Regulating device for a resonant converter

• US 20030067791A1
• Filed: 09/04/2002
• Published: 04/10/2003
• Est. Priority Date: 09/04/2001
• Status: Active Grant

• Current Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Elferich, Reinhold, Duerbaum, Thomas, Raets, Hubert
• Granted Patent: US 6,829,151 B2
• Time in Patent Office: Days
• US Class Current: 363/16
• CPC Class Codes: H02M 3/33561 having more than one ouput with independent control
• CPC Class Codes: H02M 3/3376 with automatic control of output voltage or current
• 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

Abstract

A resonant converter, a regulation method for a resonant converter and a switched-mode power supply with a resonant converter are proposed. A converter comprises an inverter for generating an AC voltage which is fed to a resonant arrangement with a capacitor and a transformer. The circuit provides two types of secondary units, each comprising a secondary winding of the transformer and at least one rectifier element. Secondary units of the first and second type are then distinguished by opposite orientation, for example, opposite direction of winding or oppositely oriented wiring. At least two output voltages are delivered on the output, a first output voltage of which being supplied as a direct output of a first-type secondary unit and a second output voltage as a “stack output” of a first-type secondary unit and a second-type secondary unit, preferably as a series combination of these secondary units. The stack output is then arranged to deliver a large power and the direct output to deliver smaller powers. The two output voltages can be regulated separately with a regulating device, the regulating device predefining the driving of the inverter, preferably for the generation of a pulse width modulated voltage. For example by suitably choosing frequency and duty cycle of the pulse width modulated voltage, the voltages can be regulated to set values independently of each other.

Claims

1. A resonant converter comprising

an inverter (12) for generating an AC voltage,

and a resonant arrangement (14) fed with the AC voltage and comprising at least one capacitor (C_S) and at least one transformer (16),

at least two types of secondary units (20a, 20b) being provided, each formed by at least one secondary winding (18a, 18b) of the transformer (16) and at least one rectifier element (Da, Db), first-type secondary units (20b) and second-type secondary units (20a) being distinguished by opposite orientations,

and at least two output voltages being supplied of which a first output voltage (Vb) is supplied by a first-type secondary unit (20b) and

a second output voltage (Vab10 being supplied by a first-type secondary unit (20b) and a second-type secondary unit (20a).

2. A resonant converter as claimed in claim 1, in which

a regulating device (22) for regulating the two output voltages (Vb1, Vab1) to a respective set value (Vbref, Vabref) is provided,

the regulating device (22) being arranged so that it predefines the driving of the inverter (12).

3. A resonant converter as claimed in claim 2, in which

the regulating device (22) predefines a driving of the inverter (12) so that

a pulse width modulated voltage is produced for feeding the resonant arrangement (14).

4. A resonant converter as claimed in claim 3, in which

the regulating device (22) is arranged so that it predefines the switching frequency (f) and the duty cycle (δ

) of the pulse width modulated voltage.

5. A resonant converter as claimed in one of the claims 2 to 4 in which

the regulating device (22) is arranged so that it processes the measured values of the first and second output voltage (Vb1, Vab1).

6. A resonant converter as claimed in one of the claims 2 to 4, in which

the regulating device (22) is arranged so that it processes the measured values of a first output voltage (Vb1) produced by a first-type secondary unit (20b),

and measured values of an output voltage produced by a second-type secondary unit (20a).

7. A resonant converter as claimed in claim 5, in which

the regulating device (22) is arranged so that a respective regulating difference (Serr1, Serr2) is formed for the first and second output voltage (Vb1, Vab1),

the regulating difference (Serr1) of the first output voltage (Vb1) being used for calculating the predefined value for the duty cycle (δ

)

and the regulating difference (Serr2) of the second output voltage (Vab1) being used for calculating the predefined value for the switching frequency (f).

8. A resonant converter as claimed in one of the preceding claims, in which

the first output voltage (Vb1) is supplied by a first first-type secondary unit (20b) and

the second output voltage (Vab1) is supplied by the first secondary unit (20b) combined in series with at least one second-type secondary unit (20a).

9. A resonant converter as claimed in one of the claims 1 to 7, in which

the first output voltage (Vb1) is supplied by a first first-type secondary unit (20c)

and the second output voltage (Vab1) is supplied by a second first-type secondary unit (20b) combined in series with at least a third second-type secondary unit (20a).

11. A switched-mode power supply comprising

a power supply input circuit for connection to the electricity power grid and for producing an intermediate circuit DC voltage (Vdc),

and a resonant converter (10, 30) as claimed in one of the claims 1-9 which is fed with the intermediate circuit DC voltage.

10. A regulation method for a resonant converter, in which

the converter (10, 30) comprises an inverter (12) for generating an AC voltage and a resonant arrangement (14) fed with the AC voltage and comprising at least one capacitor (C_S) and at least one transformer (16)

at least two types of secondary units (20a, 20b) being provided, each formed by at least one secondary winding (18a, 18b) of the transformer (16) and at least one rectifier element (Da, Db), first-type secondary units (20b) and second-type secondary units (20a) being distinguished by opposite orientations,

and at least two output voltages being supplied of which a first output voltage (Vb1) is supplied by a first-type secondary unit (20b) and

a second output voltage (Vab10 being supplied by a first-type secondary unit (20b) and a second-type secondary unit (20a),

in which the driving of the inverter (12) is predefined to regulate the first and second output voltage to a respective set value.