Multi-stage compressor system, control device, malfunction determination method, and program

Patent metadata

Field	Value
Publication number	US-10746182-B2
Application number	US-201515314377-A
Country	US
Kind code	B2
Filing date	Jun 22, 2015
Priority date	Jul 1, 2014
Publication date	Aug 18, 2020
Grant date	Aug 18, 2020

Abstract

A multi-stage compressor system is a system of a multi-stage compressor in which compressors are connected in series in a plurality of stages includes a control unit. The control unit determines whether a malfunction is present in the system by comparing a suction flow rate of a first-stage compressor measured by a first sensor with a downstream flow rate from an outlet of the multi-stage compressor measured by a second sensor.

First claim

What is claimed is:

1. A system of a multi-stage compressor in which compressors are connected in series in a plurality of stages, the multi-stage compressor system comprising:
a control unit configured to determine whether a malfunction is present in the system by comparing a suction flow rate of a first-stage compressor measured by a first sensor with a downstream flow rate from an outlet of the multi-stage compressor measured by a second sensor, and
a blowoff valve disposed at a downstream side of the multi-stage compressor,
wherein the control unit determines that the malfunction is present when a measurement value of the first sensor and a measurement value of the second sensor are not the same within a predetermined error range, and
the control unit is configured to open the blowoff valve in a case that the malfunction is present.

2. The multi-stage compressor system according to claim 1 ,
wherein the multi-stage compressor includes a pair of first-stage compressors and subsequent-stage compressors, wherein the subsequent-stage compressors serially connected to the first-stage compressors compress fluids compressed by the pair of first-stage compressors.

3. The multi-stage compressor system according to claim 2 , wherein a measurement value of each of the first sensor and the second sensor is corrected according to at least one of a temperature of a fluid, a pressure of the fluid, and a molecular weight of the fluid in which the first sensor and the second sensor measure.

4. The multi-stage compressor system according to claim 1 , wherein a measurement value of each of the first sensor and the second sensor is corrected according to at least one of a temperature of a fluid, a pressure of the fluid, and a molecular weight of the fluid in which the first sensor and the second sensor measure.

5. The multi-stage compressor system according to claim 4 ,
wherein a pressure of a fluid is measured at an upstream side of the first sensor and a temperature of the fluid is measured at a downstream side of the first sensor.

6. A control device for a multi-stage compressor in which compressors are connected in series in a plurality of stages, the control device comprising:
a control unit configured to determine whether a malfunction is present in the system by comparing a suction flow rate of a first-stage compressor measured by a first sensor with a downstream flow rate from an outlet of the multi-stage compressor measured by a second sensor and determining that the malfunction is present when a measurement value of the first sensor and a measurement value of the second sensor are not the same within a predetermined error range, and
the control unit is configured to open a blowoff valve which is disposed at a downstream side of the multi-stage compressor in a case that the malfunction is present.

7. The control device according to claim 6 , wherein a measurement value of each of the first sensor and the second sensor is corrected according to at least one of a measured temperature of a fluid, a measured pressure of the fluid, and a measured molecular weight of the fluid around the sensor.

8. A malfunction determination method for use in a system of a multi-stage compressor in which compressors are connected in series in a plurality of stages, the malfunction determination method comprising:
determining, by a control unit, whether a malfunction is present in the system by comparing a suction flow rate of a first-stage compressor measured by a first sensor with a downstream flow rate from an outlet of the multi-stage compressor measured by a second sensor, and determining that the malfunction is present when a measurement value of the first sensor and a measurement value of the second sensor are not the same within a predetermined error range, and
opening a blowoff valve which is disposed at a downstream side of the multi-stage compressor in a case that the malfunction is present.

9. The malfunction determination method according to claim 8 , wherein the multi-stage compressor includes a pair of first-stage compressors and sub sequent-stage compressors, wherein the subsequent-stage compressors serially connected to the first-stage compressors compress fluids compressed by the pair of first-stage compressors.

10. The malfunction determination method according to claim 8 , wherein a measurement value of each of the first sensor and the second sensor is corrected according to at least one of a temperature of a fluid, a pressure of the fluid, and a molecular weight of the fluid in which the first sensor and the second sensor measure.

11. The malfunction determination method according to claim 10 ,
wherein a pressure of a fluid is measured at an upstream side of the first sensor and a temperature of the fluid is measured at a downstream side of the first sensor.

12. A non-transitory computer readable medium storing a program configured to cause a computer of a control device for controlling a multi-stage compressor in which compressors are connected in series in a plurality of stages to function as:
a control means configured to determine whether a malfunction is present in the system by comparing a suction flow rate of a first-stage compressor measured by a first sensor with a downstream flow rate from an outlet of the multi-stage compressor measured by a second sensor, and the control means being configured to determine that the malfunction is present when a measurement value of the first sensor and a measurement value of the second sensor are not the same within a predetermined error range, and the control means being configured to open a blowoff valve which is disposed at a downstream side of the multi-stage compressor in a case that the malfunction is present.

13. The non-transitory computer readable medium storing the program according to claim 12 , wherein the program causes the computer to function as:
a means configured to correct a measurement value of each of the first sensor and the second sensor according to at least one of a measured temperature of a fluid, a measured pressure of the fluid, and a measured molecular weight of the fluid around the sensor.

Assignees

• Mitsubishi Heavy Ind Compressor Corp

Inventors

• Nakagawa Yosuke
• Yonemura Naoto
• Miyata Hiroyuki
• Mori Naoki

Classifications

• F04B49/106

  Responsive to pumped volume · CPC title

• F04B49/06

  Control using electricity (regulating by means of floats actuating electric switches F04B49/04) · CPC title

• F04B25/00 Primary

  Multi-stage pumps · CPC title

• F04D27/001 Primary

  Testing thereof; Determination or simulation of flow characteristics; Stall or surge detection, e.g. condition monitoring · CPC title

• F04B49/10

  Other safety measures · CPC title