This page has only limited features, please log in for full access.
Deniss Stepins received the B.S., M.S. (Hons.), and Ph.D. degrees in electronics from Riga Technical University, Riga, Latvia, in 2004, 2006, and 2011, respectively. Since 2004, he has been with the Institute of Radio Electronics, Riga Technical University, where he is currently an Assistant Professor. In 2019 he also joined the Institute of Industrial Electronics and Electrical Engineering, where he is currently a postdoctoral researcher. He has authored or coauthored more than 50 research articles. His research interests include reduction of EMI generated by switch mode power supplies, low power converters, power factor correction, wireless power transfer systems, electronic components, sensors, and transducers. He serves as a Reviewer for two prestigious journals: IEEE TRANSACTIONS ON POWER ELECTRONICS and IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS.
A promising solution for inductive power transfer and wireless charging is presented on the basis of a single-phase three-level T-type Neutral Point Clamped GaN-based inverter with two coupled transmitting coils. The article focuses on the feasibility study of GaN transistor application in the wireless power transfer system based on the T-type inverter on the primary side. An analysis of power losses in the main components of the system is performed: semiconductors and magnetic elements. System modeling was performed using Power Electronics Simulation Software (PSIM). It is shown that the main losses of the system are static losses in the filter inductor and rectifier diodes on the secondary side, while GaN transistors can be successfully used for the wireless power transfer system. The main features of the Printed Circuit Board (PCB) design of GaN transistors are considered in advance.
Viktor Shevchenko; Bohdan Pakhaliuk; Oleksandr Husev; Oleksandr Veligorskyi; Deniss Stepins; Ryszard Strzelecki. Feasibility Study GaN Transistors Application in the Novel Split-Coils Inductive Power Transfer System with T-Type Inverter. Energies 2020, 13, 4535 .
AMA StyleViktor Shevchenko, Bohdan Pakhaliuk, Oleksandr Husev, Oleksandr Veligorskyi, Deniss Stepins, Ryszard Strzelecki. Feasibility Study GaN Transistors Application in the Novel Split-Coils Inductive Power Transfer System with T-Type Inverter. Energies. 2020; 13 (17):4535.
Chicago/Turabian StyleViktor Shevchenko; Bohdan Pakhaliuk; Oleksandr Husev; Oleksandr Veligorskyi; Deniss Stepins; Ryszard Strzelecki. 2020. "Feasibility Study GaN Transistors Application in the Novel Split-Coils Inductive Power Transfer System with T-Type Inverter." Energies 13, no. 17: 4535.
Taking into account the nonlinear properties of ferrites the output voltage of toroidal transformer with magnetically soft ferrite core is calculated. Calculations are based on methods analogous to those used in nonlinear optics. Initially demagnetized ferrite is assumed to be isotropic. At this condition apart from the harmonic on fundamental frequency the output voltage of transformer contains also higher harmonics of odd order. Nonlinear susceptibilities of third and fifth order are used in calculations Magnetic losses are taken into account considering linear and nonlinear susceptibilities as being complex. These losses affect amplitudes of harmonics in the output voltage of transformer and create phase shifts between components of magnetization on different frequencies in the core and the intensity of exciting harmonic magnetic field. Results obtained in calculations are confirmed by experimental measurement of output voltage of toroidal transformer with MnZn ferrite core. In order to calculate amplitudes of harmonics in the output voltage of transformer numerical values of susceptibilities in question should be known.
A. Gulbis; D. Malinovska; D. Stepins. Influence of losses on the output voltage of ferrite transformer in case of strong magnetic field in the core. IOP Conference Series: Materials Science and Engineering 2016, 108, 012023 .
AMA StyleA. Gulbis, D. Malinovska, D. Stepins. Influence of losses on the output voltage of ferrite transformer in case of strong magnetic field in the core. IOP Conference Series: Materials Science and Engineering. 2016; 108 (1):012023.
Chicago/Turabian StyleA. Gulbis; D. Malinovska; D. Stepins. 2016. "Influence of losses on the output voltage of ferrite transformer in case of strong magnetic field in the core." IOP Conference Series: Materials Science and Engineering 108, no. 1: 012023.
This paper is devoted to the analysis of the effect of switching frequency modulation (SFM) used for EMI reduction on the synchronous buck converters (SBC) parameters, such us output voltage ripples (OVR), peak power component currents, etc. In the paper SBC are studied analytically, using computer simulations and experimentally. The most careful attention is paid on the peak-to-peak OVR because it is the most problematic parameter due to the use of SFM. Several useful guidelines for the choice of SFM parameters and slight modification of the control circuit to get peak-to-peak OVR as small as possible are also proposed. The results presented in the paper can simplify the design of SBC with SFM.
Deniss Stepins. Analysis of switching frequency modulated synchronous buck converters. 2014 16th International Power Electronics and Motion Control Conference and Exposition 2014, 855 -860.
AMA StyleDeniss Stepins. Analysis of switching frequency modulated synchronous buck converters. 2014 16th International Power Electronics and Motion Control Conference and Exposition. 2014; ():855-860.
Chicago/Turabian StyleDeniss Stepins. 2014. "Analysis of switching frequency modulated synchronous buck converters." 2014 16th International Power Electronics and Motion Control Conference and Exposition , no. : 855-860.
In this paper conducted electromagnetic interference (EMI) of boost converter with switching frequency modulation (SFM) is theoretically analyzed in details. In the analysis line impedance stabilization network parameters, power inductor and input filtering capacitor parameters are taken into account. The analysis shows that the conducted EMI attenuation due to the use of SFM depends not only on modulation index as it is assumed in numerous research papers, but also on central switching frequency. Useful expressions to numerically calculate SFM boost converter conducted EMI spectrum and attenuation due to the use of triangular and sawtooth modulation waveforms are derived. Additionally experimental verification of the theoretical results is performed using a superheterodyne spectrum analyzer. Moreover a procedure for the choice of optimum SFM parameters (modulation waveform, frequency deviation and modulation frequency) to get maximum conducted EMI attenuation is proposed.
Deniss Stepins. Conducted EMI of Switching Frequency Modulated Boost Converter. Electrical, Control and Communication Engineering 2013, 3, 12 -18.
AMA StyleDeniss Stepins. Conducted EMI of Switching Frequency Modulated Boost Converter. Electrical, Control and Communication Engineering. 2013; 3 (1):12-18.
Chicago/Turabian StyleDeniss Stepins. 2013. "Conducted EMI of Switching Frequency Modulated Boost Converter." Electrical, Control and Communication Engineering 3, no. 1: 12-18.