WEG CFW700, Programming And Troubleshooting Manual

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8
Available Control Types
CFW700 | 8-1
8 AVAILABLE CONTROL TYPES
The inverter feeds the motor with variable voltage, current and frequency, by means of whose the control of the
motor speed is obtained. The values applied to the motor follow a control strategy, which depends on the selected
type of control and on the inverter parameter settings.
Choose the control type in function of the static and dynamic, torque and speed requirements of the driven load.
Control modes and their main characteristics:
„
V/f: scalar control; it is the simplest control mode, by imposed voltage/frequency; with an open loop speed
regulation or with slip compensation (programmable); it allows multimotor operation.
„
V VW: Voltage Vector WEG; it allows a static speed control more accurate than the V/f mode; it adjusts itself
automatically to the line variations, and also to the load variations, however it does not present fast dynamic
response.
„
Sensorless Vector: it is a field oriented control; without motor speed sensor; able to drive any standard motor;
speed control range of 1:100; speed control static precision of 0.5 % of the rated speed; high control dynamics.
„
Vector with Encoder: it is a field oriented control; it needs motor encoder; speed control down to 0 rpm;
speed control static precision of 0.01 % of the rated speed; high static and dynamic performance of the speed
and torque control.
All these control modes are described in details in the chapters 9 - Scalar Control (V/f) , 10 - VVW Control and
11 - Vector Control , the related parameters and orientations regarding the use of each of these modes.