Moog MSD Servo Drive, Device Help

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Image 7.70: “Leakage compensation” screen
ID Index Name Unit Description
2849 HYD_Lfe Leakage flow estimate
2849 0 lfe_Qmin l/min Leakage flow estimate: minimum value
2849 1 lfe_Qmax l/min Leakage flow estimate: maximum value
2849 2 lfe_K 1/ms Leakage flow estimate: gain
2849 3 lfe_Tn ms Leakage flow estimate: integration time constant
2850 HYD_PressCon Hydraulic pressure control parameters
2850 0 Kp rpm/bar Gain
2850 1 KpScale Gain scaling
2850 2 Tn ms Integration time constant
2850 3 Tv ms Differential time constant
Table 7.82: “Hydraulic - Volumetric flow rate” parameters
MOOG
ID No.: CB40859-001 Date: 11/2020
MSD Servo Drive - Device Help
201
7 Control
ID Index Name Unit Description
2850 4 Tp ms Integral-action time
2850 5 pMin bar Minimum permissible pressure
2850 6 pMax bar
Maximum permissible pressure
2850 7 QMin l/min Minimum flow rate
2850 8 QMax l/min Maximum flow rate
2850 9 PressWindow bar Pressure control parameters
2850 10 decmpLvl bar Level for active decompression
2850 11 decmpRate bar/s Rate for active decompression
2850 12 pActScale Scaling for pAct
2850 13 pAct2Scale Scaling for pAct2
2850 14 pRange_k % Pressure range threshold
2850 15 pRange_midpoint bar Pressure range midpoint
Table 7.82: “Hydraulic - Volumetric flow rate” parameters (continue)
7.11.9 Speed control
The speed of a hydraulic cylinder can be influenced directly with the controlled
volumetric flow rate that is flowing in. The cylinder speed can be determined by
means of a linear position sensor which is coupled to the cylinder. The values from
the cylinder model and the cylinder speed allow the steady-state volumetric flow rate
to be set with precision. (P 2840.13 - AltSpdCon = 0)
If, in the case of double-acting cylinders, force is to be applied in both directions at
will, the simplest application will require at least one changeover valve. In this case,
the speed magnitude will continue to be defined via the volumetric flow rate, i.e. via
the pump speed. Meanwhile, the force direction will be based on the valve position.
Within this context, it is important to take into account that the sign will be reversed in
the relationship between the volumetric flow rate and the speed and that, due to the
different piston/annulus area, the relationship will change as well. The actuation of a
changeover valve, as well as its consideration for the cylinder positioning, are part of
the hydraulic package.