Distributed generation and renewables - Power Quality

Status

completed

Motivation

The increasing amount of electrical generation with renewable energy resources, like wind, sun, biomass and water, leads to radical changes in the Austrian electrical power supply system. Former central structures will become more and more decentralised and former unidirectional power flow will be reversed to bidirectional power flow in the lower voltage levels.

With the increasing share of distributed generation fundamental issues, like capacity planning, stability, protection coordination and mainly the quality of supply (Power Quality - PQ) come to the fore again. In particular the Power Quality receives much interest due to increasing sensibility of customers and to the fear that quality and reliability of electricity supply will be jeopardised by a higher share of distributed generation. The issue of reliability will become an increasing barrier for the ambitious change toward an ecological electricity supply and therefore hamper the achievement of important environmental and energy policy targets.

The main objective of this project was to reduce the technical and organisational barriers and to show how renewable energy resources can actively contribute to an enhancement of Power Quality.

Approach

On the basis of the know-how of the project partners the current framework for distributed generation was analyzed and strategies and concepts were developed. Within the scope of a measurement campaign accompanied by analytic network simulations the power quality at representative sites was investigated.

As a next step a concrete implemented concept should show how distributed generation can actively enhance the power quality by using suitable technologies. Additionally within a feasibility survey obstacles and opportunities for the improvement of power quality through distributed generation were identified. The technical potentials for an efficient and multifunctional use of distributed generation for power quality improvement were estimated.

Results

The analyses of the framework for distributed generation showed that rules are not transparent and not harmonised and they provide poor incentives for distributed generation.

The measurement campaign at sites with distributed generation showed that apart from the voltage rise effect there is generally no significant influence of the distributed generation units on the parameters of Power Quality. Within the project it was illustrated that technologies for improvement of Power Quality are available and that they are working. Due to the current organisational and economic framework these technologies still do not play any relevant role concerning the delivery of ancillary services.

Conclusion

The active integration of distributed generation units could contribute to the improvement of Power Quality. In addition to the necessary framework which is currently missing, the confidence of network operators in this concept of integrated distributed generation providing ancillary services is lacking. Therefore it is necessary to address this lack of confidence and demonstrate the feasibility within a broad implementation of such concepts in real networks.

Project leader (Contact address)

DI Roland Bründlinger
arsenal research - Österreichisches Forschungs- und Prüfzentrum Arsenal GmbH
Faradaygasse 3
A-1030 Wien
Tel: +43 (0) 50/550 6351
Fax: +43 (0) 50/550 6613
E-Mail: roland.bruendlinger@arsenal.ac.at
Internet: Arsenal Research

Project partners

VATECH ELIN EBG Elektronik GmbH (Werkvertragspartner)
oekostrom AG (Werkvertragspartner)
Stadtwerke Hartberg GmbH
(Werkvertragspartner)