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7 achievement(s) found As part of a gas compression plant installation project, the customer needed to validate and justify the sizing of the earth network in a way that complied with the standard in force for the step and touch voltages. [...]As part of a new town pilot study (eco-city concept), it was necessary to carry out a basic pilot project for the electricity distribution grid. [...]ITER is a very large-scale international scientific experiment for demonstrating the scientific and technological feasibility of electricity production using energy from nuclear fusion and leading to its industrial and commercial production.
CAPSIM is undertaking a project to assist its customer, ITER ORGANIZATION, in the selection of architecture and in sizing the HVA and HVB electrical power grids.
The study includes performing the initial sizing of electrical equipment that will in future be used for the grid to auxiliary systems of the ITER facility.
This grid, known as the Steady State Electrical Power Network (SSEPN), is connected to a double circuit 400 kV line. It is able to supply the ITER auxiliary systems, i.e. cooling, cryogenics and pumping systems, etc.
The total power of the installed loads is 160 MW and 80% have medium voltage induction motors.
The network contains high/medium voltage transformers supplying the principal busbars. At each start up, the required electrical power is distributed to the various production and generation sectors via the circuit breakers, cables and step-down transformers. [...]This study involved sizing 156 current transformers (CT) which will be installed on the HVA grid of an industrial site in the Middle East.
Sizing the current transformers is a critical step in the correct operation of the protection plan for an industrial grid. An unsuitable current transform may result in a protection device malfunctioning.
The project also involved sizing the single-pole tori used for protection at maximum earth current. [...]The Transient Recovery Voltage (TRV) is the voltage which appears across electrical equipment shortly after a current interruption. The waveform of the recovery voltage actually depends on the circuit configuration (inductive or capacitive nature). For example, a circuit breaker should be able to interrupt a given current for any recovery voltage provided that this value does not exceed its assigned TRV value (this TRV value is specified in the 61071 IEC standards).
The replacement of a HV circuit breaker, particularly in the case of replacement of SF6 circuit breakers by vacuum ones, requires the TRV calculations to be rechecked.
It is necessary to check that the generated overvoltages respect both the insulation levels of the present network equipment and the IEC assigned values of the breaking device. If the overvoltage levels are too high, then the installation overvoltage protection equipment should be considered (for example capacitors which reduce the rising edge steepness of overvoltages, RC circuits, surge arresters...). [...]The customer wished to be able to create and exploit an ETAP model of his LV (28V) DC network so as to study the electrical behavior in steady network conditions as well as during short-circuits.
CAPSIM was therefore requested for this mission for its expertise and knowledge of networks under strong technical and regulatory constraints (civilian and military nuclear, offshore rigs, complex scientific equipment, etc...) and its knowledge regarding electrical calculation tools. [...]For the extension of the EDF Saint Raphael source substation, EDF wished to validate the sizing of the earthing system of the substation. [...] | 
