Electrical equipment of sporting simulator

This paper describes development of stationary bike, which is able to produce and store electrical energy. Device consist of BLDC motor, used as generator, connected to stationary bike and power electronics managing the flow of the energy. Electrical energy from the generator can be stored in battery, used to supply external devices or as the last option “burned” in power resistor

History of feedback control

Předkládaná bakalářská práce má za úkol popsat historické milníky v oblasti vývoje a využití zpětné vazby od jejího prvního využití ve starověkém Řecku do příchodu moderních způsobů regulace po druhé světové válce. Zaměřuje se hlavně na regulátory, které byly ve své době významné, nebo důležité pro další vývoj. Dále je jejím účelem popis návrhu simulačního modelu Wattova regulátoru, který jsem vytvořil v programu Simulink, a návrh parametrů tohoto regulátoru pro regulaci elektromotoru.ObhájenoThis bachelors work describes historical milestones in the field of development and usage of feedback since ancient Greek, to discovery of modern ways of regulation after second world war. It pays attention mainly to regulators, which was significant in their times or important for future development. Next it describes simulation of watt regulator, which I made in program Simulink and designing parameters of this regulator for regulation of electric motor

Electrical equipment of sporting simulator

This paper describes development of stationary bike, which is able to produce and store electrical energy. Device consist of BLDC motor, used as generator, connected to stationary bike and power electronics managing the flow of the energy. Electrical energy from the generator can be stored in battery, used to supply external devices or as the last option “burned” in power resistor

Electric equipment of sports trainer

Předkládaná diplomová práce je zaměřena na návrh konceptu a technického řešení multifunkčního sportovního trenažeru, který by byl schopen vyrábět a uchovávat elektrickou energii. Hlavní částí práce je vytvoření simulačních modelů, které budou sloužit pro vývoj zařízení, a návrh elektroniky výkonové části trenažeru.ObhájenoThe master theses presents concept and final solution in design of multifunctional stationary bike which will be able to produce and store electrical energy. Main part of the thesis is devoted to developing of simulation models which will be used in design of the device, and design of power electronics part of the stationary bike

Adaptive control of LCL filter with time-varying parameters using reinforcement learning

Two main aspects of a LQ control of a single-phase converter with a LCL filter are studied in this paper. First, the choice of a penalization structure that prevents instability of the closed loop caused by input saturation due to limited voltage of the DC link. We show that all tested variants of the penalization can achieve stable performance of the system. Second, adaptation of the controller gains to a change of parameter of the LCL filter. We compare adaptation rules based on the classical Riccati equation and on the reinforcement learning method of the temporal difference gradient descent. The latter method has lower computational cost and the potential to be more extensible to non-linear systems. We show that the standard approach with a constant learning rate is inefficient and better results can be achievd using adaptive learning rate. Performance of the method with adaptive learning rate is tested in simulation of current tracking after step change of the output inductance

Real-time Algorithm for the Transformation of Multiple Harmonic Unbalanced Voltages into Symmetrical Components

The Fortescue theorem is a well-known transformation technique for parameter identification in three-phase systems. It is a valuable tool that transforms an unbalanced system into symmetrical components. This method itself can not be used in a real-time system because it needs to identify individual vectors of the voltage. The solution proposed in this paper is to combine the Fortescue theorem with a second-order generalized integrator (SOGI). The SOGI algorithm provides two functions. Firstly, it identifies voltage vectors. Secondly, it works as a band-pass filter. This means it can deal with the systems containing multiple harmonics, processing them individually. This paper evaluates the performance of the proposed algorithm, with a focus on harmonic selectivity and speed of the reaction during transients

Real-time Algorithm for the Transformation of Multiple Harmonic Unbalanced Voltages into Symmetrical Components

The Fortescue theorem is a well-known transformation technique for parameter identification in three-phase systems. It is a valuable tool that transforms an unbalanced system into symmetrical components. This method itself can not be used in a real-time system because it needs to identify individual vectors of the voltage. The solution proposed in this paper is to combine the Fortescue theorem with a second-order generalized integrator (SOGI). The SOGI algorithm provides two functions. Firstly, it identifies voltage vectors. Secondly, it works as a band-pass filter. This means it can deal with the systems containing multiple harmonics, processing them individually. This paper evaluates the performance of the proposed algorithm, with a focus on harmonic selectivity and speed of the reaction during transients

Integration of battery energy storage in thermal power plant

The paper focus on the benefits of close integration of battery based energy storage directly into thermal plants. The attention is paid to use of the energy storage for primary frequency control in cooperation with classical steam turbine control. The model topology of the turbomachinery with all modifications is described and discussed. Three case studies are investigated – the primary frequency control managed by either only turbine, only energy storage and by cooperation of both turbine and energy storage. The other benefits of integration energy storage into power plant systems are discussed in the conclusion

Experimental evaluation of three-phase voltage synchronization algorithms

This paper shows experimental results for three different methods used for a voltage synchronization to the threephase grid. Tested methods are: traditional phase locked loop using Clarke and Park transformation (SRF-PLL), dual econdorder generalized integrator phase locked loop (DSOGI-PLL) and sliding discrete Fourier transformation (sDFT). Experiments are carried out using controlled laboratory three phase power supply and show robustness of the methods to the noise, voltage distortion and sensitivity to grid frequency fluctuations. Finally, strong and weak aspects of the methods are discussed

Converter power losses computation by FPGA-based HIL simulator

Converter losses play a crucial role in the process of power converter design. Especially semiconductor components and heat sink selection are strongly dependent on the total power converter losses and thus affect the power converter size and its price. The most popular techniques for determination of the losses are based on the computer simulation of the power converter. These kinds of simulations could be very time consuming, because on one side, the simulation needs very short steptime for differential equations calculation to model power converter switching. On the other side, the temperature dynamics of heat sink are commonly slow and depend on power cycles of converter. With the help of FPGAbased hardware in the loop (HIL), the simulation could run real-time and it is possible to test different scenarios, different modulation techniques and see their influences on converter losses. This approach can lead to reduction of losses to the state, when it is possible to reduce the size of converter. Furthermore, the HIL simulation could be used for testing and developing control algorithm in real time conditions. It also offers flexibility in the easy change of model parameters and monitoring values which are not or hardly obtainable in real machine. This paper presents the FPGA-based HIL simulator of induction motor drive with three phase voltage source inverter based on Semikron IGBT modules