ABB ACS 600 MultiDrive, Руководство пользователя

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ACA 635 IGBT Supply Sections 2-1
Chapter 2 – Operation Basics
Operation of ISU The ISU is a four-quadrant switching-mode converter. The a.c. current
of the ISU is nearly sinusoidal at a unity power factor. In addition, the
power flow through the converter is reversible. As a default, the ISU
controls the DC link voltage to the peak value of the line-to-line voltage.
The DC voltage reference can be set also higher by a parameter.
Main Circuit Diagram A diagram of the main circuit of the IGBT supply is shown below.
Control
The control and modulation is based on the Direct Torque Control
(DTC) method typically used in ACS 600 motor control.
Two line
currents and DC link voltage are measured and used for the control.
The control boards are similar to the boards of the inverter.
Voltage Waveform
The high frequency switching and high du/dt slightly distorts the
voltage waveform at the input of the converter. The depth of the
voltage notches depends on the ratio of network inductance to total line
inductance (n AC choke inductance).
Control and Gate Drivers
Common DC bus
AC choke
U
c
U
2
U
1
I
u
Supply network
Converter
U
0
I
dc