Abstract

Abstract: Induction motors are the widely used machines in many industrial applications. But the induction motors results in high starting current, occurrence of common mode voltages, difficult to control etc. This work proposes controlling of a dual inverter fed induction motor with open end stator windings. The three level dual inverter received large attention due to its simplicity and it reduces the voltage rating of the semiconductor devices which further reduces cost of the system. This system is operated using an integrated control which includes maximum power point tracking and space vector pulse width modulation technique. A boosting converter with a high voltage gain is also used which requires no chemical storage elements such as batteries and make the system more effective. For tracking the maximum power Perturb and observe method is used. Space vector modulation is designed such that it eliminates the common mode voltages generated and has less distortions compared to the conventional methods. The modeling of dual inverter fed open end winding induction motor, conventional induction machine, PV system, MPPT algorithm, Dickson charge pump and switching of inverters using space vector modulation has been done and the output waveforms obtained are analyzed.

Keywords: Common mode voltage, Dickson charge pump, Open end winding induction motor, Space vector modulation.

Abstract: The static pollution-free Photovoltaic (PV) Cells are considered as one of the most important and promising type of renewable energy systems. Photovoltaic power generation is however possible only on a sunny day, and there is complete absence of power on a cloudy day .The suggested solution to this problem is a hybrid system. Hybrid systems such as Solar-Wind, Solar-Wind-Fuel Cell Hybrid systems etc are defined as energy systems combining two or more complementary power generation devices where the best features of each source is captured. A Novel Stand-Alone Photovoltaic –Synchronous Generator Hybrid system is proposed here, in which the Maximum Power Point of the PV generator is tracked, and is used to control the AVR of the Synchronous Generator .This AVR is now used to control the Voltage of the common coupling point of the Synchronous Generator and the PV Generator Thus the voltage of the PCC will be the voltage corresponding to the MPP. A Power control unit is incorporated to control the driving torque of the synchronous generator once the PV generator becomes unable to meet the requirements of the motor because of reduction of the solar irradiance and/or increase of the load.

Keywords: Photovoltaic Cell, Maximum power point tracking (MPPT), Automatic voltage regulator (AVR), Synchronous generator.

Abstract: The current source flyback micro inverter plays a vital role in PV applications. Presently central inverter system is replaced by micro inverter. Micro inverters are small inverters rated to handle the output of a single panel. Many converter topologies have been proposed for the AC-PV modules. Among those, the fly back inverter has been the center of attention because it satisfies the application requirements such as high voltage step-up ratio, galvanic isolation, low volume, high reliability, and provides high efficiency and relatively simple control. This paper proposes an efficient fly back inverter with mppt control. The center tapped transformer is replaced by a two winding transformer to decrease the current losses. Fly back inverter has three modes of operation. They are DCM (Discontinuous conduction mode), BCM(Boundary conduction mode) and CCM (Continuous conduction mode).By using mppt control we can avoid the problems of individual conduction modes. The performance of the proposed model is simulated in MATLAB/ Simulink environment.

Keywords: total harmonic distortion (THD), Transparent Conductive Oxides(TCO),Maximum power point tracking (MPPT)

Abstract:  As far as renewable energy is concerned solar photovoltaic means of energy production plays a major role. Since sun’s energy is available in abundant not completely its source is utilized by the photovoltaic cells. So, efficiency of the energy conversion scheme should be high. Hence a high-efficiency dc–dc converter is proposed for low-voltage photovoltaic sources. The proposed converter boosts up the DC voltage with high voltage gain and high efficiency. The proposed converter uses a transformer-less adjustable voltage quadrupler dc–dc converter with high-voltage transfer gain and reduced semiconductor voltage stress is proposed with an input-parallel output-series configuration for providing a much higher voltage gain without adopting an extreme large duty cycle.

Keywords: DC-DC converter, Photovoltaic (PV), Quadrupler.

Abstract-Converter system that does both dc–dc conversionand dc–ac conversion in a single stage is called a single-stage converter system (SSCS). The two stage power conversionwill be done in a single stage by this converter. The maindrawback of the two stage conversion system are complexity in control, low efficiency ,and large size. Maximum power point tracking also incorporated to track maximum power at different isolation .Incremental l conductance method is the method for maximum power point tracking used in the proposed system. The proposed system produce output voltage higher or lower than the input voltage .The proposed system has low switching loss, high gain, and compact in size. Coupled inductor is used to produce high gain . The proposed system produce output voltage of 230V.The simulation is done in MTLAB simulation results arepresented to validate the proposed idea.

Keywords-Single-stage, Gridconnected, Buck-boost, Inverter.

Abstract: The global energy crisis in near future due to the rapid depletion of conventional fossil fuel resources and a consistently diminishing costs of solar photovoltaic (PV)modules, motivate towards an effective utilization of solar PV technology. In order to optimize the solar photovoltaic (PV) generated power using a maximum power point tracking (MPPT) technique, a DC-DC conversion stage is usually required in solar PV fed water pumping which is driven by a brushless DC (BLDC) motor. This power conversion stage leads to an increased cost, size, complexity and reduced efficiency. Here addresses a single stage solar PV energy conversion system feeding a BLDC motor-pump, which eliminates the DC-DC conversion stage. In addition, it constitutes the attractive merits of conventional topology , such as the elimination of BLDC motor phase current sensing and soft starting. The suitability of proposed system is validated through its performance and evaluation using MATLAB/Simulink based simulated results.

Key words: MPPT, Solar PV array, BLDC motor, Water pump, VSI, Soft starting, Speed control