Patent EP0486875A2 successfully refreshed from Google Patents.
EP0486875A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Power supply controlled to supply load current formed as sine wave
Assignee: Hitachi Ltd
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Filing: 1991-11-06
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Granted: —
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Expires: 2011-11-06
Abstract
Abstract A power supply basically includes a rectifying section (10) for rectifying a sinusoidal a.c. voltage, a switching section (11) for receiving a voltage output from the rectifying section, and a smoothing section (12) having a smoothing capacitor. The power supply is controlled to have a sinusoidal load current and for the purpose, includes as a feature a power source circuit having a first path for flowing current from the rectifying section to the smoothing section and a second path for flowing current from an inductor (15) of the switching section to the smoothing section, circuits (16, 17) for sensing the current flowing through the first path and forming a reference current with a target waveform based on the sensed current, circuits (18, 19, 20) for sensing the current flowing through the switching element and determining such a conduction ratio of the switching element as matching the waveform of the sensed current to the waveform of the reference current, and a control circuit (21) for sequentially controlling a plurality of switching elements connected in parallel on and off based on the determined conduction ratio.
Inventors
- 👤 Yasutsugu Kawaguchi
- 👤 Makoto Ishii
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 14:43
CPC Classifications
H; H02; H02M; H02M1/00; H02M1/42; H02M1/4208; H02M1/4225; G; G05; G05F; G05F1/00; G05F1/70; H02M3/00; H02M3/02; H02M3/04; H02M3/10; H02M3/145; H02M3/155; H02M3/156; H02M3/158; H02M7/00; H02M7/02; H02M7/04; H02M7/12; H02M7/21; H02M1/4233; Y; Y02; Y02B; Y02B70/00; Y02B70/10
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
246 words
In a power supply including a rectifying section (10) for rectifying a sinusoidal a.c. voltage, a switching section (11) for supplying an output voltage of said rectifying section, and a smoothing section (12) having a smoothing capacitor, said switching section having an inductor and a switching element, said inductor storing energy from current output from said rectifying section during an on-state period of said switching element and emitting said energy to said smoothing section during an off-state period of said switching element, said power supply having a capability of controlling load current to have a sinusoidal wave-form comprising: (1) a first path for flowing current from said rectifying section to said smoothing section; (2) a second path for flowing current from said inductor to said smoothing section; (3) first current sensing means (15) for sensing the current (I c2 ) flowing through said first path; (4) current waveform forming means (16, 17) for forming a reference current having a target object from the current output from said first current sensing means; (5) second current sensing means (14) for sensing current flowing through said switching element; (6) means (18, 19, 20) for determining such a conduction ratio of said switching element as matching a waveform of an output current of said second current sensing means to a waveform of said reference current during a period when said reference current flows; and (7) means (21) for controlling said switching element on and off based on said conduction ratio.
Claim 2
Dependent Claim
32 words
A power supply according to claim 1, wherein said means for forming a current waveform includes a high-pass filter (16) having a higher cut-off frequency than the frequency of said a.c. voltage.
Claim 3
Dependent Claim
29 words
A power supply according to claim 1, further comprising means (22) for setting both amplification factors of said first and second current sensing means to have a predetermined relation.
Claim 4
Dependent Claim
29 words
A power supply according to claim 2, further comprising means (22) for setting both amplification factors of said first and second current sensing means to have a predetermined relation.
Claim 5
Dependent Claim
47 words
A power supply according to claim 1, wherein said switching section (11) includes a plurality of switching elements (Tr₁, Tr₂, Tr₃) connected in parallel and said means for controlling said switching section on and off includes means (11) for switching sequentially said switching elements on and off.
Claim 6
Dependent Claim
21 words
A power supply according to claim 5, wherein said switching elements are accommodated as one chip or module in a package.
Claim 7
Dependent Claim
214 words
In a power supply including a rectifying section (10) for rectifying a sinusoidal a.c. voltage, a switching section (11) for supplying an output voltage of said rectifying section, and a smoothing section (12) having a smoothing capacitor, said switching section having an inductor and a switching element, said inductor storing energy from current output from said rectifying section during an on-state period of said switching element and emitting said energy to said smoothing section during an off-state period of said switching element, said power supply (Fig. 5) having a capability of controlling load current to have a sinusoidal waveform comprising: (1) means (14) for sensing current flowing from said rectifying to said smoothing section; (2) current waveform forming means (23, 24) for forming a sinusoidal reference current having an amplitude defined according to an average value of the output current of said current sensing means and a frequency equal to said a.c. voltage; (3) means (18, 19, 20) for determining such a conduction ratio of said switching element as matching a waveform of an output current of said second current sensing means to a waveform of said reference current during a period when said reference current flows; and (4) means (21) for controlling said switching element on and off based on said conduction ratio.
Claim 8
Dependent Claim
42 words
A power supply according to claim 7, wherein said switching section includes a plurality of switching elements connected in parallel and said means for controlling said switching section on and off includes means for switching sequentially said switching elements on and off.
Claim 9
Dependent Claim
21 words
A power supply according to claim 8, wherein said switching elements are accommodated as one chip or module in a package.
Claim 10
Dependent Claim
132 words
In a power supply including a rectifying section (10) for rectifying a sinusoidal a.c. voltage, a switching section (11) for supplying an output voltage of said rectifying section, and a smoothing section (12) having a smoothing capacitor, said switching section having an inductor and a switching element, said inductor storing energy from current output from said rectifying section during an on-state period of said switching element and emitting said energy to said smoothing section during an off-state period of said switching element, said power supply (Figs. 4 and 8) having a capability of controlling load current to have a sinusoidal waveform comprising: (1) a first path for flowing current from said rectifying section to said smoothing section; and (2) a second path for flowing current from said inductor to said smoothing section.
Claim 11
Dependent Claim
31 words
A power supply according to claim 10, wherein said switching section includes: said plurality of switching elements connected in parallel; and means for sequentially controlling said switching elements on and off.
Claim 12
Dependent Claim
21 words
A power supply according to claim 11, wherein said switching elements are accommodated as one chip or module in a package.
Claim 13
Dependent Claim
143 words
In a power supply including rectifying sections (D₁, D₂, D₃, D₄), a switching section for receiving the output voltage of said rectifying sections, and a smoothing section having a smoothing capacitor (4), said power supply having a capability of controlling a load current to have a sinusoidal waveform and said switching section being located between said rectifying section and said smoothing section, said switching section comprising: (1) a circuit having two or more series circuits each composed of inductors (25a, 25b) and switching elements (T a , T b ), said series circuits being connected in parallel; (2) rectifier elements (D 19a , D 19b ) connected to contacts between said inductors and said switching elements; (3) a current path for supplying energy to said smoothing section through said rectifier elements; and (4) means (101) for controlling said switching elements on and off.
Claim 14
Dependent Claim
30 words
A power supply according to claim 13, wherein said means for controlling said switching elements on and off includes means (101) for sequentially controlling said switching elements on and off.
Claim 15
Dependent Claim
183 words
In a power supply including voltage double rectifying sections (D₁₁, D₁₃) for rectifying a sinusoidal a.c. voltage, a switching section for receiving the output voltage of said voltage doubler rectifying section and a smoothing section having smoothing capacitors (4A, 4B), said power supply (Fig. 12) having a capability of controlling a load current to have a sinusoidal waveform and said switching section being located between said voltage double rectifying sections and said smoothing section, said switching section comprising: (1) a circuit having two series circuits each composed of an inductor (28a, 28b), a first rectifier element (D 22a , D 22b ) and a switching element (T a , T b ), said two series circuits being connected to an a.c. voltage generator (1) in parallel; (2) a current path for supplying energy from a later stage of said inductors to said smoothing section through second rectifier elements (D 21a , D 21b ); and (3) means (101) for controlling said switching element on and off if the output voltage of said rectifying section is equal to or lower than a predetermined value.
Claim 16
Dependent Claim
30 words
A power supply according to claim 15, wherein said means for controlling said switching element on and off includes means (101) for sequentially controlling said switching elements on and off.
Claim 17
Dependent Claim
136 words
In a power supply including a rectifying section (10) for rectifying a sinusoidal a.c. voltage, a switching section (11) for receiving a voltage output from said rectifying section (10), and a smoothing section (12) having a smoothing capacitor, said switching section having an inductor and switching elements (T a , T b ), said inductor storing energy from the output current of said rectifying section during an on-state period of said switching element and emitting said stored energy to said smoothing section during an off-state period of said switching elements, said power supply (Fig. 6) having a capability of controlling a load current to have a sinusoidal waveform and said switching section comprising: (1) a plurality of said switching elements (T a , T b ); and (2) means (101) for sequentially controlling said switching elements.
References Cited (Backward Citations)
No citation records indexed.
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