The dc-dc converters with high step-up DC-voltage gain play a vital role in integrating low voltage DC sources. Though several converter topologies are reported in the recent past, attempts have been made to reduce the components, especially the switching devices, passive elements, converter losses, etc., of the converter. A novel DC-DC converter topology, viz., single switched impedance network (SSIN)-based converter with n-stage is proposed in this paper. The operation of the SSIN based converter in continuous and discontinuous conduction modes are discussed. The effect of parasitic elements on DC-voltage gain and efficiency of the SSIN is carried out. The small-signal model of the SSIN converter is derived. The performance of the SSIN converter is compared with the similar converter topologies. The 500 W prototypes of the SSIN with n = 1 and n = 2 are fabricated, and the experimental results are presented in this paper. To improve the converter performance, SiC-based semiconductor devices are used. The SSIN converter with two-stage has low switch loss at 500 W load, improved efficiency during high power and high output voltage operation, the switch stress of V _o /2, etc.

In grid-connected solar PV, the size and cost become higher due to the presence of a transformer. This transformer deteriorates the entire solar PV system efficiency. To overcome this limitation, a switched capacitor-inductor network (SCLN) based ultra-voltage gain dc-dc converter using a single switch is presented in this paper. The SCLN converter can achieve ultra dc-voltage gain with minimum number of devices when compared to other existing converters. Moreover, the voltage gain is significantly improved at entire duty ratios. In addition, due to switched approach of inductor and capacitor, the converter provides lesser ripple content in the output voltage and current. The operation of the converter in CCM and DCM are discussed. The parasitic elements are considered to estimate the dc-voltage gain and the efficiency of the converter more precisely. The small-signal model of the converter is derived, and the pole-zero locations are investigated. Moreover, the comparative performances of SCLN converter with existing converters are reported. A hardware prototype has been developed and tested. To prove the applications of the SCLN converter in solar PV system, the experimental results are observed by considering the output voltages of i) 650 V for three-phase and ii) 325 V for single-phase applications.

Many topologies in the area of non-isolated high-voltage gain dc–dc converter are reported for improving efficiency and voltage gain and to reduce the switch stress with the use of minimum number of components. A family of quadratic high-gain dc–dc converters using an extended capacitor–diode network is proposed in this article, and an extensive analysis has been conducted to assess their performances. The output voltage of the five proposed converters by considering the effect of parasitic elements is derived, and the analytical efficiency profiles are drawn. The proposed converters are designed for 650 V, 0.5 kW, and 50 kHz with a 48-V input source. The hardware prototypes are fabricated for the five converters, and the experimental results are presented. For the considered design, converters I and III give higher efficiency and lower voltage stress on the semiconductor devices. Converters IV and V are suitable for higher voltage gain applications. A dynamic model for converter I is derived and a controller is implemented for closed-loop operation. A suitable converter among the family can be selected according to the applications for the integration of renewable energy sources.

The implementation of a non-isolated dual input bridge type DC-DC converter for hybrid energy source integration is discussed in this paper. The proposed converter accommodates two sources using an inductor, a capacitor, two IGBTs without the anti-parallel diode and two IGBTs with the anti-parallel diode. The different modes of operation of the converter are explained with detailed analytical waveforms and equivalent circuits. From the analysis, the steady state output equation of the converter is derived. The boundary condition between the CCM and DCM operations is also derived. The dynamics of the converter is analyzed in detail with help of a small signal model. The step response of different transfer functions is discussed. The computer simulations of the proposed converter topology have been carried out using MATLAB/Simulink?. An experimental prototype of the proposed converter is also built and tested successfully in the laboratory environment. Performance comparison of the proposed converter is carried out with the conventional converter topologies in terms of component counts, efficiency, loss breakdown, and power density.

Biomass based hybrid energy system is utilized for the electrification of villages, especially in developing countries like India. Hybrid Energy System (HES) components, feasibility study, and cost analysis are presented in this paper for a remote area Kakkavayal, a forest region in Kerala, India. A water stream at 25 m height has been identified at Kakkavayal by the Forest Department of Kerala. The village has been marked to study hourly measured meteorological and load data for a period of time. The performance of the proposed hybrid system is determined on hourly basis and optimum configuration, which can meet the energy demand with minimum cost using the hybrid system design tool HOMER. Parametric analysis indicates that with 2 kW solar PV, 15 kW pico-hydel, and 5 kW biomass gasifier generator together with five numbers of 12 V, 200 Ah of battery storage to meet the primary load demand of 56 kWh/d and 17 kWh/d (scaled annual average) of deferrable load. From the simulation, the cost of energy is found to be Rs 7.274 (US$ 0.164) per kWhr. The cost of energy of the proposed HES is also compared with the diesel-based HES. It is found that economically, the proposed HES is a very good alternative for present pico-hydel/diesel system.