Biblio
Harmonic distortions come into existence in the power system not only due to nonlinear loads of consumers but also due to custom power devices used by power utilities. These distortions are harmful to the power networks as these produce over heating of appliances, reduction in their life expectancy, increment in electricity bill, false tripping, etc. This paper presents an effective, simple and direct approach to identify the problematic cause either consumer load or utility source or both responsible for harmonics injection in the power system. This technique does not require mathematical model, historical data and expert knowledge. The online methodology is developed in the laboratory and tested for different polluted loads and source conditions. Experimental results are found satisfactory. This proposed technique has substantial potential to determine the problematic cause without any power interruption by plug and play operation just like CCTV.
With the rapid development of the smart grid, a large number of intelligent sensors and meters have been introduced in distribution network, which will inevitably increase the integration of physical networks and cyber networks, and bring potential security threats to the operating system. In this paper, the functions of the information system on distribution network are described when cyber attacks appear at the intelligent electronic devices (lED) or at the distribution main station. The effect analysis of the distribution network under normal operating condition or in the fault recovery process is carried out, and the reliability assessment model of the distribution network considering cyber attacks is constructed. Finally, the IEEE-33-bus distribution system is taken as a test system to presented the evaluation process based on the proposed model.
In this paper, the design of an event-driven middleware for general purpose services in smart grid (SG) is presented. The main purpose is to provide a peer-to-peer distributed software infrastructure to allow the access of new multiple and authorized actors to SGs information in order to provide new services. To achieve this, the proposed middleware has been designed to be: 1) event-based; 2) reliable; 3) secure from malicious information and communication technology attacks; and 4) to enable hardware independent interoperability between heterogeneous technologies. To demonstrate practical deployment, a numerical case study applied to the whole U.K. distribution network is presented, and the capabilities of the proposed infrastructure are discussed.