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In this paper, a new simulation model is developed to be able to simulate diesel genset smart grid interconnection by keeping in view future requirements of the grids and grid codes. The simulations are carried out in Matlab/Simulink environment. An example case is based on 1200 kW variable speed diesel genset with permanent magnet synchronous generator (PMSG). The simulations are carried out for various dynamic behaviours of PMSG and their protection and control facilities, which are necessary in normal operating conditions and in a range of disturbed operating conditions in order to preserve or to re-establish system security. Various faults (e.g. disturbances) have been induced in the distribution system and the robustness of the network has been analysed to make sure continuous supply of electricity to the consumers in the future smart grid environment.

On-line partial discharge (PD) measurements can be used as a condition monitoring tool to detect falling/leaning trees on the covered-conductor (CC) overhead distribution networks. PD measurements conducted in the high voltage (HV) laboratory are less affected by electromagnetic disturbances (EMD). However, on the other hand, on-line/on-site PD measurements conducted in smart distribution networks are often affected by several disturbances. Extracting low level PD signal from noisy backgrounds is a major challenge for on-line condition monitoring. In this paper, wavelet transform (WT) technique is proposed as a powerful tool to de-noise on-line PD signals in CC overhead distribution lines, which are completely buried by electromagnetic interference (EMI). The on-line PD signals are captured in the laboratory environment and on-site PD measurements are simulated. The principle of denoising based on multi-resolution signal decomposition (MSD) is implemented. The validation of WT technique is carried out by comparing its effectiveness with other available filtering techniques. Rogowski coil is used as a PD sensor to capture PD signals in this specific application. In the future, the proposed method will be implemented in a real-life environment to get more stable and reliable on-line/on-site PD measurement results for enhanced fault detection in smart distribution networks.

The experimental evaluation of Rogowski coil performance for locating partial discharge (PD) in energized covered-conductor (CC) overhead lines is performed. A multi-end measuring point is introduced, where the Rogowski coils looped around the CC line at three different locations and connected to the oscilloscope for measurements. The tests are carried out concerning different measurement conditions such as off-line and on-line PD measuring systems. For off-line measurements, the calibrator pulse is used to inject PD source to the CC overhead lines. Meanwhile for on-line measurement, CC line is energized by a 110/20 kV power transformer and the concept of twisted-coil around the CC is introduced in order to produce a pulse similar to the PD source. The performance of Rogowski coil is tested in noisy environment. Chirp detector is used as a signal processing tool to extract the high frequency signals in order to determine the time of arrival (TOA) signals at each measuring sensors. The locator function algorithm for multi-end measurement is developed. The results obtained from this work confirm the capability of the Rogowski coil to measure and locate the high frequency PD source on the CC line in consistent with energizing AC source. Meanwhile, using the locator function algorithm developed, the localization of PD source point on CC overhead lines is found out without the need to know the propagation velocity of the signals.

In this paper, overvoltage transients are investigated and mitigated when a three-phase short-circuit occurs in cable lateral connected with medium voltage (MV) overhead line and fuse is operated. The transients are studied using EMTP-ATP simulation environment and the need of metal oxide varistors (MOVs) is investigated. The cable laterals consist of sub-laterals and their effect on reducing transients is also investigated. The surge arresters are installed at the junction of overhead line and cable and at far end of the cable near short-circuit point. The different mitigation methods are tested and optimal protection scheme to reduce overvoltages is proposed on the basis of surge arresters locations and sub-lateral connections.

The objective of this report is to compile various smart grid concepts, architectures and details of associated technologies implemented worldwide. The survey is based on initiatives taken by EU and IEA (e.g. ETP, EEGI, EERA and IEA DSM) and description of projects conducted in Europe and US (e.g. FENIX, ADDRESS, EU-DEEP, ADINE, GridWise and SEESGEN-ICT). The report presents drivers, visions and roadmaps to develop smart grids in US, China and India. The survey encompasses various smart grid concepts, i.e. development of virtual power plant, active demand in consumer networks, DER aggregation business, active distribution network and ICT applications to develop intelligent future grids. The comparison is carried out on the basis of commercial, technological and regulatory aspects. In addition, the existing features of smart grid technology and challenges faced to implement it in Finnish environment are addressed. As a matter of fact, the implementation of smart grid is consisting of more than any one technology, therefore, this transition will not be so easy. In the end, a fully realised smart grid will be beneficial to all the stakeholders. Smart grid is an evolution towards an optimised and sustainable energy system which is more intelligent, efficient and reliable and it has positive influence on the climate change.