Binu Ben Jose Dharmaian Retnam

Bio: Binu Ben Jose Dharmaian Retnam is an academic researcher from National Institute of Technology, Tiruchirappalli. The author has contributed to research in topics: Power optimizer & Maximum power point tracking. The author has an hindex of 1, co-authored 2 publications receiving 20 citations.

Hybrid power electronic controller for combined operation of constant power and maximum power point tracking for single-phase grid-tied photovoltaic systems

Abstract: This study presents a hybrid technique that offers constant power operation for single-phase grid-tied photovoltaic (PV) systems while performing maximum power point tracking function. A boost converter and a line commutated inverter (LCI) have been used for interfacing PV array with utility grid. Fixed firing angle of the LCI keeps the dc-link voltage constant and the boost converter extracts maximum power from the solar PV array by simply adjusting the duty ratio of the boost converter. A low-capacity battery bank connected at the dc link is used to deliver constant power to grid. Harmonic filter is eliminated as the system inherently delivers quality supply with reduced current harmonics. PIC microcontrollers have been programmed for generating pulses to the inverter and the boost converter. The system has been simulated in MATLAB/Simulink and the simulation results are presented. The parameters of a PV panel rated for 100 W, 21.5 V and 6.83 A have been used for the simulation. Experiments have been conducted on the 21.5 V, 6.83 A PV panel for obtaining a constant power of 80 W with varying irradiation and the results correlate with the simulation study.

Power Electronic Interface with Maximum Power Point Tracking Using Line-commutated Inverter for Grid-connected Permanent Magnet Synchronous Generator

Abstract: —This article presents a simple grid interactive system that extracts maximum power from a wind-driven permanent magnet synchronous generator using an integrated cascade boost converter and a three-phase line-commutated inverter. The firing angle of the line-commutated inverter is held constant at an appropriate value that provides a constant DC-link voltage, and only DC-link current is sensed for maximum power point tracking. For wide wind variation, maximum power from the permanent magnet synchronous generator is achieved using a simple load current (DC-link current) perturb and observe maximum power point tracking technique. This is obtained by varying the duty ratio of the integrated cascade boost converter with an adaptive incremental step that varies the load on the permanent magnet synchronous generator in accordance with changing wind. Experiments have been conducted on a 3-phase, 750-W, 500-rpm laboratory size permanent magnet synchronous generator. The operation and analysis of the propo...

A comprehensive overview of maximum power extraction methods for PV systems

Abstract: The power generated by photovoltaic (PV) system depends on environment irradiance and temperature parameters. Hence, PV panels have nonlinear characteristics. In uniform condition, there is only one maxima point called maximum power point (MPP) where the PV system operates in maximum efficiency. However, in non-uniform condition such as partial shading effects, the PV system presents multiple maxima points on the correspondence P-V curve due to bypass diodes which makes more difficult to estimate global MPP. That is why it makes maximum power point tracking (MPPT) more important for PV systems to operate in maximum efficiency. In the literature, various types of MPPT technique and alternative solutions are used to detect true global MPP point among the other local MPPs. In addition, different PV array topologies, architectures and configurations are proposed to remove local maxima on the P-V curve. In this paper, most popular and used MPPT techniques, PV array configurations, system architectures and circuit topologies are discussed. In this context, this paper provides an overview of the operating principles discusses advantages and disadvantages and makes a general comparison between different solutions of each method.

Performance evaluation of an asymmetrical reduced switched multi-level inverter for a grid-connected PV system

Abstract: This study presents the performance analysis of a new asymmetrical multi-level inverter using reduced number of switches for a single-phase grid-tied photovoltaic (PV) system. The solar PV panels of unequal power rating are connected in an appropriate manner to obtain the DC link voltages of suitable ratio for an asymmetrical cascaded multi-level inverter. The PV power, voltages as well as the current injected into the grid have been controlled using the separate maximum power point tracking, voltage controllers and a current controlled technique to achieve the maximum power with sinusoidal current with a unity power factor. The variations of DC link voltages, inverter voltage and injected grid current are simulated and are experimentally verified under the variable irradiation as well as grid voltage fluctuation. The simulation and the corresponding hardware results of the proposed reduced switch asymmetrical seven-level inverter for a low-power residential grid-tied PV system is also presented.

Simple brushless DC motor drive for solar photovoltaic array fed water pumping system

Abstract: This study deals with a buck–boost converter controlled solar photovoltaic (SPV) array fed water pumping in order to achieve the maximum efficiency of an SPV array and the soft starting of a permanent magnet brushless DC (BLDC) motor. The current sensors normally used for speed control of BLDC motor are completely eliminated. The speed of BLDC motor is controlled through the variable DC-link voltage of a voltage-source inverter (VSI). The VSI is operated by fundamental frequency switching, avoiding the losses due to high-frequency switching, in order to enhance the efficiency of the proposed system. The dynamic and steady-state behaviours of the proposed system are demonstrated under rapid variations in atmospheric conditions. An experimental validation is also made to validate the design and simulated results under real circumstances on a developed prototype.

On the Effects of Solar Panels on Distribution Transformers

Abstract: Energy policies worldwide are mandating large-scale integration of solar panel (SP) generators with inverters on distribution systems. This causes several SPs to be connected to a distribution transformer. The SP and its interfacing inverter alter the performance characteristics of the transformer. In addition, when new sources and loads are connected to a distribution system, from an asset-management perspective, it is imperative to understand and quantify their effect on distribution system components. This paper presents a two-step study on the effects of SP on distribution transformers via simulation and experiments. In step one, the simulation work quantifies the amount of harmonic distortion caused by SP and associated inverters in distribution transformers considering solar farms and rooftop residential installations. The simulation work uses network topology, load, and generation data of a Canadian utility. Various inverter technologies, output powers, carrier signal frequencies, filtering techniques, numbers of active inverters, and transformer configurations are studied. In step two, level of harmonic distortion observed in simulation is created in a laboratory environment using a commercial inverter for SP applications. A three-phase dry-type transformer is tested to observe the effect of higher harmonic distortion on core and winding temperatures of the transformer. Experimental results conclude that under the worst case loading scenario (i.e., full load with active power flow reversed), the transformer lifetime expectancy is anticipated to decrease by 8.3%.