Controller for compressor

Patent metadata

Field	Value
Publication number	US-11530858-B2
Application number	US-201716089962-A
Country	US
Kind code	B2
Filing date	Apr 11, 2017
Priority date	Apr 12, 2016
Publication date	Dec 20, 2022
Grant date	Dec 20, 2022

Abstract

A controller for a compressor, more specifically for a first electrical VSD motor configured to drive a compressor element, the controller including a housing in which is provided a rectifier, a DC link with a DC bus and two inverters connected to the same DC bus, a first inverter configured to control the first VSD motor driving the compressor element, and a second inverter configured to control a second VSD motor driving a fan configured to cool the compressor.

First claim

The invention claimed is:

1. A compressor comprising:
a controller connected to a first Variable Speed Drive (VSD) motor for driving a compressor element of said compressor,
wherein the controller is further connected to a second VSD motor for driving a cooling fan configured to cool said compressor,
said controller comprising a housing for all elements protected from an outside environment in which is provided a rectifier, a Direct Current (DC) link with a DC bus and two inverters connected to the same DC bus, a first inverter configured to control a frequency and a voltage of the first VSD motor driving said compressor element, and a second inverter configured to control a frequency and a voltage of the second VSD motor driving the fan, wherein said control varies the speed of the second VSD motor,
wherein the controller further comprises a voltage sensor positioned on the DC bus that measures a voltage of the first VSD motor and/or of the second VSD motor,
wherein the controller is configured to stop the compressor when the measured voltage is equal to or higher than a predetermined voltage limit or when the measured voltage is equal to or lower than a predetermined minimum voltage,
wherein a DC link capacitor is connected between the rectifier and the first and second inverters, and
wherein the compressor is a compressed gas compressor comprising an inlet for receiving ambient air and a compressed gas outlet.

2. The compressor according to claim 1 , wherein said compressor does not have a relay cabinet.

3. The compressor according to claim 1 , wherein each of said inverters comprises at least one Insulated-Gate Bipolar Transistor (IGBT) which is connected to said DC bus.

4. The compressor according to claim 1 , wherein the controller further comprises a separate cooling fan for cooling power electronics of said controller.

5. The compressor according to claim 1 , wherein the controller further comprises a first current sensor for sensing current going through a winding of the first VSD motor.

6. The compressor according to claim 5 , wherein the controller further comprises a second current sensor for sensing current going through a winding of the second VSD motor.

7. The compressor according to claim 6 , wherein the controller further comprises an electrical protection to overcurrent.

8. The compressor according to claim 1 , wherein the controller further comprises a communication link to a temperature sensor, said temperature sensor being at the first VSD motor driving the compressor element.

9. The compressor according to claim 1 , wherein the controller further comprises an internal power supply.

10. The compressor according to claim 1 , wherein the rectifier, the DC link with the DC bus and the two inverters are on one Printed Circuit Board.

11. The compressor according to claim 1 , further comprising an ambient humidity sensor, wherein if a measured humidity is above a humidity limit, the controller maintains the first VSD motor and/or the second VSD motor at a high temperature so that condensate cannot form.

12. The compressor according to claim 1 , wherein the compressed gas outlet is connected to a compressed gas user network.

13. The compressor according to claim 1 , wherein the controller receives data concerning a requirement of a compressed gas.

14. A controller adapted to be connected to a first Variable Speed Drive (VSD) motor for driving a compressor element of a compressor or for driving a vacuum pump, and said controller is further adapted to be connected to a second VSD motor for driving a cooling fan configured to cool said compressor or said vacuum pump,
said controller comprising a housing for all elements protected from an outside environment in which is provided a rectifier, a Direct Current (DC) link with a DC bus and two inverters connected to the same DC bus, a first inverter configured to control a frequency and a voltage of the first VSD motor driving, and a second inverter configured to control a frequency and a voltage of the second VSD motor, wherein said control varies the speed of the second VSD motor,
wherein the controller further comprises a voltage sensor positioned on the DC bus that measures a first voltage of the first VSD motor and a second voltage of the second VSD motor,
wherein the controller is configured to stop the compressor or vacuum pump when the measured voltage is equal to or higher than a predetermined voltage limit or when the measured voltage is equal to or lower than a predetermined minimum voltage,
wherein a DC link capacitor is connected between the rectifier and the first and second inverters, and
wherein the compressor is a compressed gas compressor comprising an inlet for receiving ambient air and a compressed gas outlet or the vacuum pump comprises an inlet for receiving ambient air.

15. The controller according to claim 14 , wherein said controller is further configured to generate an alert when the measured voltage is compared to an additional limit.

Assignees

• Atlas Copco Airpower Nv

Inventors

• Cools Pieter Michel Mena
• Krishnasing Yogesh Avinash

Classifications

• F04C2240/808

  Electronic circuits (e.g. inverters) installed inside the machine · CPC title

• F04C28/08 Primary

  characterised by varying the rotational speed · CPC title

• F25B2600/021

  Inverters therefor · CPC title

• F04C29/04

  Heating; Cooling (of machines or engines in general F01P); Heat insulation (heat insulation in general F16L59/00) · CPC title

• F04C23/001 Primary

  of similar working principle · CPC title