Power circuit

• US 5,528,123 A
• Filed: 10/15/1991
• Issued: 06/18/1996
• Est. Priority Date: 10/15/1991
• Status: Expired due to Term

• Current Assignee: Siemens Medical Solutions USA Incorporated (Siemens AG)
• Original Assignee: Acuson Corporation (Siemens AG)
• Inventors: Hutchison, James B.
• Primary Examiner(s): Wong, Peter S.
• Assistant Examiner(s): BERHANE, ADOLF D
• Application Number:
  US07/775,465
• Time in Patent Office: 1,708 Days
• Field of Search: 323/267, 323/207, 323/205, 323/210, 363/44-48, 363/89, 363/126, 363/146, 307/31
• US Class Current: 323/205
• CPC Class Codes: G05F 1/70 Regulating power factor; Regulating reactive current or power
• CPC Class Codes: H02J 3/36 Arrangements for transfer of electric power between ac networks via a high-tension dc link
• CPC Class Codes: H02M 1/4225 using a non-isolated boost converter
• 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
• CPC Class Codes: Y02E 60/60 Arrangements for transfer of electric power between AC networks or generators via a high voltage DC link [HVCD]

Abstract

This invention measures the total line current in a power cord which is used to energize both a power factor corrected system and non-power factor corrected AC loads. The power factor control loop of the power factor corrected system is then driven to correct the power factor of total line current in the power cord ideally to approach unity.

Claims

1. A power circuit for supplying power-factor-controlled electrical energy concomitantly to AC and DC loads, comprising:

an AC power cord having a pair of conductors,

means connected in parallel with said AC power cord to provide an AC output,

means connected in parallel with said AC power cord for correcting the power factor therein and having a DC output,

current-sensing means connected to said AC power cord for sensing total line current, and

means responsive to said current-sensing means for applying to said power-factor-correcting means a corrective signal based upon said sensed total line current, whereby the power factor of the current in said AC power cord is corrected with respect to both said AC and DC loads.

2. The power circuit of claim 1, said power-factor-correcting means being connected in a system that comprises a DC power supply and one or more DC loads.

3. The power circuit of claim 1, said power-factor-correcting means being controlled to maintain (a) an AC line current having a power factor that approaches unity.