Lunch & Learn Project Presents to you:

“The Electric Power Grid”

By: Dexter Hypolite Electrical Engineer VIWAPA

Introduction • The electric power grid is an interconnecting

network that supplies electricity to our homes, schools and industry.

• Electricity is used for light, heating, cooling, entertainment and even studying.

• The interconnecting network consist of generating stations that produce electrical power, high-voltage transmission lines that carry power from distant sources, and distribution lines that connect individual customers

Electric Grid Network

Generation

❖ Power plants is where electrical power begins

❖ Typical power plants contain steam generators or gas fired generator.

❖ Wind and Solar farms are also Power Stations

Typical Generation Demand Curve

❖ There are three types ofcurves to classify generationand loads.

❖ Integrating Megawatts (MW) yields Megawatts hours (MWh).

❖ Energy Usage is MWh.

Generation Demand Curve

❖ Consider the function :

❖ What type power station could this be?

❖ What is the maximum power that is generated (MW) and at what time?

❖ How much MWh is produced each day?

AC Power

❖ The power generated at these power stations stations are three phase AC power.

❖ Let’s understand this by taking a look at single phase AC power.

In North America and the Virgin Islands period or frequency is 60 Hz or 16.6667ms.

Three Phase AC Power

❖ In 3-Phase Power, there are 3wires plus a neutral wire.

❖ Each live wire will be offsetfrom each other by 120 degrees.

❖ You can single build a singlephase circuit from a threephase system.

Transmission

❖ Transmission Lines are used to transfer large bulk power over long distances.

❖ There voltages are much higher than generation.

❖ At a generating plant, electric power is “stepped up” to several thousand volts by a transformer and delivered to the transmission line. At numerous substations on the transmission system, transformers step down the power to a lower voltage and deliver it to distribution lines

Distribution

❖ Distribution lines carry power to farms, homes and businesses.

❖ Once the power lines have reached the city, the first step in the distribution grid is to connect to the high voltage lines, and step-down to a lower voltage for distribution

Putting all together on paper

Electric Grid One Line Diagram