GE Brivo OEC 715, Service Manual

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Brivo OEC 715/785/865/865 Mobile C-Arm X-Ray Product Service Manual
2-50
kV control and IGBT assembly
KV Control Board
The kV control board is mounted inside the C-Arm Mainframe. It is one part of X-ray generator. The kV control
board will provide the following functional and performance.
- Send out 4 channel PWM(Pulse Width Modulation) signal for IGBT inverter board
-
Provide insulated driver signal for IGBT
-
KV feedback control circuit
-
KV feedback value output
- Exposure control
-
KV value set
-
Protect circuit and error signal output
KV control board mainly consists of 5 function blocks, refer to kV control board block diagram:
PWM GENERATOR
KV control board provides PWM signal output. SG3525A pulse width modulator control circuits offer.
Improved performance and lower external parts count when implemented for controlling all types of
switching power supplies.
- 8.0 V to 35 V Operation
-
5.1 V ± 1.0% Trimmed Reference
-
100 Hz to 400 kHz Oscillator Range
- Separate Oscillator Sync Pin
-
Adjustable Dead time Control
-
Input Under voltage Lockout
-
Latching PWM to Prevent Multiple Pulses
-
Pulse–by–Pulse Shutdown
40KHz
PWM generator
DC bus
4 Input AC 20V
KV set
IGBT driver
HCPL316
IGBT inverter
board
1. KV min <25kV
2. KV max >120kV
3. KV unbalance
4. Over current
5. Short circuit
KV feedback
Current
Feedback
LED
Outpu
t
PI adjustor
ERROR output