Short manual for program TLZ

Multiconductor Transmission Line Impedance (Z) calculation program

developed by M. Khapaev, MSU, mkhap@pn.npi.msu.su

How to start the calculations and obtain the results

Print in command line:

TLZ infile

where infile is the path to input file. The extension of input file usually is dat. The input file is the ASCII text file and can be prepared by any text editor.

All output can be found in file TLZ.LOG .

The list of commands of input file

The input file consists of strings. Each string presents a command or a comment. The commands have the form

command_name arg arg .... arg [ arg arg

where arg is a number or a text or a character. The values after square bracket “[“ are optional.

The delimiters for arguments are space, equality (=), comma (,) or tabulation.

The commands are case insensitive.

The order of commands (except special cases) is not valid.

The unknown or error commands are ignored.

For many commands the default values exist.

The empty strings in the input file are ignored. The double space at the beginning of a string means the input file comment.

Cross-sections of the conductors consist from boundary elements. Boundary elements are oriented and conductor body need to be placed from left side of the element.

For better precision and numerical stability the length units need to be taken in the way that coordinates should be of order of magnitude of 1. In other words if the size of cross-section essentially is in mm then do not present input data in m.

The commands are:

Description of single parameter commands

• сс any text;
• ah=value ; Real value. Step size. Default value is 1;
• lambda=value ; Real value. Default London penetration depth for superconductors. Predefined value is 0.1um (niobium);
• sigma=value ; Real value. Default conductivity. Predefined value is 56 ms/m (copper);
• frequency f [ units; f- frequency value; units can be hz, khz, mhz, ghz; Default value 1 mhz;
• lengthunit unit ; unit can be m, cm, mm, um. Default is um ;
• conductanceunit unit ; unit can be ms/m or s/m ;
• symmetry on/off ; Mirror image switch for groundplane simulations ;
• variables phases/voltages ; Default is phases (for superconductors);
• gridsize val ; val is real value. If all geometrical coordinates (except London penetration depth) are presented via dimensionless unit then val is the value of this length unit in chosen length units (um, mm, cm or m). This command is useful if input data is presented as DXC file.

Command <patch>

For each conductor material properties, conductivity and London penetration depth need to be specified. It is done by use of command patch. The format of this command:

patch n w sigma [ lambda [ mu

First parameter n specify the number of material patch. Second parameter w define type of the conductor, superconductor or normal conductor. w can be <sc> or <nc> (strings).

Patch with number 0 is default and contain default or predefined values. Conductors can be multiconnected and can contain component parts with different conductivity and penetration depth.

sigma , lambda and mu are normal conductivity, London penetration depth and relative manetic permettivity. The default value of permettivity is 1.

Command <pt>

In order to define the boundary of conductors it is possible first to define basic points of the cross-sections of conductors. It need to be done by use of the program pt:

pt i x y

where integer i is the number of the point (is necessary for further references) and (x,y) are the coordinates of the point.

Command <line>

Define boundary element - segment of strait line. Format:

line nCond n0 n1 [npatch=0

where all parameters are integer. nCond is number of conductor, n0 - origin basic point of line, n1 - end basic point, npatch - number of material patch (default is 0). Basic points need to be defined by the command pt.

Command <curve>

Define quadratic boundary element with direction from n0 to n1. Format:

curve nCond n0 n1 n2 [npatch=0

where all parameters are integer. nCond is number of conductor, n0 - origin basic point of line, n1 - middle point, n2 - end basic point, npatch - number of material patch (default is 0). Basic points need to be defined by the command pt.

Command <circle>

Define boundary element - circle. Format:

circle nCond n0 R sign [npatch=0

where integer nCond is number of conductor, integer n0 - basic point for centre, R - radius, sign is char and can be + or - , npatch - number of material patch (default is 0). Basic point need to be defined by the command pt. sign define the direction of the element and + is for anti-clockwise direction.

Command <el>

Instead defining basic points it is possible define boundary element by single command. Format:

where iform=0 is for segment, iform=1 is for curve and iform=3 is for circle.

Command <rect>

Define boundary element - rectangle. Format:

rect a b c d [nCond=0 [npatch=0

where rectangle is [a,b]*[c,d], integer nCond is number of conductor (default is 0), npatch - number of material patch (default is 0).

Command <pl>

See command DXC.

Command <DXC>

Format:

DXC dxcfilepathnameplusextension

ACAD drawing can be exported in form of DXC file. DXC file contain polylines which are boundaries of conductors. Each polyline has integer parameter called elevation. We use this parameter as identifier of the polyline. Then numbers of conductors and material patches can be assigned with the command pl:

pl i nCond npatch=0

where i is the identifier of the polyline.