Overview; Afdk Information - Trane CH530 Installation, Operation And Maintenance Manual

Overview

AFDK Information

The AFDK Adaptive Frequency™ Drive is a pulse width
modulated (PWM) design incorporating both an IGBT
(Insulated Gate Bipolar Transistor) active rectifier and
inverter. The drive may be refrigerant-cooled when
ordered as a replacement for a AFDE Adaptive Frequency
Drive. Otherwise, it may be water-cooled by a water-to-
water or water-to-air heat exchanger. It is designed for
460/480-volt application. This drive converts ac power to
dc power and back to ac power. The incoming 460/480
volts are converted to a constant 700 volts dc by the active
rectifier, and a section of capacitors is used to store the dc
voltage. A variable output is accomplished by PWM
control within the inverter. The dc output feeds the
Inverter IGBTs that switch on and off in response to the
gate driver to change the dc input voltage to a symmetrical
ac output voltage of desired magnitude and frequency.
The output frequency range is 38 to 60 hertz.
A combination of two distinct operating modes make up
the AFDK control within the chiller's UC800 or DynaView™
control. The controls can control the inlet vanes, and they
can also modulate impeller speed from 38 to 60 hertz. The
IGBTs control the speed in response to the UC800 or
DynaView compressor control signal. Circuit breakers,
surge capacitors, and ground fault protection are standard
on all AFDK units.
Some of the basic features of the drive are:
• Less than or equal to 5 percent current harmonic
distortion (TDD).
• Minimum efficiency of 97 percent at rated load and
60 Hz.
• Unit displacement power factor of 0.99 or better.
• Low inrush current.
• The current never exceeds the full load amps.
• The AFDK varies the motor speed in response to the
speed command from the UC800 or DynaView control.
The CenTraVac™ chiller control panel has full control of
the unit operation, including the start/stop functions. If you
encounter a fault condition or an alarm on the drive, the
chiller display will indicate "alarm" and an "alarm
message."
This manual covers the features and specifications that are
unique to the Adaptive Frequency Drives being produced
for Trane. Only product information is covered here that
supplements that presented in the standard Liqui-Flo
instruction manuals that ship with the unit.
6 AFDK-SVU01C-EN