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Hydropower plants and power systems: Dynamic processes and control for stable and efficient operation
Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Electricity. (Hydropower)ORCID iD: 0000-0003-1638-0792
2017 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

As the largest global renewable source, hydropower shoulders a large portion of the regulation duty in many power systems. New challenges are emerging from variable renewable energy (VRE) sources, the increasing scale and complexity of hydropower plants (HPPs) and power grid. Stable and efficient operation of HPPs and their interaction with power systems is of great importance.

Theoretical analysis, numerical simulation and on-site measurement are adopted as main study methods in this thesis. Various numerical models of HPPs are established, with different degrees of complexity for different purposes. The majority of the analysis and results are based on eight HPPs in Sweden and China.

Stable operation (frequency stability and rotor angle stability) and efficient operation are two important goals. Regarding the stable operation, various operating conditions are analysed; the response time of primary frequency control (PFC) and the system stability of isolated operation are investigated. A fundamental study on hydraulic-mechanical-electrical coupling mechanisms for small signal stability of HPPs is conducted. A methodology is proposed to quantify the contribution to the damping of low frequency oscillations from hydraulic turbines. The oscillations, with periods ranging from less than one up to hundreds of seconds, are analysed.

Regarding the efficient operation, a description and an initial analysis of wear and tear of turbines are presented; a controller filter is proposed as a solution for wear reduction of turbines and maintaining the frequency quality of power systems; then the study is further extended by proposing a framework that combines technical plant operation with economic indicators, to obtain relative values of regulation burden and performance of PFC.

The results show that the coupling between the hydraulic-mechanical subsystem and the electrical subsystem can be considerable and should be considered with higher attention. Effectiveness and applicability of different numerical models are shown, supplying suggestions for further model optimization. For the influence from power systems on HPPs, the dynamic processes and corresponding control strategies of HPPs under diverse disturbances and requirements from power systems are addressed. For the influence from HPPs on power systems, quantifications of frequency quality and the hydraulic damping are conducted utilising proposed methodologies.

Place, publisher, year, edition, pages
Uppsala: Acta Universitatis Upsaliensis, 2017. , p. 140
Series
Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology, ISSN 1651-6214 ; 1494
National Category
Engineering and Technology
Identifiers
URN: urn:nbn:se:uu:diva-318470ISBN: 978-91-554-9871-9 (print)OAI: oai:DiVA.org:uu-318470DiVA, id: diva2:1084456
Public defence
2017-05-19, Polhemsalen, Ångtröm 10134, Lägerhyddsvägen 1, Ångströmlaboratoriet, Uppsala, 13:15 (English)
Opponent
Supervisors
Available from: 2017-04-28 Created: 2017-03-24 Last updated: 2017-05-05
List of papers
1. A Mathematical Model and Its Application for Hydro Power Units under Different Operating Conditions
Open this publication in new window or tab >>A Mathematical Model and Its Application for Hydro Power Units under Different Operating Conditions
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2015 (English)In: Energies, ISSN 1996-1073, E-ISSN 1996-1073, Vol. 8, no 9, p. 10260-10275Article in journal (Refereed) Published
Abstract [en]

This paper presents a mathematical model of hydro power units, especially the governor system model for different operating conditions, based on the basic version of the software TOPSYS. The mathematical model consists of eight turbine equations, one generator equation, and one governor equation, which are solved for ten unknown variables. The generator and governor equations, which are different under various operating conditions, are presented and discussed in detail. All the essential non-linear factors in the governor system (dead-zone, saturation, rate limiting, and backlash) are also considered. Case studies are conducted based on one Swedish hydro power plant (HPP) and three Chinese plants. The simulation and on-site measurements are compared for start-up, no-load operation, normal operation, and load rejection in different control modes (frequency, opening, and power feedback). The main error in each simulation is also discussed in detail. As a result, the model application is proved trustworthy for simulating different physical quantities of the unit (e.g., guide vane opening, active power, rotation speed, and pressures at volute and draft tube). The model has already been applied effectively in consultant analyses and scientific studies.

National Category
Energy Engineering
Identifiers
urn:nbn:se:uu:diva-262746 (URN)10.3390/en80910260 (DOI)000362553000064 ()
Note

Correction in: Energies 9(6) Article number: 477 DOI: 10.3390/en9060477

Available from: 2015-09-18 Created: 2015-09-18 Last updated: 2017-12-05Bibliographically approved
2. Response time for primary frequency control of hydroelectric generating unit
Open this publication in new window or tab >>Response time for primary frequency control of hydroelectric generating unit
2016 (English)In: International Journal of Electrical Power & Energy Systems, ISSN 0142-0615, E-ISSN 1879-3517, Vol. 74, p. 16-24Article in journal (Refereed) Published
Abstract [en]

For evaluating the power quality in primary frequency control for hydroelectric generating units, the power response time is an indicator which is of main concern to the power grid. The aim of this paper is to build a suitable model for conducting reliable simulation and to investigate the general rules for controlling the power response time. Two huge hydropower plants with surge tank from China and Sweden are applied in the simulation of a step test of primary frequency control, and the result is validated with data from full scale measurements. From the analytical aspect, this paper deduces a time domain solution for guide vane opening response and a response time formula, of which the main variables are governor parameters. Then the factors which cause the time difference, between the power response time and the analytical response time of opening, are investigated from aspects of both regulation and water way system. It is demonstrated that the formula can help to predict the power response and supply a flexible guidance of parameter tuning, especially for a hydropower plant without surge tank.

National Category
Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:uu:diva-259529 (URN)10.1016/j.ijepes.2015.07.003 (DOI)000362309100003 ()
Funder
StandUp
Available from: 2015-08-07 Created: 2015-08-07 Last updated: 2017-12-04Bibliographically approved
3. Frequency Stability of Isolated Hydropower Plant with Surge Tank Under Different Turbine Control Modes
Open this publication in new window or tab >>Frequency Stability of Isolated Hydropower Plant with Surge Tank Under Different Turbine Control Modes
2015 (English)In: Electric power components and systems, ISSN 1532-5008, E-ISSN 1532-5016, Vol. 43, no 15, p. 1707-1716Article in journal (Refereed) Published
Abstract [en]

Currently, the Thoma criterion is often violated to diminish the cross-section of the surge tank; therefore, the surge fluctuation is aggravated and the frequency stability becomes more deteriorative. The focus of this article is on stabilizing the low-frequency oscillation of an isolated hydropower plant caused by surge fluctuation. From a new perspective of hydropower plant operation mode, frequency stability under power control is investigated and compared with frequency control by adopting the Hurwitz criterion and numerical simulation. In a theoretical derivation, the governor equations of frequency control and power control are introduced to the mathematical model. For numerical simulation, a governor model with a control mode switch-over function is built. The frequency oscillations under frequency control, power control, and control mode switch-over are simulated and investigated, respectively, with different governor parameters and operation cases. The result shows that the power control has a better performance on frequency stability at the expense of rapidity compared with the frequency control. Other recommendations regarding worst operation cases and choice of control modes are also developed.

National Category
Other Engineering and Technologies
Identifiers
urn:nbn:se:uu:diva-260774 (URN)10.1080/15325008.2015.1049722 (DOI)000359869100003 ()
Available from: 2015-08-24 Created: 2015-08-24 Last updated: 2017-12-04Bibliographically approved
4. Regulation quality for frequency response of turbine regulating system of isolated hydroelectric power plant with surge tank
Open this publication in new window or tab >>Regulation quality for frequency response of turbine regulating system of isolated hydroelectric power plant with surge tank
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2015 (English)In: International Journal of Electrical Power & Energy Systems, ISSN 0142-0615, E-ISSN 1879-3517, Vol. 73, p. 528-538Article in journal (Refereed) Published
Abstract [en]

Aiming at the isolated hydroelectric power plant (HPP) with surge tank, this paper studies the regulation quality for frequency response of turbine regulating system under load disturbance. Firstly, the complete mathematical model of turbine regulating system is established and a fifth order frequency response under step load disturbance is derived. Then, the method of primary order reduction and secondary order reduction, for this complete fifth order system of frequency response, is proposed based on dominant poles. By this method, the complete fifth order system is solved and the regulation quality for frequency response is studied. The results indicate that the complete fifth order system always has a pair of dominant conjugate complex poles and three non-dominant poles. The primary fourth order equivalent system, which is obtained by primary order reduction, keeps the dominant poles almost unchanged, therefore it can represent and replace the complete fifth order system and it is obviously superior to other fourth order systems. The primary fourth order equivalent system is superimposed by two second-order subsystems, one of them is corresponding to two non-dominant real poles (i.e. head wave) and the other one is corresponding to a pair of dominant conjugate complex poles (i.e. tail wave), respectively. In the fluctuation process of frequency response, head wave decays very fast and works mainly in the beginning period while tail wave decays very slowly, fluctuates periodically and works throughout the period. The secondary order reduction of complete fifth order system can be conducted by using the second order system of tail wave, which is the main body of frequency response, to represent the fluctuation characteristics. The most important dynamic performance index that evaluates the regulation quality, i.e. settling time, is derived from the fluctuation equation of tail wave. The different characteristic parameters of turbine regulating system have different influences on the change rules of head wave, tail wave and settling time.

National Category
Other Engineering and Technologies
Identifiers
urn:nbn:se:uu:diva-260775 (URN)10.1016/j.ijepes.2015.05.043 (DOI)000360771800057 ()
Available from: 2015-08-24 Created: 2015-08-24 Last updated: 2017-12-04Bibliographically approved
5. Time response of the frequency of hydroelectric generator unit with surge tank under isolated operation based on turbine regulating modes
Open this publication in new window or tab >>Time response of the frequency of hydroelectric generator unit with surge tank under isolated operation based on turbine regulating modes
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2015 (English)In: Electric power components and systems, ISSN 1532-5008, E-ISSN 1532-5016, Vol. 43, no 20, p. 2341-2355Article in journal (Refereed) Published
Abstract [en]

Aiming at studying the regulation quality of isolated turbine regulating systems under load disturbance and different regulation modes, the complete mathematical model of a turbine regulating system under three regulation modes is established. Then, based on dominant poles and null points, the method of order reduction for a high-order system of time response of the frequency is proposed. By this method, the complete high-order systems are solved and the regulation quality for time response of the frequency is studied. The results indicate that (1) the tail wave, which is the main body of time response of the frequency and the principal factor that determines the regulation quality, is mainly determined by the dominant poles; (2) for the three regulation modes, by deleting the high-order terms, the three equivalent overall transfer functions are fourth order, third order, and third order, respectively, and can be solved; (3) the analytical fluctuation equations of time response of the frequency solved from low-order equivalent overall transfer functions accurately simulate the fluctuation characteristics of time response; and (4) based on damped vibrations decomposed from analytical fluctuation equations, the regulation qualities of three regulation modes are analyzed.

Keywords
hydroelectric generator unit; surge tank; isolated operation; turbine regulating system; time response of the frequency; regulation quality; regulating mode; dominant pole
National Category
Engineering and Technology
Identifiers
urn:nbn:se:uu:diva-265426 (URN)10.1080/15325008.2015.1082681 (DOI)000364312000009 ()
Available from: 2015-10-28 Created: 2015-10-28 Last updated: 2017-12-01
6. Instability analysis of pumped-storage stations under no-load conditions using a parameter-varying model
Open this publication in new window or tab >>Instability analysis of pumped-storage stations under no-load conditions using a parameter-varying model
2016 (English)In: Renewable energy, ISSN 0960-1481, E-ISSN 1879-0682, Vol. 90, p. 420-429Article in journal (Refereed) Published
Abstract [en]

The S-shaped characteristics of a pump turbine make its rotational speed unstable when it starts up under no-load conditions with low head, affecting its ability to connect to the grid. Although advanced strategies for controlling the speed governor can alleviate this problem, they cannot fundamentally resolve the internal mechanisms that cause difficulties with a grid connection. Therefore, this study set out to theoretically explore the root cause of the instability and the dominant factors influencing it. A correlation fitting process was used to simplify the transcendental function for the pipe flow in elastic mode into a high-precision and low-order linear equation. Next, a detailed study of the two key factors affecting system stability (pump turbine S-shaped characteristics and water elasticity) was carried out based on the system model, and a comprehensive parameter that reflects the no-load characteristics was extracted. Furthermore, the Laplace transform and inverse transform decomposition were used to obtain a mathematical expression for the no-load oscillation in order to analyze the oscillation characteristics. Finally, simulations of no-load oscillations under various heads were performed to further validate the accuracy of the extracted comprehensive parameter for the no-load stability.

Keywords
Pumped-storage station, Pump turbine, No-load instability, Water elasticity, S-shaped characteristics
National Category
Energy Engineering
Identifiers
urn:nbn:se:uu:diva-280219 (URN)10.1016/j.renene.2016.01.024 (DOI)000370102400038 ()
Available from: 2016-03-10 Created: 2016-03-09 Last updated: 2017-11-30
7. Extreme water-hammer pressure during one-after-another load shedding in pumped-storage stations
Open this publication in new window or tab >>Extreme water-hammer pressure during one-after-another load shedding in pumped-storage stations
2016 (English)In: Renewable energy, ISSN 0960-1481, E-ISSN 1879-0682, Vol. 99, p. 35-44Article in journal (Refereed) Published
Abstract [en]

The intermittent and unpredictable wind and solar power leads to the frequent transient processing of pumped-storage stations, increasing the probability of load shedding. When one turbine sheds its load, the other turbines in the same hydraulic unit become overloaded and may shed their loads, which is referred to as a "one-after-another (OAA)" load-shedding process. An extremely high water-hammer pressure (WHP), namely, high spiral case pressure (SCP) or low draft tube pressure (DTP), may arise in this case, directly threatening the safety of the PSS. The objective of this study was to theoretically determine the hydraulic connections between the turbines and reveal the mechanism of the rapid rise in the WHP under the OAA load-shedding conditions. Theoretical derivations inferred that the drastic pressure changes in a trail shedding turbine (TST) are caused by the hydraulic connection with the lead shedding turbine (LST) in the S region. Furthermore, numerical simulations and model experiments were performed for the OAA load-shedding process, which confirmed the validity of the theoretical analysis. Finally, an analysis was conducted on the distribution of the water inertia in the upstream and downstream branch pipes, and engineering measures were proposed to guarantee the safe operation of PSS systems.

Keywords
Pumped-storage station, Pump-turbine, OAA load shedding, Transient pressure, Hydraulic connection, Model test
National Category
Environmental Engineering
Identifiers
urn:nbn:se:uu:diva-305290 (URN)10.1016/j.renene.2016.06.030 (DOI)000383811000004 ()
Available from: 2016-10-18 Created: 2016-10-14 Last updated: 2017-11-29
8. Simulation of Wind Speed in the Ventilation Tunnel for Surge Tanks in Transient Processes
Open this publication in new window or tab >>Simulation of Wind Speed in the Ventilation Tunnel for Surge Tanks in Transient Processes
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2016 (English)In: Energies, ISSN 1996-1073, E-ISSN 1996-1073, Vol. 9, no 2, article id UNSP 95Article in journal (Refereed) Published
Abstract [en]

Hydroelectric power plants' open-type surge tanks may be built in mountains subject to the provision of atmospheric air. Hence, a ventilation tunnel is indispensable. The air flow in the ventilation tunnel is associated with the fluctuation of water-level in the surge tank. There is a great relationship between the wind speed and the safe use and project investment of ventilation tunnels. To obtain the wind speed in a ventilation tunnel for a surge tank during transient processes, this article adopts the one-dimensional numerical simulation method and establishes a mathematical model of a wind speed by assuming the boundary conditions of air discharge for a surge tank. Thereafter, the simulation of wind speed in a ventilation tunnel, for the case of a surge tank during transient processes, is successfully realized. Finally, the effective mechanism of water-level fluctuation in a surge tank and the shape of the ventilation tunnel (including length, sectional area and dip angle) for the wind speed distribution and the change process are discovered. On the basis of comparison between the simulation results of 1D and 3D computational fluid dynamics (CFD), the results indicate that the one-dimensional simulation method as proposed in this article can be used to accurately simulate the wind speed in the ventilation tunnel of a surge tank during transient processes. The wind speed fluctuations can be superimposed by using the low frequency mass wave (i.e., fundamental wave) and the high frequency elastic wave (i.e., harmonic wave). The water-level fluctuation in a surge tank and the sectional area of the ventilation tunnel mainly affect the amplitude of fundamental and harmonic waves. The period of a fundamental wave can be determined from the water-level fluctuations. The length of the ventilation tunnel has an effect on the period and amplitude of harmonic waves, whereas the dip angle influences the amplitude of harmonic waves.

Keywords
hydroelectric power plants, surge tank, ventilation tunnel, transient process, wind speed, numerical simulation, wave superposition
National Category
Ocean and River Engineering
Identifiers
urn:nbn:se:uu:diva-283792 (URN)10.3390/en9020095 (DOI)000371831900020 ()
Available from: 2016-04-14 Created: 2016-04-14 Last updated: 2017-11-30Bibliographically approved
9. Eigen-analysis of hydraulic-mechanical-electrical coupling mechanism for small signal stability of hydropower plant
Open this publication in new window or tab >>Eigen-analysis of hydraulic-mechanical-electrical coupling mechanism for small signal stability of hydropower plant
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(English)In: Renewable energy, ISSN 0960-1481, E-ISSN 1879-0682Article in journal (Refereed) Submitted
National Category
Engineering and Technology
Identifiers
urn:nbn:se:uu:diva-318427 (URN)
Available from: 2017-03-24 Created: 2017-03-24 Last updated: 2017-11-29
10. Hydraulic damping on rotor angle oscillations: quantification using a numerical hydropower plant model
Open this publication in new window or tab >>Hydraulic damping on rotor angle oscillations: quantification using a numerical hydropower plant model
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(English)In: IEEE transactions on energy conversion, ISSN 0885-8969, E-ISSN 1558-0059Article in journal (Refereed) Submitted
National Category
Engineering and Technology
Identifiers
urn:nbn:se:uu:diva-318440 (URN)
Available from: 2017-03-24 Created: 2017-03-24 Last updated: 2017-11-29
11. Wear and tear on hydro power turbines: influence from primary frequency control
Open this publication in new window or tab >>Wear and tear on hydro power turbines: influence from primary frequency control
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2016 (English)In: Renewable energy, ISSN 0960-1481, E-ISSN 1879-0682, Vol. 87, p. 88-95Article in journal (Refereed) Published
Abstract [en]

Nowadays the importance and need of primary frequency control of hydro power units are significantly increasing, because of the greater proportion of intermittent renewable energy sources and more complex structure of power systems. It brings a problem of increasing wear and tear of turbines. This paper studies this problem by applying numerical simulation and concise theoretical derivation, from the point view of regulation and control. Governor models under opening and power feedback mode are built and validated by measurement data. The core index, guide vane movement, is analyzed based on ideal sinusoidal frequency input and real frequency records. The results show the influences on wear and tear of different factors, e.g. governor parameters, power feedback mode and nonlinear governor factors.

National Category
Ocean and River Engineering
Identifiers
urn:nbn:se:uu:diva-262747 (URN)10.1016/j.renene.2015.10.009 (DOI)000367759500008 ()
Available from: 2015-09-18 Created: 2015-09-18 Last updated: 2017-12-04Bibliographically approved
12. Wear reduction for hydro power turbines considering frequency quality of power systems: a study on controller filters
Open this publication in new window or tab >>Wear reduction for hydro power turbines considering frequency quality of power systems: a study on controller filters
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2017 (English)In: IEEE Transactions on Power Systems, ISSN 0885-8950, E-ISSN 1558-0679, Vol. 32, no 2, p. 1191-1201Article in journal (Refereed) Published
Abstract [en]

Nowadays, the wear and tear of hydropower turbines is increasing, due to more regulation movements caused by the increasing integration of intermittent renewable energy sources. In this paper, a controller filter is proposed as a solution to the tradeoff between reducing the wear of turbines and maintaining the regulation performance and thereby the frequency quality of the power systems. The widely used dead zone is compared with a floating dead zone and a linear filter, by time-domain simulation and frequency-domain analysis. Simulink models are built and compared with onsite measurement. Then, the time-domain simulation is used to investigate the guide vane movement, the load disturbance and the power system frequency, based on a one-day grid frequency datameasured in this study. In the theoretical analysis, the describing functions method and the Nyquist criterion are adopted to examine the stability of the system with different filters. The results show that the floating dead zone, especially the one after the controller, has a better performance than the dead zone on both the wear reduction and frequency quality. The linear filter has a relatively weak impact on both guide vane movements and the frequency quality. Other related conclusion and understandings are also obtained.

National Category
Ocean and River Engineering
Identifiers
urn:nbn:se:uu:diva-262748 (URN)10.1109/TPWRS.2016.2590504 (DOI)000395865900033 ()
Available from: 2015-09-18 Created: 2015-09-18 Last updated: 2017-04-27Bibliographically approved
13. Analysis on regulation strategies for extending service life of hydropower turbines
Open this publication in new window or tab >>Analysis on regulation strategies for extending service life of hydropower turbines
2016 (English)Conference paper, Published paper (Refereed)
Abstract [en]

Since a few years, there has been a tendency that hydropower turbines experience fatigue to a greater extent, due to increasingly more regulation movements of governor actuators. The aim of this paper is to extend the service life of hydropower turbines, by reasonably decreasing the guide vane (GV) movements with appropriate regulation strategies, e.g. settings of PI (proportional-integral) governor parameters and controller filters. The accumulated distance and number of GV movements are the two main indicators of this study. The core method is to simulate the long-term GV opening of Francis turbines with MATLAB/Simulink, based on a sequence of one-month measurements of the Nordic grid frequency. Basic theoretical formulas are also discussed and compared to the simulation results, showing reasonable correspondence. Firstly, a model of a turbine governor is discussed and verified, based on on-site measurements of a Swedish hydropower plant. Then, the influence of governor parameters is discussed. Effects of different settings of controller filters (e.g. dead zone, floating dead zone and linear filter) are also examined. Moreover, a change in GV movement might affect the quality of the frequency control. This is also monitored via frequency deviation characteristics, determined by elementary simulations of the Nordic power system. The results show how the regulation settings affect the GV movements and frequency quality, supplying suggestions for optimizing the hydropower turbine operation for decreasing the wear and tear.

Series
IOP Conference Series: Earth and Environmental Science, ISSN 1755-1307, E-ISSN 1755-1315 ; 49
National Category
Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:uu:diva-310651 (URN)10.1088/1755-1315/49/5/052013 (DOI)000400156200054 ()
Conference
28th IAHR symposium on Hydraulic Machinery and Systems (IAHR2016)
Available from: 2016-12-17 Created: 2016-12-17 Last updated: 2018-04-04Bibliographically approved
14. Burden on hydropower units for balancing renewable power systems
Open this publication in new window or tab >>Burden on hydropower units for balancing renewable power systems
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(English)Article in journal (Refereed) Submitted
National Category
Engineering and Technology
Identifiers
urn:nbn:se:uu:diva-318444 (URN)
Available from: 2017-03-24 Created: 2017-03-24 Last updated: 2017-03-24
15. Allocation of Frequency Control Reserves and its Impact on Wear and Tear on a Hydropower Fleet
Open this publication in new window or tab >>Allocation of Frequency Control Reserves and its Impact on Wear and Tear on a Hydropower Fleet
2018 (English)In: IEEE Transactions on Power Systems, ISSN 0885-8950, E-ISSN 1558-0679, Vol. 33, no 1, p. 430-439Article in journal (Refereed) Published
Abstract [en]

Power systems are making a transition from purely technical, centrally planned systems to market based, decentralized systems. The need for balancing power and frequency control reserves are increasing, partially due to variable renewable production, which gives an opportunity for new incomes but also a challenge in terms of changed modes of operation with risk for reduced lifetime for controllable power plants. This paper investigates how the allocation of a sold volume of frequency control reserves within a large hydropower production fleet can affect the costs of providing primary and secondary reserves, in terms of its impact on wear and fatigue, production losses, and the quality of the delivered frequency control. The results show that for primary control, low static gain in the governors results in poor quality and a large amount of load cycles of the units. High static gain, on the other hand, increases the production losses. The control work of the fleet can be reduced by using a proper balance of primary and secondary control gain on each unit, although the intuitive results from linear models exaggerate this effect. Automatic secondary control improves the system frequency quality but also increases the wear.

Keywords
hydropower, frequency control, primary control, reserve allocation, wear and tear
National Category
Electrical Engineering, Electronic Engineering, Information Engineering
Research subject
Engineering Science with specialization in Science of Electricity
Identifiers
urn:nbn:se:uu:diva-308437 (URN)10.1109/TPWRS.2017.2702280 (DOI)000418776400038 ()
Note

Title of this article in dissertation reference lists: Allocation of Frequency Control Reserves and its Impact on Wear on a Hydropower Fleet

Available from: 2016-11-25 Created: 2016-11-25 Last updated: 2018-02-07Bibliographically approved
16. Linear Synthetic Inertia for Improved Frequency Quality and Reduced Hydropower Wear and Tear
Open this publication in new window or tab >>Linear Synthetic Inertia for Improved Frequency Quality and Reduced Hydropower Wear and Tear
(English)In: IEEE Transactions on Sustainable Energy, ISSN 1949-3029, E-ISSN 1949-3037Article in journal (Refereed) Submitted
Keywords
frequency control, hydropower, inertia, synthetic inertia, damping, power system stability, wear and tear
National Category
Engineering and Technology Electrical Engineering, Electronic Engineering, Information Engineering
Research subject
Engineering Science with specialization in Science of Electricity
Identifiers
urn:nbn:se:uu:diva-308440 (URN)
Available from: 2016-11-25 Created: 2016-11-25 Last updated: 2017-11-29

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