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Model of Three-phase Power Microgrid
Macík, Tomáš ; Cipín, Radoslav (referee) ; Pazdera, Ivo (advisor)
The Diploma thesis deals with control of three-phase active rectifier and a three-phase DC/AC converter. It also explains phase-locked loop principle. The theoretical part including first three chapters lists several control approaches to three phase active rectifier and three phase DC/AC converter. Described control approaches to the active rectifier are control in dq frame and control in dq UVW frame. Listed control approaches to the DC/AC converter include cascaded control structure and a full state feedback control. The practical part is divided into last three chapters and includes mathematical description of phase-locked loop principle, model of active rectifier controlled in dq frame and a model of DC/AC converter controlled both by a cascaded control and a full¬ state feedback. The models are created in Matlab Simulink.
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Conductive model of human tissue for electroporation purposes
Zelinková, Kateřina - Šarlota ; Cipín, Radoslav (referee) ; Novotná, Veronika (advisor)
This thesis solves the issue of the distribution of the high voltage pulse at the electroporation of the arget ablation zone. For futher examination of influence electroporation was necessary to first understand theoretically electrical charakter of cells and replace with basics eletrical circumferential elements (RLC). Based on this knowledge, theoretical prerequisites for experimental measurements were derived. Theoretical assumptions were then verified by experimental measurements. In the measurement, the assumptions found were confirmed, but significant performance losses were identified. A new catheter was designed to reduce the loss. Because the production of a new catheter is not economically disadvantageous, the properties of the new catheter were first tested using the simulation cloud environment SIMSCALE, where the heating of the heart tissue after the application of the electroporation pulse was monitored. Furthermore, the electroporation process was simulated in the FEMM program, where emphasis was placed on the propagation of cardiac tissue tension.
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Analysis of concentrated windings of PMSM
Menoušek, Lukáš ; Cipín, Radoslav (referee) ; Vítek, Ondřej (advisor)
This thesis deals with the design, principles of permanent magnet synchronous machines and an analysis of their properties. As part of the work is done familiarization with the materials of permanent magnets and their arrangement, as well as construction of the engine where they are discussed types of winding machine configuration, types of motors with permanent magnets and the list of implemented solutions. In the next part of this work is performed analytical calculation of the two types of engines, with concentrated winding, created models based on calculations in FEMM focusing on the creation of spatial harmonics. Further the model in RMxprt and data from the simulations were compared with analytical computation. Finally the model was created in Maxwell and compared with the analytical results of calculation and simulation in RMxprt program. For this model was created analysis of losses in permanent magnets.
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Modern Mathematical Methods of the Analysis and Synthesis of AC Machines
Cipín, Radoslav ; Skala,, Bohumil (referee) ; Richter, Aleš (referee) ; Patočka, Miroslav (advisor)
The doctoral thesis is divided into three main parts with a focus on induction motors. The first part deals with the electromagnetic design and analysis of windings of AC ma-chines. There is introduced the density of conductors, which describes the distribution of the windings in the slots. There is derived general formula for calculation of the total winding factor applicable to any type of winding. The second part of this work deals with the acceleration method of the induction motors torque-speed characteristics measurement. The measured characteristics are used for exact identification of the equivalent circuit parameters of induction motor. The third section is focused on a very precise identification of the equivalent circuit parameters of induction motor in the form of -circuit. The identification is based on mutual comparison of measured and calculated torque-speed and current-speed characteristics.
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Optimization of magnetic circuit of induction motor for frequency up to 210 Hz
Binek, Martin ; Cipín, Radoslav (referee) ; Vítek, Ondřej (advisor)
This master’s thesis first deals with the theory concerning induction motor. It briefly desbribes the construction of three-phase induction motors, the generation of tractive force, power flow with loss distribution and also torque characteristic. In the next part an analytical calculation of the parameters of equivalent circuit for an existing induction motor with known dimensions is performed. After the calculation it is possible to find out the rated parameters of the motor, which makes it possible to further compare results with the values obtained by other methods. The next step was to create a model of the motor in RMxprt program, which is later also translated to ANSYS Maxwell 2D model. Simulations were carried out in both interfaces. As the next step the results obtained by the three methods are compared with measured values and also evaluated. The final part of the thesis focuses on the optimization of the magnetic circuit for higher frequencies. Efficiency of the modified induction motor is examined for higher frequencies using RMxprt Optimetrics and this procedure is performed for both default and alternative electrical steel materials.
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Measurement of the losses in ferromagnetic materials
Schnabl, Jan ; Cipín, Radoslav (referee) ; Patočka, Miroslav (advisor)
The first part of this thesis deals with the basic division of magnetic circuits and materials which are used for their construction. The next section focuses on the description of losses in the magnetic circuit. There is a description of hysteresis losses and eddy losses. The chapter contains the theoretical basis for the mathematical description of hysteresis and eddy losses. There is an analysis of the losses caused by the first harmonious and additional losses caused by harmonics. The third part describes the measurement of losses in ferromagnetic materials. There are all methods that are used. The fourth and fifth chapter is devoted to practical measurement hysteresis losses 1. phase transformer and measuring eddy losses in the inductor using the pulse method.
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Step down convertor
Koutný, Martin ; Kadlec, Josef (referee) ; Cipín, Radoslav (advisor)
Thesis deals with the evaluation of the solutions and the design of the DC voltage converters. The first describes the different types of converters, which subsequently choose types of resources for the construction. In other chapters of the work devoted to the design of schemes, selected types of sources and selection of circuits and components therefor, for the manufacture, including calculations cooling performance parts. The last chapter is devoted to the description of the structure and measurement of the produced sources. The measurements are primarily deals with the verification of the specified parameters.
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Analysis of core loss of a small induction machine
Plíšek, Oldřich ; Cipín, Radoslav (referee) ; Mach, Martin (advisor)
The aim of this master´s thesis is to analyze core losses of a small induction motor. Analyzed values are obtained from laboratory measurements, software analysis and 2D finite element method simulation. The theoretical part of this thesis consists of two parts. The analysis of the higher spatial harmonics presents in the induction motor and the analysis of core losses of the motor. Practical part consists of laboratory measurements according to ČSN. Measured values are used to calculate individual losses. The next part consists of creating a model for software analysis (Maxwell RMxprt). The generated model is converted into a 2D simulation environment (Maxwell 2D), where it is adapted to obtain values from the examined parts (rotor and stator teeth and rotor cage). Results of simulations at different loads are compared and analyzed from the point of view of higher harmonics.
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Calculation of parameters of small induction motor
Vojče, Zbyněk ; Cipín, Radoslav (referee) ; Vítek, Ondřej (advisor)
This bachelor thesis deals in the first part with a construction and a principle of function of an induction motor. In the second part deals with an actual analytical calculation of three-phase low power induction motor. Is performed a simulation in a program Ansoft RMxprt, which calculated the characreristics of the motor analytically and simulation in program Maxwell 2D by finite element method. The aim of the work is to compare results of simulations with results of analytical calculation.
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