Ahmad Saudi Samosir

Dynamic evolution control for synchronous buck DC–DC converter: Theory, model and simulation

Abstract This paper proposes a new control technique for synchronous buck DC–DC converter. Theory, design and implementation of the proposed control technique are provided. A new approach for converter controller synthesis based on dynamic evolution control theory is presented. In order to synthesize the converter controller, this method uses a simple analysis of nonlinear equation models of the converter. The synthesis process is simple and requires a quite low bandwidth for the controller. Therefore, this control method is suitable for digital control implementation. As an illustrative example, the synthesis of synchronous buck DC–DC converter controller is discussed in detail. The model of the synchronous buck DC–DC converter system was implemented using SimPowerSystems toolbox of MATLAB-SIMULINK. Performance of the proposed dynamic evolution control under step load change and step input voltage condition was investigated. Simulation results confirm that the proposed control method is superior to traditional PI based controller because of fast transient response and good disturbance rejection.

A new topology -Reversing Voltage (RV) - for multi level inverters

Multi level inverters have been widely accepted for high power high voltage applications. Their performance is highly superior to conventional two level inverters in reduced harmonic distortion, lower EMI (electro magnetic interference) and higher DC link voltages. However it has some disadvantages as increased number of components, complicated PWM control method, and voltage balancing problem at neutral point. In this paper a new topology called reversing voltage (RV) is proposed to improve the multi level performance by compensating the disadvantages already mentioned. This topology requires less components compared to available inverters (especially in higher levels) and requires less carrier signals and does not need balancing of the voltages. The topology and the control method based on PD (phase disposition) SPWM are shown and the required components are also compared to other topologies to show the superiority of the topology. Finally, output voltage and currents are demonstrated by simulation.

Dynamic evolution control of interleaved boost dc-dc converter for Fuel Cell application

An electric vehicle powered by the fuel cells called Fuel Cell Electric Vehicles has higher efficiency and lower emissions compared with the internal combustion engine vehicles. In this application, a high power boost dc-dc converter is adopted to adjust the output voltage, current and power of fuel cell engine to meet the vehicle requirements. The major challenge of designing a boost converter for high power application is how to handle the high current at the input and high voltage at the output. In this paper an interleaved boost dc-dc converter is proposed for stepping-up the voltage on high power application. The controller of converter system was designed. A new approach for interleaved boost converter controller based on dynamic evolution control theory is presented. Performance of the interleaved boost converter with the proposed dynamic evolution controller is tested through simulation.

Control of a bidirectional converter to interface ultracapacitor with renewable energy sources

This paper highlights the controller of a bidirectional converter to interface an ultracapacitor as storage device to renewable energy systems. Ultracapacitors are typically used in renewable energy systems to improve the systems reliability and energy conversion efficiency. The controller of the converter system has been designed and simulated based on the integration of both Current Mode Control and Linear Quadratic Regulator methods. The controller performance is tested under different modes of operating conditions in bidirectional converter using MATLAB/Simulink simulation package. The simulation results show that a good DC bus voltage regulation is achieved in the tested conditions. In addition to that, the controller ensures smooth transition between the buck and boost modes of the bidirectional converter operation.

A simple PEM fuel cell emulator using electrical circuit model

This paper presents the development of a simple emulator for proton exchange membrane (PEM) fuel cell. This emulator is built based on the dynamic model of PEM fuel cells using electrical circuits. The electrical circuit model has been modeled in Matlab Simulink environments. The double-layer charging effect characteristic inside the fuel cell is included in the models. The steady-state and transient response of the model is investigated. Emulator performance is validated using experimental data from a 500-W commercial PEM fuel-cell stack. The emulator could be used in PEM fuel-cell control related studies.

Modeling and analyzing the proton exchange membrane of fuel cell (PEMFC) in Matlab/SIMULINK environment

This paper presents and studies the mathematical model of proton exchange membrane of fuel cell (PEMFC) using Matlab/SIMULINK software. The paper consists of the calculation of cell voltage, the double layer charging effect, dynamic response and thermodynamic response. This model is used to analyze the fuel cell behavior and the characteristic of output values at different parameters. Two characteristics involved in this paper which are transient and steady-state condition where the results are presented in graphical representation. The parameters for this model in this paper are based on Ballard-Mark-V fuel cell. The maximum power produced by the fuel cell is 3757 watt at load current of 261.4 Amps.

Model of Pulse Power Generator in Electrical Discharge Machining (EDM) System

Electrical discharge machining (EDM) is a non-traditional manufacturing process of removing material. EDM system consists of a shaped tool and the work piece, which are connected to a power supply and placed in a dielectric fluid. EDM pulse power generator applies voltage pulses between the electrode and workpiece to generate sparks through the gap. The essential requirement for EDM system is to obtain the output waveform similar to the ideal EDM waveform. The design is based on transistor type pulse power generator circuit. This paper discuss in modeling of current and voltage gap waveform for EDM system.