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This paper presents the design and implementation of an electronic ballast for powering a fluorescent lamp. The purpose of this work is to improve the efficiency of the ballast by implementing a Series Resonant Inverter (SRI) in half-bridge configuration instead classic Series-Parallel Resonant (SPRI); in order to allow to provide the voltage steady state of the lamp. By other hand, this DC-AC converter will supply the voltage lamp ignition. Results on the proposed experimental prototype, using a fluorescent lamp of 32W, shows a better efficiency compared to traditional SPRI configurations., QC 20170505

The automatic frequency containment reserve (FCR-N) is in place to keep the electric frequency within the interval 50.0 +/-0.1 Hz during normal operation. This function is mainly provided by a number of hydropower plants where the turbine governor is set to control the discharge in proportion to the measured frequency deviation. In later years it has been shown that the disturbance damping is very low in an interval around 1160 Hz and it is believed that proper tuning of the turbine governors that provide FCR-N can help mitigating this problem. New regulator settings have been suggested to improve the performance of the FCR-N, yet keeping the system robust and the wear on participating units at a minimum. It is now desired to investigate the possible effects of new governor settings on the overall power system frequency response. In a word, the overall performance for new governor settings are tested in a large scale power system model in this thesis paper. The frequency response with the newly suggested governor settings have been investigated when introducing a disturbance into the system. Secondly, the effects of the new governor settings on electro-mechanical oscillations are also investigated., QC 20170214

The increasing integration of renewables into the grid based on power electronics converters interfaces is affecting the power systems dynamics, requiring effective monitoring and visualisation to provide appropriate assessment during extreme events. The coherent group identification in power systems is of importance for dynamic studies and transmission capability improvement. This study analyses the coherency based on the mode shapes, the application of the Koopman mode analysis (KMA) and a Prony analysis (PA) on-line variation for the identification of coherent groups in power systems. KMA and PA use the voltage angle measurements obtained from simulation. The clustering of the coherent groups are evaluated in two test systems. The coherency methods are also evaluated taking into account the impact of a large gradual scale inclusion of non-synchronous generation under different penetration level cases. From the comparison and visualisation of the different methods it is possible to observe the impact of the large inclusion of non-synchronous generation on the coherency., QC 20160902

The large scale penetration of non-synchronous generation based power electronics converters interfaces in current power systems is modifying their dynamic characteristics. The observation, monitoring and supervision of the electromechanical oscillation changes due to this integration is a requirement in order to protect the system from undesired events. This paper uses the Prony analysis to estimate the critical modes by using the tie-lines which interconnect the operative areas as measurement points and evaluating the impact of the large gradual scale inclusion of non-synchronous generation on power systems. The modes monitoring involved in the transient dynamic response are shown in the different penetration level cases. From the computed measurements, the frequency and damping variation in the different cases studied on the test system is obtained, which shows the impact of the large inclusion of non-synchronous generation., QC 20160905

Cyber Physical Energy Systems (CPES) development requires the combination of distributed intelligence to fulfill the future complex tasks and reach the increase the energy demands. Electrical Industrial Systems (EIS) are in continuous evolving integrating new technologies allowing to a better performance and increase the efficiency. This paper applies the consensus protocol for Multi-Agent Systems (MAS) to control the speed of multiple induction motors. In this paper, the behaviour of the system under different disturbances and scenarios has been simulated, thus, confirming the suitability and simplicity of this method for coordinating the control actions., QC 20151020