A Modified Step-Up Converter with Small Signal Analysis-Based Controller for Renewable Resource Applications

Abstract

Solar energy is one of the most important renewable sources due to its advantages such as simple structure, convenient installation, diverse applications, and low maintenance costs. Low power generation is the main concern with solar panels, so the maximum transmission of this power is a prime priority. The design of boost converters with the ability to generate high voltage gain, efficient structure, and stable and low-cost control circuits is the first step after installing these panels. This study presents a simple and high-gain design of a step-up converter, which uses only one power switch. The significance of this issue is when it will be apparent to know that each switch needs a separate control circuit and complex systems require more control topologies. In comparison with the conventional converter, the gain of the proposed converter, with the use of two additional diodes, a capacitor, and an inductor, was five times greater than the gain of a classical converter with 80% of the duty cycle. The proposed converter can solve the narrow turn-off period problem for the power semiconductor components in order to achieve higher DC voltages that are possible at higher duty cycles in classical converters. Small signal analysis of the proposed converter is presented and a controller based on steady-space matrixes is presented. The reaction of the proposed controller is considerable since a deep mathematical analysis supports this controller. The principal operations of the proposed converter and the projected controller were analyzed mathematically and verified with the help of MATLAB/SIMULINK. Additionally, hardware implementation of the proposed converter was done on a laboratory-scale around 100 W.

A transformer‐less single‐switch boost converter with high‐voltage gain and mitigated‐voltage stress applicable for photovoltaic utilizations

“…An interesting result that easily can track by this figure is the voltage on the capacitor C 4 that is equal to the total of the voltages on the capacitors C 3 and C 5 . This state had been predicted by the Equation (9). Figure 12 shows the comparative curves to evaluate the efficiency of the proposed converter and the converters presented in Table 1 theoretically.…”

“…Also the cathode of this diode is connected to the capacitor C 1 that has a positive voltage and greater than the input voltage. This section of the converter is the input side of the quadratic boost converters that have been analyzed in detail in many researches already 9,16,35 . This voltage will charge the inductor L 2 through the power switch.…”

“…4,5 For this reason, various structures have been proposed to increase the voltage. Converters such as conventional boost, [6][7][8][9] buck-boost, [10][11][12] fly-back, 13,14 and Cuk 15,16 have not high-voltage gain, and electromagnetic interference (EMI) and diode back-flow problems can be seen in these converters because the high-voltage gain can be obtained in higher duty cycles for the power switches. Generally, power converters are time-varying nonlinear systems, and due to the uncertainty of the converter parameters, their ability to be accurately modeled in all operating conditions is extremely difficult, so the control process for the power converters is always a major challenge for designers.…”

“…This section of the converter is the input side of the quadratic boost converters that have been analyzed in detail in many researches already. 9,16,35 This voltage will charge the inductor L 2 through the power switch. Figure 2 is presented to give more details for this working state.…”

Maximum Power Point Tracking by the Small-Signal-Based PI and Fuzzy Logic Controller Approaches for a Two-stage Switched-Capacitor DC-DC Power Boost Converter; Applicable for Photovoltaic Utilizations

“…Some investigators have worked on limitation switching loss while others have researched to limit conductivity loss. The researchers continue their research to get higher performance from the converters and to increase the voltage gain [16][17][18][19][20].…”