DC-DC Boost Power Converter Research Articles

A Passivity-based Control Combined with Sliding Mode Control for a DC-DC Boost Power Converter

In this paper, a passivity-based control combined with sliding mode control for a DC-DC boost power converter is proposed. Moreover, a passivity-based control for a DC-DC boost power converter is also proposed. Using a co-ordinate transformation of state variables and control input, a DC-DC boost power converter is passive. A new plant is zero-state observable and the equilibrium point at origin of this plant is asymptotically stable. Then, a passivity-based control is applied to this plant such that the capacitor voltage is equal to the desired voltage. Additionally, the sliding mode control law is chosen such that the derivative of Lyapunov function is negative semidefinite. Finally, a passivity-based control combined with sliding mode control law is applied to this plant such that the capacitor voltage is equal to the desired voltage. The simulation results of the passivity-based control, the sliding mode control and the passivity-based control combined with sliding mode control demonstrate the effectiveness and show that the capacitor voltage is kept at the desired voltage when the desired voltage, the input voltage E and the load resistor R are changed. The results show that compared with the passivity-based control, the passivity-based control combined with sliding mode control has better performance such as shorter settling time, 8.5 ms when R changes and it has smaller steady-state error, which is indicated by the value of integral absolute error (IAE), 0.0679 when the desired voltage changes. The paper has limitations such as the assumed circuit parameters.

Passivity - based control using genetic algorithm for a DC-DC boost power converter

In this paper, a passivity – based control of a DC-DC boost power converter using genetic algorithm is proposed. The output of a DC-DC power boost converter is an inductor current. Its input is duty ratio . Using a co-ordinate transformation of state variables and control input, a DC-DC boost power converter is showed to be passive. A new plant is zero-state observable and the equilibrium point at origin of this plant is asymptotically stable. Then, a passivity - based control law is applied to this plant so that a voltage of capacitor x2 is equal to a value of desired voltage Vd when changing control input, duty ratio . The parameters of the passivity – based controller are also adjusted optimally by genetic algorithm using decimal encoder. Simulation results of a passivity – based control are good when the input voltage E, the load resistor R and the desired voltage Vd are varied. With variations of desired voltage Vd, the passivity – based controller supplies small value of IAE (integral absolute error of Vd and x2), small error, and short settling time Finally, simulation results show that the passivity – based control using genetic algorithm is better than the passivity – based control.

Modeling and Simulation of a Double-Stage Single-Phase Grid-Connected PV System

This paper presents the design model and simulation of a double-stage single-phase grid-connected PV system. This system includes an MPPT DC-DC boost power converter and a transformer-less single-phase DC-AC power inverter, which is connected to the power grid with an LCL filter. In the DC-DC boost converter, the Perturb and Observe algorithms are combined. The output voltage of the DC-DC converter is regulated, and the DC/AC output voltage is synchronized with the grid. The MATLAB-Simulink environment is used for the closed-loop simulation of the proposed setup. The simulation results are presented for various solar irradiance conditions and show that photovoltaic current is generated and matches the phase of grid voltage.

Reduced oscillations based perturb and observe solar maximum power point tracking scheme to enhance efficacy and speed of a photovoltaic system

This paper puts forward a reduced oscillation based perturb and observe (ROP&O) maximum power point (MPP) tracking (MPPT) technique to mitigate the probability of loss of tracking direction and to reduce oscillations around MPP when the solar photovoltaic (PV) array is subjected under periodically changing irradiance. The proposed technique retains the structure of conventional perturb and observe (P&O) technique additionally incorporating a unique structure of dynamic step sizing, along with proportional-integral (PI) controller which potently alters the duty cycle (𝐷) of the DC-DC boost power converter (BPC). The ROP&O MPPT technique is compared with conventional P&O and incremental conductance (IC) schemes in terms of tracking efficacy (𝜂), ripples in PV voltage and PV current, convergence time, and the error rates. The efficacy of the proposed scheme lies between 99.06% to 99.80%. Moreover, the time to obtain MPP is 0.018 sec. which is about five times faster than the P&O technique and fifteen times faster than the IC technique. Also, the proposed MPPT technique is benchmarked using three-phase grid integration, and the power quality of the grid current is observed in terms of total harmonic distortion (THD).

Simplified cascade multiphase DC-DC boost power converters for high voltage-gain and low-ripple applications

This paper proposes two new simplified cascade multiphase DC-DC boost power converters with high voltage-gain and low ripple. All simplifications reduce the number of active switching devices from <em>2N</em> into <em>N</em>, where <em>N</em> is the phase number. The first simplification reduces the number of inductors from <em>2N</em> into <em>N+1</em> and increases the number of diodes from <em>2N</em> into (<em>2N+1</em>). The second simplification reduces the number of inductors from <em>2N</em> into <em>N+1</em> and increases the number of diodes from <em>2N</em> into (<em>3N+1</em>). The second simplification needs inductors with smaller current rating than the first simplification. The expressions of output voltage as a function of load current are derived by taking into account the voltage drops across the inductors and switching power devices. Simulated and experimental results are included to show the basic performance of the proposed cascade multiphase DC-DC boost power converters.

A modified Cuk DC-DC converter for DC microgrid systems

A new efficient step-updirect current-direct current (DC-DC) power converter that is suitable for DC microgrid systems is proposed in this paper. The proposed step-up DC-DC converter is derived from the conventional Cuk DC-DC power converter. Output voltage analysis that is useful to predict the conduction losses is presented. It is shown that the proposed step-up DC-DC converter is more efficient than the conventional DC-DC boost power converter. Current ripple analysis that is useful to determine the required inductors and capacitors is also presented. Experimental results are included to show the validity of the proposed step-up DC-DC power converter.

Mutual and self-aging effects of power semiconductors on the thermal behaviour of DC-DC boost power converter

A shift from conventional to renewable resources has increased the importance of power exploitation via power converters. In this respect, estimating an accurate useful lifetime of power converters plays a major role for the manufacturers and users. This paper touches the issues related to the self and the mutual degradation effects of the power semiconductors such as IGBT and diode on each other in a conventional DC-DC boost converter. By IGBT and diode aging, junction-case thermal resistance, IGBT collector-emitter voltage and diode forward voltage have been increased leading to thermal operating point changes. These changes have a significant effect on the degradation and the useful lifetime of devices. It is shown that by either IGBT or diode aging due to the thermo-mechanical fatigue, an increase in the IGBT or diode junction temperature has been occurred. The results reveal the importance of mutual- and self-aging effects on the reliability assessment. An experimental validation has been also performed via a prototype setup of 200/400V 3000W DC-DC boost converter.

Revisiting the Teixeira Singularity Bifurcation Analysis: Application to the Control of Power Converters

For a discontinuous piecewise smooth (DPWS) dynamical system in [Formula: see text], whose state space is divided into two open regions by a plane acting as the switching manifold, there generically appear two lines of quadratic tangency, one for each involved vector field. When these two tangency lines have a transversal intersection, such a point is called a two-fold singularity. If furthermore, both tangencies are of invisible type, then the two-fold point is known as a Teixeira singularity (TS). The Teixeira singularity can undergo an interesting bifurcation, namely when a pseudo-equilibrium point crosses the two-fold singularity, passing from the attractive sliding region to the repulsive sliding region (or vice versa) and, simultaneously, a crossing limit cycle (CLC) arises. After deriving carefully a local canonical form, we revisit the previous works regarding this bifurcation thus correcting some detected misconceptions. Furthermore, we provide by means of a more direct approach the critical coefficients characterizing the bifurcation, also giving computational procedures for them. The achieved results are applied to some illustrative examples, within the realm of discontinuous piecewise linear (DPWL) systems. This family acts like a normal form for the bifurcation, since DPWL systems are able to reproduce all the unfolded dynamics. The study of TS-points in electronic DC-DC Boost power converters under a sliding mode control (SMC) strategy is addressed. Apart from being a relevant application, it allows to show the real usefulness of the analysis done.

Overview of Boost Converters for Photovoltaic Systems

DC-DC boost power converters play an important role in solar power systems; they step up the input voltage of a solar array for a given set of conditions. This paper presents an overview of the variance boost converter topologies. Each boost converter is evaluated on its capability to operate efficient, size, and cost of implementation. Conventional boost converter and interleaved boost converter are widely used topologies in photovoltaic systems reported; however, they have negative sides of varied efficiency level under changed weather conditions. Therefore, this paper proposes, interleaved boost converter with novel switch adaptive control, to maximise efficiency of standalone photovoltaic system under change of solar power levels, due to illadation condition.

On the Robust Control of DC-DC Converters: Application to a Hybrid Power Generation System

In this paper a complete robust control synthesis is performed for a hybrid power generation structure composed by a Fuel Cell and a Supercapacitor. The control strategies are applied to the DC-DC boost power converters associated to each power source. Multivariable PI control with H∞ performance, H∞ full and reduced order controllers are designed and compared. The multivariable PI controller is designed through an optimization procedure based on solving some Linear Matrix Inequalities. A μ-analysis and frequency/time response performances results shows the advantages of the different proposed control strategies.

Analysis and Improvement of a Passivity-Based Controller for DC-DC Boost Converters with Inductor Resistance

Output voltage regulation problem of DC-DC boost power converters is studied based on an averaged model with a practical inductor. This paper exploits the effect of inductor's parasitic resistance on the performance of an existing parallel-damped (PD) passivity-based controller (PBC) under load variations. As an attempt to apply the passivity-based framework to the converter with parasitic resistance we have combined a new proportional-integral (PI) controller with the PBC. Simulation results show that the combined (PBC and PI) dynamic output feedback controller successfully achieves the performance improvement under reference step changes and load variations.

Nonlinear Function Controller: A Simple Alternative to Fuzzy Logic Controller for a Power Electronic Converter

Recently, there has been an increase in the application of fuzzy logic controllers (FLCs) for control of power electronic converters. Due to the FLCs' complex algorithm, their realization often calls for a compromise between cost and performance. In this paper, it is shown that the rule table of most of the two-input FLCs used with power converters can be approximated into a single nonlinearity. This allows the controller to be easily realized using simple, fast, and inexpensive analog circuits. The simplified nonlinear function controller (NLFC) developed in this manner is shown to be equivalent in performance to the original FLC through simulations. The NLFC concept is then applied to PI-FLC, a type of FLC popular in power converter control applications. This results in the PI-FLC being replaced by a simple nonlinear PI controller (NPIC). Using this simplification, the design of NPICs to obtain good dynamic performance in power converters is explained. An example design of NPIC for controlling a dc-dc boost power converter is presented. Experimental results are also presented to demonstrate the superior dynamic performance of the converter with NPIC versus that of a linear-PI controller.

ON DYNAMIC PHENOMENA IN A DC-DC BOOST CONVERTER SUBJECT TO VARIABLE STRUCTURE CONTROL

In this paper, the dynamics of a DC-DC boost power converter under variable structure control is studied applying bifurcation analysis techniques. The switching hyperplane coefficients are considered as bifurcation parameters. The dynamic phenomena detected in this work suggest new types of sliding bifurcations. This analysis is relevant in the context of sliding mode control with auxiliary adaptive strategies, since bifurcation analysis is a suitable tool to investigate global stability.

A new high-power-factor three-phase AC-DC converter: analysis, design, and experimentation

This paper proposes a new high-power factor three-phase AC-DC power converter, which is composed of a line interphase transformer (LIT) and two three-phase diode rectifiers, followed by a pulsewidth modulation (PWM) DC-DC boost power converter. The active switch of the boost converter is gated at a constant frequency such that the AC input current is discontinuous. This procedure provides an input current shaping without the third, fifth and seventh harmonics. The currents that flow through the LIT and boost inductors have such a high-switching frequency that ferrite cores with a small size can be utilized. In addition, the output voltage is regulated by PWM to compensate for line voltage variations and load change. Theoretical analysis, design procedure and example, along with experimental results taken from a 6 kW laboratory prototype are given.