Patent US4625272A successfully refreshed from Google Patents.
US4625272A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Converter control apparatus and method
Assignee: Hitachi Ltd
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Filing: 1983-06-17
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Granted: 1986-11-25
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Expires: 2003-06-17
Abstract
Abstract The input terminals of a PWM converter are connected to the a-c power supply via a reactor. A capacitor C as well as a load 11 are connected to the d-c output terminals of the PWM converter. An apparent phase of the power supply voltage E is shifted depending upon the difference between a d-c voltage detected across both terminals of the capacitor and a set voltage, and a control signal for the PWM converter is prepared, with the shifted voltage as a reference. When the detected voltage is greater than the set voltage, the PWM converter is so controlled as to be operated with a lagging power factor, and the a-c voltage at the input terminals of the PWM converter becomes smaller than the power supply voltage. Accordingly, the d-c voltage can be maintained at a value smaller than the set voltage.
Inventors
- 👤 Toshiaki Okuyama
- 👤 Yuzuru Kubota
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 07:15
CPC Classifications
H; H02; H02M; H02M7/00; H02M7/02; H02M7/04; H02M7/12; H02M7/145; H02M7/155; H02M7/1555; H02M7/1557
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
185 words
A power-supply apparatus comprising: a PWM converter for converting an a-c power supply voltage into a d-c voltage; a capacitor connected across the d-c output terminals of said PWM converter; a load connected across the d-c output terminals of said PWM converter; a voltage comparator for comparing a setpoint value of said d-c voltage with a detected value of said d-c voltage and for producing a voltage deviation signal in accordance therewith, said PWM converter being controlled in accordance with said voltage deviation signal; a voltage detector for detecting said a-c power supply voltage; a phase shifter for shifting the phase of an a-c power supply voltage signal detected by said voltage detector toward the advancing side or the lagging side depending upon the polarity of said voltage deviation signal; a current instruction circuit for multiplying said a-c power supply voltage signal having the phase thereof shifted by said phase shifter by said voltage deviation signal so as to produce a current instruction signal; and a firing control circuit for controlling the firing operation of said PWM converter in dependence upon said current instruction signal.
Claim 2
Dependent Claim
185 words
A power-supply apparatus comprising: a PWM converter for converting an a-c power supply voltage into a d-c voltage; a capacitor connected across the d-c output terminals of said PWM converter; a load connected across the d-c output terminals of said PWM converter; a voltage comparator for comparing a setpoint value of said d-c voltage with a detected value of said d-c voltage and for producing a voltage deviation signal in accordance therewith, said PWM converter being controlled in accordance with said voltage deviation signal; a voltage detector for detecting said a-c power supply voltage; a phase shifter for shifting the phase of an a-c power supply voltage signal detected by said voltage detector toward the advancing side or the lagging side depending upon the polarity of said voltage deviation signal; a current instruction circuit for multiplying said a-c power supply voltage signal having the phase thereof shifted by said phase shifter by said voltage deviation signal so as to produce a current instruction signal; and a firing control circuit for controlling the firing operation of said PWM converter in dependence upon said current instruction signal.
Claim 3
Dependent Claim
22 words
A power-supply apparatus according to claim 1, wherein said phase shifter shifts the a-c power supply voltage signal by a predetermined angle.
Claim 4
Dependent Claim
31 words
A power-supply apparatus according to claim 1, wherein said phase shifter changes the phase-shifting angle for the a-c power supply voltage signal depending upon the magnitude of said voltage deviation signal.
Claim 5
Dependent Claim
231 words
A power-supply apparatus comprising: a PWM converter for converting an a-c power supply voltage into a d-c voltage; a capacitor connected across the d-c output terminals of said PWM converter; a load connected across the d-c output terminals of said PWM converter; a voltage comparator for comparing a setpoint value of said d-c voltage with a detected value of said d-c voltage and for producing a voltage deviation signal in accordance therewith, said PWM converter being controlled in accordance with said voltage deviation signal; reactive current instruction means for producing a reactive-component control signal for instructing the magnitude of a reactive component in an a-c input current flowing into said PWM converter; a transformer for detecting said a-c power supply voltage and for producing a first voltage having the same phase as said a-c power supply voltage and a second voltage having a phase different by 90° from said a-c power supply voltage; current instruction means for multiplying said first voltage by said voltage deviation signal to obtain an active-component instruction signal, said current instruction means multiplying said second voltage by said reactive-component control signal to obtain a reactive-component instruction signal, said current instruction means adding said active-component instruction signal and said reactive-component instruction signal for producing a current instruction signal; and firing control means for controlling the firing operation of said PWM converter in dependence upon said current instruction signal.
Claim 6
Dependent Claim
231 words
A power-supply apparatus comprising: a PWM converter for converting an a-c power supply voltage into a d-c voltage; a capacitor connected across the d-c output terminals of said PWM converter; a load connected across the d-c output terminals of said PWM converter; a voltage comparator for comparing a setpoint value of said d-c voltage with a detected value of said d-c voltage and for producing a voltage deviation signal in accordance therewith, said PWM converter being controlled in accordance with said voltage deviation signal; reactive current instruction means for producing a reactive-component control signal for instructing the magnitude of a reactive component in an a-c input current flowing into said PWM converter; a transformer for detecting said a-c power supply voltage and for producing a first voltage having the same phase as said a-c power supply voltage and a second voltage having a phase different by 90° from said a-c power supply voltage; current instruction means for multiplying said first voltage by said voltage deviation signal to obtain an active-component instruction signal, said current instruction means multiplying said second voltage by said reactive-component control signal to obtain a reactive-component instruction signal, said current instruction means adding said active-component instruction signal and said reactive-component instruction signal for producing a current instruction signal; and firing control means for controlling the firing operation of said PWM converter in dependence upon said current instruction signal.
Claim 7
Dependent Claim
48 words
A power-supply apparatus according to claim 4, wherein said reactive current instruction means includes means for comparing a setpoint value of an a-c input voltage of said PWM converter with a detected value thereof and for producing a voltage deviation signal therebetween as a reactive component control signal.
Claim 8
Independent Claim
170 words
A method of controlling a PWM converter of a power-supply apparatus including a PWM converter for converting an a-c power supply voltage into a d-c voltage, a capacitor connected across the d-c output terminals of the PWM converter, and a load connected across the d-c output terminals of the PWM converter, the method comprising the steps of: comparing a setpoint value of the d-c voltage with a detected vale of the d-c voltage and for producing a voltage deviation signal in accordance therewith; controlling the PWM converter in accordance with the voltage deviation signal; detecting the a-c power supply voltage; shifting the phase of the detected a-c power supply voltage signal toward the advancing side of the lagging side depending upon the polarity of the voltage deviation signal; multiplying the a-c power supply voltage signal which has the phase thereof shifted by the voltage deviation signal so as to produce a current instruction signal; and controlling the firing operation of the PWM converter in dependence upon the current instruction signal.
Claim 9
Independent Claim
170 words
A method of controlling a PWM converter of a power-supply apparatus including a PWM converter for converting an a-c power supply voltage into a d-c voltage, a capacitor connected across the d-c output terminals of the PWM converter, and a load connected across the d-c output terminals of the PWM converter, the method comprising the steps of: comparing a setpoint value of the d-c voltage with a detected vale of the d-c voltage and for producing a voltage deviation signal in accordance therewith; controlling the PWM converter in accordance with the voltage deviation signal; detecting the a-c power supply voltage; shifting the phase of the detected a-c power supply voltage signal toward the advancing side of the lagging side depending upon the polarity of the voltage deviation signal; multiplying the a-c power supply voltage signal which has the phase thereof shifted by the voltage deviation signal so as to produce a current instruction signal; and controlling the firing operation of the PWM converter in dependence upon the current instruction signal.
Claim 10
Dependent Claim
28 words
a method according to claim 6, wherein the step of shifting the phase of the a-c power supply voltage signal includes shifting the phase by a predetermined angle.
Claim 11
Dependent Claim
41 words
A method according to claim 6, wherein the step of shifting the phase of the a-c power supply voltage signal includes changing the phase-shifting angle for the a-c power supply voltage signal depending upon the magnitude of the voltage deviation signal.
Claim 12
Independent Claim
216 words
A method for controlling the PWM converter of a power-supply apparatus including a PWM converter for converting an a-c power supply voltage into a d-c voltage, a capacitor connected across the d-c output terminals of the PWM converter, and a load connected across the d-c output terminals of the PWM converter, the method comprising the steps of: comparing a setpoint value of the d-c voltage with a detected value of the d-c voltage and producing a voltage deviation signal in accordance therewith; controlling the PWM converter in accordance with the voltage deviation signals; producing a reactive-component control signal for instructing the magnitude of the reactive component in an a-c input current flowing into the PWM converter; detecting the a-c power supply voltage and producing a first voltage having the same phase as the a-c power supply voltage and a second voltage having a phase different by 90° from the a-c power supply voltage; multiplying the first voltage by the voltage deviation signal to obtain an active-component instruction signal; multiplying the second voltage by the reactive-component control signal to obtain a reactive component instruction signal; adding the active-component instruction signal and the reactive-component instruction singal to produce a current instruction signal; and controlling the firing operation of the PWM converter in dependence upon the current instruction signal.
Claim 13
Independent Claim
216 words
A method for controlling the PWM converter of a power-supply apparatus including a PWM converter for converting an a-c power supply voltage into a d-c voltage, a capacitor connected across the d-c output terminals of the PWM converter, and a load connected across the d-c output terminals of the PWM converter, the method comprising the steps of: comparing a setpoint value of the d-c voltage with a detected value of the d-c voltage and producing a voltage deviation signal in accordance therewith; controlling the PWM converter in accordance with the voltage deviation signals; producing a reactive-component control signal for instructing the magnitude of the reactive component in an a-c input current flowing into the PWM converter; detecting the a-c power supply voltage and producing a first voltage having the same phase as the a-c power supply voltage and a second voltage having a phase different by 90° from the a-c power supply voltage; multiplying the first voltage by the voltage deviation signal to obtain an active-component instruction signal; multiplying the second voltage by the reactive-component control signal to obtain a reactive component instruction signal; adding the active-component instruction signal and the reactive-component instruction singal to produce a current instruction signal; and controlling the firing operation of the PWM converter in dependence upon the current instruction signal.
Claim 14
Dependent Claim
46 words
A method according to claim 9, wherein the step of producing a reactive-component control signal includes comparing a setpoint value of an a-c input voltage of the PWM converter with a detected value and producing the voltage voltage deviation signal therebetween as the reactive-component control signal.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-11-24 | 1990-05-26 | 1990-11-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-11-24 | 1994-05-26 | 1994-11-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-11-24 | 1998-05-26 | 1998-11-25 | $7700.00 | Window Closed / Lapsed |