Other

US Government As Represented by the Secretary of the Army

Trw Limited

Triad Microsystems, Inc.

Donald L Cronin

Daniel S Goldin

John J Biess

Bertrand F Farber

Hartmut K Gehm

A power filter resonant frequency modulation network for coupling between a load and a variable voltage direct current power source which is subjected to superposition of alternating current thereon at various frequencies and at various voltage levels, the filter including first and second series inductor arrangements in the positive and negative buses between the power supply and the load, with capacitive elements in parallel between the two buses. Each series inductor arrangement includes a first inductor in series with a frequency and voltage responsive inductive load device, which is a second inductor having a tertiary winding loaded with a coil wound about the core of a saturable reactor. The firing angles of the reactors are directly proportional to voltage and inversely proportional to voltage to provide a phase staggered change of inductance in the network. At higher frequencies and lower voltages, the loading reactors are out of saturation and present a very high impedance to the circuit, the effect resulting in a broadening of the normal high Q peaking within a range of frequencies at resonance.

Power filter resonant frequency modulation network

An electronic ballast for energizing fluorescent lamps comprising a converter including a rectifier and a filter for converting an alternating source voltage into a direct current voltage, a network including first and second switching transistors, a tank circuit having a primary winding of a transformer, a secondary winding of the transformer for providing feedback of a portion of the voltage developed across the tank circuits and a bias circuit coupled between the opposite ends of the secondary winding and the emitters of the transistor for alternatively applying bias to the transistors, the network serving to convert a direct current voltage into an amplified sinusoidal voltage having a high frequency, and fluorescent lamps connected in a series configuration coupled across the primary winding.

Electronic ballast having emitter coupled transistors and bias circuit

An improved series inductor/parallel inverter power stage and power staging ethod for a transistor controlled DC-DC power converter in which the integrating capacitance is located in the output of the power stage transformer and the series inductor has a secondary winding connected across this capacitance for transferring stored energy from the inductor primary directly to the transformer output rather than through the transformer, and current flow through the transformer primary is controlled by two parallel, alternately conducting pulse-width-modulated transistors in a manner such that only a single transistor is located in the main current flow path at any given time. The improved power stage is characterized by reduced power dissipation and peak voltage stresses on the transistors, increased simplicity, and improved reliability. A DC-DC power converter having at least two improved power stages of the invention arranged in parallel and adjusted for conduction of preset fractions of the total power in phased relation.

Series induction/parallel inverter power stage and power staging method

Disclosed is a multiple output DC-to-DC converter. The DC input power is filtered and passed through a chopper preregulator. The chopper output is then passed through a current source inverter controlled by a squarewave generator. The resultant AC is passed through the primary winding of a transformer, with high voltages induced in a plurality of secondary windings. The high voltage secondary outputs are each solid-state rectified for passage to individual output loads. Multiple feedback loops control the operation of the chopper preregulator, one being responsive to the current through the primary winding and another responsive to the DC voltage level at a selected output.

Growing community of inventors

Anaheim, CA, United States of America

Donald L Cronin