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This reason to carry out this investigation was a complaint from international airport about increased maintenance cost and insufficient reliability of runway lighting systems. The exhaustive investigation of overall lighting installation was carried out, which comprises lighting parameters, mechanical parameters and electrical parameters. The possible causes of luminous flux drop and significantly...
The paper deals with topologies of two, three and four leg converters for two-phase AC motors and the analysis of space vector pulse width modulation. Space Vector Modulated Direct Torque Control (SVM-DTC) for the two-phase induction motor is also used. Proposed control technique and estimators are simulated with Matlab/Simulink. Experimental verification is done with dSPACE environment.
This paper describes auxiliary power supply for supplying high-side MOSFET driver using piezoelectric transformer. The proposed circuit consists of the piezoelectric transformer and driving circuit. The circuit allows 100% duty cycle of the high side MOSFET driver. Used piezoelectric transformer works in radial vibration mode. To verify the power supply function the full bridge convertor was used...
This paper is focused on the usage of the organic Rankine cycles in the current and the new proposed electric power plants. Firstly, the current situation of the usage of these cycles is mentioned. In the next part, the motivation of the utilization, advantages and disadvantages of these cycles are described. Then these cycles are divided by the different working fluids. Further, the modeling of the...
This paper deals with the methodology of software to promote optimised operation of the transmission network. The methodology is based on the real data referring to operating temperatures and the power transmitted over 220 kV and 400 kV lines. This is an input database, formed by the values of power transmitted at a real time temperature. The software designed here offers a choice of the line to be...
The paper discusses the influence of prosumers on power and energy losses in a low-voltage (LV) network. The essential criteria are stated of connecting microgeneration plants to the LV network.
Durability and reliability of cable lines is related to the quality of insulation materials, proper installation and maintenance during operation, as well as its mode of operation and not least by the action of degradation factors during operation. Neglecting any of these factors can significantly shorten the designed life or cause damage during operation. Producers in technical terms normally guarantee...
Absorption current measurements and very low frequency dielectric measurements were performed to evaluate the insulation properties of halogen free fire retardant cables at various temperatures. Changes of electrical parameters have been used for the cables characterization and comparison. The results of measurements proved a complex character of the dielectric phenomena, which consist of several...
The change of operating conditions by circuit breaker switchings or initiation of emergency conditions (short circuits) is accompanied with transient processes. The physical nature of a transient process is redistribution of the stored energy between inductive and capacitive network elements. In some cases, circuit breaker opening may induce high-frequency overvoltages, while circuit breaker closing...
Technical systems which operate in the power industry are the critical systems of strategic importance. In case of such systems the task consisting in the avoidance of the failure occurrence has an extraordinary significance. The failure occurrence is interpreted as the transition of the system technical state from the area of the ability states to the area of the inability states. Therefore, the...
In this paper, the problem of placement and rated power of capacitor banks in the Distribution Network (DN) is considered. We try to suggest the best places for installing capacitor banks and define their reactive power. The considered formulation requires the optimization of the cost of two different objectives. Therefore the use of properly multiobjective heuristic optimization methods is desirable...
This paper investigates the electrical breakdown of biaxially oriented polypropylene (BOPP) film during accelerated DC and thermal ageing. The DC breakdown voltage of 6.5 μm thick capacitor grade polypropylene (PP) films was measured. Two types of films with different crystallinity were tested. 88 breakdowns per sample were collected. The scale and shape parameter of the Weibull distribution were...
Progressive processing method which uses microwave assisted gasification of selected types of waste is discussed in this work. A brief summary of waste management in the EU and processing capabilities are given in the introduction. The next section discusses the legislative aspects of waste management. Substantial part presents the research results achieved when microwave assisted gasification was...
This paper presents the design and simulation of an non isolated DC-DC Cuk converter. The input current control is provided with pulse-width modulation (PWM). A closed control loop is used with two proportional-integral (PI) controllers for the current and voltage. The DC-DC Cuk converter is used with Simulink cells for battery and supercapacitors (SC) to simulate the charging and discharging process...
The subject of this paper is the calculation of the induction machine air gap flux density distribution. Following previous paper, the parameters affecting the distribution are integrated to create the final no-load flux density distribution. The no-load calculations are valid for every type of winding and can be applied to almost every type of electric machine. To calculate the flux density distribution...
The paper presents an innovative concept of the new area measuring algorithm and new area decision algorithm for power lines' distance protection. These algorithms improve the operating conditions of the distance protection. The primary purpose of the new measuring algorithm is correct the short-circuit impedance calculation. The purpose of the new decision algorithm is correct identify of the line...
In this paper, the evaluation of the concept of impedance differential scheme for long transmission line protection is presented. Using the voltages and currents of both line ends, the differential impedance is calculated. Capacitive charging current which constitutes the main drawback of current differential protection is eliminated in presented protection method. What is more, the advantage of presented...
Transmission expansion planning requires static and dynamic analyses. Planning criteria include the selection of contingencies consisting of faults and their clearing, performance standards, transmission system adjustments, and corrective action plan. Performance standards relating to power system dynamics mainly concern the voltage ride through and transient angle stability i.e. retaining synchronism...
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