Resonant Converters

Using a pulse density modulation (PDM) for regulating and stabilization of a transistor converter’s load current for induction heating equipment, with the number of pulses during a modulation period divisible to the half-period of an inverter’s output voltage is considered in this paper. A mathematical model of the resonant voltage inverter under PDM and analytical equations for maximum and minimum current amplitudes and their difference determining the swing of the ripple current’s amplitude were obtained. It is made clear that PDM with the number of pulses during a modulation period which is divisible to the half-period of the inverter output voltage allows, on average, to reduce the swing of the ripple current’s amplitude and enlarge the regulation range of the load current.

This paper explains the implementation of a small-signal model for a new five-level series resonant inverter structure. The proposed circuit combines the advantages of multilevel inverters and the characteristics of the physical phenomena, resonance. The small-signal model offers the possibility to design a linearized linear time-invariant (LTI) model around an equilibrium point based on the first-order Taylor series. After that, the performance of the proposed five-level series resonant inverter and its small-signal model are evaluated in MATLAB/Simulink environment. Compared with a MATLAB model generated using the system identification toolbox, the developed small-signal model exhibited a good accuracy in frequency and time domains. In addition, a hardware test bench is developed to validate the proposed model. Both simulation and experimental results show that the proposed multilevel resonant inverter is very interesting for high-voltage high-frequency applications. As a perspective, from the results obtained, we suggest the use of small-signal AC analysis for multilevel series resonant inverter modeling. The paper contains rich information on the recently used tools for dynamic systems modeling and analysis of nonlinear processes that can be applied to modeling and analyzing other power electronics inverters.

Aujourd’hui, La technique des convertisseurs à résonance représente une partie de recherche importante, recherche liée également à des applications performantes et puissantes tels que les alimentations de secours, ozoneurs et les chauffages par induction. Il y a plusieurs types de convertisseur résonant, tel que : l’onduleur à résonance série, onduleur à résonance parallèle, convertisseur de résonance de classe E, redresseur de résonance de classe E, convertisseur résonant à commutation de tension nulle, convertisseur résonant à commutation de courant zéro, convertisseur résonant à deux quadrants. Dans ce travail nous sommes intéressé à l’étude et la conception d’un onduleur à résonance série, l’étude commencée par la description de système et la topologie proposée ensuite une simulation et réalisation de l’onduleur effectué, les signaux de commande sont implémenté par la carte arduino uno, la comparaison entre les résultats de simulation et expérimentaux nous donne une concordance et avec la carte de commande nous pouvons avoir des signaux de commande en hautes fréquences.
Keywords—La résonance; Onduleur; Haute frequence; Arduino

the power generated from the renewable sources like solar energy produces is a direct current. This DC power needs to be converted to alternate current power, as most of the appliances use AC power, circuit which convert DC power into AC power at desired output voltage and frequency are called as inverters. Like all power, its needs to be under control. The digital control has been popular, is a branch of control theory that uses digital computers to act as system controllers. The use of digital control of electrical equipment increasing. Recently years, digital control has been greatly used in different applications such as the power transmission. Compared to traditional analogue control, digital control of inverter has many advantages. The main objective of this work is the realization of half bridge resonant inverter and controlled with arduino. The digital control is tested in proposed inverter and the results obtained show the efficiency of digital control by the arduino board.
Keywords—Inverters; Power Electronics; Digital control; Arduino.

Application of soft switching in DC-DC converter has achieved a remarkable success in power electronics technology in terms of reduction in switching losses, improve in power density, minimization of electromagnetic interference (EMI) and reduction in the volume of DC-DC converters. Quite a number of soft switching techniques had been reported in the past four decades. This paper aims at providing a review of various soft switching techniques, based on topology, the location of the resonant network, performance characteristics, and principles of operation. In addition, converters area of application, advantages as well as limitations are also highlighted.

The study and use of solid state transformers (SST) has grown exponentially, and new technologies are being developed every day. The application of a series resonant converter in a SST allows improvement of its efficiency, through soft switching of the power switches. The present paper proposes a bidirectional topology capable of receiving an AC voltage in its input, and delivers the same AC voltage on its output through a series resonant converter and a push-pull AC-AC converter, with all switches operating with soft switching. The converter has three different switching elements and is capable of adjusting the output voltage level by changing the switching frequency. In this paper, the description of the converter's operation and simulation results are presented. A prototype is being built to be tested in laboratory.

Harvesting electricity from low frequency vibration sources such as human motions using piezoelectric energy harvesters (PEH) is attracting the attention of many researchers in recent years. The energy harvested can potentially power portable electronic devices as well as some medical devices without the need of an external power source. For this purpose, the piezoelectric patch is often mechanically attached to a cantilever beam, such that the resonance frequency is predominantly governed by the cantilever beam. To increase the power generated from vibration sources with varying frequency, a multiresonant PEH (MRPEH) is often used. In this study, an attempt is made to enhance the performance of MRPEH with the use of a cantilever beam of optimised shape, i.e., a cantilever beam with two triangular branches. The performance is further enhanced through optimising the design of the proposed MRPEH to suit the frequency range of the targeted vibration source. A series of parametric studies were first carried out using finite-element analysis to provide in-depth understanding of the effect of each design parameters on the power output at a low frequency vibration. Selected outcomes were then experimentally verified. An optimised design was finally proposed. The results demonstrate that, with the use of a properly designed MRPEH, broadband energy harvesting is achievable and the efficiency of the PEH system can be significantly increased.

This study focuses on the appropriate design of the inductive elements of the LLC converter based on a typical industrial approach, i.e. assuming to use standard parts available on the market from qualified manufacturers. At first, a methodology to select the passive components is presented, highlighting the difference between the external inductor solution and the magnetically integrated solution. Secondly the step-by-step procedure used for the design of the high frequency transformer is illustrated. The possibility to integrate the resonant inductors into the HF transformer is then analysed, presenting different solutions. Finally a comparison between a classical and an integrated design is then presented referring to a case study; thus permitting to endow the potential benefits of the integrated solution.

Basic methods of frequency control voltage-source series-resonant inverter induction heating equipment were considered. A comparative analysis of a phase-locked loop (PLL) systems and approaches in design them for voltage-source series-resonant inverter were presented. Analytical expressions for determining an optimal current switching transistor of voltage-source series-resonant inverter, time of transistor's recharge parasitic capacitances with snubber's capacitance, as well as the delay time between the control signals of the transistor, and time which corresponds to the phase shift between the input signals of the phase detector PLL are established.

This book seeks to consider why quantum physics and relativity do not work as a system. It considers if an underlying nondimensional system exists, that we each perceive as dimensional particle reality through our individual perceptions of reality. There is no proven theory of the physical fundamental nature of reality. Are we non-dimensional possibility infinitely divided by a wholeness or oneness of the vibration of the Universe, which then becomes either possible or probable in our dimensional particle experience of reality? This book is for those wanting to consider new ways of looking at the nature of reality.

This paper proposes a non-isolated soft-switching bidirectional DC/DC converter for interfacing energy storage in DC microgrid. The proposed converter employs a half-bridge boost converter at input port followed by a LCC resonant tank to assist in soft-switching of switches and diodes, and finally a voltage doubler circuit at the output port to enhance the voltage gain by two times. The LCC resonant circuit also adds a suitable voltage gain to the converter. Therefore, overall high voltage gain of the converter is obtained without a transformer or large number of multiplier circuit. For operation in buck mode, the high side voltage is divided by half with capacitive divider to gain higher step-down ratio. The converter is operated at high frequency to obtain low output voltage ripple, reduced magnetics and filters. Zero voltage turn-on is achieved for all switches and zero current turn-on and turn-off is achieved for all diodes in both modes i.e., buck/boost operation. Voltage stress across switches and diode is clamped naturally without external snubber circuit. An experimental prototype has been designed, built and tested in the laboratory to verify the performance of the proposed converter.

In this paper a single-switch power supply based on the shunt class E amplifier is presented. A simple and easy method to analyze the complete system is proposed and one way to provide compensation to parameter's variation of the ozone generator and to reduce the size of the resonant inductor is proposed and studied too. The selected topology offers a low-cost and high-power density source that efficiently supplied the system. Experimental results are congruent with the specifications and a high ozone concentration is obtained.

Abstract: Resonant LCL-T converter can operate as stable
voltage source, being fed from current, for instance, the
photovoltaic battery. It is shown that LCL-T resonant tank has
intrinsic ability to convert stable AC current into stable AC
voltage thus parametrically regulating output voltage at a fixed
value. This mode of operation is made possible by the use
of active (synchronous) rectifier to recoup energy from the
output back to the LCL-T resonant tank. Basic characteristics
of resonant LCL-T converter regulated by phase shift between
inverter and rectifier regardless of a solar battery current drift
have been defined. It is shown that phase control guarantees
0 voltage and 0 current on switching; however, turn-off
current could be substantial. Calculations and assumptions
made in this study have been confirmed by simulation and
hardware prototype.

This paper presents a modified C-dump converter for brushless DC (BLDC) machine application in the flywheel energy storage system. The proposed converter can realize the energy flowing from source to BLDC machine flywheel and BLDC machine with fly wheel to load. The energy extracted from the turnoff phase of the BLDC machine is to be recovered by C-dump converter. The system principle of operation, modelling, and control strategy has been discussed in this paper. This paper also investigated Simulation and experimental results of the proposed system. KEYWORDS Brushless DC (BLDC) machine, c-dump converter, flywheel energy storage system.

In this paper a single-switch power supply based on the shunt class E amplifier is presented. A simple and easy method to analyze the complete system is proposed and one way to provide compensation to parameter's variation of the ozone generator and to reduce the size of the resonant inductor is proposed and studied too. The selected topology offers a low-cost and high-power density source that efficiently supplied the system. Experimental results are congruent with the specifications and a high ozone concentration is obtained.

The main disadvantage of a pulse-density-modulated (PDM) voltage-source series-resonant inverter (SRI) is that the amplitude of the SRI output current fluctuates. To reduce the fluctuation, this paper presents an augmented PDM control method for the SRI. The proposed augmented PDM reduces the fluctuation in the amplitude of the SRI output current and requires fewer PDM sequences compared to the irregular PDM, and also provides a more uniform pulse density difference between PDM sequences compared to the inconstant PDM.

Application of soft switching in DC-DC converter has achieved a remarkable success in power electronics technology in terms of reduction in switching losses, improve in power density, minimization of electromagnetic interference (EMI) and reduction in the volume of DC-DC converters. Quite a number of soft switching techniques had been reported in the past four decades. This paper aims at providing a review of various soft switching techniques, based on topology, the location of the resonant network, performance characteristics, and principles of operation. In addition, converters area of application, advantages as well as limitations are also highlighted.

This work highlights a modular power conditioning system (PCS) in photovoltaic (PV) applications which consists with a DC-DC converter. The converter is able to regulate and amplify the input DC voltage produced by the PV panal. The implementation of Mosfet as bidirectional switch on the converter yields greater conversion ratio and better voltage regulation than a conventional DC-DC step up converter and PWM resonant converter. It also reduces the switching losses on the output DC voltage of the converter, as the MOSFET switches on primary winding of converter switch on under ZVS conditions. The proposed resonant converter has been designed, with the modification of series resonant converter and PWM boost converter that utilizes the high frequency of AC bidirectional switch to eliminate the weaknesses of used converters. The topology of the proposed converter includes the mode of operations, designing procedure and components selection of the new converter elements. This topology provides a DC output voltage to the inverter at range of about 120Vac-208 Vac.

The aim of this research work is to obtain analytical expressions that allow analyzing the dual-frequency current of the induction coil, as well as, the currents of the inverters for the “two inverter power supplies” converter topology. To take into account the frequency-dependent parameters of an induction heater load, their implementation is shown through series-parallel connections of frequency-independent resistances and inductances. A simulation study is performed to verify the obtained analytical expressions of the currents.

Harvesting electricity from low frequency vibration sources such as human motions using piezoelectric energy harvesters (PEH) is attracting the attention of many researchers in recent years. The energy harvested can potentially power portable electronic devices as well as some medical devices without the need of an external power source. For this purpose, the piezoelectric patch is often mechanically attached to a cantilever beam, such that the resonance frequency is predominantly governed by the cantilever beam. To increase the power generated from vibration sources with varying frequency, a multiresonant PEH (MRPEH) is often used. In this study, an attempt is made to enhance the performance of MRPEH with the use of a cantilever beam of optimised shape, i.e., a cantilever beam with two triangular branches. The performance is further enhanced through optimising the design of the proposed MRPEH to suit the frequency range of the targeted vibration source. A series of parametric studi...

In this paper a single-switch power supply based on the shunt class E amplifier is presented. A simple and easy method to analyze the complete system is proposed and one way to provide compensation to parameter's variation of the ozone generator and to reduce the size of the resonant inductor is proposed and studied too. The selected topology offers a low-cost and high-power density source that efficiently supplied the system. Experimental results are congruent with the specifications and a high ozone concentration is obtained.

Worked out mathematical model allows to perform the operation analysis of transistor voltage inverter with LF pulse
modulation at different combinations n, m, s. In order to verify the validation of tolerance concerning the analysis by first harmonic and findings accuracy, computer simulation of the operation of series-resonant transistor voltage inverter with LF pulse modulation (pulse density modulation) at LF-PWM and LF-PFM (n=1 & n=2) was performed. Dependence of mathematical model maximum error on resonant-circuit Q-factor was obtained.

Various Resonant Converters for high voltage and high power applications have been designed. Different Topologies of LLC, LCC, and CLL Resonant Converters have been simulated and compared for the same input voltage. The simulation was done at a very high frequency. The Output Power and the Efficiency of all the three Resonant Converters were calculated.With the results, it has been proved that LCC Resonant Converters were very much suited to give an output voltage of around 62 Kilovolts with a output power of 20 kilowatts.

In this paper, analysis and modelling of a single-phase cascaded full-bridge resonance inverter are considered. The control of proposed inverter by full-wave phase method at high frequency is implemented. In the first step, MATLAB/Simulink environments are used to simulate the model and show obtained results of waveforms. The second step is the experimental validation of simulation results by a realization of the inverter and generated signals. The Root-Mean-Squared voltage of a capacitor waveform between 3 and 7 kHz frequency with simulation and realization are presented, comparatively, for a comparison. The results obtained are satisfactory and show the efficiencies of analysis and the proposed model of the full-bridge resonance inverter.