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Proportional Valve Actuator

Models a power-controlled valve actuator in an isothermal liquid system

  • Library:
  • Simscape / Fluids / Isothermal Liquid / Valves / Valve Actuators

  • Proportional Valve Actuator block


The Proportional Valve Actuator block models a power-controlled actuator used in conjunction with a valve block in an isothermal network. The signal to open or close the valve is received at port A. The opening distance for a connected valve is returned as a physical signal at port S.

You can adjust the opening or closing magnitude with the Actuator gain parameter. A first-order lag in time is applied to the actuation distance:



  • IG is the signal received at port A multiplied by the Actuator gain. Outside of the valve stroke limits, IG is the Valve stroke if fully extended and the negative Valve stroke if fully retracted.

  • d is the current actuator position.

  • τ is the Time constant.


This reference page is for the Isothermal Liquid library block. For the Hydraulics (Isothermal) Liquid library block, see Proportional and Servo-Valve Actuator.


To set the priority and initial target values for the block variables prior to simulation, use the Initial Targets section in the block dialog box or Property Inspector. For more information, see Set Priority and Initial Target for Block Variables.



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Physical signal that indicates valve opening or closing, specified as a physical signal. The signal is multiplied by the Actuator gain value.


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Opening distance for the connected valve, specified as a physical signal in m.


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Input signal multiplier for the valve opening distance.

Constant that captures the time required to reach steady-state conditions during actuation. This parameter impacts the response lag to the valve opening or closing signal.

Maximum opening distance of the connected valve.

Extended Capabilities

C/C++ Code Generation
Generate C and C++ code using Simulink® Coder™.

Version History

Introduced in R2020a