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Grid frequency regulation is essential for a reliable power grid. Whilst in distributed energy sources, (DERs) power fluctuations arise from the imbalance of frequency. There are multiple conventional and recent advanced frequency regulation techniques to dissolve this issue. The existing techniques using conventional controllers in microgrid control are well suited for voltage regulation, but the frequency cannot be adequately controlled using conventional and linear controllers. Most of the advanced control methods use algorithms to manage the grid frequency stability. This review comprehensively discusses the advanced control techniques for frequency regulation in micro-grids namely model predictive control, adaptive control, sliding mode control, h-infinity control, back-stepping control, (Disturbance estimation technique) kalman state estimator-based strategies, and intelligent control methods. Each control method is briefly explained along with recent advancements and corresponding governing equations. At glace, these control techniques are comparatively studied by elaborating future requirements.

Approximate computing is widely used in a large number of error-tolerant applications. Multiplication is an integral arithmetic operation for many of these applications. In this paper we discuss 8 bit multiplier designs designed using approximate 4:2 compressors and encoded sum of partial products, and later introduce an approximate full adder to compute the sum of partial products in less significant bit positions. We use these techniques to systematically trade off accuracy for improvements in area, power and more significantly delay. These multipliers were designed using Verilog and synthesized using Cadence Design Suite with the help of a 45nm standard cell library. The physical designs of exact, existing and proposed multipliers were also performed using the open source RTL to GDS flow tool Q-flow. This is done to highlight the importance and reliability of open source tools in the VLSI physical design process when compared to paid software which may not be accessible to everyone.

The transition of the energy sector from using conventional sources to sustainable sources paves the way for the exploration of various new energy sources. Since the past classifications are often based on subjective criteria such as whether an energy source is either renewable or fossil fuel. This causes to lack of representation of emerging energy sources such as vibration, acoustic and human heat, etc. Also, the by-products of energy systems after useful conversion such as discharged heat from turbine and exhaust flue gases are never considered as a source but rather called energy efficiencies feature of the system. The current classification uses facts-based objective criteria to classify the energy sources as renewable, reserve, and capture energy sources. The terms and definitions to annex energy sources under a particular category are theoretically justified. Another important aspect that is, to meet sustainable development goals the need to choose low carbon emissions as the primary criteria for promoting energy source utilization and economic policymaking is insisted.

A high yielding white seeded sesame culture VS 07 023 was developed at Regional Research Station, Vridhachalam and released as VRI 3 during 2017. It is a cross derivative of SVPR 1 and TKG 87. The culture was evaluated during rabi and summer seasons. The culture VS 07 023 has registered an overall grain yield of 995 kg/ha which was 22.74 and 17.33 per cent yield increase over the check SVPR 1 (811kg/ha) and TMV (SV) 7 (848 kg/ha), respectively over 95 locations during rabi season. Similarly, the culture VS 07 023 has registered remarkably a higher mean seed yield of 1055 kg/ha against the check SVPR 1 (862 kg/ha) and TMV (SV) 7 (928kg/ha). The per cent increase in the mean seed yield over the check was 22.49 (SVPR 1) and 13.77 per cent (TMV (SV) 7). The culture is moderately resistant to Macrophomina root rot disease. The culture VS 07 023 is white seeded containing 50 per cent oil content and exhibited a profuse branching suitable for rabi and summer irrigated conditions. In view of stable performance of sesame culture VS 07 023, it was released as a new sesame variety VRI 3 during 2017 by Tamil Nadu Agricultural University, Coimbatore for cultivation in major sesame growing districts of Tamil Nadu during rabi and the summer irrigated conditions.

Different intermediate steps exist between solar energy as input and hydrogen as output. Most of the findings in this domain revolved around water electrolysis as an intermediate step to produce hydrogen. Therefore, the discussion in the work is intended to discuss water-splitting-based hydrogen production through electrolysis. The electrolysis process requires continuous electrical input. Installed solar PV is inevitably supposed to be under prolonged solar irradiance. The prolonged solar incidence causes the panel to get heated, leading to lower overall performance. Thermoelectric Generators (TEGs) convert the waste heat into additional electrical energy apart from the panel. In the experimentation of the work, the effect of temperature gradient is explored. During the implementation of PV-TEG, TEG electrical output can be improved with the help of auxiliary heat dissipators. This study includes graphite as a heat dissipator and a Hofmann voltameter for hydrogen production. Under 800 W/m2 of solar irradiation, the maximum hydrogen yield is obtained when PV-TEG (with graphite sheet) is connected to the Hofmann voltameter. The yield ranges from 0.132 bar/sec to 0.137 bar/sec. [ABSTRACT FROM AUTHOR]