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US 6,724,644 B2Granted
AC/DC converter
AssigneeKoninklijke Philips Electronics N.V.
InventorChristoph Loef
Life of this patent
Estimating the term…
Abstract
An AC/DC converter includes a resonance converter (A3) which is suitable, for example, for operation with different AC line voltages from different AC power grids. The AC/DC converter further includes a bridge circuit (A4) drivable as a full-bridge circuit and as a half-bridge circuit, an arrangement (A2) working as an up-converter coupled, at least via a capacitor, (C2) to the resonance converter (A3), and a transformer (T) in the resonance converter (A3) and realizing a point (7) at which the arrangement (A2) is capacitively (C2) coupled to the resonance converter (A3). The primary winding of the transformer (T) is divided and this dividing point is arranged as the point (7).
Claims18
An AC/DC converter comprising:
- an input for receiving a first AC voltage;
- a first rectifier arrangement for generating a rectified AC voltage from the first AC voltage;
- a first smoothing capacitor arrangement for smoothing the rectified AC voltage thereby forming a smoothed rectified AC voltage;
- a bridge circuit including a first, second, third and fourth switching element for converting the smoothed rectified AC voltage into a further AC voltage,
- a resonance converter comprising resonant circuit elements for converting the further AC voltage into a DC output voltage available on an output of the AC/DC converter;
- a control circuit for controlling the switching elements of the bridge circuit wherein, in a first mode, the bridge circuit is operated as a half-bridge circuit by said control circuit changing switching states of the first and second switching elements and not changing switching states of the third and fourth switching elements, and, in a second mode, the bridge circuit is operated as a full-bridge circuit by said control circuit changing the switching states of the first, second, third and fourth switching elements;
- and
- an arrangement working as an up-converter connected between the first rectifier arrangement and the first smoothing capacitor arrangement, said arrangement comprises at least one diode and a coupling capacitor, said coupling capacitor being coupled, on one side, to a junction point between the first rectifier arrangement and the at least one diode and, on the other end, to a junction point inside the resonance converter for capacitively coupling the arrangement working as an up-converter to the resonance converter, whereby, during the operation of the AC/DC converters, a potential modulated with the operating frequency of the resonance converter is fed back, characterized in that the AC/DC converter is capable of handling two different first AC voltages, wherein the control circuit provides an automatic change-over between the two modes of the bridge circuit in dependence on the value of first AC voltage applied, whereby with a low first AC voltage, the bridge circuit is operated as a full-bridge circuit, while with a high first AC voltage, the bridge circuit is operated as a half-bridge circuit.
5 more elements
An AC/DC converter comprising:
- an input for receiving a first AC voltage;
- a first rectifier arrangement for generating a rectified AC voltage from the first AC voltage;
- a first smoothing capacitor arrangement for smoothing the rectified AC voltage thereby forming a smoothed rectified AC voltage;
- a bridge circuit including a first, second, third and fourth switching element for converting the smoothed rectified AC voltage into a further AC voltage;
- a resonance converter comprising resonant circuit elements for converting the further AC voltage into a DC output voltage available on an output of the AC/DC converter;
- a control circuit for controlling the switching elements of the bridge circuit, wherein, in a first mode, the bridge circuit is operated as a half-bridge circuit by said control circuit changing switching states of the first and second switching elements and not changing switching states of the third and fourth switching elements, and, in a second mode, the bridge circuit is operated as a full-bridge circuit by said control circuit changing the switching states of the first, second, third and fourth switching elements;
- and
- an arrangement working as an up-converter connected between the first rectifier arrangement and the first smoothing capacitor arrangement, said arrangement comprises at least one diode and a coupling capacitor, said coupling capacitor being coupled, on one side, to a junction point between the first rectifier arrangement and the at least one diode, and, on the other end, to a function point inside the resonance converter for capacitively coupling the arrangement working as an up-converter to the resonance converter, whereby, during the operation of the AC/DC converter, a potential modulated with the operating frequency of the resonance converter is fed back, characterized in that
- the resonance converter comprises at least two inductances connected in series, and
- the junction point at which the arrangement operating as an up-converter forms a capacitive coupling with the resonance converter is located in the series connection between the two inductances.
7 more elements
Dependencies are inferred from the claim text.