This paper proposes a multi-stage power generation system suitable for renewable energy sources, which is composed of a DC-DC power converter and a three-phase inverter. The DC-DC power converter is a boost converter to convert the output voltage of the DC source into two voltage sources. The DC-DC converter has two switches operates like a continuous conduction mode. The input current of DC-DC converter has low ripple and voltage of semiconductors is lower than the output voltage. The three-phase inverter is a T-type inverter. This inverter requires two balance DC sources. The inverter part converts the two output voltage sources of DC-DC power converter into a five-level line to line AC voltage. Simulation results are given to show the overall system performance, including AC voltagegeneration. A prototype is developed and tested to verify the performance of the converter.

In this article, a novel topology of DC-DC converter based on voltage multiplier cell and coupled inductor with higher efficiency and low blocking voltage across semiconductor is proposed for renewable energy application. The recommended topology obtains a high voltage gain using voltage multiplier cell and one coupled inductor. Only one power switch is utilized in this structure, which reduces the converter's cost. The other benefits of this converter are low number of components, high efficiency due to the zero-voltage switching and the zero-current switching of diodes, and low blocking voltage of the power switch and diodes. Besides, the voltage multiplier cell acts as a passive clamp circuit and reduces the voltage stress across the power switch. Thus, a low rated power switch can be used in the presented topology. Due to the zero-current switching in Off-state, the reverse recovery problem of diodes is reduced. To illustrate the performance and superiority of the presented topology, operation modes, steady-state and efficiency analysis, and the comparison study with other similar converters are presented. Finally, a 160~W experimental prototype with 50~kHz switching frequency and 17 V input voltage are built to confirm the theoretical investigation and effectiveness of the proposed converter.

The share of DC-based Renewable energy Resources (RERs) and electricity storage systems are increasing due to developments of smart grid technologies. Moreover, the share of DC-based load has rapid growth due to significant developments of power electronic technologies. Therefore, a more flexible power system is required for efficient integration of emerging loads and generators. In this paper, hybrid AC-DC Local Network (LN) is incorporated as an appropriate topology versus conventional AC LN to reinforce the integration of RERs and Plug-in Hybrid Electric Vehicles (PHEVs). A mixed integer linear model is developed for operation of both hybrid AC-DC LN and conventional AC LN topologies considering high penetration of RERs and PHEVs. This operation model is solved by GAMS optimization software to minimize the operation cost and find the optimum inter-resource scheduling in the dayahead market. Moreover, investment analysis and reliability assessment are carried out for the mentioned LNs. Numerical study is conducted to evaluate the ability of both topologies for better utilizing the opportunities of integration.

This research paper has aimed to provide an insight into developing a control strategy for a standalone wind energy conversion system (SWECS) intended to power a DC load. The system mainly consists of the wind turbine (WT), generator, power electronics devices, battery bank, and its charging control circuit along with pitch angle control of wind turbine. Charging of battery is attained through tip-speed ratio (TSR) MPPT logic. DC-DC converter acts as a charge controller which charges the battery in a controlled way. Pitch angle control mechanism generates appropriate pitch angle command to dampen the rotational speed of the wind turbine. It limits the turbine output power, generator speed and rectifier output voltage during high wind speed ensuring electrical and mechanical safety of the wind turbine. The three-phase self-excited induction generator (SEIG) coupled with a wind turbine is used to produce electrical power. It is connected to load via the AC-DC-DC converter to obtain regulated voltage at the load side. The efficacy of control logic developed for proposed wind energy conversion system is tested in MATLAB/Simulink platform varying wind and load profile.

With the growing movement of using direct current (DC) load demands, as well as DC distribution generations (DGs), the distribution system has undergone significant changes on the production and demand side. Due to alternating current (AC) and DC generators and load demands, it is not cost-effective to continue in the AC distribution system. Therefore, AC/DC hybrid distribution system planning is economical despite various demands and generations. On the other hand, uncertainty in load demand and output power of DGs cause the possible behavior of the distribution system. This behavior leads to risk in the distribution system. In this paper, the AC/DC distribution system planning is discussed by considering the risk. The planning problem in the matrix laboratory and general algebraic modeling system (MATLAB/GAMS) hybrid space has been formulated and solved. Using the K-means algorithm, the uncertainty related to renewable DG output power and load demand has been modeled. To verify the proposed method, it was implemented in a sample distribution system.