WOLFRAM SYSTEM MODELER
SpoolHDoublePilotOperatedModel of a hydraulic spool |
 |
Diagram
Wolfram Language
In[1]:=
SystemModel["Hydraulic.Utilities.SpoolHDoublePilotOperated"]
Out[1]:=
Information
This is a model of a hydraulic spool with two additional pilot ports. It has four 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 a | |
 | : | Pressure at pilot port b | |
 | : | Pilot ratio for pilot port a | |
 | : | Pilot ratio for pilot port b |
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 (7)
| 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 |
| kpa |
Value: 1 Type: Real Description: Pilot ratio for pilot port a; a positive value helps port_a |
| kpb |
Value: 1 Type: Real Description: Pilot ratio for pilot port b; a positive value helps port_b |
| yMax |
Value: 1 Type: Real Description: Upper limit for output value |
| yMin |
Value: -1 Type: Real Description: Lower limit for output value |
Connectors (5)
 |
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_a |
Type: Port_a Description: Port for hydraulic fluid (filled icon) |
|
port_pilot_b |
Type: Port_a Description: Port for hydraulic fluid (filled icon) |
Components (15)
 |
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 |
|
pressure_pilot_a |
Type: PressureSensor Description: Sensor measuring absolute pressure |
|
pressure_pilot_b |
Type: PressureSensor Description: Sensor measuring absolute pressure |
 |
add1 |
Type: Add Description: Output the sum of the two inputs |
|
add2 |
Type: Add Description: Output the sum of the two inputs |
|
add3 |
Type: Add Description: Output the sum of the two inputs |