Eaton 9000X, Руководство пользователя

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9000X AF Drives User Manual
6-2
For more information visit: www.eaton.com MN04001004E
June 2009
Overview
The SVX9000/SPX9000 Control can be used to operate induction motors using the
applications included in the system software delivered with the drive. Higher performance
permanent magnet (PM) synchronous motors and other functions of the frequency converter
(FC) are accomplished by loading special applications with the 9000XLoad software tool. The
following sections describe how to commission the drive for motor control in all applications.
See the All-in-One or special application manual for additional startup information or details
on the parameters. Parameters are available (visible) based on the application selected, the
type of control (SVX or SPX), the option boards installed in the control and the version of the
system software loaded in the control. In general, the SVX controls are limited to V/Hz and
open loop speed control of induction motors while the SPX control will work with any
application and option board. Before starting the commissioning process, select the type of
control, option boards, and size of the drive to meet the needs of the application and check
that the latest system software is loaded. Open loop or sensorless control means motor
control is accomplished by the standard drive unit without added speed/position feedback
devices and associated option cards. Vector control means the drive can differentiate
between torque producing and magnetizing current when reading motor phase currents. The
“rotor flux oriented, current vector control” allows the AC drive to control an induction motor
in the same manner as a separately excited DC motor.
Open Loop Vector Control Operations
The SVX9000/SPX9000 Control normally operates an induction motor in V/Hz or open loop
vector control (speed control) mode. By default, the ID run is designed to automatically
configure parameters for the programmable volts per Hertz (V/f) curve and make a stator
resistance measurement for a standard induction motor. If the ID run does not give the
proper performance, manual tuning of the control is described in later sections.
Frequency Controlled Application
For pumps and fans the application is usually frequency controlled and there is no need for
high torque on low speed. A straight V/f curve (“linear” V/Hz ratio type) is all that is required
for proper operation. Since pumps and fans are variable torque, selecting “Squared” for
V/Hz ratio type will give some energy savings. Compensation for measured stator resistance
voltage drop will improve performance and selecting “Auto Torque Boost” will help start the
motor if necessary. The SLX/SVX controls will operate a PM motor open loop but manual
tuning of the V/f curve is required.
Speed Controlled Application
When an application is speed controlled and high torque at low speed is needed, it is often
necessary to complete the ID run; select auto torque boost to help start the motor and set the
drive to speed control mode to compensate for the slip of the induction motor.