138kV/13.8kV Substation Design Project Team : sdmay18-06 Advisor : Professor Venktaramana Ajjarapu Client : Black & Veatch Project Website : http://sdmay18-06.sd.ece.iastate.edu/ Introduce team members - Andrew, Brent, Eric, Gavin, Terry Terry Client contact person: Adam and cole

The Team Andrew Brown: AutoCAD Director, Design Engineer Gavin Christenson: Chief Design Engineer Eric Fritz: Meeting & Communication Director Brent Hines: Project Lead, Materials, Design Engineer Weng Hoong Loo: Scheduling & Resource Manager, Design Engineer Andrew Brown Brent Hines Gavin Christenson Eric Fritz Weng Loo (Terry)

Project Plan

Problem Statement - Safe Distribution of Electricity Purpose Design substation protection and control systems for Black & Veatch Safely turns 138 kV into 13.8 kV Protection from internal and external factors Benefits Decreases grid strain through localized distribution Safely distribute electricity to consumers Brent

Substation Design A Substation is consisted of various electrical equipment which either steps- up or steps-down voltage for transmission or distribution in order to prevent power losses as well as providing power at a safe level for consumers. Terry

Substation Protection and Control Main Equipments Power Transformers Current Transformer Circuit Breakers Disconnection Switches Circuit Switches Lightning arresters Control House Gavin

Deliverables Protection and Control Design One Line Diagram Key Protection Plan Three Line Diagram AC Schematics Protection and Control Schematics Communication Schematics Relay Schematics Wiring Diagram and Panel Layout Connection Diagram Physical Layout Control House Layout Engineering Management Service Project Budget Project Schedule Weekly Status Report Project Review Meeting Final report and presentation Eric These are the major milestones, and overarching tasks of the project. The next slide shows the number of items each of these requires. For example, there are 9 documents in the protection and control schematics. For weekly status reports a meeting agenda containing the questions that will be answered and the documents that will be covered must be submitted before our weekly hour long meeting. After the meeting's completion summary of the meeting is submitted.

Project Timeline Eric This is our Gantt chart. As you can see the majority of the tasks are the creation of design documents, shown in orange, yellow and green. We will be finishing the project with a presentation at Black and Veatch.

Project Milestones Eric This is our Design Document Database and it is a method of organizing and easily understanding what we have accomplished and what is left to be accomplished. It is also a reference to relate the drawing number to the title allowing to intuitive formal discussion.

System Design

Project Resources Software Tools AutoCAD Design Resources Black and Veatch Design Team Industry Design Guidelines External Reference Material Eric Fritz NEC AutoCAD has been an excellent resource, which we have used throughout the first semester, that allows us to quickly and freely implement updates the design documents. Black and Veatch has been the driver of our progress on creating accurate and clean drawings. For design guidelines we utilized the Project Scope which details the protection and control equipment for the substation. Some external reference material has been a reference guide we created that includes the ANSI ID for every device that is included in our design schematics. Another reference is the HV Substation Design: Applications and Considerations created by Dominik Pieniazek. This document rapidly familiarize us with the components and design of a substation.

Process Flow Eric Talk more on how we create the document Based on previous documents, standards, requirements Instead of previously created document, review high level drawing > create more detail low level drawing to match the specifications outlined for our unique substation https://docs.google.com/document/d/1eQjgKLGdAJGMydu4HHnbkGhs3oN6f4eZtLNn_AhEiUo/edit

Testing Plan Continuous process where works done will be reviewed by Black & Veatch Design Team Calculations Max Power at various parts of the substation using the CT ratios greater than 25% listed Peak AC and DC voltage of the control house Next Semester Testing various safety parameters Brent 25kA simulation in discussion Max power calculations for transformer can withstand temporary overloading

Technical Challenges Understanding the project material: - Learning how a substation operates Revisions implemented on the drawings Purpose of different equipment Protection Schematics Team Website Construction Learning how a substation operates and why we are using the specific equipment Terry

Overcoming Technical Challenges Overcoming the challenge: Deep Diving into the drawings Technical Manuals Seeking advice from experts B&V experts, Project Advisor, Online Resources External Resources National Electrical Code IEEE Substation Guidelines Terry

One Line Diagram

Overview of One line Diagram Brent

High Voltage (HV) Side 138kV Brent

Low Voltage (LV) Side 13.8kV Brent

Overview of Key Protection Plan HV Side 138kV Bank Relays LV Side 13.8kV Andrew

HV side 138kV Andrew Out to 13.8kV Bus

LV side 13.8kV Into 13.8kV Bus Andrew

Bank Relay In from 138kV Bus In from 13.8kV Bus In from Feeder End Protection Equipments in the control house Andrew In from Feeder End

Three Line Diagram

AC Schematics 1 (HV Side) Out to 13.8kV Bus Gavin

AC Schematics 2 (LV Side) Into 13.8kV Bus Gavin

Conclusion

Future Plans Panel Layout Substation Layout Relay Diagrams Material List Wiring Diagrams Final Presentation for Black & Veatch Andrew

Acknowledgement In conclusion, we would like to extend a, “thank you”, to the following resources for their help throughout this project: Adam Literski and Cole Beaulieu, Black & Veatch Dr. Ajjarapu, Iowa State University Thank you for your attention. Andrew

Extra Resources

Purpose of CT What is the purpose of multiple CT’s on both sides of the 138/13.8 transformer? Monitoring/measuring purposes, tell which side of transformer has a fault, why/where/how fault occurred What is the difference in the ways the CT’s of different ratios are used? Different ratios connected to different equipment, Some equipment needs more precise measurement, and therefore smaller ratio e.g. use 600-5 instead of 2000-5 for more sensitive equipment What should we make of the absence of CT’s around the 240/120 transformer (and the absence of a lightning arrester on the low voltage side)? Secondary transformer for control house wall outlets, Lower voltage does not require as much protection

Function of each Equipment

Transformer Purpose Types Change voltage from one level to another Symbol Purpose Change voltage from one level to another Regulate voltage level. Types Generator Step-Up (GSU) transformers Step-down (to load) distribution transformers SUBSTATION DESIGN

Circuit Breaker Purpose Types Detect faults and interrupt current flow Symbol Purpose Detect faults and interrupt current flow Types Oil, air, SF6 gas, vacuum SUBSTATION DESIGN Operation of the circuit breakers is initiated by: utilizing dc circuits manually operating a switch remote operation of supervisory control equipment by relays that automatically recognize predetermined conditions or electrical failures in the system.

Disconnect Switches Purpose Types Symbols Purpose Equipment usually connected in series with disconnect switches to isolate lines and equipment for maintenance Types Vertical break, Center break, Side break, Double end break, Pantograph, Motor-operated SUBSTATION DESIGN

Lightning Arresters Purpose Protect substation equipment and electric system from lightning strokes Installed near power transformers Symbol SUBSTATION DESIGN The arrester provides a low-impedance path to ground for the current from a lightning strike or transient voltage and then restores to a normal operating conditions. When a high voltage (greater than the normal line voltage) exists on the line, the arrester immediately furnishes a path to ground and thus limits and drains off the excess voltage. The arrester must provide this relief and then prevent any further flow of current to ground. The arrester has two functions; a) it must provide a point in the circuit at which an over-voltage pulse can pass to ground and, b)to prevent any follow-up current from flowing to ground.

Circuit Switcher Purpose Types Symbol Purpose For switching and protection of transformers, lines, cables and capacitor banks Some models have bypass switches Types SUBSTATION DESIGN Vertical interrupter circuit switcher Horizontal interrupter circuit switcher Circuit switchers usually have SF6 type interrupters. Some circuit switchers have by-pass switches. Circuit switcher operation can be initiated by an operating switch, remote supervisory control equipment or by relays. Circuit switcher types: Horizontal and vertical interrupter 1. Vertical Circuit Switchers (CSV) Particularly used in cases of space constraints. The customer can specify whether the switches are manually operated or motor operated.   2. Horizontal Circuit Switchers (CSH, CSH-B)

Current Transformers Purpose Symbol Purpose Connected in lines to measure alternating electric current Electrical inputs for operation of protective relays and measuring instruments SUBSTATION DESIGN 1. CT is described by it’s current ratio e.g ratio 800-5 in the image. 2. Since current in the circuit is really high, a CT measures a current proportional to the one in the circuit which can be connected to measuring and recording instruments.

Voltage Regulators Purpose Symbol Purpose Provides voltage boost or buck in a system to provide a more or less voltage constant voltage as the amount of the load. SUBSTATION DESIGN Found at substations and on distribution lines A regulator is an autotransformer with adjustable taps that is normally capable of adjusting the voltage by ±10%. An autotransformer is a winding on a core with a tap off the winding that provides voltage boost or buck. Adjusts for the voltage drop in a circuit.

Control house/Panel arrangement Purpose To protect the control equipment including panels, batteries, battery chargers, relays, meters, etc. SUBSTATION DESIGN Underground and overhead conduits and control wire are installed to connect the controls of all the equipment in the substation to the control panels normally installed in the control house.