Lead-Lag Filter
Implement first-order lead-lag filter
Library
Simscape / Electrical / Specialized Power Systems / Control / Filters
Description
The Lead-Lag Filter block implements the following transfer function:
where
This type of filter is used mainly for implementing lead-lag compensation in control systems. The key characteristics of the Lead-Lag Filter block are:
Input accepts a vectorized input of N signals, thus implementing N filters. This feature is particularly useful for designing controllers in three-phase systems (N=3).
The same block is used for continuous or discrete model. Changing the sample time Ts from 0 to a positive value automatically discretizes the filter, and vice versa.
Filter states can be initialized for specified DC inputs and outputs.
Parameters
- Time constant T1 (s)
Specify the filter time constant(s) T1 in seconds. Default is
5e-3
.- Time constant T2 (s)
Specify the filter time constant(s) T2 in seconds. Default is
20e-3
.- DC initial input and output
Specify the DC initial value of input and output signals. If the input signal is vectorized, specify a 1-by-N vector, where each value corresponds to a particular input. Default is
0
.- Sample time
Specify the sample time of the block, in seconds. Set to 0 to implement a continuous block. Default is
0
.
Characteristics
Direct Feedthrough | Yes |
Sample Time | Specified in the Sample Time parameter Continuous if Sample Time = 0 |
Scalar Expansion | Yes, of the parameters |
States | One state per filter |
Dimensionalized | Yes |
Examples
The power_LeadLagFilter
example
shows two uses of a vectorized Lead-Lag Filter.
The model sample time is parameterized with variable Ts (default value Ts = 50e-6). To simulate continuous filters, specify Ts = 0 in the MATLAB® Command Window before simulating the model.
Version History
Introduced in R2013a