9
Operation
9.1
Position/force control PFC
The SvP system operates a PGH internal gear pump. The displaced flow rate
results directly from the motor speed.
The pumps used have been especially optimized for variable-speed opera‐
tion. The pumps achieve little leakage at a high overall efficiency and a low
noise level. Depending on the application, sensors capture the pressure, cyl‐
inder position and motor speed and transmit the captured values to the drive
controller.
The drive controller compares these values to the command values set by
the control unit and controls the motor speed according to the system re‐
quirements.
1
Control (command values: s
cmd
= position of the hydraulic cylin‐
der, F
cmd
= force)
2
Drive controller (Control Section, Power Section)
3
Motor
4
Pump
3 + 4
Motor-pump unit
5
Hydraulic system
6
Pressure transducer (p
A act
= actual pressure value chamber A,
p
B act
= actual pressure value chamber B)
7
Position measurement (s
act
= actual position value)
Fig. 9-1:
System overview
x/F control
"x/F control" means "position/force control" (x: position, F: force).
Sytronix SvP 7020 PFC 03 Variable-Speed Positioning of Hy‐
draulic Axes
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Operation
RE 62314-B_Edition 01 Bosch Rexroth AG
