Performance evaluation of PV penetration at different locations in a LV distribution network connected with an off-load tap changing transformer

<span>Solar photovoltaic (PV) power generation has shown a worldwide remarkable growth in recent years. In order to achieve the increasing energy demand, a large number of residential PV units are connected to the low voltage (LV) distribution networks. However, high integration of solar PV could cause negative impacts on distribution grids leading to violations of limits and standards. The voltage rise has been recognized as one of the major implications of increased PV integration, which could significantly restrict the capacity of the distribution network to support higher PV penetration levels. This study addresses the performance of the off-load tap changing transformer under high solar PV penetration and a detailed analysis has been carried out to examine the maximum allowable PV penetration at discrete tap positions of the transformer. The maximum PV penetration has been determined by ensuring that all nodal voltages adhere to grid voltage statutory limits. The simulation results demonstrate that the first two tap positions could be adopted to control the grid voltage under higher PV penetrations thus facilitating further PV influx into the existing network.</span>

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Autonomous Controller for Flexible Operation of Heat Pumps in Low-Voltage Distribution Network

Energies ◽

10.3390/en12081482 ◽

2019 ◽

Vol 12 (8) ◽

pp. 1482 ◽

Cited By ~ 2

Author(s):

Rakesh Sinha ◽

Birgitte Bak-Jensen ◽

Jayakrishnan Radhakrishna Radhakrishna Pillai

Keyword(s):

Thermal Energy ◽

System Analysis ◽

Low Voltage ◽

Cold Water ◽

Distribution Network ◽

Distribution Networks ◽

Voltage Regulation ◽

Heat Pumps ◽

Analysis Tool ◽

Grid Voltage

This paper aims to unleash the potential of a heat pump (HP) and its storage system, as a flexible consumer load, in the low-voltage (LV) distribution network by introducing an autonomous controller. Steady-state analysis using DigSILENT Power Factory, a power system analysis tool, is performed to verify the proposed hypothesis. The proposed controller manages to operate the individual HP and storage within the recommended operating limits of grid voltage, by sharing flexibility within the specific network. It has the capability of sensing local key control parameters for scheduling, re-scheduling, and decision-making on the operation of individual HPs. It also takes the thermal energy comfort of individual consumers into consideration. Measurement of local parameters such as grid voltage, supply temperature and level of cold water in the storage tank defines the priority for operation of HPs based on operating delays for turning it on and off. This enhances the sharing of flexibility for proper coordination, control, and management of HP systems in LV distribution networks with mutual technical benefits. From the results, the application of the proposed controller is found to be effective to manage grid congestions and local voltage regulation, satisfying the thermal energy requirements of the customer.

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Monte Carlo analysis for solar PV impact assessment in MV distribution networks

Indonesian Journal of Electrical Engineering and Computer Science ◽

10.11591/ijeecs.v23.i1.pp23-31 ◽

2021 ◽

Vol 23 (1) ◽

pp. 23

Author(s):

Dilini Almeida ◽

Jagadeesh Pasupuleti ◽

Shangari K. Raveendran ◽

M. Reyasudin Basir Khan

Keyword(s):

Monte Carlo ◽

Distribution Network ◽

Distribution Networks ◽

Monte Carlo Analysis ◽

Solar Pv ◽

Probabilistic Framework ◽

Load Demand ◽

Pv Generation ◽

Pv Penetration ◽

The Impact

The rapid penetration of solar photovoltaic (PV) systems in distribution networks has imposed various implications on network operations. Therefore, it is imperative to consider the stochastic nature of PV generation and load demand to address the operational challenges in future PV-rich distribution networks. This paper proposes a Monte Carlo based probabilistic framework for assessing the impact of PV penetration on medium voltage (MV) distribution networks. The uncertainties associated with PV installation capacity and its location, as well as the time-varying nature of PV generation and load demand were considered for the implementation of the probabilistic framework. A case study was performed for a typical MV distribution network in Malaysia, demonstrating the effectiveness of Monte Carlo analysis in evaluating the potential PV impacts in the future. A total of 1000 Monte Carlo simulations were conducted to accurately identify the influence of PV penetration on voltage profiles and network losses. Besides, several key metrics were used to quantify the technical performance of the distribution network. The results revealed that the worst repercussion of high solar PV penetration on typical Malaysian MV distribution networks is the violation of the upper voltage statutory limit, which is likely to occur beyond 70% penetration level.

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Harmonic Analysis of Grid-Connected Solar PV Systems with Nonlinear Household Loads in Low-Voltage Distribution Networks

Sustainability ◽

10.3390/su13073709 ◽

2021 ◽

Vol 13 (7) ◽

pp. 3709

Author(s):

Syed Muhammad Ahsan ◽

Hassan Abbas Khan ◽

Akhtar Hussain ◽

Sarmad Tariq ◽

Nauman Ahmad Zaffar

Keyword(s):

Low Voltage ◽

Harmonic Distortion ◽

Distribution Networks ◽

Total Harmonic Distortion ◽

Base Case ◽

Solar Pv ◽

Voltage Profile ◽

Nonlinear Loads ◽

Pv Systems ◽

Pv Penetration

Grid-connected rooftop and ground-mounted solar photovoltaics (PV) systems have gained attraction globally in recent years due to (a) reduced PV module prices, (b) maturing inverter technology, and (c) incentives through feed-in tariff (FiT) or net metering. The large penetration of grid-connected PVs coupled with nonlinear loads and bidirectional power flows impacts grid voltage levels and total harmonic distortion (THD) at the low-voltage (LV) distribution feeder. In this study, LV power quality issues with significant nonlinear loads were evaluated at the point of common coupling (PCC). Various cases of PV penetration (0 to 100%) were evaluated for practical feeder data in a weak grid environment and tested at the radial modified IEEE-34 bus system to evaluate total harmonic distortion in the current (THDi) and voltage (THDv) at PCC along with the seasonal variations. Results showed lower active, reactive, and apparent power losses of 1.9, 2.6, and 3.3%, respectively, with 50% solar PV penetration in the LV network as the voltage profile of the LV network was significantly improved compared to the base case of no solar. Further, with 50% PV penetration, THDi and THDv at PCC were noted as 10.2 and 5.2%, respectively, which is within the IEEE benchmarks at LV.

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Photovoltaic Generation Impact Analysis in Low Voltage Distribution Grids

Energies ◽

10.3390/en13174347 ◽

2020 ◽

Vol 13 (17) ◽

pp. 4347

Author(s):

Gregorio Fernández ◽

Noemi Galan ◽

Daniel Marquina ◽

Diego Martínez ◽

Alberto Sanchez ◽

...

Keyword(s):

Impact Analysis ◽

Time Series Data ◽

Low Voltage ◽

Distribution Networks ◽

Series Data ◽

Solar Pv ◽

Smart Meters ◽

Photovoltaic Generation ◽

Electric Vehicle Charging ◽

Distribution Grids

Due to a greater social and environmental awareness of citizens, advantageous regulations and a favourable economic return on investment, the presence of photovoltaic (PV) installations in distribution grids is increasing. In the future, not only a significant increase in photovoltaic generation is expected, but also in other of the so-called distributed energy resources (DER), such as wind generation, storage, electric vehicle charging points or manageable demands. Despite the benefits posed by these technologies, an uncontrolled spread could create important challenges for the power system, such as increase of energy losses or voltages out-of-limits along the grid, for example. These issues are expected to be more pronounced in low voltage (LV) distribution networks. This article has two main objectives: proposing a method to calculate the LV distributed photovoltaic generation hosting capacity (HC) that minimizes system losses and evaluating different management techniques for solar PV inverters and their effect on the hosting capacity. The HC calculation is based on a mixture of deterministic methods using time series data and statistical ones: using real smart meters data from customers and generating different combinations of solar PV facilities placements and power to evaluate its effect on the grid operation.

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Rooftop Solar PV Penetration Impacts on Distribution Network and Further Growth Factors—A Comprehensive Review

Electronics ◽

10.3390/electronics10010055 ◽

2020 ◽

Vol 10 (1) ◽

pp. 55

Author(s):

Busra Uzum ◽

Ahmet Onen ◽

Hany M. Hasanien ◽

S. M. Muyeen

Keyword(s):

Solar Energy ◽

Power Quality ◽

Distribution System ◽

Renewable Energy Sources ◽

Distribution Network ◽

System Stability ◽

Solar Pv ◽

Voltage Quality ◽

Solution Methods ◽

Pv Penetration

In order to meet the electricity needs of domestic or commercial buildings, solar energy is more attractive than other renewable energy sources in terms of its simplicity of installation, less dependence on the field and its economy. It is possible to extract solar energy from photovoltaic (PV) including rooftop, ground-mounted, and building integrated PV systems. Interest in rooftop PV system applications has increased in recent years due to simple installation and not occupying an external area. However, the negative effects of increased PV penetration on the distribution system are troublesome. The power loss, reverse power flow (RPF), voltage fluctuations, voltage unbalance, are causing voltage quality problems in the power network. On the other hand, variations in system frequency, power factor, and harmonics are affecting the power quality. The excessive PV penetration also the root cause of voltage stability and has an adverse effect on protection system. The aim of this article is to extensively examines the impacts of rooftop PV on distribution network and evaluate possible solution methods in terms of the voltage quality, power quality, system protection and system stability. Moreover, it is to present a comparison of the advantages/disadvantages of the solution methods discussed, and an examination of the solution methods in which artificial intelligence, deep learning and machine learning based optimization and techniques are discussed with common methods.

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Impact of Photovoltaic Plant Outputs in Distribution Networks

MATEC Web of Conferences ◽

10.1051/matecconf/201822504024 ◽

2018 ◽

Vol 225 ◽

pp. 04024 ◽

Cited By ~ 1

Author(s):

Abid Ali Jamali ◽

Nursyarizal Mohd Nor ◽

Taib Ibrahim ◽

Mohd Fakhizan Romlie ◽

Zahid Khan

Keyword(s):

Low Voltage ◽

Distribution Networks ◽

Weather Data ◽

Time Varying ◽

Solar Pv ◽

Farm Life ◽

Plant Yields ◽

Module Efficiency ◽

Photovoltaic Plant ◽

The Impact

This paper evaluates the potential of Quaid-e-Azam Solar Park (QASP), Pakistan and examines its impact on distribution networks. To estimate the PV plant yields, solar park’s historical hourly weather data from the years 2000 - 2014 is used. For handling of such huge data, the yearly data is partitioned into four seasons. Further, the seasonal data is modelled by using Beta Probability Density Function (PDF) and a 24 hour solar curve for each season is generated. The solar farm power outputs are tested in IEEE 33 bus distribution network by using time-varying seasonal hourly loads, meanwhile system losses and bus voltages are calculated. The results show that with the passage of time, the impact of solar PV power on reduction of system losses gradually decrease due to yearly degradation of PV module efficiency. System losses at end of PV farm life are 10 - 12% higher than those losses as in the first year. Furthermore, low voltage buses also pose to risk as system voltages also start to decrease. From the analysis, it is suggested that for maintaining the quality of network, time varying detailed assessments should be performed during the calculations of sizing of distributed generation.

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Voltage Protection and Harmonics Cancellation in Low Voltage Distribution Network

International Journal of New Practices in Management and Engineering ◽

10.17762/ijnpme.v7i04.68 ◽

2018 ◽

Vol 7 (04) ◽

pp. 01-07

Author(s):

Prof. Amruta Bijwar, Prof. Madhuri Zambre

Keyword(s):

Direct Current ◽

Current Distribution ◽

Low Voltage ◽

Distribution Network ◽

Control Unit ◽

Future Generation ◽

Distribution Networks ◽

Current Control ◽

Voltage Distribution ◽

Monitor Function

Nowadays low voltage distribution network is considered as worldwide future generation distribution network. But the major concern is harmonics generation and steps taken to cancel those harmonics. In our proposed work, low voltage distribution network is designed with low voltage and harmonics are cancelled in our method. The combination of current control unit and voltage control unit will give extra reliable power solution to increase the required capacity of low voltage grids. The high voltage protection gears are used in worst environment for low voltage and low current distribution network test is preferable to assess a variety of operation uniqueness. Therefore, it has few restrictions in implementation of economic in addition to process methodologies. In our work a 48V direct current base up-scale low voltage distribution network test is urbanized to allow the copy and surveillance of a variety of phenomenon of direct current distribution networks. The proposed system provide stretchy pattern ability by introduce S-connectors and T-connectors module that will be proscribed distantly, and near real time monitor function through by means of a data acquisition system associated toward the nodes. Each connector be able to calculate Power, Voltage and current with up to 250 kHz frequency. To calculate power quality and to understand the performance of the distribution network, frequency analysis is required along with collected data.

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Rancang Bangun Alat Deteksi Stabilitas Tegangan Jangka Panjang Pada Jaringan Distribusi Tegangan Rendah

Electrician ◽

10.23960/elc.v12n2.2078 ◽

2019 ◽

Vol 12 (2) ◽

pp. 33

Author(s):

Osea Zebua ◽

Noer Soedjarwanto ◽

Jemi Anggara

Keyword(s):

Power Distribution ◽

Voltage Stability ◽

Low Voltage ◽

Distribution Network ◽

Distribution Networks ◽

Current Data ◽

Voltage Distribution ◽

Power Distribution Networks ◽

Long Time

Intisari — Stabilitas tegangan telah menjadi perhatian yang penting dalam operasi jaringan distribusi tenaga listrik. Ketidakstabilan tegangan dapat menyebabkan kerusakan pada peralatan-peralatan listrik bila terjadi dalam waktu yang lama. Makalah ini bertujuan untuk merancang dan membuat peralatan deteksi stabilitas tegangan jangka panjang pada jaringan tegangan rendah. Sensor tegangan dan sensor arus digunakan untuk memperoleh data tegangan dan arus. Mikrokontroler Arduino digunakan untuk memproses perhitungan deteksi stabilitas tegangan jangka panjang dari data tegangan yang diperoleh dari sensor. Hasil deteksi kondisi stabilitas tegangan ditampilkan dengan indikator lampu led. Hasil pengujian pada jaringan distribusi tegangan rendah tiga fasa menunjukkan bahwa peralatan dapat mendeteksi gangguan stabilitas tegangan jangka panjang secara online dan dinamis.Kata kunci — Deteksi, stabilitas tegangan jangka panjang, jaringan distribusi tegangan rendah. Abstract — Voltage stability has become important concern in the operation of electric power distribution networks. Voltage instability can cause damage to electrical equipments if it occurs for a long time. This paper aims to design and build long-term voltage stability detection equipment on low-voltage network. Voltage sensors and current sensors are used to obtain voltage and current data. The Arduino microcontroller is used to process calculation of long-term voltage stability detection from data obtained from the sensors. The results of detection of voltage stability conditions are displayed with the LED indicators. Test result on three-phase low-voltage distribution network shows that equipment can detect long–term voltage stability disturbance online and dynamically.Keywords— Detection, long-term voltage stability, low-voltage distribution network.

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