V/f operation with current boost (Imin): discontinuity in the torque curve at the release point of the current boost (corrected from V01.06.04)

Corrected from:

Servo Inverter i950 FW: as of V01.06.04.2154

Response of the new version:

The described discontinuities in the torque curve in a certain speed range no longer occur.

What happens?

According to the specification, the current boost is only effective in the lower speed range, up to half the rated motor speed.

At speeds at the release point of the current boost, in the range of half the rated motor speed, a discontinuity in the torque curve occurs.

When does the behaviour occur?

Motor control mode V/f characteristic operation (VFC) and
Use of current boost (Imin controller).

Which products are affected?

Servo inverter i950 FW

Short-term measures / Evaluation / Recommendations:

The occurring discontinuity in the torque is rather low, so that the described behaviour will have rather little effect in practice. In most cases it is hardly noticeable.

If, contrary to expectations, the effect on the machine behaviour should be significant, it is possible to use the voltage boost (0x2B06) instead of the current boost.

Note: Always activate only one of the two boost functions.

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