Study On The Insulation Coordination Of The AC Filters In Converter Station

Converter station AC filter banks are not only undertakes the system filtering work, alsofor the system to provide a reactive power capacity. The filter switching operation and fault,will produce a transient stress, if more than a component design transient rating, possiblydamaged elements. Therefore, the filter design, considering the actual running status under themost severe conditions, reasonable calculation of filter element transient rating, is to ensurethe safe operation of the filter. While limiting filter transient stress mainly through the metaloxide arrester (MOA), select the appropriate parameters of surge arrester, can reduce the filterelement subjected to transient stress, meet the security and economic requirements. Filtertransient value and insulation coordination of reducing filter failure rate in use, to ensure thestable operation of HVDC and the occurrence of transient fault after rapid recovery hasimportant significance.In the filter arrester configuration points selected, need to be calculated protectionelement MCOV, thereby the selected reference voltage of arrester. In the past engineeringdesign, is mainly based on traditional calculation formula, but may occur as a result of thecalculated MCOV too high leading to the surge arrester voltage reference to select case. Onthe basis of relevant regulations on the basis of the introduction of the two type, and thecalculation results were compared and analyzed, so as to choose the reference voltage ofarrester.In the filter for transient calculation in engineering, before considering only the operationshock and bus grounding fault in two different conditions. Considering the actual operation offilter according to the converter, voltage and reactive power exchange range of optimal filterperformance requirements of frequent switching, based on the study of the above twoconditions at the same time, increase the filter in the system of maximum and minimumshort-circuit capacity under the closed condition analysis.According to theoretical analysis, when the converter AC bus fault and continued forsome time after the resection of the fault line and DC blocking all extremely when, in the ACbus generated considerable excess voltage, called the load rejection over voltage. Thiscondition is often used to check the bus A type lightning arrester of the maximum energy, but from another point of view, this condition can also be applied to determine the AC filterelement maximum transient stress as well as the check of the energy filter. The thesis launchesthe research, using modeling and simulation results analysis for load rejection transient faultrecovery condition of AC filter setting effect.