Multi-voltage transformer

• US 6,404,653 B1
• Filed: 10/26/2000
• Issued: 06/11/2002
• Est. Priority Date: 10/26/1999
• Status: Expired due to Term

• Current Assignee: Antec Corp (CommScope Holding Company, Inc.)
• Original Assignee: Antec Corp (CommScope Holding Company, Inc.)
• Inventors: Goodroe, Joey, Chitsazan, Ehsan, Batson, John Gary
• Primary Examiner(s): Vu, Bao Q.
• Application Number:
  US09/697,652
• Time in Patent Office: 593 Days
• Field of Search: 307/65, 307/66, 307/72-75, 307/150, 363/16, 363/41, 363/95, 363/97, 363/131
• US Class Current: 363/16
• CPC Class Codes: H02J 9/062 for AC powered loads
• CPC Class Codes: H02J 9/067 using multi-primary transformers, e.g. transformer having one primary for each AC energy source and a secondary for the loads
• 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 7/53806 in a push-pull configuration of the parallel type

Abstract

A multi-voltage transformer includes an average current loop circuit, a pulse width generator, a push-pull driver, and a pulse width modulator coupled to the average current loop circuit, the pulse width generator, and the push-pull driver for generating pulses for driving a power supply. In a standard operating mode, the power supply is powered by an AC power source. The power supply uses the AC power source to drive the output of the power supply and to recharge the batteries associated with the power supply. When the power supply is operating on AC power, it translates the AC sinusoidal wave signal into a saw tooth wave signal that drives a pulse width modulator. When the AC power source is interrupted, the transformer switches the power source from the AC power source to a battery backup source. The transformer is designed to operate with a variety of battery voltages. The transformer monitors the voltage and current loads on the power supply and determines a duty cycle setting that will meet the demands of the system. An exemplary embodiment described herein operates with either 36 volt batteries or 48 volt batteries.

Claims

1. A method of operating an uninterruptible power supply having a primary power source, a secondary battery power source, and an inverter having an inverter duty cycle, the method comprising:

monitoring a power supply voltage load on the uninterruptible power supply;

monitoring a power supply current load on the uninterruptible power supply;

determining a primary power supply excitation waveform based on the power supply voltage load and the power supply current load;

inputting a secondary battery power source input having a secondary battery power source voltage;

determining an inverter duty cycle setting that will produce a battery excitation waveform that is substantially equivalent to said primary power supply excitation waveform when the power supply is energized by the secondary battery power source having the secondary battery power source voltage; and

adjusting the inverter duty cycle of the uninterruptible power supply to the determined inverter duty cycle setting;

thereby enabling the uninterruptible power supply to operate using the secondary battery power source having the secondary battery power source voltage to produce a battery power supply excitation waveform substantially similar to said primary power supply excitation waveform.

3. The power supply device of claim 1, wherein the transformer is a ferro-resonant transformer.

4. The power supply device of claim 3, wherein the voltage sources include 36 volt and 48 volt batteries.

5. The power supply device of claim 3, wherein the pulse width modulator generates two square wave pulse waves.

6. The power supply device of claim 5, wherein the two square wave pulse waves are 180 degrees out of phase from one another.

7. The power supply device of claim 6, wherein the square wave pulse waves have a variable duty cycle.

2. An uninterruptible power supply device comprising:

an inverter;

an average battery current input for inputting an average battery current;

a primary power source input for inputting a primary power source having a primary power source waveform;

a secondary battery power source having a secondary battery power source voltage;

a pulse width generator for generating a first pulse waveform having a first pulse duty cycle;

an average current loop circuit for modifying the length of the first pulse duty cycle to form a second pulse duty cycle based at least in part on the average battery current;

a pulse width modulator coupled to the average current loop circuit and the pulse width generator for generating a second pulse waveform having said second pulse duty cycle; and

said inverter utilizing said second pulse waveform in conjunction with said secondary battery power source to produce an output waveform substantially equivalent to the primary power source waveform;

thereby enabling the uninterruptible power supply device to operate using a plurality of secondary power sources having different secondary battery power source voltages.

8. A method of operating an uninterruptible power supply having a primary and a secondary power source, and an inverter circuit;

the method comprising;

monitoring a current load on the primary power souce of the uninterruptible power supply to determine a desired output waveform;

generating a duty cycle correlated to said desired output waveform;

inputting a secondary power source having a secondary power source voltage; and

utilizing said duty cycle in connection with said secondary power source to produce said desired output waveform independent from the secondary power source voltage;

thereby enabling the uninterruptible power supply to operate using a plurality of secondary power sources having different secondary power source voltages.

9. The method of claim 8, wherein said secondary power source is a battery.