Sudden pipe bursts occur in high-pressure water transmission pipelines and water distribution networks. The consequences of these bursts can be very expensive due to the outage time while the burst pipe is repaired, the cost of repair, and damage to surrounding property and infrastructure. As a result, it is advantageous to minimise the detection and location time after the burst occurs.Currently, there is no effective solution for the burst detection and location problem in water distribution systems. The applications in oil and gas pipelines and pipe networks show the advantages of continuous monitoring. A number of techniques are used to determine the location and size of a burst. One of the most promising approaches is fluid transient modelling and analysis. Pressure transient analysis has also been successfully applied for detection and location of existing leaks.A sudden pipe burst creates a negative pressure wave that travels in both directions away from the burst point. The analysis of this wave is the main principle for the techniques presented in this thesis. Experiences from previous research suggest that, to achieve the best performance, single pipelines and pipe networks have to be treated separately. Thus, two different approaches for burst detection and location are presented.When a burst occurs in a pipeline, the burst-induced pressure wave travels in both directions along the pipeline and is reflected at the boundaries. Using a pressure trace measured at one location along the pipeline, the timing of the initial and reflected burst-induced waves determines the location of the burst. The presented continuous monitoring technique uses the modified two-sided cumulative sum (CUSUM) algorithm to detect abrupt changes in the pressure iii data caused by the pipe break. The results from both laboratory and field pipelines are used to verify the proposed method. Different burst and measurement locations are tested. The results are promising for burst detection and location in real systems.In the network case, continuous pressure measurements at two locations are analysed. The burst detection and location algorithm is based on the difference between the arrival times of the burst-induced pressure wave at each measurement point and on the measured wave magnitude. The arrival times are determined automatically in real time. A method for determining optimal measurement locations is also presented. Results from numerical simulations show that the proposed technique has potential as a tool for effective detection and location of bursts in real pipe networks.

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The contemporary state of the modelling of the pump station’s electric drive in a complex with its centrifugal hydraulic load has been analysed. It was found that most studies focus either on the modelling and development of automatic control systems for the asynchronous electric drive of pumps or on the optimization of performance indicators of the station as a whole. Besides, usually only one of the subsystems of a pumping station (or an electrically-operated pump unit) is modelled with a good degree of detail: either electromagnetic or hydraulic. This approach does not allow a concurrent research of electromagnetic and hydraulic processes in them. The paper proposes a comprehensive mathematical model of the dynamic modes of the synchronous electrically-operated centrifugal pump unit with a pipeline, in which the electromagnetic and hydraulic subsystems are presented with a balanced degree of detail. The developed model was verified and its viable applications were suggested.

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Purpose. Development of technical and algorithmic solutions for complex improvement of electrotechnologic effectiveness indices of "power supply mains-pumping station" ("SM-PS") complex, improvement of its energy efficiency, obtaining its rational structure and operation algorithm of the system of automatic control of modes of pumping over. methodology. Circuit design and algorithmic solutions were developed on the basis of liquid pumping efficiency indices analysis for various power supply schemes, power circuits connection diagrams and control methods of centrifugal pumping units, which were acquired using mathematical experiments on the developed digital model of "SM-PS" complex. findings. Power supply circuit and centrifugal pump unit connection diagram were developed. A structure and an algorithm for microprocessor system of automatic discrete-continuous control of liquid pumping modes with constant pressure in the pipeline on the full range of the "SM-PS" performance variation were created. Originality. A mathematical model of synthesis of discrete-continuous control of liquid pumping modes using centrifugal pumping units in the structure of the closed-loop system of the pipeline pressure stabilization was developed. Practical value. The use of the developed scheme, schematic and algorithmic solutions makes it possible to improve the electrotechnologic efficiency indices of "SM-PM" complex, in particular, to decrease specific cost of active electric energy, to improve the power factor, to decrease circuit voltage deviation as well as to reduce consumption of total and reactive powers, which results in substantial energy saving. The suggested solutions can be applied while designing new and operating working "SM-PS" complexes.