Mask and Parameters
Location of Data Parameters
Name | Description | |
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Open an existing cable case data file or use previously saved (click OK now) data for this device | Provide an existing cable data file if you want to modify an existing case or use previously saved data for this device. To open the previously saved version, click the OK button; in this case the data is saved within the device and not in a file. | |
Open an existing EMTP-V3 data file | Provide an existing EMTP-V3 (AUX) data file if you want to modify an existing old case. This device will try to translate the existing file to create a line case data compatible with EMTPWorks/HYPERSIM. The user should verify if the translation has been performed correctly by opening the cable case data file with the first option on this page. The provided myfile.data will be converted to myfile.lin and can be opened using the first option on this page. | |
Run an existing cable case data file without opening its data | This option submits an existing case file directly to the Cable Data Calculation function. It can be also used to run old EMTP-V3 cases without translating them. | |
Create a new line case | This option creates a new case from scratch |
Conductor Data Parameters
Once a (new) cable case is selected (created), a new window with following parameters is open.
The data tab allows the user to specify the geometrical and electrical characteristics of the cable system. This includes the geometrical description of the cable, the electrical and geometrical data of the conductors as well as the electrical properties of the insulation material. The data information required to describe a pipe-type cable is somewhat different than the data required for a single-core coaxial cable.
Although many data fields are similar, their descriptions are presented separately to facilitate readability.
Name | Description | Unit | |||
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Cable type | Users can select their cable type from a pull-down: | ||||
Single core | To generate coaxial cables | ||||
Pipe type | To generate cable models where a metallic pipe encloses the coaxial cables. | ||||
Number of cables | Indicates the number of cables in the system | ||||
Cross-bond the Sheaths | In order to model a cross-bonded cable accurately, each major section must be modeled in detail. This means that each minor section of the cable must be modeled, and the sheath bonding and sheath grounding connections must be made explicitly using the HYPERSIM node names. Such a detailed representation can be computationally intensive because modeling short cable segments of the order of 400 meters or so, requires a very small time step (a fraction of the travel time of the fastest propagation mode). Furthermore, a number of these major sections must be connected to represent the entire cable. For example, a 12 km cable with 400 m minor sections, would require a total of 30 6-phase cable models. Nevertheless, this type of detailed representation is necessary when sheath currents and voltages have to be assessed. The detailed representation of each minor section of a cross-bonded cable is in some ways analogous to modeling a transposed overhead transmission line by representing each transposition section explicitly, and connecting the sending and receiving node names accordingly with HYPERSIM node names. In the case of transmission lines, this situation can be approximated by assuming that the line is balanced, and using a single line where the elements of impedance and admittance matrices have been averaged to account for the effect of transposition. A cross-bonding option is available in the Cable Data device to provide this type of approximation. If “Cross-bond the Sheaths” is selected, then the elements of the impedance and admittance matrices of the cable are averaged to reflect the effect of cross-bonding. The grounding of the sheaths is then controlled using the KPH parameter in the "Conductor data" table. Setting KPH = 0 for the sheaths, is equivalent to assuming that the sheaths are continuously grounded (at zero potential throughout the entire cable length). In this case, the sheaths can be eliminated and a three-conductor approximation of a cross-bonded cable is obtained. This three-conductor approximation compares quite favorably with the detailed modeling of each minor section of a cross-bonded cable, and it is ideally suited for switching transient studies of cross-bonded cables, because of its computational speed and accuracy. | ||||
Single core | The general structure of this type of cable system is shown in the following figure. | ||||
Cable number | Given in increasing order for the entire cable system | ||||
Number of conductors | Indicating the number of concentric tubular conductors in this cable. For example, a cable with 3 conductors: the core, the sheath and the armor. | ||||
Vertical Distance | Depth (see VER-1 in Figure shown above) measured from the center of this cable to the earth's surface. This is a positive number. | m | |||
Horizontal Distance | Measured from the center of this cable to an arbitrary point of reference (see HRZ-1 in Figure shown above). | m | |||
Outer Insulation Radius | Indicating the outside radius of the insulation layer surrounding the cable. Use 0 if there is no surrounding insulation. This is the ROUT variable in the following figure. | m | |||
Conductor insulator data | This section describes the tubular conductor and their surrounding insulation ordered from inside out (the core conductor comes first, followed by sheath, etc.). The required data for each conductor is: | ||||
Cable number | Given in increasing order for the entire cable system | ||||
Conductor number | The term conductor is used to designate both conductor and insulator data | ||||
Inside Radius Rin | Inside radius of the conductor | m | |||
Outside Radius Rout | Outside radius of the conductor | m | |||
Resistivity Rho | Resistivity of the conductor | Ω-m | |||
Relative Permeability MUE | Relative permeability of the conductor | ||||
Insulator Relative Permeability MUE-IN | Relative permeability of the surrounding insulation | ||||
Insulator Relative Permittivity EPS-IN | Relative permittivity of the surrounding insulation | ||||
Insulator Loss Factor LFCT-IN | Loss factor of the surrounding insulation | ||||
KPH | Phase-number of the conductor. Conductors of all cables must be given phase numbers starting from 1, with no gaps in phase numbering. For example, for a three conductor cable KPH = 1, 2, 3 is a legitimate numbering arrangement, while KPH = 1, 3, 4 is not. Conductors with KPH = 0 will be grounded and all conductors with identical phase numbers will be bundled into a single equivalent conductor. The order of conductors in the Model Data File will be made according to the sequence defined by KPH. | ||||
Pipe-Type cables | Beside the two data sections of the single-core cables, the pipe-type system requires an extra section describing the geometrical and electrical property of the pipe. Since the individual cables are the same as in single-core system, the conductor and insulator data definition is the same as above. | ||||
Cable number | Given in increasing order for the entire cable system | ||||
Number of conductors | Indicating the number of concentric tubular conductors in this cable. For example, this number is 3 for a cable with core, sheath and armor. | ||||
Distance from center of pipe | The distance measured from the center of this cable to the center of the pipe. See variable Dist in Figure above. | m | |||
Position Angle | The angle measured from the line joining the center of this cable and the center of the pipe to an arbitrary reference axis. See variable ANG in Figure above. | deg | |||
Outer Insulation radius | Indicating the outside radius of the insulation layer surrounding the cable. See variable ROUT in Figure above. | m | |||
Geometrical pipe data | The geometrical data variables are shown in the figure above. | ||||
Inside radius of pipe (Rin) | Inside radius of the pipe | m | |||
Outside radius of the pipe (Rout) | Outside radius of the pipe | m | |||
Outside radius of tubular insulator (Rext) | Outside radius of the tubular insulator surrounding the pipe | m | |||
Vertical distance (depth) | Vertical distance (depth) of the pipe's center from the surface of the earth (Vdpth) | m | |||
Phase-number of the pipe (zero if it is grounded) | variable KPH | ||||
Electrical data of the pipe | The electrical data section of the pipe is self-explanatory. |
Model Parameters
Name | Description | Unit | |||
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Select model | The Cable-Model module can produce various cable models for time-domain studies. However, only the CP and Wideband cable models are currently implemented in HYPERSIM. Therefore, the documentation presented in this table will be only focused on these models. | ||||
FD | Frequency dependent cable model (not implemented in HYPERSIM) | ||||
CP | Constant-parameter cable model | ||||
Exact-PI | Exact frequency domain representation of a cable at a given frequency () | ||||
Scan | Cable model parameters are calculated at given frequencies. No model is generated. | ||||
Wideband | Wideband cable model | ||||
FD | This produces data for a cable model that is not implemented in HYPERSIM. Thus, is not covered in this documentation. | ||||
CP | The CP model (constant parameter cable model) assumes that the cable parameters R, L, and C are constant, and they are calculated at a user-supplied model frequency. This model considers L and C to be distributed ("ideal cable") and R to be lumped at three places (cable ends and cable middle). The shunt conductance G is assumed to be zero. Taking into account the frequency dependence of the cable parameters (as modeled by the Wideband model) is an important factor for the accurate simulation of transients. However, the CP model is computationally faster and it is generally used as an alternative to model secondary lines or cables. The only type of matrix that can be calculated for this model is the Real Ti . It is evaluated at the entered “Model frequency”. After entering all required data, the Model Data Calculation Function can be invoked from the “Save and run this case” data tab to generate the model data file. The model can be used with the CP line models (CP m-phase components) by selecting the model data file (also called “pun file”) through the “Load data file” option in the device data. Note that the number of phases of the selected CP line should correspond to the number of phases of the model generated in the pun file. The format of this file can be found in the documentation of the CP m-phase device. | ||||
Exact PI model | This produces data for a cable model not implemented in HYPERSIM. Thus, it is not covered in this documentation. | ||||
Scan (No model) | This selection is for the Scan option where cable parameters in either phase, modal or sequence quantities are computed at the specified frequencies. Results are shown in the output file. No model is generated | ||||
Wideband | This model represents the true nature of a transmission line by modelling the phase line parameters as complex distributed and frequency dependent. It is required to specify the 'Frequency range' for which the line propagation function and characteristic impedance are synthesized | ||||
Frequency range | The Frequency range represents the frequency band for the fitting of the line characteristic admittance and propagation function. The data fields required for this option are self-explanatory. |
Cable Length Parameters
Name | Description | Unit | |||
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Cable length and earth resistivity | The variables to set in this tab are: | ||||
Cable length | Length of the cable | m | |||
Earth resistivity | Value of the earth resistivity | Ω-m | |||
Earth relative permeability | Value of the earth relative permeability | ||||
Conductance breakpoint frequency (FG0) | Breakpoint frequency (FG0) of the shunt conductance for all insulating layers. For all insulators, the shunt conductance G is described with the following function of frequency: G = 2pi (FG0 + Frequency) * Loss Factor * Capacitance. | Hz |
Output Options Parameters
Name | Description | Unit | |||
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Special output options | The variables required for these settings are self-explanatory. | ||||
Extra output options |
Save and run this case
Name | Description | Unit | |||
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Options for saving this case | Before choosing to run this case, the user must provide a valid Case Data File identification which is the model identification and the device name.
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Current Case Data File name | Enter a unique name to save the model. | ||||
Run this case to create a model data file for the selected cable model | Select this option if you want to generate line model data. When you click OK, HS will start a separate Cable DATA calculation function for generating cable data. |
Ports, Inputs, Outputs and Signals Available for Monitoring
Ports
None
Inputs
None
Outputs
None
Sensors
None
Example
Example
Next Figure shows a sample case of complete cable and conductor data for single-core. The data case contains three identical single-core cables, each one has two conductors.
The complete layout is shown in next. Only the outside radius of the conductors and the outer insulation radius are shown in this figure. Each conductor is associated with a non-zero phase number, thus the generated model for this example will have 6 different modes (6 wires).