Electric power conversion systems – Current conversion – Including d.c.-a.c.-d.c. converter
Reexamination Certificate
1996-04-10
2001-03-27
Sterrett, Jeffrey (Department: 2838)
Electric power conversion systems
Current conversion
Including d.c.-a.c.-d.c. converter
C363S097000
Reexamination Certificate
active
06208531
ABSTRACT:
BACKGROUND OF THE INVENTION
This invention relates to power converter configuration, control, and construction.
Power converters generally include power transfer components (e.g., transformers and switches) and control circuitry which governs the operation of the power transfer components to achieve desired operating characteristics. For example, in some zero current switching (ZCS) converters of the kind sold by Vicor Corporation, Andover, Mass. (see also U.S. Pat. Nos. 4,415,959, 4,441,146, and 4,675,797, incorporated by reference), the power transfer components are discrete components mounted on a printed circuit board.
Referring to
FIG. 1
, in a simple version of a ZCS converter, a main power transformer
10
has primary and secondary windings
12
,
14
which define primary and secondary electrical sides
16
,
18
of the converter. Power conversion occurs by quantized transfer of energy from the primary side to the secondary side during a succession of energy transfer cycles. Each energy transfer cycle begins and ends with the closing and subsequent opening of a switch
20
at times when the current through the switch is essentially zero.
A control circuit
22
governs the opening and closing of switch
20
so that the energy transfer cycles occur with a frequency that is varied to cause the converter to supply the output power at a desired voltage. A voltage sensor
24
detects Vout and information about Vout (i.e. control information) is fed back to a portion of the control circuit which turns the primary side switch on and off.
It is often important (e.g., for safety reasons) that the primary and secondary sides of the converter be isolated from one another. As a result, the transfer of control information from the secondary to primary sides is usually done via an isolation device (e.g., a transformer in which two windings are coupled by a permeable core, an opto-coupler, or a discrete light emitting device located adjacent to a discrete light detecting device) which is included in the control circuitry.
During construction of the converter, the control circuitry typically is formed by mounting discrete electronic components on the same circuit board that bears the power conversion parts, or on separate daughter boards which form an assembly to be mounted on the main power conversion board (see U.S. patent application Ser. No. 07/947,937, Providing Electrical Components for Circuit Assembly, filed Sep. 21, 1992, incorporated by reference).
Powercube Corporation and General Electric Corporation have offered modular building blocks (e.g., AC rectifier blocks, PWM conversion blocks, control assembly blocks, output rectifier blocks) from which a complete switching power supply could be assembled, by connecting blocks together by means of wires, electrical connectors or traces on a circuit board.
SUMMARY OF THE INVENTION
In general, in one aspect, the invention features a power conversion apparatus. A transformer having galvanically isolated windings defines a primary side and a secondary side of the power conversion apparatus. A switch couples power from a source on the primary side via the transformer to a load on the secondary side. A first circuit assembly has primary-side circuitry galvanically coupled to a port for connection to an input power source. The primary-side circuitry includes a primary-side communicator for sending or receiving control information used in controlling operation of the power conversion apparatus. A second circuit assembly has secondary-side circuitry galvanically coupled to a port for connection to a load. The secondary-side circuitry includes a secondary-side communicator for sending or receiving the control information. The first and second circuit assemblies are mechanically separable as assemblies from one another, are galvanically isolated from one another, and are configured to be placed in positions relative to one another to enable the primary-side and secondary-side communicators to cooperate to pass the control information.
Embodiments of the invention include the following features. The communicators comprise windings and the control information is passed by electromagnetic coupling between them. There is circuitry for passing the information by modulating a carrier. The coupling may be achieved without a permeable core linking the windings, or there may be a permeable core linking the windings. The windings are formed on surfaces of separate circuit boards. The first and second circuit assemblies are enclosed respectively in mechanically separate protective housings formed, for example, of a dielectric encapsulant. The housings of the two assemblies meet at respective mating surfaces and coupling occurs across the mating surfaces. Power conversion components may be mounted on the same circuit board as the assemblies.
In general, in another aspect, the invention features a control circuit apparatus. First circuitry is encapsulated to form a first discrete physical unit and is connected to respond to control information received from second circuitry encapsulated in a second discrete physical unit. The two physical units respectively include subparts of a device for conveying the control information via a galvanically isolated path.
In general, in another aspect, the invention features a method of providing control circuitry for use in manufacturing individual power converters in a mode in which the individual power converters all conform to a single general design, and different ones of the power converters have different operating characteristics achieved by different components used within the single general design, Supplies of different versions of a first discrete control circuit are provided as are supplies of different versions of a second discrete control circuit. For each of the individual power converters being manufactured, different versions of the first and second control circuits are selected to achieve desired operating characteristics in the power converters. The selected different versions are incorporated into each converter in orientations to permit them to communicate control information between them to achieve the desired operating characteristics.
In general, in another aspect, the invention features a power converter. A primary circuit assembly includes a primary winding of a power conversion transformer. A switch influences the coupling of power from an input port of the primary assembly to the primary winding. Primary side control circuitry opens and closes the switch. A secondary circuit assembly includes a secondary winding of the power conversion transformer, and control circuitry for receiving control information useful in determining when to open and close the switch. The primary and secondary circuit assemblies are encapsulated as distinct components and held in proximity to one another to permit coupling between the primary and secondary windings of the power transformer via a permeable core, and to permit communication of the control information between the secondary circuit assembly and the primary circuit assembly.
In general, in another aspect, the invention features isolation apparatus for transferring control information between primary-side and secondary-side circuitry in a power converter. First communication circuitry electronically modulates a carrier signal with the control information. First and second galvanically isolated communicators send and receive the carrier signal between the primary-side and secondary-side circuitries. Second communication circuitry, in response to a signal delivered by the second communicator, generates an electrical signal corresponding to the control information.
Embodiments of the invention include the following features. The carrier signal comprises a high-frequency electrical oscillation. The first and second communicators comprise conductive windings. The electronic modulation comprises amplitude modulation.
In general, in another aspect, the invention features a method for transferring control information between electromechanically independent primary
Bufano Louis A.
Vinciarelli Patrizio
Fish & Richardson P.C.
Sterrett Jeffrey
VLT Corporation
LandOfFree
Power converter having magnetically coupled control does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Power converter having magnetically coupled control, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Power converter having magnetically coupled control will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2498327