US 6,982,499 B1
Power converting method and apparatus
Tadayoshi Kachi, Kariya (Japan); Junichi Takeuchi, Kariya (Japan); and Seiki Sakata, Kariya (Japan)
Assigned to Kabushiki Kaisha Toyoda Jidoshokki Seisakusho, Kariya (Japan)
Filed on Oct. 17, 2000, as Appl. No. 9/690,183.
Claims priority of application No. 11-312402 (JP), filed on Nov. 02, 1999.
Int. Cl. H02J 7/016 (2006.01)
U.S. Cl. 307—75 13 Claims
OG exemplary drawing
 
1. A method of supplying power using a main DC power supply for generating a predetermined voltage to supply a first output voltage substantially equal to the predetermined voltage and a second output voltage lower than the predetermined voltage, comprising the steps of:
connecting a first DC power supply for generating the same voltage as the second output voltage in series to a second DC power supply for generating a differential voltage between the first output voltage and the voltage from the first DC power supply, thereby forming the main DC power supply,
connecting a DC-DC converter to the second DC power supply; and
stepping down the voltage output from the second DC power supply to produce the second output voltage by using the DC-DC converter.