This thesis is concerned with the optimal scheduling of hydro-thermal power generation systems. This problem, usually referred to as the unit commitment and economic dispatch problem, manifests itself as a large scale mixed integer programming problem. In the first instance a linear model is built and solved using branch-and-bound. This approach is, however, very expensive in terms of computational time. Using Lagrangian relaxation the original primal problem may be written in a dual formulation: the problem then admits decomposition into more tractable subproblems. Furthermore, the primal solution can be approximated closely from the dual solution using the duality gap as a termination criterion. A heuristic is used to construct nearly optimal solutions to the primal problem based on the information provided by the dual problem. The decomposition is such as to allow an implementation on a transputer array with significant reductions in the computational time. An investigation into the application of genetic algorithms to power scheduling shows that this approach is feasible although expensive in terms of computational time. Lagrangian relaxation is next used to solve a nonlinear model incorporating the purchasing and selling of electricity. The information provided by the Lagrange multipliers which can be interpreted as shadow prices, is used to determine the best strategy for the purchasing and selling of energy. Nonconvex programming problems such as this may exhibit a duality gap, that is a difference between the optimal solution of the primal and dual problems. An investigation of this problem for power scheduling linked the existence of this gap to the operating constraints of the system.

The prediction of mass oscillation behaviour is an important part of the hydraulic design of a hydro-electric power scheme containing one or more surge chambers. Currently design practice is to employ computational models. However, the use of hydraulic models in the design of large or complex surge systems provides a useful means of corroborating results from computational studies. This thesis is concerned with the development of techniques for improving the accuracy of both methods. The first part of the thesis deals with the formulation of equations and techniques required for the development of a computer program capable of analysing a wide range of chamber configurations. The majority of these techniques are employed in a computational model, the salient features of which are discussed in some depth. The second section is concerned with the derivation of scaling relationships between prototype schemes and their corresponding hydraulic models. This is supplemented by a discussion of some practical aspects in the design and construction of models. The study culminated in the construction of a hydraulic model of the 1800 MW Dinorwig scheme. Advances in microcomputer technology have enabled them to be used, at reasonably low cost, in customised monitoring/control systems which improve the quality of hydraulic model tests. A number of techniques were developed which were incorporated in a program package for a 32 kilobyte microcomputer for use with the Dinorwig model. Further techniques are discussed in which monitored data is susbjected to further computational analysis. This includes a technique for combining results from hydraulic and computational models to produce a more accurate prediction. These techniques were used in a study of the Dinorwig scheme which revealed that as a result of an amendment to the chamber design, the original specification for the limits of surge amplitude are not satisfied.

In this thesis a mathematical and computer model is formulated to accurately represent the behaviour of the hydraulic and mechanical systems in a hydro power plant. It includes the elastic behaviour of the hydraulic system and the actual operating characteristics of the hydromachines under consideration. After verifying the accuracy of this detailed hydraulic/mechanical model, frequency response tests are conducted to enable a comparison to be made with the IEEE transfer function model. This transfer function although widely used and accepted as a hydro power scheme model in power system and governor studies (1-5) does not represent waterhammer in the hydraulic system or the actual behaviour of the hydromachines. The frequency response tests which are reported in this thesis clearly highlight the severe practical limitations of this model at both low and high frequencies of governor operation. The frequency response results for the detailed hydraulic/mechanical model also enable improved linear transfer functions to be derived. Finally, with the aid of an existing power system stability computer program, the responses of the detailed hyrdaulic/mechanical model, the derived linear transfer function model and the IEEE transfer function model to variations in load are compared in the time domain.

No description available.

A regional assessment of the potential effects of introducing transmission facilities in alternative corridors east of Lake Winnipeg was conducted. The primary focus of the study was on the impact of transmission facilities on outdoor recreation. Several proposed transmission corridors were compared on the basis of the potential negative impact on five factors: existing development providing outdoor recreation facilities, polices and planning objectives east of Lake Winnipeg, natural resources used for outdoor recreation, ecological processes and natural ecosystems and the appearance of the landscape. The West Corridor and W₁ trunk along the east shore of Lake Winnipeg was considered to have the least impact on outdoor recreation, and further study of this alternative was recommended. / 1978

Manitoba Hydro's diversion of the Churchill River at Southern Indian Lake, part of a multi-million dollar hydro-electric development in northern Manitoba, will have extensive economic, social and environmental implications. The impact that the project may have on slush-ice formation in the estuary at the Port of Churchill is one such implication. Previous studies have suggested that reduced flows on the lower Churchill River may alleviate the problem of slush-ice formation which physically terminates the navigation season at Churchill. A reduction in the formation of slush ice would make feasible an average tow week extension of the navigation season. The primary objective of this study was to assess the effect of the Churchill River diversion on the length of the navigation season at the Port of Churchill. A secondary objective was to determine the relationship between the physical variables (slush ice and sedimentation) and the economic variable (insurance coverage) that influence the length of the navigation season. A field trip to Churchill was made in late July, 1973 to collect data. Interviews with hydrologists, ice observers, and National Harbours Board personnel were conducted at this time. In the data analysis, October Churchill River discharges and meteorological data on climatic factors were correlated with dates of Churchill harbour closure due to slush ice for the period 1928-1972......

No description available.

This study examines the effects of 10 years of river regulation on the sediments and sediment transport processes within the gravel-bedded River North Tyne. The North Tyne was regulated following the closure of Kielder dam in 1981. Since 1984, the releases from Kielder reservoir have been dominated by the generation of hydro-electricpower. The work combines a long term review and re-survey of pre-regulation sediment and bathymetric databases, with measurements of contemporary sedimentological and sediment transport processes. This has involved the application of a range of techniques designed to characterise the bed morphology and sediments. These included two new techniques for determining the structure and strength of gravel-bed surfaces. The results of these surveys revealed subtle changes in the grainsize composition of riffle sediments, characterised by an increase in the frequency of coarse particles at the surface, and the accentuation of bed structure and particle compaction. This has resulted from a process of hydraulic winnowing sustained as a result of the high shear stresses experienced on riffles during the passage of the hydropower release wave. Direct measurements of sediment transport using a range of tracing and trapping techniques identified a sediment flux divergence between riffles and pools. During rising discharges, sediments are selectively restrained by bed structure on riffles, whilst pool sediments become competent in the order pool-head, mid-pool, pool-tail. This generates a queuing system for sediments culminating at high discharges in the evacuation of the pool-tail to the downstream riffle. The presence of bed structure on riffles presents a surface of higher particle entrapment probability; the net result of which is lower particle velocities over riffles than in pools, and a subsequent choking of riffles with pool sediments. The interaction of the regulated flood waves and the riffle-pool morphology produces riffle degradation and pool-tail aggradation, although at rates much lower than in a neighbouring regulated river. Hydropower releases retard the rates of aggradational channel change caused by the reduction of flood magnitude. However, historical evidence suggests that catchment sediment supply is variable through time, and should new supplies be accessed, major channel changes should be anticipated, particularly at the tributary junctions. The results of this study have direct implications for the management of game fisheries in regulated rivers, and for understanding the relationships between flood waves and sediment transport in morphologically diverse channels.

Thesis (M.S.)--University of Wisconsin--Madison, 1967. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

The cascaded reservoirs hydropower plant is a complex nonlinear system that involves interacting input and output nonlinear parameters, nonlinear flow rates, and nonlinear dynamical hydraulic heads. This thesis aims to enhance the existing cascaded reservoirs hydropower systems and future ones by new designs of control and optimization systems based on fuzzy logic. In this thesis, a new nonlinear mathematical model of a cascaded reservoirs hydropower plant is developed. The developed model was accurate enough to represent and simulate the plant nonlinear dynamics and to design and test three new fuzzy control systems addressing three major cascaded reservoirs hydropower plant problems. The first one is a fuzzy turbine governor replacing the classical PID controller, the second is a fuzzy controller for three hydraulically coupled turbines under nonlinear and interacting process conditions, and the third is a fuzzy supervisory control and optimization system for geographically-separated systems using the same mass of water in a partially-pumped-storage scheme.