- Transformers
- Transformer Selection and Sizing
- Ratings of Circuit Breakers
- Ratings of Isolators
- Voltage Transformer
- Current Transformer
- Low Power Current Transformers
- Standard Ratings
- Design & Calculations
- Busbar Size Calculation
- Short Circuit Current Calculation
- Capacitor Bank Size Calculation
- Cable Size Calculation
- Voltage Drop Calculation
- Useful Resources
- Substation Design - Useful Resources
- Substation Design - Discussion
Substation Design Tutorial
An Electrical Substation is an arrangement of various power components or equipment such as transformers, circuit breakers, fuses, conductors, isolators, and many more. The primary functions of a typical substation to regulate, either switch on/off power supply or change the voltage levels. Also, substations provide comprehensive protection against faults to the entire electrical power system. Hence, Electrical Substation Design is one of the most critical processes in the development of an effective power transmission or distribution system.
In simple terms, we can state that a well-designed electrical substation provides efficient, safe, and reliable power flow.
In this substation design tutorial, you will find a detailed and step-by-step guidance on how to design a substation. This tutorial covers both the conceptual as well as the practical implementation of a substation.
What is an Electrical Substation?
An electrical substation is one of the important parts of the electrical power system, it is mainly an arrangement of equipment for transforming voltage from high to low or low to high values. It also uses various control and protection devices to manage the flow of electricity through the transmission and distribution networks.
A substation basically acts as a point of interconnection between various parts of a power system such as generating station, transmission network, and distribution network.
Main Functions of a Substation
A typical substation performs the following key functions −
- Transformation of voltage from high to low or low to high value.
- Routing of electricity to various transmission circuits.
- Switching of electric power.
- Protection of power system equipment.
- Control and monitoring of power system operation.
- Management of power quality.
Types of Substations
Depending on the function performed, electrical substations can be classified into the following key categories −
- Transmission Substation
- Distribution Substation
- Switching Substation
- Converter Substation
We will discuss about all these types of substations in subsequent chapters.
What You Will Learn in This Substation Design Tutorial?
This substation design course/tutorial provides a detailed study of the following concepts −
- Electrical substation basics and their classification.
- Selection and sizing of substation components like transformers, circuit breakers, CTs, PTs, bus bar, etc.
- Process of designing substation layout and single line diagram (SLD).
- Calculating short-circuit current and load losses.
- Protection of power system using SF6 circuit breaker and other technologies.
- Practical substation design guidelines.
- Standard ratings of various substation equipment.
What This Substation Design Tutorial Covers?
The is substation design tutorial covers the following key topics which are arranged in a chronological order −
| Title | Description |
|---|---|
| Electrical Substation Basics | This chapter provides an overview of electrical substations, their classification, and components of substations. |
| Transformer Selection | In this section, you will understand the process of selecting a right transformer for the substation. |
| Transformer Sizing | This chapter provides the sizing calculation of transformer as per the system needs. |
| Circuit Breaker Ratings | In this chapter, you will learn about ratings of a circuit breaker used in substations. |
| Isolator Ratings | This chapter explains the ratings of isolators used in substations. |
| Voltage Transformer for Metering | In this chapter, you will study about voltage transformer used for metering purposes in a substation. |
| Voltage Transformer for Protection | This chapter provides the study of voltage transformer (PT) used for protection of substation electrical systems. |
| Current Transformer for Metering | In this chapter, you will get an overview of current transformer (CT) used for metering purposes in a substation. |
| Current Transformer for Protection | This chapter is about explaining the current transformers used in protection system of substations. |
| Low Power CTs | This chapter explains the characteristics of low power current transformers (LPCT). |
| Cubical Substation | In this part of the tutorial, you will learn about cubical substation, its connection to main power supply and protection using SF6 technology. |
| Standard Ratings of Substation Equipment | This chapter provides standard ratings of various substation equipment such as Metering CTs, Metering PTs, HRC Fuses, Power Transformers, Distribution Transformer, and Switchgears. |
| Substation Drawing and SLD | In this chapter, you will learn about design drawings and single-line diagrams of substation. |
| Short-Circuit Current Calculation | This section provides the engineering calculation of short-circuit current for electrical system of substation. |
| Bus Bar Size Calculation | In this chapter, you will study finding the correct size of busbar in the substation. |
| Capacitor Bank Size Calculation | In part provides calculation study of capacitor bank size used in substations. |
| Load Calculation of Transformer | In this chapter, you will study calculating load of transformer in a substation. |
| Capacitor Selection | In this chapter, you will study how to select capacitors for a substation application. |
| Load Loss Calculation of 3-Ph Transformer | This chapter provides the study of load loss calculation of a three-phase transformer used in a substation. |
| Cable Sizing Calculation | In this section, you will study calculating size of cables used in substations. |
| Voltage Drop Calculation | This chapter explains the calculation of voltage drop in a substation. |
Who This Substation Design Tutorial is for?
This course on substation design is useful for anyone of the following −
- Electrical engineering students of UG/PG courses
- Working electrical engineers who wants to build career in substation design
- Professionals working in power system projects
Why This Substation Design Tutorial?
This tutorial offers following salient features −
- Step-by-step study of substation design and engineering
- Example substation design drawings and calculation examples
- Substation design guidelines
- Easy and simplified explanation of concepts
FAQs on Substation Design
In this section, we have collected some of the most Frequently Asked Questions (FAQs) on Substation Design followed by their answers.
1. What is the basic design of a substation?
The basic design of an electrical substation is an interconnection of various equipment such as transformer, circuit breakers, isolators, current and potential transformers, protection devices, control system, busbars, and earthing system. This design of substation provides an interconnection between generating stations, transmission system, and distribution system.
2. What are the four types of substations?
The following four are the main types of electrical substations −
- Transmission Substation − This substation is designed for increasing or decreasing the voltages between transmission lines.
- Distribution Substation − This electrical substation is meant for decreasing the voltage levels for power distribution to end consumers.
- Switching Substation − This substation is design for switching the circuit only, and it does not perform voltage transformation.
- Converter Substation − The converter substation is used in HVDC (High-Voltage Direct Current) power system to convert AC into DC and vice-versa.
3. How to build a substation step by step?
The steps involved in building or designing an electrical substation are listed here −
- Step 1 − Selection and survey of site for substation erection
- Step 2 − Study of load and system parameters
- Step 3 − Design and engineering of the substation
- Step 4 − Obtaining necessary permits, approvals, and certifications
- Step 5 − Procurement of equipment
- Step 6 − Construction of foundations and buildings
- Step 7 − Installation of electrical equipment
- Step 8 − Testing and commissioning
- Step 9 − Operation and maintenance
4. What is the size of a substation?
The size of a substation completely depends on its voltage class, for example a small distribution substation can be designed on a 100 to 500 m2 area, while an extra-high voltage substation requires several acres to install.
5. What is an electrical substation design engineer?
An electrical substation design engineer is one who studies, plans, and designs the drawings, layouts, and defines technical specifications of the substation. Substation design engineer ensures the substation must operate safely, efficiently, and complies with regulatory standards.