Introduction to Electric Power Systems by Prof. Roberto Turri

Introduction to Electric Power Systems

Lecture 1 Introduction to Electric Power Systems An overview of the largest and most complex man made "machine" The Electric Power System: introduction Prof. Roberto Turri - Lecture notes on «Electric Power Systems>>

Definition of Electric Power System

1Technical (f. V) standards (economics, lows ... ) Definition of Electric Power System Electric Power System is the interconnected and regulated set of installations for the production, transmission, distribution and use of electrical energy. These installations are, in turn systems, consisting of components and devices, respectively designed and constructed to fulfill the task of producing, transmitting and using electrical energy in the most reliable and economical possible way.

meshed guid , Madial guid Transmission (HV) Utilization Distribution (MV & LV) Generation HU / DC Masmission 30KV usually 3 phase AC Electric Power System is thus "a system of systems" The Electric Power System: introduction Prof. Roberto Turri - Lecture notes on «Electric Power Systems>>

Characteristics of Electrical Energy

2Definition of Electric Power System Electrical energy is produced by conversion of primary energy sources in electric power generators. Electrical energy is often called a final energy, as it is used by the end-consumers for different purposes. In comparison with other final energies as for example gas, oil or coal, electrical energy is characterized by:

• that it is easy to measure and control
• that it could be used for a variety of purposes
• that it can be converted efficiently from different primary sources
• it can be converted to mechanical or thermal energy with a high efficiency
• that it can be transmitted and distributed with reasonably low losses

However, it is difficult to store electrical energy in an efficient way. Therefore, the production of electric power needs to be controlled at each instant to match the consumption and in order to be transmitted and distributed in a safe, reliable and economical way. The Electric Power System: introduction Prof. Roberto Turri - Lecture notes on «Electric Power Systems>>

Scale of the Electrical Power System

3Definition of Electric Power System The manifest usefulness of this form of energy has prompted to huge investments to develop extensive and complex installations capable of producing, transporting, distributing electricity. This is the Electrical Power System, namely the largest industrial system created by mankind. Interconnected network of UCTE UCIE ... ----- ........... UCTE* in numbers

• 430 millions of users
• 2.500 TWh/year of energy supplied to the users
• 560 GW of installed capacity
• 230.000 km of HV lines
• 5.000.000 km of MV&LV lines 1.500 € is the cost per capita for its realization

* Union for the Coordination of the Transmission of Electricity The Electric Power System: introduction Prof. Roberto Turri - Lecture notes on «Electric Power Systems>>

Composition of a Modern Electrical System

4Definition of Electric Power System Composition of a modern electrical system. Electricity is produced in generation plants and transmitted to consumers through a complex network of components, such as transmission lines, transformers, autotransformers, switches, breakers, etc ..

EHV 380kV/130kV highly meshed HV 130kV/20KV MV T 20kV/380V LV The power network can be subdivided:

1. Transmission system
2. Sub-transmission system weakly weshed
3. Distribution system 132/150 KV L > radial 20 KV

The Electric Power System: introduction Prof. Roberto Turri - Lecture notes on «Electric Power Systems>>

System Generation and Transmission Control

5Definition of Electric Power System In order to be able to meet the demand of the continuously varying load, it will be necessary to maintain a so called "rotating reserve" of active and reactive power properly controlled at all times in order to ensure high levels of reliability and good quality of supply, namely constancy of frequency and voltage.

System Generation Control (Load frequency control) Prime mover Prime mover 4 -- Speed Speed ... Other Generating units ... Excitation & Control Shaft Power Genertator Excitation & Control Shaft Power Genertator Voltage Voltage Electrical Power Electrical Power Transmission control (Reactive Power and Voltage control) The Electric Power System: introduction Prof. Roberto Turri - Lecture notes on «Electric Power Systems>>

Origin and Development of Electric Power Systems

Edison's First Electric Power System

6Origin and development of Electric Power Systems First proper Electric Power System (consisting of a generator, a connecting line, a fuse, a meter, and loads) was built by Thomas Alva Edison, at the Pearl Street station in New York City, in late 1882.

• Direct current system consisting of a dynamo, driven by a steam engine that supplied electricity to about fifty customers within a distance of about a mile. The load, consisting entirely of incandescent lamps, was supplied at 110V through a system of underground cables.
• Soon after similar systems were built and put into operation in most major cities around the world.

The Electric Power System: introduction Prof. Roberto Turri - Lecture notes on «Electric Power Systems>>

First Power Plant in Italy

7Origin and development of Electric Power Systems 0 First Power Plant in Italy (Santa Radegonda - Milan, 1883). The Power plant came into operation to supply a system of street lighting and some city users (including the famous Teatro della Scala). D The Electric Power System: introduction Prof. Roberto Turri - Lecture notes on «Electric Power Systems>>

Transition to Alternating Current

8Origin and development of Electric Power Systems The initial diffusion of direct current systems immediately highlighted the limits of DC electricity supply for distances greater than a few kilometers because of the impossibility of maintaining transmission losses and voltage drops within acceptable level. The problem could be solved with the use of the transformer (developed in 1881 by the Frenchmen L. Gaulard and J.D. Gibbs) and therefore the use of alternating current. Understanding the potentialities of the transformer and AC transmission, G. Westinghouse secured the rights to the AC systems developed in the United States and developed the first single-phase AC electric system. With the development of polyphase electrical systems, alternating current transmission became even more attractive. In 1888, Nikola Tesla's studies led to numerous patents on alternating current motors, generators, transformers and transmission systems. Westinghouse acquired the patents for these inventions, thus laying the foundation for today's alternating current systems. -- X. TESLA Số 555.100 The Electric Power System: introduction Prof. Roberto Turri - Lecture notes on «Electric Power Systems>>

Key Milestones in AC Power Systems

9Origin and development of Electric Power Systems 1886 - Marketing of the first Transformer (Stanley-Westinghouse) .1887 - Asynchronous motor (Tesla) .1889 - First long distance transmission of AC electricity (Willamette Fall-Portland - USA), 14 miles . 1892 - First Italian AC generation and transmission (Tivoli-Roma). Tivoli, the water falls used for the first hydroelectric power plant The Electric Power System: introduction Prof. Roberto Turri - Lecture notes on «Electric Power Systems>>

Modern Electric Power Systems

Interconnected Network of UCTE

10What about modern Electric Power System? Interconnected network of UCTE UCTE HRVATSKA ** "BOHNKI LONADO IGOR . .. .. ITALIA The Electric Power System: introduction Prof. Roberto Turri - Lecture notes on «Electric Power Systems>>

European Electricity Transmission Network Diagram

11European electricity transmission network (One-line diagram) DANMARK - --. - - NEDERLAND - SCHEMA SIMPLIFIE DES INTERCONNEXIONS DES PAYS DE LUCPTE VEREINMACHTES SCHEMA DES VERBUNDNETZES DER UCPTE -LANDEER - EMPLIHED DIAGRAM OF THE INTERCONNECTED NETWORK OF THE UCHTE COUNIRES LUXEMBOURG - 1 BELGIQUE - - GREAT BRITAIN - - -- - DEUTSCHLAND | theque puntospair!) - A O O CESKE REPUBLICA - 8 - - + -1 ÖSTERREICH SCHWEIZ - - SLOVENIJA - HRVATSKA PORTUGAL - ITALIA - .. ...... -- - y JU cmana -- ESPAÑA ........ - HELLAS um SHDIPNIA The Electric Power System: introduction Prof. Roberto Turri - Lecture notes on «Electric Power Systems>>

Main Italian Interconnections

12 --- - - FRANCE MAGYARORSZÁG ROMINA I BULGARIA 31.X1 02European electricity transmission network (One-line diagram): Main Italian interconnections ROMANER DÜRS COSGEN SELLRAIN-SH2 WESTTINGE GRYRAU 2 9 PRADELLA 142 2 + 2 2 DIIPPS WEISSENBACH MOREL FRISUR 2 2 ABOLE TAVANASA LA BATMAZ SCHWEIZ EILS OBERSIELACH ROBBIA GORDUND 122 132 AVISE 123 121 MESE SONDRIO VALPELLINE EDOLO PBERIČEVO ŠOŠTANJ bd 4 BULCIAGO S. FORAND CAGNO CISLAGO PLANCAMUNO CA + + GORLAGO TRAVAGLIATO PIOSSASCO CHIAR ITALIA BOVISIO VERDERIO TAVAZZANO IL. LUNA TUZLA LEYNI CADASO REDIPUGLIA SARAJEVO RONDISSONE LACCHIARELLA LA CASELLA SARICCU LONATE TITOGI SCASTELNUOVO CASANICIUN VIGNOLE PARMA DUGALE LA SPEZIA RUBIERA VENEZIA IN DOLD MOSTAR MAGLIANO CALENZANO LBsMASD OBROVAC GACHO S MARTIGNONE - - - -- DEUTSCHLAND - --------- GREAT BRITAIN - - - BELGIQUE -- -- - LUXEMBOURG - = NEDERLAND DANMARK - - ANDREA 4 P. TOLLE PA CAIANO SERMID CAMIN FUJINA MELINA PIASTRA -- VERBOIS -2-4 CHAMOSON BONA METTLEN 2 ÖSTERREICH 2 ? LENZ SOAZZA UKROGLO SLOVENIJA VENAUS MUS GNANO SIOVERTINE HRVATSKA -- PIANEZZA UGLJEVIN NAVI PADRICIANO ZOR JOWVACA SANDRIGA UDINE PLANAIS SOLARIUI VADO LERINE - - The Electric Power System: introduction Prof. Roberto Turri - Lecture notes on «Electric Power Systems>>

Electrical Energy Exchanges

13 2 ZELLIZILLER KAPRUN -European electricity transmission network: Electrical Energy exchanges Physical electricity exchanges * I" llgo aythims UCFE UCTÉ 1999 N S DK 5119- -------------- 598 IRL GB 100 PL Physical energy flows in GWh 8 0.30 5222 612 3636 2853 1327 40 905 UKR 698 14914 13771 4460 68 65 75 687 2018 CH 5 739 1676+ 476 RO 48 49 3 15770 441 I 172 BH 970 7405 158 .542 BG 589 3513 E P 4453 960 GR 1803 MA * Not to be confused with contractual electricity exchanges The Electric Power System: introduction Prof. Roberto Turri - Lecture notes on «Electric Power Systems>>

Network Transport Capacity Limits

14 443 F 1010053089 17158 6778 D 87 429 5693 CZ 1278 0 4728 8685 K 8978 5881 A H 3145 SH YU 664.0 FYROM 28 AL 445 12 1287 665 1954 6248NETWORK TRANSPORT CAPACITY LIMITS inter-areas Francia + Svizzera 200 220 Austria 5.400 4.800 380 300 Slovenia 4.800 4.600 NETWORK TRANSPORT CAPACITY LIMITS WINTER AND SUMMER SITUATION 1.700+2.000 Francia (Corsica) 300 2.200 500 Grecia 600+350 CAPACITÀ DI TRASPORTO (MW) Situazione invernale: ottobre + aprile Situazione estiva: maggio + settembre (escluso agosto) About 14% of Italian consumption is supplied by imported energy > Imports occur predominantly at night and low load hours The Electric Power System: introduction Prof. Roberto Turri - Lecture notes on «Electric Power Systems>>