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lbl-srg / modelica-buildings

Modelica Buildings library
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add ramp model for signals #17

Closed mwetter closed 4 years ago

mwetter commented 11 years ago

When switching a component on or off, such as a pump, the solver can have difficulties in finding a solution to nonlinear systems of equations in large fluid flow network. As a work-around, a first order differential equation is often used.

As an alternative approach, a block that limits the rate of change of its output signal should be developed, tested with large system models, and if successful added to the library.

For a step input from a to b, this block should output a ramp that continuously changes the output between a and b.

mwetter commented 4 years ago

This can be done using Buildings.Controls.OBC.CDL.Continuous.SlewRateLimiter.