Rompower Technology Holdings, LLC

Det International Holding Limited

Ascom Energy Systems Ag

Other

Delta Energy Systems (switzerland) Ag

Rompower Inc.

Itt Corporation

Delta Electronics (thailand) Public Company Limited

Delta Electronics (thailand) Pcl.

Rompower Energy Systems, Inc.

Ionel Jitaru

Marco Antonio Davila

Andrei Stefan Savu

Mihai Bogdan Jitariu

Andrei Ion Radulescu

Iulian Busu

Bogdan Tudor Bucheru

Lucian Hriscu

George Casaru

Beldianu Vasile

Marco A Davila, Jr

Cosmin Andrei Tamas

Lucian Budica

Bogdan T Bucheru

Marco Davila

A switching power conversion apparatus includes an input voltage source, an output load, a first switch connected to a switching node, and a second switch connected to the switching node. An inductive element has a magnetizing current connected to the switching node. The inductive element delivers energy via the first and second switches from the voltage source to the load during power conversion cycles. A capacitance connected to the switching node can resonate with the inductive element during a portion of the power conversion cycles to cause a parasitic oscillation. A first clamp subcircuit is across the inductive element and contains a unidirectional auxiliary switch to trap energy from the inductive element and store it into the storage capacitor and prevent parasitic oscillation. The auxiliary switch is complementary to the first switch. A current source discharges the storage capacitor and uses the energy in the switching power conversion apparatus.

Energy extraction and utilization from the parasitic elements in power converters

A power converter formed by a multitude of power cells, wherein each of the power cells is implemented on a four-legged magnetic core placed on a multilayer PCB. Each cell contains rectifier means and resonant capacitors. The cells can be interleaved with the proper delay for reduction of a ripple current through output capacitors. The power cells can be interleaved for the purpose of splitting a high input voltage bus to reduce the voltage stress on the switching elements of the cells.

Magnetic structures for low leakage inductance and very high efficiency

A magnetic assembly formed by a custom magnetic core and its bobbin with interconnection pins is presented. This magnetic assembly leads to a higher power density of magnetic assembly and a better utilization of the volume inside a power converter, allowing a higher power density of the power converter and a higher efficiency through the minimization of the parasitic inductances.

High density magnetic structure

A magnetic and electrical circuit element including magnetic-flux-conducting posts, and a multi-layer structure formed with an electrically-conductive material. The multi-layer structure includes multiple layers forming a stack of layers along a length of the posts, said multi-layer structure configured as primary and secondary windings of a transformer. The primary winding is embedded in the multi-layer structure and wound around the magnetic-flux-conducting posts in such a way that a magnetic field induced in each of the magnetic-flux-conducting posts has a magnetic field polarity opposite to a polarity of the respective magnetic field of the magnetic-flux-conducting post adjacent the respective magnetic-flux-conducting post. Around each of the magnetic-flux-conducting posts, there is a respective one of the secondary windings connected to a semiconductor device. The magnetic-flux-conducting posts are connected magnetically by continuous magnetic-flux-conducting plates, each of which is shaped to ensure a continuous flow of the magnetic field successively through adjacent magnetic-flux-conducting posts.

A planar multilayer transformer in a power converter wherein winding arrangements and placement of shields reduces common mode noise to a level wherein the common mode inductor in an input EMI filter can be reduced and even eliminated decreasing the power dissipation and increasing the power density. The methods presented herein can reduce the number of layers in the multilayer PCB by eliminating the layers used for the shields and still be in full compliance with EMI requirements.

Planar multilayer transformer with minimum noise injection in between primary and secondary winding

A system for reducing common-mode noise includes a switch mode power supply having primary and secondary sides, primary and secondary side grounds, an input voltage source, a primary switch, a transformer, a core, and a power output. The primary and secondary sides each have a quiet termination. The transformer includes a primary winding, a secondary winding, and an active shield winding between the primary and secondary windings. The active shield winding has two terminations, is wound in a same direction as the secondary winding, and occupies a same axial position on the core as the secondary winding. One of the terminations of the active shield winding is connected to the quiet termination of the primary side, so that the terminations of the secondary winding and the active shield winding that are adjacent each other carry alternating voltages of a same polarity and a same amplitude.

Power transformer for minimum noise injection in between primary and secondary winding 'rompower active shield'

A two-transistor forward switching cell includes two primary switching elements connected between an input voltage source and a primary winding of a transformer. The switching elements are connected to the primary winding at opposite ends of the winding. Reset diodes are connected between one of the opposite ends of the primary winding and one termination of the voltage source, and between another of the opposite ends of the primary winding and another termination of the voltage source. The transformer has at least a secondary winding connected to drains of synchronous rectifiers. One of the rectifiers is on during at least a portion of a time when the switching elements are on. The other of the rectifiers is a freewheeling rectifier, is connected to at least one controlled current source, and is off when the switching elements are on. Both rectifiers are on for a common predetermined time.

Very high efficiency soft switching converter AKA the adjud converter

A method of optimizing the efficiency of an AC-DC converter, wherein the energy extraction time from the AC line is increased and as result the size of the bulk capacitor can be decreased and in applications wherein the size of the bulk capacitor is maintained constant the ripple across the bulk capacitor is decreased. The methods presented also increase the power factor in AC-DC converters. Extending the energy extraction from the AC line also lowers the RMS current through the input bridge and the input bulk capacitor. The reduction of the ripple across the bulk capacitor also increases the efficiency of the DC-DC converter, increasing in this way the overall efficiency of the AC-DC converter.

High efficiency AC-DC converter

A switching power conversion apparatus for converting power from an input voltage source to a load includes first and second switches connected to a switching node. An inductive element has a magnetizing current connected to the node, and the inductive element is connected to deliver energy via the first and second switches from the input voltage to the load during a succession of power conversion cycles. A capacitance connected to the node resonates with the inductive element to cause parasitic oscillation. A clamp subcircuit across the inductive element contains an auxiliary switch to trap energy and prevent parasitic oscillation, wherein the auxiliary switch is complementary to the first switch. A controlled voltage source injects energy in the inductive element, when the auxiliary switch turns off to discharge the parasitic capacitance by using trapped energy in the inductive element in addition to injected energy from the controlled voltage source.

Energy extraction from the parasitic elements in power converters

A magnetic structure in a power converter includes at least two multilayer boards, such as a primary board containing the primary windings and some auxiliary windings, and a secondary board containing the secondary windings and some auxiliary windings. The primary and secondary boards are on top of each other. On the layer on the primary board adjacent to the secondary board, is a dual function shield to reduce the total common mode noise in the converter towards zero. The controlled dual function shield can be placed on the secondary board on the layer adjacent to the primary board, and in some embodiments can be placed on both primary and secondary board on the layers adjacent to the other board. The embodiments herein offer a very good solution for cost reduction of the planar transformers and offers an avenue for total elimination of the common mode noise in a power converter.

Low noise multilayer transformer

Power converter electronic circuitries configured to harvest and store energy from at least the parasitic oscillation occurring during the operation thereof. Methodologies of using such energy for the current injection, carried out by discharging the parasitic capacitance across the switching elements to achieve zero voltage switching condition for these switching elements. In a specific case, the methodology of current injection (with the use of so harvested and stored energy) is self-adjusting, causing the optimization of the energy required to discharge the parasitic capacitance.

Harvesting energy from parasitic elements of a power converter

New and Useful magnetic structures are provided. One feature of the magnetic structures is that they are configured to help minimize the air gap reluctance, improving the magnetic structure's coupling coefficient. Another feature is that reducing the windings AC impedance of a magnetic structure is produced by shielding the winding under ears formed of magnetic material. Still another feature is that leakage inductance of a magnetic structure is reduced, by making ears with cuts which converge toward the magnetic rods that are used in the formation of the structure.

Magnetic structures for large air gap

A half bridge switching cell includes two primary switching elements and a transformer with primary and secondary windings. Synchronized rectifiers correspond to the primary switching elements such that each of the synchronized rectifiers conducts when the corresponding primary switching element is not conducting. Each secondary winding is connected to one of the synchronous rectifiers and to a common connection and controlled current source. The primary switching elements conduct during offset times separated by a dead time. A magnetizing current flows through the secondary windings and synchronous rectifiers during the dead time. The magnetizing current flows into the primary winding when each of the synchronous rectifiers is turned off after the dead time, discharging a parasitic capacitance across the one of the primary switching elements when the corresponding synchronous rectifier is turned off, thereby creating a zero voltage switching condition at turn on for the primary switching elements.

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Tucson, AZ, United States of America

Ionel Jitaru