Real time estimation of power system inertia swegrids-logo

SweGRIDS research area SMARTPOWER
SweGRIDS project code SP10
Project type PhD
Status completed
Researcher Dimitrios Zografors   (webpage)
University KTH (EPE)
Project period 2014-11-03 to 2019-11-01   
Project supervisor Mehrdad Ghandhari   (webpage)
Industrial sponsors Svenska kraftnät


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Project abstract

The scope is to develop a method to estimate the system inertia in real-time based on available system data. Initially a test system will be used to develop the method. Then the developed method will be used to estimate the system inertia based on data from a real system to verify the accuracy of the method. The estimated system inertia can be important and valuable information for system operators to operate and maintain the system reliably.


Summary of work

2015. A literature review has been made. A test system was developed and simulations were done, so as to observe the frequency behavior of the system under different disturbances. Methods proposed in bibliography were tried out and their drawbacks were identified. A new method is proposed, where the change in power due to voltage and frequency dependency of the loads and due to governors and excitation systems can be calculated and is included in the estimation. Currently the method is applied to the test system through simulations and the results are promising.

2016 (1). A conference paper was written and presented in 2016 IEEE PES General Meeting in Boston. This paper considered an offline inertia estimation method. The method was tested in Nordic 32 test system under various disturbances. Furthermore, it was compared to two methods that were presented in past literature.

2016 (2). The test system has been modified to a new version of Nordic 32 test system. This system has 25 additional busses and offers more details for the systems of Norway and Finland than the old version. Several simulations have been implemented so as to have a clear picture of this new system.

2016 (3). A new offline estimation method was proposed, which aims to identify the power change due to load voltage dependency and then estimate inertia. The method was applied on the modified Nordic 32 test system under 20 different scenarios and its advantages and disadvantages were identified. The results were composed in a conference paper, which is submitted to 2017 IEEE PES General Meeting. Furthermore, an abstract version is submitted to 12th IEEE PES PowerTech Conference.

2016 (4). The two aforementioned methods in 1 and 3 were compiled to one, which aims to combine their advantages. This method was also tested under different scenarios. Moreover, the behaviour of the method when there is a lack of certain data was investigated, so as to examine if it can be employed under realistic conditions. The results of this investigation are gathered, in order to compose a journal paper.

2017 (1). A conference paper was presented at 2017 IEEE PES General Meeting in Chicago. The paper presented a disturbance-based inertia estimation method, which simultaneously estimates the power change due to load voltage dependency and the inertia of the system. The method was applied on an extended version of the Nordic 32 under 20 different scenarios and its advantages and disadvantages were identified.

2017 (2). A conference paper was presented at the 19th International Conference on Intelligent System Applications to Power Systems in San Antonio. The paper presented a disturbance-based inertia estimation method, which simultaneously estimates the load power change and the inertia constant, by using particle swarm optimization. The method was applied on an extended version of the Nordic 32 under 20 different scenarios and its advantages and disadvantages were identified.

2017 (3). The method that was presented in (2) was applied under different amount of available data and under different load modellings for the test system, so as to examine its robustness and accuracy in more realistic conditions. The results of this application were gathered and they will comprise a journal paper that will be submitted in the end of 2017/beginning of 2018.

2017 (4). A journal paper was submitted to the Electric Power Systems Journal (Elsevier). The paper presented a disturbance-based inertia estimation method, which simultaneously estimates the total power change and the inertia of the system. The method was applied on an extended version of the Nordic 32 under 20 different scenarios and under different amount of available data.

2017 (5). A conference paper was submitted to 2018 IEEE PES General Meeting in Portland. The paper presented a process that predicts the frequency nadir after a disturbance in the system, by using Neural Networks. The process was applied on 3993 simulations obtained from a 5-bus test system and the results are very promising.

2018 (1). A journal paper with title "Power System Inertia Estimation: Utilization of Frequency and Voltage Response after a Disturbance" has been published in Electric Power Systems Journal (Elsevier).

2018 (2). A conference paper with title "Prediction of Frequency Nadir by Employing a Neural Network Approach" has been presented in ISGT Europe, in Sarajevo.

2018 (3). A study visit has been made for 6 months between April and October at Austin, Texas. The purpose of the visit was a collaboration with ERCOT (Texas' Independent System Operator) and University of Texas at Austin. During this visit, we studied the parameter identification of simplified governor response models. A paper has been written and will be submitted to a journal.


Event log

2017. Attendance of IEEE PES General Meeting 2017, and of the 19th International Conference on Intelligent System Applications to Power Systems.

2018. Research visit to UT Austin and ERCOT at Austin, TX for 6 months, between 23rd of April and 19th of October.


Project reference-group

Katherine Elkington,  Svenska kraftnät
Niklas Modig,  Svenska kraftnät
Daniel Wall,  Vattenfall
Lars Olsson,  Seniorit AB


Publications by this researcher

See alternatively the researcher's full DiVA list of publications, with options for sorting.
Publications in journals and conferences usually will not show until a while after they are published.

Frequency Response Assessment: Parameter Identification of Simplified Governor Response Models Using Historic Event Data
Dimitrios Zografos,   Julia Matevosyan,   Robert Eriksson,   Ross Baldick,   Mehrdad Ghandari.
2020,   Cigre Science & Engineering, vol. 17

Real time frequency response assessment using regression
Dimitrios Zografos,   Mehrdad Ghandari,   R. Eriksson.
2020,   10th IEEE PES Innovative Smart Grid Technologies Europe, ISGT-Europe 2020, 26 October 2020 through 28 October 2020

Power System Inertia Estimation and Frequency Response Assessment
Dimitrios Zografos.
2019,   Thesis (PhD), KTH Royal Institute of Technology, TRITA-EECS-AVL 2019:75

Power system inertia estimation : Utilization of frequency and voltage response after a disturbance
Dimitrios Zografos,   Mehrdad Ghandhari,   R. Eriksson.
2018,   Electric power systems research, vol. 161

Prediction of Frequency Nadir by Employing a Neural Network Approach
Dimitrios Zografos,   Tin Rabuzin,   Mehrdad Ghandhari,   Robert Eriksson.
2018,   2018 IEEE PES Innovative Smart Grid Technologies Conference Europe (ISGT-Europe), 21-25 Oct. 2018, Sarajevo, Bosnia-Herzegovina

Power system inertia estimation by approaching load power change after a disturbance
Dimitrios Zografos,   Mehrdad Ghandhari.
2017,   2017 IEEE Power and Energy Society General Meeting, PESGM 2017

Estimation of power system inertia using particle swarm optimization
Dimitrios Zografos,   Mehrdad Ghandhari,   Kaveh Paridari.
2017,   19th International Conference on Intelligent System Applications to Power Systems, San Antonio, USA, 17-20 Sept. 2017

Estimation of Power System Inertia
Dimitrios Zografos,   Mehrdad Ghandhari.
2016,   2016 IEEE PES General Meeting, Boston, 17-21 July 2016

Publication list last updated from DiVA on 2021-09-18 22:02.


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Last generated: 2021-09-18