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
	port_b	Type: Port_b
	port_a	Type: Port_a
	port_pilot	Type: Port_a

Components (12)

	const	Type: Constant
	limiter2	Type: Limiter
	firstOrder	Type: FirstOrder
	limiter1	Type: Limiter
	division	Type: Division
	pressure_b	Type: PressureSensor
	pressure_a	Type: PressureSensor
	deadZone	Type: DeadZone
	gain1	Type: Gain
	gain2	Type: Gain
	add31	Type: Add3
	pressure_pilot	Type: PressureSensor