Contribution of the Liquid Phase on Direct Current Interruption by a Forced Fluid Flow

The rising amount of medium voltage direct-current systems requires novel solutions for DC switching. The interruption of direct-currents is accomplished by enforcing a current zero, which can only be achieved when the arc voltage of the switching device raises above the grid voltage. On way to achieve this, is to force the arc into narrow channels by an imposed fluid flow. The increasing arc voltage than not only depends on increased cooling due to phase change but also on the mechanical elongation of the arc enforced by the fluid stream. Hence, the interaction of the fluid flow and the arc should be studied in more detail. For this, the switching characteristic of selected dielectric liquids are examined. Using a self developed setup, direct-current interruptions at a constant voltage of 10kV were carried out. Our results indicate, that the process of enforcing a current decay strongly depends on the mechanical resistance of the liquids to deform under the pressure of the electric arc

Transient Arc Characteristic of a Commutation Switch Utilizing High Velocity Contact Separation

Commutation circuits are commonly used for low on state resistance and high current interruption capability if this can not be achieved by a single device or single current switching path. In case of fault detection, a very fast commutation of the current from the low-impedance main current path into the parallel high-current interrupting path is necessary. For single usage applications a low-cost approach is the utilization of a pyrotechnical switch in the low-impedance path. Compared to other electromechanical switches, those switches provide very high velocity of contact separation and thus a fast arc voltage rise with short commutation times. Here, measurements of the contact movement of a pyrotechnical switch were carried out using optical high speed imaging and an arc elongation up to 100ms−1 was calculated. From this, transient arc characteristics were measured in a simplified commutation network during the period until current zero in the low-impedance main current path

INSPIRE-MMTIS: overlap in standards related to the Delegated Regulation (EU) 2017/1926

The COMMISSION DELEGATED REGULATION (EU) 2017/1926 of 31 May 2017 supplementing Directive 2010/40/EU of the European Parliament and of the Council with regard to the provision of EU-wide multimodal travel information services provides a list of static and dynamic data categories to be made available by Member States through the National Access Points. A range of data standards are required for the publication of such data categories, of which a subset (20 data categories) refers to static spatial data which are also linked to the INSPIRE Directive (Directive 2007/2/EC). Within this policy context, this document is the final report of the INSPIRE-MMTIS study, aimed to identify and analyse the overlaps and gaps existing among the relevant standards to be used for the sharing and reuse of data under the remit of the above mentioned Delegated Regulation. Recommendations for both data providers and data users on how to deal with the overlaps/gaps have been formulated, based on a series of use cases. The analysis performed in the study represents a first step to support Member States in the implementation of the MMTIS Regulation. Results demonstrate that the analysed standards are sufficient to start implementing the Regulation, although several recommendations show that further work is necessary (given e.g. gaps in standardisation and the need for European profiles and conversion tools).JRC.B.6-Digital Econom