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This paper aims to propose a novel integrated control method (ICM) for high-power-density non-inverting interleaved buck-boost DC-DC converter. To achieve high power conversion by conventional single phase DC-DC converter, inductor value must be increased. This converter is not suitable for industrial and high-power applications as large inductor value will increase the inductor current ripple. Thus, two-phase non-inverting interleaved buck-boost DC-DC converter is proposed.

The proposed ICM approach is based on the theory of integrated dynamic modeling of continuous conduction mode (CCM), discontinuous conduction mode and synchronizing parallel operation mode. In addition, it involves the output voltage controller with inner current loop (inductor current controller) to make a fair balancing between two stages. To ensure fast transient performance, proposed digital ICM is implemented based on a TMS320F28335 digital signal microprocessor.

The results verify the effectiveness of the proposed ICM algorithm to achieve high voltage regulating (under 0.01 per cent), very low inductor current ripple (for boost is 1.96 per cent, for buck is 1.1) and fair input current balance between two stages (unbalancing current less than 0.5A).

The proposed new ICM design procedure is developed satisfactorily to ensure fast transient response even under high load variation and the solving R right-half-plane HP zeros of the CCM. In addition, the proposed method can equally divide the input current of stages and stable different parallel operation modes with large input voltage variations.

A two switches non-isolated DC-DC novel buck-boost converter for charging the battery of electric vehicle is projected in this paper. The performance of the converter is compared with conventional buck-boost and transformer-less P/O buck-boost converter by Shan and Faqiang. The detail operation and performance analysis of the proposed converter is described both in continuous conduction mode and discontinuous conduction mode. A state space model and simulation model is designed in MATLAB. The PID controller parameters are tuned using Single-objective Salp swarm optimization algorithm using MATLAB. The controller is implemented using DSP board. The hardware and simulation results are projected in the paper to validate the effectiveness of the proposed buck-boost converter. A comparison analysis is projected among conventional converter and Shan & Faqiang converter.

The converter state space model is designed and simulation model is also developed in MATALAB. The controller is implemented using DSP board. The parameters are obtained using optimization technique using SSA algorithm. The hardware design is also implemented, and the result is compared with the Shan and Faqiang converter. The efficiency of the converter is also tested.

The converter is providing a higher efficiency. The inductor current is also positive in both buck and boost mode. The robustness of the controller is better for a wide range of variation of input voltage because the output voltage remains almost constant. Therefore, this is very suitable for battery charging and PV module application.

For battery charging from PV module where voltage fluctuation is frequent.

The authors can use household applications to charge the battery using PV module.

The converter design concept is new. Optimization is used to find the parameters of the controllers and is implemented in hardware design. The parameters obtained provide robustness in the converter performance.

At first, the organic/inorganic and hybrid PV materials by their electrical model are described. Then the proposed converter topology, circuit analysis and various operating modes of converter according to on/off timing of switches are investigated. The current and voltage in the converter components are illustrated and the voltage gain and switching stress of proposed converter are presented. Finally, to show the effectiveness of the proposed converter, the power loss analysis is provided and the simulation is done in PSIM software. In the last section, the advantages of the proposed topology of higher efficiency by lower number of components in compare with other conventional topologies are presented.

In this paper, an improved topology of DC-DC converter based on VL technique is proposed for Perovskite Solar cells (PeSCs). The PeSCs attracted a lot of interest due to their potential in combining the advantages of both organic and inorganic components. The proposed converter by using fewer components and higher output voltage generation in compare with conventional ones could be a good candidate for PeSCs due to lower efficiency of this cells. The performance of converter is expressed in continuous conduction mode (CCM) and discontinuous conduction mode (DCM), and the boundary conditions for the proposed converter is presented.

By using VL technique, this converter is used to boost the lower output voltage levels of PeSCs for grid connection. The PV cell output voltage is increased from 24.5 V to 106 V by proposed converter topology. The step-by-step voltage increasing by charging and discharging of inductor and capacitor is used for boosting the input voltage. By comparing other converters, there is no design complexity in the proposed converter structure, and the power loss is much reduced which increases the converter efficiency. On the other hand, due to using lower number of elements of energy storage elements such as inductors and capacitors, the converter cost is also diminished. Therefore, the design topology simplicity which result simple control algorithm and lower number of components which diminish the system cost by appropriate voltage boosting capability are the main advantages of this proposed topology for new PeSCs which don’t have enough efficiency in compare with old Si PV cells.

In this paper, by using the lower number of components a new structure of DC-DC converter based on the VL technique is proposed. The advantages of this converter such as the simplicity, easier control and high voltage gain by lower power loss, could make this converter a good candidate for new PeSCs where the system whole efficiency will be a critical point to have the unique properties of this new materials in lower loss.

Traditionally, industrial power supplies have been exclusively controlled through analog control to sustain high reliability with low cost. However, with the perpetual decrement in cost of digital controllers, the feasibility of a digitally controlled switch mode power supply has elevated significantly. This paper aims to outline the challenges related to the design of digital proportional-integral (PI) controlled synchronous rectifier (SR) buck converter by comparing controller performance in continuous and discrete time. The trapezoidal approximation-based digital PI control is designed for low voltage and high-frequency SR buck converter operating under continuous conduction mode.

The analog and digital controller are designed using a SISO tool of MATLAB. Here, zero-order hold transform is used to convert the transfer function from continuous to discrete time. Frequency and time domain analysis of continuous plant, discrete plant and close loop system is performed. The designed digital PI control is simulated in MATLAB Simulink. The simulated results is also verified on hardware designed around digital signal processing control.

The continuous and discrete control loops are validated with multiple tests in the time and frequency domain. The detailed steady state theoretical analysis and performance of the SR buck converter is presented and verified by simulation. It is found that the delay in digital control loop results in a low phase margin. This phase margin decreases with higher bandwidth. The hardware experiments with the digital control loop are carried out on a 10 W prototype. The chosen parameters for the SR buck converter are found to be optimum for steady and transient state response.

This paper compares the digital and analog control approach of compensator design. It focuses on the implications created at the time of transforming the control design from continuous to discrete time. Further, it also focuses on the selection of parameters such as phase margin, bandwidth and low pass filter.

This study aims to propose a new non-isolated Multi-Input Zeta-SEPIC (MIZS) dc–dc converter for renewable energy sources integration with different voltage levels (low-voltage source, high-voltage source). The chosen configuration of the converter is capable of performing bucking as well as boosting operations in various modes of operation.

Parameters of the selected MIZS converter are designed using the time-domain analysis. The selected converter belongs to the sixth-order family with two switches and six energy storage elements. State-space model of the converter is developed for each mode of operation, and using these individual state-space models, an average state-space model of the converter useful to carry out detailed analysis for different operating conditions is developed. Analysis related to operational stability of the converter is also carried out using Participation Factor (PaF)-based Eigen value analysis.

Using the PaF-based Eigen analysis, participation of the various state variables in different Eigen modes and vice versa is carried out. Performance of the converter for different parameter variations in the allowable range is determined and the same has been used to find the operational stability of the converter under different modes of operation. The selected converter has low inductor ripple currents and output voltage ripples when delivering the power to load.

Because operational stability of the converter under various operating conditions is one of the key performance indicators for selecting a particular type of converter, PaF-based Eigen value analysis has been carried out using the average state-space model developed for the selected MIZS converter. Operational stability analysis of the converter is carried out for parameter variations also. In addition, participation of the various states in each Eigen mode and vice versa have been analyzed for designed parameter values and also variation within the specified range of variations.

The purpose of this study is to design a more flexible and larger range of the dimming circuit that achieves the independence of multiple LED strings drive and can time-multiplex the power circuit.

The state-space method is used to model the BUCK circuit working in Pseudo continuous conduction mode, analyze the frequency characteristics of the system transfer function and design the compensation network. Build a simulation platform on the Orcad PSPICE platform and verify the function of the designed circuit through the simulation results. Use Altium Designer 16 to draw the printed circuit board, complete the welding of various components and use the oscilloscope, direct current (DC) power supply and a signal generator to verify the circuit function.

A prototype of the proposed LED driver is fabricated and tested. The measurement results show that the switching frequency can be increased to 1 MHz, Power inductance is 2.2 µH, which is smaller than current research. The dimming ratio can be set from 10% to 100%. The proposed LED driver can output more than 48 W and achieve a peak conversion efficiency of 91%.

The proposed LED driver adopts pulse width modulation (PWM) dimming at a lower dimming ratio and adopts DC dimming at a larger dimming ratio to realize switching PWM dimming to analog dimming. The control strategy can be more precise and have a wide range of dimming.

The purpose of this paper is to suggest a new analytical methodology for transient analysis of DC‐DC power converters. The closed‐form solution obtained following this methodology is suitable both for design of passive elements of the converter and for the development of control techniques.

The methodology is based on a mixed use of Laplace transform and z‐transform. The expressions of variables of the set of equations, characteristic of a DC‐DC converter, are first evaluated in the Laplace domain for the generic switching interval. The solutions obtained are then z‐transformed in order that they match in each contiguous time interval, to form the complete transient response.

The new solution methodology allows the analytical determination of time constants of DC‐DC converters, also in presence of large duty‐cycle variations. Moreover, it is possible to evaluate easily the influence of passive elements on converter's behaviour, without several numerical simulations.

The analytical solution of linear systems is well known both in transient and in steady‐state conditions. However, when there is an infinite number of poles in the Laplace transform of the input signals, such as the case of switching power converters, the inversion in a closed form of the Laplace transform of the solution can be cumbersome. The methodology presented tries to overcome this problem by using an approach based on the z‐transform. Operating in this way, a closed‐form solution can be obtained both in transient and in steady‐state conditions, for all the main topologies of switching power converters. The procedure has been explained in detail for the sample case of boost DC‐DC converters.

This paper is devoted to the quasi‐Z‐source (qZS) converter family. Recently, the qZS‐converters have attracted high attention because of their specific properties of voltage boost and buck functions with a single switching stage. As main representatives of the qZS‐converter family, this paper aims to discuss the traditional quasi‐Z‐source inverter as well as two novel extended boost quasi‐Z‐source inverters.

Steady state analysis of the investigated topologies operating in the continuous conduction mode is presented. Input voltage boost properties of converters are compared for an ideal case. Mathematical models of converters considering losses in components are derived. Practical boost properties of converters are compared to idealized ones and the impact of losses on the voltage boost properties of each topology is justified. Finally, the impact of losses in the components on the boost conversion efficiency is analyzed.

To demonstrate the impact of component losses on the overall efficiency of the qZS‐converter, a number of experiments were performed. The impact of inductor winding resistance was compared with the forward voltage drop of qZS‐network diodes. It was found that the forward voltage drop of diodes has the highest effect on the efficiency. If the diodes are replaced with high‐power Schottky rectifiers with a low forward voltage drop (UD=0.6 V), the effective efficiency rise by at least 5 percent could be expected for all three qZS‐converter topologies. For the same operating parameters and component values, the traditional qZS‐converter had the highest efficiency of the qZS‐converter family. The boost converter was compared with the traditional qZS converter in terms of efficiency. It was found that the boost converter has an efficiency 2 percent higher in the boost operation mode and approximately the same efficiency in the non‐boost operation.

The paper provides a good theoretical background for further practical studies. qZS‐converters have voltage boost and buck functions with a single switching stage, which could be especially advantageous in renewable energy applications.

The paper presents a detailed study of the qZS‐converter family. Mathematical models of converters considering losses in components are derived. It is the first time the boost converter is compared with the qZS converter.

The purpose of this paper is to enhance the response of quadratic boost converter inverter system (QBCIS) and also investigate proportional integral (PI) and fractional order proportional integral derivative (FOPID)-based space vector modulation inverter (SVMI) systems.

This paper presents modern expansion in control methods and power electronics have created wind-based AC to AC converters that relays to AC drives. The process includes the flow of quadratic boost converter (QBC) and SVMI locate their technique in associating permanent magnet synchronous generator and three phase load. This effort conveys with digital simulation using MATLAB/Simulink and hardware implementation of current mode wind-based QBCIS.

The direct current (DC) output from the rectifier is boosted using Quadratic Boost Converter (QBC). The DC yield of QBC is provided to the SVMI. The alternating current (AC) yield voltage is attained by using three-phase filter. The investigations are done with PI and FOPID-based SVMI systems. Current mode FOPID control is proposed to improve the time response of QBCIS system.

The simulation results are compared with the hardware results of QBCIS. The results of the comparison of PI with FOPID controlled by converters are made to show the improvement in terms of settling time and steady-state error.

Control-signal-to-output-voltage transfer function of the conventional boost converter has at least one right-half plane zero (RHPZ) in the continuous conduction mode which can restrict the open-loop bandwidth of the converter. This problem can complicate the control design for the load voltage regulation and conversely, impact on the stability of the closed-loop system. To remove this positive zero and improve the dynamic performance, this paper aims to suggest a novel boost topology with a step-up voltage gain by developing the circuit diagram of a conventional boost converter.

Using a transformer, two different pathways are provided for a classical boost circuit. Hence, the effect of the RHPZ can be easily canceled and the voltage gain can be enhanced which provides conditions for achieving a smaller working duty cycle and reducing the voltage stress of the power switch. Using this technique makes it possible to achieve a good dynamic response compared to the classical boost converter.

The observations show that the phase margin of the proposed boost converter can be adequately improved, its bandwidth is largely increased, due to its minimum-phase structure through RHPZ cancellation. It is suitable for fast dynamic response applications such as micro-inverters and fuel cells.

The introduced method is analytically studied via determining the state-space model and necessary criteria are obtained to achieve a minimum-phase structure. Practical observations of a constructed prototype for the voltage conversion from 24 V to 100 V and various load conditions are shown.