G01R33/3852

SWITCHING AMPLIFIER AND METHOD FOR ESTIMATING REMAINING LIFETIME OF A SWITCHING AMPLIFIER

A switching amplifier includes a power device and a processing device. The power device is configured for powering a load and is comprised of a plurality of switches. The processing device configured to calculate a switch junction temperature for a bonding wire in each switch based at least in part on a power loss of each switch; generate a first accumulated fatigue damage of the bonding wire in each switch based on the switch junction temperature; and generate an estimated remaining lifetime of the switching amplifier based on the first accumulated fatigue damages of the bonding wires in each switch.

SWITCHING AMPLIFIRER AND METHOD FOR OPERATING SAME
20170322269 · 2017-11-09 ·

A method is used for operating a switching amplifier, the switching amplifier includes a plurality of cascade elements. The method includes: coupling the cascade elements in series between two terminals of a load; providing two leg circuits each comprised of switches in each of the cascade elements; and controlling all of the switches comprised in the switching amplifier using space vector modulation (SVM), such that a change of a common mode (CM) voltage generated by the switching amplifier is in a predetermined range.

Determination of a type of processing of signals transmitted by local coil

A method and an apparatus for a magnetic resonance imaging system are provided. A type of further processing of signals transmitted by a local coil to a magnetic resonance imaging (MRI) system is determined in dependence on information received in or from the local coil about a local-coil type of the local coil.

SWITCHING AMPLIFIER WITH ZERO VOLTAGE SWITCHING AND BALANCED THERMAL CONTROL ALGORITHM

A switching amplifier includes a plurality of cascade elements, each bridge circuit includes an inductive load coupled between a first leg terminal of one of the at least two leg circuits and a second leg terminal of another one of the at least two leg circuits. A first leg voltage of the first leg terminal have a phase shift relative to a second leg voltage of the second leg terminal, the phase shift is used for causing the inductive load to store electric energy and generating a minimum circulating current—I min or I min sufficient to effect conducting of a corresponding diode; each of the switches is configured to be turned on if the corresponding diode conducts current to effect zero voltage switching of the corresponding switch. The minimum circulating current—I min or I min is equal to a constant value.

LOW FIELD MAGNETIC RESONANCE IMAGING METHODS AND APPARATUS

According to some aspects, a laminate panel is provided. The laminate panel comprises at least one laminate layer including at least one non-conductive layer and at least one conductive layer patterned to form at least a portion of a B.sub.0 coil configured to contribute to a B.sub.0 field suitable for use in low-field magnetic resonance imaging (MRI).

Magnetic resonance imaging device

A magnetic resonance imaging device according to an embodiment includes a gradient amplifier, a battery, a detector, and a battery controller. The gradient amplifier supplies electric power to the gradient coil. The battery is charged with electric power that is supplied from the power supply. The detector detects a high power output request on the gradient amplifier. The battery controller controls to supply electric power charged in the battery in addition to electric power supplied from the power supply to the gradient amplifier when the high power output request is detected.

ENERGIZING AND DISCHARGING A SUPERCONDUCTING MAGNET OF AN MRI SYSTEM
20210405139 · 2021-12-30 ·

A magnetic resonance imaging (MRI) system includes a superconducting magnet assembly with a superconducting field coil for generating a stationary uniform main magnetic field. A gradient system includes a gradient coil for generating gradient magnetic fields and a gradient amplifier which is connectable to the gradient coil for driving the gradient coil. A switch assembly is adapted for galvanically coupling the superconducting field coil to the gradient amplifier. In this way, it is possible for energizing and discharging a superconducting magnet of an MRI system in an easy and cost-efficient way.

Method and system for compensating stray magnetic fields in a magnetic resonance imaging system
11209513 · 2021-12-28 · ·

In a method for compensating stray magnetic fields in a magnetic resonance imaging system with two or more examination areas: a value for a predefined first magnetic field to be applied in a first examination area, in addition to a basic magnetic field is provided; information defining a predefined sequence control pulse to be applied in a second examination area is provided; a stray magnetic field in the second examination area resulting from application of the first magnetic field in the first examination area is determined; a compensated sequence control pulse for the second examination area is calculated from the predefined sequence control pulse and the determined stray magnetic field; and the compensated sequence control pulse is applied to the second examination area.

Magnetic resonance gradient accessory providing tailored gradients for diffusion encoding

A system includes a magnetic resonance gradient accessory within an MRI system. The MRI system includes a magnet housing, a superconducting magnet generating a magnet field B0 to which a patient is subjected, shim coils, RF coils, receiver coils, magnetic gradient coils, and a patient table. The magnetic resonance gradient accessory creates local magnetic gradient fields critical to image generation and provides for diffusion encoding of a specific body region.

Optimization of a chronological sequence in an mr control sequence

Method for optimizing a chronological sequence in an MR control sequence according to which a magnetic resonator having a gradient coil unit including first and second gradient coils and a cooling layer is controllable. The MR control sequence has a first and second sequence modules configured to control the first and second gradient coils, respectively. The method comprises detecting a property including a cooling power of the cooling layer for the first gradient coil or the second gradient coil, or a feature which is representative of a chronologically preceding use of the gradient coil unit; determining a first requirement of the first sequence module on the first gradient coil; determining a second requirement of the second sequence module on the second gradient coil; and optimizing the chronological sequence in the first and second sequence module by taking into account the property and the first and second requirements.