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In presented paper a technique for the secondary side power stabilisation for contactless energy transfer systems is presented. The original part of this approach is the position where stabilisation is performed. Instead of complicated pickup side modifications all additional circuits are located on the systems transmitting side.

Paper describes the system design of modern power electronics laboratory test stands intended for electrical engineering schools and universities. Proposed system design simplifies the configuration of the lab and maximizes the time that the students can use for experimental measurements and converter characterization. System pre-configuration is constant for all exercises so the students do not need to learn the system design of every particular test stand. It also provides clear measurement readings and protection loops so number of errors or damages of the hardware during testing is minimized.

In the paper a stepper motor closed loop driver algorithm is presented which emphasizes the processor overhead minimization in which it is implemented, as well as rotor average torque and set position acquisition. The program was tested as a simulation in MATLAB environment and on a physical driver based on 32 bit microcontroller connected with a motor and an encoder. Exemplary results are introduced in the work.

PurposeThe purpose of this paper is to introduce a unique multilevel, one‐phase inverter (in the multiplied full‐bridge configuration, cascaded‐type) with unequal voltage distribution among the voltage levels.Design/methodology/approachNumerical and experimental results are discussed and the topology thereafter evaluated.FindingsUnequal voltage distribution among voltage stages of the converter leads to increase of the output voltage resolution while simplifying the converter construction and minimizing the power switch losses. Simplorer numerical analyses as well as test stand measurements were led in order to verify properties of the system. Using the voltage distribution in the proportion of 6/2/1 leads to improved utilisation of power switches used in the means of voltage, current and switching frequency. FFT analysis was implemented in order to explore the frequency domain properties of the control apparatus.Practical implicationsThe results allow improvement of power switch utilisation and output voltage resolution of cascaded, three‐stage multilevel converter topologies and voltage output filter optimisation for multilevel power electronic converters.Originality/valueA new concept of voltage distribution is provided and described, a dedicated DSP‐based control system was developed as well as a small‐scale converter prototype, test stand measurement results are provided.

Voltage – current characteristics of photovoltaic (PV) generators rely on many auxiliary conditions as irradiance, temperature or load profile. Independently on the type of installation (stand-alone, grid connected, hybrid) a solar panel generation system should always be operated at it's maximum electrical power point under defined conditions. Many algorithms have been proposed as maximum power point seeking techniques. A comparison of two methods is described considering an iterative approach and a fuzzy logic controller. Both dynamical properties and tracking accuracy are analyzed based on laboratory experiments and measurements led on an exemplary installation. In addition a misinterpretation avoidance apparatus is proposed for flat-topped power characteristics under partial shading or low irradiance. Power electronic system is described as well as the control system prototype based on a fixed-point microcontroller. Measurement results are presented and conclusions are given.

Contactless power supply systems are of high interest in small power and large power applications. Many high efficiency contactless systems use the resonant operation mode. A parallel compensation system is presented enlarging overall system safety and allowing for resonant system parameter change while maintaining zero current switching (ZCS) operation. Basics of digital control unit construction and operation are presented. Simulation and experimental results are given for control system operation. Systems performance allows for large resonant circuit parameter drift. Modern DSP control unit minimizes the necessary external circuitry and time delays in case of most important operations. DOI: http://dx.doi.org/10.5755/j01.eee.20.10.4989

This paper presents the topology of the high voltage, pulsed converter using transformer parasitic parameters. The converter uses solid-state switches and generates (in no load conditions) a voltage pulse with an amplitude of 20 kV with 5kV supply. The steepness of the voltage rise without load is 1.36 kV/ns and the pulse duration is less than 100ns.

In the article a converter topology for high voltage, nanosecond pulse generation is introduced. Proposed topology uses parasitic parameters of autotransformers as circuit components. Introduced converter was used to generate Pulsed Corona Discharge (PCD). Numerical analysis and results of laboratory measurements of the properties of proposed topology are presented. The voltage pulse was obtained with a duration less than 100ns, voltage amplitude of 15.3kV, with the power of 4kV. The peak power delivered to the reactor amounted to 260kW.

Nowadays non-thermal plasma technologies are state of the art for the generation of ozone as an important oxidant for water cleaning or bleaching, the incineration of waste gases or for the removal of dust from flue gases in electrostatic precipitators. Furthermore their possibilities of gas depollution are well known. Plasmas contain reactive species, in particular ions, radicals or other oxidizing compounds, which can decompose pollutant molecules, organic particulate matter or soot. Electron beam flue gas treatment is another plasma-based technology which has been successfully demonstrated on industrial scale coal fired power plants. This chapter aims a comprehensive description of plasma-based air remediation technologies. The possibilities of exhaust air pollution control by means of non-thermal plasmas generated by gas discharges and electron beams will be summarized. Therefore plasma as the 4th state of matter, its role in technology and the principle of plasma-based depollution of gases the will be described. After an overview on plasma-based depollution technologies the main important techniques, namely electron beam flue gas treatment, gas discharge generated plasmas including plasma-enhanced catalysis and injection methods will be described in separate sections. In these sections selected examples of commercially available or nearly commercialised processes for flue gas treatment or the removal of volatile organic compounds and deodorization will be described, too. Current trends and concepts will be discussed.

For non-thermal plasma technology corona discharge devices high-voltage, high-current pulses are used with very high demands considering rising voltage slopes. Many solid state pulse power modulator (SSPPM) system topologies are known however most include a high power transformer compromising the overall system efficiency. A modified Fitch generator topology is introduced enlarging the output voltage to supply voltage ratio to theoretically the factor of three. Moreover the output voltage waveform enables the magnetic pulse compressor cross-section minimization with the factor of 0,67 due to a unique output voltage waveform. Test stand results are given for a 10-stage construction and a single stage magnetic compressor, power switch dynamic parameters influence on systems efficiency is discussed.