By default, the start lock position control loop gain is disabled. Prior to setting up the start lock position gain, the speed and current control loop gains

should be optimized. During start and following brake release, if there is any roll back movement of the sheave, the start lock position control loop

gain can be enabled.

NOTE

By default start optimization is disabled. In most cases correct adjustment of the speed and current control loop gains will provide good performance.

The start optimization feature can be enabled should mechanical imperfections exist.

The drive must be optimized by a responsible person who is familiar with the systems operation and safety requirements to avoid a safety

hazard. Correct adjustment should be carried out as detailed in the Installation and Commissioning guide to avoid the risk of product

damage a safety hazard.

CAUTION

10.2

Control loop gain adjustment

10.2.1

Current control loop

Current control loop gains

P Gain parameters I03 (Start), I08 (Run), I13 (Stop)

I Gain parameters I04 (Start), I09 (Run), I14 (Stop)

Current control loop filter

Current loop filter, parameters I05 (Start), I10 (Run), I15 (Stop)

The current control loop gains proportional (P) and integral (I) control the response of the current loop to a change in current (torque) demand during

start stop (brake control) and operation. The default values give satisfactory operation with most motors, however for best performance an autotune

should be carried out to achieve optimum values, this being either a static or rotating autotune.

The proportional current control loop gain parameter I03 (Start), I08 (Run) are the most critical in controlling the performance.

Manual adjustment of the current control loop gains are not recommended from the autotune values;

•

During a static or rotating autotune the drive measures both the resistance and inductance of the motor and sets up Stator Resistance (B35) and

Transient Inductance (B34) from these values the current loop gains are calculated.

•

Once the autotune has been completed and the current loop gains set-up these can be manually adjusted if required where for example motor

acoustic noise may be an issue.

The current loop filter defines the time constant of a first order filter that can be applied to the final current reference. The filter is provided to reduce

acoustic noise and vibration produced as a result of position feedback quantisation. The filter introduces a lag in the speed control loop, and so the

speed controller gains may need to be reduced to maintain stability as the filter time constant is increased. The current control loop filter is not

available in Open loop mode.

474

Electrical

Getting

User Menu A Commissioning

installation

started

Advanced

Diagnostics

Optimization

Parameters