WOLFRAM SYSTEM MODELER
SpoolHPilotOperatedModel of a hydraulic spool |
 |
Diagram
Wolfram Language
In[1]:=
SystemModel["Hydraulic.Utilities.SpoolHPilotOperated"]
Out[1]:=
Information
This is a model of a hydraulic spool with an additional pilot port. It has three input pressure signals and y is the current spool opening.
Normalization of the characteristic curve
The opening of the valve depends on the pressure difference, dP, which depends on the pressures according to the equation below:
where
The parameter pOpen defines the pressure difference when the valve starts to open, and the parameter pSwitch defines the pressure at which the valve is fully open. The dynamics of the spool are a first-order system with the time constant t1.
Normalization of the characteristic curve
The opening of the valve depends on the pressure difference, dP, which depends on the pressures according to the equation below:
where
 | : | Pressure difference used for computing the spool position | |
 | : | Pressure at port a | |
 | : | Pressure at port b | |
 | : | Pressure at pilot port | |
 | : | Pilot ratio for pilot port |
The parameter pOpen defines the pressure difference when the valve starts to open, and the parameter pSwitch defines the pressure at which the valve is fully open. The dynamics of the spool are a first-order system with the time constant t1.
Parameters (6)
| pOpen |
Value: 10000.0 Type: Pressure (Pa) Description: Opening pressure |
|---|---|
| pSwitch |
Value: 500000.0 Type: Pressure (Pa) Description: Switching pressure |
| t1 |
Value: 0.1 Type: Time (s) Description: Time constant for first-order system |
| kp |
Value: 1 Type: Real Description: Pilot ratio; a positive value helps port_a |
| yMax |
Value: 1 Type: Real Description: Upper limit for output value |
| yMin |
Value: -1 Type: Real Description: Lower limit for output value |
Connectors (4)
 |
y |
Type: RealOutput Description: 'output Real' as connector |
|---|---|---|
 |
port_b |
Type: Port_b Description: Port for hydraulic fluid (unfilled icon) |
 |
port_a |
Type: Port_a Description: Port for hydraulic fluid (filled icon) |
|
port_pilot |
Type: Port_a Description: Port for hydraulic fluid (filled icon) |
Components (12)
 |
const |
Type: Constant Description: Generate constant signal of type Real |
|---|---|---|
 |
limiter2 |
Type: Limiter Description: Limit the range of a signal |
 |
firstOrder |
Type: FirstOrder Description: First order transfer function block (= 1 pole) |
|
limiter1 |
Type: Limiter Description: Limit the range of a signal |
 |
division |
Type: Division Description: Output first input divided by second input |
 |
pressure_b |
Type: PressureSensor Description: Sensor measuring absolute pressure |
|
pressure_a |
Type: PressureSensor Description: Sensor measuring absolute pressure |
 |
deadZone |
Type: DeadZone Description: Provide a region of zero output |
 |
gain1 |
Type: Gain Description: Output the product of a gain value with the input signal |
|
gain2 |
Type: Gain Description: Output the product of a gain value with the input signal |
 |
add31 |
Type: Add3 Description: Output the sum of the three inputs |
|
pressure_pilot |
Type: PressureSensor Description: Sensor measuring absolute pressure |
Used in Components (3)
 |
Hydraulic.Valves.DirectionalControl.Internal Static pilot-operated check valve |
 |
UnloadingReliefValveWithReversedPilot Hydraulic.Valves.FlowControl.Internal Static unloading relief valve with pilot ratio applied to port_a |
 |
Hydraulic.Valves.PressureControl.Internal Static unloading relief valve |