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| Vectorized | |
| in the palette | on the schematic |
The block allows you to plot the selected amplitude-phase frequency characteristics of a dynamic object (of a link or of a system).
For linear dynamic objects, the implemented numerical algorithms make it possible to determine the amplitude-phase frequency characteristics directly using well-known formulas. To calculate the characteristics of nonlinear objects, automatic linearization of the object in a small neighborhood of the stationary state is preliminarily carried out.
The calculation results are displayed on a graph of the dependence of the selected characteristics on the frequency, which is called by double-clicking on the block with the left mouse button.
Прим.: if there is negative feedback in the model, then the block will perform calculation for the closed system. To obtain the frequency characteristics of an opened system, it is necessary to disconnect the feedback.
Input Ports
| Name | Description | Communication line type |
|---|---|---|
| in | Port for connection of the output signal of the object under study | Mathematical |
| out | Port for connection of the input signal of the object under study | Mathematical |
Output Ports
The block has no output ports
Properties
| Title | Parameter | Description | By default | Data type |
|---|---|---|---|---|
| Types of calculated characteristics | chartypes | Opens access to the "Select objects from the list" window, in which, in the "Receiver" field, a list of characteristics for display on the plot is determined ("D-split", "Im(w)", "Re(w)", "AFC", "Nyquist Locus", "Popov Locus", "LMD", "PFC"). The characteristics added from the "Source" field to the "Receiver" field will be plotted. Adding and removing elements from the "Receiver" field is done using the arrow buttons | AFC | Set |
| Show system poles | showpoles | Allows you to display the poles of the dynamic system on the complex plane | None | Binary |
| Show system zeros | showzeros | Allows you to display the zeros of the dynamic system on the complex plane | None | Binary |
| Starting circular frequency, 1/sec | wstart | Indicates the beginning of the circular frequency range in which the frequency response will be calculated | 0.5 | Real |
| End circular frequency, 1/sec | Wend | Indicates the end of the circular frequency range in which the frequency response will be calculated | 20 | Real |
| Number of output points | ptcount | Number of values of circular frequencies within the range for which the characteristic values will be calculated (number of plot points) | 500 | Integer |
| Relative increment for Jackobian | dJotn | The value used for carrying out linearization of nonlinear objects | 0.001 | Real |
| Absolute increment for Jackobian | dJabs | The value used for carrying out linearization of nonlinear objects | 1E-6 | Real |
| Characteristics calculation mode | ffdcalcmode | It allows us to determine a moment of calculation: during schematic initialization, when the final calculation time is reached or with a preset step (i.e. "At the beginning of calculation", "At the end of calculation", "With a preset step") | At the beginning of calculation | Enumeration |
| Characteristics calculation step, sec | ffdtimestep | The value of the time step with which the characteristics are recalculated. The property is used if the "With a preset step" mode is selected | 0 | Real |
| Reduce degree of the numerator and the denominator polynomials | ReduceDeg | Checkbox to activate degree reducing of the numerator and the denominator polynomials | None | Binary |
| Absolute comparison accuracy of the roots of the numerator and the denominator when reducing degrees of polynomials | ReduceTol | Absolute allowable error in comparison of the roots of the numerator and the denominator when reducing degrees of polynomials. This option is available in the property "Reduce degree of the numerator and the denominator polynomials" | 1E-5 | Real |
| Show design system parameters | showtransfunc | Allows you to display the calculated parameters of the dynamic system: numerator and denominator polynomials, zeros, poles and matrices of the equations of state of the dynamic system | None | Binary |
| Design system parameters | System parameter group that is displayed when the "Show system design parameters" property is activated | |||
| Numerator W(s) | Ns_out | Array of coefficients bi of the numerator polynomial of the form N(s)=b0sm+b1sm-1+...+bm starting from b0 | [[]] | Matrix |
| Denominator W(s) | Ns_out | Array of coefficients ai of the denominator polynomial of the form L(s)=a0sn+a1sn-1+...+an starting from a0 | [[]] | Matrix |
| Zeros (roots of equation N(s) = 0) | Zeros_out | Array of zeros of the transfer function (the roots of the characteristic polynomial in the numerator of the transfer function) | [[]] | Complex matrix |
| Poles (roots of equation L(s) = 0) | Poluses_out | Array of transfer function poles (characteristic polynomial roots in the transfer function denominator) | [[]] | Complex matrix |
| Matrix A (eigenmatrix) | A_out | Value of the eigenmatrix of the state equations system | [[]] | Matrix |
| Matrix B (input matrix) | B_out | Value of the matrix of inputs of the state equations system | [[]] | Matrix |
| Matrix C (output matrix) | C_out | Value of the matrix of outputs of the state equations system | [[]] | Matrix |
| Matrix D (detour matrix) | D_out | Value of the detour matrix of the state equations system | [[]] | Matrix |
Прим.: in this block, the values of the circular frequency ω having a units 1/sec (rad/sec) are used. Hz is not used.
Прим.: property window is opened via context menu of the block
Parameters
| Title | Parameter | Description | Data type |
|---|---|---|---|
| X values | X | Circular frequency matrix for selected characteristics at each output point | Matrix |
| Y values | Y | Matrix of calculated values of selected characteristics at each output point | Matrix |
Examples
Examples of block application:
