Function extension:
In the i700 servo inverter, square interpolation can now be selected as an additional option for the interpolation of set and actual positions.
The control loops are more frequently processed in the i700 (cycle time T = 0.250 ms) than the position values are transferred via the EtherCAT bus (typical cycle time: T = 1.000...8.000 ms).
The interpolation function is used to generate intermediate values in order to smooth the 'bigger' steps between the transferred setpoints. In this way, acceleration/deceleration processes are better displayed.
Parameter 0x60C0 "Interpolation algorithm":
Linear interpolation:
The position difference between two transferred position values is (linearly) in equal steps distributed to the number of internal control cycles. The resulting characteristic between two transferred positions is a straight line. Constant speed during the interpolation cycle is assumed.
Square interpolation:
Approximated distribution of the position difference between two transferred position values under consideration of speed and acceleration, if any.
During an acceleration or deceleration phase, the fine steps of the position characteristic are not equally big, corresponding to the parabolic position characteristic during an acceleration or deceleration phase. To generate the square characteristic (parabola), the i700 evaluates the last three position values - a parabola is unambiguously defined by three points.
Contained in which products?
- i700 servo inverter from V01.03.08.9047
Application:
In most applications, the newly implemented square position interpolation leads to an improved drive performance.
We therefore recommend to use the square interpolation (0x60C0 = [-1]).
