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This paper aims to present a new wireless power transfer technique using capacitive coupling. The capacitive power transfer (CPT) system has been introduced as an attractive alternative to the traditional inductive coupling method. The CPT offers benefits such as simple topology, fewer components, better electromagnetic interference (EMI) performance and robustness to surrounding metallic elements.

A class-E inverter together with and without inductor capacitor (LC) matching circuit has been utilised in this work because of its ability to perform the DC-to-AC inversion efficiently with significant reduction in switching losses. The validity of the proposed concept has been verified by conducting a laboratory experiment of the CPT system.

The performances for both systems are analysed and evaluated. A 9.7 W output power is generated through a combined interface [printed circuit board (PCB) plate] capacitance of 2.82 nF at an operating frequency of 1 MHz, with 97 per cent efficiency for 0.25 mm coupling gap distance.

An efficient CPT system with class-E LC matching topology is proposed in this paper. With this topology, the zero-voltage switching can be achieved even if the load is different by properly designing the LC matching transformation circuit.

The paper presents the simplified model of the Class E inverter in which the MOSFET transistor is based on the piecewise‐linear (PWL) model. The model does not contain inductances. The PWL description makes it possible to obtain the model in the form of general closed formulae. The general formulae have been obtained by means of MATHCAD and verified with the IsSPICE^® simulator. The analysis of MOSFET switching performance in the active region at the constant load current is delivered. The work is a successive step in the systematic research of the Class E inverter as a supplying source in high frequency levitation heating/melting systems. The equivalent RL parameters of the load in such systems vary across a relatively wide range.

Induction heating applications aided by power electronic control have become very attractive in the recent past. For cooking applications, power electronics circuits are very suitable to feed power to multi loads with an appropriate control technique. The purpose of this paper is to develop a three leg inverter to feed power to three loads simultaneously and independently.

Pulse density modulation control technique is used to control the output power independently with constant switching frequency.

Multi-load handling converter with independent power control is achieved with reduced number of switching devices (two switches/per load) with simple control strategy.

The proposed system is simulated in MATLAB/Simulink, and the thermal analysis is carried out in COMSOL multi-physics software. The hardware realisation is performed for a 1 kW prototype with 20 kHz switching frequency and 10 kHz pulse density modulation frequency. PIC16F877A microcontroller is used to validate the experimental results for various values of control signals (D_PDM). The simulation and experimental results are in good agreement and validates the developed system.

The purpose of this paper is to examine diminish switching losses in a solar energy conversion system in order to utilise the full efficiency of a solar panel.

In this paper, a boost converter and a resonant DC link (RDCL) inverter are controlled by a microcontroller. The maximum power point tracker (MPPT) algorithm implemented for boost converter supplies to track maximum power point of solar panel. The Class D full-bridge resonant inverter (RI) that is considered to be supplied by boost converter is modeled and zero voltage switching operation is performed by controlling the inverter with sinusoidal pulse width modulation (SPWM) control scheme. The control algorithm is managed with a feedback detecting the current of the boost converter and the zero voltage levels of capacitor voltage in the resonant circuit.

There are several control techniques have been proposed to reduce switching losses and harmonic contents in conventional or RDCL inverters. Solar panels are used in low power applications among other renewable energy sources. By considering that the efficiency parameter of an actual solar panels is around 14∼17 per cent, the switching losses occurred in energy conversion systems causes the efficiency are reduced.

The proposed approach has been decreased the switching power losses owing to resonant DC link inverter while the developed MPPT algorithm provides to generate maximum power. This paper introduces a novel soft switching technique in solar energy applications in order to maximise the possible efficiency.

The purpose of this paper is to characterize the nonlinear dynamical behaviour of a buck‐based power‐switching amplifier controlled by fixed frequency and pulse width modulation with a proportional‐integral compensator. The system has two forcing frequencies and one natural frequency and therefore it is characterized by three different scales of time. When the frequencies are far one from the other, quasi‐static approximation can be used. However, as the switching and the modulating frequencies become closer, this approximation is not valid and the results based on it lead to erroneous conclusions about the dynamics of the system.

A discrete time approach is used to reveal the interesting nonlinear phenomena that the system can exhibit. From numerical simulations using the switched model, it is shown that the system can present period‐doubling bifurcation at the fast scale (switching frequency).

An exact solution discrete‐time model is derived, able to predict accurately the nonlinear dynamical behaviour of the system.

The discrete time model is obtained without making quasi‐static approximation. The exact switched model is used to validate the discrete‐time model obtained. Finally, the effect of the switching frequency instabilities on the output voltage spectrum has been explored.