generated in a plurality of boilers 71, 71 (two are shown in the drawing) and sent through a steam pipe 72. ) is connected to the generator 74.
a and the air blower tJII 75a, driving the generator 74a and the air blower Ia 75a, and the branch line 2a to which the generated power of the generator 74a was connected, and the circuit breaker 87. The air is applied to the general load 1a and the important safety load 1h via the main line 2, and is also blown to the blast furnace 9 via the air pipe 76 from the blower 75a. A blowoff pipe 77 is branched off at a position near the entrance side of the blowpipe 76, and a blowoff valve 78 is interposed in the blowoff pipe 77.

The blowoff valve 78 is for adjusting the amount of air (or blowing pressure) blown into the blast furnace 9 from the blower 75a, and the adjustment is based on the valve opening from the blowoff valve opening setting circuit 79, which will be described below. This is done by adjusting the opening degree of the air blowing valve 78 using a command signal. A flow meter 80 is located near the outlet side of the blast pipe 76. A pressure gauge 81 is interposed in each case. The flow meter 80 detects the amount of air blown into the blast furnace 9, and the pressure gauge 81 detects the outlet pressure of the blower 75a. Flowmeter 80. The detection results of the pressure needles 81 are respectively given to the air discharge valve opening degree setting circuit 79. The air discharge valve opening setting circuit 79 is connected to a flow meter 80. Based on the rain detection signal from the pressure gauge 81, the opening degree of the blast valve 78 is calculated to ensure the minimum required air volume (or pressure) for blast furnace operation, which has been determined in advance through experiments and actual results. The switching circuit 82. sets the valve opening degree of the valve 78 to the calculated value. A valve opening command signal is issued to the ventilation valve 78 via the surging prevention controller 83. This ensures the minimum required air volume (or pressure) for blast furnace operation.

In addition, the blower 7 is variable in order to adjust the amount of air blown.
The stator blade angle of the stator blade 5a is controlled to a predetermined angle by a stator blade control device 84, and a speed adjustment device is installed on the inlet side of the turbine 73a to recover the rotation speed when the rotation speed changes. The device 88 is connected.

Similarly, power generation equipment B drives a turbine 73b with steam sent through boilers 71, 71 and steam pipes 72, and the power generated by a generator 74b directly connected to the turbine 73b is used for general loads 1a and important safety loads. 1b.

In addition, in such a power system, the amount of steam generated in the boiler 71゜71 is small and the input to the turbine 73a does not reach a predetermined level, the generator 74a loses its generating power, and the air blower vIA 75a is driven. If the required power cannot be obtained and there is no abnormality in the power purchase system 3,
Power is supplied to the generator 74a from the power purchasing system 3 via the branch line 2a, and in this case, the power generation 11
1174a functions as an electric motor for driving the blower 75a.

Now, in the power system as described above, an operation method when an abnormality occurs in the power purchasing system 3 while the generator 74a is functioning as an electric motor as described above will be described. When the frequency relay 4 detects that an abnormality has occurred in the power purchase system 3, it opens the circuit breakers 5 and 6 as described above, disconnects the power purchase system 3 from the main line 2, and connects the general load 1a to the main line 2. At the same time, a cutoff command signal is issued to the relay circuit 86.

The relay circuit 86 connects the circuit breaker 87 of the branch line 2a to the generator 74a.
In the power supply direction of the branch line 2a, that is, power is supplied from the power purchasing system 3 to the generator 74a and the generator 74a functions as a motor, or the generator 74a functions as a generator and is connected to the main line 2. It is possible to detect whether or not power is being supplied, and when the generator 74a receives the cutoff command signal while functioning as an electric motor, it opens the circuit breaker 87 and disconnects the blower power generation equipment A from the main line 2. Separate more. Further, the switching circuit 82 is closed and the switching circuit 85 is opened. Then, a predetermined valve opening command signal is issued from the blow-off valve opening setting circuit 79 to the blow-off valve 78, and as a result, the minimum required air flow rate (or pressure) from the blower 75a to the blast furnace 9 is ensured. That will happen.

On the other hand, no operational output is given from the stator vane control device 84 to the blower 75a, and as a result, the stator vane angle remains fixed.

[Effect]

In the case of the present invention as described above, if an accident or failure occurs in the power purchase system 3 while the generator 74a to the blower power generation equipment is functioning as a motor, the frequency relay 4 is operated and the power purchase system 3 and the general Negative (@ 1 disconnect a from main line 2,
Furthermore, by activating the relay circuit 86, the blower power generation equipment A is disconnected from the main line 2, and power is supplied to the important safety load lb only by the power generation equipment B, so that the following effects are achieved. That is, if the blower power generation equipment A is not disconnected from the main line 2 when the generator 74a is functioning as an electric motor, the power generation equipment B is connected to the generator 74a.
However, according to the present invention, the power supplied to the important safety load 1b may be reduced, and the power supply to the important safety load 1b may not be satisfied. There is no such possibility.

In addition to the above-mentioned operation, the present invention also cuts off the operational output of the stator vane control device 84, and further adjusts the valve opening of the blast valve 78 to ensure the minimum amount of air (or pressure) required for blast furnace operation. Therefore, it also has the following effects.

That is, when the generator 74a functions as an electric motor, the relationship shown in the following equation (l) is established between the input Lt of the turbine 73a, the input LL11 of the electric motor, and the output Lb of the blower 75a.

Lb-Lm+Lt...(1)
Then, when the power supply to the generator 74a is stopped, Lm-0 is reached, and Lb>Lt momentarily becomes. Therefore, turbine 7
3a becomes overloaded, and the rotational speed of the blower 75a decreases. In such a case, if the operation input to the stator vane control device 84 is not cut off as in the conventional case, the stator vane control device 84 will decrease due to the decrease in the rotation speed of the blower 75a, and the control target ( The angle of the stationary blade is adjusted to return the inlet air volume Qi, outlet air volume 00, or outlet pressure Po of the blower 75a to the target values, thereby preventing a decrease in the output of the air blower 1175a. Therefore, the turbine 73a is still in an overloaded state and its rotational speed is further reduced. If this happens, the speed control device 88 will operate as described in the conventional method, and the steam control valve 89 will be suddenly opened, which may cause a sudden load to be applied to the turbine 73a, resulting in damage to the turbine 73a. However, in the present invention, the operating output of the stator vane control device 84 is cut off to fix the angle of the stator blades of the blower 75a, and the blowoff valve 78 is opened in order to prevent overloading of the turbine 73a in this state. The air flow rate (or pressure) of the blower 75a is increased by a predetermined amount.

This prevents overloading of the turbine 73a and prevents its rotational speed from decreasing, so in the case of the present invention, the speed control device 88 does not operate, so that a sudden load is not applied to the turbine 73a and it is damaged. There is no risk that this will lead to In addition, the opening degree of the blast valve 78 in this case is set to a value that can secure the minimum amount of air (or pressure) necessary for blast furnace operation, so the present invention is different from the conventional method described above. Unlike other methods, blast furnace operation can be maintained at all times.

〔effect〕

As detailed above, the method of operating power equipment according to the present invention includes:
When power is supplied from the power purchasing system to the generator installed in the blower power generation equipment, and the generator is being used as a motor to drive the blower, an abnormality occurs in the power purchasing system and the power supply is stopped. The angle of the blades is fixed, and the opening of the blow-off valve provided on the outlet side of the blower is increased, and the value is set to a value that can maintain blast furnace operation, so it does not cause overload on the turbine. The present invention has excellent effects such as there is no risk of damage to the blast furnace, and blast furnace operation can be maintained at all times.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing the implementation state of the present invention, and FIG. 2 is a schematic diagram showing the implementation state of the conventional method.

Claims (1)

[Scope of Claims] 1. A method of operating power equipment in which a power purchasing system is connected to a private power generation equipment having a power generation equipment directly connected to a turbine and a generator, and a blower power generation equipment connected to a turbine, a generator, and an air blower. In this case, if an abnormality occurs in the power purchasing system while power is being supplied from the power purchasing system to the generator of the blower power generation equipment and the generator is being used as a motor for driving the blower, the power purchasing system is disconnected, and , while controlling the variable stator blade angle of the blower to be fixed, the opening degree of the blowoff valve provided on the outlet side is controlled to ensure a predetermined required amount of air supplied to the destination. A method of operating electric power equipment characterized by adjusting.