Design zero-voltage switching DC-DC buck converter

This report proposes an integrated, high switching frequency, zero-voltage-switching dc-dc buck converter for battery charger application. The design and analysis of dc�dc buck converter with integrated inductor is presented. The converter has been optimized to convert 12V input voltage to 5V at 1.5A maximum load current at 50MHz switching frequency. The converter has been simulated using an ORCAD 16.5 based simulation tool and result show that the switching losses using zero�voltage-switching technique is less compared to conventional buck converter

Voltage tracking of a DC-DC buck converter using neural network control

This master report presents a voltage tracking of a neural network for dc-dc buck converter. The mathematical model of Buck converter and artificial neural network algorithm is derived. The dc-dc Buck converter is designed to tracking the output voltage with three variation. This master report consists open loop control, closed loop control and neural network control. The Buck converter has some advantages compare to the others type of dc converter. However the nonlinearity of the dc-dc Buck converter characteristics, cause it is difficult to handle by using conventional method such as open loop control system and close loop control system like proportional-integral-differential (PID) controller. In order to overcome this main problem, a neural network controller with online learning technique based on back propagation algorithm is developed. The effectiveness of the proposed method is verified by develop simulation model in MATLAB-Simulink program. The simulation results show that the proposed neural network controller (NNC) produce significant improvement control performance compare to the PID controller for both condition for voltage tracking output for dc-dc Buck converter

System uncertainties estimation based adaptive robust backstepping control for DC DC buck converter

This paper proposed a novel adaptive robust backstepping control scheme for DC-DC buck converter subjected to external disturbance and system uncertainty. Uncertainty in the load resistance and the input voltage represent the big challenge in buck converter control. In this work, an adaptive estimator for matched and mismatched uncertainties based backstepping control is applied for DC-DC buck converter. The updating laws are determined based on the lyapunov theorem. Thus, the difference between the estimated parameters and actual parameters converges to zero. The proposed control method is compared with the conventional sliding mode control and integral sliding mode control. Simulation results demonstrate the effectiveness and robustness of the proposed controller

Nonlinear controller design for a buck converter

This thesis presents five different nonlinear control techniques for voltage regulation of a DC-DC buck converter operating in continuous conduction mode. A state space averaging model is derived from a non-ideal buck converter circuit with the consideration of resistances of each component. Based on this model, different nonlinear control techniques have been developed to control the DC-DC buck converter. These include backstepping control, sliding mode control, backstepping sliding mode control, adaptive backstepping control, and adaptive backstepping sliding mode control. All these proposed controllers have been evaluated by computer simulation and implemented on the DC-DC buck converter which is built for this thesis. Simulation and experimental results show that all the proposed controllers are able to stabilize the closed loop system and to achieve satisfactory voltage regulation performances under source voltage variations and load changes

Digital Pulse Width Modulation Controlled DC-DC Buck Converter using VHDL Coding

This paper presents the control of the DC-DC Buck converter using Digital Pulse Width Modulation (DPWM) methods in MATLAB-SIMULINK using XILINX TOOL. The conventional PWM is compared with the Digital Pulse Width Modulation. The DPWM generators like Counter based Digital Pulse Width Modulation (CDPWM); Delay-line based Digital Pulse Width Modulation (DDPWM) and Hybrid based Digital Pulse Width Modulation (HDPWM) are coded using VHDL. The DPWM generator is used for the control and analysis of the DC-DC Buck converter. The time transient analysis of the DPWM techniques are evaluated and compared.

Dynamic modeling of a hybrid electric system based on an anion exchange membrane fuel cell

The main topic of this paper is the dynamic modeling of a hybrid energy system based on an anion exchange membrane fuel cell (AEMFC). The objective was to develop a dynamic model, able to describe the system behavior and the response of components to sudden load changes. The overall model design includes other different subsystems, represented by electric dipoles or double dipoles. In addition to the two power sources, AEMFC and battery pack, there is a DC-DC buck converter, interjected between them, whose function is to decrease AEMFC voltage to bus voltage set by a battery pack and to smooth this voltage, thereby serving the load properly. Above all, there is a step time-varying dc load and a power management block, for the managing of energy flows through the system. The whole model was implemented in Matlab–Simulink environment. The main outputs of DC-DC buck converter and battery dynamic models were validated respectively with the data of other equally detailed reference simulation models and with experimental data found in the literature. In this paper, the design of a discrete intervals power management strategy to manage the connection/disconnection of the AEMFC was made and the hybrid managed energy system calculation code was used to evaluate the time trends of AEMFC and battery pack electric powers, of battery pack state of charge, of DC-DC buck converter and entire hybrid system efficiencies for different initial battery pack states of charge and different step time-varying dc loads

A study on EMI noise source modeling with voltage source in synchronous DC-DC buck converter

Y. Saito, T. Ibuchi, T. Funaki, K. Kawai and T. Tsuda, "A study on EMI noise source modeling with voltage source in synchronous DC-DC buck converter," 2020 IEEE 11th International Symposium on Power Electronics for Distributed Generation Systems (PEDG), Dubrovnik, Croatia, 2020, pp. 470-475, doi: 10.1109/PEDG48541.2020.9244423

Fractional Modeling and Analysis of Buck Converter in CCM Mode Peration

In this paper fractional order averaged model for DC/DC Buck converter in continues condition mode (CCM) operation is established. DC/DC Buck converter is one of the main components in the wind turbine system which is used in this research. Due to some practical restriction there weren’t exist input voltage and duty cycle of converter therefor whole of the wind system was simulated in Matlab/Simulink and gathered data is used in proposed method based on trial and error in order to find the fractional order of converter. There is an obvious relationship between controller performance and mathematical model. More accurate model leads us to better controller

Loss Model for Gallium Nitride DC-DC Buck Converter

In recent years, more research has been done on Enhancement Mode Gallium Nitride (eGaN) converters, as the world is moving towards more power efficient converters. Power converters play a major role in efficiently controlling and converting electric energy used by machines, systems, and everyday products. The process to make converters more efficient was complicated and slow in the twentieth century. One of the important aspects in power electronics is to evaluate different losses and minimize losses to achieve high efficiency of the converter. With help of simulation tools such as MATLAB and LTspice, this process has become much faster and reliable in the modern era. A model for estimating power losses for eGaN DC-DC buck converter (12V/1.2V) is illustrated in this paper. This loss model was calculated for different frequencies, and compared experimentally and theoretically. This paper also investigated the constant variables, which help realize the difference between theoretical and experimental losses in eGaN DC-DC buck converter. Pre-prints of this article have been previously made available [1-4]

Measurement and simulation of conducted disturbances on DC power grids of a HVDC system with an active DC/DC converter

With the increasing of the distributed generation, DC microgrids have become more and more common in the electrical network. To connect devices in a microgrid, converter are necessary, but they are also source of disturbances due to their functioning. In this thesis, measurement and simulation of conducted emissions, within the frequency range 2-150kHz, of a DC/DC buck converter are studied