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This paper presents a non-isolated single switch converter with high voltage gain. Its circuit topology is combined with coupled-inductor, clamp circuit, and voltage lift capacitor techniques. The proposed converter has several advantages: First, the circuit is controlled by only single pulse width modulation (PWM) for the power switch, which keeps the circuit simple. Secondly, the proposed converter is used as a clamping circuit,which let the energy of the leakage inductance can be circulated to the capacitor, so that the voltage spike on the active switch can be suppressed, and improves efficiency. This paper will introduce the principle of action, theoretical analysis, and experimental waveform in order. Finally, in the case of input voltage of 48 V, output voltage of 400 V, and output power of 1 kW, the performance of the proposed converter is verified. As a result, the maximum efficiency is up to 96.5% and full load efficiency is 92.3%. [ABSTRACT FROM AUTHOR]

This paper emphasizes on proposing a dynamic voltage restorer–based superconducting magnetic storage devices have utilized to power quality issues. Dynamic voltage restorer can be used for different topologies of the inverter. The conventional topology of dynamic voltage restorer possessing voltage source inverter or Z-source inverter is modified into a switched coupled inductor inverter which has the clear edge in power transfer over the former. The versatility of the controller is enhanced by this work by deploying a fuzzy combine discrete wavelet transforms. The proposed system in this paper, switched coupled inductor inverter–based dynamic voltage restorer-superconducting magnetic storage devices on mitigating the interruption, harmonics and voltage sag/swell. The operating of switched coupled inductor inverter has buck/boost function capability and reduced number of passive components. Due to digitalization, higher utilization factor and reduced harmonic content, controller of fuzzy logic–space vector pulse width modulation techniques with filter application of discrete wavelet transform is used to operate of switched coupled inductor inverter. The hysteresis controller is used to perform the superconducting magnetic storage devices device, has the ability in the storage of real power with high energy density and protects the consumer from grid fluctuation. To detect the power quality disturbances quickly response and improve the compensation capability of dynamic voltage restorer-superconducting magnetic storage devices. The whole of the suggested system is simulated in MATLAB/Simulink and realized as a prototype whose control pulses are duly generated and fed by dSPACE 1104 controller. [ABSTRACT FROM AUTHOR]

This paper presents a non-isolated single switch converter with high voltage gain. Its circuit topology is combined with coupled-inductor, clamp circuit, and voltage lift capacitor techniques. The proposed converter has several advantages: First, the circuit is controlled by only single pulse width modulation (PWM) for the power switch, which keeps the circuit simple. Secondly, the proposed converter is used as a clamping circuit,which let the energy of the leakage inductance can be circulated to the capacitor, so that the voltage spike on the active switch can be suppressed, and improves efficiency. This paper will introduce the principle of action, theoretical analysis, and experimental waveform in order. Finally, in the case of input voltage of 48 V, output voltage of 400 V, and output power of 1 kW, the performance of the proposed converter is verified. As a result, the maximum efficiency is up to 96.5% and full load efficiency is 92.3%. [ABSTRACT FROM AUTHOR]

The common dual-pulse-width-modulation converter adopts the independent method to control the rectifier and inverter, which has the defects including direct current voltage fluctuation, slow system response and so on. A coordinate strategy of dual-pulse-width modulation based on direct power control with load power feed-forward is proposed in this paper. The fixed switching frequency method with space vector pulse width modulation is provided to overcome the instability of power devices, caused by the hysteresis comparators in the conventional direct power control. With the analysis on the dynamic performance of load power feed-forward coordination, the principle of load power feed-forward is introduced to control the dual-pulse-width-modulation converter. According to the state variable of the alternating current motor, the load power is estimated to construct the feed-forward channel. The experimental results show that the proposed coordinate control method has rapid response, direct current bus voltage fluctuation minimization, lower capacity and unit power factor. [ABSTRACT FROM AUTHOR]

This article presents a reliable and efficient photovoltaic sliding mode voltage-controlled maximum power point tracking DC-DC converter–active power filter integration system to supply real power to grid. This integrated active power filter system performs power quality enhancement features to compensate current harmonics to make distortion-free grid supply current and reactive power employing nonlinear loads. The proposed proportional–integral–derivative–based sliding mode controller is designed with fixed-frequency pulse-width modulation based on equivalent control approach. The main objective of this paper is to design a photovoltaic system with a new sliding surface to force the photovoltaic voltage to follow the reference maximum power point voltage with the alleviation of slow transient response and disadvantages of chattering effects of variable-frequency hysteresis modulation sliding mode controller–maximum power point tracking. The perturbations caused by the uncertainties in climatic conditions and converter output bulk oscillations during grid integration are also mitigated. The features of the proposed photovoltaic–active power filter integration system are confirmed at different operating conditions through PSIM simulation software, and its performance is also compared with a conventional variable-frequency sliding mode-controlled maximum power point tracking. The obtained simulation and experimental results give good dynamic response under various operating conditions of environmental and local load conditions. [ABSTRACT FROM AUTHOR]

Energy ripples are among the common problems in renewable energies as a result of using less efficient strategies. In this work, a new technique is suggested to control a doubly-fed induction generator (DFIG) using the pulse width modulation (PWM). The new technique is based on the combination of neural networks and fractional-order control to minimize the reactive and active power ripples of the DFIG-based variable speed dual-rotor wind turbine system. The suggested fractional-order neural control (FONC) with the PWM is a simple, robust and a high-performance strategy. Simulation is performed using Matlab software to validate the effectiveness of the designed control of 1.5 MW DFIG and the obtained results are compared with the traditional direct power control (DPC) in different working conditions. In addition, the comparison between the suggested control and the DPC is performed in the cases of changing or not changing the device parameters in terms of ripple ratio, dynamic response, steady-state error, current quality, and overshoot of active and reactive power of the DFIG. As compared to the DPC, the proposed FONC technique improves the active and reactive power ripples by 65.71% and 84.74%, respectively. Also, improves the overshoot of the active and reactive power by 71.33% and 91.72%, respectively. The simulation results demonstrate the high performance and robustness of the FONC technique for the parametric variations of the DFIG-based variable speed dual-rotor wind turbine system compared to the DPC control. [ABSTRACT FROM AUTHOR]