3–16

“A” Group: Standard Functions

The V/f free-setting endpoint f7/V7 parameters must stay within the more basic inverter limits in order for the specified free-setting characteristic curve to be achieved. For example, the inverter cannot output a higher voltage than the input voltage or the AVR setting voltage (Automatic Voltage Regulation), set by parameter A082. The graph to the right shows how the inverter input voltage would clip (limit) the characteristic curve if exceeded.

Output voltage

V7 Voltage to output or AVR voltage

V6

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Output

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

B101 to

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

frequency

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

B113

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0

 

 

 

 

 

 

 

 

 

 

f6

f7

Hz

(odd)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

(even)

 

 

 

 

 

 

 

 

 

 

 

 

B100 to B112

 

 

Configuring Drive

Parameters

 

 

Sensorless Vector Control and, Sensorless Vector Control, 0Hz Domain – These advanced torque control algorithms improve the torque performance at very low speeds:

•Sensorless Vector Control – improved torque control at output frequencies down to 0.5 Hz

•Sensorless Vector Control, 0Hz Domain – improved torque control at output frequencies from 0 to 2.5 Hz.

These low-speed torque control algorithms must be tuned to match the characteristics of the particular motor connected to your inverter. Simply using the default motor parameters in the inverter will not work satisfactorily for these control methods. Chapter 4 discusses motor/ inverter size selection and how to set the motor parameters either manually or by using the built-in auto-tuning. Before using the sensorless vector control methods, please refer to “Setting Motor Constants for Vector Control” on page 4–65.

NOTE: When the inverter is in SLV (sensorless vector) mode, use B083 to set the carrier frequency greater than 2.1 kHz for proper operation.

NOTE: You must disable sensorless vector operation when two or more motors are connected (parallel operation) to the inverter.

Vector Control with Encoder Feedback – This method of torque control uses an encoder as a motor shaft position sensor. Accurate position feedback allows the inverter to close the velocity loop and provide very accurate speed control, even with variations in motor loads. To use encoder feedback you will need to add an SJ–FB Encoder Feedback Card in the inverter’s expansion bay. Please refer to “Expansion Cards” on page 5–5 in this manual or the SJ–FB manual for details.

The following table shows the methods of torque control selection.

 

“A” Function

Run

 

Defaults

 

 

 

 

 

 

 

 

Mode

 

 

 

 

Units

SRW Display

 

 

 

 

 

 

 

 

Func.

 

 

 

Edit

–FE

–FU

 

–FR

Name

 

Description

 

 

 

 

Code

 

Lo Hi

(EU)

(US)

 

(JP)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

A041

Torque boost method

Two options:

✘ ✘

00

00

 

00

—

>A041 V-Boost

 

selection

00

Manual torque boost

 

 

 

 

 

 

Mode

MANUAL

 

 

 

 

 

 

 

 

 

 

 

01

Automatic torque boost

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

A241

Torque boost method

Two options (for 2nd

✘ ✘

00

00

 

00

—

>A241 2V-Boost

 

selection, 2nd motor

motor):

 

 

 

 

 

 

Mode

MANUAL

 

 

 

 

 

 

 

 

 

 

 

00

Manual torque boost

 

 

 

 

 

 

 

 

 

 

01

Automatic torque boost