Description and contextualization of the subject

“Introduction to the Electrical Power System” is an optional subject/course that is taught at the beginning of the Master. The aim of the subject is to provide the students with the required power system background.



The students require a previous knowledge of circuit theory, including the alternating current (AC) circuits and the complex representation of voltage and current phasors. They also require a background in electromagnetic theory.



In the Master, this introductory subject is complemented with other two advanced subjects to give a comprehensive description of the power systems. In “Grids operation and control” the voltage and frequency control in the power systems is described. For this aim, some previous knowledge acquired in “Introduction to the Electrical Power System” is required:

• Describe the general topology of the power systems making a clear differentiation between the transmission and the distribution systems.

• Calculate the voltage and current phasors, and the active, reactive and apparent power in delta-connected or star-connected three-phase power systems.

• Represent and calculate the three-phase power system in the per unit system.

• Describe the transformer, the induction machine and the synchronous machine and make calculations of the voltage and current phasors, and active, reactive and apparent power.

• Describe the overhead lines and the underground lines and make calculations of the voltage and current phasors, and active, reactive and apparent power.

In “Disturbances and protections in Smartgrids” the protection against faults in the power system is described. For this aim, some previous knowledge acquired in “Introduction to the Electrical Power System” is required:

• Represent and calculate the three-phase power system in the per unit system.

• Describe the representation of the unbalanced three-phase systems by the symmetrical components and calculate the asymmetrical faults.

• Describe the substation and switchgear of the distribution networks.



The Smartgrids describe the future power network that will make extensive use of modern information and communication technologies to support a flexible, secure and cost-effective de-carbonised electrical power system. Smartgrids are intelligently controlled active networks that facilitate the integration of distributed generation into the power system. “Introduction to Smartgrids” is the introductory course to the Smartgrids. A greater involvement of the load in its operation is required in the Smartgrids. Hence an important aspect of the Smartgrid concept is demand side participation. This is described in “Demand Side management (DSM)”. The Smartgrids are the evolution of the actual power systems. For this reason, the knowledge of the actual power systems is required to understand the Smartgrids. The basic concepts of the power systems are described in “Introduction to the Electrical Power System”.



Some subjects deal with the distributed generation sources: “Dynamic modelling of distributed generation sources”, “Modelling and control of wind turbines”, “Modelling and control of

renewable generation farms and participating to ancillary services”. For this subjects, some previous knowledge acquired in “Introduction to the Electrical Power System” is required:

• Calculate the voltage and current phasors, and the active, reactive and apparent power in delta-connected or star-connected three-phase power systems.

• Describe the transformer, the induction machine and the synchronous machine and make calculations of the voltage and current phasors, and active, reactive and apparent power.



The connection of many renewable generation sources to the grid is made by power converters. The development of the power electronic converters and their control systems is a key aspect to understand the development of the distributed generation and the smartgrids. In the Master, some subjects deal with the control of power converters: “Power converters”, “Modelling and control of storage systems and associated converters”, “Control of the machine-side converter-generator set”, “Component connection to the grid by DC/AC converters. The knowledge of the actual power systems is required to understand the requirements of the power converters. The basic concepts of the power systems are described in “Introduction to the Electrical Power System”.



In the event that the sanitary conditions prevent the realization of a teaching activity and / or face-to-face evaluation, a non-face-to-face modality will be activated of which the students will be informed promptly

Ordinary call: orientations and renunciation

The assessment is based on continuous evaluation. The assessment tools are:

• Assignments (Questions to discuss & Practical tasks): Weight 50 %

• Written examination (Calculation exercises): Weight 50 %



ASSIGNMENTS



An assignment is completed for each task. The assignments are evaluated and feedback is provided.



The “questions to discuss” and the “laboratory exercises” are made in groups of 2 students. The “calculation exercises” are made individually.



Assessment requirements:

• It is obligatory to do in time at least the 90 % of the assignments.

• The minimum mark required in the assignments is 5/10.



If the assessment requirements for the assignements are not fulfilled the mark in the subject is FAIL.





WRITTEN EXAMINATION



The written examination comprises several calculation exercises.



Evaluation criteria:

• The total mark is divided among the magnitudes calculated in the exercises. The weight of each calculated magnitude is defined in the exam.

• The mark of each calculated magnitude is based on the obtained value:

- Incorrect: 0 %

- Correct: 100 %



Assessment conditions:

• The minimum mark required in the exam is 5/10.



If the minimum mark required in the exam is not obtained the mark in the subject is FAIL.

Extraordinary call: orientations and renunciation

The assessment is based on final evaluation. The assessment tools are:

• Written examination 1 (Theoretical concepts & Laboratory): Weight 50 %

• Written examination 2 (Calculation exercises): Weight 50 %



The written examination 1 is not obligatory if the assignments (Questions to discuss & Practical tasks) of the ordinary evaluation are made satisfactorily.



The written examination 2 is similar to the written examination of the ordinary evaluation.

Temary

1. The electrical power system

• Power system basic principles

• Transmission system

• Distribution system

• Distributed generation

• Smart grids



2. Electrical machines

• Synchronous machines

• Asynchronous machines

• Transformers

• Generation systems



3. Power lines

• Overhead lines

• Underground lines

• Line models



4. Unbalanced three-phase systems

• Symmetrical components

• Asymmetrical faults



5. Substations and switchgear in the distribution system

• Switchgear

• Instrumentation transformers

• Primary substation (Distribution substation)

• Secondary substation (Distribution transformer)

Bibliography

Compulsory materials

Documentation of the subject's web page. Accessible at: https://egela.ehu.eus/

Basic bibliography

[1] E. Lakervi, E. J. Holmes, Electricity Distribution Network Design, IET, 2003.

[2] N.Jenkins, J. Ekanayake, G. Strbac, Distributed Generation, IET, 2010.

[3] B. Fox, L. Bryans, D. Flynn, N. Jenkins, D. Milborrow, M. O'Malley, R. Watson, O. Anaya-Lara, Wind Power Integration: Connection and System Operational Aspects, IET, 2014.

[4] J. M. Gers, Distribution System Analysis and Automation, IET, 2013.

[5] S. Stewart, Distribution Switchgear, IET, 2004.

In-depth bibliography

[1] S. N. Vukosavic, Electrical Machines, Springer, 2013.



[2] H. M. Ryan, High-Voltage Engineering and Testing, IET, 2013.



[3] J. M. Gers, E. J. Holmes, Protection of Electricity Distribution Networks, IET, 2011.



[4] M. H. J. Bollen, The Smart Grid: Adapting the Power System to New Challenges, Morgan & Claypool, 2011.



[5] M. E. EI-Hawary, Electrical Power Systems. Design and Analysis, IEEE, 1995.

Links

[1] European Distribution System Operators' Association for Smart Grids, http://www.edsoforsmartgrids.eu



[2] European Network of Transmission System Operators for Electricity, https://www.entsoe.eu



[3] Union of the Electricity Industry – EURELECTRIC, http://www.eurelectric.org/



[4] Red Eléctrica de España – Red21, http://www.ree.es/en/red21



[5] Ormazabal, http://www.ormazabal.com/en



[6] European Technology Platform for SmartGrids, http://www.smartgrids.eu



[7] Iberdrola Distribución Eléctrica, http://www.iberdroladistribucionelectrica.com/webibd/corporativa/iberdrola?IDPAG=ENSOCDISCONNEG