Abstract:
A high frequency matrix transformer power converter module includes a dedicated, pre-wired secondary winding, inductor and filter capacitor wherein the electrical conductor forming the dedicated secondary winding is made from a flat ribbon material and passes through adjacent cores forming the interdependent magnetic elements of the matrix transformer such that helical portions of the conductor forming the winding are in complementary arrangement within the core structure and provide an opening through which a second electrical conductor forming a primary winding may be inserted after the module is constructed to obtain the desired transformation characteristics. A number of modules may be arranged side-by-side to provide a higher power output wherein the output voltage busses of the modules are connected together and wherein through holes of each module are in registry to permit wiring of an undedicated primary winding to obtain the desired power output.
Abstract:
A flat matrix transformer or inductor is made of a plurality of interdependant magnetic circuits, arranged in a matrix, between and among which electrical conductors are interwired, the whole cooperating to behave as a transformer or inductor. The flat matrix transformer or inductor has several advantageous features, among them compact size, good heat dissipation and high current capability. A flat matrix transformer or inductor can be very flat indeed, nearly planar, and can be built using printed circuit board techniques. A flat matrix transformer can insure current sharing between parallel power sources, and/or between parallel loads. The flat matrix transformer can be configured to have a variable equivalent turns ratio.
Abstract:
A tracking lens system for solar collectors or skylights comprises a first array of condensing lenses, a movable array of diverging lenses, and a second array of condensing lenses. By moving the array of diverging lenses, sunlight incident from any small angle can be tracked. The light leaving the tracking lens system can be parallel rays coaxial with the lens system, or can be focused upon a collecting means.
Abstract:
A minimalized power converter has a square-wave voltage source operating at 100 percent duty-ratio, a series inductance and a rectifier. A high frequency square-wave power distribution system comprises a plurality of minimalized power converters connected by a common ac power distribution link. Because the ac power distribution link carries current at a high frequency, the square-wave may be degraded by the stray inductance with distance. Re-squaring circuits along the length of the ac power distribution link operating synchronously restore and preserve the integrity of the square-wave. The minimalized power converter is very flexible and has very fast dynamic response, being able to make very fast controlled current transitions from any current to any other current, including zero or current reversal (same voltage, opposite current flow).
Abstract:
The interleaved common mode transformer is a transformer particularly well suited for providing low voltage, high current dc outputs. Improving the efficiency of low voltage, high current transformer circuits requires a multi-faceted approach. Ac terminations and ac currents in connecting circuitry are particularly troublesome, so the input and output terminations of the transformer are dc. To utilize the winding fully, a common-mode push-pull configuration with common mode capacitors is used. Stray capacitance is less of a concern than leakage inductance at low voltages, so the windings are highly interleaved. Separate parallel secondary windings are used, an ac winding primarily for the ac currents, and a dc winding primarily for dc currents and heat sinking. The ac windings are thin; approximately two times the penetration depth. The dc windings are substantial, for low voltage drop and good heat sinking. For economical construction with minimum height, plated circuit board fabrication methods and materials are used for the windings. 100 percent duty-ratio switching is preferred to minimize core losses and reduce filtering requirements, as the filters are lossy.
Abstract:
The output voltage of a dc—dc transformer having a ratio of approximately m/n, and which is powered from a main power supply having a remote sense input, can be stabilized by feeding the output of the dc—dc transformer to the remote sense input of the main power supply through an amplifier having a voltage gain of m/n.
Abstract:
In a low voltage, high current power supply having very fast transitions of the load current, as in certain power supplies for microprocessors, the circuit impedances, particularly the stray inductance of the connector, are a major problem. If the voltage regulator circuits are separated from the output capacitor and brought to separate contacts in the connector, only connecting together on the load side, the voltage regulator will be much better able to overcome the connector impedance. The connector may be a printed connector, in which the metal surfaces of the internal layers of a multilayer printed circuit card are extended successively and mate with a similar complementary printed connector. To overcome high frequency effects, the power bus is a multilayer interleaved bus. Vias conduct the high frequency component of the current much more effectively at the edge of a stack of foil layers, so the power bus is strongly digitated to increase the periphery.
Abstract:
In a multiphase buck converter running at precise duty cycles which have an inverse integer relationship with the number of phases and a precise synchronized phase relationship, it is possible to have zero output ripple. If the output inductors are replaced with coupled inductors having nominally the same inductance, and the second windings of the inductors are wired in a loop with correct phasing, under steady state conditions the voltage drop around the loop will be zero. A small voltage injected into the loop can cause very fast transitions in current in the loop, and those currents will be reflected to the first windings of the inductors as a very rapid transition in the output current. This converter has no dc voltage control capability, so it is preferably used with a pre-regulation stage as the control of the dc output voltage. Dynamic voltage control is very fast, as the current into the output capacitor can change very rapidly.
Abstract:
This invention teaches that the heat sink and/or the object from which heat is to be removed may have significant flexibility. Indeed, it may be advantageous for one or both to have significant flexibility in that it allows good conformity for good thermal contact even if one or the other is uneven. The heat sink is attached to the object from which heat is to be removed with a good adhesive or solder under vacuum or with external pressure. The flexible heat sink may be much smaller and lighter in weight than a conventional heat sink. It may use less material and have less stringent machining requirements, so it may be much more economical to fabricate and use. Because a vacuum is used to pull the interface together at all points, there are fewer gaps or voids and the adhesive layer may be much thinner, for improved heat conduction.
Abstract:
A fan with heat sink comprises a plurality of closely spaced sheet metal fins closely proximate to the blade tips of an axial flow fan. The high velocity air and blade tip vortices cooperate to provide exceptional heat transfer. The metal fins are retained in a fan duct comprising a metal cylinder under high force for good heat transfer. In one embodiment of the invention, the fins are formed with a conical displacement, lessening their diameter, and are flattened and spread in the fan duct, to have high contact pressure for good heat flow. In another embodiment of the invention, the heat sink fins are formed from strip, for very low scrap, and are wrapped around reinforcing rings so that they may be installed in the fan duct with high force for good thermal contact. In another embodiment of the invention, the fan duct comprises a plurality of posts rising from a cold plate, and the heat sink fins are pressed thereon with high force.