WOLFRAM SYSTEM MODELER

SpoolHPilotOperated

Model 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
: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)

PilotOperatedCheckValve

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

UnloadingReliefValve

Hydraulic.Valves.PressureControl.Internal

Static unloading relief valve