The CART SoftwareDeveloped by Ciber Terrasoft (Pty.) Ltd.

Overview

• Introduction to product

• Introduction to company

• Evaluation of product

• Walk through of a simple example

• Outputs/Retports/etc

• Data Capturing

What is CART?

• CART is a CAD-based integrated design tool to support the detailed design of MV and LV distribution networks.

• Using CART:-– Design distribution networks,– Analyse network performance,– Produce final construction drawings,– Generate Bill of Materials and Reports.

What is CART? (cont….)

• CART is a productivity tool to support the detailed design of LV distribution networks

• CART was developed at Wits University in close collaboration with Eskom over the past 12 years

• When using CART the designer focuses on engineering- the computer does all of the tedious and repetitive tasks

What is CART? (cont…)

• CART supports all aspects of the distribution design workflow

• CART is used by Eskom and by consulting engineers in South Africa and in other countries

What is Ciber Terrasoft?

• Ciber Terrasoft (Pty) Ltd (“Terrasoft”) was set up in 1998 to support CART

• Terrasoft has developed over 12 years of experience and expertise in the specialised field of software tools to support electrical distribution engineering

What is Ciber Terrasoft?(cont….)

• Terrasoft supports CART, offers training and specialised software customisation and development

• Terrasoft works in alliance with other software development companies

• Offers various services around the area of network data capturing

Evaluation of CART

• From 2000 to 2001 Eskom DT and Terrasoft undertook a detailed evaluation of the CART software

• CART was found to do the following:– increase engineering productivity by

three times, – eliminate errors and – improve the overall quality of designs.

Evaluation of CART

• 2002 winner of a prestigious Award in South Africa for CART’s energy saving capability.– (The Award is sponsored by Eskom & endorsed

by the Department of Minerals & Energy)

• In South Africa, CART could save:- consulting engineers R2 million/annum in improved

productivity; Eskom R180 million/annum in reduced construction

costs; 17GWh per annum in reduced network losses.

A Walk through example

• CART works within a 3rd party CAD program (front-end) called MicroStation developed by Bentley USA.

• Currently uses Microsoft Access™ database for storing network info.

• Uses Microsoft Excel™ for costing the project, BOM, etc.

Initial title screen

This example uses screen captured images to portray concepts. The first step is create a brand new project using wizard

• Select dgn drawing on which the new distribution network will be placed/designed.

Select Drawing

• Select only the required conductor types for this project.

• Additional conductor types can be added to the library

Select conductors/cables

• Select only the required transformer types for this project.

• Additional transformer types can be added to the library

Select transformers

• Select material for various applications eg:

• Type of MV pole

• Type of LV pole

• Types of pole-top conductor supporting structures for various stringing angles

Select default materials

• Calculations done only for LV portion of the network.

• One of the methodology used is Herman-Beta method developed by Prof. Ron Herman

Select calculation parameters

Design Environment

Now that the project has been configured, the user is presented with the design environment.

Identify consumer locations

The consumer locations are identified (shown by the purple circles) and entered into a database so that the stand number, voltage, phasing info, etc can be tracked.

This is a zoomed in view of the bottom left of the township. The stand boundaries are indicated by the black lines while the road reserve is indicated by the brown.

Select transformer typeZoom into an area and begin the procedure to define a transformer zone. First select the size and rating. Then select all the other devices such as fuses and the like that need to be installed along with the transformer.

Draw transformer zoneThe transformer zone is drawn as indicated by the blue line. The stands are automatically counted and presented in a window.

Based on the estimated loading of the transformer the zone can be resized until the desired transformer loading is achieved.

Optimum transformer locationOnce transformer zone is finalised, CART will place the transformer at load centroid of this zone. The transformer needs to be moved to practical location.

Optimum transformer location

Move the transformer to a practical location which can be used to service everyone in the zone

Add LV feeder

A construction line is used to indicate the route that the conductor is to follow.

Poles are placed whenever there is a change in direction. Poles can also be placed along the route at certain places if required. CART has a feature for determining optimum spans.

The current span (distance from the most recently placed pole) is displayed in metres to guide the designer with pole placement.

The total distance from the start of the construction line is also indicated. In this case that is the total distance from the transformer.

Add LV feedersOnce the conductor route is specified using the construction line, poles are inserted wherever they are required along the route. This would be in addition to the poles specified by the designer.Conductor (feeder) segments

are then added along the route as indicated by the red lines.

Service feeders are automatically extended from the poles along the route to the nearest consumer.

Add LV feeders

In a similar manner, the remaining feeders can be added, until all the consumers are connected up.

Once the transformer zone is completed the calculations can be done. The first thing to do is the Auto Phasing. This optimally assigns the loads to the available phases so that the transformer is evenly balanced.

Now the voltage calculations can be done. The values are calculated and displayed on the screen next to each consumer. Real feeder and service distances are used for the calculations.

Calculations

The voltage texts are colour coded to indicate the tolerance. The text in green is within 5% of nominal, while the text in yellow (not legible) is within 10%. The voltages in red have exceeded the tolerance and corrective action is required.

Voltage can certainly be improved by changing the tap setting on the transformer (straight forward). It can also be improved by upgrading the feeder section to a larger conductor as shown in the next slide.

Re-Calculation

Though the voltages are not legible in the image, one can see that they are yellow in colour which is acceptable. In this manner one could go about adjusting the network until all the voltages are acceptable.

Please note that the voltage text colours and the percentage tolerances are completely configurable to suit your needs.

Alternatively, the tap setting on the transformer can be increased by editing the transformer’s properties. One can also see the phase balancing, voltages at the secondary bushings, currents, losses, etc

This is the phasing information in the order of Red White and Blue. This indicates that there are 4 customers on the blue phase.

This is the pole number. The first 2/3 digits indicate the transformer number. The alphabet indicates the feeder name. The last two digits indicate the pole number along that feeder. In this case, this is the first pole along the E feeder.

Pole labeling

This is the 5-character pole code that indicates exactly all the materials that are required at this location. CART generates a corresponding table that would enable one to decipher this code.

Once the the zone layout is completed to the designer’s satisfaction the pole labels can be determined. CART examines the various structures required, angles, etc, to determine all the materials required. All the poles are also automatically numbered.

Adding MV feeder

CART allows the MV feeder to share poles with the LV feeder which can reduce infrastructure costs. If any of these poles are moved then both the MV and LV feeders will be modified together.

MV source indicating the T-off point from which the MV feeder will run to the township

The green colour line indicates the route that the MV feeder travels to the transformer in this township.

Adding the Drawing KeyThe drawing key allows one to decipher the 5-character code that has been placed on all the poles.

Costing the project

This is a summary sheet for all the costs associated with the project. Note that the costs are always broken down per transformer zone. The detailed tabs of the spreadsheet will follow.

This lists all the conductors and their lengths as used in the project. Note that the costs are always broken down per transformer zone.

This lists all the service conductors and their lengths as used in the project. Again the costs are broken down per transformer zone.

This lists all the material structures and their costs as used in the project. Again the costs are broken down per transformer zone.

Since the network is captured in a relational database as it is drawn, it is possible to cost the project by simply extracting the information from that database.

Outputs: Construction Dwg

The customised line style indicates the conductor diameter and the number of phases. Eg 35mm2 and 2 phase.

This is a 3 phase Fox conductor.

The symbol library that CART uses and the line styles used to represent the various different conductor types can be configured as desired. Even customised line styles can be used as required by Eskom

Outputs: ReticMaster™CART can export the network to ReticMaster™ with the desired level of detail. This options exports a single zone but captures the load information at the junction or poles.

CART can export the network to ReticMaster™ with the stand and service conductor information included.

Outputs: ReticMaster™CART can export the an enitre network to ReticMaster™ including the MV. This option does not export the load information at the junction or poles.

CART can export the entire network to ReticMaster™ with the stand and service conductor information included.

Outputs: ReportsFor each transformer zone, the following network details are listed:-• Transformer loading,• Losses,• Loading on each phase,• Voltage and Current at the secondary bushings

All the customers are listed along with their details. The customer list is sorted in ascending order of the voltage

Outputs: Volt PlotsThis is a summary plot for all the feeders from the transformer.

A single plot is generated for each main feeder from the transformer

Voltage is shown on the Y-axis. The X axis intersects at the 207V point as voltages below this are unacceptable.

The X axis shows the distance from the transformer in meters.

The plot indicates the voltages for each phase using a different colour. The blue lines at the end indicate the voltage drops of the service feeders. This is just a summary plot.

The plot is for the shortest feeder on the network

The line indicates the position of the pole along the plot and displays the pole number.

Each stand number at the end of the service feeder is displayed. This allows one to identify consumers who have low voltages.

This is the plot for the longest feeder in the network. One can see that it reveals a great amount of detail.

Outputs: Line Diagram

The single line diagram is for the entire zone.

Details of the zone are shown at the top of the diagram.

For each nodes (poles), the following information is displayed:-• pole number, • minimum voltage, • the fault level and the distance from the transformer• the number of consumer allocated to the respective phases.

For each feeder, the following information is displayed:-• the feeder length• the max current and loading percentage on the conductor• the conductor type

Outputs: Project Statistics

For a project with a large number of transformers, the following statistics information is displayed for each zone:-• no. of connections,• the loading,• the length of new MV and LV feeders,• the network losses.

Some further stats is provided on the overall design. These figures are used to assess the level of optimisation that has been undertaken by the designer.

Outputs: BOM

During normal costing CART works at the structure level. Upon completion, the structures can be exploded to obtain the Bill of MaterialsThe structures can be exploded to obtain the Bill of Materials which are listed by part numbers (in this case the SAP number as used by Eskom)

Network Data Capturing

If only a CAD drawing is available then it can be converted to a CART project so that the network can simulated. Extensions and/or infills can then be planned accordingly. However, during costing only the extensions and/or infills will be considered.

Network Data Capturing

Before capturing specify the levels on which the specific information should be sought.

Specify the cell names that need to be sought when tracing the network.

Since a CAD drawing has no ‘intelligence’ associated with it CART has to identify various features and convert it to CART elements which can then be used to do a trace.

Network Data Capturing

CAD drawing has been captured into CART.

CART has captured the network by recognising the symbols and the conductor types. The previous CAD information has been replaced with the CART conductor and symbol information. One can now add infills and/or extensions to the network.

For the purpose of this demonstration, assume that the new connections as shown in the circle above have been identified.

The extended network is calculated and costed.

Extensions/Infills

It can be seen that only the extension (6 new customers) is costed. The other tabs of the cost spreadsheet are not shown.

Consider an MV/LV layout as show here

Interface with SinCal

Now seen without the cadastral map

Connect with SinCal so that the network information can be transferred.

Interface with SinCal

SinCal is brought into view with the MV network layout. The required simulations can be analysed as required before transferring the results back to CART.

Interface with SinCal

Now that the MV nominal voltages have been set at the transformers, the LV calculations must be re done so that the correct voltages for the customers can be determined.

Thank you

Should you require more information about the product or services, please do not hesitate to get in touch with us.

Ciber Terrasoft (Pty.) Ltd.Email: info@terrasoft.co.zaurl: www.terrasoft.co.zaTel: +27 (0)11 315 3837Fax: +27 (0)11 315 8332

Block B7, GreenOaks Office Park, Cnr of Gregory Ave & Bekker Street, Vorna Valley – MidrandP O Box 5705, Halfway House, 1685, South Africa.