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US Patent 6545887 - Unified constant-frequency integration control of three-phase power factor corrected rectifiers, active power filters and grid-connected inverters
US Patent Issued on April 8, 2003
Estimated Patent Expiration Date:
August 10, 2021Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
Estimated Patent Expiration Date:
August 10, 2021Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.AbstractAn unified constant-frequency integration (UCI) control method based on one-cycle control employs an integrator with reset as its core component along with a few logic and linear components to control the pulse width of a three-phase recitifier, active power filter, or grid-connected inverter so that the all three phase current draw from or the current output to the utility line is sinusoidal. No multipliers and reference calculation circuitry are needed for controlling active power filters. The UCI control employs constant switching frequency and operates in continuous conduction mode (CCM). If in some cases a DSP is desired for some other purposes, the Unified Constant-frequency Control function can be realized by a low cost DSP with a high reliability, because no high speed calcutation, high speed A/D converter, and mutipliers are required. | InventorsApplicationNo. 928005 filed on 08/10/2001US Classes:363/89, With transistor control means in the line circuit363/44, In rectifier systems363/47, With low pass L or LC filter363/84For rectifier systemField of Search363/89, With transistor control means in the line circuit363/44, In rectifier systems363/47, With low pass L or LC filter363/39, With means to introduce or eliminate frequency components363/84, For rectifier system363/90With inductive control means in the line circuitExaminersPrimary: Vu, Bao Q.Attorney, Agent or FirmUS Patent References5436550, AC-DC converter having saw-tooth wave generating circuit in active filterIssued on: 07/25/1995 Inventor: Arakawa5561595, Power inverter with input line conditioning Issued on: 10/01/1996 Inventor: Smith6011707, Switching-type DC power source apparatus Issued on: 01/04/2000 Inventor: Mine6014001, Method for powering an electronically switched variable reluctance motor, and power supply circuit therefor Issued on: 01/11/2000 Inventor: Guinet6049179, High-pressure discharge lamp lighting apparatus Issued on: 04/11/2000 Inventor: Kisaichi, et al.6177739Electric power source for equipment having power saving mode, power saving control device and image forming apparatus having the power source Issued on: 01/23/2001 Inventor: Matsudaira, et al. International ClassesH02M 001/12H02M 007/68 H02M 007/04 |
