1,271 research outputs found
Drive systems for operation on deep-sea ROVs
Power systems for thruster actuators and other auxiliaries employed on work-class deep-sea ROVs subject to 300bar ambient pressures, are considered. Emphasis on 3Ă3 matrix converters for thrusters and 3Ă2 matrix converters for system auxiliaries, is given, along with experimental results showing operation during pressure cycling consistent with typical operational duties
Modulated predictive control for indirect matrix converter
Finite State Model Predictive Control (MPC) has been recently applied to several converter topologies as it can provide many advantages over other MPC techniques. The advantages of MPC include fast dynamics, multi-target control capability and relatively easy implementation on digital control platforms. However, its inherent variable switching frequency and lower steady state waveform quality, with respect to standard control which includes an appropriate modulation technique, represent a limitation to its applicability. Modulated Model Predictive Control (M2PC) combines all the advantages of MPC with the fixed switching frequency characteristic of PWM algorithms. The work presented in this paper focuses on the Indirect Matrix Converter (IMC), where the tight coupling between rectifier stage and inverter stage has to be taken into account in the M2PC design. This paper proposes an M2PC solution, suitable for IMC, with a switching pattern which emulates the desired waveform quality features of Space Vector Modulation (SVM) for matrix converters. The switching sequences of the rectifier stage and inverter stage are rearranged in order to always achieve zero-current switching on the rectifier stage, thus simplifying the current commutation strategy
Eksperimentalno ponaĹĄanje prototipa matriÄnog pretvaraÄa izvedenog s novim energetskim modulima
This paper describes the design and the solutions adopted for a matrix converter prototype of 10 kW, based on new integrated power modules. The performance of the converter is verified by means of experimental tests.Älanak opisuje projekt i rjeĹĄenja usvojena za prototip 10 kW matriÄnog pretvaraÄa, izvedenog s novim integriranim energetskim modulima. Svojstva pretvaraÄa provjerena su eksperimentalnim ispitivanjima
Experimental efficiency comparison between a direct matrix converter and an indirect matrix converter based on efficiency using Si IGBT and SiC MOSFETs
This paper presents an experimental efficiency comparison study between two different direct AC-AC converter topologies: a direct matrix converter (DMC) and an indirect matrix converter (IMC). The evaluation is performed under variable load conditions using both discrete Silicon (Si) IGBTs and Silicon Carbide (SiC) MOSFETs working at power levels up to 9 kW. Each loss measurement is carried out using two power analyzers: one placed at the input and one at the output of the converter under study. To facilitate this measurement an output filter was necessary in addition to the normal input filter. Both converters are modulated the same traditional symmetrical space vector approach and feature an identical input/output filter design
Eksperimentalno ponaĹĄanje prototipa matriÄnog pretvaraÄa izvedenog s novim energetskim modulima
This paper describes the design and the solutions adopted for a matrix converter prototype of 10 kW, based on new integrated power modules. The performance of the converter is verified by means of experimental tests.Älanak opisuje projekt i rjeĹĄenja usvojena za prototip 10 kW matriÄnog pretvaraÄa, izvedenog s novim integriranim energetskim modulima. Svojstva pretvaraÄa provjerena su eksperimentalnim ispitivanjima
Modulation Strategies for Indirect Matrix Converter: Complexity, Quality and Performance
In general, there are two main classifications in matrix converters. The most common known type is conventional matrix converter (CMC) or direct matrix converter (DMC). The other type is indirect matrix converter (IMC). A brief review for modulation strategies are provided in this work for modulation strategies in IMC. There are several popular modulation methods for IMC such as carrier-based modulation and space vector modulation (SVM). A sinusoidal current waveform is produced on the input and output sides to implement the modulation method. In the conclusion the modulation methods will compared based on performance, theoretical complexity, and some other parameters
Construction and analysis of causally dynamic hybrid bond graphs
Engineering systems are frequently abstracted to models with discontinuous behaviour (such as a switch or contact),
and a hybrid model is one which contains continuous and discontinuous behaviours. Bond graphs are an established
physical modelling method, but there are several methods for constructing switched or âhybridâ bond graphs, developed
for either qualitative âstructuralâ analysis or efficient numerical simulation of engineering systems. This article proposes a
general hybrid bond graph suitable for both. The controlled junction is adopted as an intuitive way of modelling a discontinuity in the model structure. This element gives rise to âdynamic causalityâ that is facilitated by a new bond graph notation. From this model, the junction structure and state equations are derived and compared to those obtained by
existing methods. The proposed model includes all possible modes of operation and can be represented by a single set
of equations. The controlled junctions manifest as Boolean variables in the matrices of coefficients. The method is more
compact and intuitive than existing methods and dispenses with the need to derive various modes of operation from a
given reference representation. Hence, a method has been developed, which can reach common usage and form a platform for further study
Bond graph models of DC-DC converters operating in both CCM and DCM
In this paper, Bond Graphs are employed to develop a novel mathematical model of conventional switched-mode DC-DC converters valid for both continuous and discontinuous conduction modes. A unique causality bond graph model of hybrid models is suggested with the operation of the switch and the diode to be represented by a Modulated Transformer with a binary input and a resistor with fixed conductance causality. The operation of the diode is controlled using an if-then function within the model. The extracted hybrid model is implemented on a Boost and Buck converter with their operations to change from CCM to DCM and to return to CCM. The vector fields of the models show validity in a wide operation area and comparison with the simulation of the converters using PSPICE reveals high accuracy of the proposed model, with the Normalised Root Means Square Error and the Maximum Absolute Error remaining adequately low. The model is also experimentally tested on a Buck topology
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