Chroma 61705 - Theory of Operation; Overall System Description; Power Transfer Unit

Theory of Operation
6-1
6. Theory of Operation
6.1 Description of Overall System
Figure 6-1 shows the overall system. Main power flows through 3 modules of power transfer
unit. The A board is identified as user interface controller. It scans the front panel keys
through K board, and sends the settings and measurement messages to LCD module. The
optional E board performs remote control via GPIB or RS-232C interface.
Figure 6-1 The Structure of 61700 Series AC Source
6.2 Description of Power Transfer Unit
Figure 6-2 shows the power transfer unit. The A/D power stage is designated as I board,
and generates DC voltage from the line input. The G board of D/D stage takes power from
the A/D output. It generates two isolated DC outputs for D/A power stage. The H board of
D/A inverter generates AC output. The D/A power stage is through G board relays in parallel
or series control to obtain more current and higher voltage. B board is identified as DSP
processor and D/A controller. The DSP processor is applied to control output frequency and
voltage as well as to measure voltage and current.
Φ1 POWER MODULE
( Master )
Φ2 POWER MODULE
( Slave 1 )
Φ3 POWER MODULE
( Slave 2 )
A
Board
K
Board
LCD Display
Key
E
Board
GPIB
RS-232
Input Power
Output Power
T