Chapter 2 Product Information
ACH200 Series High Voltage Variable Frequency Speed Control System Operating Manual
12
circuit consists of protection, rectification, filtering, AC drive and bypass (optional). The
schematic diagram is shown in Figure 2-3:
Bypass
AC output
Three-phase AC
input
Rectifier
bridge
IGBT
Inverter bridge
Figure.2-3
The input power supply terminal R/S/T is connected to the three-phase low-voltage output of
the transformer secondary coil, which is rectified by a three-phase full bridge to charge the DC bus
and then inverted into a single-phase AC output via the H-bridge. The single-phase output of the
power unit is: ACI/ACO.
The unit control circuit controls the work of the whole unit by receiving signals from the main
control system, while the power unit also transmits its own voltage, fault information and status
information back to the main control system via optical fibre to realise the monitoring of the power
unit.
The power unit has a unit bypass function, one for IGBT bypass and one for relay bypass
(optional). When a unit fails, the power unit can be bypassed automatically to ensure that the
frequency control system continues to work normally.
2.2.2 System Component
The components of the ACH200 series high voltage AC drive speed control system include
an integrated AC drive cabinet, and a bypass cabinet (optional), as shown in Figure 2-4.
