Power optimizer

About: Power optimizer is a research topic. Over the lifetime, 10525 publications have been published within this topic receiving 199245 citations.

Maximum power point tracker using fuzzy control for photovoltaic arrays

Abstract: The solar cell has an optimum operating point to be able to get the maximum power. To obtain the maximum power from a photovoltaic array, the photovoltaic power system usually requires a maximum power point tracking controller. This paper proposes a maximum power point tracking control of photovoltaic array using fuzzy control; the controller only uses the output power. Therefore, this control method is easy to implement to a real system. Moreover, this method can track maximum power point rapidly with fuzzy inference even if the optimum operating point changes. The usefulness of this control method is confirmed by experiments using step-down chopper with constant resistive rod. >

Modular multilevel converter for large-scale multistring photovoltaic energy conversion system

Abstract: This paper presents a new grid connected photovoltaic energy conversion system configuration for large scale power plants. The grid-tied converter is based on a modular multilevel converter using voltage source H-bridge cells. The proposed converter is capable of concentrating a multimegawatt PV plant with distributed string MPPT tracking capability, high power quality and increased efficiency compared to the classic two-level voltage source converters. The main challenge is to handle the inherent power unbalances which may occur, not only between the different cells of one phase of the converter, but also between the three phases. The control strategy to deal with these unbalances is analyzed in this paper. Simulation results for a downsized 7 level MMC composed of 18 H-bridge cells and PV strings are presented to validate the proposed topology and control method.

Distributed Stochastic Market Clearing With High-Penetration Wind Power

Abstract: Integrating renewable energy into the modern power grid requires risk-cognizant dispatch of resources to account for the stochastic availability of renewables. Toward this goal, day-ahead stochastic market clearing with high-penetration wind energy is pursued in this paper based on the DC optimal power flow (OPF). The objective is to minimize the social cost which consists of conventional generation costs, end-user disutility, as well as a risk measure of the system re-dispatching cost. Capitalizing on the conditional value-at-risk (CVaR), the novel model is able to mitigate the potentially high risk of the recourse actions to compensate wind forecast errors. The resulting convex optimization task is tackled via a distribution-free sample average based approximation to bypass the prohibitively complex high-dimensional integration. Furthermore, to cope with possibly large-scale dispatchable loads, a fast distributed solver is developed with guaranteed convergence using the alternating direction method of multipliers (ADMM). Numerical results tested on a modified benchmark system are reported to corroborate the merits of the novel framework and proposed approaches.

Grid-linked power supply

Abstract: A grid-linked power supply is described. An inverter, at least one distributed energy source to meet normal, non-peak power demand, a connection to a public utility grid to meet peak power demand requirements, and a converter for regulating delivery of power from the distributed energy source or the public utility grid are connected by bus lines. A topology for the grid-linked power supply has an inverter and a DC/DC converter that is connected to the distributed energy source. The inverter and converter are connected by bus lines, and a bias voltage is provided to select drawing power from the distributed energy source or the public utility grid.

A critical review of voltage and reactive power management of wind farms

Abstract: Wind generation is currently the major form of new renewable, generation in the world. The wind power is totally dependent on wind flow, due to randomness and uncertainty of wind flow, the wind power generation is quite fluctuating in nature and large scale wind farms may cause significant impact to the power system safety, quality and stability. The active power mainly depends upon the potential of the wind power produced and wind turbine generator design. The reactive power demand on the other hand depends upon conversion devices and recovered power quality fed to the grid. The wind farms which accesses to power grid cause fluctuations and reactive power redistribution and sometimes lead to voltage collapse. Similarly, the dynamic voltage stability is a major challenge faced by distribution network operators. The easy solution comes into picture is to install reactive power source devices with optimization of the existing assets to deliver enhanced reactive power to the grid. With solution to reliability, voltage regulation, reactive power requirements, grid integration problems, weak grid interconnection, off grid wind power generation and its integration to power grid, wind power penetration in distribution grid, wind power uncertainty, flicker and harmonics etc. The categorization of issue considered the goal of our work is the reactive power management of wind farm in most technical and economical way without compromising quality power system voltage, and considering the wind turbine technology for already commissioned wind farm, and change in WT technology in present scenario. More than 100 research publications on voltage and reactive power control of wind farms, extending from year 2003 to 2013 have been critically examined, classified and listed for quick reference.