High Voltage Generator Flashcards
Allows generator to be disconnected from power line
Circuit breaker
Limits current from power line to generator
Circuit breaker
Used to change incoming power to levels needed to produce xrays
High voltage generator
Reponsible for increasing the output voltage from the auto transformer to kVp
High voltage section
Purpose of oil in high voltage section?
electrical insulation
The second voltage is higher than the primary voltage
Step up transformer
High voltage only operates on
Alternating current
Voltage wave form is
Sinusoidal
Difference bet primary and secondary waveform
Amplitude
Derived from a cell and uni-directional
Positive and negative terminals are FIXED
Direct current
Current changes its direction after equal intervals of time
It has no fixed terminals
Alternating current
Produced by acceleration of electrons from cathode to anode
Xrays
Process whereby alternating current is converted to direct current
Rectification
Electronic device that allows current flow in one direction
Rectifier
A device which performs the opposite function ( DC to AC)
Inverter
Electronic device that contains two electrodes
Diode
Conductor through which electric current is passed
Electrode
Solid state rectifiers are made of ___
Silicon
The ability to conduct electricity
Semiconductors
2 types of semi conductors
N-type
P-type
Have loosey bound electrons
N-type
Have spaces (holes) there are no electrons
P type
Flow of electrons
Electric current
The current that passes through the xray tube exists inly during positive half of the cycle
Unrectified voltage
Types of rectification
Half wave rectification
Full wave rectification
Simpliest type of rectifier since it only uses one diode
Half wave rectification
Consists of at least four diodes in high voltage circuit
Full wave rectification
Four rectifiers arranged this way are called
Bridge rectifier
Characterized the voltage waveform
Voltage ripple
Characteristics of waveforms
Period
Frequency
Amplitude
Length of time
Period
Time for sine waves
Periodic time
Time of square waves
Pulse width
Number of waveform
Frequency
Intensity of the signal
Amplitude
Voltage waveforms are produced by
Single phase power
It exist when the xrays are produce near the peak voltage
Pulsating xray beam
Caused by the alternate in swing in voltage from 0 to maximum potential
Pulsating xray beam
Xray produced with SPP has a value of near zero ate of little value because of lower energy
Pulsed Radiation
Multiple voltage waveform are superimposed on one another resulting a nearly constant high voltage
Three-phase power
It uses inverter circuits
High frequency voltage generator
Converts DC into a series of square pulses
Inverter circuits
Near constant potential voltage waveform improving image quality at lower patient radiation dose
High frequency generator
Guidelines set by the manufacturer
Power rating
