WOLFRAM SYSTEM MODELER

DCVH43OpenCenter

Hydraulically actuated proportional control valve with four ports and three states

Diagram

Wolfram Language

In[1]:=
SystemModel["Hydraulic.Valves.DirectionalControl.HydraulicActuation.DCVH43OpenCenter"]
Out[1]:=

Information

This is a model of a control valve with six ports and three states. The valve has a tank port t, a pressure port p, two load ports a and b, and two pilot ports p1 and p2. The insignal, u, to the spool is the pressure difference between ports p1 and p2. The valve is controlled by a hydraulic spool with first-order dynamics; see SpoolH.

This valve is similar to DCVH43ClosedCenter; the only difference is the middle state. In this model, all ports are connected in the middle state. In the figure below, u is the pressure difference between ports p1 and p2.


Control valve with four ports and three states

Implementation

This valve basically consists of orifices controlled by a spool.

Parameters (9)

medium

Value: Oil()

Type: Medium

Description: Medium in the component

V

Value: 0.0001

Type: Volume (m³)

Description: Volume of control valve

Gleak

Value: 1e-020

Type: PressureDependentLeakage (m³/(s⋅Pa))

Description: Leakage between orifices

overlap

Value: 0

Type: Length (m)

Description: Spool overlap, a number between -1 and 1; 0 if no overlap

AMax

Value: 0.001

Type: Area (m²)

Description: Maximum opening area

Cd

Value: 0.62

Type: Real

Description: Coefficient of discharge for the opening

pMin

Value: 10000.0

Type: Pressure (Pa)

Description: Pressure difference when the valve starts to move

pMax

Value: 500000.0

Type: Pressure (Pa)

Description: Pressure difference when the valve has reached its maximum position

t1

Value: 0.01

Type: Time (s)

Description: Time constant for first-order system

Connectors (6)

port_p

Type: Port_a

Description: Port for hydraulic fluid (filled icon)

port_t

Type: Port_a

Description: Port for hydraulic fluid (filled icon)

port_b

Type: Port_b

Description: Port for hydraulic fluid (unfilled icon)

port_a

Type: Port_b

Description: Port for hydraulic fluid (unfilled icon)

port_p1

Type: Port_a

Description: Port for hydraulic fluid (filled icon)

port_p2

Type: Port_b

Description: Port for hydraulic fluid (unfilled icon)

Components (12)

medium

Type: Medium

Description: Medium in the component

volume_a

Type: Volume

Description: Fixed volume with fluid storage

volume_b

Type: Volume

Description: Fixed volume with fluid storage

volume_t

Type: Volume

Description: Fixed volume with fluid storage

volume_p

Type: Volume

Description: Fixed volume with fluid storage

rightState

Type: CrossOver4Port

Description: Basic building block for directional control valves

leftState

Type: Straight4Port

Description: Basic building block for directional control valves

middleState

Type: Open4Port

Description: Basic building block for directional control valves

abs1

Type: Abs

Description: Output the absolute value of the input

add1

Type: Add

Description: Output the sum of the two inputs

const

Type: Constant

Description: Generate constant signal of type Real

spoolH1

Type: SpoolH

Description: Model of a hydraulic spool