Method for regulating the rotational speed of a compressor as a function of the available gas flow of a source and regulation thereby applied

Patent metadata

Field	Value
Publication number	US-10815997-B2
Application number	US-201615755273-A
Country	US
Kind code	B2
Filing date	Aug 11, 2016
Priority date	Aug 31, 2015
Publication date	Oct 27, 2020
Grant date	Oct 27, 2020

Abstract

A method for controlling the speed of a compressor with a controller as a function of the available gas flow. The method includes the steps of setting a desired value for the inlet pressure; determining the inlet pressure; and determining the speed. The method further includes controlling the speed of the compressor by reducing or increasing it depending on whether the inlet pressure is less than or greater than a set desired value until the inlet pressure is equal to the set desired value where the characteristic data of the compressor relating to the efficiency and/or the Specific Energy Requirement (SER) as a function of the speed and the inlet pressure is provided and the desired value of the inlet pressure is adjusted on the basis of the aforementioned characteristic data so that the efficiency of the compressor is a maximum or the SER is a minimum.

First claim

The invention claimed is:

1. A controller for controlling a speed of a compressor as a function of an available flow of gas originating from a source, comprising:
an input for a signal that is representative of an inlet pressure at an inlet of the compressor;
an input for a signal that is representative of the speed of the compressor;
a desired value to be set for the inlet pressure, and,
wherein the controller is configured to control the speed of the compressor by reducing the speed when the inlet pressure is less than the set desired value of the inlet pressure, or by increasing the speed when the inlet pressure is greater than the set desired value of the inlet pressure until the inlet pressure is equal to the set desired value,
wherein the controller further comprises:
a memory in which a characteristic data of the compressor are stored or can be stored that relate to an efficiency and/or a specific energy requirement of the compressor, which is a ratio of a power supplied to the compressor to a compressed gas flow supplied, as a function of the speed and the inlet pressure; and,
wherein the controller is further configured to calculate an adjusted desired value of the inlet pressure to adjust the set desired value, the adjusted desired value corresponding to a maximum of an efficiency of the compressor or to a minimum of a specific energy requirement after the control of the speed at the adjusted desired value of the inlet pressure.

2. The controller according to claim 1 , wherein the controller is further configured to automatically determine the characteristic data of the compressor during a use of the compressor and to store them point by point in the memory of the controller.

3. The controller according to claim 2 , wherein it is provided with an additional input for a signal that is representative of the power supplied to the compressor, whereby this signal is used by the controller to determine the efficiency and/or the specific energy requirement and to store or overwrite them in the memory with the characteristic data as a function of the speed and the inlet pressure.

4. The controller according to claim 1 , wherein it is provided with a program to get the compressor to operate successively at different operating points in an operating region of the compressor by setting the corresponding desired value of the inlet pressure and the speed for each operating point in incremental steps.

5. A compressor comprising the controller according to claim 1 .

6. The compressor according to claim 5 , wherein the compressor is configured to supply gas originating from a source with a variable available flow to supply an entire available flow of gas from the source to a downstream network of consumers with the highest possible efficiency and/or the lowest possible specific energy requirement, which is the ratio of the power supplied to the compressor to the compressed gas flow supplied.

7. A method for controlling a speed of a compressor as a function of an available gas flow originating from a source, whereby the compressor is provided with a controller for controlling the speed, comprising the following steps:
setting of a desired value for an inlet pressure at an inlet of the compressor;
determining the inlet pressure at the inlet of the compressor;
determining the speed of the compressor;
controlling the speed of the compressor by reducing the speed when the inlet pressure is less than the set desired value of the inlet pressure, or by increasing the speed when the inlet pressure is greater than the set desired value of the inlet pressure until the inlet pressure is equal to the set desired value;
storing a characteristic data of the compressor relating to an efficiency and/or a specific energy requirement onto a memory of the controller, wherein the specific energy requirement is a ratio of a power supplied to the compressor to a compressed gas flow supplied, as a function of the speed and the inlet pressure;
calculating an adjusted desired value of the inlet pressure to adjust the set desired value, said adjusted desired value corresponding to a maximum of an efficiency of the compressor or to a minimum of a specific energy requirement after the control of the speed at the adjusted desired value of the inlet pressure.

8. The method according to claim 7 , wherein the characteristic data of the compressor are determined beforehand and entered in the memory of the controller.

9. The method according to claim 7 , wherein the characteristic data of the compressor are automatically determined during the use of the compressor and are stored in the memory of the controller.

10. The method according to claim 9 , wherein to determine the characteristic data of the compressor during the use of the compressor, the efficiency and/or the specific energy requirement is determined for successive steady operating points and stored in the memory as a function of the speed and the inlet pressure.

11. The method according to claim 10 , wherein to determine the efficiency and/or the specific energy requirement, the flow of compressed gas and the power supplied to the compressor to drive the compressor are determined.

12. The method according to claim 9 , wherein at least during a commissioning of the compressor, the characteristic data of the compressor are determined over an entire operating region of the compressor and are stored in the memory.

13. The method according to claim 12 , wherein to determine the characteristic data of the compressor over the entire operating region of the compressor, the controller is provided with a program to get the compressor to operate successively at different operating points within the operating region by setting the corresponding desired value of the inlet pressure and the speed for each operating point, according to incremental steps.

14. The method according to claim 7 , wherein it is applied to a screw compressor.

15. The method according to claim 7 , wherein it is applied to a supply of gas originating from a source with a variable available flow, in order to be able to supply an entire available flow of gas from the source to a downstream network of users with the highest possible efficiency and/or with the lowest possible specific energy requirement.

16. The method according to claim 7 , further comprising a step of adjusting the set desired value of the inlet pressure.

Assignees

• Atlas Copco Airpower Nv

Inventors

• Patwardhan Subodh Sharadchandra
• Magits Hans Theo

Classifications

• F04C2270/051

  Controlled or regulated · CPC title

• F04C2270/18

  Pressure · CPC title

• F04C2270/025

  Controlled or regulated · CPC title

• F04C2270/60

  Prime mover parameters · CPC title

• F04C2270/0525

  Controlled or regulated · CPC title