Master's Thesis

Utilization of Phasor Measurement Units in Electrical Power Grids

Final Thesis 3.63 MB

Author of thesis: Ing. Hamza Omar

Acad. year: 2024/2025

Supervisor: prof. Ing. Petr Toman, Ph.D.

Reviewer: Ing. Obed Muhayimana

Abstract:

This study investigates the use of Phasor Measurement Units (PMUs) to enhance real-time monitoring, control, and state estimation of power grids in modern power systems. From the IEEE 39-bus system simulated using PSCAD, the research establishes an optimized strategic PMU placement scheme for achieving full grid observability. With the implementation of the Particle Swarm Optimization (PSO) algorithm, 13 PMUs are strategically placed to achieve precise voltage and current phasor measurements. The study evaluates the impact of PMU measurements on improving state estimation accuracy and reliability, as validated by PSS/E benchmarks. Findings reflect enhanced grid stability and reliability with a maximum voltage magnitude and phase angle errors of 3.15% and 9.40°, respectively, testifying to PMUs' central role in modern power system management.

Keywords:

Phasor Measurement Units, Power System Monitoring, State Estimation, IEEE 39-bus System, Particle Swarm Optimization, Grid Observability, Real-time Control, Voltage and Current Phasors

Date of defence

10.06.2025

Result of the defence

Defended (thesis was successfully defended)

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Grading

C

Process of defence

The student presented his diploma thesis titled Utilization of Phasor Measurement Units in Electrical Power Grids. The supervisor's evaluation was presented by Prof. Toman, while the opponent's evaluation and related questions were introduced by Mr. Muhayimana. The student was able to answer the opponent’s questions. Dr. Ptáček asked a supplementary question regarding the impact of renewable energy sources on the risk of blackout. Prof. Katovský followed up with a question related to the error analysis in the specific simulation case. With slight assistance, the student managed to answer.

Language of thesis

English

Faculty

Department

Study programme

Electrical Power Engineering (MPA-EEN)

Composition of Committee

prof. Ing. Petr Toman, Ph.D. (předseda)
doc. Ing. Petr Baxant, Ph.D. (místopředseda)
Ing. Branislav Bátora, Ph.D. (člen)
Ing. Michal Krbal, Ph.D. (člen)
Ing. Jiří Ptáček, Ph.D. (člen)
prof. Ing. Karel Katovský, Ph.D. (člen)

Supervisor’s report
prof. Ing. Petr Toman, Ph.D.

The main goal of the diploma thesis was to understand the theory of synchronous phasor measurement and literature review on the use of phasor measurement units. Furthermore, to understand the basics of state estimation theory and the application of phasor measurement units for state estimation.
The student completed the partial tasks and it can be stated that all parts were submitted in an acceptable form and content.
-Page 16-17, section 2.3.1 – last three paragraphs were repeated from content point of view from section 2.3 (page 15).
-Page 20, last sentence is incomplete.
-Reference [8] is not cited in the text.
The assignment was completed. The student worked independently, presented and consulted on partial results. The range of literature used is sufficient, sources are almost properly cited. The formal and graphic level of the work is good.
I recommend the thesis for defense. Points proposed by supervisor: 73

Grade proposed by supervisor: C

Reviewer’s report
Ing. Obed Muhayimana

The thesis dealt with the use of phasor measurement units (PMUs) in electrical power systems. The author focussed on the basical concept of the PMUs, their applications in the power system's real-time control and monitoring as well as their contribution in the systems' state estimation. The IEEE 39-bus test system was considered as a case study and an optimal placement of PMUs was handled.
In section 1, the author introduces the study explaining the study problematic and motivations as well as some historical background of PMUs. But in sub-section 1.3 where the author discusses the role of the current synchrophasor measurements in the grids, the relationship or the link between the listed elements and the rest of the paragraph is not clear. In sub-section 1.5, the author mentioned: '' Here are the key roles and purposes of the voltage measurements in the grid'' but no role and no purpose is provided!
In sub-section 2.3 three successive paragraphs were copied and pasted in the sub-section 2.3.1. Even though the paragraphs are similar, they have the reference [1] in 2.3 and reference [3] in 2.3.1 which is questionable.
In section 2, the study discussed the phasor measurement unit and their applications but for PMU application sub-section, the author just listed different applications with no explanation about them. The details on different PMU applications were necessary since it is one of the recommended points to cover according to the given instructions. Fortunately, some of the applications were discussed in the rest the work and if it were not the case, this point could be considered as uncovered.
In sub-section 3.2, the last sentence on page 20 looks incomplete.
The references are appropriate, enough and well-presented but it is not seen where the reference [8] was cited in the text. In the sub-section 2.3.1 there are many paragraphs without references while it is obvious that the expressed ideas are from other literatures.
The rest of the work is well done, the state estimation is quite well done, the case study is well exploited and the considered PMU optimal placement is well done. The obtained simulation results are good as well.
I evaluate the work with grade C (70 points) and recommend it for defence.

Questions for defence:
1. Why is the measurement synchronizing aspect of PMUs crucial for the power system monitoring and control?
2. Is there any disadvantages in using PMUs in electrical power systems?
3. Explain how the use of PMUs in electrical power networks can impact the integration of distributed energy resources. Points proposed by reviewer: 70

Grade proposed by reviewer: C

Responsibility: Mgr. et Mgr. Hana Odstrčilová