Resonant commutation and quasi-trapezoidal current control in electronic transformers
View Patent ↗Power converters including electronic-embedded transformers for current sharing and load-independent voltage gain are described. An example power converter system includes an input, an output, a power converter between the input and output, and a controller. The converter includes a first bridge, a second bridge, and an electronic-embedded transformer between the first and second bridge. The electronic-embedded transformer includes a bidirectional coupling switch bridge. The controller generates drive control signals for quasi-trapezoidal current modulation control of the bidirectional coupling switch bridge. The controller is configured to generate the drive control signals based on a commutation coefficient k and a switching frequency for the power converter. The commutation coefficient k can be set based on an inductance in the electronic-embedded transformer, a capacitance in the bidirectional coupling switch bridge, and a margin for resonant current commutation.
1 . A power converter system, comprising:
an input and an output;
a power converter between the input and the output, the power converter comprising:
a first bridge of switching devices;
a second bridge of switching devices; and
an electronic-embedded transformer between the first bridge and the second bridge, the electronic-embedded transformer comprising a bidirectional coupling switch bridge; and
a controller configured to generate drive control signals for quasi-trapezoidal current modulation control of the bidirectional coupling switch bridge, wherein:
the bidirectional coupling switch bridge of the electronic-embedded transformer comprises bidirectional switching devices Q 1 and Q 2 and capacitors C o1 and C o2 ;
the drive control signals control switching operations of the bidirectional switching devices Q 1 and Q 2 ;
the controller is further configured to generate the drive control signals based on a commutation coefficient k and a switching frequency for the power converter; and
the commutation coefficient k is calculated based on an inductance L k in the electronic-embedded transformer and a capacitance of the capacitors C o1 and C o2 .
2 . The power converter system according to claim 1 , wherein the controller is further configured to generate the drive control signals for the bidirectional coupling switch bridge for transformer current commutation in the electronic-embedded transformer.
3 . The power converter system according to claim 1 , wherein the controller is further configured to:
generate switching control signals for the first bridge of switching devices and the second bridge of switching devices; and
generate the drive control signals for quasi-trapezoidal current modulation control of the bidirectional coupling switch bridge.
4 . The power converter system according to claim 1 , wherein the commutation coefficient k is calculated based on an inductance L k in the electronic-embedded transformer, a capacitance of the capacitors C o1 and C o2 , and a margin for resonant current commutation.
5 . The power converter system according to claim 1 , wherein the electronic-embedded transformer comprises a module in the power converter.
6 . The power converter system according to claim 1 , wherein the electronic-embedded transformer comprises a plurality of electronic-embedded transformers coupled in parallel between the first bridge and the second bridge.
7 . The power converter system according to claim 1 , wherein the electronic-embedded transformer comprises a plurality of electronic-embedded transformers coupled in series between the first bridge and the second bridge.
8 . An electronic-embedded transformer for a power converter, comprising:
a primary winding;
a secondary winding;
a resonant inductor for use in the power converter, the resonant inductor being embodied as leakage inductance among the primary winding and the secondary winding;
a bidirectional coupling switch bridge; and
a controller configured to generate drive control signals for quasi-trapezoidal current modulation control of the bidirectional coupling switch bridge, wherein:
the bidirectional coupling switch bridge comprises bidirectional switching devices Q 1 and Q 2 and capacitors C o1 and C o2 ;
the drive control signals control switching operations of the bidirectional switching devices Q 1 and Q 2 ;
the controller is further configured to generate the drive control signals based on a commutation coefficient k and a switching frequency for the power converter; and
the commutation coefficient k is calculated based on an inductance L k in the electronic-embedded transformer and a capacitance of the capacitors C o1 and C o2 .
9 . The electronic-embedded transformer according to claim 8 , wherein the commutation coefficient k is calculated based on an inductance L k in the electronic-embedded transformer, a capacitance of the capacitors C o1 and C o2 , and a margin for resonant current commutation.
10 . The electronic-embedded transformer according to claim 9 , wherein bidirectional coupling switch bridge comprises a monolithic bidirectional switch.
11 . The electronic-embedded transformer according to claim 8 , wherein the electronic-embedded transformer comprises a module in the power converter.
12 . A power converter system, comprising:
a power converter comprising:
a first bridge of switching devices;
a second bridge of switching devices; and
an electronic-embedded transformer between the first bridge and the second bridge, the electronic-embedded transformer comprising a bidirectional coupling switch bridge, the bidirectional coupling switch bridge comprising switching devices Q 1 and Q 2 and capacitors C o1 and C o2 ; and
a controller configured to:
generate switching control signals for the first bridge of switching devices and the second bridge of switching devices; and
generate drive control signals for the switching devices Q 1 and Q 2 , wherein:
the controller is further configured to generate the drive control signals based on a commutation coefficient k and a switching frequency for the power converter; and
the commutation coefficient k is calculated based on an inductance L k in the electronic-embedded transformer, a capacitance of the capacitors C o1 and C o2 , and a margin for resonant current commutation.
13 . The power converter system according to claim 12 , wherein the controller is further configured to generate the drive control signals for the switching devices Q 1 and Q 2 for transformer current commutation in the electronic-embedded transformer.
14 . The power converter system according to claim 12 , wherein the electronic-embedded transformer comprises a plurality of electronic-embedded transformers coupled in parallel between the first bridge and the second bridge.