Analiza dizajna LCLC rezonantnog invertera za dvostupanjsko dvofazno napajanje

This paper deals with the design analysis and synthesis of power resonant inverter with sinusoidal output voltage for sensitive loads. The proposed filter must be capable of removing higher harmonic components from the supplying voltage to reach a harmonic distortion of roughly 5% in the whole range of the load (0 − 100%). The inverter can be supplied from either single-phase voltage inverter in full- or half- bridge connection, or from simple DC/DC buck converter. Non-symmetrical control causes higher harmonic content, both odd and even. Simulation and experimental results based on designed parameters and subsequently obtained from Matlab and OrCad models confirm good quality of output quantities, voltage and current.Tema je ovog članka analiza dizajna i sinteza učinskog rezonantnog invertera sa sinisuidalnim izlaznim naponom za osjetljive terete. Predloženi filtar mora moći filtrirati više harmonike ulaznog napona kako bi distorzija harmonika bila oko 5% u čitavom radnom području (0−100%). Inverter se može napajati ili iz jednofaznog naponskog invertera u mosnom ili uzrokuje pojavu viših harmonika u signalu, kako parnih tako i neparnih. Simulacijski i eksperimentalni rezultati temeljeni na sintetiziranim parametrima dobivenim od modela napravljenih u programskim paketima Matlab i OrCad potvr.uju dobru kvalitetu izlaznih veličina napona i struje

ZVS operating region of multiresonant DC/DC boost conveter

Electromagnetic phenomena that occur during stable operation in resonant circuits of multiresonant ZVS boost converter are described, which can be applied in many fields of the needs of DC voltage electricity. The operating region of the converter is defined which assures the circuit’s operation in which semiconductor elements are switched at zero voltage (ZVS). Conditions delimiting the ZVS operating region are provided. Analysis of the circuit’s operation is based on results of simulation testing by means of Simplorer software

Mathematical model of thyristor inverter including a series-parallel resonant circuit

The article presents a mathematical model of thyristor inverter including a series-parallel resonant circuit with the aid of state variable method. Maple procedures are used to compute current and voltage waveforms in the inverter

Variable rotational speed control system of sewage pumping station

Cascade and variable rotational speed control systems of sewage pumping stations are compared in this article. The range of pump efficiency variations and potential for breakdowns are adopted as criteria. A pumping station including two or three pumps is analysed. A control system at a variable rotational speed and maximum sewage level is presented. Properties of a cascade control system and a system at a maximum head of sewage are compared using the example of any pump performance chart

Commutation processes in multiresonant ZVS bridge converter

The analysis of the multiresonant ZVS DC/DC bridge converter is presented. The control system of the converter is based on the method of frequency control at the constant time of transistor turn-off with a phase shift. The operation of the circuit is given and the operating range of the converter is defined where ZVS switching operation is assured. Control characteristics are given and the converter’s efficiency is defined. The circuit’s operation is analysed on the basis of results of the converter simulation tests using Simplorer programme

Analysis of high-frequency ZVS (zero voltage switched) multiresonant converters

The paper presents chosen issues of multiresonant ZVS DC/DC converters for use in transport devices. It provides results of mathematical analysis, simulation and experimental testing of selected multiresonant ZVS DC/DC conversion circuits. The paper explores the theory of the multiresonant DC/DC conversion circuits in consideration of single-transistor topologies. In the end conclusions are presented

The induction-cage motor efficiency determination for variable speed working

Energy-efficient industrial drives and control systems are designed to minimize power consumption. Energy consumption is associated with the efficiency of energy conversion in electric motors. In the paper the in-service efficiency estimation method for induction cage motor was shown. The implementation of the method was based on the air-gap torque method. The results were compared with those obtained with the known air-gap torque method. The authors present a significant impact of estimation of mechanical power losses and stray load losses in the motor on the accuracy of estimating the coefficient of efficiency cage induction motor

Multiresonant ZVS CUK convertor

The article presents properties of multiresonant ZVS Cuk converter. The control system of the converter is based on PWM technique. The operating range of the converter is defined where ZVS operation is assured. Control characteristics are given and the converter’s efficiency is defined. The converter’s operation is analysed on the basis of simulation testing

Multiresonant ZVS boost converter

The article presents properties ofmultiresonant voltage-increasing converter to be ! applied in DC voltage supply systems. The configuration of the system elements enables application ! of the technique of zero voltage switching (ZVS) of semi-conductor elements, which yields high operating frequencies of the system while maintaining high energy efficiency and reliability of operation. Results of simulation tests of the converter, based on Simplorer, are discussed. Regulation characteristics are presented and the converter's efficiency is determined

The concept of applying class E resonant inverter to induction heating of railway turnouts

The article discusses class E zero-voltage-switching resonant inverter (ZVS) to be applied in induction heating of railway turnouts. The resonant circuit of the inverter is subject to mathematical analysis using the method of state variables. Results of simulation testing, based on Simulink and Simplorer software, of an inverter at the operating frequency of 100 kHz are presented