Control device, control method, and system

Patent metadata

Field	Value
Publication number	US-12366174-B2
Application number	US-202218712911-A
Country	US
Kind code	B2
Filing date	Sep 27, 2022
Priority date	Nov 30, 2021
Publication date	Jul 22, 2025
Grant date	Jul 22, 2025

Abstract

This control device comprises: an acquiring unit for acquiring, as a first inlet pressure, a pressure value of first steam on a first inlet side as seen from a first regulating valve of a first turbine that rotates using the first steam, which is supplied from the first inlet via the first regulating valve, and acquiring, as a second inlet pressure, a pressure value of second steam on a second inlet side as seen from a second regulating valve of a second turbine that rotates on the same rotating shaft as the first turbine using the second steam, which is supplied from the second inlet via the second regulating valve; and a control unit for regulating an opening degree of the first regulating valve and an opening degree of the second regulating valve in accordance with the first inlet pressure and the second inlet pressure.

First claim

The invention claimed is:

1. A control device comprising:
an acquisition unit that acquires, when viewed from a first control valve of a first turbine that rotates using first steam supplied from a first inlet via the first control valve, a pressure value of the first steam on a first inlet side as a first inlet pressure, and acquires, when viewed from a second control valve of a second turbine that rotates about a same rotary shaft as the first turbine using second steam supplied from a second inlet via the second control valve, a pressure value of the second steam on a second inlet side as a second inlet pressure; and
a control unit that controls a valve opening degree of the first control valve and a valve opening degree of the second control valve according to the first inlet pressure and the second inlet pressure,
wherein the control unit controls the valve opening degree of the first control valve and the valve opening degree of the second control valve according to the first inlet pressure and the second inlet pressure with reference to a predetermined range with respect to a correspondence relation between the first inlet pressure and the second inlet pressure at which a thrust force applied to the rotary shaft becomes appropriate based on a correspondence relation, and
wherein the control unit controls, in a case where the range is expressed in Cartesian coordinates in which a horizontal axis represents one of the first inlet pressure and the second inlet pressure and a vertical axis represents the other of the first inlet pressure and the second inlet pressure, one of the first control valve and the second control valve so that the one of the first control valve and the second control valve is throttled with reference to an upper boundary line side of the range, and controls the other of the first control valve and the second control valve so that the other of the first control valve and the second control valve is throttled with reference to a lower boundary line side of the range.

2. The control device according to claim 1 ,
wherein the range corresponds to, in a case where one of the first inlet pressure or the second inlet pressure is biased from a combination of the first inlet pressure and the second inlet pressure in which a thrust force by the first turbine and a thrust force by the second turbine are balanced, a region in which the thrust force is equal to or less than a maximum allowable value.

3. The control device according to claim 2 ,
wherein the control unit controls the valve opening degree of the first control valve and the valve opening degree of the second control valve according to the first inlet pressure and the second inlet pressure, using a region obtained by subtracting a predetermined constant from a boundary of the region toward an inside of the region as the range.

4. The control device according to claim 1 ,
wherein the control unit controls the valve opening degree of the first control valve and the valve opening degree of the second control valve according to the first inlet pressure and the second inlet pressure by controlling an upper limit of the valve opening degree of the first control valve and an upper limit of the valve opening degree of the second control valve.

5. The control device according to claim 4 ,
wherein the control unit controls the upper limit of the valve opening degree of the first control valve and the upper limit of the valve opening degree of the second control valve by selectively setting the upper limits of the valve opening degree of the first control valve and the valve opening degree of the second control valve to any of a maximum value of each of the valve opening degrees, each value increased by a predetermined amount from each current value of the first inlet pressure and the second inlet pressure, or each value with reference to the range.

6. A control method comprising:
a step of acquiring, when viewed from a first control valve of a first turbine that rotates using first steam supplied from a first inlet via the first control valve, a pressure value of the first steam on a first inlet side as a first inlet pressure, and acquiring, when viewed from a second control valve of a second turbine that rotates about a same rotary shaft as the first turbine using second steam supplied from a second inlet via the second control valve, a pressure value of the second steam on a second inlet side as a second inlet pressure; and
a step of controlling a valve opening degree of the first control valve and a valve opening degree of the second control valve according to the first inlet pressure and the second inlet pressure,
wherein, in the step of controlling, controlling the valve opening degree of the first control valve and the valve opening degree of the second control valve according to the first inlet pressure and the second inlet pressure with reference to a predetermined range with respect to a correspondence relation between the first inlet pressure and the second inlet pressure at which a thrust force applied to the rotary shaft becomes appropriate based on a correspondence relation, and
wherein, in the step of controlling, controlling, in a case where the range is expressed in Cartesian coordinates in which a horizontal axis represents one of the first inlet pressure and the second inlet pressure and a vertical axis represents the other of the first inlet pressure and the second inlet pressure, one of the first control valve and the second control valve so that the one of the first control valve and the second control valve is throttled with reference to an upper boundary line side of the range, and controlling the other of the first control valve and the second control valve so that the other of the first control valve and the second control valve is throttled with reference to a lower boundary line side of the range.

7. A system comprising:
a first control valve;
a second control valve;
a first turbine that rotates using first steam supplied from a first inlet via the first control valve;
a second turbine that rotates about a same rotary shaft as the first turbine using second steam supplied from a second inlet via the second control valve;
an acquisition unit that acquires, when viewed from the first control valve, a pressure value of the first steam on a first inlet side as a first inlet pressure, and acquires, when viewed from the second control valve, a pressure value of the second steam on a second inlet side as a second inlet pressure; and
a control unit that controls a valve opening degree of the first control valve and a valve opening degree of the second control valve according to the first inlet pressure and the second inlet pressure,
wherein the control unit controls the valve opening degree of the first control valve and the valve opening degree of the second control valve according to the first inlet pressure and the second inlet pressure with reference to a predetermined range with respect to a correspondence relation between the first inlet pressure and the second inlet pressure at which a thrust force applied to the rotary shaft becomes appropriate based on a correspondence relation, and
wherein the control unit controls, in a case where the range is expressed in Cartesian coordinates in which a horizontal axis represents one of the first inlet pressure and the second inlet pressure and a vertical axis represents the other of the first inlet pressure and the second inlet pressure, one of the first control valve and the second control valve so that the one of the first control valve and the second control valve is throttled with reference to an upper boundary line side of the range, and controls the other of the first control valve and the second control valve so that the other of

Assignees

• Mitsubishi Heavy Ind Ltd

Inventors

• Ouchi Toshiaki
• Yamamoto Keisuke
• Nakamura Tateki

Classifications

• F05D2220/72

  a steam turbine · CPC title

• F01K17/04

  for specific purposes other than heating (F01K17/06 takes precedence) · CPC title

• F01D15/00

  Adaptations of machines or engines for special use; Combinations of engines with devices driven thereby · CPC title

• F05D2270/051

  Thrust · CPC title

• F05D2220/31

  in steam turbines · CPC title