SINGLE PHASE OPERATION OF A THREE-PHASE DRIVE SYSTEM

• US 20140035492A1
• Filed: 07/31/2012
• Published: 02/06/2014
• Est. Priority Date: 07/31/2012
• Status: Active Grant

• Current Assignee: Rockwell Automation Technologies Incorporated (Allen-Bradley Co., Inc.)
• Original Assignee: Rockwell Automation Technologies Incorporated (Allen-Bradley Co., Inc.)
• Inventors: Ahmed, Ahmed Mohamed Sayed, Wei, Lixiang, Seibel, Brian J.
• Granted Patent: US 8,988,026 B2
• Time in Patent Office: Days
• US Class Current: 318/400.3
• CPC Class Codes: H02M 1/10 Arrangements incorporating converting means for enabling loads to be operated at will from different kinds of power supplies, e.g. from ac or dc
• CPC Class Codes: H02M 1/325 with means for allowing continuous operation despite a fault, i.e. fault tolerant converters
• CPC Class Codes: H02M 5/4585 having a rectifier with controlled elements
• CPC Class Codes: H02M 7/2195 the switches being synchronously commutated at the same frequency of the AC input voltage
• CPC Class Codes: H02P 27/06 using dc to ac converters or inverters H02P27/05 takes precedence
• CPC Class Codes: Y02B 70/10 Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Abstract

Single-phase voltage operation techniques are provided for a three-phase drive system. A drive system may include a rectifier configured to couple to a three-phase AC voltage source. The rectifier may be configured to convert AC voltage from the three-phase AC voltage source to a direct current (DC) voltage. The drive system may also include a controller configured to send a plurality of switching signals to a plurality of switches in the rectifier such that the plurality of switching signals minimizes a current provided to the rectifier when only a single-phase of the three-phase AC voltage source is available.

Claims

1. A drive system, comprising:

a rectifier configured to couple to a three-phase alternating current (AC) voltage source, wherein the rectifier is configured to convert AC voltage from the three-phase AC voltage source to a direct current (DC) voltage; and

a controller configured to send a plurality of switching signals to a plurality of switches in the rectifier, wherein the plurality of switching signals are configured to minimize a current provided to the rectifier when only a single phase of the three-phase AC voltage source is available.

2. The drive system of claim 1, comprising an inverter configured to couple to the rectifier and configured to invert the DC voltage into a three-phase AC voltage.

3. The drive system of claim 2, comprising a motor configured to couple to the inverter, wherein the motor is configured to drive a load using the three-phase AC voltage.

4. The drive system of claim 1, wherein the rectifier is a fundamental front end (FFE) rectifier.

5. The drive system of claim 4, wherein the FFE rectifier is configured to return regenerative braking energy from a motor to the three-phase AC voltage source.

6. The drive system of claim 1, wherein the plurality of switches comprise a plurality of insulated gate bipolar transistors (IGBTs).

7. The drive system of claim 1, wherein the plurality of switches correspond to switches disposed on two of three legs of the rectifier.

8. The drive system of claim 1, wherein the controller is configured to send the plurality of switching signals by:

determining a plurality of firing angles for the plurality of switches;

determining a plurality of conduction angles for the plurality of switches, wherein the plurality of firing angles and the plurality of conduction angles are configured to minimize the current provided to the rectifier; and

sending the plurality of firing angles and the plurality of conduction angles to the plurality of switches.

9. The drive system of claim 8, wherein the plurality of firing angles and the plurality of conduction angles are configured to keep a motor in the drive system operating when only the single phase of the three-phase AC voltage source is available.

10. The drive system of claim 8, wherein the plurality of firing angles and the plurality of conduction angles are determined based on:

11. The drive system of claim 1, wherein the controller is configured to send the plurality of switching signals by:

receiving one or more system parameters associated with the drive system; and

generating the plurality of switching signals based at least in part on the system parameters; and

sending the generated plurality of switching signals to the plurality of switches.

12. The drive system of claim 11, wherein the system parameters comprise an inductance value that corresponds to the rectifier.

13. The drive system of claim 11, wherein the system parameters comprise one or more trip settings that correspond to one or more protective devices in the drive system, an operating voltage range of a motor in the drive system, or any combination thereof

14. A system, comprising:

a six-pulse fundamental front end (FFE) rectifier configured to convert a single-phase alternating current (AC) voltage from a single-phase AC source to direct current (DC) power applied to a DC bus; and

a controller configured to send a plurality of switching signals to a plurality of switches in the six-pulse FFE rectifier, wherein the plurality of switching signals is configured to minimize a current provided to the six-pulse FFE rectifier from the single-phase AC source and minimize a DC current ripple output by the six-pulse FFE rectifier.

15. The system of claim 14, wherein a portion of the plurality of switching signals is configured to close a first switch during a positive peak of the single-phase AC voltage and close a second switch during a negative peak of the single-phase AC voltage, wherein the first switch is disposed on a positive side of the six-pulse FFE rectifier and the second switch is disposed on a negative side of the six-pulse FFE rectifier.

16. The system of claim 15, wherein the first switch is disposed on a first leg of the six-pulse FFE rectifier and the second switch is disposed on a second leg of the six-pulse FFE rectifier.

17. The system of claim 14, wherein the plurality of switching signals is configured to minimize a DC voltage ripple output by the six-pulse FFE rectifier.

18. A method, comprising:

operating a rectifier of a three-phase motor drive system using a single-phase alternating current (AC) voltage, wherein the rectifier is configured to convert the single-phase AC voltage into a direct current (DC) voltage;

determining a plurality of switching signals for a plurality of switches in the rectifier, wherein the plurality of switching signals is configured keep a motor in the three-phase motor drive system operating using the single-phase AC voltage; and

sending the plurality of switching signals to the plurality of switches.

19. The method of claim 18, wherein the rectifier operates using the single-phase AC voltage when one or two of three phases in a three-phase AC voltage source coupled to the rectifier is unavailable.

20. The method of claim 18, wherein the rectifier operates using the single-phase AC voltage when one or two of three phases in a three-phase AC voltage source coupled to the rectifier has a fault.

21. The method of claim 18, comprising operating the rectifier using a three-phase voltage when a three-phase AC voltage source coupled to the rectifier is available.

22. The method of claim 21, wherein operating the rectifier using the three-phase voltage comprises:

modifying the plurality of switching signals, wherein the modified plurality of switching signals is configured to enable the rectifier to convert the three-phase voltage into the DC voltage; and

sending the modified plurality of switching signals to the plurality of switches.

23. The method of claim 18, wherein the plurality of switching signals is configured to minimize a root-mean-square current input into the rectifier, a DC voltage ripple output by the rectifier, a DC current ripple output by the rectifier, or any combination thereof.

24. A method, comprising:

operating a rectifier of a three-phase motor drive system using a three-phase alternating current (AC) voltage, wherein the rectifier is configured to convert the three-phase AC voltage into a direct current (DC) voltage;

operating the rectifier using a single-phase AC voltage when the three-phase voltage is not available by;

determining a plurality of switching signals for a plurality of switches in the rectifier, wherein the plurality of switching signals is configured keep a motor in the three-phase motor drive system operating using the single-phase AC voltage; and

sending the plurality of switching signals to the plurality of switches.

25. The method of claim 24, wherein the motor operates in a reduced power mode.

26. The method of claim 24, comprising operating the rectifier using the three-phase AC voltage when the three-phase voltage becomes available by:

modifying the plurality of switching signals for the plurality of switches in the rectifier, wherein the modified plurality of switching signals is configured operate the motor in the three-phase motor drive system; and

sending the modified plurality of switching signals to the plurality of switches.