Danfoss VLT AutomationDrive FC 360 Quick Manual page 6

Introduction
1 1
1.6.1 Block Diagram of the Frequency
Converter
Illustration 1.1 is a block diagram of the internal
components of the frequency converter.
1 2
1 2
Area Component
1 Mains input
2 Rectifier
3 DC bus
4 DC reactor
4
®
VLT AutomationDrive FC 360
J1–J5
3 9 6
4
5
8
J6–J7
3 6
4
5
4
8
Functions
•
AC mains supply to the
frequency converter.
•
The rectifier bridge converts
the AC input to DC current to
supply inverter power.
•
Intermediate DC-bus circuit
handles the DC current.
•
Filters the intermediate DC
circuit current.
•
Provides mains transient
protection.
•
Reduces the root mean square
(RMS) current.
•
Raises the power factor
reflected back to the line.
•
Reduces harmonics on the AC
input.
Danfoss A/S © 03/2017 All rights reserved.
Area Component
5 Capacitor bank
6 Inverter
7
7 Output to motor
M
8 Control circuitry
7
M
9 Brake chopper
Illustration 1.1 Example of Block Diagram for a Frequency
Converter
Functions
•
Stores the DC power.
•
Provides ride-through
protection for short power
losses.
•
Converts the DC into a
controlled PWM AC waveform
for a controlled variable
output to the motor.
•
Regulated 3-phase output
power to the motor.
•
Input power, internal
processing, output, and motor
current are monitored to
provide efficient operation
and control.
•
User interface and external
commands are monitored and
performed.
•
Status output and control can
be provided.
•
Brake chopper is used in the
DC intermediate circuit to
control DC voltage when the
load feeds energy back.
MG06A702