What This Chapter Contains - ABB ACS355 series User Manual

Operation principle and
hardware description

What this chapter contains

The chapter briefly describes the operation principle, layout, type designation label
and type designation information. It also shows a general diagram of power
connections and control interfaces.
Operation principle
The ACS355 is a wall or cabinet mountable drive for controlling asynchronous AC
induction motors and permanent magnet synchronous motors.
The figure below shows the simplified main circuit diagram of the drive. The rectifier
converts three-phase AC voltage to DC voltage. The capacitor bank of the
intermediate circuit stabilizes the DC voltage. The inverter converts the DC voltage
back to AC voltage for the AC motor. The brake chopper connects the external brake
resistor to the intermediate DC circuit when the voltage in the circuit exceeds its
maximum limit.
U1
V1
AC supply
W1
Operation principle and hardware description 27
Rectifier Capacitor
bank
Brake chopper
BRK-
Inverter
BRK+ / Common DC terminals
3
U2
M
V2
AC motor
3~
W2