Multiphase power supply with series connected power cells with failed cell bypass

• US 6,222,284 B1
• Filed: 10/06/1999
• Issued: 04/24/2001
• Est. Priority Date: 05/21/1998
• Status: Expired due to Fees

• Current Assignee: Siemens Energy & Automation Incorporated (Siemens AG)
• Original Assignee: Robicon Corp. (Siemens AG)
• Inventors: Aiello, Marc F., Hammond, Peter W.
• Primary Examiner(s): Ballato, Josie
• Assistant Examiner(s): RIOS CUEVAS, ROBERTO JOSE
• Application Number:
  US09/413,563
• Time in Patent Office: 566 Days
• Field of Search: 200/1.R, 200/43.16, 200/290, 200/318, 200/323, 307/125, 307/142, 307/144, 307/54, 307/71, 320/120, 320/122
• US Class Current: 307/125
• CPC Class Codes: B60L 15/007 Physical arrangements or structures of drive train converters specially adapted for the propulsion motors of electric vehicles
• CPC Class Codes: H02M 1/325 with means for allowing continuous operation despite a fault, i.e. fault tolerant converters
• CPC Class Codes: H02M 7/49 Combination of the output voltage waveforms of a plurality of converters
• CPC Class Codes: Y02T 10/64 Electric machine technologies in electromobility

Abstract

A high output level is maintained in power supplies having multiple cells in each leg. Failed cells in any leg are bypassed to provide a current path through the respective leg. All of the unfailed cells are utilized while maintaining equal magnitude between phases and a balance phase relationship in the line-to-line output voltage. The invention may be utilized in conjunction with a peak voltage reduction circuit, and a by-pass switch.

Claims

1. A transfer switch for interconnecting a plurality of cells in the output of a multiphase power supply said transfer switch comprising:

(a) a single pole double throw switch assembly having a movable switch arm;

(b) a force member urging said switch arm into a first switch position;

(c) a latch member holding said switch arm in a second switch position; and

(d) a pneumatically operated latch release whereby pneumatic fluid activates said transfer switch to release said latch when said switch arm is in said second position and permit said force member to transfer said switch arm to said first position.

2. The transfer switch of claim 1 further comprising:

(e) a source of pressurized fluid located remotely from said switch assembly; and

(f) said source of pressurized fluid connected to said latch release by a tube of non-electrically conducting material.

3. The transfer switch of claim 2 further including:

(g) means for manually moving said switch arm from said first position to said second position against the urging of said force member.

4. A variable output device comprising:

a. a plurality of power cells connected in electrical series to provide an output;

b. at least one transfer switch for selectively interconnecting one of said plurality of cells in a series arrangement and selectively shunting an output of one of a series of failed cells;

c. said at least one transfer switch including a single pole double throw bypass switch;

d. said bypass switch connected to break connection to said failed power cell before creating a shunt path around said power cell;

e. a switch arm movable between an open position and a closed position, said closed position creating said shunt path between said output terminals;

f. a force member urging said switch arm in said closed position;

g. a latch member holding said switch arm in said open position; and

h. a latch release device, said latch release device releasing said latch member such that said force member moves said switch arm to said closed position, said latch release device releasing said latch member responsive to said detecting said failed cell.

5. The variable output device of claim 4 wherein said force member comprises a spring member and said latch release device comprises one of a mechanical, pneumatic, hydraulic, electric, electronic, magnetic, and electromagnetic device.