POWER ARCHITECTURE FOR REVOLUTION CT
Publication Date: 2017-May-15
The IP.com Prior Art Database
A novel power architecture for revolution CT systems comprises a large generator/alternator on the rotating side, located proximal to the X-Ray tube, and configured to power the X-Ray tube directly, yielding efficiency gains and reducing EMC issues.
The present disclosure relates generally to computed tomography (CT), and more particularly to a novel power architecture for revolution CT systems.
Conventional CT systems include VCT-HD systems and REVO systems. In the VCT-HD systems, HVDC power from a stationary side is sent to a rotating side by means of brushes and slip rings, which generate noise (e.g. a white noise), and further reduces the lifetime of the brush.
In the REVO systems, HVDC power is sent to an X-Ray inverter on the stationary side, and thereafter, AC power with high frequency is passed to rotating side by a contactless slip ring (CLSR). The AC power is then transferred to a HV transformer and an X-Ray tube tank. In this case, while the noise and the brush lifetime issue is treated, however, a resonance issue exists between the X-ray inverter on the stationary side, and the HV transformer on the rotating side. Furthermore, both the VCT-HD and the REVO systems have low efficiency and EMC issues.
Therefore, there exists a need for a power architecture that relieves the abovementioned issues in revolution CT systems.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a schematic illustrating a high voltage X-Ray generator.
FIG. 2 is a schematic illustrating the power architecture of a high voltage generator.
FIG. 3 is a schematic illustrating a comparison between pre-REVO and REVO power architectures.
FIG. 4 is a schematic of the proposed power architecture.
The present disclosure provides large alternator or generator on a
gantry, which is the output terminal windings in the rotating side of a CT scan
machine, while a magnetic field is generated on the stationary side of the CT scan
machine. The large alternator is capable of generating electric power when the
gantry is spinning. The electric power is converted to DC power by a rectifier,
and delivered to an X-ray inverter. The manner of providing power is similar as
in the VCT-HD system, however, without using any slip ring. The voltage and
power of the large alternator can be controlled using an Excitation Field
Control board on the stationary side when the gantry has different speed or when
an X-Ray tube needs more power for an explosion.
When the gantry is completely stopped, the alternator cannot generate power, and at such instance, power from X-ray inverter on the stationary side can be transferred to the rotating side by contactless slip rings, in the same manner as in the revolution system, however, in this case, we need small X-Ray inverter and CLSR windings. Most electric power of X-Ray tube is received from the alternator located very close to...