Medical imaging device

Patent metadata

Field	Value
Publication number	US-9788403-B2
Application number	US-201314383246-A
Country	US
Kind code	B2
Filing date	Mar 6, 2013
Priority date	Mar 26, 2012
Publication date	Oct 10, 2017
Grant date	Oct 10, 2017

Abstract

A medical imaging device includes an inverter with semiconductor switches for generating an AC voltage to be supplied to a load, a coil inductively coupled to a fastener that is electrically conducting, and a monitoring circuit for monitoring a current in the fastener based on a signal from the coil.

First claim

The invention claimed is:

1. A medical imaging device, comprising:
a semiconductor module including an inverter having semiconductor switches, the inverter being configured to generate an AC voltage;
a load configured to consume the AC voltage for generating an image for output by the medical imaging device;
a coil configured to provide a signal indicative of a current in a semiconductor switch of the semiconductor switches;
a mechanical fastener configured to fasten the semiconductor module to a supply line of the semiconductor module, the mechanical fastener being further configured to fasten the semiconductor module to the coil, wherein the mechanical fastener is electrically conducting; and
a monitoring circuit configured to monitor the current in the semiconductor switch based on the signal from the coil,
wherein the coil is inductively coupled to the mechanical fastener, wherein the coil is arranged between the semiconductor module and the supply line, and wherein the coil is arranged around the mechanical fastener for sensing a current through the mechanical fastener and providing the signal indicative of the current in the semiconductor switch.

2. The medical imaging device of claim 1 ,
wherein the coil is a toroidal coil surrounding the mechanical fastener.

3. The medical imaging device of claim 1 ,
wherein the semiconductor switches comprise an insulated-gate bipolar transistor (IGBT).

4. The medical imaging device of claim 1 ,
wherein the inverter comprises an inverter leg with at least two semiconductor switches, and
wherein the mechanical fastener is configured to fasten the supply line to an input of the inverter leg.

5. The medical imaging device of claim 1 ,
wherein the inverter comprises an inverter leg with at least two semiconductor switches, and
wherein the mechanical fastener is configured to fasten the supply line to an output of the inverter leg.

6. The medical imaging device of claim 1 , wherein:
the semiconductor module houses the monitoring circuit and the inverter including the semiconductor switches, and
the coil is inductively coupled to the mechanical fastener at an input of the semiconductor module.

7. The medical imaging device of claim 1 ,
wherein the coil is accommodated between the supply line and an input of the semiconductor module, and wherein the mechanical fastener fastens the coil to the input of the semiconductor module.

8. The medical imaging device of claim 1 ,
wherein the monitoring circuit comprises an integrator for integrating the signal from the coil
to produce an integrated signal.

9. The medical imaging device of claim 1 , further comprising:
a resonance circuit connected to an output of the inverter.

10. The medical imaging device of claim 1 , further comprising:
a transformer for transforming the AC voltage from the inverter into a first higher AC voltage higher than the AC voltage; and
a high voltage generator for generating a second higher voltage, higher than the first higher AC voltage, to be supplied to an X-ray tube for generating the image for output by the medical imaging device.

11. The medical imaging device of claim 1 , wherein the mechanical fastener is a screw.

12. A method for operating a medical imaging device, the method comprising acts of:
switching semiconductor switches of an inverter housed on a semiconductor module of the medical imaging device for generating an AC voltage;
supplying the AC voltage to a load for generating an image for output by the medical imaging device;
generating a signal in a coil indicative of a current in a semiconductor switch of the semiconductor switches;
fastening by a fastener the semiconductor module to the coil and to a supply line of the semiconductor module, wherein the fastener is electrically conducting;
inductively coupling the coil to the fastener, wherein the coil is arranged between the semiconductor module and the supply line, and wherein the coil is further arranged around the mechanical fastener for sensing a current through the mechanical fastener and providing the signal indicative of the current in the semiconductor switch; and
determining a current signal based on the signal of the coil, the current signal indicating the current in the semiconductor switch.

13. The method of claim 12 ,
wherein the switching act switches the semiconductor switches such that a frequency of the AC voltage is above 10 kHz.

14. The method of claim 12 , further comprising acts of:
determining the current signal by integrating the signal from the coil to produce an integrated signal; and
detecting an over-current by comparing the integrated signal with a reference signal.

15. The medical imaging device of claim 8 , wherein the monitoring circuit comprises a comparator for comparing the integrated signal with a reference signal.

16. The method of claim 12 , wherein the switching act switches the semiconductor switches such that the inverter is operated in a resonant mode.

Assignees

• Koninklijke Philips Nv

Inventors

• Mrusek Helmut

Classifications

• G01R15/181

  using coils without a magnetic core, e.g. Rogowski coils · CPC title

• H02M7/537

  using semiconductor devices only, e.g. single switched pulse inverters · CPC title

• H05G1/20 Primary

  with high-frequency AC; with pulse trains {(pulse generators in general H03K3/00, H03K4/00)} · CPC title

• H02M1/32

  Means for protecting converters other than automatic disconnection · CPC title

• H05G1/265

  Measurements of current, voltage or power · CPC title