Lucent Technologies Inc.

Tyco Electronics Power Systems, Inc.

Joao Luiz Andres

Minghua Fu

Michael Ray Bell

Loveday Haachitaba Mweene

Jacob Scaria

Alessandro A Cervone

Juan Niglio

The present invention provides a phase voltage circuit. In one embodiment, the phase voltage circuit includes a line voltage stage coupled to at least three input voltage lines and configured to provide at least two corresponding line voltages. Additionally, the phase voltage circuit also includes a difference voltage stage coupled to the line voltage stage and configured to provide at least one phase voltage from the at least two corresponding line voltages.

Circuit, method and system for providing one or more phase voltages from input voltages

The present invention provides a neutral point controller for use with a three level rectifier. In one embodiment, the neutral point controller includes a primary drive circuit configured to provide primary drive signals for the three level rectifier thereby establishing output voltages having a common neutral point. Additionally, the neutral point controller also includes a current balancing compensator coupled to the primary drive circuit and configured to maintain the common neutral point within a predefined voltage by adjusting the primary drive signals based on a current balancing feedback signal. In an alternative embodiment, the neutral point controller further includes a duty cycle compensator coupled to the current balancing compensator and configured to maintain the common neutral point within the predefined voltage by adjusting the primary drive signals based on a direct balancing pulse width modulation signal.

Neutral point controller, method of controlling and rectifier system employing the controller and the method

The present invention provides magnetic structure, particularly an isolation transformer, which includes a shield to prevent radiation of electromagnetic interference ('EMI'). The magnetic structure includes a support structure, or bobbin, on which are mounted windings formed from electrical conductors. The windings are electrically connected to termination points, which provide the electrical interconnections for the magnetic structure. A magnetic core can be included in the support structure to provide optimal magnetic properties to the device. An EMI shield formed from a metallic foil such as copper is wrapped around the winding to prevent the radiation of EMI. The EMI shield is connected to a shield pin in the support structure by a conductive strap such that the shield pin is electrically connectable to a fixed potential through a safety rated capacitor to provide a low impedance path for currents induced in the EMI shield. The magnetic structure is particularly useful as an isolation transformer in an isolated power supply.

Electromagnetic interference shielding for small magnetic devices

In a switching power supply generating at least a first output voltage and a second output voltage, the second output voltage, being of lower potential is applied to a linear regulator, the power supply further including a storage capacitor on the first output, a holdover circuit includes a comparator circuit for monitoring the first output voltage and for generating an output signal when the first output voltage decreases below predetermined value. A switch is connected to the storage capacitor, the comparator circuit, and the linear regulator. The switch is activated by the comparator output signal and applies the voltage stored in the storage capacitor to the linear regulator. A clamp circuit is connected to the switch for limiting the magnitude of the voltage from the storage capacitor to the linear regulator when the switch is activated.

Growing community of inventors

Mesquite, TX, United States of America

Joao Luiz Andres