WOLFRAM SYSTEM MODELER

SMTH3

Third-order exponential smoothing

Diagram

Wolfram Language

In[1]:=

SystemModel["SystemDynamics.Functions.SMTH3"]

Out[1]:=

Information

This is a third-order exponential smoothing function.

In engineering terms, this would be called a third-order low-pass filter consisting of three first-order low-pass filters placed in series. The third-order filter is characterized by the transfer function:

G(s) = (1/(tau*s + 1))^3.

Each first-order filter has a time constants of:

tau = averaging_time/3.

The initial values of the outputs of each of the three first-order filters can be set. However, they can only be set together, i.e., only one parameter is provided for all three of them. By default, they assume values of zero.

Parameters (2)

averaging_time	Value: 1 Type: Real Description: Averaging time
smooth_init	Value: 0 Type: Real Description: Initial value of smoothed variable

averaging_time

Value: 1

Type: Real

Description: Averaging time

smooth_init

Value: 0

Type: Real

Description: Initial value of smoothed variable

Connectors (2)

	u	Type: RealInput Description: Input variable
	y	Type: RealOutput Description: Output variable

Type: RealInput

Description: Input variable

Type: RealOutput

Description: Output variable

Components (12)

	Smooth1	Type: Level1a Description: General System Dynamics level with no outflow
	Change_in_Smooth1	Type: Rate_1 Description: Unrestricted rate element with one influencing variable
	source	Type: Source Description: This is the (dummy) source model of System Dynamics
	ch_in_smooth1	Type: Change_In_Smooth Description: Smoothing rate
	Smooth2	Type: Level1a Description: General System Dynamics level with no outflow
	Change_in_Smooth2	Type: Rate_1 Description: Unrestricted rate element with one influencing variable
	source1	Type: Source Description: This is the (dummy) source model of System Dynamics
	ch_in_smooth2	Type: Change_In_Smooth Description: Smoothing rate
	Smooth3	Type: Level1a Description: General System Dynamics level with no outflow
	Change_in_Smooth3	Type: Rate_1 Description: Unrestricted rate element with one influencing variable
	source2	Type: Source Description: This is the (dummy) source model of System Dynamics
	ch_in_smooth3	Type: Change_In_Smooth Description: Smoothing rate