Power quality in LV distribution networks is already 1 a concern in many European countries especially where there 2 is a strong presence of renewable energy generation. Therefore 3 there is a growing interest in new solutions able to improve the 4 power quality level of such a system. Among them, an interesting 5 solution is represented by the open unified power quality con-6 ditioner (Open UPQC) proposed within the present work. The 7 system consists of a single or three-phase ac/dc power converter 8 installed at customer's premises and a main single or three-phase 9 ac/dc power converter in the MV/LV substation. The paper dis-10 cusses the design, simulation and implementation phases related 11 to an Open UPQC installed in a real LV distribution grid in 12 the city of Brescia (Italy) within the smart domo grid project, 13 co-funded by the Italian Ministry of Economic Development. 14 Results from the field installation show the effectiveness of the 15 proposed solution to face power quality issues in distribution 16 networks.

An automatic feedback control system (FCS) is presently being developed for the tokamak ASDEX Upgrade. The FCS will be used to control and/or suppress magneto-hydrodynamic instabilities, in particular neoclassical tearing modes and sawteeth, using its new, multi-frequency, electron cyclotron heating system, which allows the on-line fast steering of the poloidal injection angle. The FCS is conceived to couple with different time scales. The general features, strategy and first tests for a reliable controller are presented.

An important focus of the present research on thermonuclear fusion based on magnetic confinement is the control of rotating magnetic islands of low helical mode numbers m, n that are the nonlinear stage of resistive instabilities developing at magnetic surfaces where q = m/n. These perturbations are often driven by external resonant ‘error fields’ or mode coupling effects and maintained by local distortions of the current profile. The islands can be reduced in width or completely suppressed by a current driven by electron cyclotron waves accurately located within the island. A requisite for an effective control action is the ability to identify the relevant state variables (radial location, island amplitude, frequency and phase) in ‘real time’ and vary accordingly the control variables (wave beam power modulation and direction). Traditionally magnetohydrodynamic instabilities are monitored by external magnetic signals that however give no information about the radial location of the perturbation within the plasma. Here we describe the design of a real-time diagnostics/control device using an original algorithm for processing electron cyclotron emission signals to monitor temperature fluctuations and EC wave power deposition.

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