blockDiscreteTimeSlewRateLimiter
Extends from Modelica.Blocks.Interfaces.DiscreteSISO (Single Input Single Output discrete control block), TransiEnt.Basics.Icons.DiscreteBlock.
Information
1. Purpose of model
The SlewRateLimiter block limits the slew rate of its input signal in the range of [Falling, Rising].
To ensure this for arbitrary inputs and in order to produce a differential output, the input is numerically differentiated with derivative time constant Td. Smaller time constant Td means nearer ideal derivative.
Note: The user has to choose the derivative time constant according to the nature of the input signal.
2. Level of detail, physical effects considered, and physical insight
(Purely technical component without physical modeling.)
3. Limits of validity
(Purely technical component without physical modeling.)
4. Interfaces
(no remarks)
5. Nomenclature
(no elements)
6. Governing Equations
(no equations)
7. Remarks for Usage
(no remarks)
8. Validation
Tested in check model "TestDiscreteTimeSlewRateLimiter"
9. References
(no remarks)
10. Version History
Model created by Pascal Dubucq (dubucq@tuhh.de), Aug 2014
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| SI.Time | samplePeriod (from DiscreteBlock) | Sample period of component | |
| SI.Time | startTime (from DiscreteBlock) | 0 | First sample time instant |
| Real | Rising | 1/60 | Maximum rate of change of input when rising |
| Real | Falling | -Rising | Maximum rate of change of input when falling |
| Real | Max | 1/Modelica.Constants.eps | Can be used to limit absolute value as well as slew rate |
| Real | Min | -Max | Can be used to limit absolute value as well as slew rate |
Connectors
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Blocks.Interfaces.RealInput | u (from DiscreteSISO) | Connector of Real input signal | |
| Modelica.Blocks.Interfaces.RealOutput | y (from DiscreteSISO) | Connector of Real output signal |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| Real | y_rcbl_by_rate_max | Reachable output in next step if input is only limited by rising rate | |
| Real | y_rcbl_by_rate_min | Reachable output in next step if input is only limited by falling rate | |
| Real | y_limited_by_rate | Limited value without absolute value limit |
Revisions
| Revision | Date | Author | Comment |
|---|---|---|---|
| 4954 | 2012-03-02 | A. Haumer & D. Winkler | Initial version based on discussion in #529 |