scholarly journals A Scalable Control Strategy for CHB Converters in Photovoltaic Applications

Energies ◽  
2021 ◽  
Vol 15 (1) ◽  
pp. 208
Author(s):  
Álvaro Pérez Mayo ◽  
Ainhoa Galarza ◽  
Asier López Barriuso ◽  
Javier Vadillo

Renewable energy sources are becoming more relevant in recent decades in power generation, leading to investment in developing efficient systems. Specifically, in photovoltaic energy, modular converters are attracting interest since their characteristics enable them to work at high voltage and optimize the generated energy. However, the control strategies found the literature limit the scalability potential of modular converters. The main aim of this paper is to propose a scalable control strategy for a grid-tied CHB (Cascaded H-Bridge) converter for large-scale photovoltaic power plants. The control proposed is able to take full advantage of converter scalability and modularity, being based on the parameters needed for bipolar sinusoidal PWM (Pulse Width Modulation), and thus reducing the calculus required and simplifying its implementation. Power imbalances are overcome including the zero-sequence vector injection to allow power exchange between phases. Furthermore, the parameter used for power factor control has been discretized and discretization time analysis shows that the control strategy is stable and does not require a high-speed communication channel. For validation purposes, simulations are conducted on a downsized 12 H-bridge model.

2020 ◽  
Author(s):  
Anubhav Jain ◽  
Jayachandra N. Sakamuri ◽  
Nicolaos A. Cutululis

Abstract. Large-scale integration of renewable energy sources with power-electronic converters is pushing the power system closer to its dynamic stability limit. This has increased the risk of wide-area blackouts. Thus, the changing generation profile in the power system necessitates the use of alternate sources of energy such as wind power plants, to provide blackstart services in the future. This however, requires grid-forming and not the traditionally prevalent grid-following wind turbines. In this paper, four different grid-forming control strategies have been implemented in an HVDC-connected wind farm. A simulation study has been carried out to test the different control schemes for the different stages of energization of onshore load by the wind farm. Their transient behaviour during transformer inrush, converter pre-charge and de-blocking, and onshore block-load pickup, has been compared to demonstrate the blackstart capabilities of grid-forming wind power plants for early participation in power system restoration.


2020 ◽  
Vol 5 (4) ◽  
pp. 1297-1313 ◽  
Author(s):  
Anubhav Jain ◽  
Jayachandra N. Sakamuri ◽  
Nicolaos A. Cutululis

Abstract. Large-scale integration of renewable energy sources with power-electronic converters is pushing the power system closer to its dynamic stability limit. This has increased the risk of wide-area blackouts. Thus, the changing generation profile in the power system necessitates the use of alternate sources of energy such as wind power plants, to provide black-start services in the future. However, this requires grid-forming and not the traditionally prevalent grid-following wind turbines. This paper introduces the general working principle of grid-forming control and examines four of such control schemes. To compare their performance, a simulation study has been carried out for the different stages of energization of onshore load by a high-voltage direct-current (HVDC)-connected wind power plant. Their transient behaviour during transformer inrush, converter pre-charging and de-blocking, and onshore block-load pickup has been compared and analysed qualitatively to highlight the advantages and disadvantages of each control strategy.


Energies ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 3296
Author(s):  
Carlos García-Santacruz ◽  
Luis Galván ◽  
Juan M. Carrasco ◽  
Eduardo Galván

Energy storage systems are expected to play a fundamental part in the integration of increasing renewable energy sources into the electric system. They are already used in power plants for different purposes, such as absorbing the effect of intermittent energy sources or providing ancillary services. For this reason, it is imperative to research managing and sizing methods that make power plants with storage viable and profitable projects. In this paper, a managing method is presented, where particle swarm optimisation is used to reach maximum profits. This method is compared to expert systems, proving that the former achieves better results, while respecting similar rules. The paper further presents a sizing method which uses the previous one to make the power plant as profitable as possible. Finally, both methods are tested through simulations to show their potential.


2012 ◽  
Vol 512-515 ◽  
pp. 788-793
Author(s):  
Xiao Hua Zhou ◽  
Ming Qiang Wang ◽  
Wei Wei Zou

Traditional decoupling control strategy of doubly-fed induction generator (DFIG) wind turbine makes little contribution to system inertia and do not participate in the system frequency control, the synchronization of large-scale wind power requires wind turbine have the ability to participate in the regulation of power system frequency. This paper adds a frequency control segment to traditional DFIG wind turbine and considers the doubly-fed wind turbine operating on the state of the super-synchronous speed, by analysis the effect of inertia and proportional control strategies, a fuzzy control strategy which combines the advantages of the former two control strategies is proposed, simulation results show that this control strategy can more effectively improve the system frequency response.


2020 ◽  
Author(s):  
Ana Fernández-Guillamón ◽  
Emilio Gómez-Lázaro ◽  
Eduard Muljadi ◽  
Ángel Molina-Garcia

Over recent decades, the penetration of renewable energy sources (RES), especially photovoltaic and wind power plants, has been promoted in most countries. However, as these both alternative sources have power electronics at the grid interface (inverters), they are electrically decoupled from the grid. Subsequently, stability and reliability of power systems are compromised. Inertia in power systems has been traditionally determined by considering all the rotating masses directly connected to the grid. Thus, as the penetration of renewable units increases, the inertia of the power system decreases due to the reduction of directly connected rotating machines. As a consequence, power systems require a new set of strategies to include these renewable sources. In fact, ‘hidden inertia,’ ‘synthetic inertia’ and ‘virtual inertia’ are terms currently used to represent an artificial inertia created by inverter control strategies of such renewable sources. This chapter reviews the inertia concept and proposes a method to estimate the rotational inertia in different parts of the world. In addition, an extensive discussion on wind and photovoltaic power plants and their contribution to inertia and power system stability is presented.


2020 ◽  
Author(s):  
Paulo Andrade Souza ◽  
Renan R. dos Santos ◽  
Manoelito C. N. Filho ◽  
Daniel Barbosa ◽  
Luciano Sales Barros

Due to the increasing penetration of Renewable Energy Sources (RES) such as wind energy in electrical grids, Wind Energy Conversion Systems (WECS) participation in primary control is becoming required including the Doubly Fed Induction Generator (DFIG)-based WECS. High integration of large scale DFIG-based WECS brings new challenges to their primary control support, and more strongly due to the wind condition and grid parameter uncertainties. One of the most used types of control strategy for DFIG-based WECS primary support is the synthetic inertia, however, robustness of these techniques have not been tested. In this work three synthetic inertia control strategies will be tested under different operating conditions of wind speed, frequency and voltage sag. For testing the DFIG-based WECS, it was modeled on ATP including its control systems and the results quantified the controllers robustness on the tested controllers with respect to transient frequency behavior.


IJOSTHE ◽  
2020 ◽  
Vol 7 (1) ◽  
pp. 5
Author(s):  
Ankeeta . ◽  
Vasant Acharya

Power generation through the renewable energy sources has become more viable and economical than the fossil fuel based power plants. By integrating small scale distributed energy resources, microgrids are being introduced as an alternative approach in generating electrical power at distribution voltage level. The power electronic interface provides the necessary flexibility, security and reliability of operation between micro-sources and the distribution system. The presence of non-linear and the unbalanced loads in the distribution system causes power quality issues in the Microgrid system. This paper explores and reviews different control strategies developed in the literature for the power quality enhancement in microgrids.


2018 ◽  
Vol 245 ◽  
pp. 15005 ◽  
Author(s):  
Vyacheslav Shestakov ◽  
Olga Novikova ◽  
Artem Melnichenko ◽  
Anastasia Luchnikova

In this article we consider the potential possibility of using renewable energy sources for the construction of transport infrastructure facilities of the Federal importance. We analyzed major promising projects for the construction of roads and bridges for the period until 2030 year, considered a step-by-step scheme for energy supply of a large facility, using the example of the Kerch bridge, and made an analysis of the potential usage of hybrid power plants based on renewable energy sources for the implementation of projects. We developed methodological approaches to the implementation of large-scale projects that would allow one to take into account not only economic efficiency, but all the positive effects that can be achieved from the project.


Green ◽  
2014 ◽  
Vol 4 (1-6) ◽  
Author(s):  
Arndt Neuhaus ◽  
Frank-Detlef Drake ◽  
Gunnar Hoffmann ◽  
Friedrich Schulte

AbstractThe transition to a sustainable electricity supply from renewable energy sources (RES) imposes major technical and economic challenges upon market players and the legislator. In particular the rapid growth of volatile wind power and photovoltaic generation requires a high level of flexibility of the entire electricity system, therefore major investments in infrastructures are needed to maintain system stability. This raises the important question about the role that central large-scale energy storage and/or small-scale distributed storage (“energy storage at home”) are going to play in the energy transition. Economic analyses show that the importance of energy storage is going to be rather limited in the medium term. Especially competing options like intelligent grid extension and flexible operation of power plants are expected to remain favourable. Nonetheless additional storage capacities are required if the share of RES substantially exceeds 50% in the long term. Due to the fundamental significance of energy storages, R&D considers a broad variety of types each suitable for a specific class of application.


Author(s):  
Hans Mu¨ller-Steinhagen

On October 30th 2009, a major industrial consortium initiated the so-called DESERTEC project which aims at providing by 2050 15% of the European electricity from renewable energy sources in North Africa, while at the same time securing energy, water, income and employment for this region. In the heart of this concept are solar thermal power plants which can provide affordable, reliable and dispatchable electricity. While this technology has been known for about 100 years, new developments and market introduction programs have recently triggered world-wide activities leading to the present project pipeline of 8.5 GW and 42 billion Euro. To become competitive with mid-load electricity from conventional power plants within the next 10–15 years, mass production of components, increased plant size and planning/operating experience will be accompanied by technological innovations which are presently in the development or even demonstration stage. The scale of construction, the high temperatures and the naturally transient operation provide formidable challenges for academic and industrial R&D. Experimental and theoretical research involving all mechanisms of heat transfer and fluid flow is required together with large-scale demonstration to resolve the combined challenges of performance and cost.


Sign in / Sign up

Export Citation Format

Share Document