Predicting Harmonic Distortion of Multiple Converters in a Power System

Various uncertainties arise in the operation and management of power systems containing Renewable Energy Sources (RES) that affect the systems power quality. These uncertainties may arise due to system parameter changes or design parameter choice. In this work, the impact of uncertainties on the prediction of harmonics in a power system containing multiple Voltage Source Converters (VSCs) is investigated. The study focuses on the prediction of harmonic distortion level in multiple VSCs when some system or design parameters are only known within certain constraints. The Univariate Dimension Reduction (UDR) method was utilized in this study as an efficient predictive tool for the level of harmonic distortion of the VSCs measured at the Point of Common Coupling (PCC) to the grid. Two case studies were considered and the UDR technique was also experimentally validated. The obtained results were compared with that of the Monte Carlo Simulation (MCS) results.

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Operational Planning and Bidding for District Heating Systems with Uncertain Renewable Energy Production

Energies ◽

10.3390/en11123310 ◽

2018 ◽

Vol 11 (12) ◽

pp. 3310 ◽

Cited By ~ 4

Author(s):

Ignacio Blanco ◽

Daniela Guericke ◽

Anders Andersen ◽

Henrik Madsen

Keyword(s):

Renewable Energy ◽

Power Systems ◽

Power System ◽

Electricity Markets ◽

Electricity Market ◽

Renewable Energy Sources ◽

District Heating ◽

Operational Planning ◽

Solution Approach ◽

The Impact

In countries with an extended use of district heating (DH), the integrated operation of DH and power systems can increase the flexibility of the power system, achieving a higher integration of renewable energy sources (RES). DH operators can not only provide flexibility to the power system by acting on the electricity market, but also profit from the situation to lower the overall system cost. However, the operational planning and bidding includes several uncertain components at the time of planning: electricity prices as well as heat and power production from RES. In this publication, we propose a planning method based on stochastic programming that supports DH operators by scheduling the production and creating bids for the day-ahead and balancing electricity markets. We apply our solution approach to a real case study in Denmark and perform an extensive analysis of the production and trading behavior of the DH system. The analysis provides insights on system costs, how DH system can provide regulating power, and the impact of RES on the planning.

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Harmonics Mitigation Based on the Minimization of Non-Linearity Current in a Power System

Designs ◽

10.3390/designs3020029 ◽

2019 ◽

Vol 3 (2) ◽

pp. 29 ◽

Cited By ~ 1

Author(s):

Mohammed S. Almutairi ◽

Sillas Hadjiloucas

Keyword(s):

Power Systems ◽

Power System ◽

Harmonic Distortion ◽

Nonlinear Loads ◽

Loading Constraints ◽

Harmonic Pollution ◽

Point Of Common Coupling ◽

Ieee Standards ◽

Total Voltage ◽

Practical Constraints

Harmonic issues in power systems are becoming an important topic for industrial customers and power suppliers alike due to their adverse effects in both consumer appliances as well as for utility suppliers. Consumers should seek to reduce harmonic pollution, regardless of voltage or current distortion already present in the network. This article suggests a new method for suppressing distortions by using the non-linearity current index (NLCI) to determine the shunt single-tuned passive filter (STPF) compensator value in non-sinusoidal power systems, with the objective of maintaining the power factor within desired limits. The objective of the proposed method is to minimize the nonlinear current of customer’s loads in the power system at the point of common coupling (PCC). Moreover, the proposed design takes into consideration other practical constraints for the total voltage and individual harmonic distortion limits, ensuring compliance with (Institute of Electrical and Electronics Engineers) IEEE 519-2014 guidelines, maintaining distortions at an acceptable level while also abiding by the capacitor loading constraints established in IEEE 18-2012. The performance of the optimally designed compensator is assessed using well documented IEEE standards based on numerical examples of nonlinear loads taken from previous publications.

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A Comprehensive Survey on the Impact of Renewable Energy Sources in Power System Operation and Control

10.21203/rs.3.rs-338842/v1 ◽

2021 ◽

Author(s):

Vinay Kumar Tatikayala ◽

Shishir Dixit

Keyword(s):

Artificial Intelligence ◽

Renewable Energy ◽

Power Systems ◽

Power System ◽

Renewable Energy Sources ◽

Energy Sources ◽

System Operation ◽

System Parameters ◽

And Control ◽

The Impact

Abstract The concern for huge increasing electricity demand, fossil fuel depletion, developed infrastructure reliability, carbon footprint reduction insisted the power utility companies to uptake RES (Renewable Energy Sources). The improved adoption of RES like wind energy and solar energy into the prevailing transmission and distribution networks led to several problems. These problems could be rectified by optimizing the power system parameters like frequency response, inertia, stability, battery usage, efficiency and power loss. This review hence provide a comprehensive analysis on the impact of renewable energy sources like wind and solar energy on power system operation and control in accordance with the major findings of the existing works. This review highlights the difficulties in the installation of solar and wind power with adoptable solutions. The challenges of power systems regarding the encoding of non-linearized function could be rectified by AI (Artificial Intelligence). The paper also insists the importance of artificial intelligence algorithm in the optimization of power system parameters. Artificial intelligence methods is useful for resolving various issues in power systems such as control, scheduling, forecasting etc. Few artificial algorithms such as Atom search optimization, Particle swarm optimization, Salp swarm optimization were investigated in this review for improving the performance of the power system. In spite of optimization analysis, the paper investigate various storage system types for improving the power system in accordance with cost, application and operation characteristics. Proper understanding of these systems is necessary for the future designing and hence through revision of state of art characteristics has been performed in this paper.

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Harmonics Mitigation of a Solar PV-Fuel Cell Based Microgrid System using a Shunt Active Power Filter

ECTI Transactions on Electrical Engineering, Electronics, and Communications ◽

10.37936/ecti-eec.2021192.222556 ◽

2021 ◽

Vol 19 (2) ◽

pp. 127-135

Author(s):

Sarita Samal ◽

Prasanta Kumar Barik ◽

Prakash Kumar Hota

Keyword(s):

Fuel Cell ◽

Renewable Energy Sources ◽

Harmonic Distortion ◽

Active Power Filter ◽

Active Power ◽

Voltage Source ◽

Solar Pv ◽

Shunt Active Power Filter ◽

Power Filter ◽

The Impact

The increased penetration of distributed energy resources is inspiring the entire design of conventional electrical power systems. A Microgrid (MG) includes distributed generation, loads, energy storage, and a control system capable of operating in grid-connected mode and/or island mode. The power quality (PQ) issue is one of the main technical challenges in an MG power system. To improve PQ, it is necessary to analyze the harmonic distortion of the system. Moreover, harmonic distortion in MG networks has significantly reduced PQ, affecting the stability of the system. The shunt active power filter (SAPF) has been extensively used to diminish the current harmonics and verified as being the best solution. Hence, in this paper, the impact of PQ issues in an adopted standalone MG system (comprising solar and fuel cell based renewable energy sources) is investigated in the presence of SAPF. The SAPF is realized using a conventional synchronous reference frame (SRF) technique for current generation with a pulse-width modulation voltage source inverter technique to generate pulses for the inverter along with a PI controller to regulate the DC-link capacitor voltage. The proposed model is developed in MATLAB/SIMULINK and the results validate the superiority of the proposed technique over others in terms of harmonic elimination.

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Sensitivity Analysis of the Impact of the Sub- Hourly Stochastic Unit Commitment on Power System Dynamics

Energies ◽

10.3390/en13061468 ◽

2020 ◽

Vol 13 (6) ◽

pp. 1468

Author(s):

Taulant Kërçi ◽

Juan S. Giraldo ◽

Federico Milano

Keyword(s):

Power Systems ◽

Power System ◽

System Dynamics ◽

New England ◽

Unit Commitment ◽

Frequency Control ◽

Renewable Energy Sources ◽

Power System Dynamics ◽

Stochastic Unit Commitment ◽

The Impact

Subhourly modeling of power systems and the use of the stochastic optimization are two relevant solutions proposed in the literature to address the integration of stochastic renewable energy sources. With this aim, this paper deals with the effect of different formulations of the subhourly stochastic unit commitment (SUC) problem on power system dynamics. Different SUC models are presented and embedded into time domain simulations (TDS) through a cosimulation platform. The objective of the paper is to study the combined impact of different frequency control/machine parameters and different SUC formulations on the long-term dynamic behaviour of power systems. The analysis is based on extensive Monte Carlo TDS (MC-TDS) and a variety of scenarios based on the New England 39-bus system.

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Comparison of Virtual Synchronous Generator Strategies for Control of Distributed Energy Sources and Power System Stability Improvement

10.48011/sbse.v1i1.2482 ◽

2021 ◽

Author(s):

Guilherme Penha da Silva Júnior ◽

Thiago Figueiredo do Nascimento ◽

Luciano Sales Barros

Keyword(s):

Power Systems ◽

Power System ◽

Renewable Energy Sources ◽

Synchronous Generator ◽

System Stability ◽

Control Mode ◽

Voltage Source ◽

Energy Sources ◽

And Performance ◽

Virtual Synchronous Generator

The high integration of distributed generation (DG) system based on renewable energy sources (RES) in the power system requires changes regarding the control mode of these sources with some urgency. Such changes seek to maintain the stability of the power systems. Thus, there is a demand for using control techniques on DGs/RESs that can mitigate the disturbances caused by low inertia and the lack of control over the dispatched powers. As a solution, one can use virtual synchronous generator (VSG) techniques making the voltage source inverter (VSI) control behave similarly to the traditional synchronous generator (SG). This paper presents a literature review and performance tests for the main VSG topologies used in DGs/RESs: ISE, VSYNC, VISMA and Synchronverter. The implementation of VSG in the DGs/RESs has made possible increase inertia in the grid and, additionally regulate the active and reactive powers separately and bidirectionally. So, it has been possible to meet power system requirements; being able to operation both grid-connected or island-mode, which is ideal for microgrids. The results obtained confirm the literature reports. It was observed that the Synchronverter topology presented advantages over the other VSG topologies.

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A Proposed Harmonic Monitoring System for Large Power Users Considering Harmonic Limits

Energies ◽

10.3390/en13174507 ◽

2020 ◽

Vol 13 (17) ◽

pp. 4507

Author(s):

Rosalia Sinvula ◽

Khaled Mohamed Abo-Al-Ez ◽

Mohamed Tariq Kahn

Keyword(s):

Monitoring System ◽

Renewable Energy Sources ◽

Electronic Devices ◽

Harmonic Distortion ◽

Large Power ◽

High Penetration ◽

Point Of Common Coupling ◽

Common Coupling ◽

Power Utilities ◽

The Individual

Most power utilities within Southern Africa are faced with the challenges of harmonic distortion due to the high penetration of renewable energy sources (RES) and the use of electronic devices. There is an excessive total harmonic distortion (THD) measured at the point of common coupling (PCC). In this paper, a proposed harmonic monitoring system for large power users (LPUs) is developed. This proposed system considers harmonic limits of the individual and THD of the customers allowed injecting into the network, which should be part of the contractual electricity supply agreement (ESA). Hence, it will enable the monitoring of harmonic distortion to be smooth by determining whether the customer has passed or failed compliance for individual harmonic order and the THD of the voltage. The measurements of harmonic distortion are done using the Unipower power quality (PQ) analyzers that are connected at different points within the industrial network. Measurements of harmonic distortion of an industrial site are compared to the simulation results performed by DIgSILENT software to validate the proposed harmonic monitoring system. Based on the validation results, it is recommended that the ESA between the power utilities and the customers should consist of the harmonic limits.

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Optimal Harmonic Mitigation in Distribution Systems with Inverter Based Distributed Generation

Applied Sciences ◽

10.3390/app11020774 ◽

2021 ◽

Vol 11 (2) ◽

pp. 774 ◽

Cited By ~ 3

Author(s):

Ahmed S. Abbas ◽

Ragab A. El-Sehiemy ◽

Adel Abou El-Ela ◽

Eman Salah Ali ◽

Karar Mahmoud ◽

...

Keyword(s):

Power Quality ◽

Distributed Generation ◽

Distribution System ◽

Distribution Systems ◽

Renewable Energy Sources ◽

Harmonic Distortion ◽

Planning Problem ◽

Voltage Profile ◽

Harmonic Mitigation ◽

The Impact

In recent years, with the widespread use of non-linear loads power electronic devices associated with the penetration of various renewable energy sources, the distribution system is highly affected by harmonic distortion caused by these sources. Moreover, the inverter-based distributed generation units (DGs) (e.g., photovoltaic (PV) and wind turbine) that are integrated into the distribution systems, are considered as significant harmonic sources of severe harmful effects on the system power quality. To solve these issues, this paper proposes a harmonic mitigation method for improving the power quality problems in distribution systems. Specifically, the proposed optimal planning of the single tuned harmonic filters (STFs) in the presence of inverter-based DGs is developed by the recent Water Cycle Algorithm (WCA). The objectives of this planning problem aim to minimize the total harmonic distortion (THD), power loss, filter investment cost, and improvement of voltage profile considering different constraints to meet the IEEE 519 standard. Further, the impact of the inverter-based DGs on the system harmonics is studied. Two cases are considered to find the effect of the DGs harmonic spectrum on the system distortion and filter planning. The proposed method is tested on the IEEE 69-bus distribution system. The effectiveness of the proposed planning model is demonstrated where significant reductions in the harmonic distortion are accomplished.

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A Review of Virtual Inertia Techniques for Renewable Energy-Based Generators

10.5772/intechopen.92651 ◽

2020 ◽

Author(s):

Ana Fernández-Guillamón ◽

Emilio Gómez-Lázaro ◽

Eduard Muljadi ◽

Ángel Molina-Garcia

Keyword(s):

Renewable Energy ◽

Power Systems ◽

Power System ◽

Power Plants ◽

Control Strategies ◽

Renewable Energy Sources ◽

Extensive Discussion ◽

Renewable Sources ◽

Virtual Inertia ◽

Alternative Sources

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.

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Converter-driven Stability Analysis of Power Systems Integrated with Hybrid Renewable Energy Sources

10.20944/preprints202105.0103.v1 ◽

2021 ◽

Author(s):

Jianqiang Luo ◽

Yiqing Zou ◽

Siqi Bu

Keyword(s):

Renewable Energy ◽

Stability Analysis ◽

Power Systems ◽

Power System ◽

Dynamic Models ◽

Renewable Energy Sources ◽

Energy Sources ◽

Power Electronic ◽

Modal Interaction ◽

Hybrid Renewable Energy

Various renewable energy sources such as wind power and photovoltaic (PV) have been increasingly integrated into the power system through power electronic converters in recent years. However, power electronic converter-driven stability issues under specific circumstances, for instance, modal resonances might deteriorate the dynamic performance of the power systems or even threaten the overall stability. In this paper, the integration impact of a hybrid renewable energy source (HRES) system on modal interaction and converter-driven stability is investigated in an IEEE 16-machine 68-bus power system. Firstly, an HRES system is introduced, which consists of full converter-based wind power generation (FCWG) and full converter-based photovoltaic generation (FCPV). The equivalent dynamic models of FCWG and FCPV are then established, followed by the linearized state-space modeling. On this basis, converter-driven stability analyses are performed to reveal the modal resonance mechanisms of the interconnected power systems and the modal interaction phenomenon. Additionally, time-domain simulations are conducted to verify effectiveness of dynamic models and support the converter-driven stability analysis results. To avoid detrimental modal resonances, an optimization strategy is further proposed by retuning the controller parameters of the HRES system. The overall results demonstrate the modal interaction effect between external AC power system and the HRES system and its various impacts on converter-driven stability.

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