# Modelling and control of renewable generation farms and participating to ancillary services

## General details of the subject

Mode
Face-to-face degree course
Language
English

## Description and contextualization of the subject

First part: Ancillary services (50%)

Theoretical presentation: a general introduction to energy production is proposed as a reminder for the overall energy mix, and the introduction to renewable energies. After a brief review of pros and cons of renewables, their share among the energy mix is looked at, along with the contractual frames. This leads to calculations of yield and load capacity factors of several distributed energy resources. Then, the ecomical aspects of energy production are studied, with the main principles of business modelling such as cost expenditures, marginal and fix costs, within the discounted cash flows method. This part leads to calculation of levelized cost of energy for different cases, enabling to find the optimal mix among different sources. Finally, the participation to ancillary services is looked at, along with definitions and the requirements induced on renewable plants. The theoretical presentation is covered in 4 to 6 hours.

Practical exercises: the principles of power flow calculations are detailed, starting with reminders of Kirchhoff law, and leading to the formulation of static load flow equations. Then, two numerical methods are used to solve the set of (nonlinear, simultaneous) equations: starting with Gauss-Siedel method on simple examples, to look at the limitations, and evolve to Newton-Raphson method. Examples let the student experiment the pros and cons of both methods, that are then applied to two and three buses problem. The set of exercises guide the students to an in-depth understanding of how electric system behave, and how voltage and congestions issues can be solved by grid operators. The practical exercises are covered in 8 to 10 hours.

Dissertation: the students are asked to prepare a 15’ presentation as homework and deliver it in front of the class. The topics are selected among a variety of subjects, some more technical (eg: distributed energy protection issues, frequency and voltage regulation,…), some contractual (eg: autoconsumption, energy communities). For each topic, the students are suggested to detail technical, economical and regulatory issues. The dissertation is covered in 2 hours in class, homework preparation time excluded.

Second part: Case study: Wind Farm (50%)

Theoretical part: the basic concepts of the wind farms are presented: definition and type of Wind farms, Wind Farm design and siting, Wind Farm connection to grid, Wind Farm ancillary services, Wind Farm Requirements for Grid Connection, Some Wind Farms examples, Wind Farm software, Wind Farm models. The theoretical part cover 2 hours.

Practical exercises: expending a wind farm, connecting an offshore Wind Farm, Transmission between Wind Farms. The practical exercises cover 12 hours.

Group project: Study of a new Wind Farm. The group project cover 6 hours

## Teaching staff

NameInstitutionCategoryDoctorTeaching profileAreaE-mail
BRUNET , PASCALÉcole Centrale de NantesOtros
CUREA , OCTAVIANÉcole Superieure des Technologies Industrielles Avancées-ESTIADoctor

## Competencies

NameWeight
Students should have updated knowledge about the advanced working techniques and methodologies related to the field of Smartgrids and distributed generation, particularly from the point of view of their control. 5.0 %
Developing operational and management strategies, including advanced techniques, for the grid-level regulation of Smartgrids. 30.0 %
Evaluating and validating models and drivers of different components of Smartgrids, through simulations and experimental testing, using different computing and prototyping tools. 5.0 %
Assessing and comparing the behaviour of Smartgrids and Microgrids obtained through simulation with different operational and management strategies, and justifying the results obtained. 30.0 %
Applying computing and telecommunications tools as a support for control in Smartgrids and Distributed Generation. 5.0 %
Students should be able to communicate about the projects carried out working in multidisciplinary and multilingual national and international teams of professionals and researchers operating in the field of Smartgrids. 5.0 %
Students should acquire sufficient technical and scientific maturity to participate in collaborative projects with other parties, and to adapt autonomously to the continuous development of knowledge and methodologies in the field of Smartgrids. 10.0 %
Students should be trained to understand and analyse technical documents, standards and scientific articles on the topic of the Master, and to apply them in the creation of work and research related to the field of Smartgrids. 10.0 %

## Study types

TypeFace-to-face hoursNon face-to-face hoursTotal hours
Lecture-based121830
Applied classroom-based groups6915
Applied computer-based groups121830

## Training activities

NameHoursPercentage of classroom teaching
Drawing up reports and presentations4.00 %
Exercises15.040 %
Expositive classes12.0100 %
Presentation of projects1.0100 %
Solving practical cases25.040 %
Systematised study18.00 %

## Assessment systems

NameMinimum weightingMaximum weighting
OTROS0.0 % 25.0 %
Presentations10.0 % 25.0 %
Questions to discuss0.0 % 10.0 %
Written examination0.0 % 25.0 %

## Learning outcomes of the subject

At the end of the subject, the students will be able to:

• Understand the basis of electric power transfer

• Make simple economic calculation to assess the profitability of microgrids

• Gather information and produce a short synthesis

## Ordinary call: orientations and renunciation

CONTINUOUS EVALUATION SYSTEM

The evaluation is of ongoing type. It is why it is compulsory to be present in class.

Notation criteria are given at the beginning of first course, and are as follows:

First part: Ancillary services (5/10)

- Attendance: 1/10

- Practical work in class: 3/10

- Presentation: 1/10

Second part: Case study: Wind Farm (5/10)

- Exercises tutorials: 3/10

- Final project: 2/10

FINAL EVALUATION SYSTEM

According to article 8 of the Regulations, regulating the assessment of students in the official degrees, the students shall have the right to be evaluated by means of the FINAL EVALUATION SYSTEM, independently of the fact that has or has not participated in the CONTINUOUS EVALUATION SYSTEM. In order to do so, students must present the following information written to the teacher in charge of the subject the renunciation of the CONTINUOUS EVALUATION within a period of 9 weeks from the beginning of the term. In this case, the student will be assessed with a single final exam. This final exam will consist on an oral exam related to the skills that the students have to acquire in the subject.

RENUNCIATION

According to article 12 of the Regulations, regulating the assessment of students in the official degrees, in the case of CONTINUOUS EVALUATION, the student may renounce the call for proposals within a period which, as a minimum, will be up to one month before the end of the teaching period of the corresponding subject. This waiver must be submitted in writing to the teacher responsible for the subject. In the case of FINAL EVALUATION, a no presentation to the official examination will result in the automatic waiver of the corresponding call. Renunciation of the call will result in the qualification of not presented.

## Extraordinary call: orientations and renunciation

CONTINUOUS EVALUATION SYSTEM

The students that have not pass the subject in the ordinary call will have to carry out again the activities that they have not passed in this call.

FINAL EVALUATION SYSTEM

The exam of this call will be the same as that of the ordinary call, it is to say an oral exam related to the skills that the students have to acquire in the subject.

RENUNCIATION

A no presentation to the official examination will result in the automatic waiver of the corresponding call. Renunciation of the call will result in the qualification of not presented.

## Temary

Theory:

• Part 1: Economics

1. Reminders of renewable energy development worldwide

a. Global energy trends and key-figures

b. Overall installed energy capacity

c. Pros and cons of renewables

d. Contractual aspects (feed in tariff, merchant scheme, PPA)

2. Challenges for renewable integration

a. New uses

b. Grid code and connection requirements

c. Smart-grid benefits

3. Economic computations

a. Cost breakdown

b. Resource, efficiency, yield and load factor

c. Discounted cash flow method

d. LCOE

4. Smart grid modeling

a. Autoconsumption and autoproduction ratios

b. Curtailment and surplus

c. Optimal mix (minimize LCOE or net present value)

Part 2: Power flow

1. Definition and method

2. Why to use it

3. Theory

a. Node law

c. Buses type (PQ, PV, slack)

d. Gauss Siedel load flow formulation

e. Gauss Siedel solving algorithm

f. New Raphson load flow formulation

g. Newton Raphson solving algorithm

Part 3: Wind Farm

1. Definition and type of Wind farms

2. Wind Farm design and siting

3. Wind Farm connection to grid

4. Wind Farm ancillary services

5. Wind Farm Requirements for Grid Connection

6. Wind Farms examples

7. Wind Farm software

8. Wind Farm models

Exercises and practical works:

• Part 1:

1. Estimate worldwide energy production

2. List Ancillary services

3. Suggest a definition of smartgrids

4. List the new challenges the grid is facing

5. Calculate worldwide capacity factor for each technology family

6. Calculate worldwide full load hours for each technology family

7. Calculate levelized cost of energy for a wind farm

8. Calculate levelized cost of energy for a genset plant

9. Model smartgrid with Enersquid online tool

• Part 2:

1. Express current as a function of voltages and impedance (node law)

3. Write the equation of active and reactive power as a function of voltage angles and magnitudes

4. Per-unit calculations

5. Gauss-Siedel exercise #1

6. Gauss-Siedel exercise #2

7. Gauss-Siedel two buses calculations

8. Newton-Raphson exercise #1

9. Newton-Raphson exercise #2

10. Newton-Raphson two buses calculation

11. Newton-Raphson three buses calculation

• Part 3:

15’ presentation and Q&A

• Part 4:

1. Expending a Wind Farm

2. Connecting an offshore Wind Farm

3. Transmission between Wind Farms

• Part 5:

Group project: Study of a new Wind Farm

## Bibliography

#### Basic bibliography

Jim Lambers. MAT610. Summer Session 2009-10

Transmission Lines, EE740 (spring 2013), egr.univ.edu

Le coût du capital, théories, mesures et pratiques. Franck Bancel.

#### In-depth bibliography

Load Flow. A.J Conejo Univ. Castilla La Mancha

Power Flow Analysis, Mohammed Albadi, http://dx.doi.org/10.5772/intechopen.83374 (CC, by)

Pradeep Yemula, power analysis system, lecture notes

#### Journals

Energy Conversion and Management

Renewable Energy

Energy

Power flow

LCOE

Net present value

http://www.egr.unlv.edu/~eebag/TRANSMISSION%20LINES.pdf

www.enersquid.com

www.irena.com

https://en.wikipedia.org/wiki/Discounted_cash_flow