Vu Van Thong

Virtual synchronous generator: Laboratory scale results and field demonstration

This paper describes an approach to demonstrate the operation of virtual synchronous generators (VSG) in practical distribution systems. After an extensive simulation phase at laboratory scale, the field demonstration is planned at two sites located in the Netherlands and in Romania, for small VSGs of 10 × 5 kW and one large VSG of 100 kW respectively.

Transmission system operation concerns with high penetration level of distributed generation

The increasing connection of distributed generation at distribution levels from a certain penetration level may not only influence the operation and design of distribution systems, but affect to the operation and stability of transmission system as well. This paper aims to study the impact of distributed generation on the frequency and voltage stability. The results show that depending on the penetration levels and DG technologies, the impacts are different.

Influences of large penetration of distributed generation on N-1 safety operation

The incentive to operate less polluting energy sources and the electricity liberalization has opened opportunities for the increasing penetration of distributed generation (DG) in the power system. Due to the locally available resources and small scale, DG units are mostly connected at the distribution level. This does not only have impact on the distribution system operation, but on the transmission system as well. In this study, the impact of DG on N-1 safety (contingency) of the transmission system is studied in detail with different DG technologies at given penetration levels.

Penetration level of distributed energy resources with anti-islanding criteria and secure operation of power system

Many recent blackouts might raise a concern on how the introduction of distributed energy resources or distributed generation (DG) into the network influences its secure operation in terms of dynamic performance. The anti-islanding criteria of DG may harm the secure operation of the power system. In this paper, the maximum penetration level of DG is determined using a dynamic study. Tested systems are used to study. The results show that the protection settings have an influence the maximum penetration of DG and the system secure operation

Electricity supply, irregularities, and the prospect for solar energy and energy sustainability in Sub-Saharan Africa

Countries in Sub-Saharan Africa (SSA) are faced with the problem of expanding urban growth and demographic shift, necessitating the need to achieve a sustainable rate of positive economic growth. To move toward a sustainable future, many reforms have been implemented, including in the energy sector. Reforms in the energy sector will lead to a secure future energy supply, open globalised energy market, as well as providing basic energy needs. Unfortunately electrical energy production within SSA countries is primarily by wood fueled power stations and large hydroschemes (with oil and gas to a lesser extent). Large hydropower systems are environmentally destructive, and the combustion of wood generates millions of tons of carbon dioxide and green house gas emissions. The recent price fluctuations of crude oil and natural gas and the inconsistent and insufficient power supply have further increased public dissatisfaction. This paper demonstrates how the SSA region with its natural resources is capable of pro...

Using Distributed Generation to Support and Provide Ancillary Services for the Power System

The contribution of small distributed generation (DG) in power generation is significant nowadays. The influence of DG on the system operation protocol is increasing with the increase of the DG penetration level in the power system. However, DG is still treated as negative load. How to use it in an active way is still an open question. DG is not only playing an important role in power generation, but also can be a source providing ancillary services. This paper gives general discussions how to use DG to provide ancillary services. Due to the local connection and near consumers, the contribution of DG is significant with local control variables such as voltage regulation or power loss reduction.

Measurement and remote monitoring for virtual synchronous generator design

The future power system will integrate widely distributed energy resources (DER) interfaced by power electronics units, which may cause a reduction of the system inertia, resulting in non-compatibility with existing control algorithms and settings. Additional rotational-inertia can be provided to the system if many DER units combined with relative small storage units operate like virtual synchronous generators (VSG). This paper presents the measurement layer and the associated monitoring campaign needed for a VSG design and operation.

Overview and Comparisons of Existing DG Interconnection Standards and Technical Guidelines

Owing to technology innovations, electricity market liberalization and environmental concern, many small-scale generators, or distributed generation (DG), using both renewable energy and fossil fuel resources, are rapidly brought to the power networks. The connection of DG may change the operation and the topology of distribution systems. This may influence voltage control, protection regime, safety issues, etc. of the system when coupling, operating, and shutting down small generator units. Technical requirements and standards of DG interconnection are different from country to country, making international harmonization difficult. This paper aims to give an overview and to discuss those differences.

Benefits and Impact of Using Small Generators for Network Support

Distributed generation (DG) is playing an increasing role not only in electric power generation, as backup sources to increase the supply reliability, but also as a possible source providing ancillary services for grid support. The penetration level of DG in some particular power systems is high and growing, leading to a great concern how to employ DG in an efficient and effective way for network control and support. This paper aims to give an overview of technical, economical and environmental aspects when integrating DG to the power system. The contribution ability of DG to ancillary services is also investigated.

Energy sustainability in Sub-Saharan Africa

Sub-Saharan African countries are today confronted with the problem of urban and demographic growths thus needing to reach a sustainable rate of positive economic growth. In order to meet this sustainability, many reforms are being carried out among which is the energy sector which will lead to future energy supply in an open globalised energy market as well as providing the basic energy needs. One of such methods involves the use of distributed generation (DG) which is always located closed to consumption points for rapid electrification. How ever, the use of DG involves the need of a stable network which most often is lacking in Sub-Saharan African countries thus growing concern of DG on their loosely integrated grids.