Book Reference : Pages 131-132 1.To understand how electricity is distributed in the UK via the National Grid 2.To understand how transformers are used.

Slides:



Advertisements
Similar presentations
Direct voltage and current 1. Alternating voltage and current 1 The alternating voltage may make an alternating current flow.
Advertisements

Lesson 10: The National Grid.  MUST understand that electricity is transmitted through the National Grid  SHOULD understand why electricity is transmitted.
Understanding Electrical TransmissionDemonstration A1 A Guide to the National Grid Transmission Model Demonstration A1 How is electricity generated and.
Transformers Noadswood Science, 2011.
Electricity and Magnetism Mr D. Patterson. Outcomes explain why electrical energy is transmitted as AC at very high voltages, and describe and explain.
Facts about Power Distribution uses AC not DC currents power is transmitted by ‘high voltage’ (kilovolt) lines but actual household voltage = 120 or 220.
Transmitting Electricity
Transformers.
Noadswood Science,  To understand how step-up and step-down transformers work Monday, August 10, 2015.
1.Where is electricity generated? 2.How are fossil fuels created? 3.What type of energy is stored in a fossil fuel? 4.What is the purpose of the fossil.
Lunch & Learn Project Presents to you: “The Electric Power Grid” By: Dexter Hypolite Electrical Engineer VIWAPA.
Transformers  A transformer is used to change alternating p.d.s. from a lower to a higher voltage or vice versa. A simple transformer consists of two.
Force, Energy & Communication Lesson 10 & 11 TRANSFORMERS.
GCSE Physics Exam Doctor
1 Introduction to Power Systems Expensive! Influential!Intrusive! Source: Riadh W. Y. Habash, Electromagnetic Fields and Radiation, Marcel Dekker, New.
Electricity and Magnetism 29 Alternating Currents and Power Transmission Chapter 29 Alternating Currents and Power Transmission.
Producing Electric Current
Current There are two types of current…… Direct current (dc) in which the current travels in one direction only Alternating current (ac) in which the.
Generator and Transformer. Moving Conductor If a straight conductor is moved in a path perpendicular to a magnetic field, a current is induced in the.
ELECTROMAGNETIC INDUCTION
Khoo Yihan | Chua Cong Yang | Park Seong Jin.  Electricity is generated in power stations at 11000V to 33000V and then stepped up to V by transformers.
P2b(ii) Generating Electricity You will learn about: How electricity is carried How electricity is made Energy Efficiency
“Transformers – Roberts in disguise”
Topic 12: Electromagnetic induction 12.3: Transmission of electrical power 12.3: Transmission of electrical power.
1.If a magnet is moved into a coil of wire a current is induced in the wire. 2.If the magnet is moved out of the coil the direction of the current is reversed.
Transformer Transformer is used to increase or decrease AC Voltage (potential difference). Transformer is consisted of a soft iron core, a primary coil,
Book Reference : Pages To understand that transformers are all around us in everyday life 2.To understand the significance of A.C. 3.To be able.
Transformers. What? Power stations produce high voltage electricity about 25kV A transformer will ‘step up’ this voltage to about 400kV before the electricity.
Mutual Inductance As in a transformer, changing the current in the primary coil causes an induced voltage in the secondary coil i.e. mutual induction has.
Electrical Engineering
Transformer The working principle of a transformer
Lesson 10: The National Grid.  MUST understand that electricity is transmitted through the National Grid  SHOULD understand why electricity is transmitted.
 V s /V p = N s /N p  I p V p = I s V s  I p /I s = V s /V p = N s /N p  V s = (N s /N p )V p  I s = (N p /N s )I p  P = VI; I = P/V (I.
GCSE Science A Physics 1 Transmission of Electricity Learning Outcomes Understand the need for an electrical distribution system Describe the national.
PHYSICS – Electromagnetic effects (1). LEARNING OBJECTIVES Core Show understanding that a conductor moving across a magnetic field or a changing magnetic.
Science A Physics – P1 Science A Physics – P1 Topic 2b : Transmission of Electricity Topic 2b : Transmission of Electricity.
Electrical Consumption: why is ac important Consider a city such as Newark, DE. Assume that 30,000 citizens wish to dry their hair at the same time; that.
National Grid Example a. 1 metre of the copper wires used in the National Grid has resistance. The distance from the power station in Droitwich to Malvern.
6.2 Transformer and high-voltage transmission
P2: Electrical Circuits. Charging objects A balloon rubbed on a sleeve will gain electrons from the sleeve and become negatively charged. The sleeve becomes.
Power in an AC Circuit No power is consumed by inductance or capacitance. Thus power is a function of the component of the impedance along resistance:
Generating Electricity e the need for the National Grid as an electricity distribution system including power use and responding to changing demand.
TRANSFORMERS  A power station produces an AC pd of ~25 kV  This AC pd is stepped up to ~132 kV so that it can transport through cables without losing.
Electromagnetism Notes-3
Electromagnetism Notes-3
COPY this please!.
& 13 transformers.
Electricity is produced at the power station.
In some power stations, heat is produced by burning rubbish or the methane gas produced by the decomposition of waste in tips. Others use “biofuels”: waste.
When an electric current flows in a metallic conductor, the flow of particles is in one direction only, because the current is carried entirely by electrons.
Electric Power Distribution
Transformers.
When we generate power we ramp up the voltage for transmission (up to V) and then when it arrives at homes we ramp it back down for convenient use.
Generating Electricity 7
The National Grid Mains electricity is produced by ______________.
What are transformers and how do they work?
What do all these have in common? What are they used for?
Generators and Transformers
Topic 12: Electromagnetic induction
Producing Electric Current
Power transmission Energy is lost in transmission lines
Electromagnetic Induction & Transformers
Generators.
Electromagnetic induction
Example Example 1: An electric lamp is rated 110 W, 200 V. When the lamp is operated at its rated power and voltage, calculate a) the current flowing through.
Presentation transcript:

Book Reference : Pages To understand how electricity is distributed in the UK via the National Grid 2.To understand how transformers are used to minimise energy losses due to heat during electricity distribution

The UK network of cables (underground and on pylons), transformers and power stations is known as the National Grid. Power stations produce electricity at 25 kV and at 50Hz

Each power station may well produce in the order of MW of electrical power When high currents flow through wires, there is a heating effect (I 2 R). To achieve a given power distribution, there is a choice of voltage and current (P=VI). To reduce the energy lost due to heating, the electricity is distributed at a higher voltage and lower current

In particular step up transformers are used between the power station and the grid to achieve a transmission voltage of kV

Power Station : 25kV National grid : kV Industry 11-33kV (Three phase) Homes 230V (Single Phase)

Power = Current x Voltage (P=VI) Voltage = Current x Resistance (V=IR) Power lost in the cable due to heating = P = I 2 R If a transmission line has a resistance of 500  and carries 1MW of power at 25kV. Then the current will be 40A and the power loss 0.8MW However at 400kV the current reduces to 2.5A and the energy loss reduces to 3.1kW

A transformer has a primary coil with 120 turns & a secondary with 2400 turns. Calculate the required primary voltage to achieve a secondary voltage of 230V [11.5V] A 230V 60W lamp is connected to the secondary coil. Calculate the current through 1.The secondary coil [0.26A] 2.The Primary coil [5.2A]

Explain why the transmission of electrical power over long distances is more efficient at higher rather than lower voltages A power cable has a resistance of 200  is used to deliver 2.0MW of power at 120kV. Calculate : 1.The current through the cable [16.7A] 2.The power wasted in the cable [56kW]